Switch to keybase go-crypto (for some elliptic curve key) + test (#1925)

* Switch to keybase go-crypto (for some elliptic curve key) + test

* Use assert.NoError 

and add a little more context to failing test description

* Use assert.(No)Error everywhere 🌈

and assert.Error in place of .Nil/.NotNil

models/gpg_key.go

@@ -19,9 +19,9 @@ import (
 	"code.gitea.io/gitea/modules/log"
 
 	"github.com/go-xorm/xorm"
-	"golang.org/x/crypto/openpgp"
-	"golang.org/x/crypto/openpgp/armor"
-	"golang.org/x/crypto/openpgp/packet"
+	"github.com/keybase/go-crypto/openpgp"
+	"github.com/keybase/go-crypto/openpgp/armor"
+	"github.com/keybase/go-crypto/openpgp/packet"
 )
 
 // GPGKey represents a GPG key.

models/gpg_key_test.go

@@ -43,7 +43,28 @@ MkM/fdpyc2hY7Dl/+qFmN5MG5yGmMpQcX+RNNR222ibNC1D3wg==
 -----END PGP PUBLIC KEY BLOCK-----`
 
 	key, err := checkArmoredGPGKeyString(testGPGArmor)
-	assert.Nil(t, err, "Could not parse a valid GPG armored key", key)
+	assert.NoError(t, err, "Could not parse a valid GPG public armored rsa key", key)
+	//TODO verify value of key
+}
+
+func TestCheckArmoredbrainpoolP256r1GPGKeyString(t *testing.T) {
+	testGPGArmor := `-----BEGIN PGP PUBLIC KEY BLOCK-----
+Version: GnuPG v2
+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ZiSe
+-----END PGP PUBLIC KEY BLOCK-----`
+
+	key, err := checkArmoredGPGKeyString(testGPGArmor)
+	assert.NoError(t, err, "Could not parse a valid GPG public armored brainpoolP256r1 key", key)
 	//TODO verify value of key
 }
 
@@ -79,11 +100,11 @@ MkM/fdpyc2hY7Dl/+qFmN5MG5yGmMpQcX+RNNR222ibNC1D3wg==
 =i9b7
 -----END PGP PUBLIC KEY BLOCK-----`
 	ekey, err := checkArmoredGPGKeyString(testGPGArmor)
-	assert.Nil(t, err, "Could not parse a valid GPG armored key", ekey)
+	assert.NoError(t, err, "Could not parse a valid GPG armored key", ekey)
 
 	pubkey := ekey.PrimaryKey
 	content, err := base64EncPubKey(pubkey)
-	assert.Nil(t, err, "Could not base64 encode a valid PublicKey content", ekey)
+	assert.NoError(t, err, "Could not base64 encode a valid PublicKey content", ekey)
 
 	key := &GPGKey{
 		KeyID:             pubkey.KeyIdString(),
@@ -144,21 +165,21 @@ Unknown GPG key with good email
 `
 	//Reading Sign
 	goodSig, err := extractSignature(testGoodSigArmor)
-	assert.Nil(t, err, "Could not parse a valid GPG armored signature", testGoodSigArmor)
+	assert.NoError(t, err, "Could not parse a valid GPG armored signature", testGoodSigArmor)
 	badSig, err := extractSignature(testBadSigArmor)
-	assert.Nil(t, err, "Could not parse a valid GPG armored signature", testBadSigArmor)
+	assert.NoError(t, err, "Could not parse a valid GPG armored signature", testBadSigArmor)
 
 	//Generating hash of commit
 	goodHash, err := populateHash(goodSig.Hash, []byte(testGoodPayload))
-	assert.Nil(t, err, "Could not generate a valid hash of payload", testGoodPayload)
+	assert.NoError(t, err, "Could not generate a valid hash of payload", testGoodPayload)
 	badHash, err := populateHash(badSig.Hash, []byte(testBadPayload))
-	assert.Nil(t, err, "Could not generate a valid hash of payload", testBadPayload)
+	assert.NoError(t, err, "Could not generate a valid hash of payload", testBadPayload)
 
 	//Verify
 	err = verifySign(goodSig, goodHash, key)
-	assert.Nil(t, err, "Could not validate a good signature")
+	assert.NoError(t, err, "Could not validate a good signature")
 	err = verifySign(badSig, badHash, key)
-	assert.NotNil(t, err, "Validate a bad signature")
+	assert.Error(t, err, "Validate a bad signature")
 	err = verifySign(goodSig, goodHash, cannotsignkey)
-	assert.NotNil(t, err, "Validate a bad signature with a kay that can not sign")
+	assert.Error(t, err, "Validate a bad signature with a kay that can not sign")
 }

vendor/github.com/keybase/go-crypto/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/keybase/go-crypto/PATENTS

@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go.  This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation.  If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.

vendor/github.com/keybase/go-crypto/brainpool/brainpool.go

@@ -0,0 +1,134 @@
+// Package brainpool implements Brainpool elliptic curves.
+// Implementation of rcurves is from github.com/ebfe/brainpool
+// Note that these curves are implemented with naive, non-constant time operations
+// and are likely not suitable for enviroments where timing attacks are a concern.
+package brainpool
+
+import (
+	"crypto/elliptic"
+	"math/big"
+	"sync"
+)
+
+var (
+	once                   sync.Once
+	p256t1, p384t1, p512t1 *elliptic.CurveParams
+	p256r1, p384r1, p512r1 *rcurve
+)
+
+func initAll() {
+	initP256t1()
+	initP384t1()
+	initP512t1()
+	initP256r1()
+	initP384r1()
+	initP512r1()
+}
+
+func initP256t1() {
+	p256t1 = &elliptic.CurveParams{Name: "brainpoolP256t1"}
+	p256t1.P, _ = new(big.Int).SetString("A9FB57DBA1EEA9BC3E660A909D838D726E3BF623D52620282013481D1F6E5377", 16)
+	p256t1.N, _ = new(big.Int).SetString("A9FB57DBA1EEA9BC3E660A909D838D718C397AA3B561A6F7901E0E82974856A7", 16)
+	p256t1.B, _ = new(big.Int).SetString("662C61C430D84EA4FE66A7733D0B76B7BF93EBC4AF2F49256AE58101FEE92B04", 16)
+	p256t1.Gx, _ = new(big.Int).SetString("A3E8EB3CC1CFE7B7732213B23A656149AFA142C47AAFBC2B79A191562E1305F4", 16)
+	p256t1.Gy, _ = new(big.Int).SetString("2D996C823439C56D7F7B22E14644417E69BCB6DE39D027001DABE8F35B25C9BE", 16)
+	p256t1.BitSize = 256
+}
+
+func initP256r1() {
+	twisted := p256t1
+	params := &elliptic.CurveParams{
+		Name:    "brainpoolP256r1",
+		P:       twisted.P,
+		N:       twisted.N,
+		BitSize: twisted.BitSize,
+	}
+	params.Gx, _ = new(big.Int).SetString("8BD2AEB9CB7E57CB2C4B482FFC81B7AFB9DE27E1E3BD23C23A4453BD9ACE3262", 16)
+	params.Gy, _ = new(big.Int).SetString("547EF835C3DAC4FD97F8461A14611DC9C27745132DED8E545C1D54C72F046997", 16)
+	z, _ := new(big.Int).SetString("3E2D4BD9597B58639AE7AA669CAB9837CF5CF20A2C852D10F655668DFC150EF0", 16)
+	p256r1 = newrcurve(twisted, params, z)
+}
+
+func initP384t1() {
+	p384t1 = &elliptic.CurveParams{Name: "brainpoolP384t1"}
+	p384t1.P, _ = new(big.Int).SetString("8CB91E82A3386D280F5D6F7E50E641DF152F7109ED5456B412B1DA197FB71123ACD3A729901D1A71874700133107EC53", 16)
+	p384t1.N, _ = new(big.Int).SetString("8CB91E82A3386D280F5D6F7E50E641DF152F7109ED5456B31F166E6CAC0425A7CF3AB6AF6B7FC3103B883202E9046565", 16)
+	p384t1.B, _ = new(big.Int).SetString("7F519EADA7BDA81BD826DBA647910F8C4B9346ED8CCDC64E4B1ABD11756DCE1D2074AA263B88805CED70355A33B471EE", 16)
+	p384t1.Gx, _ = new(big.Int).SetString("18DE98B02DB9A306F2AFCD7235F72A819B80AB12EBD653172476FECD462AABFFC4FF191B946A5F54D8D0AA2F418808CC", 16)
+	p384t1.Gy, _ = new(big.Int).SetString("25AB056962D30651A114AFD2755AD336747F93475B7A1FCA3B88F2B6A208CCFE469408584DC2B2912675BF5B9E582928", 16)
+	p384t1.BitSize = 384
+}
+
+func initP384r1() {
+	twisted := p384t1
+	params := &elliptic.CurveParams{
+		Name:    "brainpoolP384r1",
+		P:       twisted.P,
+		N:       twisted.N,
+		BitSize: twisted.BitSize,
+	}
+	params.Gx, _ = new(big.Int).SetString("1D1C64F068CF45FFA2A63A81B7C13F6B8847A3E77EF14FE3DB7FCAFE0CBD10E8E826E03436D646AAEF87B2E247D4AF1E", 16)
+	params.Gy, _ = new(big.Int).SetString("8ABE1D7520F9C2A45CB1EB8E95CFD55262B70B29FEEC5864E19C054FF99129280E4646217791811142820341263C5315", 16)
+	z, _ := new(big.Int).SetString("41DFE8DD399331F7166A66076734A89CD0D2BCDB7D068E44E1F378F41ECBAE97D2D63DBC87BCCDDCCC5DA39E8589291C", 16)
+	p384r1 = newrcurve(twisted, params, z)
+}
+
+func initP512t1() {
+	p512t1 = &elliptic.CurveParams{Name: "brainpoolP512t1"}
+	p512t1.P, _ = new(big.Int).SetString("AADD9DB8DBE9C48B3FD4E6AE33C9FC07CB308DB3B3C9D20ED6639CCA703308717D4D9B009BC66842AECDA12AE6A380E62881FF2F2D82C68528AA6056583A48F3", 16)
+	p512t1.N, _ = new(big.Int).SetString("AADD9DB8DBE9C48B3FD4E6AE33C9FC07CB308DB3B3C9D20ED6639CCA70330870553E5C414CA92619418661197FAC10471DB1D381085DDADDB58796829CA90069", 16)
+	p512t1.B, _ = new(big.Int).SetString("7CBBBCF9441CFAB76E1890E46884EAE321F70C0BCB4981527897504BEC3E36A62BCDFA2304976540F6450085F2DAE145C22553B465763689180EA2571867423E", 16)
+	p512t1.Gx, _ = new(big.Int).SetString("640ECE5C12788717B9C1BA06CBC2A6FEBA85842458C56DDE9DB1758D39C0313D82BA51735CDB3EA499AA77A7D6943A64F7A3F25FE26F06B51BAA2696FA9035DA", 16)
+	p512t1.Gy, _ = new(big.Int).SetString("5B534BD595F5AF0FA2C892376C84ACE1BB4E3019B71634C01131159CAE03CEE9D9932184BEEF216BD71DF2DADF86A627306ECFF96DBB8BACE198B61E00F8B332", 16)
+	p512t1.BitSize = 512
+}
+
+func initP512r1() {
+	twisted := p512t1
+	params := &elliptic.CurveParams{
+		Name:    "brainpoolP512r1",
+		P:       twisted.P,
+		N:       twisted.N,
+		BitSize: twisted.BitSize,
+	}
+	params.Gx, _ = new(big.Int).SetString("81AEE4BDD82ED9645A21322E9C4C6A9385ED9F70B5D916C1B43B62EEF4D0098EFF3B1F78E2D0D48D50D1687B93B97D5F7C6D5047406A5E688B352209BCB9F822", 16)
+	params.Gy, _ = new(big.Int).SetString("7DDE385D566332ECC0EABFA9CF7822FDF209F70024A57B1AA000C55B881F8111B2DCDE494A5F485E5BCA4BD88A2763AED1CA2B2FA8F0540678CD1E0F3AD80892", 16)
+	z, _ := new(big.Int).SetString("12EE58E6764838B69782136F0F2D3BA06E27695716054092E60A80BEDB212B64E585D90BCE13761F85C3F1D2A64E3BE8FEA2220F01EBA5EEB0F35DBD29D922AB", 16)
+	p512r1 = newrcurve(twisted, params, z)
+}
+
+// P256t1 returns a Curve which implements Brainpool P256t1 (see RFC 5639, section 3.4)
+func P256t1() elliptic.Curve {
+	once.Do(initAll)
+	return p256t1
+}
+
+// P256r1 returns a Curve which implements Brainpool P256r1 (see RFC 5639, section 3.4)
+func P256r1() elliptic.Curve {
+	once.Do(initAll)
+	return p256r1
+}
+
+// P384t1 returns a Curve which implements Brainpool P384t1 (see RFC 5639, section 3.6)
+func P384t1() elliptic.Curve {
+	once.Do(initAll)
+	return p384t1
+}
+
+// P384r1 returns a Curve which implements Brainpool P384r1 (see RFC 5639, section 3.6)
+func P384r1() elliptic.Curve {
+	once.Do(initAll)
+	return p384r1
+}
+
+// P512t1 returns a Curve which implements Brainpool P512t1 (see RFC 5639, section 3.7)
+func P512t1() elliptic.Curve {
+	once.Do(initAll)
+	return p512t1
+}
+
+// P512r1 returns a Curve which implements Brainpool P512r1 (see RFC 5639, section 3.7)
+func P512r1() elliptic.Curve {
+	once.Do(initAll)
+	return p512r1
+}

vendor/github.com/keybase/go-crypto/brainpool/rcurve.go

@@ -0,0 +1,83 @@
+package brainpool
+
+import (
+	"crypto/elliptic"
+	"math/big"
+)
+
+var _ elliptic.Curve = (*rcurve)(nil)
+
+type rcurve struct {
+	twisted elliptic.Curve
+	params  *elliptic.CurveParams
+	z       *big.Int
+	zinv    *big.Int
+	z2      *big.Int
+	z3      *big.Int
+	zinv2   *big.Int
+	zinv3   *big.Int
+}
+
+var (
+	two   = big.NewInt(2)
+	three = big.NewInt(3)
+)
+
+func newrcurve(twisted elliptic.Curve, params *elliptic.CurveParams, z *big.Int) *rcurve {
+	zinv := new(big.Int).ModInverse(z, params.P)
+	return &rcurve{
+		twisted: twisted,
+		params:  params,
+		z:       z,
+		zinv:    zinv,
+		z2:      new(big.Int).Exp(z, two, params.P),
+		z3:      new(big.Int).Exp(z, three, params.P),
+		zinv2:   new(big.Int).Exp(zinv, two, params.P),
+		zinv3:   new(big.Int).Exp(zinv, three, params.P),
+	}
+}
+
+func (curve *rcurve) toTwisted(x, y *big.Int) (*big.Int, *big.Int) {
+	var tx, ty big.Int
+	tx.Mul(x, curve.z2)
+	tx.Mod(&tx, curve.params.P)
+	ty.Mul(y, curve.z3)
+	ty.Mod(&ty, curve.params.P)
+	return &tx, &ty
+}
+
+func (curve *rcurve) fromTwisted(tx, ty *big.Int) (*big.Int, *big.Int) {
+	var x, y big.Int
+	x.Mul(tx, curve.zinv2)
+	x.Mod(&x, curve.params.P)
+	y.Mul(ty, curve.zinv3)
+	y.Mod(&y, curve.params.P)
+	return &x, &y
+}
+
+func (curve *rcurve) Params() *elliptic.CurveParams {
+	return curve.params
+}
+
+func (curve *rcurve) IsOnCurve(x, y *big.Int) bool {
+	return curve.twisted.IsOnCurve(curve.toTwisted(x, y))
+}
+
+func (curve *rcurve) Add(x1, y1, x2, y2 *big.Int) (x, y *big.Int) {
+	tx1, ty1 := curve.toTwisted(x1, y1)
+	tx2, ty2 := curve.toTwisted(x2, y2)
+	return curve.fromTwisted(curve.twisted.Add(tx1, ty1, tx2, ty2))
+}
+
+func (curve *rcurve) Double(x1, y1 *big.Int) (x, y *big.Int) {
+	return curve.fromTwisted(curve.twisted.Double(curve.toTwisted(x1, y1)))
+}
+
+func (curve *rcurve) ScalarMult(x1, y1 *big.Int, scalar []byte) (x, y *big.Int) {
+	tx1, ty1 := curve.toTwisted(x1, y1)
+	return curve.fromTwisted(curve.twisted.ScalarMult(tx1, ty1, scalar))
+}
+
+func (curve *rcurve) ScalarBaseMult(scalar []byte) (x, y *big.Int) {
+	return curve.fromTwisted(curve.twisted.ScalarBaseMult(scalar))
+}

vendor/github.com/keybase/go-crypto/cast5/cast5.go

@@ -4,7 +4,7 @@
 
 // Package cast5 implements CAST5, as defined in RFC 2144. CAST5 is a common
 // OpenPGP cipher.
-package cast5 // import "golang.org/x/crypto/cast5"
+package cast5
 
 import "errors"
 

vendor/github.com/keybase/go-crypto/curve25519/const_amd64.s

@@ -0,0 +1,20 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This code was translated into a form compatible with 6a from the public
+// domain sources in SUPERCOP: http://bench.cr.yp.to/supercop.html
+
+// +build amd64,!gccgo,!appengine
+
+DATA ·REDMASK51(SB)/8, $0x0007FFFFFFFFFFFF
+GLOBL ·REDMASK51(SB), 8, $8
+
+DATA ·_121666_213(SB)/8, $996687872
+GLOBL ·_121666_213(SB), 8, $8
+
+DATA ·_2P0(SB)/8, $0xFFFFFFFFFFFDA
+GLOBL ·_2P0(SB), 8, $8
+
+DATA ·_2P1234(SB)/8, $0xFFFFFFFFFFFFE
+GLOBL ·_2P1234(SB), 8, $8

vendor/github.com/keybase/go-crypto/curve25519/cswap_amd64.s

@@ -0,0 +1,88 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This code was translated into a form compatible with 6a from the public
+// domain sources in SUPERCOP: http://bench.cr.yp.to/supercop.html
+
+// +build amd64,!gccgo,!appengine
+
+// func cswap(inout *[5]uint64, v uint64)
+TEXT ·cswap(SB),7,$0
+	MOVQ inout+0(FP),DI
+	MOVQ v+8(FP),SI
+
+	CMPQ SI,$1
+	MOVQ 0(DI),SI
+	MOVQ 80(DI),DX
+	MOVQ 8(DI),CX
+	MOVQ 88(DI),R8
+	MOVQ SI,R9
+	CMOVQEQ DX,SI
+	CMOVQEQ R9,DX
+	MOVQ CX,R9
+	CMOVQEQ R8,CX
+	CMOVQEQ R9,R8
+	MOVQ SI,0(DI)
+	MOVQ DX,80(DI)
+	MOVQ CX,8(DI)
+	MOVQ R8,88(DI)
+	MOVQ 16(DI),SI
+	MOVQ 96(DI),DX
+	MOVQ 24(DI),CX
+	MOVQ 104(DI),R8
+	MOVQ SI,R9
+	CMOVQEQ DX,SI
+	CMOVQEQ R9,DX
+	MOVQ CX,R9
+	CMOVQEQ R8,CX
+	CMOVQEQ R9,R8
+	MOVQ SI,16(DI)
+	MOVQ DX,96(DI)
+	MOVQ CX,24(DI)
+	MOVQ R8,104(DI)
+	MOVQ 32(DI),SI
+	MOVQ 112(DI),DX
+	MOVQ 40(DI),CX
+	MOVQ 120(DI),R8
+	MOVQ SI,R9
+	CMOVQEQ DX,SI
+	CMOVQEQ R9,DX
+	MOVQ CX,R9
+	CMOVQEQ R8,CX
+	CMOVQEQ R9,R8
+	MOVQ SI,32(DI)
+	MOVQ DX,112(DI)
+	MOVQ CX,40(DI)
+	MOVQ R8,120(DI)
+	MOVQ 48(DI),SI
+	MOVQ 128(DI),DX
+	MOVQ 56(DI),CX
+	MOVQ 136(DI),R8
+	MOVQ SI,R9
+	CMOVQEQ DX,SI
+	CMOVQEQ R9,DX
+	MOVQ CX,R9
+	CMOVQEQ R8,CX
+	CMOVQEQ R9,R8
+	MOVQ SI,48(DI)
+	MOVQ DX,128(DI)
+	MOVQ CX,56(DI)
+	MOVQ R8,136(DI)
+	MOVQ 64(DI),SI
+	MOVQ 144(DI),DX
+	MOVQ 72(DI),CX
+	MOVQ 152(DI),R8
+	MOVQ SI,R9
+	CMOVQEQ DX,SI
+	CMOVQEQ R9,DX
+	MOVQ CX,R9
+	CMOVQEQ R8,CX
+	CMOVQEQ R9,R8
+	MOVQ SI,64(DI)
+	MOVQ DX,144(DI)
+	MOVQ CX,72(DI)
+	MOVQ R8,152(DI)
+	MOVQ DI,AX
+	MOVQ SI,DX
+	RET

vendor/github.com/keybase/go-crypto/curve25519/curve25519.go

@@ -0,0 +1,841 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// We have a implementation in amd64 assembly so this code is only run on
+// non-amd64 platforms. The amd64 assembly does not support gccgo.
+// +build !amd64 gccgo appengine
+
+package curve25519
+
+// This code is a port of the public domain, "ref10" implementation of
+// curve25519 from SUPERCOP 20130419 by D. J. Bernstein.
+
+// fieldElement represents an element of the field GF(2^255 - 19). An element
+// t, entries t[0]...t[9], represents the integer t[0]+2^26 t[1]+2^51 t[2]+2^77
+// t[3]+2^102 t[4]+...+2^230 t[9]. Bounds on each t[i] vary depending on
+// context.
+type fieldElement [10]int32
+
+func feZero(fe *fieldElement) {
+	for i := range fe {
+		fe[i] = 0
+	}
+}
+
+func feOne(fe *fieldElement) {
+	feZero(fe)
+	fe[0] = 1
+}
+
+func feAdd(dst, a, b *fieldElement) {
+	for i := range dst {
+		dst[i] = a[i] + b[i]
+	}
+}
+
+func feSub(dst, a, b *fieldElement) {
+	for i := range dst {
+		dst[i] = a[i] - b[i]
+	}
+}
+
+func feCopy(dst, src *fieldElement) {
+	for i := range dst {
+		dst[i] = src[i]
+	}
+}
+
+// feCSwap replaces (f,g) with (g,f) if b == 1; replaces (f,g) with (f,g) if b == 0.
+//
+// Preconditions: b in {0,1}.
+func feCSwap(f, g *fieldElement, b int32) {
+	var x fieldElement
+	b = -b
+	for i := range x {
+		x[i] = b & (f[i] ^ g[i])
+	}
+
+	for i := range f {
+		f[i] ^= x[i]
+	}
+	for i := range g {
+		g[i] ^= x[i]
+	}
+}
+
+// load3 reads a 24-bit, little-endian value from in.
+func load3(in []byte) int64 {
+	var r int64
+	r = int64(in[0])
+	r |= int64(in[1]) << 8
+	r |= int64(in[2]) << 16
+	return r
+}
+
+// load4 reads a 32-bit, little-endian value from in.
+func load4(in []byte) int64 {
+	var r int64
+	r = int64(in[0])
+	r |= int64(in[1]) << 8
+	r |= int64(in[2]) << 16
+	r |= int64(in[3]) << 24
+	return r
+}
+
+func feFromBytes(dst *fieldElement, src *[32]byte) {
+	h0 := load4(src[:])
+	h1 := load3(src[4:]) << 6
+	h2 := load3(src[7:]) << 5
+	h3 := load3(src[10:]) << 3
+	h4 := load3(src[13:]) << 2
+	h5 := load4(src[16:])
+	h6 := load3(src[20:]) << 7
+	h7 := load3(src[23:]) << 5
+	h8 := load3(src[26:]) << 4
+	h9 := load3(src[29:]) << 2
+
+	var carry [10]int64
+	carry[9] = (h9 + 1<<24) >> 25
+	h0 += carry[9] * 19
+	h9 -= carry[9] << 25
+	carry[1] = (h1 + 1<<24) >> 25
+	h2 += carry[1]
+	h1 -= carry[1] << 25
+	carry[3] = (h3 + 1<<24) >> 25
+	h4 += carry[3]
+	h3 -= carry[3] << 25
+	carry[5] = (h5 + 1<<24) >> 25
+	h6 += carry[5]
+	h5 -= carry[5] << 25
+	carry[7] = (h7 + 1<<24) >> 25
+	h8 += carry[7]
+	h7 -= carry[7] << 25
+
+	carry[0] = (h0 + 1<<25) >> 26
+	h1 += carry[0]
+	h0 -= carry[0] << 26
+	carry[2] = (h2 + 1<<25) >> 26
+	h3 += carry[2]
+	h2 -= carry[2] << 26
+	carry[4] = (h4 + 1<<25) >> 26
+	h5 += carry[4]
+	h4 -= carry[4] << 26
+	carry[6] = (h6 + 1<<25) >> 26
+	h7 += carry[6]
+	h6 -= carry[6] << 26
+	carry[8] = (h8 + 1<<25) >> 26
+	h9 += carry[8]
+	h8 -= carry[8] << 26
+
+	dst[0] = int32(h0)
+	dst[1] = int32(h1)
+	dst[2] = int32(h2)
+	dst[3] = int32(h3)
+	dst[4] = int32(h4)
+	dst[5] = int32(h5)
+	dst[6] = int32(h6)
+	dst[7] = int32(h7)
+	dst[8] = int32(h8)
+	dst[9] = int32(h9)
+}
+
+// feToBytes marshals h to s.
+// Preconditions:
+//   |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
+//
+// Write p=2^255-19; q=floor(h/p).
+// Basic claim: q = floor(2^(-255)(h + 19 2^(-25)h9 + 2^(-1))).
+//
+// Proof:
+//   Have |h|<=p so |q|<=1 so |19^2 2^(-255) q|<1/4.
+//   Also have |h-2^230 h9|<2^230 so |19 2^(-255)(h-2^230 h9)|<1/4.
+//
+//   Write y=2^(-1)-19^2 2^(-255)q-19 2^(-255)(h-2^230 h9).
+//   Then 0<y<1.
+//
+//   Write r=h-pq.
+//   Have 0<=r<=p-1=2^255-20.
+//   Thus 0<=r+19(2^-255)r<r+19(2^-255)2^255<=2^255-1.
+//
+//   Write x=r+19(2^-255)r+y.
+//   Then 0<x<2^255 so floor(2^(-255)x) = 0 so floor(q+2^(-255)x) = q.
+//
+//   Have q+2^(-255)x = 2^(-255)(h + 19 2^(-25) h9 + 2^(-1))
+//   so floor(2^(-255)(h + 19 2^(-25) h9 + 2^(-1))) = q.
+func feToBytes(s *[32]byte, h *fieldElement) {
+	var carry [10]int32
+
+	q := (19*h[9] + (1 << 24)) >> 25
+	q = (h[0] + q) >> 26
+	q = (h[1] + q) >> 25
+	q = (h[2] + q) >> 26
+	q = (h[3] + q) >> 25
+	q = (h[4] + q) >> 26
+	q = (h[5] + q) >> 25
+	q = (h[6] + q) >> 26
+	q = (h[7] + q) >> 25
+	q = (h[8] + q) >> 26
+	q = (h[9] + q) >> 25
+
+	// Goal: Output h-(2^255-19)q, which is between 0 and 2^255-20.
+	h[0] += 19 * q
+	// Goal: Output h-2^255 q, which is between 0 and 2^255-20.
+
+	carry[0] = h[0] >> 26
+	h[1] += carry[0]
+	h[0] -= carry[0] << 26
+	carry[1] = h[1] >> 25
+	h[2] += carry[1]
+	h[1] -= carry[1] << 25
+	carry[2] = h[2] >> 26
+	h[3] += carry[2]
+	h[2] -= carry[2] << 26
+	carry[3] = h[3] >> 25
+	h[4] += carry[3]
+	h[3] -= carry[3] << 25
+	carry[4] = h[4] >> 26
+	h[5] += carry[4]
+	h[4] -= carry[4] << 26
+	carry[5] = h[5] >> 25
+	h[6] += carry[5]
+	h[5] -= carry[5] << 25
+	carry[6] = h[6] >> 26
+	h[7] += carry[6]
+	h[6] -= carry[6] << 26
+	carry[7] = h[7] >> 25
+	h[8] += carry[7]
+	h[7] -= carry[7] << 25
+	carry[8] = h[8] >> 26
+	h[9] += carry[8]
+	h[8] -= carry[8] << 26
+	carry[9] = h[9] >> 25
+	h[9] -= carry[9] << 25
+	// h10 = carry9
+
+	// Goal: Output h[0]+...+2^255 h10-2^255 q, which is between 0 and 2^255-20.
+	// Have h[0]+...+2^230 h[9] between 0 and 2^255-1;
+	// evidently 2^255 h10-2^255 q = 0.
+	// Goal: Output h[0]+...+2^230 h[9].
+
+	s[0] = byte(h[0] >> 0)
+	s[1] = byte(h[0] >> 8)
+	s[2] = byte(h[0] >> 16)
+	s[3] = byte((h[0] >> 24) | (h[1] << 2))
+	s[4] = byte(h[1] >> 6)
+	s[5] = byte(h[1] >> 14)
+	s[6] = byte((h[1] >> 22) | (h[2] << 3))
+	s[7] = byte(h[2] >> 5)
+	s[8] = byte(h[2] >> 13)
+	s[9] = byte((h[2] >> 21) | (h[3] << 5))
+	s[10] = byte(h[3] >> 3)
+	s[11] = byte(h[3] >> 11)
+	s[12] = byte((h[3] >> 19) | (h[4] << 6))
+	s[13] = byte(h[4] >> 2)
+	s[14] = byte(h[4] >> 10)
+	s[15] = byte(h[4] >> 18)
+	s[16] = byte(h[5] >> 0)
+	s[17] = byte(h[5] >> 8)
+	s[18] = byte(h[5] >> 16)
+	s[19] = byte((h[5] >> 24) | (h[6] << 1))
+	s[20] = byte(h[6] >> 7)
+	s[21] = byte(h[6] >> 15)
+	s[22] = byte((h[6] >> 23) | (h[7] << 3))
+	s[23] = byte(h[7] >> 5)
+	s[24] = byte(h[7] >> 13)
+	s[25] = byte((h[7] >> 21) | (h[8] << 4))
+	s[26] = byte(h[8] >> 4)
+	s[27] = byte(h[8] >> 12)
+	s[28] = byte((h[8] >> 20) | (h[9] << 6))
+	s[29] = byte(h[9] >> 2)
+	s[30] = byte(h[9] >> 10)
+	s[31] = byte(h[9] >> 18)
+}
+
+// feMul calculates h = f * g
+// Can overlap h with f or g.
+//
+// Preconditions:
+//    |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
+//    |g| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
+//
+// Postconditions:
+//    |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
+//
+// Notes on implementation strategy:
+//
+// Using schoolbook multiplication.
+// Karatsuba would save a little in some cost models.
+//
+// Most multiplications by 2 and 19 are 32-bit precomputations;
+// cheaper than 64-bit postcomputations.
+//
+// There is one remaining multiplication by 19 in the carry chain;
+// one *19 precomputation can be merged into this,
+// but the resulting data flow is considerably less clean.
+//
+// There are 12 carries below.
+// 10 of them are 2-way parallelizable and vectorizable.
+// Can get away with 11 carries, but then data flow is much deeper.
+//
+// With tighter constraints on inputs can squeeze carries into int32.
+func feMul(h, f, g *fieldElement) {
+	f0 := f[0]
+	f1 := f[1]
+	f2 := f[2]
+	f3 := f[3]
+	f4 := f[4]
+	f5 := f[5]
+	f6 := f[6]
+	f7 := f[7]
+	f8 := f[8]
+	f9 := f[9]
+	g0 := g[0]
+	g1 := g[1]
+	g2 := g[2]
+	g3 := g[3]
+	g4 := g[4]
+	g5 := g[5]
+	g6 := g[6]
+	g7 := g[7]
+	g8 := g[8]
+	g9 := g[9]
+	g1_19 := 19 * g1 // 1.4*2^29
+	g2_19 := 19 * g2 // 1.4*2^30; still ok
+	g3_19 := 19 * g3
+	g4_19 := 19 * g4
+	g5_19 := 19 * g5
+	g6_19 := 19 * g6
+	g7_19 := 19 * g7
+	g8_19 := 19 * g8
+	g9_19 := 19 * g9
+	f1_2 := 2 * f1
+	f3_2 := 2 * f3
+	f5_2 := 2 * f5
+	f7_2 := 2 * f7
+	f9_2 := 2 * f9
+	f0g0 := int64(f0) * int64(g0)
+	f0g1 := int64(f0) * int64(g1)
+	f0g2 := int64(f0) * int64(g2)
+	f0g3 := int64(f0) * int64(g3)
+	f0g4 := int64(f0) * int64(g4)
+	f0g5 := int64(f0) * int64(g5)
+	f0g6 := int64(f0) * int64(g6)
+	f0g7 := int64(f0) * int64(g7)
+	f0g8 := int64(f0) * int64(g8)
+	f0g9 := int64(f0) * int64(g9)
+	f1g0 := int64(f1) * int64(g0)
+	f1g1_2 := int64(f1_2) * int64(g1)
+	f1g2 := int64(f1) * int64(g2)
+	f1g3_2 := int64(f1_2) * int64(g3)
+	f1g4 := int64(f1) * int64(g4)
+	f1g5_2 := int64(f1_2) * int64(g5)
+	f1g6 := int64(f1) * int64(g6)
+	f1g7_2 := int64(f1_2) * int64(g7)
+	f1g8 := int64(f1) * int64(g8)
+	f1g9_38 := int64(f1_2) * int64(g9_19)
+	f2g0 := int64(f2) * int64(g0)
+	f2g1 := int64(f2) * int64(g1)
+	f2g2 := int64(f2) * int64(g2)
+	f2g3 := int64(f2) * int64(g3)
+	f2g4 := int64(f2) * int64(g4)
+	f2g5 := int64(f2) * int64(g5)
+	f2g6 := int64(f2) * int64(g6)
+	f2g7 := int64(f2) * int64(g7)
+	f2g8_19 := int64(f2) * int64(g8_19)
+	f2g9_19 := int64(f2) * int64(g9_19)
+	f3g0 := int64(f3) * int64(g0)
+	f3g1_2 := int64(f3_2) * int64(g1)
+	f3g2 := int64(f3) * int64(g2)
+	f3g3_2 := int64(f3_2) * int64(g3)
+	f3g4 := int64(f3) * int64(g4)
+	f3g5_2 := int64(f3_2) * int64(g5)
+	f3g6 := int64(f3) * int64(g6)
+	f3g7_38 := int64(f3_2) * int64(g7_19)
+	f3g8_19 := int64(f3) * int64(g8_19)
+	f3g9_38 := int64(f3_2) * int64(g9_19)
+	f4g0 := int64(f4) * int64(g0)
+	f4g1 := int64(f4) * int64(g1)
+	f4g2 := int64(f4) * int64(g2)
+	f4g3 := int64(f4) * int64(g3)
+	f4g4 := int64(f4) * int64(g4)
+	f4g5 := int64(f4) * int64(g5)
+	f4g6_19 := int64(f4) * int64(g6_19)
+	f4g7_19 := int64(f4) * int64(g7_19)
+	f4g8_19 := int64(f4) * int64(g8_19)
+	f4g9_19 := int64(f4) * int64(g9_19)
+	f5g0 := int64(f5) * int64(g0)
+	f5g1_2 := int64(f5_2) * int64(g1)
+	f5g2 := int64(f5) * int64(g2)
+	f5g3_2 := int64(f5_2) * int64(g3)
+	f5g4 := int64(f5) * int64(g4)
+	f5g5_38 := int64(f5_2) * int64(g5_19)
+	f5g6_19 := int64(f5) * int64(g6_19)
+	f5g7_38 := int64(f5_2) * int64(g7_19)
+	f5g8_19 := int64(f5) * int64(g8_19)
+	f5g9_38 := int64(f5_2) * int64(g9_19)
+	f6g0 := int64(f6) * int64(g0)
+	f6g1 := int64(f6) * int64(g1)
+	f6g2 := int64(f6) * int64(g2)
+	f6g3 := int64(f6) * int64(g3)
+	f6g4_19 := int64(f6) * int64(g4_19)
+	f6g5_19 := int64(f6) * int64(g5_19)
+	f6g6_19 := int64(f6) * int64(g6_19)
+	f6g7_19 := int64(f6) * int64(g7_19)
+	f6g8_19 := int64(f6) * int64(g8_19)
+	f6g9_19 := int64(f6) * int64(g9_19)
+	f7g0 := int64(f7) * int64(g0)
+	f7g1_2 := int64(f7_2) * int64(g1)
+	f7g2 := int64(f7) * int64(g2)
+	f7g3_38 := int64(f7_2) * int64(g3_19)
+	f7g4_19 := int64(f7) * int64(g4_19)
+	f7g5_38 := int64(f7_2) * int64(g5_19)
+	f7g6_19 := int64(f7) * int64(g6_19)
+	f7g7_38 := int64(f7_2) * int64(g7_19)
+	f7g8_19 := int64(f7) * int64(g8_19)
+	f7g9_38 := int64(f7_2) * int64(g9_19)
+	f8g0 := int64(f8) * int64(g0)
+	f8g1 := int64(f8) * int64(g1)
+	f8g2_19 := int64(f8) * int64(g2_19)
+	f8g3_19 := int64(f8) * int64(g3_19)
+	f8g4_19 := int64(f8) * int64(g4_19)
+	f8g5_19 := int64(f8) * int64(g5_19)
+	f8g6_19 := int64(f8) * int64(g6_19)
+	f8g7_19 := int64(f8) * int64(g7_19)
+	f8g8_19 := int64(f8) * int64(g8_19)
+	f8g9_19 := int64(f8) * int64(g9_19)
+	f9g0 := int64(f9) * int64(g0)
+	f9g1_38 := int64(f9_2) * int64(g1_19)
+	f9g2_19 := int64(f9) * int64(g2_19)
+	f9g3_38 := int64(f9_2) * int64(g3_19)
+	f9g4_19 := int64(f9) * int64(g4_19)
+	f9g5_38 := int64(f9_2) * int64(g5_19)
+	f9g6_19 := int64(f9) * int64(g6_19)
+	f9g7_38 := int64(f9_2) * int64(g7_19)
+	f9g8_19 := int64(f9) * int64(g8_19)
+	f9g9_38 := int64(f9_2) * int64(g9_19)
+	h0 := f0g0 + f1g9_38 + f2g8_19 + f3g7_38 + f4g6_19 + f5g5_38 + f6g4_19 + f7g3_38 + f8g2_19 + f9g1_38
+	h1 := f0g1 + f1g0 + f2g9_19 + f3g8_19 + f4g7_19 + f5g6_19 + f6g5_19 + f7g4_19 + f8g3_19 + f9g2_19
+	h2 := f0g2 + f1g1_2 + f2g0 + f3g9_38 + f4g8_19 + f5g7_38 + f6g6_19 + f7g5_38 + f8g4_19 + f9g3_38
+	h3 := f0g3 + f1g2 + f2g1 + f3g0 + f4g9_19 + f5g8_19 + f6g7_19 + f7g6_19 + f8g5_19 + f9g4_19
+	h4 := f0g4 + f1g3_2 + f2g2 + f3g1_2 + f4g0 + f5g9_38 + f6g8_19 + f7g7_38 + f8g6_19 + f9g5_38
+	h5 := f0g5 + f1g4 + f2g3 + f3g2 + f4g1 + f5g0 + f6g9_19 + f7g8_19 + f8g7_19 + f9g6_19
+	h6 := f0g6 + f1g5_2 + f2g4 + f3g3_2 + f4g2 + f5g1_2 + f6g0 + f7g9_38 + f8g8_19 + f9g7_38
+	h7 := f0g7 + f1g6 + f2g5 + f3g4 + f4g3 + f5g2 + f6g1 + f7g0 + f8g9_19 + f9g8_19
+	h8 := f0g8 + f1g7_2 + f2g6 + f3g5_2 + f4g4 + f5g3_2 + f6g2 + f7g1_2 + f8g0 + f9g9_38
+	h9 := f0g9 + f1g8 + f2g7 + f3g6 + f4g5 + f5g4 + f6g3 + f7g2 + f8g1 + f9g0
+	var carry [10]int64
+
+	// |h0| <= (1.1*1.1*2^52*(1+19+19+19+19)+1.1*1.1*2^50*(38+38+38+38+38))
+	//   i.e. |h0| <= 1.2*2^59; narrower ranges for h2, h4, h6, h8
+	// |h1| <= (1.1*1.1*2^51*(1+1+19+19+19+19+19+19+19+19))
+	//   i.e. |h1| <= 1.5*2^58; narrower ranges for h3, h5, h7, h9
+
+	carry[0] = (h0 + (1 << 25)) >> 26
+	h1 += carry[0]
+	h0 -= carry[0] << 26
+	carry[4] = (h4 + (1 << 25)) >> 26
+	h5 += carry[4]
+	h4 -= carry[4] << 26
+	// |h0| <= 2^25
+	// |h4| <= 2^25
+	// |h1| <= 1.51*2^58
+	// |h5| <= 1.51*2^58
+
+	carry[1] = (h1 + (1 << 24)) >> 25
+	h2 += carry[1]
+	h1 -= carry[1] << 25
+	carry[5] = (h5 + (1 << 24)) >> 25
+	h6 += carry[5]
+	h5 -= carry[5] << 25
+	// |h1| <= 2^24; from now on fits into int32
+	// |h5| <= 2^24; from now on fits into int32
+	// |h2| <= 1.21*2^59
+	// |h6| <= 1.21*2^59
+
+	carry[2] = (h2 + (1 << 25)) >> 26
+	h3 += carry[2]
+	h2 -= carry[2] << 26
+	carry[6] = (h6 + (1 << 25)) >> 26
+	h7 += carry[6]
+	h6 -= carry[6] << 26
+	// |h2| <= 2^25; from now on fits into int32 unchanged
+	// |h6| <= 2^25; from now on fits into int32 unchanged
+	// |h3| <= 1.51*2^58
+	// |h7| <= 1.51*2^58
+
+	carry[3] = (h3 + (1 << 24)) >> 25
+	h4 += carry[3]
+	h3 -= carry[3] << 25
+	carry[7] = (h7 + (1 << 24)) >> 25
+	h8 += carry[7]
+	h7 -= carry[7] << 25
+	// |h3| <= 2^24; from now on fits into int32 unchanged
+	// |h7| <= 2^24; from now on fits into int32 unchanged
+	// |h4| <= 1.52*2^33
+	// |h8| <= 1.52*2^33
+
+	carry[4] = (h4 + (1 << 25)) >> 26
+	h5 += carry[4]
+	h4 -= carry[4] << 26
+	carry[8] = (h8 + (1 << 25)) >> 26
+	h9 += carry[8]
+	h8 -= carry[8] << 26
+	// |h4| <= 2^25; from now on fits into int32 unchanged
+	// |h8| <= 2^25; from now on fits into int32 unchanged
+	// |h5| <= 1.01*2^24
+	// |h9| <= 1.51*2^58
+
+	carry[9] = (h9 + (1 << 24)) >> 25
+	h0 += carry[9] * 19
+	h9 -= carry[9] << 25
+	// |h9| <= 2^24; from now on fits into int32 unchanged
+	// |h0| <= 1.8*2^37
+
+	carry[0] = (h0 + (1 << 25)) >> 26
+	h1 += carry[0]
+	h0 -= carry[0] << 26
+	// |h0| <= 2^25; from now on fits into int32 unchanged
+	// |h1| <= 1.01*2^24
+
+	h[0] = int32(h0)
+	h[1] = int32(h1)
+	h[2] = int32(h2)
+	h[3] = int32(h3)
+	h[4] = int32(h4)
+	h[5] = int32(h5)
+	h[6] = int32(h6)
+	h[7] = int32(h7)
+	h[8] = int32(h8)
+	h[9] = int32(h9)
+}
+
+// feSquare calculates h = f*f. Can overlap h with f.
+//
+// Preconditions:
+//    |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
+//
+// Postconditions:
+//    |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
+func feSquare(h, f *fieldElement) {
+	f0 := f[0]
+	f1 := f[1]
+	f2 := f[2]
+	f3 := f[3]
+	f4 := f[4]
+	f5 := f[5]
+	f6 := f[6]
+	f7 := f[7]
+	f8 := f[8]
+	f9 := f[9]
+	f0_2 := 2 * f0
+	f1_2 := 2 * f1
+	f2_2 := 2 * f2
+	f3_2 := 2 * f3
+	f4_2 := 2 * f4
+	f5_2 := 2 * f5
+	f6_2 := 2 * f6
+	f7_2 := 2 * f7
+	f5_38 := 38 * f5 // 1.31*2^30
+	f6_19 := 19 * f6 // 1.31*2^30
+	f7_38 := 38 * f7 // 1.31*2^30
+	f8_19 := 19 * f8 // 1.31*2^30
+	f9_38 := 38 * f9 // 1.31*2^30
+	f0f0 := int64(f0) * int64(f0)
+	f0f1_2 := int64(f0_2) * int64(f1)
+	f0f2_2 := int64(f0_2) * int64(f2)
+	f0f3_2 := int64(f0_2) * int64(f3)
+	f0f4_2 := int64(f0_2) * int64(f4)
+	f0f5_2 := int64(f0_2) * int64(f5)
+	f0f6_2 := int64(f0_2) * int64(f6)
+	f0f7_2 := int64(f0_2) * int64(f7)
+	f0f8_2 := int64(f0_2) * int64(f8)
+	f0f9_2 := int64(f0_2) * int64(f9)
+	f1f1_2 := int64(f1_2) * int64(f1)
+	f1f2_2 := int64(f1_2) * int64(f2)
+	f1f3_4 := int64(f1_2) * int64(f3_2)
+	f1f4_2 := int64(f1_2) * int64(f4)
+	f1f5_4 := int64(f1_2) * int64(f5_2)
+	f1f6_2 := int64(f1_2) * int64(f6)
+	f1f7_4 := int64(f1_2) * int64(f7_2)
+	f1f8_2 := int64(f1_2) * int64(f8)
+	f1f9_76 := int64(f1_2) * int64(f9_38)
+	f2f2 := int64(f2) * int64(f2)
+	f2f3_2 := int64(f2_2) * int64(f3)
+	f2f4_2 := int64(f2_2) * int64(f4)
+	f2f5_2 := int64(f2_2) * int64(f5)
+	f2f6_2 := int64(f2_2) * int64(f6)
+	f2f7_2 := int64(f2_2) * int64(f7)
+	f2f8_38 := int64(f2_2) * int64(f8_19)
+	f2f9_38 := int64(f2) * int64(f9_38)
+	f3f3_2 := int64(f3_2) * int64(f3)
+	f3f4_2 := int64(f3_2) * int64(f4)
+	f3f5_4 := int64(f3_2) * int64(f5_2)
+	f3f6_2 := int64(f3_2) * int64(f6)
+	f3f7_76 := int64(f3_2) * int64(f7_38)
+	f3f8_38 := int64(f3_2) * int64(f8_19)
+	f3f9_76 := int64(f3_2) * int64(f9_38)
+	f4f4 := int64(f4) * int64(f4)
+	f4f5_2 := int64(f4_2) * int64(f5)
+	f4f6_38 := int64(f4_2) * int64(f6_19)
+	f4f7_38 := int64(f4) * int64(f7_38)
+	f4f8_38 := int64(f4_2) * int64(f8_19)
+	f4f9_38 := int64(f4) * int64(f9_38)
+	f5f5_38 := int64(f5) * int64(f5_38)
+	f5f6_38 := int64(f5_2) * int64(f6_19)
+	f5f7_76 := int64(f5_2) * int64(f7_38)
+	f5f8_38 := int64(f5_2) * int64(f8_19)
+	f5f9_76 := int64(f5_2) * int64(f9_38)
+	f6f6_19 := int64(f6) * int64(f6_19)
+	f6f7_38 := int64(f6) * int64(f7_38)
+	f6f8_38 := int64(f6_2) * int64(f8_19)
+	f6f9_38 := int64(f6) * int64(f9_38)
+	f7f7_38 := int64(f7) * int64(f7_38)
+	f7f8_38 := int64(f7_2) * int64(f8_19)
+	f7f9_76 := int64(f7_2) * int64(f9_38)
+	f8f8_19 := int64(f8) * int64(f8_19)
+	f8f9_38 := int64(f8) * int64(f9_38)
+	f9f9_38 := int64(f9) * int64(f9_38)
+	h0 := f0f0 + f1f9_76 + f2f8_38 + f3f7_76 + f4f6_38 + f5f5_38
+	h1 := f0f1_2 + f2f9_38 + f3f8_38 + f4f7_38 + f5f6_38
+	h2 := f0f2_2 + f1f1_2 + f3f9_76 + f4f8_38 + f5f7_76 + f6f6_19
+	h3 := f0f3_2 + f1f2_2 + f4f9_38 + f5f8_38 + f6f7_38
+	h4 := f0f4_2 + f1f3_4 + f2f2 + f5f9_76 + f6f8_38 + f7f7_38
+	h5 := f0f5_2 + f1f4_2 + f2f3_2 + f6f9_38 + f7f8_38
+	h6 := f0f6_2 + f1f5_4 + f2f4_2 + f3f3_2 + f7f9_76 + f8f8_19
+	h7 := f0f7_2 + f1f6_2 + f2f5_2 + f3f4_2 + f8f9_38
+	h8 := f0f8_2 + f1f7_4 + f2f6_2 + f3f5_4 + f4f4 + f9f9_38
+	h9 := f0f9_2 + f1f8_2 + f2f7_2 + f3f6_2 + f4f5_2
+	var carry [10]int64
+
+	carry[0] = (h0 + (1 << 25)) >> 26
+	h1 += carry[0]
+	h0 -= carry[0] << 26
+	carry[4] = (h4 + (1 << 25)) >> 26
+	h5 += carry[4]
+	h4 -= carry[4] << 26
+
+	carry[1] = (h1 + (1 << 24)) >> 25
+	h2 += carry[1]
+	h1 -= carry[1] << 25
+	carry[5] = (h5 + (1 << 24)) >> 25
+	h6 += carry[5]
+	h5 -= carry[5] << 25
+
+	carry[2] = (h2 + (1 << 25)) >> 26
+	h3 += carry[2]
+	h2 -= carry[2] << 26
+	carry[6] = (h6 + (1 << 25)) >> 26
+	h7 += carry[6]
+	h6 -= carry[6] << 26
+
+	carry[3] = (h3 + (1 << 24)) >> 25
+	h4 += carry[3]
+	h3 -= carry[3] << 25
+	carry[7] = (h7 + (1 << 24)) >> 25
+	h8 += carry[7]
+	h7 -= carry[7] << 25
+
+	carry[4] = (h4 + (1 << 25)) >> 26
+	h5 += carry[4]
+	h4 -= carry[4] << 26
+	carry[8] = (h8 + (1 << 25)) >> 26
+	h9 += carry[8]
+	h8 -= carry[8] << 26
+
+	carry[9] = (h9 + (1 << 24)) >> 25
+	h0 += carry[9] * 19
+	h9 -= carry[9] << 25
+
+	carry[0] = (h0 + (1 << 25)) >> 26
+	h1 += carry[0]
+	h0 -= carry[0] << 26
+
+	h[0] = int32(h0)
+	h[1] = int32(h1)
+	h[2] = int32(h2)
+	h[3] = int32(h3)
+	h[4] = int32(h4)
+	h[5] = int32(h5)
+	h[6] = int32(h6)
+	h[7] = int32(h7)
+	h[8] = int32(h8)
+	h[9] = int32(h9)
+}
+
+// feMul121666 calculates h = f * 121666. Can overlap h with f.
+//
+// Preconditions:
+//    |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
+//
+// Postconditions:
+//    |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
+func feMul121666(h, f *fieldElement) {
+	h0 := int64(f[0]) * 121666
+	h1 := int64(f[1]) * 121666
+	h2 := int64(f[2]) * 121666
+	h3 := int64(f[3]) * 121666
+	h4 := int64(f[4]) * 121666
+	h5 := int64(f[5]) * 121666
+	h6 := int64(f[6]) * 121666
+	h7 := int64(f[7]) * 121666
+	h8 := int64(f[8]) * 121666
+	h9 := int64(f[9]) * 121666
+	var carry [10]int64
+
+	carry[9] = (h9 + (1 << 24)) >> 25
+	h0 += carry[9] * 19
+	h9 -= carry[9] << 25
+	carry[1] = (h1 + (1 << 24)) >> 25
+	h2 += carry[1]
+	h1 -= carry[1] << 25
+	carry[3] = (h3 + (1 << 24)) >> 25
+	h4 += carry[3]
+	h3 -= carry[3] << 25
+	carry[5] = (h5 + (1 << 24)) >> 25
+	h6 += carry[5]
+	h5 -= carry[5] << 25
+	carry[7] = (h7 + (1 << 24)) >> 25
+	h8 += carry[7]
+	h7 -= carry[7] << 25
+
+	carry[0] = (h0 + (1 << 25)) >> 26
+	h1 += carry[0]
+	h0 -= carry[0] << 26
+	carry[2] = (h2 + (1 << 25)) >> 26
+	h3 += carry[2]
+	h2 -= carry[2] << 26
+	carry[4] = (h4 + (1 << 25)) >> 26
+	h5 += carry[4]
+	h4 -= carry[4] << 26
+	carry[6] = (h6 + (1 << 25)) >> 26
+	h7 += carry[6]
+	h6 -= carry[6] << 26
+	carry[8] = (h8 + (1 << 25)) >> 26
+	h9 += carry[8]
+	h8 -= carry[8] << 26
+
+	h[0] = int32(h0)
+	h[1] = int32(h1)
+	h[2] = int32(h2)
+	h[3] = int32(h3)
+	h[4] = int32(h4)
+	h[5] = int32(h5)
+	h[6] = int32(h6)
+	h[7] = int32(h7)
+	h[8] = int32(h8)
+	h[9] = int32(h9)
+}
+
+// feInvert sets out = z^-1.
+func feInvert(out, z *fieldElement) {
+	var t0, t1, t2, t3 fieldElement
+	var i int
+
+	feSquare(&t0, z)
+	for i = 1; i < 1; i++ {
+		feSquare(&t0, &t0)
+	}
+	feSquare(&t1, &t0)
+	for i = 1; i < 2; i++ {
+		feSquare(&t1, &t1)
+	}
+	feMul(&t1, z, &t1)
+	feMul(&t0, &t0, &t1)
+	feSquare(&t2, &t0)
+	for i = 1; i < 1; i++ {
+		feSquare(&t2, &t2)
+	}
+	feMul(&t1, &t1, &t2)
+	feSquare(&t2, &t1)
+	for i = 1; i < 5; i++ {
+		feSquare(&t2, &t2)
+	}
+	feMul(&t1, &t2, &t1)
+	feSquare(&t2, &t1)
+	for i = 1; i < 10; i++ {
+		feSquare(&t2, &t2)
+	}
+	feMul(&t2, &t2, &t1)
+	feSquare(&t3, &t2)
+	for i = 1; i < 20; i++ {
+		feSquare(&t3, &t3)
+	}
+	feMul(&t2, &t3, &t2)
+	feSquare(&t2, &t2)
+	for i = 1; i < 10; i++ {
+		feSquare(&t2, &t2)
+	}
+	feMul(&t1, &t2, &t1)
+	feSquare(&t2, &t1)
+	for i = 1; i < 50; i++ {
+		feSquare(&t2, &t2)
+	}
+	feMul(&t2, &t2, &t1)
+	feSquare(&t3, &t2)
+	for i = 1; i < 100; i++ {
+		feSquare(&t3, &t3)
+	}
+	feMul(&t2, &t3, &t2)
+	feSquare(&t2, &t2)
+	for i = 1; i < 50; i++ {
+		feSquare(&t2, &t2)
+	}
+	feMul(&t1, &t2, &t1)
+	feSquare(&t1, &t1)
+	for i = 1; i < 5; i++ {
+		feSquare(&t1, &t1)
+	}
+	feMul(out, &t1, &t0)
+}
+
+func scalarMult(out, in, base *[32]byte) {
+	var e [32]byte
+
+	copy(e[:], in[:])
+	e[0] &= 248
+	e[31] &= 127
+	e[31] |= 64
+
+	var x1, x2, z2, x3, z3, tmp0, tmp1 fieldElement
+	feFromBytes(&x1, base)
+	feOne(&x2)
+	feCopy(&x3, &x1)
+	feOne(&z3)
+
+	swap := int32(0)
+	for pos := 254; pos >= 0; pos-- {
+		b := e[pos/8] >> uint(pos&7)
+		b &= 1
+		swap ^= int32(b)
+		feCSwap(&x2, &x3, swap)
+		feCSwap(&z2, &z3, swap)
+		swap = int32(b)
+
+		feSub(&tmp0, &x3, &z3)
+		feSub(&tmp1, &x2, &z2)
+		feAdd(&x2, &x2, &z2)
+		feAdd(&z2, &x3, &z3)
+		feMul(&z3, &tmp0, &x2)
+		feMul(&z2, &z2, &tmp1)
+		feSquare(&tmp0, &tmp1)
+		feSquare(&tmp1, &x2)
+		feAdd(&x3, &z3, &z2)
+		feSub(&z2, &z3, &z2)
+		feMul(&x2, &tmp1, &tmp0)
+		feSub(&tmp1, &tmp1, &tmp0)
+		feSquare(&z2, &z2)
+		feMul121666(&z3, &tmp1)
+		feSquare(&x3, &x3)
+		feAdd(&tmp0, &tmp0, &z3)
+		feMul(&z3, &x1, &z2)
+		feMul(&z2, &tmp1, &tmp0)
+	}
+
+	feCSwap(&x2, &x3, swap)
+	feCSwap(&z2, &z3, swap)
+
+	feInvert(&z2, &z2)
+	feMul(&x2, &x2, &z2)
+	feToBytes(out, &x2)
+}

vendor/github.com/keybase/go-crypto/curve25519/curve_impl.go

@@ -0,0 +1,113 @@
+package curve25519
+
+import (
+	"crypto/elliptic"
+	"math/big"
+	"sync"
+)
+
+var cv25519 cv25519Curve
+
+type cv25519Curve struct {
+	*elliptic.CurveParams
+}
+
+func copyReverse(dst []byte, src []byte) {
+	// Curve 25519 multiplication functions expect scalars in reverse
+	// order than PGP. To keep the curve25519Curve type consistent
+	// with other curves, we reverse it here.
+	for i, j := 0, len(src)-1; j >= 0; i, j = i+1, j-1 {
+		dst[i] = src[j]
+	}
+}
+
+func (cv25519Curve) ScalarMult(x1, y1 *big.Int, scalar []byte) (x, y *big.Int) {
+	// Assume y1 is 0 with cv25519.
+	var dst [32]byte
+	var x1Bytes [32]byte
+	var scalarBytes [32]byte
+
+	copy(x1Bytes[:], x1.Bytes()[:32])
+	copyReverse(scalarBytes[:], scalar[:32])
+
+	scalarMult(&dst, &scalarBytes, &x1Bytes)
+
+	x = new(big.Int).SetBytes(dst[:])
+	y = new(big.Int)
+	return x, y
+}
+
+func (cv25519Curve) ScalarBaseMult(scalar []byte) (x, y *big.Int) {
+	var dst [32]byte
+	var scalarBytes [32]byte
+	copyReverse(scalarBytes[:], scalar[:32])
+	scalarMult(&dst, &scalarBytes, &basePoint)
+	x = new(big.Int).SetBytes(dst[:])
+	y = new(big.Int)
+	return x, y
+}
+
+func (cv25519Curve) IsOnCurve(bigX, bigY *big.Int) bool {
+	return bigY.Sign() == 0 // bigY == 0 ?
+}
+
+// More information about 0x40 point format:
+// https://tools.ietf.org/html/draft-koch-eddsa-for-openpgp-00#section-3
+// In addition to uncompressed point format described here:
+// https://tools.ietf.org/html/rfc6637#section-6
+
+func (cv25519Curve) MarshalType40(x, y *big.Int) []byte {
+	byteLen := 32
+
+	ret := make([]byte, 1+byteLen)
+	ret[0] = 0x40
+
+	xBytes := x.Bytes()
+	copy(ret[1+byteLen-len(xBytes):], xBytes)
+	return ret
+}
+
+func (cv25519Curve) UnmarshalType40(data []byte) (x, y *big.Int) {
+	if len(data) != 1+32 {
+		return nil, nil
+	}
+	if data[0] != 0x40 {
+		return nil, nil
+	}
+	x = new(big.Int).SetBytes(data[1:])
+	// Any x is a valid curve point.
+	return x, new(big.Int)
+}
+
+// ToCurve25519 casts given elliptic.Curve type to Curve25519 type, or
+// returns nil, false if cast was unsuccessful.
+func ToCurve25519(cv elliptic.Curve) (cv25519Curve, bool) {
+	cv2, ok := cv.(cv25519Curve)
+	return cv2, ok
+}
+
+func initCv25519() {
+	cv25519.CurveParams = &elliptic.CurveParams{Name: "Curve 25519"}
+	// Some code relies on these parameters being available for
+	// checking Curve coordinate length. They should not be used
+	// directly for any calculations.
+	cv25519.P, _ = new (big.Int).SetString("7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffed", 16)
+	cv25519.N, _ = new (big.Int).SetString("1000000000000000000000000000000014def9dea2f79cd65812631a5cf5d3ed", 16)
+	cv25519.Gx, _ = new (big.Int).SetString("9", 16)
+	cv25519.Gy, _ = new (big.Int).SetString("20ae19a1b8a086b4e01edd2c7748d14c923d4d7e6d7c61b229e9c5a27eced3d9", 16)
+	cv25519.BitSize = 256
+}
+
+var initonce sync.Once
+
+// Cv25519 returns a Curve which (partially) implements Cv25519. Only
+// ScalarMult and ScalarBaseMult are valid for this curve. Add and
+// Double should not be used.
+func Cv25519() elliptic.Curve {
+	initonce.Do(initCv25519)
+	return cv25519
+}
+
+func (curve cv25519Curve) Params() *elliptic.CurveParams {
+	return curve.CurveParams
+}

vendor/github.com/keybase/go-crypto/curve25519/doc.go

@@ -0,0 +1,23 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package curve25519 provides an implementation of scalar multiplication on
+// the elliptic curve known as curve25519. See http://cr.yp.to/ecdh.html
+package curve25519
+
+// basePoint is the x coordinate of the generator of the curve.
+var basePoint = [32]byte{9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+
+// ScalarMult sets dst to the product in*base where dst and base are the x
+// coordinates of group points and all values are in little-endian form.
+func ScalarMult(dst, in, base *[32]byte) {
+	scalarMult(dst, in, base)
+}
+
+// ScalarBaseMult sets dst to the product in*base where dst and base are the x
+// coordinates of group points, base is the standard generator and all values
+// are in little-endian form.
+func ScalarBaseMult(dst, in *[32]byte) {
+	ScalarMult(dst, in, &basePoint)
+}

vendor/github.com/keybase/go-crypto/curve25519/freeze_amd64.s

@@ -0,0 +1,94 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This code was translated into a form compatible with 6a from the public
+// domain sources in SUPERCOP: http://bench.cr.yp.to/supercop.html
+
+// +build amd64,!gccgo,!appengine
+
+// func freeze(inout *[5]uint64)
+TEXT ·freeze(SB),7,$96-8
+	MOVQ inout+0(FP), DI
+
+	MOVQ SP,R11
+	MOVQ $31,CX
+	NOTQ CX
+	ANDQ CX,SP
+	ADDQ $32,SP
+
+	MOVQ R11,0(SP)
+	MOVQ R12,8(SP)
+	MOVQ R13,16(SP)
+	MOVQ R14,24(SP)
+	MOVQ R15,32(SP)
+	MOVQ BX,40(SP)
+	MOVQ BP,48(SP)
+	MOVQ 0(DI),SI
+	MOVQ 8(DI),DX
+	MOVQ 16(DI),CX
+	MOVQ 24(DI),R8
+	MOVQ 32(DI),R9
+	MOVQ ·REDMASK51(SB),AX
+	MOVQ AX,R10
+	SUBQ $18,R10
+	MOVQ $3,R11
+REDUCELOOP:
+	MOVQ SI,R12
+	SHRQ $51,R12
+	ANDQ AX,SI
+	ADDQ R12,DX
+	MOVQ DX,R12
+	SHRQ $51,R12
+	ANDQ AX,DX
+	ADDQ R12,CX
+	MOVQ CX,R12
+	SHRQ $51,R12
+	ANDQ AX,CX
+	ADDQ R12,R8
+	MOVQ R8,R12
+	SHRQ $51,R12
+	ANDQ AX,R8
+	ADDQ R12,R9
+	MOVQ R9,R12
+	SHRQ $51,R12
+	ANDQ AX,R9
+	IMUL3Q $19,R12,R12
+	ADDQ R12,SI
+	SUBQ $1,R11
+	JA REDUCELOOP
+	MOVQ $1,R12
+	CMPQ R10,SI
+	CMOVQLT R11,R12
+	CMPQ AX,DX
+	CMOVQNE R11,R12
+	CMPQ AX,CX
+	CMOVQNE R11,R12
+	CMPQ AX,R8
+	CMOVQNE R11,R12
+	CMPQ AX,R9
+	CMOVQNE R11,R12
+	NEGQ R12
+	ANDQ R12,AX
+	ANDQ R12,R10
+	SUBQ R10,SI
+	SUBQ AX,DX
+	SUBQ AX,CX
+	SUBQ AX,R8
+	SUBQ AX,R9
+	MOVQ SI,0(DI)
+	MOVQ DX,8(DI)
+	MOVQ CX,16(DI)
+	MOVQ R8,24(DI)
+	MOVQ R9,32(DI)
+	MOVQ 0(SP),R11
+	MOVQ 8(SP),R12
+	MOVQ 16(SP),R13
+	MOVQ 24(SP),R14
+	MOVQ 32(SP),R15
+	MOVQ 40(SP),BX
+	MOVQ 48(SP),BP
+	MOVQ R11,SP
+	MOVQ DI,AX
+	MOVQ SI,DX
+	RET

vendor/github.com/keybase/go-crypto/curve25519/mont25519_amd64.go

@@ -0,0 +1,240 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build amd64,!gccgo,!appengine
+
+package curve25519
+
+// These functions are implemented in the .s files. The names of the functions
+// in the rest of the file are also taken from the SUPERCOP sources to help
+// people following along.
+
+//go:noescape
+
+func cswap(inout *[5]uint64, v uint64)
+
+//go:noescape
+
+func ladderstep(inout *[5][5]uint64)
+
+//go:noescape
+
+func freeze(inout *[5]uint64)
+
+//go:noescape
+
+func mul(dest, a, b *[5]uint64)
+
+//go:noescape
+
+func square(out, in *[5]uint64)
+
+// mladder uses a Montgomery ladder to calculate (xr/zr) *= s.
+func mladder(xr, zr *[5]uint64, s *[32]byte) {
+	var work [5][5]uint64
+
+	work[0] = *xr
+	setint(&work[1], 1)
+	setint(&work[2], 0)
+	work[3] = *xr
+	setint(&work[4], 1)
+
+	j := uint(6)
+	var prevbit byte
+
+	for i := 31; i >= 0; i-- {
+		for j < 8 {
+			bit := ((*s)[i] >> j) & 1
+			swap := bit ^ prevbit
+			prevbit = bit
+			cswap(&work[1], uint64(swap))
+			ladderstep(&work)
+			j--
+		}
+		j = 7
+	}
+
+	*xr = work[1]
+	*zr = work[2]
+}
+
+func scalarMult(out, in, base *[32]byte) {
+	var e [32]byte
+	copy(e[:], (*in)[:])
+	e[0] &= 248
+	e[31] &= 127
+	e[31] |= 64
+
+	var t, z [5]uint64
+	unpack(&t, base)
+	mladder(&t, &z, &e)
+	invert(&z, &z)
+	mul(&t, &t, &z)
+	pack(out, &t)
+}
+
+func setint(r *[5]uint64, v uint64) {
+	r[0] = v
+	r[1] = 0
+	r[2] = 0
+	r[3] = 0
+	r[4] = 0
+}
+
+// unpack sets r = x where r consists of 5, 51-bit limbs in little-endian
+// order.
+func unpack(r *[5]uint64, x *[32]byte) {
+	r[0] = uint64(x[0]) |
+		uint64(x[1])<<8 |
+		uint64(x[2])<<16 |
+		uint64(x[3])<<24 |
+		uint64(x[4])<<32 |
+		uint64(x[5])<<40 |
+		uint64(x[6]&7)<<48
+
+	r[1] = uint64(x[6])>>3 |
+		uint64(x[7])<<5 |
+		uint64(x[8])<<13 |
+		uint64(x[9])<<21 |
+		uint64(x[10])<<29 |
+		uint64(x[11])<<37 |
+		uint64(x[12]&63)<<45
+
+	r[2] = uint64(x[12])>>6 |
+		uint64(x[13])<<2 |
+		uint64(x[14])<<10 |
+		uint64(x[15])<<18 |
+		uint64(x[16])<<26 |
+		uint64(x[17])<<34 |
+		uint64(x[18])<<42 |
+		uint64(x[19]&1)<<50
+
+	r[3] = uint64(x[19])>>1 |
+		uint64(x[20])<<7 |
+		uint64(x[21])<<15 |
+		uint64(x[22])<<23 |
+		uint64(x[23])<<31 |
+		uint64(x[24])<<39 |
+		uint64(x[25]&15)<<47
+
+	r[4] = uint64(x[25])>>4 |
+		uint64(x[26])<<4 |
+		uint64(x[27])<<12 |
+		uint64(x[28])<<20 |
+		uint64(x[29])<<28 |
+		uint64(x[30])<<36 |
+		uint64(x[31]&127)<<44
+}
+
+// pack sets out = x where out is the usual, little-endian form of the 5,
+// 51-bit limbs in x.
+func pack(out *[32]byte, x *[5]uint64) {
+	t := *x
+	freeze(&t)
+
+	out[0] = byte(t[0])
+	out[1] = byte(t[0] >> 8)
+	out[2] = byte(t[0] >> 16)
+	out[3] = byte(t[0] >> 24)
+	out[4] = byte(t[0] >> 32)
+	out[5] = byte(t[0] >> 40)
+	out[6] = byte(t[0] >> 48)
+
+	out[6] ^= byte(t[1]<<3) & 0xf8
+	out[7] = byte(t[1] >> 5)
+	out[8] = byte(t[1] >> 13)
+	out[9] = byte(t[1] >> 21)
+	out[10] = byte(t[1] >> 29)
+	out[11] = byte(t[1] >> 37)
+	out[12] = byte(t[1] >> 45)
+
+	out[12] ^= byte(t[2]<<6) & 0xc0
+	out[13] = byte(t[2] >> 2)
+	out[14] = byte(t[2] >> 10)
+	out[15] = byte(t[2] >> 18)
+	out[16] = byte(t[2] >> 26)
+	out[17] = byte(t[2] >> 34)
+	out[18] = byte(t[2] >> 42)
+	out[19] = byte(t[2] >> 50)
+
+	out[19] ^= byte(t[3]<<1) & 0xfe
+	out[20] = byte(t[3] >> 7)
+	out[21] = byte(t[3] >> 15)
+	out[22] = byte(t[3] >> 23)
+	out[23] = byte(t[3] >> 31)
+	out[24] = byte(t[3] >> 39)
+	out[25] = byte(t[3] >> 47)
+
+	out[25] ^= byte(t[4]<<4) & 0xf0
+	out[26] = byte(t[4] >> 4)
+	out[27] = byte(t[4] >> 12)
+	out[28] = byte(t[4] >> 20)
+	out[29] = byte(t[4] >> 28)
+	out[30] = byte(t[4] >> 36)
+	out[31] = byte(t[4] >> 44)
+}
+
+// invert calculates r = x^-1 mod p using Fermat's little theorem.
+func invert(r *[5]uint64, x *[5]uint64) {
+	var z2, z9, z11, z2_5_0, z2_10_0, z2_20_0, z2_50_0, z2_100_0, t [5]uint64
+
+	square(&z2, x)        /* 2 */
+	square(&t, &z2)       /* 4 */
+	square(&t, &t)        /* 8 */
+	mul(&z9, &t, x)       /* 9 */
+	mul(&z11, &z9, &z2)   /* 11 */
+	square(&t, &z11)      /* 22 */
+	mul(&z2_5_0, &t, &z9) /* 2^5 - 2^0 = 31 */
+
+	square(&t, &z2_5_0)      /* 2^6 - 2^1 */
+	for i := 1; i < 5; i++ { /* 2^20 - 2^10 */
+		square(&t, &t)
+	}
+	mul(&z2_10_0, &t, &z2_5_0) /* 2^10 - 2^0 */
+
+	square(&t, &z2_10_0)      /* 2^11 - 2^1 */
+	for i := 1; i < 10; i++ { /* 2^20 - 2^10 */
+		square(&t, &t)
+	}
+	mul(&z2_20_0, &t, &z2_10_0) /* 2^20 - 2^0 */
+
+	square(&t, &z2_20_0)      /* 2^21 - 2^1 */
+	for i := 1; i < 20; i++ { /* 2^40 - 2^20 */
+		square(&t, &t)
+	}
+	mul(&t, &t, &z2_20_0) /* 2^40 - 2^0 */
+
+	square(&t, &t)            /* 2^41 - 2^1 */
+	for i := 1; i < 10; i++ { /* 2^50 - 2^10 */
+		square(&t, &t)
+	}
+	mul(&z2_50_0, &t, &z2_10_0) /* 2^50 - 2^0 */
+
+	square(&t, &z2_50_0)      /* 2^51 - 2^1 */
+	for i := 1; i < 50; i++ { /* 2^100 - 2^50 */
+		square(&t, &t)
+	}
+	mul(&z2_100_0, &t, &z2_50_0) /* 2^100 - 2^0 */
+
+	square(&t, &z2_100_0)      /* 2^101 - 2^1 */
+	for i := 1; i < 100; i++ { /* 2^200 - 2^100 */
+		square(&t, &t)
+	}
+	mul(&t, &t, &z2_100_0) /* 2^200 - 2^0 */
+
+	square(&t, &t)            /* 2^201 - 2^1 */
+	for i := 1; i < 50; i++ { /* 2^250 - 2^50 */
+		square(&t, &t)
+	}
+	mul(&t, &t, &z2_50_0) /* 2^250 - 2^0 */
+
+	square(&t, &t) /* 2^251 - 2^1 */
+	square(&t, &t) /* 2^252 - 2^2 */
+	square(&t, &t) /* 2^253 - 2^3 */
+
+	square(&t, &t) /* 2^254 - 2^4 */
+
+	square(&t, &t)   /* 2^255 - 2^5 */
+	mul(r, &t, &z11) /* 2^255 - 21 */
+}

vendor/github.com/keybase/go-crypto/curve25519/mul_amd64.s

@@ -0,0 +1,191 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This code was translated into a form compatible with 6a from the public
+// domain sources in SUPERCOP: http://bench.cr.yp.to/supercop.html
+
+// +build amd64,!gccgo,!appengine
+
+// func mul(dest, a, b *[5]uint64)
+TEXT ·mul(SB),0,$128-24
+	MOVQ dest+0(FP), DI
+	MOVQ a+8(FP), SI
+	MOVQ b+16(FP), DX
+
+	MOVQ SP,R11
+	MOVQ $31,CX
+	NOTQ CX
+	ANDQ CX,SP
+	ADDQ $32,SP
+
+	MOVQ R11,0(SP)
+	MOVQ R12,8(SP)
+	MOVQ R13,16(SP)
+	MOVQ R14,24(SP)
+	MOVQ R15,32(SP)
+	MOVQ BX,40(SP)
+	MOVQ BP,48(SP)
+	MOVQ DI,56(SP)
+	MOVQ DX,CX
+	MOVQ 24(SI),DX
+	IMUL3Q $19,DX,AX
+	MOVQ AX,64(SP)
+	MULQ 16(CX)
+	MOVQ AX,R8
+	MOVQ DX,R9
+	MOVQ 32(SI),DX
+	IMUL3Q $19,DX,AX
+	MOVQ AX,72(SP)
+	MULQ 8(CX)
+	ADDQ AX,R8
+	ADCQ DX,R9
+	MOVQ 0(SI),AX
+	MULQ 0(CX)
+	ADDQ AX,R8
+	ADCQ DX,R9
+	MOVQ 0(SI),AX
+	MULQ 8(CX)
+	MOVQ AX,R10
+	MOVQ DX,R11
+	MOVQ 0(SI),AX
+	MULQ 16(CX)
+	MOVQ AX,R12
+	MOVQ DX,R13
+	MOVQ 0(SI),AX
+	MULQ 24(CX)
+	MOVQ AX,R14
+	MOVQ DX,R15
+	MOVQ 0(SI),AX
+	MULQ 32(CX)
+	MOVQ AX,BX
+	MOVQ DX,BP
+	MOVQ 8(SI),AX
+	MULQ 0(CX)
+	ADDQ AX,R10
+	ADCQ DX,R11
+	MOVQ 8(SI),AX
+	MULQ 8(CX)
+	ADDQ AX,R12
+	ADCQ DX,R13
+	MOVQ 8(SI),AX
+	MULQ 16(CX)
+	ADDQ AX,R14
+	ADCQ DX,R15
+	MOVQ 8(SI),AX
+	MULQ 24(CX)
+	ADDQ AX,BX
+	ADCQ DX,BP
+	MOVQ 8(SI),DX
+	IMUL3Q $19,DX,AX
+	MULQ 32(CX)
+	ADDQ AX,R8
+	ADCQ DX,R9
+	MOVQ 16(SI),AX
+	MULQ 0(CX)
+	ADDQ AX,R12
+	ADCQ DX,R13
+	MOVQ 16(SI),AX
+	MULQ 8(CX)
+	ADDQ AX,R14
+	ADCQ DX,R15
+	MOVQ 16(SI),AX
+	MULQ 16(CX)
+	ADDQ AX,BX
+	ADCQ DX,BP
+	MOVQ 16(SI),DX
+	IMUL3Q $19,DX,AX
+	MULQ 24(CX)
+	ADDQ AX,R8
+	ADCQ DX,R9
+	MOVQ 16(SI),DX
+	IMUL3Q $19,DX,AX
+	MULQ 32(CX)
+	ADDQ AX,R10
+	ADCQ DX,R11
+	MOVQ 24(SI),AX
+	MULQ 0(CX)
+	ADDQ AX,R14
+	ADCQ DX,R15
+	MOVQ 24(SI),AX
+	MULQ 8(CX)
+	ADDQ AX,BX
+	ADCQ DX,BP
+	MOVQ 64(SP),AX
+	MULQ 24(CX)
+	ADDQ AX,R10
+	ADCQ DX,R11
+	MOVQ 64(SP),AX
+	MULQ 32(CX)
+	ADDQ AX,R12
+	ADCQ DX,R13
+	MOVQ 32(SI),AX
+	MULQ 0(CX)
+	ADDQ AX,BX
+	ADCQ DX,BP
+	MOVQ 72(SP),AX
+	MULQ 16(CX)
+	ADDQ AX,R10
+	ADCQ DX,R11
+	MOVQ 72(SP),AX
+	MULQ 24(CX)
+	ADDQ AX,R12
+	ADCQ DX,R13
+	MOVQ 72(SP),AX
+	MULQ 32(CX)
+	ADDQ AX,R14
+	ADCQ DX,R15
+	MOVQ ·REDMASK51(SB),SI
+	SHLQ $13,R9:R8
+	ANDQ SI,R8
+	SHLQ $13,R11:R10
+	ANDQ SI,R10
+	ADDQ R9,R10
+	SHLQ $13,R13:R12
+	ANDQ SI,R12
+	ADDQ R11,R12
+	SHLQ $13,R15:R14
+	ANDQ SI,R14
+	ADDQ R13,R14
+	SHLQ $13,BP:BX
+	ANDQ SI,BX
+	ADDQ R15,BX
+	IMUL3Q $19,BP,DX
+	ADDQ DX,R8
+	MOVQ R8,DX
+	SHRQ $51,DX
+	ADDQ R10,DX
+	MOVQ DX,CX
+	SHRQ $51,DX
+	ANDQ SI,R8
+	ADDQ R12,DX
+	MOVQ DX,R9
+	SHRQ $51,DX
+	ANDQ SI,CX
+	ADDQ R14,DX
+	MOVQ DX,AX
+	SHRQ $51,DX
+	ANDQ SI,R9
+	ADDQ BX,DX
+	MOVQ DX,R10
+	SHRQ $51,DX
+	ANDQ SI,AX
+	IMUL3Q $19,DX,DX
+	ADDQ DX,R8
+	ANDQ SI,R10
+	MOVQ R8,0(DI)
+	MOVQ CX,8(DI)
+	MOVQ R9,16(DI)
+	MOVQ AX,24(DI)
+	MOVQ R10,32(DI)
+	MOVQ 0(SP),R11
+	MOVQ 8(SP),R12
+	MOVQ 16(SP),R13
+	MOVQ 24(SP),R14
+	MOVQ 32(SP),R15
+	MOVQ 40(SP),BX
+	MOVQ 48(SP),BP
+	MOVQ R11,SP
+	MOVQ DI,AX
+	MOVQ SI,DX
+	RET

vendor/github.com/keybase/go-crypto/curve25519/square_amd64.s

@@ -0,0 +1,153 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This code was translated into a form compatible with 6a from the public
+// domain sources in SUPERCOP: http://bench.cr.yp.to/supercop.html
+
+// +build amd64,!gccgo,!appengine
+
+// func square(out, in *[5]uint64)
+TEXT ·square(SB),7,$96-16
+	MOVQ out+0(FP), DI
+	MOVQ in+8(FP), SI
+
+	MOVQ SP,R11
+	MOVQ $31,CX
+	NOTQ CX
+	ANDQ CX,SP
+	ADDQ $32, SP
+
+	MOVQ R11,0(SP)
+	MOVQ R12,8(SP)
+	MOVQ R13,16(SP)
+	MOVQ R14,24(SP)
+	MOVQ R15,32(SP)
+	MOVQ BX,40(SP)
+	MOVQ BP,48(SP)
+	MOVQ 0(SI),AX
+	MULQ 0(SI)
+	MOVQ AX,CX
+	MOVQ DX,R8
+	MOVQ 0(SI),AX
+	SHLQ $1,AX
+	MULQ 8(SI)
+	MOVQ AX,R9
+	MOVQ DX,R10
+	MOVQ 0(SI),AX
+	SHLQ $1,AX
+	MULQ 16(SI)
+	MOVQ AX,R11
+	MOVQ DX,R12
+	MOVQ 0(SI),AX
+	SHLQ $1,AX
+	MULQ 24(SI)
+	MOVQ AX,R13
+	MOVQ DX,R14
+	MOVQ 0(SI),AX
+	SHLQ $1,AX
+	MULQ 32(SI)
+	MOVQ AX,R15
+	MOVQ DX,BX
+	MOVQ 8(SI),AX
+	MULQ 8(SI)
+	ADDQ AX,R11
+	ADCQ DX,R12
+	MOVQ 8(SI),AX
+	SHLQ $1,AX
+	MULQ 16(SI)
+	ADDQ AX,R13
+	ADCQ DX,R14
+	MOVQ 8(SI),AX
+	SHLQ $1,AX
+	MULQ 24(SI)
+	ADDQ AX,R15
+	ADCQ DX,BX
+	MOVQ 8(SI),DX
+	IMUL3Q $38,DX,AX
+	MULQ 32(SI)
+	ADDQ AX,CX
+	ADCQ DX,R8
+	MOVQ 16(SI),AX
+	MULQ 16(SI)
+	ADDQ AX,R15
+	ADCQ DX,BX
+	MOVQ 16(SI),DX
+	IMUL3Q $38,DX,AX
+	MULQ 24(SI)
+	ADDQ AX,CX
+	ADCQ DX,R8
+	MOVQ 16(SI),DX
+	IMUL3Q $38,DX,AX
+	MULQ 32(SI)
+	ADDQ AX,R9
+	ADCQ DX,R10
+	MOVQ 24(SI),DX
+	IMUL3Q $19,DX,AX
+	MULQ 24(SI)
+	ADDQ AX,R9
+	ADCQ DX,R10
+	MOVQ 24(SI),DX
+	IMUL3Q $38,DX,AX
+	MULQ 32(SI)
+	ADDQ AX,R11
+	ADCQ DX,R12
+	MOVQ 32(SI),DX
+	IMUL3Q $19,DX,AX
+	MULQ 32(SI)
+	ADDQ AX,R13
+	ADCQ DX,R14
+	MOVQ ·REDMASK51(SB),SI
+	SHLQ $13,R8:CX
+	ANDQ SI,CX
+	SHLQ $13,R10:R9
+	ANDQ SI,R9
+	ADDQ R8,R9
+	SHLQ $13,R12:R11
+	ANDQ SI,R11
+	ADDQ R10,R11
+	SHLQ $13,R14:R13
+	ANDQ SI,R13
+	ADDQ R12,R13
+	SHLQ $13,BX:R15
+	ANDQ SI,R15
+	ADDQ R14,R15
+	IMUL3Q $19,BX,DX
+	ADDQ DX,CX
+	MOVQ CX,DX
+	SHRQ $51,DX
+	ADDQ R9,DX
+	ANDQ SI,CX
+	MOVQ DX,R8
+	SHRQ $51,DX
+	ADDQ R11,DX
+	ANDQ SI,R8
+	MOVQ DX,R9
+	SHRQ $51,DX
+	ADDQ R13,DX
+	ANDQ SI,R9
+	MOVQ DX,AX
+	SHRQ $51,DX
+	ADDQ R15,DX
+	ANDQ SI,AX
+	MOVQ DX,R10
+	SHRQ $51,DX
+	IMUL3Q $19,DX,DX
+	ADDQ DX,CX
+	ANDQ SI,R10
+	MOVQ CX,0(DI)
+	MOVQ R8,8(DI)
+	MOVQ R9,16(DI)
+	MOVQ AX,24(DI)
+	MOVQ R10,32(DI)
+	MOVQ 0(SP),R11
+	MOVQ 8(SP),R12
+	MOVQ 16(SP),R13
+	MOVQ 24(SP),R14
+	MOVQ 32(SP),R15
+	MOVQ 40(SP),BX
+	MOVQ 48(SP),BP
+	MOVQ R11,SP
+	MOVQ DI,AX
+	MOVQ SI,DX
+	RET

vendor/github.com/keybase/go-crypto/ed25519/ed25519.go

@@ -0,0 +1,181 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package ed25519 implements the Ed25519 signature algorithm. See
+// http://ed25519.cr.yp.to/.
+//
+// These functions are also compatible with the “Ed25519” function defined in
+// https://tools.ietf.org/html/draft-irtf-cfrg-eddsa-05.
+package ed25519
+
+// This code is a port of the public domain, “ref10” implementation of ed25519
+// from SUPERCOP.
+
+import (
+	"crypto"
+	cryptorand "crypto/rand"
+	"crypto/sha512"
+	"crypto/subtle"
+	"errors"
+	"io"
+	"strconv"
+
+	"github.com/keybase/go-crypto/ed25519/internal/edwards25519"
+)
+
+const (
+	// PublicKeySize is the size, in bytes, of public keys as used in this package.
+	PublicKeySize = 32
+	// PrivateKeySize is the size, in bytes, of private keys as used in this package.
+	PrivateKeySize = 64
+	// SignatureSize is the size, in bytes, of signatures generated and verified by this package.
+	SignatureSize = 64
+)
+
+// PublicKey is the type of Ed25519 public keys.
+type PublicKey []byte
+
+// PrivateKey is the type of Ed25519 private keys. It implements crypto.Signer.
+type PrivateKey []byte
+
+// Public returns the PublicKey corresponding to priv.
+func (priv PrivateKey) Public() crypto.PublicKey {
+	publicKey := make([]byte, PublicKeySize)
+	copy(publicKey, priv[32:])
+	return PublicKey(publicKey)
+}
+
+// Sign signs the given message with priv.
+// Ed25519 performs two passes over messages to be signed and therefore cannot
+// handle pre-hashed messages. Thus opts.HashFunc() must return zero to
+// indicate the message hasn't been hashed. This can be achieved by passing
+// crypto.Hash(0) as the value for opts.
+func (priv PrivateKey) Sign(rand io.Reader, message []byte, opts crypto.SignerOpts) (signature []byte, err error) {
+	if opts.HashFunc() != crypto.Hash(0) {
+		return nil, errors.New("ed25519: cannot sign hashed message")
+	}
+
+	return Sign(priv, message), nil
+}
+
+// GenerateKey generates a public/private key pair using entropy from rand.
+// If rand is nil, crypto/rand.Reader will be used.
+func GenerateKey(rand io.Reader) (publicKey PublicKey, privateKey PrivateKey, err error) {
+	if rand == nil {
+		rand = cryptorand.Reader
+	}
+
+	privateKey = make([]byte, PrivateKeySize)
+	publicKey = make([]byte, PublicKeySize)
+	_, err = io.ReadFull(rand, privateKey[:32])
+	if err != nil {
+		return nil, nil, err
+	}
+
+	digest := sha512.Sum512(privateKey[:32])
+	digest[0] &= 248
+	digest[31] &= 127
+	digest[31] |= 64
+
+	var A edwards25519.ExtendedGroupElement
+	var hBytes [32]byte
+	copy(hBytes[:], digest[:])
+	edwards25519.GeScalarMultBase(&A, &hBytes)
+	var publicKeyBytes [32]byte
+	A.ToBytes(&publicKeyBytes)
+
+	copy(privateKey[32:], publicKeyBytes[:])
+	copy(publicKey, publicKeyBytes[:])
+
+	return publicKey, privateKey, nil
+}
+
+// Sign signs the message with privateKey and returns a signature. It will
+// panic if len(privateKey) is not PrivateKeySize.
+func Sign(privateKey PrivateKey, message []byte) []byte {
+	if l := len(privateKey); l != PrivateKeySize {
+		panic("ed25519: bad private key length: " + strconv.Itoa(l))
+	}
+
+	h := sha512.New()
+	h.Write(privateKey[:32])
+
+	var digest1, messageDigest, hramDigest [64]byte
+	var expandedSecretKey [32]byte
+	h.Sum(digest1[:0])
+	copy(expandedSecretKey[:], digest1[:])
+	expandedSecretKey[0] &= 248
+	expandedSecretKey[31] &= 63
+	expandedSecretKey[31] |= 64
+
+	h.Reset()
+	h.Write(digest1[32:])
+	h.Write(message)
+	h.Sum(messageDigest[:0])
+
+	var messageDigestReduced [32]byte
+	edwards25519.ScReduce(&messageDigestReduced, &messageDigest)
+	var R edwards25519.ExtendedGroupElement
+	edwards25519.GeScalarMultBase(&R, &messageDigestReduced)
+
+	var encodedR [32]byte
+	R.ToBytes(&encodedR)
+
+	h.Reset()
+	h.Write(encodedR[:])
+	h.Write(privateKey[32:])
+	h.Write(message)
+	h.Sum(hramDigest[:0])
+	var hramDigestReduced [32]byte
+	edwards25519.ScReduce(&hramDigestReduced, &hramDigest)
+
+	var s [32]byte
+	edwards25519.ScMulAdd(&s, &hramDigestReduced, &expandedSecretKey, &messageDigestReduced)
+
+	signature := make([]byte, SignatureSize)
+	copy(signature[:], encodedR[:])
+	copy(signature[32:], s[:])
+
+	return signature
+}
+
+// Verify reports whether sig is a valid signature of message by publicKey. It
+// will panic if len(publicKey) is not PublicKeySize.
+func Verify(publicKey PublicKey, message, sig []byte) bool {
+	if l := len(publicKey); l != PublicKeySize {
+		panic("ed25519: bad public key length: " + strconv.Itoa(l))
+	}
+
+	if len(sig) != SignatureSize || sig[63]&224 != 0 {
+		return false
+	}
+
+	var A edwards25519.ExtendedGroupElement
+	var publicKeyBytes [32]byte
+	copy(publicKeyBytes[:], publicKey)
+	if !A.FromBytes(&publicKeyBytes) {
+		return false
+	}
+	edwards25519.FeNeg(&A.X, &A.X)
+	edwards25519.FeNeg(&A.T, &A.T)
+
+	h := sha512.New()
+	h.Write(sig[:32])
+	h.Write(publicKey[:])
+	h.Write(message)
+	var digest [64]byte
+	h.Sum(digest[:0])
+
+	var hReduced [32]byte
+	edwards25519.ScReduce(&hReduced, &digest)
+
+	var R edwards25519.ProjectiveGroupElement
+	var b [32]byte
+	copy(b[:], sig[32:])
+	edwards25519.GeDoubleScalarMultVartime(&R, &hReduced, &A, &b)
+
+	var checkR [32]byte
+	R.ToBytes(&checkR)
+	return subtle.ConstantTimeCompare(sig[:32], checkR[:]) == 1
+}

vendor/github.com/keybase/go-crypto/openpgp/armor/armor.go

@@ -4,14 +4,17 @@
 
 // Package armor implements OpenPGP ASCII Armor, see RFC 4880. OpenPGP Armor is
 // very similar to PEM except that it has an additional CRC checksum.
-package armor // import "golang.org/x/crypto/openpgp/armor"
+package armor // import "github.com/keybase/go-crypto/openpgp/armor"
 
 import (
 	"bufio"
 	"bytes"
 	"encoding/base64"
-	"golang.org/x/crypto/openpgp/errors"
 	"io"
+	"strings"
+	"unicode"
+
+	"github.com/keybase/go-crypto/openpgp/errors"
 )
 
 // A Block represents an OpenPGP armored structure.
@@ -65,7 +68,14 @@ type lineReader struct {
 	in  *bufio.Reader
 	buf []byte
 	eof bool
-	crc uint32
+	crc *uint32
+}
+
+// ourIsSpace checks if a rune is either space according to unicode
+// package, or ZeroWidthSpace (which is not a space according to
+// unicode module). Used to trim lines during header reading.
+func ourIsSpace(r rune) bool {
+	return r == '\u200b' || unicode.IsSpace(r)
 }
 
 func (l *lineReader) Read(p []byte) (n int, err error) {
@@ -79,13 +89,12 @@ func (l *lineReader) Read(p []byte) (n int, err error) {
 		return
 	}
 
-	line, isPrefix, err := l.in.ReadLine()
+	line, _, err := l.in.ReadLine()
 	if err != nil {
 		return
 	}
-	if isPrefix {
-		return 0, ArmorCorrupt
-	}
+
+	line = bytes.TrimFunc(line, ourIsSpace)
 
 	if len(line) == 5 && line[0] == '=' {
 		// This is the checksum line
@@ -95,13 +104,19 @@ func (l *lineReader) Read(p []byte) (n int, err error) {
 		if m != 3 || err != nil {
 			return
 		}
-		l.crc = uint32(expectedBytes[0])<<16 |
+		crc := uint32(expectedBytes[0])<<16 |
 			uint32(expectedBytes[1])<<8 |
 			uint32(expectedBytes[2])
+		l.crc = &crc
 
-		line, _, err = l.in.ReadLine()
-		if err != nil && err != io.EOF {
-			return
+		for {
+			line, _, err = l.in.ReadLine()
+			if err != nil && err != io.EOF {
+				return
+			}
+			if len(strings.TrimSpace(string(line))) > 0 {
+				break
+			}
 		}
 		if !bytes.HasPrefix(line, armorEnd) {
 			return 0, ArmorCorrupt
@@ -111,8 +126,11 @@ func (l *lineReader) Read(p []byte) (n int, err error) {
 		return 0, io.EOF
 	}
 
-	if len(line) > 96 {
-		return 0, ArmorCorrupt
+	if bytes.HasPrefix(line, armorEnd) {
+		// Unexpected ending, there was no checksum.
+		l.eof = true
+		l.crc = nil
+		return 0, io.EOF
 	}
 
 	n = copy(p, line)
@@ -142,7 +160,7 @@ func (r *openpgpReader) Read(p []byte) (n int, err error) {
 	r.currentCRC = crc24(r.currentCRC, p[:n])
 
 	if err == io.EOF {
-		if r.lReader.crc != uint32(r.currentCRC&crc24Mask) {
+		if r.lReader.crc != nil && *r.lReader.crc != uint32(r.currentCRC&crc24Mask) {
 			return 0, ArmorCorrupt
 		}
 	}
@@ -196,7 +214,7 @@ TryNextBlock:
 			p.Header[lastKey] += string(line)
 			continue
 		}
-		line = bytes.TrimSpace(line)
+		line = bytes.TrimFunc(line, ourIsSpace)
 		if len(line) == 0 {
 			break
 		}

vendor/github.com/keybase/go-crypto/openpgp/armor/encode.go

@@ -125,7 +125,7 @@ func (e *encoding) Close() (err error) {
 	var b64ChecksumBytes [4]byte
 	base64.StdEncoding.Encode(b64ChecksumBytes[:], checksumBytes[:])
 
-	return writeSlices(e.out, blockEnd, b64ChecksumBytes[:], newline, armorEnd, e.blockType, armorEndOfLine)
+	return writeSlices(e.out, blockEnd, b64ChecksumBytes[:], newline, armorEnd, e.blockType, armorEndOfLine, []byte{'\n'})
 }
 
 // Encode returns a WriteCloser which will encode the data written to it in

vendor/github.com/keybase/go-crypto/openpgp/ecdh/ecdh.go

@@ -0,0 +1,282 @@
+package ecdh
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/aes"
+	"crypto/elliptic"
+	"encoding/binary"
+	"errors"
+	"github.com/keybase/go-crypto/curve25519"
+	"io"
+	"math/big"
+)
+
+type PublicKey struct {
+	elliptic.Curve
+	X, Y *big.Int
+}
+
+type PrivateKey struct {
+	PublicKey
+	X *big.Int
+}
+
+// KDF implements Key Derivation Function as described in
+// https://tools.ietf.org/html/rfc6637#section-7
+func (e *PublicKey) KDF(S []byte, kdfParams []byte, hash crypto.Hash) []byte {
+	sLen := (e.Curve.Params().P.BitLen() + 7) / 8
+	buf := new(bytes.Buffer)
+	buf.Write([]byte{0, 0, 0, 1})
+	if sLen > len(S) {
+		// zero-pad the S. If we got invalid S (bigger than curve's
+		// P), we are going to produce invalid key. Garbage in,
+		// garbage out.
+		buf.Write(make([]byte, sLen-len(S)))
+	}
+	buf.Write(S)
+	buf.Write(kdfParams)
+
+	hashw := hash.New()
+
+	hashw.Write(buf.Bytes())
+	key := hashw.Sum(nil)
+
+	return key
+}
+
+// AESKeyUnwrap implements RFC 3394 Key Unwrapping. See
+// http://tools.ietf.org/html/rfc3394#section-2.2.1
+// Note: The second described algorithm ("index-based") is implemented
+// here.
+func AESKeyUnwrap(key, cipherText []byte) ([]byte, error) {
+	if len(cipherText)%8 != 0 {
+		return nil, errors.New("cipherText must by a multiple of 64 bits")
+	}
+
+	cipher, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	nblocks := len(cipherText)/8 - 1
+
+	// 1) Initialize variables.
+	// - Set A = C[0]
+	var A [aes.BlockSize]byte
+	copy(A[:8], cipherText[:8])
+
+	// For i = 1 to n
+	//   Set R[i] = C[i]
+	R := make([]byte, len(cipherText)-8)
+	copy(R, cipherText[8:])
+
+	// 2) Compute intermediate values.
+	for j := 5; j >= 0; j-- {
+		for i := nblocks - 1; i >= 0; i-- {
+			// B = AES-1(K, (A ^ t) | R[i]) where t = n*j+i
+			// A = MSB(64, B)
+			t := uint64(nblocks*j + i + 1)
+			At := binary.BigEndian.Uint64(A[:8]) ^ t
+			binary.BigEndian.PutUint64(A[:8], At)
+
+			copy(A[8:], R[i*8:i*8+8])
+			cipher.Decrypt(A[:], A[:])
+
+			// R[i] = LSB(B, 64)
+			copy(R[i*8:i*8+8], A[8:])
+		}
+	}
+
+	// 3) Output results.
+	// If A is an appropriate initial value (see 2.2.3),
+	for i := 0; i < 8; i++ {
+		if A[i] != 0xA6 {
+			return nil, errors.New("Failed to unwrap key (A is not IV)")
+		}
+	}
+
+	return R, nil
+}
+
+// AESKeyWrap implements RFC 3394 Key Wrapping. See
+// https://tools.ietf.org/html/rfc3394#section-2.2.2
+// Note: The second described algorithm ("index-based") is implemented
+// here.
+func AESKeyWrap(key, plainText []byte) ([]byte, error) {
+	if len(plainText)%8 != 0 {
+		return nil, errors.New("plainText must be a multiple of 64 bits")
+	}
+
+	cipher, err := aes.NewCipher(key) // NewCipher checks key size
+	if err != nil {
+		return nil, err
+	}
+
+	nblocks := len(plainText) / 8
+
+	// 1) Initialize variables.
+	var A [aes.BlockSize]byte
+	// Section 2.2.3.1 -- Initial Value
+	// http://tools.ietf.org/html/rfc3394#section-2.2.3.1
+	for i := 0; i < 8; i++ {
+		A[i] = 0xA6
+	}
+
+	// For i = 1 to n
+	//   Set R[i] = P[i]
+	R := make([]byte, len(plainText))
+	copy(R, plainText)
+
+	// 2) Calculate intermediate values.
+	for j := 0; j <= 5; j++ {
+		for i := 0; i < nblocks; i++ {
+			// B = AES(K, A | R[i])
+			copy(A[8:], R[i*8:i*8+8])
+			cipher.Encrypt(A[:], A[:])
+
+			// (Assume B = A)
+			// A = MSB(64, B) ^ t where t = (n*j)+1
+			t := uint64(j*nblocks + i + 1)
+			At := binary.BigEndian.Uint64(A[:8]) ^ t
+			binary.BigEndian.PutUint64(A[:8], At)
+
+			// R[i] = LSB(64, B)
+			copy(R[i*8:i*8+8], A[8:])
+		}
+	}
+
+	// 3) Output results.
+	// Set C[0] = A
+	// For i = 1 to n
+	//   C[i] = R[i]
+	return append(A[:8], R...), nil
+}
+
+// PadBuffer pads byte buffer buf to a length being multiple of
+// blockLen. Additional bytes appended to the buffer have value of the
+// number padded bytes. E.g. if the buffer is 3 bytes short of being
+// 40 bytes total, the appended bytes will be [03, 03, 03].
+func PadBuffer(buf []byte, blockLen int) []byte {
+	padding := blockLen - (len(buf) % blockLen)
+	if padding == 0 {
+		return buf
+	}
+
+	padBuf := make([]byte, padding)
+	for i := 0; i < padding; i++ {
+		padBuf[i] = byte(padding)
+	}
+
+	return append(buf, padBuf...)
+}
+
+// UnpadBuffer verifies that buffer contains proper padding and
+// returns buffer without the padding, or nil if the padding was
+// invalid.
+func UnpadBuffer(buf []byte, dataLen int) []byte {
+	padding := len(buf) - dataLen
+	outBuf := buf[:dataLen]
+
+	for i := dataLen; i < len(buf); i++ {
+		if buf[i] != byte(padding) {
+			// Invalid padding - bail out
+			return nil
+		}
+	}
+
+	return outBuf
+}
+
+func (e *PublicKey) Encrypt(random io.Reader, kdfParams []byte, plain []byte, hash crypto.Hash, kdfKeySize int) (Vx *big.Int, Vy *big.Int, C []byte, err error) {
+	// Vx, Vy - encryption key
+
+	// Note for Curve 25519 - curve25519 library already does key
+	// clamping in scalarMult, so we can use generic random scalar
+	// generation from elliptic.
+	priv, Vx, Vy, err := elliptic.GenerateKey(e.Curve, random)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+
+	// Sx, Sy - shared secret
+	Sx, _ := e.Curve.ScalarMult(e.X, e.Y, priv)
+
+	// Encrypt the payload with KDF-ed S as the encryption key. Pass
+	// the ciphertext along with V to the recipient. Recipient can
+	// generate S using V and their priv key, and then KDF(S), on
+	// their own, to get encryption key and decrypt the ciphertext,
+	// revealing encryption key for symmetric encryption later.
+
+	plain = PadBuffer(plain, 8)
+	key := e.KDF(Sx.Bytes(), kdfParams, hash)
+
+	// Take only as many bytes from key as the key length (the hash
+	// result might be bigger)
+	encrypted, err := AESKeyWrap(key[:kdfKeySize], plain)
+
+	return Vx, Vy, encrypted, nil
+}
+
+func (e *PrivateKey) DecryptShared(X, Y *big.Int) []byte {
+	Sx, _ := e.Curve.ScalarMult(X, Y, e.X.Bytes())
+	return Sx.Bytes()
+}
+
+func countBits(buffer []byte) int {
+	var headerLen int
+	switch buffer[0] {
+	case 0x4:
+		headerLen = 3
+	case 0x40:
+		headerLen = 7
+	default:
+		// Unexpected header - but we can still count the bits.
+		val := buffer[0]
+		headerLen = 0
+		for val > 0 {
+			val = val / 2
+			headerLen++
+		}
+	}
+
+	return headerLen + (len(buffer)-1)*8
+}
+
+// elliptic.Marshal and elliptic.Unmarshal only marshals uncompressed
+// 0x4 MPI types. These functions will check if the curve is cv25519,
+// and if so, use 0x40 compressed type to (un)marshal. Otherwise,
+// elliptic.(Un)marshal will be called.
+
+// Marshal encodes point into either 0x4 uncompressed point form, or
+// 0x40 compressed point for Curve 25519.
+func Marshal(curve elliptic.Curve, x, y *big.Int) (buf []byte, bitSize int) {
+	// NOTE: Read more about MPI encoding in the RFC:
+	// https://tools.ietf.org/html/rfc4880#section-3.2
+
+	// We are required to encode size in bits, counting from the most-
+	// significant non-zero bit. So assuming that the buffer never
+	// starts with 0x00, we only need to count bits in the first byte
+	// - and in current implentation it will always be 0x4 or 0x40.
+
+	cv, ok := curve25519.ToCurve25519(curve)
+	if ok {
+		buf = cv.MarshalType40(x, y)
+	} else {
+		buf = elliptic.Marshal(curve, x, y)
+	}
+
+	return buf, countBits(buf)
+}
+
+// Unmarshal converts point, serialized by Marshal, into x, y pair.
+// For 0x40 compressed points (for Curve 25519), y will always be 0.
+// It is an error if point is not on the curve, On error, x = nil.
+func Unmarshal(curve elliptic.Curve, data []byte) (x, y *big.Int) {
+	cv, ok := curve25519.ToCurve25519(curve)
+	if ok {
+		return cv.UnmarshalType40(data)
+	}
+
+	return elliptic.Unmarshal(curve, data)
+}

vendor/github.com/keybase/go-crypto/openpgp/elgamal/elgamal.go

@@ -10,7 +10,7 @@
 // This form of ElGamal embeds PKCS#1 v1.5 padding, which may make it
 // unsuitable for other protocols. RSA should be used in preference in any
 // case.
-package elgamal // import "golang.org/x/crypto/openpgp/elgamal"
+package elgamal // import "github.com/keybase/go-crypto/openpgp/elgamal"
 
 import (
 	"crypto/rand"

vendor/github.com/keybase/go-crypto/openpgp/errors/errors.go

@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // Package errors contains common error types for the OpenPGP packages.
-package errors // import "golang.org/x/crypto/openpgp/errors"
+package errors // import "github.com/keybase/go-crypto/openpgp/errors"
 
 import (
 	"strconv"

vendor/github.com/keybase/go-crypto/openpgp/keys.go

@@ -0,0 +1,902 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package openpgp
+
+import (
+	"crypto/hmac"
+	"encoding/binary"
+	"io"
+	"time"
+
+	"github.com/keybase/go-crypto/openpgp/armor"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/packet"
+	"github.com/keybase/go-crypto/rsa"
+)
+
+// PublicKeyType is the armor type for a PGP public key.
+var PublicKeyType = "PGP PUBLIC KEY BLOCK"
+
+// PrivateKeyType is the armor type for a PGP private key.
+var PrivateKeyType = "PGP PRIVATE KEY BLOCK"
+
+// An Entity represents the components of an OpenPGP key: a primary public key
+// (which must be a signing key), one or more identities claimed by that key,
+// and zero or more subkeys, which may be encryption keys.
+type Entity struct {
+	PrimaryKey  *packet.PublicKey
+	PrivateKey  *packet.PrivateKey
+	Identities  map[string]*Identity // indexed by Identity.Name
+	Revocations []*packet.Signature
+	// Revocations that are signed by designated revokers. Reading keys
+	// will not verify these revocations, because it won't have access to
+	// issuers' public keys, API consumers should do this instead (or
+	// not, and just assume that the key is probably revoked).
+	UnverifiedRevocations []*packet.Signature
+	Subkeys               []Subkey
+	BadSubkeys            []BadSubkey
+}
+
+// An Identity represents an identity claimed by an Entity and zero or more
+// assertions by other entities about that claim.
+type Identity struct {
+	Name          string // by convention, has the form "Full Name (comment) <email@example.com>"
+	UserId        *packet.UserId
+	SelfSignature *packet.Signature
+	Signatures    []*packet.Signature
+	Revocation    *packet.Signature
+}
+
+// A Subkey is an additional public key in an Entity. Subkeys can be used for
+// encryption.
+type Subkey struct {
+	PublicKey  *packet.PublicKey
+	PrivateKey *packet.PrivateKey
+	Sig        *packet.Signature
+	Revocation *packet.Signature
+}
+
+// BadSubkey is one that failed reconstruction, but we'll keep it around for
+// informational purposes.
+type BadSubkey struct {
+	Subkey
+	Err error
+}
+
+// A Key identifies a specific public key in an Entity. This is either the
+// Entity's primary key or a subkey.
+type Key struct {
+	Entity        *Entity
+	PublicKey     *packet.PublicKey
+	PrivateKey    *packet.PrivateKey
+	SelfSignature *packet.Signature
+	KeyFlags      packet.KeyFlagBits
+}
+
+// A KeyRing provides access to public and private keys.
+type KeyRing interface {
+
+	// KeysById returns the set of keys that have the given key id.
+	// fp can be optionally supplied, which is the full key fingerprint.
+	// If it's provided, then it must match. This comes up in the case
+	// of GPG subpacket 33.
+	KeysById(id uint64, fp []byte) []Key
+
+	// KeysByIdAndUsage returns the set of keys with the given id
+	// that also meet the key usage given by requiredUsage.
+	// The requiredUsage is expressed as the bitwise-OR of
+	// packet.KeyFlag* values.
+	// fp can be optionally supplied, which is the full key fingerprint.
+	// If it's provided, then it must match. This comes up in the case
+	// of GPG subpacket 33.
+	KeysByIdUsage(id uint64, fp []byte, requiredUsage byte) []Key
+
+	// DecryptionKeys returns all private keys that are valid for
+	// decryption.
+	DecryptionKeys() []Key
+}
+
+// primaryIdentity returns the Identity marked as primary or the first identity
+// if none are so marked.
+func (e *Entity) primaryIdentity() *Identity {
+	var firstIdentity *Identity
+	for _, ident := range e.Identities {
+		if firstIdentity == nil {
+			firstIdentity = ident
+		}
+		if ident.SelfSignature.IsPrimaryId != nil && *ident.SelfSignature.IsPrimaryId {
+			return ident
+		}
+	}
+	return firstIdentity
+}
+
+// encryptionKey returns the best candidate Key for encrypting a message to the
+// given Entity.
+func (e *Entity) encryptionKey(now time.Time) (Key, bool) {
+	candidateSubkey := -1
+
+	// Iterate the keys to find the newest key
+	var maxTime time.Time
+	for i, subkey := range e.Subkeys {
+
+		// NOTE(maxtaco)
+		// If there is a Flags subpacket, then we have to follow it, and only
+		// use keys that are marked for Encryption of Communication.  If there
+		// isn't a Flags subpacket, and this is an Encrypt-Only key (right now only ElGamal
+		// suffices), then we implicitly use it. The check for primary below is a little
+		// more open-ended, but for now, let's be strict and potentially open up
+		// if we see bugs in the wild.
+		//
+		// One more note: old DSA/ElGamal keys tend not to have the Flags subpacket,
+		// so this sort of thing is pretty important for encrypting to older keys.
+		//
+		if ((subkey.Sig.FlagsValid && subkey.Sig.FlagEncryptCommunications) ||
+			(!subkey.Sig.FlagsValid && subkey.PublicKey.PubKeyAlgo == packet.PubKeyAlgoElGamal)) &&
+			subkey.PublicKey.PubKeyAlgo.CanEncrypt() &&
+			!subkey.Sig.KeyExpired(now) &&
+			subkey.Revocation == nil &&
+			(maxTime.IsZero() || subkey.Sig.CreationTime.After(maxTime)) {
+			candidateSubkey = i
+			maxTime = subkey.Sig.CreationTime
+		}
+	}
+
+	if candidateSubkey != -1 {
+		subkey := e.Subkeys[candidateSubkey]
+		return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig, subkey.Sig.GetKeyFlags()}, true
+	}
+
+	// If we don't have any candidate subkeys for encryption and
+	// the primary key doesn't have any usage metadata then we
+	// assume that the primary key is ok. Or, if the primary key is
+	// marked as ok to encrypt to, then we can obviously use it.
+	//
+	// NOTE(maxtaco) - see note above, how this policy is a little too open-ended
+	// for my liking, but leave it for now.
+	i := e.primaryIdentity()
+	if (!i.SelfSignature.FlagsValid || i.SelfSignature.FlagEncryptCommunications) &&
+		e.PrimaryKey.PubKeyAlgo.CanEncrypt() &&
+		!i.SelfSignature.KeyExpired(now) {
+		return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature, i.SelfSignature.GetKeyFlags()}, true
+	}
+
+	// This Entity appears to be signing only.
+	return Key{}, false
+}
+
+// signingKey return the best candidate Key for signing a message with this
+// Entity.
+func (e *Entity) signingKey(now time.Time) (Key, bool) {
+	candidateSubkey := -1
+
+	for i, subkey := range e.Subkeys {
+		if (!subkey.Sig.FlagsValid || subkey.Sig.FlagSign) &&
+			subkey.PrivateKey.PrivateKey != nil &&
+			subkey.PublicKey.PubKeyAlgo.CanSign() &&
+			subkey.Revocation == nil &&
+			!subkey.Sig.KeyExpired(now) {
+			candidateSubkey = i
+			break
+		}
+	}
+
+	if candidateSubkey != -1 {
+		subkey := e.Subkeys[candidateSubkey]
+		return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig, subkey.Sig.GetKeyFlags()}, true
+	}
+
+	// If we have no candidate subkey then we assume that it's ok to sign
+	// with the primary key.
+	i := e.primaryIdentity()
+	if (!i.SelfSignature.FlagsValid || i.SelfSignature.FlagSign) &&
+		e.PrimaryKey.PubKeyAlgo.CanSign() &&
+		!i.SelfSignature.KeyExpired(now) &&
+		e.PrivateKey.PrivateKey != nil {
+		return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature, i.SelfSignature.GetKeyFlags()}, true
+	}
+
+	return Key{}, false
+}
+
+// An EntityList contains one or more Entities.
+type EntityList []*Entity
+
+func keyMatchesIdAndFingerprint(key *packet.PublicKey, id uint64, fp []byte) bool {
+	if key.KeyId != id {
+		return false
+	}
+	if fp == nil {
+		return true
+	}
+	return hmac.Equal(fp, key.Fingerprint[:])
+}
+
+// KeysById returns the set of keys that have the given key id.
+// fp can be optionally supplied, which is the full key fingerprint.
+// If it's provided, then it must match. This comes up in the case
+// of GPG subpacket 33.
+func (el EntityList) KeysById(id uint64, fp []byte) (keys []Key) {
+	for _, e := range el {
+		if keyMatchesIdAndFingerprint(e.PrimaryKey, id, fp) {
+			var selfSig *packet.Signature
+			for _, ident := range e.Identities {
+				if selfSig == nil {
+					selfSig = ident.SelfSignature
+				} else if ident.SelfSignature.IsPrimaryId != nil && *ident.SelfSignature.IsPrimaryId {
+					selfSig = ident.SelfSignature
+					break
+				}
+			}
+
+			var keyFlags packet.KeyFlagBits
+			for _, ident := range e.Identities {
+				keyFlags.Merge(ident.SelfSignature.GetKeyFlags())
+			}
+
+			keys = append(keys, Key{e, e.PrimaryKey, e.PrivateKey, selfSig, keyFlags})
+		}
+
+		for _, subKey := range e.Subkeys {
+			if keyMatchesIdAndFingerprint(subKey.PublicKey, id, fp) {
+
+				// If there's both a a revocation and a sig, then take the
+				// revocation. Otherwise, we can proceed with the sig.
+				sig := subKey.Revocation
+				if sig == nil {
+					sig = subKey.Sig
+				}
+
+				keys = append(keys, Key{e, subKey.PublicKey, subKey.PrivateKey, sig, sig.GetKeyFlags()})
+			}
+		}
+	}
+	return
+}
+
+// KeysByIdAndUsage returns the set of keys with the given id that also meet
+// the key usage given by requiredUsage.  The requiredUsage is expressed as
+// the bitwise-OR of packet.KeyFlag* values.
+// fp can be optionally supplied, which is the full key fingerprint.
+// If it's provided, then it must match. This comes up in the case
+// of GPG subpacket 33.
+func (el EntityList) KeysByIdUsage(id uint64, fp []byte, requiredUsage byte) (keys []Key) {
+	for _, key := range el.KeysById(id, fp) {
+		if len(key.Entity.Revocations) > 0 {
+			continue
+		}
+
+		if key.SelfSignature.RevocationReason != nil {
+			continue
+		}
+
+		if requiredUsage != 0 {
+			var usage byte
+
+			switch {
+			case key.KeyFlags.Valid:
+				usage = key.KeyFlags.BitField
+
+			case key.PublicKey.PubKeyAlgo == packet.PubKeyAlgoElGamal:
+				// We also need to handle the case where, although the sig's
+				// flags aren't valid, the key can is implicitly usable for
+				// encryption by virtue of being ElGamal. See also the comment
+				// in encryptionKey() above.
+				usage |= packet.KeyFlagEncryptCommunications
+				usage |= packet.KeyFlagEncryptStorage
+
+			case key.PublicKey.PubKeyAlgo == packet.PubKeyAlgoDSA ||
+				key.PublicKey.PubKeyAlgo == packet.PubKeyAlgoECDSA ||
+				key.PublicKey.PubKeyAlgo == packet.PubKeyAlgoEdDSA:
+				usage |= packet.KeyFlagSign
+
+			// For a primary RSA key without any key flags, be as permissiable
+			// as possible.
+			case key.PublicKey.PubKeyAlgo == packet.PubKeyAlgoRSA &&
+				keyMatchesIdAndFingerprint(key.Entity.PrimaryKey, id, fp):
+				usage = (packet.KeyFlagCertify | packet.KeyFlagSign |
+					packet.KeyFlagEncryptCommunications | packet.KeyFlagEncryptStorage)
+			}
+
+			if usage&requiredUsage != requiredUsage {
+				continue
+			}
+		}
+
+		keys = append(keys, key)
+	}
+	return
+}
+
+// DecryptionKeys returns all private keys that are valid for decryption.
+func (el EntityList) DecryptionKeys() (keys []Key) {
+	for _, e := range el {
+		for _, subKey := range e.Subkeys {
+			if subKey.PrivateKey != nil && subKey.PrivateKey.PrivateKey != nil && (!subKey.Sig.FlagsValid || subKey.Sig.FlagEncryptStorage || subKey.Sig.FlagEncryptCommunications) {
+				keys = append(keys, Key{e, subKey.PublicKey, subKey.PrivateKey, subKey.Sig, subKey.Sig.GetKeyFlags()})
+			}
+		}
+	}
+	return
+}
+
+// ReadArmoredKeyRing reads one or more public/private keys from an armor keyring file.
+func ReadArmoredKeyRing(r io.Reader) (EntityList, error) {
+	block, err := armor.Decode(r)
+	if err == io.EOF {
+		return nil, errors.InvalidArgumentError("no armored data found")
+	}
+	if err != nil {
+		return nil, err
+	}
+	if block.Type != PublicKeyType && block.Type != PrivateKeyType {
+		return nil, errors.InvalidArgumentError("expected public or private key block, got: " + block.Type)
+	}
+
+	return ReadKeyRing(block.Body)
+}
+
+// ReadKeyRing reads one or more public/private keys. Unsupported keys are
+// ignored as long as at least a single valid key is found.
+func ReadKeyRing(r io.Reader) (el EntityList, err error) {
+	packets := packet.NewReader(r)
+	var lastUnsupportedError error
+
+	for {
+		var e *Entity
+		e, err = ReadEntity(packets)
+		if err != nil {
+			// TODO: warn about skipped unsupported/unreadable keys
+			if _, ok := err.(errors.UnsupportedError); ok {
+				lastUnsupportedError = err
+				err = readToNextPublicKey(packets)
+			} else if _, ok := err.(errors.StructuralError); ok {
+				// Skip unreadable, badly-formatted keys
+				lastUnsupportedError = err
+				err = readToNextPublicKey(packets)
+			}
+			if err == io.EOF {
+				err = nil
+				break
+			}
+			if err != nil {
+				el = nil
+				break
+			}
+		} else {
+			el = append(el, e)
+		}
+	}
+
+	if len(el) == 0 && err == nil {
+		err = lastUnsupportedError
+	}
+	return
+}
+
+// readToNextPublicKey reads packets until the start of the entity and leaves
+// the first packet of the new entity in the Reader.
+func readToNextPublicKey(packets *packet.Reader) (err error) {
+	var p packet.Packet
+	for {
+		p, err = packets.Next()
+		if err == io.EOF {
+			return
+		} else if err != nil {
+			if _, ok := err.(errors.UnsupportedError); ok {
+				err = nil
+				continue
+			}
+			return
+		}
+
+		if pk, ok := p.(*packet.PublicKey); ok && !pk.IsSubkey {
+			packets.Unread(p)
+			return
+		}
+	}
+
+	panic("unreachable")
+}
+
+// ReadEntity reads an entity (public key, identities, subkeys etc) from the
+// given Reader.
+func ReadEntity(packets *packet.Reader) (*Entity, error) {
+	e := new(Entity)
+	e.Identities = make(map[string]*Identity)
+
+	p, err := packets.Next()
+	if err != nil {
+		return nil, err
+	}
+
+	var ok bool
+	if e.PrimaryKey, ok = p.(*packet.PublicKey); !ok {
+		if e.PrivateKey, ok = p.(*packet.PrivateKey); !ok {
+			packets.Unread(p)
+			return nil, errors.StructuralError("first packet was not a public/private key")
+		} else {
+			e.PrimaryKey = &e.PrivateKey.PublicKey
+		}
+	}
+
+	if !e.PrimaryKey.PubKeyAlgo.CanSign() {
+		return nil, errors.StructuralError("primary key cannot be used for signatures")
+	}
+
+	var current *Identity
+	var revocations []*packet.Signature
+
+	designatedRevokers := make(map[uint64]bool)
+EachPacket:
+	for {
+		p, err := packets.Next()
+		if err == io.EOF {
+			break
+		} else if err != nil {
+			return nil, err
+		}
+		switch pkt := p.(type) {
+		case *packet.UserId:
+
+			// Make a new Identity object, that we might wind up throwing away.
+			// We'll only add it if we get a valid self-signature over this
+			// userID.
+			current = new(Identity)
+			current.Name = pkt.Id
+			current.UserId = pkt
+		case *packet.Signature:
+			if pkt.SigType == packet.SigTypeKeyRevocation {
+				// These revocations won't revoke UIDs (see
+				// SigTypeIdentityRevocation). Handle these first,
+				// because key might have revocation coming from
+				// another key (designated revoke).
+				revocations = append(revocations, pkt)
+				continue
+			}
+
+			// These are signatures by other people on this key. Let's just ignore them
+			// from the beginning, since they shouldn't affect our key decoding one way
+			// or the other.
+			if pkt.IssuerKeyId != nil && *pkt.IssuerKeyId != e.PrimaryKey.KeyId {
+				continue
+			}
+
+			// If this is a signature made by the keyholder, and the signature has stubbed out
+			// critical packets, then *now* we need to bail out.
+			if e := pkt.StubbedOutCriticalError; e != nil {
+				return nil, e
+			}
+
+			// Next handle the case of a self-signature. According to RFC8440,
+			// Section 5.2.3.3, if there are several self-signatures,
+			// we should take the newer one.  If they were both created
+			// at the same time, but one of them has keyflags specified and the
+			// other doesn't, keep the one with the keyflags. We have actually
+			// seen this in the wild (see the 'Yield' test in read_test.go).
+			// If there is a tie, and both have the same value for FlagsValid,
+			// then "last writer wins."
+			//
+			// HOWEVER! We have seen yet more keys in the wild (see the 'Spiros'
+			// test in read_test.go), in which the later self-signature is a bunch
+			// of junk, and doesn't even specify key flags. Does it really make
+			// sense to overwrite reasonable key flags with the empty set? I'm not
+			// sure what that would be trying to achieve, and plus GPG seems to be
+			// ok with this situation, and ignores the later (empty) keyflag set.
+			// So further tighten our overwrite rules, and only allow the later
+			// signature to overwrite the earlier signature if so doing won't
+			// trash the key flags.
+			if current != nil &&
+				(current.SelfSignature == nil ||
+					(!pkt.CreationTime.Before(current.SelfSignature.CreationTime) &&
+						(pkt.FlagsValid || !current.SelfSignature.FlagsValid))) &&
+				(pkt.SigType == packet.SigTypePositiveCert || pkt.SigType == packet.SigTypeGenericCert) &&
+				pkt.IssuerKeyId != nil &&
+				*pkt.IssuerKeyId == e.PrimaryKey.KeyId {
+
+				if err = e.PrimaryKey.VerifyUserIdSignature(current.Name, e.PrimaryKey, pkt); err == nil {
+
+					current.SelfSignature = pkt
+
+					// NOTE(maxtaco) 2016.01.11
+					// Only register an identity once we've gotten a valid self-signature.
+					// It's possible therefore for us to throw away `current` in the case
+					// no valid self-signatures were found. That's OK as long as there are
+					// other identies that make sense.
+					//
+					// NOTE! We might later see a revocation for this very same UID, and it
+					// won't be undone. We've preserved this feature from the original
+					// Google OpenPGP we forked from.
+					e.Identities[current.Name] = current
+				} else {
+					// We really should warn that there was a failure here. Not raise an error
+					// since this really shouldn't be a fail-stop error.
+				}
+			} else if current != nil && pkt.SigType == packet.SigTypeIdentityRevocation {
+				if err = e.PrimaryKey.VerifyUserIdSignature(current.Name, e.PrimaryKey, pkt); err == nil {
+					// Note: we are not removing the identity from
+					// e.Identities. Caller can always filter by Revocation
+					// field to ignore revoked identities.
+					current.Revocation = pkt
+				}
+			} else if pkt.SigType == packet.SigTypeDirectSignature {
+				if err = e.PrimaryKey.VerifyRevocationSignature(e.PrimaryKey, pkt); err == nil {
+					if desig := pkt.DesignatedRevoker; desig != nil {
+						// If it's a designated revoker signature, take last 8 octects
+						// of fingerprint as Key ID and save it to designatedRevokers
+						// map. We consult this map later to see if a foreign
+						// revocation should be added to UnverifiedRevocations.
+						keyID := binary.BigEndian.Uint64(desig.Fingerprint[len(desig.Fingerprint)-8:])
+						designatedRevokers[keyID] = true
+					}
+				}
+			} else if current == nil {
+				// NOTE(maxtaco)
+				//
+				// See https://github.com/keybase/client/issues/2666
+				//
+				// There might have been a user attribute picture before this signature,
+				// in which case this is still a valid PGP key. In the future we might
+				// not ignore user attributes (like picture). But either way, it doesn't
+				// make sense to bail out here. Keep looking for other valid signatures.
+				//
+				// Used to be:
+				//    return nil, errors.StructuralError("signature packet found before user id packet")
+			} else {
+				current.Signatures = append(current.Signatures, pkt)
+			}
+		case *packet.PrivateKey:
+			if pkt.IsSubkey == false {
+				packets.Unread(p)
+				break EachPacket
+			}
+			err = addSubkey(e, packets, &pkt.PublicKey, pkt)
+			if err != nil {
+				return nil, err
+			}
+		case *packet.PublicKey:
+			if pkt.IsSubkey == false {
+				packets.Unread(p)
+				break EachPacket
+			}
+			err = addSubkey(e, packets, pkt, nil)
+			if err != nil {
+				return nil, err
+			}
+		default:
+			// we ignore unknown packets
+		}
+	}
+
+	if len(e.Identities) == 0 {
+		return nil, errors.StructuralError("entity without any identities")
+	}
+
+	for _, revocation := range revocations {
+		if revocation.IssuerKeyId == nil || *revocation.IssuerKeyId == e.PrimaryKey.KeyId {
+			// Key revokes itself, something that we can verify.
+			err = e.PrimaryKey.VerifyRevocationSignature(e.PrimaryKey, revocation)
+			if err == nil {
+				e.Revocations = append(e.Revocations, revocation)
+			} else {
+				return nil, errors.StructuralError("revocation signature signed by alternate key")
+			}
+		} else if revocation.IssuerKeyId != nil {
+			if _, ok := designatedRevokers[*revocation.IssuerKeyId]; ok {
+				// Revocation is done by certified designated revoker,
+				// but we can't verify the revocation.
+				e.UnverifiedRevocations = append(e.UnverifiedRevocations, revocation)
+			}
+		}
+	}
+
+	return e, nil
+}
+
+func addSubkey(e *Entity, packets *packet.Reader, pub *packet.PublicKey, priv *packet.PrivateKey) error {
+	var subKey Subkey
+	subKey.PublicKey = pub
+	subKey.PrivateKey = priv
+	var lastErr error
+	for {
+		p, err := packets.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return errors.StructuralError("subkey signature invalid: " + err.Error())
+		}
+		sig, ok := p.(*packet.Signature)
+		if !ok {
+			// Hit a non-signature packet, so assume we're up to the next key
+			packets.Unread(p)
+			break
+		}
+		if st := sig.SigType; st != packet.SigTypeSubkeyBinding && st != packet.SigTypeSubkeyRevocation {
+
+			// Note(maxtaco):
+			// We used to error out here, but instead, let's fast-forward past
+			// packets that are in the wrong place (like misplaced 0x13 signatures)
+			// until we get to one that works.  For a test case,
+			// see TestWithBadSubkeySignaturePackets.
+
+			continue
+		}
+		err = e.PrimaryKey.VerifyKeySignature(subKey.PublicKey, sig)
+		if err != nil {
+			// Non valid signature, so again, no need to abandon all hope, just continue;
+			// make a note of the error we hit.
+			lastErr = errors.StructuralError("subkey signature invalid: " + err.Error())
+			continue
+		}
+		switch sig.SigType {
+		case packet.SigTypeSubkeyBinding:
+			// Does the "new" sig set expiration to later date than
+			// "previous" sig?
+			if subKey.Sig == nil || subKey.Sig.ExpiresBeforeOther(sig) {
+				subKey.Sig = sig
+			}
+		case packet.SigTypeSubkeyRevocation:
+			// First writer wins
+			if subKey.Revocation == nil {
+				subKey.Revocation = sig
+			}
+		}
+	}
+	if subKey.Sig != nil {
+		e.Subkeys = append(e.Subkeys, subKey)
+	} else {
+		if lastErr == nil {
+			lastErr = errors.StructuralError("Subkey wasn't signed; expected a 'binding' signature")
+		}
+		e.BadSubkeys = append(e.BadSubkeys, BadSubkey{Subkey: subKey, Err: lastErr})
+	}
+	return nil
+}
+
+const defaultRSAKeyBits = 2048
+
+// NewEntity returns an Entity that contains a fresh RSA/RSA keypair with a
+// single identity composed of the given full name, comment and email, any of
+// which may be empty but must not contain any of "()<>\x00".
+// If config is nil, sensible defaults will be used.
+func NewEntity(name, comment, email string, config *packet.Config) (*Entity, error) {
+	currentTime := config.Now()
+
+	bits := defaultRSAKeyBits
+	if config != nil && config.RSABits != 0 {
+		bits = config.RSABits
+	}
+
+	uid := packet.NewUserId(name, comment, email)
+	if uid == nil {
+		return nil, errors.InvalidArgumentError("user id field contained invalid characters")
+	}
+	signingPriv, err := rsa.GenerateKey(config.Random(), bits)
+	if err != nil {
+		return nil, err
+	}
+	encryptingPriv, err := rsa.GenerateKey(config.Random(), bits)
+	if err != nil {
+		return nil, err
+	}
+
+	e := &Entity{
+		PrimaryKey: packet.NewRSAPublicKey(currentTime, &signingPriv.PublicKey),
+		PrivateKey: packet.NewRSAPrivateKey(currentTime, signingPriv),
+		Identities: make(map[string]*Identity),
+	}
+	isPrimaryId := true
+	e.Identities[uid.Id] = &Identity{
+		Name:   uid.Name,
+		UserId: uid,
+		SelfSignature: &packet.Signature{
+			CreationTime: currentTime,
+			SigType:      packet.SigTypePositiveCert,
+			PubKeyAlgo:   packet.PubKeyAlgoRSA,
+			Hash:         config.Hash(),
+			IsPrimaryId:  &isPrimaryId,
+			FlagsValid:   true,
+			FlagSign:     true,
+			FlagCertify:  true,
+			IssuerKeyId:  &e.PrimaryKey.KeyId,
+		},
+	}
+
+	e.Subkeys = make([]Subkey, 1)
+	e.Subkeys[0] = Subkey{
+		PublicKey:  packet.NewRSAPublicKey(currentTime, &encryptingPriv.PublicKey),
+		PrivateKey: packet.NewRSAPrivateKey(currentTime, encryptingPriv),
+		Sig: &packet.Signature{
+			CreationTime:              currentTime,
+			SigType:                   packet.SigTypeSubkeyBinding,
+			PubKeyAlgo:                packet.PubKeyAlgoRSA,
+			Hash:                      config.Hash(),
+			FlagsValid:                true,
+			FlagEncryptStorage:        true,
+			FlagEncryptCommunications: true,
+			IssuerKeyId:               &e.PrimaryKey.KeyId,
+		},
+	}
+	e.Subkeys[0].PublicKey.IsSubkey = true
+	e.Subkeys[0].PrivateKey.IsSubkey = true
+
+	return e, nil
+}
+
+// SerializePrivate serializes an Entity, including private key material, to
+// the given Writer. For now, it must only be used on an Entity returned from
+// NewEntity.
+// If config is nil, sensible defaults will be used.
+func (e *Entity) SerializePrivate(w io.Writer, config *packet.Config) (err error) {
+	err = e.PrivateKey.Serialize(w)
+	if err != nil {
+		return
+	}
+	for _, ident := range e.Identities {
+		err = ident.UserId.Serialize(w)
+		if err != nil {
+			return
+		}
+		if e.PrivateKey.PrivateKey != nil {
+			err = ident.SelfSignature.SignUserId(ident.UserId.Id, e.PrimaryKey, e.PrivateKey, config)
+			if err != nil {
+				return
+			}
+		}
+		err = ident.SelfSignature.Serialize(w)
+		if err != nil {
+			return
+		}
+	}
+	for _, subkey := range e.Subkeys {
+		err = subkey.PrivateKey.Serialize(w)
+		if err != nil {
+			return
+		}
+		// Workaround shortcoming of SignKey(), which doesn't work to reverse-sign
+		// sub-signing keys. So if requested, just reuse the signatures already
+		// available to us (if we read this key from a keyring).
+		if e.PrivateKey.PrivateKey != nil && !config.ReuseSignatures() {
+			err = subkey.Sig.SignKey(subkey.PublicKey, e.PrivateKey, config)
+			if err != nil {
+				return
+			}
+		}
+
+		if subkey.Revocation != nil {
+			err = subkey.Revocation.Serialize(w)
+			if err != nil {
+				return
+			}
+		}
+
+		err = subkey.Sig.Serialize(w)
+		if err != nil {
+			return
+		}
+	}
+	return nil
+}
+
+// Serialize writes the public part of the given Entity to w. (No private
+// key material will be output).
+func (e *Entity) Serialize(w io.Writer) error {
+	err := e.PrimaryKey.Serialize(w)
+	if err != nil {
+		return err
+	}
+	for _, ident := range e.Identities {
+		err = ident.UserId.Serialize(w)
+		if err != nil {
+			return err
+		}
+		err = ident.SelfSignature.Serialize(w)
+		if err != nil {
+			return err
+		}
+		for _, sig := range ident.Signatures {
+			err = sig.Serialize(w)
+			if err != nil {
+				return err
+			}
+		}
+	}
+	for _, subkey := range e.Subkeys {
+		err = subkey.PublicKey.Serialize(w)
+		if err != nil {
+			return err
+		}
+
+		if subkey.Revocation != nil {
+			err = subkey.Revocation.Serialize(w)
+			if err != nil {
+				return err
+			}
+		}
+		err = subkey.Sig.Serialize(w)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// SignIdentity adds a signature to e, from signer, attesting that identity is
+// associated with e. The provided identity must already be an element of
+// e.Identities and the private key of signer must have been decrypted if
+// necessary.
+// If config is nil, sensible defaults will be used.
+func (e *Entity) SignIdentity(identity string, signer *Entity, config *packet.Config) error {
+	if signer.PrivateKey == nil {
+		return errors.InvalidArgumentError("signing Entity must have a private key")
+	}
+	if signer.PrivateKey.Encrypted {
+		return errors.InvalidArgumentError("signing Entity's private key must be decrypted")
+	}
+	ident, ok := e.Identities[identity]
+	if !ok {
+		return errors.InvalidArgumentError("given identity string not found in Entity")
+	}
+
+	sig := &packet.Signature{
+		SigType:      packet.SigTypeGenericCert,
+		PubKeyAlgo:   signer.PrivateKey.PubKeyAlgo,
+		Hash:         config.Hash(),
+		CreationTime: config.Now(),
+		IssuerKeyId:  &signer.PrivateKey.KeyId,
+	}
+	if err := sig.SignUserId(identity, e.PrimaryKey, signer.PrivateKey, config); err != nil {
+		return err
+	}
+	ident.Signatures = append(ident.Signatures, sig)
+	return nil
+}
+
+// CopySubkeyRevocations copies subkey revocations from the src Entity over
+// to the receiver entity. We need this because `gpg --export-secret-key` does
+// not appear to output subkey revocations.  In this case we need to manually
+// merge with the output of `gpg --export`.
+func (e *Entity) CopySubkeyRevocations(src *Entity) {
+	m := make(map[[20]byte]*packet.Signature)
+	for _, subkey := range src.Subkeys {
+		if subkey.Revocation != nil {
+			m[subkey.PublicKey.Fingerprint] = subkey.Revocation
+		}
+	}
+	for i, subkey := range e.Subkeys {
+		if r := m[subkey.PublicKey.Fingerprint]; r != nil {
+			e.Subkeys[i].Revocation = r
+		}
+	}
+}
+
+// CheckDesignatedRevokers will try to confirm any of designated
+// revocation of entity. For this function to work, revocation
+// issuer's key should be found in keyring. First successfully
+// verified designated revocation is returned along with the key that
+// verified it.
+func FindVerifiedDesignatedRevoke(keyring KeyRing, entity *Entity) (*packet.Signature, *Key) {
+	for _, sig := range entity.UnverifiedRevocations {
+		if sig.IssuerKeyId == nil {
+			continue
+		}
+
+		issuerKeyId := *sig.IssuerKeyId
+		issuerFingerprint := sig.IssuerFingerprint
+		keys := keyring.KeysByIdUsage(issuerKeyId, issuerFingerprint, packet.KeyFlagSign)
+		if len(keys) == 0 {
+			continue
+		}
+		for _, key := range keys {
+			err := key.PublicKey.VerifyRevocationSignature(entity.PrimaryKey, sig)
+			if err == nil {
+				return sig, &key
+			}
+		}
+	}
+
+	return nil, nil
+}

vendor/github.com/keybase/go-crypto/openpgp/packet/compressed.go

@@ -8,9 +8,10 @@ import (
 	"compress/bzip2"
 	"compress/flate"
 	"compress/zlib"
-	"golang.org/x/crypto/openpgp/errors"
 	"io"
 	"strconv"
+
+	"github.com/keybase/go-crypto/openpgp/errors"
 )
 
 // Compressed represents a compressed OpenPGP packet. The decompressed contents

vendor/github.com/keybase/go-crypto/openpgp/packet/config.go

@@ -46,6 +46,9 @@ type Config struct {
 	// RSABits is the number of bits in new RSA keys made with NewEntity.
 	// If zero, then 2048 bit keys are created.
 	RSABits int
+	// ReuseSignatures tells us to reuse existing Signatures
+	// on serialized output.
+	ReuseSignaturesOnSerialize bool
 }
 
 func (c *Config) Random() io.Reader {
@@ -89,3 +92,7 @@ func (c *Config) PasswordHashIterations() int {
 	}
 	return c.S2KCount
 }
+
+func (c *Config) ReuseSignatures() bool {
+	return c != nil && c.ReuseSignaturesOnSerialize
+}

vendor/github.com/keybase/go-crypto/openpgp/packet/ecdh.go

@@ -0,0 +1,104 @@
+package packet
+
+import (
+	"bytes"
+	"io"
+	"math/big"
+
+	"github.com/keybase/go-crypto/openpgp/ecdh"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/s2k"
+)
+
+// ECDHKdfParams generates KDF parameters sequence for given
+// PublicKey. See https://tools.ietf.org/html/rfc6637#section-8
+func ECDHKdfParams(pub *PublicKey) []byte {
+	buf := new(bytes.Buffer)
+	oid := pub.ec.oid
+	buf.WriteByte(byte(len(oid)))
+	buf.Write(oid)
+	buf.WriteByte(18) // ECDH TYPE
+	pub.ecdh.serialize(buf)
+	buf.WriteString("Anonymous Sender    ")
+	buf.Write(pub.Fingerprint[:])
+	return buf.Bytes()
+}
+
+func decryptKeyECDH(priv *PrivateKey, X, Y *big.Int, C []byte) (out []byte, err error) {
+	ecdhpriv, ok := priv.PrivateKey.(*ecdh.PrivateKey)
+	if !ok {
+		return nil, errors.InvalidArgumentError("bad internal ECDH key")
+	}
+
+	Sx := ecdhpriv.DecryptShared(X, Y)
+
+	kdfParams := ECDHKdfParams(&priv.PublicKey)
+	hash, ok := s2k.HashIdToHash(byte(priv.ecdh.KdfHash))
+	if !ok {
+		return nil, errors.InvalidArgumentError("invalid hash id in private key")
+	}
+
+	key := ecdhpriv.KDF(Sx, kdfParams, hash)
+	keySize := CipherFunction(priv.ecdh.KdfAlgo).KeySize()
+
+	decrypted, err := ecdh.AESKeyUnwrap(key[:keySize], C)
+	if err != nil {
+		return nil, err
+	}
+
+	// We have to "read ahead" to discover real length of the
+	// encryption key and properly unpad buffer.
+	cipherFunc := CipherFunction(decrypted[0])
+	// +3 bytes = 1-byte cipher id and checksum 2-byte checksum.
+	out = ecdh.UnpadBuffer(decrypted, cipherFunc.KeySize()+3)
+	if out == nil {
+		return nil, errors.InvalidArgumentError("invalid padding while ECDH")
+	}
+	return out, nil
+}
+
+func serializeEncryptedKeyECDH(w io.Writer, rand io.Reader, header [10]byte, pub *PublicKey, keyBlock []byte) error {
+	ecdhpub := pub.PublicKey.(*ecdh.PublicKey)
+	kdfParams := ECDHKdfParams(pub)
+
+	hash, ok := s2k.HashIdToHash(byte(pub.ecdh.KdfHash))
+	if !ok {
+		return errors.InvalidArgumentError("invalid hash id in private key")
+	}
+
+	kdfKeySize := CipherFunction(pub.ecdh.KdfAlgo).KeySize()
+	Vx, Vy, C, err := ecdhpub.Encrypt(rand, kdfParams, keyBlock, hash, kdfKeySize)
+	if err != nil {
+		return err
+	}
+
+	mpis, mpiBitLen := ecdh.Marshal(ecdhpub.Curve, Vx, Vy)
+
+	packetLen := len(header) /* header length in bytes */
+	packetLen += 2 /* mpi length in bits */ + len(mpis)
+	packetLen += 1 /* ciphertext size in bytes */ + len(C)
+
+	err = serializeHeader(w, packetTypeEncryptedKey, packetLen)
+	if err != nil {
+		return err
+	}
+
+	_, err = w.Write(header[:])
+	if err != nil {
+		return err
+	}
+
+	_, err = w.Write([]byte{byte(mpiBitLen >> 8), byte(mpiBitLen)})
+	if err != nil {
+		return err
+	}
+
+	_, err = w.Write(mpis[:])
+	if err != nil {
+		return err
+	}
+
+	w.Write([]byte{byte(len(C))})
+	w.Write(C[:])
+	return nil
+}

vendor/github.com/keybase/go-crypto/openpgp/packet/encrypted_key.go

@@ -5,14 +5,15 @@
 package packet
 
 import (
-	"crypto/rsa"
 	"encoding/binary"
 	"io"
 	"math/big"
 	"strconv"
 
-	"golang.org/x/crypto/openpgp/elgamal"
-	"golang.org/x/crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/ecdh"
+	"github.com/keybase/go-crypto/openpgp/elgamal"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/rsa"
 )
 
 const encryptedKeyVersion = 3
@@ -26,6 +27,7 @@ type EncryptedKey struct {
 	Key        []byte         // only valid after a successful Decrypt
 
 	encryptedMPI1, encryptedMPI2 parsedMPI
+	ecdh_C                       []byte
 }
 
 func (e *EncryptedKey) parse(r io.Reader) (err error) {
@@ -48,9 +50,25 @@ func (e *EncryptedKey) parse(r io.Reader) (err error) {
 			return
 		}
 		e.encryptedMPI2.bytes, e.encryptedMPI2.bitLength, err = readMPI(r)
+	case PubKeyAlgoECDH:
+		e.encryptedMPI1.bytes, e.encryptedMPI1.bitLength, err = readMPI(r)
+		if err != nil {
+			return err
+		}
+		_, err = readFull(r, buf[:1]) // read C len (1 byte)
+		if err != nil {
+			return err
+		}
+		e.ecdh_C = make([]byte, int(buf[0]))
+		_, err = readFull(r, e.ecdh_C)
 	}
+
+	if err != nil {
+		return err
+	}
+
 	_, err = consumeAll(r)
-	return
+	return err
 }
 
 func checksumKeyMaterial(key []byte) uint16 {
@@ -77,6 +95,13 @@ func (e *EncryptedKey) Decrypt(priv *PrivateKey, config *Config) error {
 		c1 := new(big.Int).SetBytes(e.encryptedMPI1.bytes)
 		c2 := new(big.Int).SetBytes(e.encryptedMPI2.bytes)
 		b, err = elgamal.Decrypt(priv.PrivateKey.(*elgamal.PrivateKey), c1, c2)
+	case PubKeyAlgoECDH:
+		// Note: Unmarshal checks if point is on the curve.
+		c1, c2 := ecdh.Unmarshal(priv.PrivateKey.(*ecdh.PrivateKey).Curve, e.encryptedMPI1.bytes)
+		if c1 == nil {
+			return errors.InvalidArgumentError("failed to parse EC point for encryption key")
+		}
+		b, err = decryptKeyECDH(priv, c1, c2, e.ecdh_C)
 	default:
 		err = errors.InvalidArgumentError("cannot decrypted encrypted session key with private key of type " + strconv.Itoa(int(priv.PubKeyAlgo)))
 	}
@@ -147,6 +172,8 @@ func SerializeEncryptedKey(w io.Writer, pub *PublicKey, cipherFunc CipherFunctio
 		return serializeEncryptedKeyRSA(w, config.Random(), buf, pub.PublicKey.(*rsa.PublicKey), keyBlock)
 	case PubKeyAlgoElGamal:
 		return serializeEncryptedKeyElGamal(w, config.Random(), buf, pub.PublicKey.(*elgamal.PublicKey), keyBlock)
+	case PubKeyAlgoECDH:
+		return serializeEncryptedKeyECDH(w, config.Random(), buf, pub, keyBlock)
 	case PubKeyAlgoDSA, PubKeyAlgoRSASignOnly:
 		return errors.InvalidArgumentError("cannot encrypt to public key of type " + strconv.Itoa(int(pub.PubKeyAlgo)))
 	}

vendor/github.com/keybase/go-crypto/openpgp/packet/one_pass_signature.go

@@ -7,10 +7,11 @@ package packet
 import (
 	"crypto"
 	"encoding/binary"
-	"golang.org/x/crypto/openpgp/errors"
-	"golang.org/x/crypto/openpgp/s2k"
 	"io"
 	"strconv"
+
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/s2k"
 )
 
 // OnePassSignature represents a one-pass signature packet. See RFC 4880,

vendor/github.com/keybase/go-crypto/openpgp/packet/opaque.go

@@ -9,7 +9,7 @@ import (
 	"io"
 	"io/ioutil"
 
-	"golang.org/x/crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/errors"
 )
 
 // OpaquePacket represents an OpenPGP packet as raw, unparsed data. This is

vendor/github.com/keybase/go-crypto/openpgp/packet/packet.go

@@ -4,17 +4,19 @@
 
 // Package packet implements parsing and serialization of OpenPGP packets, as
 // specified in RFC 4880.
-package packet // import "golang.org/x/crypto/openpgp/packet"
+package packet // import "github.com/keybase/go-crypto/openpgp/packet"
 
 import (
 	"bufio"
 	"crypto/aes"
 	"crypto/cipher"
 	"crypto/des"
-	"golang.org/x/crypto/cast5"
-	"golang.org/x/crypto/openpgp/errors"
+	"crypto/elliptic"
 	"io"
 	"math/big"
+
+	"github.com/keybase/go-crypto/cast5"
+	"github.com/keybase/go-crypto/openpgp/errors"
 )
 
 // readFull is the same as io.ReadFull except that reading zero bytes returns
@@ -273,6 +275,8 @@ func consumeAll(r io.Reader) (n int64, err error) {
 			return
 		}
 	}
+
+	panic("unreachable")
 }
 
 // packetType represents the numeric ids of the different OpenPGP packet types. See
@@ -383,17 +387,18 @@ func Read(r io.Reader) (p Packet, err error) {
 type SignatureType uint8
 
 const (
-	SigTypeBinary            SignatureType = 0
-	SigTypeText                            = 1
-	SigTypeGenericCert                     = 0x10
-	SigTypePersonaCert                     = 0x11
-	SigTypeCasualCert                      = 0x12
-	SigTypePositiveCert                    = 0x13
-	SigTypeSubkeyBinding                   = 0x18
-	SigTypePrimaryKeyBinding               = 0x19
-	SigTypeDirectSignature                 = 0x1F
-	SigTypeKeyRevocation                   = 0x20
-	SigTypeSubkeyRevocation                = 0x28
+	SigTypeBinary             SignatureType = 0
+	SigTypeText                             = 1
+	SigTypeGenericCert                      = 0x10
+	SigTypePersonaCert                      = 0x11
+	SigTypeCasualCert                       = 0x12
+	SigTypePositiveCert                     = 0x13
+	SigTypeSubkeyBinding                    = 0x18
+	SigTypePrimaryKeyBinding                = 0x19
+	SigTypeDirectSignature                  = 0x1F
+	SigTypeKeyRevocation                    = 0x20
+	SigTypeSubkeyRevocation                 = 0x28
+	SigTypeIdentityRevocation               = 0x30
 )
 
 // PublicKeyAlgorithm represents the different public key system specified for
@@ -410,13 +415,15 @@ const (
 	// RFC 6637, Section 5.
 	PubKeyAlgoECDH  PublicKeyAlgorithm = 18
 	PubKeyAlgoECDSA PublicKeyAlgorithm = 19
+	// RFC -1
+	PubKeyAlgoEdDSA PublicKeyAlgorithm = 22
 )
 
 // CanEncrypt returns true if it's possible to encrypt a message to a public
 // key of the given type.
 func (pka PublicKeyAlgorithm) CanEncrypt() bool {
 	switch pka {
-	case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoElGamal:
+	case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoElGamal, PubKeyAlgoECDH:
 		return true
 	}
 	return false
@@ -426,7 +433,7 @@ func (pka PublicKeyAlgorithm) CanEncrypt() bool {
 // sign a message.
 func (pka PublicKeyAlgorithm) CanSign() bool {
 	switch pka {
-	case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA, PubKeyAlgoECDSA:
+	case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA, PubKeyAlgoECDSA, PubKeyAlgoEdDSA:
 		return true
 	}
 	return false
@@ -520,6 +527,25 @@ func writeMPI(w io.Writer, bitLength uint16, mpiBytes []byte) (err error) {
 	return
 }
 
+func WritePaddedBigInt(w io.Writer, length int, X *big.Int) (n int, err error) {
+	bytes := X.Bytes()
+	n1, err := w.Write(make([]byte, length-len(bytes)))
+	if err != nil {
+		return n1, err
+	}
+	n2, err := w.Write(bytes)
+	if err != nil {
+		return n2, err
+	}
+	return (n1 + n2), err
+}
+
+// Minimum number of bytes to fit the curve coordinates. All
+// coordinates have to be 0-padded to this length.
+func mpiPointByteLength(curve elliptic.Curve) int {
+	return (curve.Params().P.BitLen() + 7) / 8
+}
+
 // writeBig serializes a *big.Int to w.
 func writeBig(w io.Writer, i *big.Int) error {
 	return writeMPI(w, uint16(i.BitLen()), i.Bytes())

vendor/github.com/keybase/go-crypto/openpgp/packet/private_key.go

@@ -6,21 +6,23 @@ package packet
 
 import (
 	"bytes"
-	"crypto"
 	"crypto/cipher"
 	"crypto/dsa"
 	"crypto/ecdsa"
-	"crypto/rsa"
 	"crypto/sha1"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"math/big"
 	"strconv"
 	"time"
 
-	"golang.org/x/crypto/openpgp/elgamal"
-	"golang.org/x/crypto/openpgp/errors"
-	"golang.org/x/crypto/openpgp/s2k"
+	"github.com/keybase/go-crypto/ed25519"
+	"github.com/keybase/go-crypto/openpgp/ecdh"
+	"github.com/keybase/go-crypto/openpgp/elgamal"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/s2k"
+	"github.com/keybase/go-crypto/rsa"
 )
 
 // PrivateKey represents a possibly encrypted private key. See RFC 4880,
@@ -31,9 +33,32 @@ type PrivateKey struct {
 	encryptedData []byte
 	cipher        CipherFunction
 	s2k           func(out, in []byte)
-	PrivateKey    interface{} // An *{rsa|dsa|ecdsa}.PrivateKey or a crypto.Signer.
+	PrivateKey    interface{} // An *rsa.PrivateKey or *dsa.PrivateKey.
 	sha1Checksum  bool
 	iv            []byte
+	s2kHeader     []byte
+}
+
+type EdDSAPrivateKey struct {
+	PrivateKey
+	seed parsedMPI
+}
+
+func (e *EdDSAPrivateKey) Sign(digest []byte) (R, S []byte, err error) {
+	r := bytes.NewReader(e.seed.bytes)
+	publicKey, privateKey, err := ed25519.GenerateKey(r)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	if !bytes.Equal(publicKey, e.PublicKey.edk.p.bytes[1:]) { // [1:] because [0] is 0x40 mpi header
+		return nil, nil, errors.UnsupportedError("EdDSA: Private key does not match public key.")
+	}
+
+	sig := ed25519.Sign(privateKey, digest)
+
+	sigLen := ed25519.SignatureSize / 2
+	return sig[:sigLen], sig[sigLen:], nil
 }
 
 func NewRSAPrivateKey(currentTime time.Time, priv *rsa.PrivateKey) *PrivateKey {
@@ -64,23 +89,6 @@ func NewECDSAPrivateKey(currentTime time.Time, priv *ecdsa.PrivateKey) *PrivateK
 	return pk
 }
 
-// NewSignerPrivateKey creates a sign-only PrivateKey from a crypto.Signer that
-// implements RSA or ECDSA.
-func NewSignerPrivateKey(currentTime time.Time, signer crypto.Signer) *PrivateKey {
-	pk := new(PrivateKey)
-	switch pubkey := signer.Public().(type) {
-	case rsa.PublicKey:
-		pk.PublicKey = *NewRSAPublicKey(currentTime, &pubkey)
-		pk.PubKeyAlgo = PubKeyAlgoRSASignOnly
-	case ecdsa.PublicKey:
-		pk.PublicKey = *NewECDSAPublicKey(currentTime, &pubkey)
-	default:
-		panic("openpgp: unknown crypto.Signer type in NewSignerPrivateKey")
-	}
-	pk.PrivateKey = signer
-	return pk
-}
-
 func (pk *PrivateKey) parse(r io.Reader) (err error) {
 	err = (&pk.PublicKey).parse(r)
 	if err != nil {
@@ -112,10 +120,16 @@ func (pk *PrivateKey) parse(r io.Reader) (err error) {
 		if s2kType == 254 {
 			pk.sha1Checksum = true
 		}
+		// S2K == nil implies that we got a "GNU Dummy" S2K. For instance,
+		// because our master secret key is on a USB key in a vault somewhere.
+		// In that case, there is no further data to consume here.
+		if pk.s2k == nil {
+			pk.Encrypted = false
+			return
+		}
 	default:
 		return errors.UnsupportedError("deprecated s2k function in private key")
 	}
-
 	if pk.Encrypted {
 		blockSize := pk.cipher.blockSize()
 		if blockSize == 0 {
@@ -148,31 +162,105 @@ func mod64kHash(d []byte) uint16 {
 	return h
 }
 
+// Encrypt is the counterpart to the Decrypt() method below. It encrypts
+// the private key with the provided passphrase. If config is nil, then
+// the standard, and sensible, defaults apply.
+//
+// A key will be derived from the given passphrase using S2K Specifier
+// Type 3 (Iterated + Salted, see RFC-4880 Sec. 3.7.1.3). This choice
+// is hardcoded in s2k.Serialize(). S2KCount is hardcoded to 0, which is
+// equivalent to 65536. And the hash algorithm for key-derivation can be
+// set with config. The encrypted PrivateKey, using the algorithm specified
+// in config (if provided), is written out to the encryptedData member.
+// When Serialize() is called, this encryptedData member will be
+// serialized, using S2K Usage value of 254, and thus SHA1 checksum.
+func (pk *PrivateKey) Encrypt(passphrase []byte, config *Config) (err error) {
+	if pk.PrivateKey == nil {
+		return errors.InvalidArgumentError("there is no private key to encrypt")
+	}
+
+	pk.sha1Checksum = true
+	pk.cipher = config.Cipher()
+	s2kConfig := s2k.Config{
+		Hash:     config.Hash(),
+		S2KCount: 0,
+	}
+	s2kBuf := bytes.NewBuffer(nil)
+	derivedKey := make([]byte, pk.cipher.KeySize())
+	err = s2k.Serialize(s2kBuf, derivedKey, config.Random(), passphrase, &s2kConfig)
+	if err != nil {
+		return err
+	}
+
+	pk.s2kHeader = s2kBuf.Bytes()
+	// No good way to set pk.s2k but to call s2k.Parse(),
+	// even though we have all the information here, but
+	// most of the functions needed are private to s2k.
+	pk.s2k, err = s2k.Parse(s2kBuf)
+	pk.iv = make([]byte, pk.cipher.blockSize())
+	if _, err = config.Random().Read(pk.iv); err != nil {
+		return err
+	}
+
+	privateKeyBuf := bytes.NewBuffer(nil)
+	if err = pk.serializePrivateKey(privateKeyBuf); err != nil {
+		return err
+	}
+
+	checksum := sha1.Sum(privateKeyBuf.Bytes())
+	if _, err = privateKeyBuf.Write(checksum[:]); err != nil {
+		return err
+	}
+
+	pkData := privateKeyBuf.Bytes()
+	block := pk.cipher.new(derivedKey)
+	pk.encryptedData = make([]byte, len(pkData))
+	cfb := cipher.NewCFBEncrypter(block, pk.iv)
+	cfb.XORKeyStream(pk.encryptedData, pkData)
+	pk.Encrypted = true
+	return nil
+}
+
 func (pk *PrivateKey) Serialize(w io.Writer) (err error) {
-	// TODO(agl): support encrypted private keys
 	buf := bytes.NewBuffer(nil)
 	err = pk.PublicKey.serializeWithoutHeaders(buf)
 	if err != nil {
 		return
 	}
-	buf.WriteByte(0 /* no encryption */)
 
 	privateKeyBuf := bytes.NewBuffer(nil)
 
-	switch priv := pk.PrivateKey.(type) {
-	case *rsa.PrivateKey:
-		err = serializeRSAPrivateKey(privateKeyBuf, priv)
-	case *dsa.PrivateKey:
-		err = serializeDSAPrivateKey(privateKeyBuf, priv)
-	case *elgamal.PrivateKey:
-		err = serializeElGamalPrivateKey(privateKeyBuf, priv)
-	case *ecdsa.PrivateKey:
-		err = serializeECDSAPrivateKey(privateKeyBuf, priv)
-	default:
-		err = errors.InvalidArgumentError("unknown private key type")
-	}
-	if err != nil {
-		return
+	if pk.PrivateKey == nil {
+		_, err = buf.Write([]byte{
+			254,           // SHA-1 Convention
+			9,             // Encryption scheme (AES256)
+			101,           // GNU Extensions
+			2,             // Hash value (SHA1)
+			'G', 'N', 'U', // "GNU" as a string
+			1, // Extension type 1001 (minus 1000)
+		})
+	} else if pk.Encrypted {
+		_, err = buf.Write([]byte{
+			254,             // SHA-1 Convention
+			byte(pk.cipher), // Encryption scheme
+		})
+		if err != nil {
+			return err
+		}
+		if _, err = buf.Write(pk.s2kHeader); err != nil {
+			return err
+		}
+		if _, err = buf.Write(pk.iv); err != nil {
+			return err
+		}
+		if _, err = privateKeyBuf.Write(pk.encryptedData); err != nil {
+			return err
+		}
+	} else {
+		buf.WriteByte(0 /* no encryption */)
+		if err = pk.serializePrivateKey(privateKeyBuf); err != nil {
+			return err
+		}
 	}
 
 	ptype := packetTypePrivateKey
@@ -181,7 +269,11 @@ func (pk *PrivateKey) Serialize(w io.Writer) (err error) {
 	if pk.IsSubkey {
 		ptype = packetTypePrivateSubkey
 	}
-	err = serializeHeader(w, ptype, len(contents)+len(privateKeyBytes)+2)
+	totalLen := len(contents) + len(privateKeyBytes)
+	if !pk.Encrypted {
+		totalLen += 2
+	}
+	err = serializeHeader(w, ptype, totalLen)
 	if err != nil {
 		return
 	}
@@ -194,15 +286,38 @@ func (pk *PrivateKey) Serialize(w io.Writer) (err error) {
 		return
 	}
 
-	checksum := mod64kHash(privateKeyBytes)
-	var checksumBytes [2]byte
-	checksumBytes[0] = byte(checksum >> 8)
-	checksumBytes[1] = byte(checksum)
-	_, err = w.Write(checksumBytes[:])
+	if len(privateKeyBytes) > 0 && !pk.Encrypted {
+		checksum := mod64kHash(privateKeyBytes)
+		var checksumBytes [2]byte
+		checksumBytes[0] = byte(checksum >> 8)
+		checksumBytes[1] = byte(checksum)
+		_, err = w.Write(checksumBytes[:])
+	}
 
 	return
 }
 
+func (pk *PrivateKey) serializePrivateKey(w io.Writer) (err error) {
+	switch priv := pk.PrivateKey.(type) {
+	case *rsa.PrivateKey:
+		err = serializeRSAPrivateKey(w, priv)
+	case *dsa.PrivateKey:
+		err = serializeDSAPrivateKey(w, priv)
+	case *elgamal.PrivateKey:
+		err = serializeElGamalPrivateKey(w, priv)
+	case *ecdsa.PrivateKey:
+		err = serializeECDSAPrivateKey(w, priv)
+	case *ecdh.PrivateKey:
+		err = serializeECDHPrivateKey(w, priv)
+	case *EdDSAPrivateKey:
+		err = serializeEdDSAPrivateKey(w, priv)
+	default:
+		err = errors.InvalidArgumentError("unknown private key type")
+	}
+
+	return err
+}
+
 func serializeRSAPrivateKey(w io.Writer, priv *rsa.PrivateKey) error {
 	err := writeBig(w, priv.D)
 	if err != nil {
@@ -231,11 +346,23 @@ func serializeECDSAPrivateKey(w io.Writer, priv *ecdsa.PrivateKey) error {
 	return writeBig(w, priv.D)
 }
 
+func serializeECDHPrivateKey(w io.Writer, priv *ecdh.PrivateKey) error {
+	return writeBig(w, priv.X)
+}
+
+func serializeEdDSAPrivateKey(w io.Writer, priv *EdDSAPrivateKey) error {
+	return writeMPI(w, priv.seed.bitLength, priv.seed.bytes)
+}
+
 // Decrypt decrypts an encrypted private key using a passphrase.
 func (pk *PrivateKey) Decrypt(passphrase []byte) error {
 	if !pk.Encrypted {
 		return nil
 	}
+	// For GNU Dummy S2K, there's no key here, so don't do anything.
+	if pk.s2k == nil {
+		return nil
+	}
 
 	key := make([]byte, pk.cipher.KeySize())
 	pk.s2k(key, passphrase)
@@ -284,6 +411,10 @@ func (pk *PrivateKey) parsePrivateKey(data []byte) (err error) {
 		return pk.parseElGamalPrivateKey(data)
 	case PubKeyAlgoECDSA:
 		return pk.parseECDSAPrivateKey(data)
+	case PubKeyAlgoECDH:
+		return pk.parseECDHPrivateKey(data)
+	case PubKeyAlgoEdDSA:
+		return pk.parseEdDSAPrivateKey(data)
 	}
 	panic("impossible")
 }
@@ -360,8 +491,28 @@ func (pk *PrivateKey) parseElGamalPrivateKey(data []byte) (err error) {
 	return nil
 }
 
+func (pk *PrivateKey) parseECDHPrivateKey(data []byte) (err error) {
+	pub := pk.PublicKey.PublicKey.(*ecdh.PublicKey)
+	priv := new(ecdh.PrivateKey)
+	priv.PublicKey = *pub
+
+	buf := bytes.NewBuffer(data)
+	d, _, err := readMPI(buf)
+	if err != nil {
+		return
+	}
+
+	priv.X = new(big.Int).SetBytes(d)
+	pk.PrivateKey = priv
+	pk.Encrypted = false
+	pk.encryptedData = nil
+	return nil
+}
+
 func (pk *PrivateKey) parseECDSAPrivateKey(data []byte) (err error) {
 	ecdsaPub := pk.PublicKey.PublicKey.(*ecdsa.PublicKey)
+	ecdsaPriv := new(ecdsa.PrivateKey)
+	ecdsaPriv.PublicKey = *ecdsaPub
 
 	buf := bytes.NewBuffer(data)
 	d, _, err := readMPI(buf)
@@ -369,10 +520,29 @@ func (pk *PrivateKey) parseECDSAPrivateKey(data []byte) (err error) {
 		return
 	}
 
-	pk.PrivateKey = &ecdsa.PrivateKey{
-		PublicKey: *ecdsaPub,
-		D:         new(big.Int).SetBytes(d),
+	ecdsaPriv.D = new(big.Int).SetBytes(d)
+	pk.PrivateKey = ecdsaPriv
+	pk.Encrypted = false
+	pk.encryptedData = nil
+
+	return nil
+}
+
+func (pk *PrivateKey) parseEdDSAPrivateKey(data []byte) (err error) {
+	eddsaPriv := new(EdDSAPrivateKey)
+	eddsaPriv.PublicKey = pk.PublicKey
+
+	buf := bytes.NewBuffer(data)
+	eddsaPriv.seed.bytes, eddsaPriv.seed.bitLength, err = readMPI(buf)
+	if err != nil {
+		return err
 	}
+
+	if bLen := len(eddsaPriv.seed.bytes); bLen != 32 { // 32 bytes private part of ed25519 key.
+		return errors.UnsupportedError(fmt.Sprintf("Unexpected EdDSA private key length: %d", bLen))
+	}
+
+	pk.PrivateKey = eddsaPriv
 	pk.Encrypted = false
 	pk.encryptedData = nil
 

vendor/github.com/keybase/go-crypto/openpgp/packet/public_key.go

@@ -10,7 +10,6 @@ import (
 	"crypto/dsa"
 	"crypto/ecdsa"
 	"crypto/elliptic"
-	"crypto/rsa"
 	"crypto/sha1"
 	_ "crypto/sha256"
 	_ "crypto/sha512"
@@ -22,8 +21,13 @@ import (
 	"strconv"
 	"time"
 
-	"golang.org/x/crypto/openpgp/elgamal"
-	"golang.org/x/crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/brainpool"
+	"github.com/keybase/go-crypto/curve25519"
+	"github.com/keybase/go-crypto/ed25519"
+	"github.com/keybase/go-crypto/openpgp/ecdh"
+	"github.com/keybase/go-crypto/openpgp/elgamal"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/rsa"
 )
 
 var (
@@ -33,9 +37,19 @@ var (
 	oidCurveP384 []byte = []byte{0x2B, 0x81, 0x04, 0x00, 0x22}
 	// NIST curve P-521
 	oidCurveP521 []byte = []byte{0x2B, 0x81, 0x04, 0x00, 0x23}
+	// Brainpool curve P-256r1
+	oidCurveP256r1 []byte = []byte{0x2B, 0x24, 0x03, 0x03, 0x02, 0x08, 0x01, 0x01, 0x07}
+	// Brainpool curve P-384r1
+	oidCurveP384r1 []byte = []byte{0x2B, 0x24, 0x03, 0x03, 0x02, 0x08, 0x01, 0x01, 0x0B}
+	// Brainpool curve P-512r1
+	oidCurveP512r1 []byte = []byte{0x2B, 0x24, 0x03, 0x03, 0x02, 0x08, 0x01, 0x01, 0x0D}
+	// EdDSA
+	oidEdDSA []byte = []byte{0x2B, 0x06, 0x01, 0x04, 0x01, 0xDA, 0x47, 0x0F, 0x01}
+	// cv25519
+	oidCurve25519 []byte = []byte{0x2B, 0x06, 0x01, 0x04, 0x01, 0x97, 0x55, 0x01, 0x05, 0x01}
 )
 
-const maxOIDLength = 8
+const maxOIDLength = 10
 
 // ecdsaKey stores the algorithm-specific fields for ECDSA keys.
 // as defined in RFC 6637, Section 9.
@@ -46,6 +60,38 @@ type ecdsaKey struct {
 	p parsedMPI
 }
 
+type edDSAkey struct {
+	ecdsaKey
+}
+
+func copyFrontFill(dst, src []byte, length int) int {
+	if srcLen := len(src); srcLen < length {
+		return copy(dst[length-srcLen:], src[:])
+	} else {
+		return copy(dst[:], src[:])
+	}
+}
+
+func (e *edDSAkey) Verify(payload []byte, r parsedMPI, s parsedMPI) bool {
+	const halfSigSize = ed25519.SignatureSize / 2
+	var sig [ed25519.SignatureSize]byte
+
+	// NOTE: The first byte is 0x40 - MPI header
+	// TODO: Maybe clean the code up and use 0x40 as a header when
+	// reading and keep only actual number in p field. Find out how
+	// other MPIs are stored.
+	key := e.p.bytes[1:]
+
+	// Note: it may happen that R + S do not form 64-byte signature buffer that
+	// ed25519 expects, but because we copy it over to an array of exact size,
+	// we will always pass correctly sized slice to Verify. Slice too short
+	// would make ed25519 panic().
+	copyFrontFill(sig[:halfSigSize], r.bytes, halfSigSize)
+	copyFrontFill(sig[halfSigSize:], s.bytes, halfSigSize)
+
+	return ed25519.Verify(key, payload, sig[:])
+}
+
 // parseOID reads the OID for the curve as defined in RFC 6637, Section 9.
 func parseOID(r io.Reader) (oid []byte, err error) {
 	buf := make([]byte, maxOIDLength)
@@ -67,7 +113,7 @@ func (f *ecdsaKey) parse(r io.Reader) (err error) {
 		return err
 	}
 	f.p.bytes, f.p.bitLength, err = readMPI(r)
-	return
+	return err
 }
 
 func (f *ecdsaKey) serialize(w io.Writer) (err error) {
@@ -80,17 +126,34 @@ func (f *ecdsaKey) serialize(w io.Writer) (err error) {
 	return writeMPIs(w, f.p)
 }
 
+func getCurveByOid(oid []byte) elliptic.Curve {
+	switch {
+	case bytes.Equal(oid, oidCurveP256):
+		return elliptic.P256()
+	case bytes.Equal(oid, oidCurveP384):
+		return elliptic.P384()
+	case bytes.Equal(oid, oidCurveP521):
+		return elliptic.P521()
+	case bytes.Equal(oid, oidCurveP256r1):
+		return brainpool.P256r1()
+	case bytes.Equal(oid, oidCurveP384r1):
+		return brainpool.P384r1()
+	case bytes.Equal(oid, oidCurveP512r1):
+		return brainpool.P512r1()
+	case bytes.Equal(oid, oidCurve25519):
+		return curve25519.Cv25519()
+	default:
+		return nil
+	}
+}
+
 func (f *ecdsaKey) newECDSA() (*ecdsa.PublicKey, error) {
-	var c elliptic.Curve
-	if bytes.Equal(f.oid, oidCurveP256) {
-		c = elliptic.P256()
-	} else if bytes.Equal(f.oid, oidCurveP384) {
-		c = elliptic.P384()
-	} else if bytes.Equal(f.oid, oidCurveP521) {
-		c = elliptic.P521()
-	} else {
+	var c = getCurveByOid(f.oid)
+	// Curve25519 should not be used in ECDSA.
+	if c == nil || bytes.Equal(f.oid, oidCurve25519) {
 		return nil, errors.UnsupportedError(fmt.Sprintf("unsupported oid: %x", f.oid))
 	}
+	// Note: Unmarshal already checks if point is on curve.
 	x, y := elliptic.Unmarshal(c, f.p.bytes)
 	if x == nil {
 		return nil, errors.UnsupportedError("failed to parse EC point")
@@ -98,6 +161,20 @@ func (f *ecdsaKey) newECDSA() (*ecdsa.PublicKey, error) {
 	return &ecdsa.PublicKey{Curve: c, X: x, Y: y}, nil
 }
 
+func (f *ecdsaKey) newECDH() (*ecdh.PublicKey, error) {
+	var c = getCurveByOid(f.oid)
+	if c == nil {
+		return nil, errors.UnsupportedError(fmt.Sprintf("unsupported oid: %x", f.oid))
+	}
+	// ecdh.Unmarshal handles unmarshaling for all curve types. It
+	// also checks if point is on curve.
+	x, y := ecdh.Unmarshal(c, f.p.bytes)
+	if x == nil {
+		return nil, errors.UnsupportedError("failed to parse EC point")
+	}
+	return &ecdh.PublicKey{Curve: c, X: x, Y: y}, nil
+}
+
 func (f *ecdsaKey) byteLen() int {
 	return 1 + len(f.oid) + 2 + len(f.p.bytes)
 }
@@ -163,6 +240,9 @@ type PublicKey struct {
 	// RFC 6637 fields
 	ec   *ecdsaKey
 	ecdh *ecdhKdf
+
+	// EdDSA fields (no RFC available), uses ecdsa scaffolding
+	edk *edDSAkey
 }
 
 // signingKey provides a convenient abstraction over signature verification
@@ -172,21 +252,28 @@ type signingKey interface {
 	serializeWithoutHeaders(io.Writer) error
 }
 
-func fromBig(n *big.Int) parsedMPI {
+func FromBig(n *big.Int) parsedMPI {
 	return parsedMPI{
 		bytes:     n.Bytes(),
 		bitLength: uint16(n.BitLen()),
 	}
 }
 
+func FromBytes(bytes []byte) parsedMPI {
+	return parsedMPI{
+		bytes:     bytes,
+		bitLength: uint16(8 * len(bytes)),
+	}
+}
+
 // NewRSAPublicKey returns a PublicKey that wraps the given rsa.PublicKey.
 func NewRSAPublicKey(creationTime time.Time, pub *rsa.PublicKey) *PublicKey {
 	pk := &PublicKey{
 		CreationTime: creationTime,
 		PubKeyAlgo:   PubKeyAlgoRSA,
 		PublicKey:    pub,
-		n:            fromBig(pub.N),
-		e:            fromBig(big.NewInt(int64(pub.E))),
+		n:            FromBig(pub.N),
+		e:            FromBig(big.NewInt(int64(pub.E))),
 	}
 
 	pk.setFingerPrintAndKeyId()
@@ -199,25 +286,38 @@ func NewDSAPublicKey(creationTime time.Time, pub *dsa.PublicKey) *PublicKey {
 		CreationTime: creationTime,
 		PubKeyAlgo:   PubKeyAlgoDSA,
 		PublicKey:    pub,
-		p:            fromBig(pub.P),
-		q:            fromBig(pub.Q),
-		g:            fromBig(pub.G),
-		y:            fromBig(pub.Y),
+		p:            FromBig(pub.P),
+		q:            FromBig(pub.Q),
+		g:            FromBig(pub.G),
+		y:            FromBig(pub.Y),
 	}
 
 	pk.setFingerPrintAndKeyId()
 	return pk
 }
 
+// check EdDSA public key material.
+// There is currently no RFC for it, but it doesn't mean it's not
+// implemented or in use.
+func (e *edDSAkey) check() error {
+	if !bytes.Equal(e.oid, oidEdDSA) {
+		return errors.UnsupportedError(fmt.Sprintf("Bad OID for EdDSA key: %v", e.oid))
+	}
+	if bLen := len(e.p.bytes); bLen != 33 { // 32 bytes for ed25519 key and 1 byte for 0x40 header
+		return errors.UnsupportedError(fmt.Sprintf("Unexpected EdDSA public key length: %d", bLen))
+	}
+	return nil
+}
+
 // NewElGamalPublicKey returns a PublicKey that wraps the given elgamal.PublicKey.
 func NewElGamalPublicKey(creationTime time.Time, pub *elgamal.PublicKey) *PublicKey {
 	pk := &PublicKey{
 		CreationTime: creationTime,
 		PubKeyAlgo:   PubKeyAlgoElGamal,
 		PublicKey:    pub,
-		p:            fromBig(pub.P),
-		g:            fromBig(pub.G),
-		y:            fromBig(pub.Y),
+		p:            FromBig(pub.P),
+		g:            FromBig(pub.G),
+		y:            FromBig(pub.Y),
 	}
 
 	pk.setFingerPrintAndKeyId()
@@ -231,7 +331,6 @@ func NewECDSAPublicKey(creationTime time.Time, pub *ecdsa.PublicKey) *PublicKey
 		PublicKey:    pub,
 		ec:           new(ecdsaKey),
 	}
-
 	switch pub.Curve {
 	case elliptic.P256():
 		pk.ec.oid = oidCurveP256
@@ -239,10 +338,13 @@ func NewECDSAPublicKey(creationTime time.Time, pub *ecdsa.PublicKey) *PublicKey
 		pk.ec.oid = oidCurveP384
 	case elliptic.P521():
 		pk.ec.oid = oidCurveP521
-	default:
-		panic("unknown elliptic curve")
+	case brainpool.P256r1():
+		pk.ec.oid = oidCurveP256r1
+	case brainpool.P384r1():
+		pk.ec.oid = oidCurveP384r1
+	case brainpool.P512r1():
+		pk.ec.oid = oidCurveP512r1
 	}
-
 	pk.ec.p.bytes = elliptic.Marshal(pub.Curve, pub.X, pub.Y)
 	pk.ec.p.bitLength = uint16(8 * len(pk.ec.p.bytes))
 
@@ -269,6 +371,12 @@ func (pk *PublicKey) parse(r io.Reader) (err error) {
 		err = pk.parseDSA(r)
 	case PubKeyAlgoElGamal:
 		err = pk.parseElGamal(r)
+	case PubKeyAlgoEdDSA:
+		pk.edk = new(edDSAkey)
+		if err = pk.edk.parse(r); err != nil {
+			return err
+		}
+		err = pk.edk.check()
 	case PubKeyAlgoECDSA:
 		pk.ec = new(ecdsaKey)
 		if err = pk.ec.parse(r); err != nil {
@@ -284,8 +392,7 @@ func (pk *PublicKey) parse(r io.Reader) (err error) {
 		if err = pk.ecdh.parse(r); err != nil {
 			return
 		}
-		// The ECDH key is stored in an ecdsa.PublicKey for convenience.
-		pk.PublicKey, err = pk.ec.newECDSA()
+		pk.PublicKey, err = pk.ec.newECDH()
 	default:
 		err = errors.UnsupportedError("public key type: " + strconv.Itoa(int(pk.PubKeyAlgo)))
 	}
@@ -318,7 +425,7 @@ func (pk *PublicKey) parseRSA(r io.Reader) (err error) {
 		return
 	}
 
-	if len(pk.e.bytes) > 3 {
+	if len(pk.e.bytes) > 7 {
 		err = errors.UnsupportedError("large public exponent")
 		return
 	}
@@ -328,7 +435,7 @@ func (pk *PublicKey) parseRSA(r io.Reader) (err error) {
 	}
 	for i := 0; i < len(pk.e.bytes); i++ {
 		rsa.E <<= 8
-		rsa.E |= int(pk.e.bytes[i])
+		rsa.E |= int64(pk.e.bytes[i])
 	}
 	pk.PublicKey = rsa
 	return
@@ -410,6 +517,8 @@ func (pk *PublicKey) SerializeSignaturePrefix(h io.Writer) {
 	case PubKeyAlgoECDH:
 		pLength += uint16(pk.ec.byteLen())
 		pLength += uint16(pk.ecdh.byteLen())
+	case PubKeyAlgoEdDSA:
+		pLength += uint16(pk.edk.byteLen())
 	default:
 		panic("unknown public key algorithm")
 	}
@@ -439,6 +548,8 @@ func (pk *PublicKey) Serialize(w io.Writer) (err error) {
 	case PubKeyAlgoECDH:
 		length += pk.ec.byteLen()
 		length += pk.ecdh.byteLen()
+	case PubKeyAlgoEdDSA:
+		length += pk.edk.byteLen()
 	default:
 		panic("unknown public key algorithm")
 	}
@@ -480,6 +591,8 @@ func (pk *PublicKey) serializeWithoutHeaders(w io.Writer) (err error) {
 		return writeMPIs(w, pk.p, pk.g, pk.y)
 	case PubKeyAlgoECDSA:
 		return pk.ec.serialize(w)
+	case PubKeyAlgoEdDSA:
+		return pk.edk.serialize(w)
 	case PubKeyAlgoECDH:
 		if err = pk.ec.serialize(w); err != nil {
 			return
@@ -504,9 +617,18 @@ func (pk *PublicKey) VerifySignature(signed hash.Hash, sig *Signature) (err erro
 	signed.Write(sig.HashSuffix)
 	hashBytes := signed.Sum(nil)
 
-	if hashBytes[0] != sig.HashTag[0] || hashBytes[1] != sig.HashTag[1] {
-		return errors.SignatureError("hash tag doesn't match")
-	}
+	// NOTE(maxtaco) 2016-08-22
+	//
+	// We used to do this:
+	//
+	// if hashBytes[0] != sig.HashTag[0] || hashBytes[1] != sig.HashTag[1] {
+	//	  return errors.SignatureError("hash tag doesn't match")
+	// }
+	//
+	// But don't do anything in this case. Some GPGs generate bad
+	// 2-byte hash prefixes, but GPG also doesn't seem to care on
+	// import. See BrentMaxwell's key. I think it's safe to disable
+	// this check!
 
 	if pk.PubKeyAlgo != sig.PubKeyAlgo {
 		return errors.InvalidArgumentError("public key and signature use different algorithms")
@@ -537,9 +659,15 @@ func (pk *PublicKey) VerifySignature(signed hash.Hash, sig *Signature) (err erro
 			return errors.SignatureError("ECDSA verification failure")
 		}
 		return nil
+	case PubKeyAlgoEdDSA:
+		if !pk.edk.Verify(hashBytes, sig.EdDSASigR, sig.EdDSASigS) {
+			return errors.SignatureError("EdDSA verification failure")
+		}
+		return nil
 	default:
 		return errors.SignatureError("Unsupported public key algorithm used in signature")
 	}
+	panic("unreachable")
 }
 
 // VerifySignatureV3 returns nil iff sig is a valid signature, made by this
@@ -584,6 +712,7 @@ func (pk *PublicKey) VerifySignatureV3(signed hash.Hash, sig *SignatureV3) (err
 	default:
 		panic("shouldn't happen")
 	}
+	panic("unreachable")
 }
 
 // keySignatureHash returns a Hash of the message that needs to be signed for
@@ -594,12 +723,18 @@ func keySignatureHash(pk, signed signingKey, hashFunc crypto.Hash) (h hash.Hash,
 	}
 	h = hashFunc.New()
 
+	updateKeySignatureHash(pk, signed, h)
+
+	return
+}
+
+// updateKeySignatureHash does the actual hash updates for keySignatureHash.
+func updateKeySignatureHash(pk, signed signingKey, h hash.Hash) {
 	// RFC 4880, section 5.2.4
 	pk.SerializeSignaturePrefix(h)
 	pk.serializeWithoutHeaders(h)
 	signed.SerializeSignaturePrefix(h)
 	signed.serializeWithoutHeaders(h)
-	return
 }
 
 // VerifyKeySignature returns nil iff sig is a valid signature, made by this
@@ -614,6 +749,19 @@ func (pk *PublicKey) VerifyKeySignature(signed *PublicKey, sig *Signature) error
 	}
 
 	if sig.FlagSign {
+
+		// BUG(maxtaco)
+		//
+		// We should check for more than FlagsSign here, because if
+		// you read keys.go, we can sometimes use signing subkeys even if they're
+		// not explicitly flagged as such. However, so doing fails lots of currently
+		// working tests, so I'm not going to do much here.
+		//
+		// In other words, we should have this disjunction in the condition above:
+		//
+		//    || (!sig.FlagsValid && pk.PubKeyAlgo.CanSign()) {
+		//
+
 		// Signing subkeys must be cross-signed. See
 		// https://www.gnupg.org/faq/subkey-cross-certify.html.
 		if sig.EmbeddedSignature == nil {
@@ -648,14 +796,27 @@ func keyRevocationHash(pk signingKey, hashFunc crypto.Hash) (h hash.Hash, err er
 
 // VerifyRevocationSignature returns nil iff sig is a valid signature, made by this
 // public key.
-func (pk *PublicKey) VerifyRevocationSignature(sig *Signature) (err error) {
-	h, err := keyRevocationHash(pk, sig.Hash)
+func (pk *PublicKey) VerifyRevocationSignature(revokedKey *PublicKey, sig *Signature) (err error) {
+	h, err := keyRevocationHash(revokedKey, sig.Hash)
 	if err != nil {
 		return err
 	}
 	return pk.VerifySignature(h, sig)
 }
 
+type teeHash struct {
+	h hash.Hash
+}
+
+func (t teeHash) Write(b []byte) (n int, err error) {
+	fmt.Printf("hash -> %s %+v\n", string(b), b)
+	return t.h.Write(b)
+}
+func (t teeHash) Sum(b []byte) []byte { return t.h.Sum(b) }
+func (t teeHash) Reset()              { t.h.Reset() }
+func (t teeHash) Size() int           { return t.h.Size() }
+func (t teeHash) BlockSize() int      { return t.h.BlockSize() }
+
 // userIdSignatureHash returns a Hash of the message that needs to be signed
 // to assert that pk is a valid key for id.
 func userIdSignatureHash(id string, pk *PublicKey, hashFunc crypto.Hash) (h hash.Hash, err error) {
@@ -664,6 +825,14 @@ func userIdSignatureHash(id string, pk *PublicKey, hashFunc crypto.Hash) (h hash
 	}
 	h = hashFunc.New()
 
+	updateUserIdSignatureHash(id, pk, h)
+
+	return
+}
+
+// updateUserIdSignatureHash does the actual hash updates for
+// userIdSignatureHash.
+func updateUserIdSignatureHash(id string, pk *PublicKey, h hash.Hash) {
 	// RFC 4880, section 5.2.4
 	pk.SerializeSignaturePrefix(h)
 	pk.serializeWithoutHeaders(h)
@@ -732,7 +901,9 @@ func writeMPIs(w io.Writer, mpis ...parsedMPI) (err error) {
 	return
 }
 
-// BitLength returns the bit length for the given public key.
+// BitLength returns the bit length for the given public key. Used for
+// displaying key information, actual buffers and BigInts inside may
+// have non-matching different size if the key is invalid.
 func (pk *PublicKey) BitLength() (bitLength uint16, err error) {
 	switch pk.PubKeyAlgo {
 	case PubKeyAlgoRSA, PubKeyAlgoRSAEncryptOnly, PubKeyAlgoRSASignOnly:
@@ -741,6 +912,17 @@ func (pk *PublicKey) BitLength() (bitLength uint16, err error) {
 		bitLength = pk.p.bitLength
 	case PubKeyAlgoElGamal:
 		bitLength = pk.p.bitLength
+	case PubKeyAlgoECDH:
+		ecdhPublicKey := pk.PublicKey.(*ecdh.PublicKey)
+		bitLength = uint16(ecdhPublicKey.Curve.Params().BitSize)
+	case PubKeyAlgoECDSA:
+		ecdsaPublicKey := pk.PublicKey.(*ecdsa.PublicKey)
+		bitLength = uint16(ecdsaPublicKey.Curve.Params().BitSize)
+	case PubKeyAlgoEdDSA:
+		// EdDSA only support ed25519 curves right now, just return
+		// the length. Also, we don't have any PublicKey.Curve object
+		// to look the size up from.
+		bitLength = 256
 	default:
 		err = errors.InvalidArgumentError("bad public-key algorithm")
 	}

vendor/github.com/keybase/go-crypto/openpgp/packet/public_key_v3.go

@@ -7,7 +7,6 @@ package packet
 import (
 	"crypto"
 	"crypto/md5"
-	"crypto/rsa"
 	"encoding/binary"
 	"fmt"
 	"hash"
@@ -16,7 +15,8 @@ import (
 	"strconv"
 	"time"
 
-	"golang.org/x/crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/rsa"
 )
 
 // PublicKeyV3 represents older, version 3 public keys. These keys are less secure and
@@ -42,8 +42,8 @@ func newRSAPublicKeyV3(creationTime time.Time, pub *rsa.PublicKey) *PublicKeyV3
 	pk := &PublicKeyV3{
 		CreationTime: creationTime,
 		PublicKey:    pub,
-		n:            fromBig(pub.N),
-		e:            fromBig(big.NewInt(int64(pub.E))),
+		n:            FromBig(pub.N),
+		e:            FromBig(big.NewInt(int64(pub.E))),
 	}
 
 	pk.setFingerPrintAndKeyId()
@@ -100,14 +100,14 @@ func (pk *PublicKeyV3) parseRSA(r io.Reader) (err error) {
 	if len(pk.n.bytes) < 8 {
 		return errors.StructuralError("v3 public key modulus is too short")
 	}
-	if len(pk.e.bytes) > 3 {
+	if len(pk.e.bytes) > 7 {
 		err = errors.UnsupportedError("large public exponent")
 		return
 	}
 	rsa := &rsa.PublicKey{N: new(big.Int).SetBytes(pk.n.bytes)}
 	for i := 0; i < len(pk.e.bytes); i++ {
 		rsa.E <<= 8
-		rsa.E |= int(pk.e.bytes[i])
+		rsa.E |= int64(pk.e.bytes[i])
 	}
 	pk.PublicKey = rsa
 	return
@@ -216,6 +216,7 @@ func (pk *PublicKeyV3) VerifySignatureV3(signed hash.Hash, sig *SignatureV3) (er
 		// V3 public keys only support RSA.
 		panic("shouldn't happen")
 	}
+	panic("unreachable")
 }
 
 // VerifyUserIdSignatureV3 returns nil iff sig is a valid signature, made by this

vendor/github.com/keybase/go-crypto/openpgp/packet/reader.go

@@ -5,8 +5,9 @@
 package packet
 
 import (
-	"golang.org/x/crypto/openpgp/errors"
 	"io"
+
+	"github.com/keybase/go-crypto/openpgp/errors"
 )
 
 // Reader reads packets from an io.Reader and allows packets to be 'unread' so
@@ -46,7 +47,6 @@ func (r *Reader) Next() (p Packet, err error) {
 			return nil, err
 		}
 	}
-
 	return nil, io.EOF
 }
 

vendor/github.com/keybase/go-crypto/openpgp/packet/signature.go

@@ -9,16 +9,15 @@ import (
 	"crypto"
 	"crypto/dsa"
 	"crypto/ecdsa"
-	"encoding/asn1"
 	"encoding/binary"
 	"hash"
 	"io"
-	"math/big"
 	"strconv"
 	"time"
 
-	"golang.org/x/crypto/openpgp/errors"
-	"golang.org/x/crypto/openpgp/s2k"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/s2k"
+	"github.com/keybase/go-crypto/rsa"
 )
 
 const (
@@ -29,6 +28,29 @@ const (
 	KeyFlagEncryptStorage
 )
 
+// Signer can be implemented by application code to do actual signing.
+type Signer interface {
+	hash.Hash
+	Sign(sig *Signature) error
+	KeyId() uint64
+	PublicKeyAlgo() PublicKeyAlgorithm
+}
+
+// RevocationKey represents designated revoker packet. See RFC 4880
+// section 5.2.3.15 for details.
+type RevocationKey struct {
+	Class         byte
+	PublicKeyAlgo PublicKeyAlgorithm
+	Fingerprint   []byte
+}
+
+// KeyFlagBits holds boolean whether any usage flags were provided in
+// the signature and BitField with KeyFlag* flags.
+type KeyFlagBits struct {
+	Valid    bool
+	BitField byte
+}
+
 // Signature represents a signature. See RFC 4880, section 5.2.
 type Signature struct {
 	SigType    SignatureType
@@ -45,6 +67,7 @@ type Signature struct {
 	RSASignature         parsedMPI
 	DSASigR, DSASigS     parsedMPI
 	ECDSASigR, ECDSASigS parsedMPI
+	EdDSASigR, EdDSASigS parsedMPI
 
 	// rawSubpackets contains the unparsed subpackets, in order.
 	rawSubpackets []outputSubpacket
@@ -54,8 +77,10 @@ type Signature struct {
 
 	SigLifetimeSecs, KeyLifetimeSecs                        *uint32
 	PreferredSymmetric, PreferredHash, PreferredCompression []uint8
+	PreferredKeyServer                                      string
 	IssuerKeyId                                             *uint64
 	IsPrimaryId                                             *bool
+	IssuerFingerprint                                       []byte
 
 	// FlagsValid is set if any flags were given. See RFC 4880, section
 	// 5.2.3.21 for details.
@@ -67,6 +92,12 @@ type Signature struct {
 	RevocationReason     *uint8
 	RevocationReasonText string
 
+	// PolicyURI is optional. See RFC 4880, Section 5.2.3.20 for details
+	PolicyURI string
+
+	// Regex is a regex that can match a PGP UID. See RFC 4880, 5.2.3.14 for details
+	Regex string
+
 	// MDC is set if this signature has a feature packet that indicates
 	// support for MDC subpackets.
 	MDC bool
@@ -76,6 +107,16 @@ type Signature struct {
 	// subkey as their own.
 	EmbeddedSignature *Signature
 
+	// StubbedOutCriticalError is not fail-stop, since it shouldn't break key parsing
+	// when appearing in WoT-style cross signatures. But it should prevent a signature
+	// from being applied to a primary or subkey.
+	StubbedOutCriticalError error
+
+	// DesignaterRevoker will be present if this signature certifies a
+	// designated revoking key id (3rd party key that can sign
+	// revocation for this key).
+	DesignatedRevoker *RevocationKey
+
 	outSubpackets []outputSubpacket
 }
 
@@ -98,7 +139,7 @@ func (sig *Signature) parse(r io.Reader) (err error) {
 	sig.SigType = SignatureType(buf[0])
 	sig.PubKeyAlgo = PublicKeyAlgorithm(buf[1])
 	switch sig.PubKeyAlgo {
-	case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA, PubKeyAlgoECDSA:
+	case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly, PubKeyAlgoDSA, PubKeyAlgoECDSA, PubKeyAlgoEdDSA:
 	default:
 		err = errors.UnsupportedError("public key algorithm " + strconv.Itoa(int(sig.PubKeyAlgo)))
 		return
@@ -162,6 +203,11 @@ func (sig *Signature) parse(r io.Reader) (err error) {
 		if err == nil {
 			sig.DSASigS.bytes, sig.DSASigS.bitLength, err = readMPI(r)
 		}
+	case PubKeyAlgoEdDSA:
+		sig.EdDSASigR.bytes, sig.EdDSASigR.bitLength, err = readMPI(r)
+		if err == nil {
+			sig.EdDSASigS.bytes, sig.EdDSASigS.bitLength, err = readMPI(r)
+		}
 	case PubKeyAlgoECDSA:
 		sig.ECDSASigR.bytes, sig.ECDSASigR.bitLength, err = readMPI(r)
 		if err == nil {
@@ -195,16 +241,21 @@ type signatureSubpacketType uint8
 const (
 	creationTimeSubpacket        signatureSubpacketType = 2
 	signatureExpirationSubpacket signatureSubpacketType = 3
+	regularExpressionSubpacket   signatureSubpacketType = 6
 	keyExpirationSubpacket       signatureSubpacketType = 9
 	prefSymmetricAlgosSubpacket  signatureSubpacketType = 11
+	revocationKey                signatureSubpacketType = 12
 	issuerSubpacket              signatureSubpacketType = 16
 	prefHashAlgosSubpacket       signatureSubpacketType = 21
 	prefCompressionSubpacket     signatureSubpacketType = 22
+	prefKeyServerSubpacket       signatureSubpacketType = 24
 	primaryUserIdSubpacket       signatureSubpacketType = 25
+	policyURISubpacket           signatureSubpacketType = 26
 	keyFlagsSubpacket            signatureSubpacketType = 27
 	reasonForRevocationSubpacket signatureSubpacketType = 29
 	featuresSubpacket            signatureSubpacketType = 30
 	embeddedSignatureSubpacket   signatureSubpacketType = 32
+	issuerFingerprint            signatureSubpacketType = 33
 )
 
 // parseSignatureSubpacket parses a single subpacket. len(subpacket) is >= 1.
@@ -382,6 +433,32 @@ func parseSignatureSubpacket(sig *Signature, subpacket []byte, isHashed bool) (r
 		if sigType := sig.EmbeddedSignature.SigType; sigType != SigTypePrimaryKeyBinding {
 			return nil, errors.StructuralError("cross-signature has unexpected type " + strconv.Itoa(int(sigType)))
 		}
+	case policyURISubpacket:
+		// See RFC 4880, Section 5.2.3.20
+		sig.PolicyURI = string(subpacket[:])
+	case regularExpressionSubpacket:
+		sig.Regex = string(subpacket[:])
+		if isCritical {
+			sig.StubbedOutCriticalError = errors.UnsupportedError("regex support is stubbed out")
+		}
+	case prefKeyServerSubpacket:
+		sig.PreferredKeyServer = string(subpacket[:])
+	case issuerFingerprint:
+		// The first byte is how many bytes the fingerprint is, but we'll just
+		// read until the end of the subpacket, so we'll ignore it.
+		sig.IssuerFingerprint = append([]byte{}, subpacket[1:]...)
+	case revocationKey:
+		// Authorizes the specified key to issue revocation signatures
+		// for a key.
+
+		// TODO: Class octet must have bit 0x80 set. If the bit 0x40
+		// is set, then this means that the revocation information is
+		// sensitive.
+		sig.DesignatedRevoker = &RevocationKey{
+			Class:         subpacket[0],
+			PublicKeyAlgo: PublicKeyAlgorithm(subpacket[1]),
+			Fingerprint:   append([]byte{}, subpacket[2:]...),
+		}
 	default:
 		if isCritical {
 			err = errors.UnsupportedError("unknown critical signature subpacket type " + strconv.Itoa(int(packetType)))
@@ -464,6 +541,26 @@ func (sig *Signature) KeyExpired(currentTime time.Time) bool {
 	return currentTime.After(expiry)
 }
 
+// ExpiresBeforeOther checks if other signature has expiration at
+// later date than sig.
+func (sig *Signature) ExpiresBeforeOther(other *Signature) bool {
+	if sig.KeyLifetimeSecs == nil {
+		// This sig never expires, or has infinitely long expiration
+		// time.
+		return false
+	} else if other.KeyLifetimeSecs == nil {
+		// This sig expires at some non-infinite point, but the other
+		// sig never expires.
+		return true
+	}
+
+	getExpiryDate := func(s *Signature) time.Time {
+		return s.CreationTime.Add(time.Duration(*s.KeyLifetimeSecs) * time.Second)
+	}
+
+	return getExpiryDate(other).After(getExpiryDate(sig))
+}
+
 // buildHashSuffix constructs the HashSuffix member of sig in preparation for signing.
 func (sig *Signature) buildHashSuffix() (err error) {
 	hashedSubpacketsLen := subpacketsLength(sig.outSubpackets, true)
@@ -509,16 +606,27 @@ func (sig *Signature) signPrepareHash(h hash.Hash) (digest []byte, err error) {
 // On success, the signature is stored in sig. Call Serialize to write it out.
 // If config is nil, sensible defaults will be used.
 func (sig *Signature) Sign(h hash.Hash, priv *PrivateKey, config *Config) (err error) {
+	signer, hashIsSigner := h.(Signer)
+
+	if !hashIsSigner && (priv == nil || priv.PrivateKey == nil) {
+		err = errors.InvalidArgumentError("attempting to sign with nil PrivateKey")
+		return
+	}
+
 	sig.outSubpackets = sig.buildSubpackets()
 	digest, err := sig.signPrepareHash(h)
 	if err != nil {
 		return
 	}
 
+	if hashIsSigner {
+		err = signer.Sign(sig)
+		return
+	}
+
 	switch priv.PubKeyAlgo {
 	case PubKeyAlgoRSA, PubKeyAlgoRSASignOnly:
-		// supports both *rsa.PrivateKey and crypto.Signer
-		sig.RSASignature.bytes, err = priv.PrivateKey.(crypto.Signer).Sign(config.Random(), digest, sig.Hash)
+		sig.RSASignature.bytes, err = rsa.SignPKCS1v15(config.Random(), priv.PrivateKey.(*rsa.PrivateKey), sig.Hash, digest)
 		sig.RSASignature.bitLength = uint16(8 * len(sig.RSASignature.bytes))
 	case PubKeyAlgoDSA:
 		dsaPriv := priv.PrivateKey.(*dsa.PrivateKey)
@@ -536,20 +644,16 @@ func (sig *Signature) Sign(h hash.Hash, priv *PrivateKey, config *Config) (err e
 			sig.DSASigS.bitLength = uint16(8 * len(sig.DSASigS.bytes))
 		}
 	case PubKeyAlgoECDSA:
-		var r, s *big.Int
-		if pk, ok := priv.PrivateKey.(*ecdsa.PrivateKey); ok {
-			// direct support, avoid asn1 wrapping/unwrapping
-			r, s, err = ecdsa.Sign(config.Random(), pk, digest)
-		} else {
-			var b []byte
-			b, err = priv.PrivateKey.(crypto.Signer).Sign(config.Random(), digest, nil)
-			if err == nil {
-				r, s, err = unwrapECDSASig(b)
-			}
+		r, s, err := ecdsa.Sign(config.Random(), priv.PrivateKey.(*ecdsa.PrivateKey), digest)
+		if err == nil {
+			sig.ECDSASigR = FromBig(r)
+			sig.ECDSASigS = FromBig(s)
 		}
+	case PubKeyAlgoEdDSA:
+		r, s, err := priv.PrivateKey.(*EdDSAPrivateKey).Sign(digest)
 		if err == nil {
-			sig.ECDSASigR = fromBig(r)
-			sig.ECDSASigS = fromBig(s)
+			sig.EdDSASigR = FromBytes(r)
+			sig.EdDSASigS = FromBytes(s)
 		}
 	default:
 		err = errors.UnsupportedError("public key algorithm: " + strconv.Itoa(int(sig.PubKeyAlgo)))
@@ -558,19 +662,6 @@ func (sig *Signature) Sign(h hash.Hash, priv *PrivateKey, config *Config) (err e
 	return
 }
 
-// unwrapECDSASig parses the two integer components of an ASN.1-encoded ECDSA
-// signature.
-func unwrapECDSASig(b []byte) (r, s *big.Int, err error) {
-	var ecsdaSig struct {
-		R, S *big.Int
-	}
-	_, err = asn1.Unmarshal(b, &ecsdaSig)
-	if err != nil {
-		return
-	}
-	return ecsdaSig.R, ecsdaSig.S, nil
-}
-
 // SignUserId computes a signature from priv, asserting that pub is a valid
 // key for the identity id.  On success, the signature is stored in sig. Call
 // Serialize to write it out.
@@ -583,6 +674,16 @@ func (sig *Signature) SignUserId(id string, pub *PublicKey, priv *PrivateKey, co
 	return sig.Sign(h, priv, config)
 }
 
+// SignUserIdWithSigner computes a signature from priv, asserting that pub is a
+// valid key for the identity id.  On success, the signature is stored in sig.
+// Call Serialize to write it out.
+// If config is nil, sensible defaults will be used.
+func (sig *Signature) SignUserIdWithSigner(id string, pub *PublicKey, s Signer, config *Config) error {
+	updateUserIdSignatureHash(id, pub, s)
+
+	return sig.Sign(s, nil, config)
+}
+
 // SignKey computes a signature from priv, asserting that pub is a subkey. On
 // success, the signature is stored in sig. Call Serialize to write it out.
 // If config is nil, sensible defaults will be used.
@@ -594,13 +695,25 @@ func (sig *Signature) SignKey(pub *PublicKey, priv *PrivateKey, config *Config)
 	return sig.Sign(h, priv, config)
 }
 
+// SignKeyWithSigner computes a signature using s, asserting that
+// signeePubKey is a subkey. On success, the signature is stored in sig. Call
+// Serialize to write it out. If config is nil, sensible defaults will be used.
+func (sig *Signature) SignKeyWithSigner(signeePubKey *PublicKey, signerPubKey *PublicKey, s Signer, config *Config) error {
+	updateKeySignatureHash(signerPubKey, signeePubKey, s)
+
+	return sig.Sign(s, nil, config)
+}
+
 // Serialize marshals sig to w. Sign, SignUserId or SignKey must have been
 // called first.
 func (sig *Signature) Serialize(w io.Writer) (err error) {
 	if len(sig.outSubpackets) == 0 {
 		sig.outSubpackets = sig.rawSubpackets
 	}
-	if sig.RSASignature.bytes == nil && sig.DSASigR.bytes == nil && sig.ECDSASigR.bytes == nil {
+	if sig.RSASignature.bytes == nil &&
+		sig.DSASigR.bytes == nil &&
+		sig.ECDSASigR.bytes == nil &&
+		sig.EdDSASigR.bytes == nil {
 		return errors.InvalidArgumentError("Signature: need to call Sign, SignUserId or SignKey before Serialize")
 	}
 
@@ -611,6 +724,9 @@ func (sig *Signature) Serialize(w io.Writer) (err error) {
 	case PubKeyAlgoDSA:
 		sigLength = 2 + len(sig.DSASigR.bytes)
 		sigLength += 2 + len(sig.DSASigS.bytes)
+	case PubKeyAlgoEdDSA:
+		sigLength = 2 + len(sig.EdDSASigR.bytes)
+		sigLength += 2 + len(sig.EdDSASigS.bytes)
 	case PubKeyAlgoECDSA:
 		sigLength = 2 + len(sig.ECDSASigR.bytes)
 		sigLength += 2 + len(sig.ECDSASigS.bytes)
@@ -651,6 +767,8 @@ func (sig *Signature) Serialize(w io.Writer) (err error) {
 		err = writeMPIs(w, sig.RSASignature)
 	case PubKeyAlgoDSA:
 		err = writeMPIs(w, sig.DSASigR, sig.DSASigS)
+	case PubKeyAlgoEdDSA:
+		err = writeMPIs(w, sig.EdDSASigR, sig.EdDSASigS)
 	case PubKeyAlgoECDSA:
 		err = writeMPIs(w, sig.ECDSASigR, sig.ECDSASigS)
 	default:
@@ -687,20 +805,7 @@ func (sig *Signature) buildSubpackets() (subpackets []outputSubpacket) {
 	// Key flags may only appear in self-signatures or certification signatures.
 
 	if sig.FlagsValid {
-		var flags byte
-		if sig.FlagCertify {
-			flags |= KeyFlagCertify
-		}
-		if sig.FlagSign {
-			flags |= KeyFlagSign
-		}
-		if sig.FlagEncryptCommunications {
-			flags |= KeyFlagEncryptCommunications
-		}
-		if sig.FlagEncryptStorage {
-			flags |= KeyFlagEncryptStorage
-		}
-		subpackets = append(subpackets, outputSubpacket{true, keyFlagsSubpacket, false, []byte{flags}})
+		subpackets = append(subpackets, outputSubpacket{true, keyFlagsSubpacket, false, []byte{sig.GetKeyFlags().BitField}})
 	}
 
 	// The following subpackets may only appear in self-signatures
@@ -729,3 +834,47 @@ func (sig *Signature) buildSubpackets() (subpackets []outputSubpacket) {
 
 	return
 }
+
+func (sig *Signature) GetKeyFlags() (ret KeyFlagBits) {
+	if !sig.FlagsValid {
+		return ret
+	}
+
+	ret.Valid = true
+	if sig.FlagCertify {
+		ret.BitField |= KeyFlagCertify
+	}
+	if sig.FlagSign {
+		ret.BitField |= KeyFlagSign
+	}
+	if sig.FlagEncryptCommunications {
+		ret.BitField |= KeyFlagEncryptCommunications
+	}
+	if sig.FlagEncryptStorage {
+		ret.BitField |= KeyFlagEncryptStorage
+	}
+	return ret
+}
+
+func (f *KeyFlagBits) HasFlagCertify() bool {
+	return f.BitField&KeyFlagCertify != 0
+}
+
+func (f *KeyFlagBits) HasFlagSign() bool {
+	return f.BitField&KeyFlagSign != 0
+}
+
+func (f *KeyFlagBits) HasFlagEncryptCommunications() bool {
+	return f.BitField&KeyFlagEncryptCommunications != 0
+}
+
+func (f *KeyFlagBits) HasFlagEncryptStorage() bool {
+	return f.BitField&KeyFlagEncryptStorage != 0
+}
+
+func (f *KeyFlagBits) Merge(other KeyFlagBits) {
+	if other.Valid {
+		f.Valid = true
+		f.BitField |= other.BitField
+	}
+}

vendor/github.com/keybase/go-crypto/openpgp/packet/signature_v3.go

@@ -12,8 +12,8 @@ import (
 	"strconv"
 	"time"
 
-	"golang.org/x/crypto/openpgp/errors"
-	"golang.org/x/crypto/openpgp/s2k"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/s2k"
 )
 
 // SignatureV3 represents older version 3 signatures. These signatures are less secure

vendor/github.com/keybase/go-crypto/openpgp/packet/symmetric_key_encrypted.go

@@ -10,8 +10,8 @@ import (
 	"io"
 	"strconv"
 
-	"golang.org/x/crypto/openpgp/errors"
-	"golang.org/x/crypto/openpgp/s2k"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/s2k"
 )
 
 // This is the largest session key that we'll support. Since no 512-bit cipher
@@ -48,6 +48,9 @@ func (ske *SymmetricKeyEncrypted) parse(r io.Reader) error {
 	if err != nil {
 		return err
 	}
+	if ske.s2k == nil {
+		return errors.UnsupportedError("can't use dummy S2K for symmetric key encryption")
+	}
 
 	encryptedKey := make([]byte, maxSessionKeySizeInBytes)
 	// The session key may follow. We just have to try and read to find

vendor/github.com/keybase/go-crypto/openpgp/packet/symmetrically_encrypted.go

@@ -8,10 +8,11 @@ import (
 	"crypto/cipher"
 	"crypto/sha1"
 	"crypto/subtle"
-	"golang.org/x/crypto/openpgp/errors"
 	"hash"
 	"io"
 	"strconv"
+
+	"github.com/keybase/go-crypto/openpgp/errors"
 )
 
 // SymmetricallyEncrypted represents a symmetrically encrypted byte string. The

vendor/github.com/keybase/go-crypto/openpgp/patch.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+
+patch < sig-v3.patch
+patch < s2k-gnu-dummy.patch
+find . -type f -name '*.go' -exec sed -i'' -e 's/golang.org\/x\/crypto\/openpgp/github.com\/keybase\/go-crypto\/openpgp/' {} \;
+find . -type f -name '*.go-e' -exec rm {} \;
+go test ./...

vendor/github.com/keybase/go-crypto/openpgp/read.go

@@ -3,18 +3,19 @@
 // license that can be found in the LICENSE file.
 
 // Package openpgp implements high level operations on OpenPGP messages.
-package openpgp // import "golang.org/x/crypto/openpgp"
+package openpgp // import "github.com/keybase/go-crypto/openpgp"
 
 import (
 	"crypto"
+	"crypto/hmac"
 	_ "crypto/sha256"
 	"hash"
 	"io"
 	"strconv"
 
-	"golang.org/x/crypto/openpgp/armor"
-	"golang.org/x/crypto/openpgp/errors"
-	"golang.org/x/crypto/openpgp/packet"
+	"github.com/keybase/go-crypto/openpgp/armor"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/packet"
 )
 
 // SignatureType is the armor type for a PGP signature.
@@ -50,7 +51,7 @@ type MessageDetails struct {
 	// If IsSigned is true and SignedBy is non-zero then the signature will
 	// be verified as UnverifiedBody is read. The signature cannot be
 	// checked until the whole of UnverifiedBody is read so UnverifiedBody
-	// must be consumed until EOF before the data can be trusted. Even if a
+	// must be consumed until EOF before the data can trusted. Even if a
 	// message isn't signed (or the signer is unknown) the data may contain
 	// an authentication code that is only checked once UnverifiedBody has
 	// been consumed. Once EOF has been seen, the following fields are
@@ -113,7 +114,7 @@ ParsePackets:
 			// This packet contains the decryption key encrypted to a public key.
 			md.EncryptedToKeyIds = append(md.EncryptedToKeyIds, p.KeyId)
 			switch p.Algo {
-			case packet.PubKeyAlgoRSA, packet.PubKeyAlgoRSAEncryptOnly, packet.PubKeyAlgoElGamal:
+			case packet.PubKeyAlgoRSA, packet.PubKeyAlgoRSAEncryptOnly, packet.PubKeyAlgoElGamal, packet.PubKeyAlgoECDH:
 				break
 			default:
 				continue
@@ -122,7 +123,7 @@ ParsePackets:
 			if p.KeyId == 0 {
 				keys = keyring.DecryptionKeys()
 			} else {
-				keys = keyring.KeysById(p.KeyId)
+				keys = keyring.KeysById(p.KeyId, nil)
 			}
 			for _, k := range keys {
 				pubKeys = append(pubKeys, keyEnvelopePair{k, p})
@@ -255,7 +256,7 @@ FindLiteralData:
 
 			md.IsSigned = true
 			md.SignedByKeyId = p.KeyId
-			keys := keyring.KeysByIdUsage(p.KeyId, packet.KeyFlagSign)
+			keys := keyring.KeysByIdUsage(p.KeyId, nil, packet.KeyFlagSign)
 			if len(keys) > 0 {
 				md.SignedBy = &keys[0]
 			}
@@ -336,7 +337,16 @@ func (scr *signatureCheckReader) Read(buf []byte) (n int, err error) {
 
 		var ok bool
 		if scr.md.Signature, ok = p.(*packet.Signature); ok {
-			scr.md.SignatureError = scr.md.SignedBy.PublicKey.VerifySignature(scr.h, scr.md.Signature)
+			var err error
+			if fingerprint := scr.md.Signature.IssuerFingerprint; fingerprint != nil {
+				if !hmac.Equal(fingerprint, scr.md.SignedBy.PublicKey.Fingerprint[:]) {
+					err = errors.StructuralError("bad key fingerprint")
+				}
+			}
+			if err == nil {
+				err = scr.md.SignedBy.PublicKey.VerifySignature(scr.h, scr.md.Signature)
+			}
+			scr.md.SignatureError = err
 		} else if scr.md.SignatureV3, ok = p.(*packet.SignatureV3); ok {
 			scr.md.SignatureError = scr.md.SignedBy.PublicKey.VerifySignatureV3(scr.h, scr.md.SignatureV3)
 		} else {
@@ -361,7 +371,13 @@ func (scr *signatureCheckReader) Read(buf []byte) (n int, err error) {
 // returns the signer if the signature is valid. If the signer isn't known,
 // ErrUnknownIssuer is returned.
 func CheckDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signer *Entity, err error) {
+	signer, _, err = checkDetachedSignature(keyring, signed, signature)
+	return signer, err
+}
+
+func checkDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signer *Entity, issuer *uint64, err error) {
 	var issuerKeyId uint64
+	var issuerFingerprint []byte
 	var hashFunc crypto.Hash
 	var sigType packet.SignatureType
 	var keys []Key
@@ -371,29 +387,30 @@ func CheckDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signe
 	for {
 		p, err = packets.Next()
 		if err == io.EOF {
-			return nil, errors.ErrUnknownIssuer
+			return nil, nil, errors.ErrUnknownIssuer
 		}
 		if err != nil {
-			return nil, err
+			return nil, nil, err
 		}
 
 		switch sig := p.(type) {
 		case *packet.Signature:
 			if sig.IssuerKeyId == nil {
-				return nil, errors.StructuralError("signature doesn't have an issuer")
+				return nil, nil, errors.StructuralError("signature doesn't have an issuer")
 			}
 			issuerKeyId = *sig.IssuerKeyId
 			hashFunc = sig.Hash
 			sigType = sig.SigType
+			issuerFingerprint = sig.IssuerFingerprint
 		case *packet.SignatureV3:
 			issuerKeyId = sig.IssuerKeyId
 			hashFunc = sig.Hash
 			sigType = sig.SigType
 		default:
-			return nil, errors.StructuralError("non signature packet found")
+			return nil, nil, errors.StructuralError("non signature packet found")
 		}
 
-		keys = keyring.KeysByIdUsage(issuerKeyId, packet.KeyFlagSign)
+		keys = keyring.KeysByIdUsage(issuerKeyId, issuerFingerprint, packet.KeyFlagSign)
 		if len(keys) > 0 {
 			break
 		}
@@ -405,11 +422,11 @@ func CheckDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signe
 
 	h, wrappedHash, err := hashForSignature(hashFunc, sigType)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	if _, err := io.Copy(wrappedHash, signed); err != nil && err != io.EOF {
-		return nil, err
+		return nil, nil, err
 	}
 
 	for _, key := range keys {
@@ -423,20 +440,24 @@ func CheckDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signe
 		}
 
 		if err == nil {
-			return key.Entity, nil
+			return key.Entity, &issuerKeyId, nil
 		}
 	}
 
-	return nil, err
+	return nil, nil, err
 }
 
 // CheckArmoredDetachedSignature performs the same actions as
 // CheckDetachedSignature but expects the signature to be armored.
 func CheckArmoredDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signer *Entity, err error) {
+	signer, _, err = checkArmoredDetachedSignature(keyring, signed, signature)
+	return signer, err
+}
+
+func checkArmoredDetachedSignature(keyring KeyRing, signed, signature io.Reader) (signer *Entity, issuer *uint64, err error) {
 	body, err := readArmored(signature, SignatureType)
 	if err != nil {
 		return
 	}
-
-	return CheckDetachedSignature(keyring, signed, body)
+	return checkDetachedSignature(keyring, signed, body)
 }

vendor/github.com/keybase/go-crypto/openpgp/s2k/s2k.go

@@ -4,7 +4,7 @@
 
 // Package s2k implements the various OpenPGP string-to-key transforms as
 // specified in RFC 4800 section 3.7.1.
-package s2k // import "golang.org/x/crypto/openpgp/s2k"
+package s2k // import "github.com/keybase/go-crypto/openpgp/s2k"
 
 import (
 	"crypto"
@@ -12,7 +12,7 @@ import (
 	"io"
 	"strconv"
 
-	"golang.org/x/crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/errors"
 )
 
 // Config collects configuration parameters for s2k key-stretching
@@ -151,6 +151,53 @@ func Iterated(out []byte, h hash.Hash, in []byte, salt []byte, count int) {
 	}
 }
 
+func parseGNUExtensions(r io.Reader) (f func(out, in []byte), err error) {
+	var buf [9]byte
+
+	// A three-byte string identifier
+	_, err = io.ReadFull(r, buf[:3])
+	if err != nil {
+		return
+	}
+	gnuExt := string(buf[:3])
+
+	if gnuExt != "GNU" {
+		return nil, errors.UnsupportedError("Malformed GNU extension: " + gnuExt)
+	}
+	_, err = io.ReadFull(r, buf[:1])
+	if err != nil {
+		return
+	}
+	gnuExtType := int(buf[0])
+	switch gnuExtType {
+	case 1:
+		return nil, nil
+	case 2:
+		// Read a serial number, which is prefixed by a 1-byte length.
+		// The maximum length is 16.
+		var lenBuf [1]byte
+		_, err = io.ReadFull(r, lenBuf[:])
+		if err != nil {
+			return
+		}
+
+		maxLen := 16
+		ivLen := int(lenBuf[0])
+		if ivLen > maxLen {
+			ivLen = maxLen
+		}
+		ivBuf := make([]byte, ivLen)
+		// For now we simply discard the IV
+		_, err = io.ReadFull(r, ivBuf)
+		if err != nil {
+			return
+		}
+		return nil, nil
+	default:
+		return nil, errors.UnsupportedError("unknown S2K GNU protection mode: " + strconv.Itoa(int(gnuExtType)))
+	}
+}
+
 // Parse reads a binary specification for a string-to-key transformation from r
 // and returns a function which performs that transform.
 func Parse(r io.Reader) (f func(out, in []byte), err error) {
@@ -161,6 +208,12 @@ func Parse(r io.Reader) (f func(out, in []byte), err error) {
 		return
 	}
 
+	// GNU Extensions; handle them before we try to look for a hash, which won't
+	// be needed in most cases anyway.
+	if buf[0] == 101 {
+		return parseGNUExtensions(r)
+	}
+
 	hash, ok := HashIdToHash(buf[1])
 	if !ok {
 		return nil, errors.UnsupportedError("hash for S2K function: " + strconv.Itoa(int(buf[1])))
@@ -251,7 +304,7 @@ func HashIdToHash(id byte) (h crypto.Hash, ok bool) {
 }
 
 // HashIdToString returns the name of the hash function corresponding to the
-// given OpenPGP hash id.
+// given OpenPGP hash id, or panics if id is unknown.
 func HashIdToString(id byte) (name string, ok bool) {
 	for _, m := range hashToHashIdMapping {
 		if m.id == id {

vendor/github.com/keybase/go-crypto/openpgp/sig-v3.patch

@@ -0,0 +1,135 @@
+diff --git a/openpgp/read.go b/openpgp/read.go
+index a6cecc5..0c9397b 100644
+--- a/openpgp/read.go
++++ b/openpgp/read.go
+@@ -56,8 +56,9 @@ type MessageDetails struct {
+ 	// been consumed. Once EOF has been seen, the following fields are
+ 	// valid. (An authentication code failure is reported as a
+ 	// SignatureError error when reading from UnverifiedBody.)
+-	SignatureError error             // nil if the signature is good.
+-	Signature      *packet.Signature // the signature packet itself.
++	SignatureError error               // nil if the signature is good.
++	Signature      *packet.Signature   // the signature packet itself, if v4 (default)
++	SignatureV3    *packet.SignatureV3 // the signature packet if it is a v2 or v3 signature
+ 
+ 	decrypted io.ReadCloser
+ }
+@@ -334,13 +335,15 @@ func (scr *signatureCheckReader) Read(buf []byte) (n int, err error) {
+ 		}
+ 
+ 		var ok bool
+-		if scr.md.Signature, ok = p.(*packet.Signature); !ok {
++		if scr.md.Signature, ok = p.(*packet.Signature); ok {
++			scr.md.SignatureError = scr.md.SignedBy.PublicKey.VerifySignature(scr.h, scr.md.Signature)
++		} else if scr.md.SignatureV3, ok = p.(*packet.SignatureV3); ok {
++			scr.md.SignatureError = scr.md.SignedBy.PublicKey.VerifySignatureV3(scr.h, scr.md.SignatureV3)
++		} else {
+ 			scr.md.SignatureError = errors.StructuralError("LiteralData not followed by Signature")
+ 			return
+ 		}
+ 
+-		scr.md.SignatureError = scr.md.SignedBy.PublicKey.VerifySignature(scr.h, scr.md.Signature)
+-
+ 		// The SymmetricallyEncrypted packet, if any, might have an
+ 		// unsigned hash of its own. In order to check this we need to
+ 		// close that Reader.
+diff --git a/openpgp/read_test.go b/openpgp/read_test.go
+index 52f942c..abe8d7b 100644
+--- a/openpgp/read_test.go
++++ b/openpgp/read_test.go
+@@ -13,6 +13,7 @@ import (
+ 	"strings"
+ 	"testing"
+ 
++	"golang.org/x/crypto/openpgp/armor"
+ 	"golang.org/x/crypto/openpgp/errors"
+ )
+ 
+@@ -411,6 +412,50 @@ func TestIssue11504(t *testing.T) {
+ 	testReadMessageError(t, "9303000130303030303030303030983002303030303030030000000130")
+ }
+ 
++// TestSignatureV3Message tests the verification of V3 signature, generated
++// with a modern V4-style key.  Some people have their clients set to generate
++// V3 signatures, so it's useful to be able to verify them.
++func TestSignatureV3Message(t *testing.T) {
++	sig, err := armor.Decode(strings.NewReader(signedMessageV3))
++	if err != nil {
++		t.Error(err)
++		return
++	}
++	key, err := ReadArmoredKeyRing(strings.NewReader(keyV4forVerifyingSignedMessageV3))
++	if err != nil {
++		t.Error(err)
++		return
++	}
++	md, err := ReadMessage(sig.Body, key, nil, nil)
++	if err != nil {
++		t.Error(err)
++		return
++	}
++
++	_, err = ioutil.ReadAll(md.UnverifiedBody)
++	if err != nil {
++		t.Error(err)
++		return
++	}
++
++	// We'll see a sig error here after reading in the UnverifiedBody above,
++	// if there was one to see.
++	if err = md.SignatureError; err != nil {
++		t.Error(err)
++		return
++	}
++
++	if md.SignatureV3 == nil {
++		t.Errorf("No available signature after checking signature")
++		return
++	}
++	if md.Signature != nil {
++		t.Errorf("Did not expect a signature V4 back")
++		return
++	}
++	return
++}
++
+ const testKey1KeyId = 0xA34D7E18C20C31BB
+ const testKey3KeyId = 0x338934250CCC0360
+ 
+@@ -504,3 +549,36 @@ const unknownHashFunctionHex = `8a00000040040001990006050253863c24000a09103b4fe6
+ const missingHashFunctionHex = `8a00000040040001030006050253863c24000a09103b4fe6acc0b21f32ffff0101010101010101010101010101010101010101010101010101010101010101010101010101`
+ 
+ const campbellQuine = `a0b001000300fcffa0b001000d00f2ff000300fcffa0b001000d00f2ff8270a01c00000500faff8270a01c00000500faff000500faff001400ebff8270a01c00000500faff000500faff001400ebff428821c400001400ebff428821c400001400ebff428821c400001400ebff428821c400001400ebff428821c400000000ffff000000ffff000b00f4ff428821c400000000ffff000000ffff000b00f4ff0233214c40000100feff000233214c40000100feff0000`
++
++const keyV4forVerifyingSignedMessageV3 = `-----BEGIN PGP PUBLIC KEY BLOCK-----
++Comment: GPGTools - https://gpgtools.org
++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RZia
++-----END PGP PUBLIC KEY BLOCK-----
++`
++
++const signedMessageV3 = `-----BEGIN PGP MESSAGE-----
++Comment: GPGTools - https://gpgtools.org
++
++owGbwMvMwMVYWXlhlrhb9GXG03JJDKF/MtxDMjKLFYAoUaEktbhEITe1uDgxPVWP
++q5NhKjMrWAVcC9evD8z/bF/uWNjqtk/X3y5/38XGRQHm/57rrDRYuGnTw597Xqka
++uM3137/hH3Os+Jf2dc0fXOITKwJvXJvecPVs0ta+Vg7ZO1MLn8w58Xx+6L58mbka
++DGHyU9yTueZE8D+QF/Tz28Y78dqtF56R1VPn9Xw4uJqrWYdd7b3vIZ1V6R4Nh05d
++iT57d/OhWwA=
++=hG7R
++-----END PGP MESSAGE-----
++`

vendor/github.com/keybase/go-crypto/openpgp/write.go

@@ -11,10 +11,10 @@ import (
 	"strconv"
 	"time"
 
-	"golang.org/x/crypto/openpgp/armor"
-	"golang.org/x/crypto/openpgp/errors"
-	"golang.org/x/crypto/openpgp/packet"
-	"golang.org/x/crypto/openpgp/s2k"
+	"github.com/keybase/go-crypto/openpgp/armor"
+	"github.com/keybase/go-crypto/openpgp/errors"
+	"github.com/keybase/go-crypto/openpgp/packet"
+	"github.com/keybase/go-crypto/openpgp/s2k"
 )
 
 // DetachSign signs message with the private key from signer (which must
@@ -59,20 +59,57 @@ func armoredDetachSign(w io.Writer, signer *Entity, message io.Reader, sigType p
 	return out.Close()
 }
 
+// SignWithSigner signs the message of type sigType with s and writes the
+// signature to w.
+// If config is nil, sensible defaults will be used.
+func SignWithSigner(s packet.Signer, w io.Writer, message io.Reader, sigType packet.SignatureType, config *packet.Config) (err error) {
+	keyId := s.KeyId()
+	sig := new(packet.Signature)
+	sig.SigType = sigType
+	sig.PubKeyAlgo = s.PublicKeyAlgo()
+	sig.Hash = config.Hash()
+	sig.CreationTime = config.Now()
+	sig.IssuerKeyId = &keyId
+
+	s.Reset()
+
+	wrapped := s.(hash.Hash)
+
+	if sigType == packet.SigTypeText {
+		wrapped = NewCanonicalTextHash(s)
+	}
+
+	io.Copy(wrapped, message)
+
+	err = sig.Sign(s, nil, config)
+	if err != nil {
+		return
+	}
+
+	err = sig.Serialize(w)
+
+	return
+}
+
 func detachSign(w io.Writer, signer *Entity, message io.Reader, sigType packet.SignatureType, config *packet.Config) (err error) {
-	if signer.PrivateKey == nil {
+	signerSubkey, ok := signer.signingKey(config.Now())
+	if !ok {
+		err = errors.InvalidArgumentError("no valid signing keys")
+		return
+	}
+	if signerSubkey.PrivateKey == nil {
 		return errors.InvalidArgumentError("signing key doesn't have a private key")
 	}
-	if signer.PrivateKey.Encrypted {
+	if signerSubkey.PrivateKey.Encrypted {
 		return errors.InvalidArgumentError("signing key is encrypted")
 	}
 
 	sig := new(packet.Signature)
 	sig.SigType = sigType
-	sig.PubKeyAlgo = signer.PrivateKey.PubKeyAlgo
+	sig.PubKeyAlgo = signerSubkey.PrivateKey.PubKeyAlgo
 	sig.Hash = config.Hash()
 	sig.CreationTime = config.Now()
-	sig.IssuerKeyId = &signer.PrivateKey.KeyId
+	sig.IssuerKeyId = &signerSubkey.PrivateKey.KeyId
 
 	h, wrappedHash, err := hashForSignature(sig.Hash, sig.SigType)
 	if err != nil {
@@ -80,7 +117,7 @@ func detachSign(w io.Writer, signer *Entity, message io.Reader, sigType packet.S
 	}
 	io.Copy(wrappedHash, message)
 
-	err = sig.Sign(h, signer.PrivateKey, config)
+	err = sig.Sign(h, signerSubkey.PrivateKey, config)
 	if err != nil {
 		return
 	}
@@ -198,11 +235,20 @@ func Encrypt(ciphertext io.Writer, to []*Entity, signed *Entity, hints *FileHint
 		hashToHashId(crypto.SHA1),
 		hashToHashId(crypto.RIPEMD160),
 	}
-	// In the event that a recipient doesn't specify any supported ciphers
-	// or hash functions, these are the ones that we assume that every
-	// implementation supports.
-	defaultCiphers := candidateCiphers[len(candidateCiphers)-1:]
-	defaultHashes := candidateHashes[len(candidateHashes)-1:]
+
+	// If no preferences were specified, assume something safe and reasonable.
+	defaultCiphers := []uint8{
+		uint8(packet.CipherAES128),
+		uint8(packet.CipherAES192),
+		uint8(packet.CipherAES256),
+		uint8(packet.CipherCAST5),
+	}
+
+	defaultHashes := []uint8{
+		hashToHashId(crypto.SHA256),
+		hashToHashId(crypto.SHA512),
+		hashToHashId(crypto.RIPEMD160),
+	}
 
 	encryptKeys := make([]Key, len(to))
 	for i := range to {
@@ -226,12 +272,15 @@ func Encrypt(ciphertext io.Writer, to []*Entity, signed *Entity, hints *FileHint
 		candidateHashes = intersectPreferences(candidateHashes, preferredHashes)
 	}
 
-	if len(candidateCiphers) == 0 || len(candidateHashes) == 0 {
-		return nil, errors.InvalidArgumentError("cannot encrypt because recipient set shares no common algorithms")
+	if len(candidateCiphers) == 0 {
+		return nil, errors.InvalidArgumentError("cannot encrypt because recipient set shares no common ciphers")
+	}
+	if len(candidateHashes) == 0 {
+		return nil, errors.InvalidArgumentError("cannot encrypt because recipient set shares no common hashes")
 	}
 
 	cipher := packet.CipherFunction(candidateCiphers[0])
-	// If the cipher specified by config is a candidate, we'll use that.
+	// If the cipher specifed by config is a candidate, we'll use that.
 	configuredCipher := config.Cipher()
 	for _, c := range candidateCiphers {
 		cipherFunc := packet.CipherFunction(c)
@@ -376,3 +425,71 @@ func (c noOpCloser) Write(data []byte) (n int, err error) {
 func (c noOpCloser) Close() error {
 	return nil
 }
+
+// AttachedSign is like openpgp.Encrypt (as in p.crypto/openpgp/write.go), but
+// don't encrypt at all, just sign the literal unencrypted data.
+// Unfortunately we need to duplicate some code here that's already
+// in write.go
+func AttachedSign(out io.WriteCloser, signed Entity, hints *FileHints,
+	config *packet.Config) (in io.WriteCloser, err error) {
+
+	if hints == nil {
+		hints = &FileHints{}
+	}
+
+	if config == nil {
+		config = &packet.Config{}
+	}
+
+	var signer *packet.PrivateKey
+
+	signKey, ok := signed.signingKey(config.Now())
+	if !ok {
+		err = errors.InvalidArgumentError("no valid signing keys")
+		return
+	}
+	signer = signKey.PrivateKey
+	if signer == nil {
+		err = errors.InvalidArgumentError("no valid signing keys")
+		return
+	}
+	if signer.Encrypted {
+		err = errors.InvalidArgumentError("signing key must be decrypted")
+		return
+	}
+
+	hasher := crypto.SHA512
+
+	ops := &packet.OnePassSignature{
+		SigType:    packet.SigTypeBinary,
+		Hash:       hasher,
+		PubKeyAlgo: signer.PubKeyAlgo,
+		KeyId:      signer.KeyId,
+		IsLast:     true,
+	}
+
+	if err = ops.Serialize(out); err != nil {
+		return
+	}
+
+	var epochSeconds uint32
+	if !hints.ModTime.IsZero() {
+		epochSeconds = uint32(hints.ModTime.Unix())
+	}
+
+	// We don't want the literal serializer to closer the output stream
+	// since we're going to need to write to it when we finish up the
+	// signature stuff.
+	in, err = packet.SerializeLiteral(noOpCloser{out}, hints.IsBinary, hints.FileName, epochSeconds)
+
+	if err != nil {
+		return
+	}
+
+	// If we need to write a signature packet after the literal
+	// data then we need to stop literalData from closing
+	// encryptedData.
+	in = signatureWriter{out, in, hasher, hasher.New(), signer, config}
+
+	return
+}

vendor/github.com/keybase/go-crypto/rsa/pkcs1v15.go

@@ -0,0 +1,325 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package rsa
+
+import (
+	"crypto"
+	"crypto/subtle"
+	"errors"
+	"io"
+	"math/big"
+)
+
+// This file implements encryption and decryption using PKCS#1 v1.5 padding.
+
+// PKCS1v15DecrypterOpts is for passing options to PKCS#1 v1.5 decryption using
+// the crypto.Decrypter interface.
+type PKCS1v15DecryptOptions struct {
+	// SessionKeyLen is the length of the session key that is being
+	// decrypted. If not zero, then a padding error during decryption will
+	// cause a random plaintext of this length to be returned rather than
+	// an error. These alternatives happen in constant time.
+	SessionKeyLen int
+}
+
+// EncryptPKCS1v15 encrypts the given message with RSA and the padding scheme from PKCS#1 v1.5.
+// The message must be no longer than the length of the public modulus minus 11 bytes.
+//
+// The rand parameter is used as a source of entropy to ensure that encrypting
+// the same message twice doesn't result in the same ciphertext.
+//
+// WARNING: use of this function to encrypt plaintexts other than session keys
+// is dangerous. Use RSA OAEP in new protocols.
+func EncryptPKCS1v15(rand io.Reader, pub *PublicKey, msg []byte) (out []byte, err error) {
+	if err := checkPub(pub); err != nil {
+		return nil, err
+	}
+	k := (pub.N.BitLen() + 7) / 8
+	if len(msg) > k-11 {
+		err = ErrMessageTooLong
+		return
+	}
+
+	// EM = 0x00 || 0x02 || PS || 0x00 || M
+	em := make([]byte, k)
+	em[1] = 2
+	ps, mm := em[2:len(em)-len(msg)-1], em[len(em)-len(msg):]
+	err = nonZeroRandomBytes(ps, rand)
+	if err != nil {
+		return
+	}
+	em[len(em)-len(msg)-1] = 0
+	copy(mm, msg)
+
+	m := new(big.Int).SetBytes(em)
+	c := encrypt(new(big.Int), pub, m)
+
+	copyWithLeftPad(em, c.Bytes())
+	out = em
+	return
+}
+
+// DecryptPKCS1v15 decrypts a plaintext using RSA and the padding scheme from PKCS#1 v1.5.
+// If rand != nil, it uses RSA blinding to avoid timing side-channel attacks.
+//
+// Note that whether this function returns an error or not discloses secret
+// information. If an attacker can cause this function to run repeatedly and
+// learn whether each instance returned an error then they can decrypt and
+// forge signatures as if they had the private key. See
+// DecryptPKCS1v15SessionKey for a way of solving this problem.
+func DecryptPKCS1v15(rand io.Reader, priv *PrivateKey, ciphertext []byte) (out []byte, err error) {
+	if err := checkPub(&priv.PublicKey); err != nil {
+		return nil, err
+	}
+	valid, out, index, err := decryptPKCS1v15(rand, priv, ciphertext)
+	if err != nil {
+		return
+	}
+	if valid == 0 {
+		return nil, ErrDecryption
+	}
+	out = out[index:]
+	return
+}
+
+// DecryptPKCS1v15SessionKey decrypts a session key using RSA and the padding scheme from PKCS#1 v1.5.
+// If rand != nil, it uses RSA blinding to avoid timing side-channel attacks.
+// It returns an error if the ciphertext is the wrong length or if the
+// ciphertext is greater than the public modulus. Otherwise, no error is
+// returned. If the padding is valid, the resulting plaintext message is copied
+// into key. Otherwise, key is unchanged. These alternatives occur in constant
+// time. It is intended that the user of this function generate a random
+// session key beforehand and continue the protocol with the resulting value.
+// This will remove any possibility that an attacker can learn any information
+// about the plaintext.
+// See ``Chosen Ciphertext Attacks Against Protocols Based on the RSA
+// Encryption Standard PKCS #1'', Daniel Bleichenbacher, Advances in Cryptology
+// (Crypto '98).
+//
+// Note that if the session key is too small then it may be possible for an
+// attacker to brute-force it. If they can do that then they can learn whether
+// a random value was used (because it'll be different for the same ciphertext)
+// and thus whether the padding was correct. This defeats the point of this
+// function. Using at least a 16-byte key will protect against this attack.
+func DecryptPKCS1v15SessionKey(rand io.Reader, priv *PrivateKey, ciphertext []byte, key []byte) (err error) {
+	if err := checkPub(&priv.PublicKey); err != nil {
+		return err
+	}
+	k := (priv.N.BitLen() + 7) / 8
+	if k-(len(key)+3+8) < 0 {
+		return ErrDecryption
+	}
+
+	valid, em, index, err := decryptPKCS1v15(rand, priv, ciphertext)
+	if err != nil {
+		return
+	}
+
+	if len(em) != k {
+		// This should be impossible because decryptPKCS1v15 always
+		// returns the full slice.
+		return ErrDecryption
+	}
+
+	valid &= subtle.ConstantTimeEq(int32(len(em)-index), int32(len(key)))
+	subtle.ConstantTimeCopy(valid, key, em[len(em)-len(key):])
+	return
+}
+
+// decryptPKCS1v15 decrypts ciphertext using priv and blinds the operation if
+// rand is not nil. It returns one or zero in valid that indicates whether the
+// plaintext was correctly structured. In either case, the plaintext is
+// returned in em so that it may be read independently of whether it was valid
+// in order to maintain constant memory access patterns. If the plaintext was
+// valid then index contains the index of the original message in em.
+func decryptPKCS1v15(rand io.Reader, priv *PrivateKey, ciphertext []byte) (valid int, em []byte, index int, err error) {
+	k := (priv.N.BitLen() + 7) / 8
+	if k < 11 {
+		err = ErrDecryption
+		return
+	}
+
+	c := new(big.Int).SetBytes(ciphertext)
+	m, err := decrypt(rand, priv, c)
+	if err != nil {
+		return
+	}
+
+	em = leftPad(m.Bytes(), k)
+	firstByteIsZero := subtle.ConstantTimeByteEq(em[0], 0)
+	secondByteIsTwo := subtle.ConstantTimeByteEq(em[1], 2)
+
+	// The remainder of the plaintext must be a string of non-zero random
+	// octets, followed by a 0, followed by the message.
+	//   lookingForIndex: 1 iff we are still looking for the zero.
+	//   index: the offset of the first zero byte.
+	lookingForIndex := 1
+
+	for i := 2; i < len(em); i++ {
+		equals0 := subtle.ConstantTimeByteEq(em[i], 0)
+		index = subtle.ConstantTimeSelect(lookingForIndex&equals0, i, index)
+		lookingForIndex = subtle.ConstantTimeSelect(equals0, 0, lookingForIndex)
+	}
+
+	// The PS padding must be at least 8 bytes long, and it starts two
+	// bytes into em.
+	validPS := subtle.ConstantTimeLessOrEq(2+8, index)
+
+	valid = firstByteIsZero & secondByteIsTwo & (^lookingForIndex & 1) & validPS
+	index = subtle.ConstantTimeSelect(valid, index+1, 0)
+	return valid, em, index, nil
+}
+
+// nonZeroRandomBytes fills the given slice with non-zero random octets.
+func nonZeroRandomBytes(s []byte, rand io.Reader) (err error) {
+	_, err = io.ReadFull(rand, s)
+	if err != nil {
+		return
+	}
+
+	for i := 0; i < len(s); i++ {
+		for s[i] == 0 {
+			_, err = io.ReadFull(rand, s[i:i+1])
+			if err != nil {
+				return
+			}
+			// In tests, the PRNG may return all zeros so we do
+			// this to break the loop.
+			s[i] ^= 0x42
+		}
+	}
+
+	return
+}
+
+// These are ASN1 DER structures:
+//   DigestInfo ::= SEQUENCE {
+//     digestAlgorithm AlgorithmIdentifier,
+//     digest OCTET STRING
+//   }
+// For performance, we don't use the generic ASN1 encoder. Rather, we
+// precompute a prefix of the digest value that makes a valid ASN1 DER string
+// with the correct contents.
+var hashPrefixes = map[crypto.Hash][]byte{
+	crypto.MD5:       {0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04, 0x10},
+	crypto.SHA1:      {0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03, 0x02, 0x1a, 0x05, 0x00, 0x04, 0x14},
+	crypto.SHA224:    {0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, 0x05, 0x00, 0x04, 0x1c},
+	crypto.SHA256:    {0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20},
+	crypto.SHA384:    {0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00, 0x04, 0x30},
+	crypto.SHA512:    {0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40},
+	crypto.MD5SHA1:   {}, // A special TLS case which doesn't use an ASN1 prefix.
+	crypto.RIPEMD160: {0x30, 0x20, 0x30, 0x08, 0x06, 0x06, 0x28, 0xcf, 0x06, 0x03, 0x00, 0x31, 0x04, 0x14},
+}
+
+// SignPKCS1v15 calculates the signature of hashed using RSASSA-PKCS1-V1_5-SIGN from RSA PKCS#1 v1.5.
+// Note that hashed must be the result of hashing the input message using the
+// given hash function. If hash is zero, hashed is signed directly. This isn't
+// advisable except for interoperability.
+//
+// If rand is not nil then RSA blinding will be used to avoid timing side-channel attacks.
+//
+// This function is deterministic. Thus, if the set of possible messages is
+// small, an attacker may be able to build a map from messages to signatures
+// and identify the signed messages. As ever, signatures provide authenticity,
+// not confidentiality.
+func SignPKCS1v15(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed []byte) (s []byte, err error) {
+	hashLen, prefix, err := pkcs1v15HashInfo(hash, len(hashed))
+	if err != nil {
+		return
+	}
+
+	tLen := len(prefix) + hashLen
+	k := (priv.N.BitLen() + 7) / 8
+	if k < tLen+11 {
+		return nil, ErrMessageTooLong
+	}
+
+	// EM = 0x00 || 0x01 || PS || 0x00 || T
+	em := make([]byte, k)
+	em[1] = 1
+	for i := 2; i < k-tLen-1; i++ {
+		em[i] = 0xff
+	}
+	copy(em[k-tLen:k-hashLen], prefix)
+	copy(em[k-hashLen:k], hashed)
+
+	m := new(big.Int).SetBytes(em)
+	c, err := decryptAndCheck(rand, priv, m)
+	if err != nil {
+		return
+	}
+
+	copyWithLeftPad(em, c.Bytes())
+	s = em
+	return
+}
+
+// VerifyPKCS1v15 verifies an RSA PKCS#1 v1.5 signature.
+// hashed is the result of hashing the input message using the given hash
+// function and sig is the signature. A valid signature is indicated by
+// returning a nil error. If hash is zero then hashed is used directly. This
+// isn't advisable except for interoperability.
+func VerifyPKCS1v15(pub *PublicKey, hash crypto.Hash, hashed []byte, sig []byte) (err error) {
+	hashLen, prefix, err := pkcs1v15HashInfo(hash, len(hashed))
+	if err != nil {
+		return
+	}
+
+	tLen := len(prefix) + hashLen
+	k := (pub.N.BitLen() + 7) / 8
+	if k < tLen+11 {
+		err = ErrVerification
+		return
+	}
+
+	c := new(big.Int).SetBytes(sig)
+	m := encrypt(new(big.Int), pub, c)
+	em := leftPad(m.Bytes(), k)
+	// EM = 0x00 || 0x01 || PS || 0x00 || T
+
+	ok := subtle.ConstantTimeByteEq(em[0], 0)
+	ok &= subtle.ConstantTimeByteEq(em[1], 1)
+	ok &= subtle.ConstantTimeCompare(em[k-hashLen:k], hashed)
+	ok &= subtle.ConstantTimeCompare(em[k-tLen:k-hashLen], prefix)
+	ok &= subtle.ConstantTimeByteEq(em[k-tLen-1], 0)
+
+	for i := 2; i < k-tLen-1; i++ {
+		ok &= subtle.ConstantTimeByteEq(em[i], 0xff)
+	}
+
+	if ok != 1 {
+		return ErrVerification
+	}
+
+	return nil
+}
+
+func pkcs1v15HashInfo(hash crypto.Hash, inLen int) (hashLen int, prefix []byte, err error) {
+	// Special case: crypto.Hash(0) is used to indicate that the data is
+	// signed directly.
+	if hash == 0 {
+		return inLen, nil, nil
+	}
+
+	hashLen = hash.Size()
+	if inLen != hashLen {
+		return 0, nil, errors.New("crypto/rsa: input must be hashed message")
+	}
+	prefix, ok := hashPrefixes[hash]
+	if !ok {
+		return 0, nil, errors.New("crypto/rsa: unsupported hash function")
+	}
+	return
+}
+
+// copyWithLeftPad copies src to the end of dest, padding with zero bytes as
+// needed.
+func copyWithLeftPad(dest, src []byte) {
+	numPaddingBytes := len(dest) - len(src)
+	for i := 0; i < numPaddingBytes; i++ {
+		dest[i] = 0
+	}
+	copy(dest[numPaddingBytes:], src)
+}

vendor/github.com/keybase/go-crypto/rsa/pss.go

@@ -0,0 +1,297 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package rsa
+
+// This file implements the PSS signature scheme [1].
+//
+// [1] http://www.rsa.com/rsalabs/pkcs/files/h11300-wp-pkcs-1v2-2-rsa-cryptography-standard.pdf
+
+import (
+	"bytes"
+	"crypto"
+	"errors"
+	"hash"
+	"io"
+	"math/big"
+)
+
+func emsaPSSEncode(mHash []byte, emBits int, salt []byte, hash hash.Hash) ([]byte, error) {
+	// See [1], section 9.1.1
+	hLen := hash.Size()
+	sLen := len(salt)
+	emLen := (emBits + 7) / 8
+
+	// 1.  If the length of M is greater than the input limitation for the
+	//     hash function (2^61 - 1 octets for SHA-1), output "message too
+	//     long" and stop.
+	//
+	// 2.  Let mHash = Hash(M), an octet string of length hLen.
+
+	if len(mHash) != hLen {
+		return nil, errors.New("crypto/rsa: input must be hashed message")
+	}
+
+	// 3.  If emLen < hLen + sLen + 2, output "encoding error" and stop.
+
+	if emLen < hLen+sLen+2 {
+		return nil, errors.New("crypto/rsa: encoding error")
+	}
+
+	em := make([]byte, emLen)
+	db := em[:emLen-sLen-hLen-2+1+sLen]
+	h := em[emLen-sLen-hLen-2+1+sLen : emLen-1]
+
+	// 4.  Generate a random octet string salt of length sLen; if sLen = 0,
+	//     then salt is the empty string.
+	//
+	// 5.  Let
+	//       M' = (0x)00 00 00 00 00 00 00 00 || mHash || salt;
+	//
+	//     M' is an octet string of length 8 + hLen + sLen with eight
+	//     initial zero octets.
+	//
+	// 6.  Let H = Hash(M'), an octet string of length hLen.
+
+	var prefix [8]byte
+
+	hash.Write(prefix[:])
+	hash.Write(mHash)
+	hash.Write(salt)
+
+	h = hash.Sum(h[:0])
+	hash.Reset()
+
+	// 7.  Generate an octet string PS consisting of emLen - sLen - hLen - 2
+	//     zero octets.  The length of PS may be 0.
+	//
+	// 8.  Let DB = PS || 0x01 || salt; DB is an octet string of length
+	//     emLen - hLen - 1.
+
+	db[emLen-sLen-hLen-2] = 0x01
+	copy(db[emLen-sLen-hLen-1:], salt)
+
+	// 9.  Let dbMask = MGF(H, emLen - hLen - 1).
+	//
+	// 10. Let maskedDB = DB \xor dbMask.
+
+	mgf1XOR(db, hash, h)
+
+	// 11. Set the leftmost 8 * emLen - emBits bits of the leftmost octet in
+	//     maskedDB to zero.
+
+	db[0] &= (0xFF >> uint(8*emLen-emBits))
+
+	// 12. Let EM = maskedDB || H || 0xbc.
+	em[emLen-1] = 0xBC
+
+	// 13. Output EM.
+	return em, nil
+}
+
+func emsaPSSVerify(mHash, em []byte, emBits, sLen int, hash hash.Hash) error {
+	// 1.  If the length of M is greater than the input limitation for the
+	//     hash function (2^61 - 1 octets for SHA-1), output "inconsistent"
+	//     and stop.
+	//
+	// 2.  Let mHash = Hash(M), an octet string of length hLen.
+	hLen := hash.Size()
+	if hLen != len(mHash) {
+		return ErrVerification
+	}
+
+	// 3.  If emLen < hLen + sLen + 2, output "inconsistent" and stop.
+	emLen := (emBits + 7) / 8
+	if emLen < hLen+sLen+2 {
+		return ErrVerification
+	}
+
+	// 4.  If the rightmost octet of EM does not have hexadecimal value
+	//     0xbc, output "inconsistent" and stop.
+	if em[len(em)-1] != 0xBC {
+		return ErrVerification
+	}
+
+	// 5.  Let maskedDB be the leftmost emLen - hLen - 1 octets of EM, and
+	//     let H be the next hLen octets.
+	db := em[:emLen-hLen-1]
+	h := em[emLen-hLen-1 : len(em)-1]
+
+	// 6.  If the leftmost 8 * emLen - emBits bits of the leftmost octet in
+	//     maskedDB are not all equal to zero, output "inconsistent" and
+	//     stop.
+	if em[0]&(0xFF<<uint(8-(8*emLen-emBits))) != 0 {
+		return ErrVerification
+	}
+
+	// 7.  Let dbMask = MGF(H, emLen - hLen - 1).
+	//
+	// 8.  Let DB = maskedDB \xor dbMask.
+	mgf1XOR(db, hash, h)
+
+	// 9.  Set the leftmost 8 * emLen - emBits bits of the leftmost octet in DB
+	//     to zero.
+	db[0] &= (0xFF >> uint(8*emLen-emBits))
+
+	if sLen == PSSSaltLengthAuto {
+	FindSaltLength:
+		for sLen = emLen - (hLen + 2); sLen >= 0; sLen-- {
+			switch db[emLen-hLen-sLen-2] {
+			case 1:
+				break FindSaltLength
+			case 0:
+				continue
+			default:
+				return ErrVerification
+			}
+		}
+		if sLen < 0 {
+			return ErrVerification
+		}
+	} else {
+		// 10. If the emLen - hLen - sLen - 2 leftmost octets of DB are not zero
+		//     or if the octet at position emLen - hLen - sLen - 1 (the leftmost
+		//     position is "position 1") does not have hexadecimal value 0x01,
+		//     output "inconsistent" and stop.
+		for _, e := range db[:emLen-hLen-sLen-2] {
+			if e != 0x00 {
+				return ErrVerification
+			}
+		}
+		if db[emLen-hLen-sLen-2] != 0x01 {
+			return ErrVerification
+		}
+	}
+
+	// 11.  Let salt be the last sLen octets of DB.
+	salt := db[len(db)-sLen:]
+
+	// 12.  Let
+	//          M' = (0x)00 00 00 00 00 00 00 00 || mHash || salt ;
+	//     M' is an octet string of length 8 + hLen + sLen with eight
+	//     initial zero octets.
+	//
+	// 13. Let H' = Hash(M'), an octet string of length hLen.
+	var prefix [8]byte
+	hash.Write(prefix[:])
+	hash.Write(mHash)
+	hash.Write(salt)
+
+	h0 := hash.Sum(nil)
+
+	// 14. If H = H', output "consistent." Otherwise, output "inconsistent."
+	if !bytes.Equal(h0, h) {
+		return ErrVerification
+	}
+	return nil
+}
+
+// signPSSWithSalt calculates the signature of hashed using PSS [1] with specified salt.
+// Note that hashed must be the result of hashing the input message using the
+// given hash function. salt is a random sequence of bytes whose length will be
+// later used to verify the signature.
+func signPSSWithSalt(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed, salt []byte) (s []byte, err error) {
+	nBits := priv.N.BitLen()
+	em, err := emsaPSSEncode(hashed, nBits-1, salt, hash.New())
+	if err != nil {
+		return
+	}
+	m := new(big.Int).SetBytes(em)
+	c, err := decryptAndCheck(rand, priv, m)
+	if err != nil {
+		return
+	}
+	s = make([]byte, (nBits+7)/8)
+	copyWithLeftPad(s, c.Bytes())
+	return
+}
+
+const (
+	// PSSSaltLengthAuto causes the salt in a PSS signature to be as large
+	// as possible when signing, and to be auto-detected when verifying.
+	PSSSaltLengthAuto = 0
+	// PSSSaltLengthEqualsHash causes the salt length to equal the length
+	// of the hash used in the signature.
+	PSSSaltLengthEqualsHash = -1
+)
+
+// PSSOptions contains options for creating and verifying PSS signatures.
+type PSSOptions struct {
+	// SaltLength controls the length of the salt used in the PSS
+	// signature. It can either be a number of bytes, or one of the special
+	// PSSSaltLength constants.
+	SaltLength int
+
+	// Hash, if not zero, overrides the hash function passed to SignPSS.
+	// This is the only way to specify the hash function when using the
+	// crypto.Signer interface.
+	Hash crypto.Hash
+}
+
+// HashFunc returns pssOpts.Hash so that PSSOptions implements
+// crypto.SignerOpts.
+func (pssOpts *PSSOptions) HashFunc() crypto.Hash {
+	return pssOpts.Hash
+}
+
+func (opts *PSSOptions) saltLength() int {
+	if opts == nil {
+		return PSSSaltLengthAuto
+	}
+	return opts.SaltLength
+}
+
+// SignPSS calculates the signature of hashed using RSASSA-PSS [1].
+// Note that hashed must be the result of hashing the input message using the
+// given hash function. The opts argument may be nil, in which case sensible
+// defaults are used.
+func SignPSS(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed []byte, opts *PSSOptions) (s []byte, err error) {
+	saltLength := opts.saltLength()
+	switch saltLength {
+	case PSSSaltLengthAuto:
+		saltLength = (priv.N.BitLen()+7)/8 - 2 - hash.Size()
+	case PSSSaltLengthEqualsHash:
+		saltLength = hash.Size()
+	}
+
+	if opts != nil && opts.Hash != 0 {
+		hash = opts.Hash
+	}
+
+	salt := make([]byte, saltLength)
+	if _, err = io.ReadFull(rand, salt); err != nil {
+		return
+	}
+	return signPSSWithSalt(rand, priv, hash, hashed, salt)
+}
+
+// VerifyPSS verifies a PSS signature.
+// hashed is the result of hashing the input message using the given hash
+// function and sig is the signature. A valid signature is indicated by
+// returning a nil error. The opts argument may be nil, in which case sensible
+// defaults are used.
+func VerifyPSS(pub *PublicKey, hash crypto.Hash, hashed []byte, sig []byte, opts *PSSOptions) error {
+	return verifyPSS(pub, hash, hashed, sig, opts.saltLength())
+}
+
+// verifyPSS verifies a PSS signature with the given salt length.
+func verifyPSS(pub *PublicKey, hash crypto.Hash, hashed []byte, sig []byte, saltLen int) error {
+	nBits := pub.N.BitLen()
+	if len(sig) != (nBits+7)/8 {
+		return ErrVerification
+	}
+	s := new(big.Int).SetBytes(sig)
+	m := encrypt(new(big.Int), pub, s)
+	emBits := nBits - 1
+	emLen := (emBits + 7) / 8
+	if emLen < len(m.Bytes()) {
+		return ErrVerification
+	}
+	em := make([]byte, emLen)
+	copyWithLeftPad(em, m.Bytes())
+	if saltLen == PSSSaltLengthEqualsHash {
+		saltLen = hash.Size()
+	}
+	return emsaPSSVerify(hashed, em, emBits, saltLen, hash.New())
+}

vendor/github.com/keybase/go-crypto/rsa/rsa.go

@@ -0,0 +1,646 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package rsa implements RSA encryption as specified in PKCS#1.
+//
+// RSA is a single, fundamental operation that is used in this package to
+// implement either public-key encryption or public-key signatures.
+//
+// The original specification for encryption and signatures with RSA is PKCS#1
+// and the terms "RSA encryption" and "RSA signatures" by default refer to
+// PKCS#1 version 1.5. However, that specification has flaws and new designs
+// should use version two, usually called by just OAEP and PSS, where
+// possible.
+//
+// Two sets of interfaces are included in this package. When a more abstract
+// interface isn't neccessary, there are functions for encrypting/decrypting
+// with v1.5/OAEP and signing/verifying with v1.5/PSS. If one needs to abstract
+// over the public-key primitive, the PrivateKey struct implements the
+// Decrypter and Signer interfaces from the crypto package.
+package rsa
+
+import (
+	"crypto"
+	"crypto/rand"
+	"crypto/subtle"
+	"errors"
+	"hash"
+	"io"
+	"math/big"
+)
+
+var bigZero = big.NewInt(0)
+var bigOne = big.NewInt(1)
+
+// A PublicKey represents the public part of an RSA key.
+type PublicKey struct {
+	N *big.Int // modulus
+	E int64    // public exponent
+}
+
+// OAEPOptions is an interface for passing options to OAEP decryption using the
+// crypto.Decrypter interface.
+type OAEPOptions struct {
+	// Hash is the hash function that will be used when generating the mask.
+	Hash crypto.Hash
+	// Label is an arbitrary byte string that must be equal to the value
+	// used when encrypting.
+	Label []byte
+}
+
+var (
+	errPublicModulus       = errors.New("crypto/rsa: missing public modulus")
+	errPublicExponentSmall = errors.New("crypto/rsa: public exponent too small")
+	errPublicExponentLarge = errors.New("crypto/rsa: public exponent too large")
+)
+
+// checkPub sanity checks the public key before we use it.
+// We require pub.E to fit into a 32-bit integer so that we
+// do not have different behavior depending on whether
+// int is 32 or 64 bits. See also
+// http://www.imperialviolet.org/2012/03/16/rsae.html.
+func checkPub(pub *PublicKey) error {
+	if pub.N == nil {
+		return errPublicModulus
+	}
+	if pub.E < 2 {
+		return errPublicExponentSmall
+	}
+	if pub.E > 1<<63-1 {
+		return errPublicExponentLarge
+	}
+	return nil
+}
+
+// A PrivateKey represents an RSA key
+type PrivateKey struct {
+	PublicKey            // public part.
+	D         *big.Int   // private exponent
+	Primes    []*big.Int // prime factors of N, has >= 2 elements.
+
+	// Precomputed contains precomputed values that speed up private
+	// operations, if available.
+	Precomputed PrecomputedValues
+}
+
+// Public returns the public key corresponding to priv.
+func (priv *PrivateKey) Public() crypto.PublicKey {
+	return &priv.PublicKey
+}
+
+// Sign signs msg with priv, reading randomness from rand. If opts is a
+// *PSSOptions then the PSS algorithm will be used, otherwise PKCS#1 v1.5 will
+// be used. This method is intended to support keys where the private part is
+// kept in, for example, a hardware module. Common uses should use the Sign*
+// functions in this package.
+func (priv *PrivateKey) Sign(rand io.Reader, msg []byte, opts crypto.SignerOpts) ([]byte, error) {
+	if pssOpts, ok := opts.(*PSSOptions); ok {
+		return SignPSS(rand, priv, pssOpts.Hash, msg, pssOpts)
+	}
+
+	return SignPKCS1v15(rand, priv, opts.HashFunc(), msg)
+}
+
+// Decrypt decrypts ciphertext with priv. If opts is nil or of type
+// *PKCS1v15DecryptOptions then PKCS#1 v1.5 decryption is performed. Otherwise
+// opts must have type *OAEPOptions and OAEP decryption is done.
+func (priv *PrivateKey) Decrypt(rand io.Reader, ciphertext []byte, opts crypto.DecrypterOpts) (plaintext []byte, err error) {
+	if opts == nil {
+		return DecryptPKCS1v15(rand, priv, ciphertext)
+	}
+
+	switch opts := opts.(type) {
+	case *OAEPOptions:
+		return DecryptOAEP(opts.Hash.New(), rand, priv, ciphertext, opts.Label)
+
+	case *PKCS1v15DecryptOptions:
+		if l := opts.SessionKeyLen; l > 0 {
+			plaintext = make([]byte, l)
+			if _, err := io.ReadFull(rand, plaintext); err != nil {
+				return nil, err
+			}
+			if err := DecryptPKCS1v15SessionKey(rand, priv, ciphertext, plaintext); err != nil {
+				return nil, err
+			}
+			return plaintext, nil
+		} else {
+			return DecryptPKCS1v15(rand, priv, ciphertext)
+		}
+
+	default:
+		return nil, errors.New("crypto/rsa: invalid options for Decrypt")
+	}
+}
+
+type PrecomputedValues struct {
+	Dp, Dq *big.Int // D mod (P-1) (or mod Q-1)
+	Qinv   *big.Int // Q^-1 mod P
+
+	// CRTValues is used for the 3rd and subsequent primes. Due to a
+	// historical accident, the CRT for the first two primes is handled
+	// differently in PKCS#1 and interoperability is sufficiently
+	// important that we mirror this.
+	CRTValues []CRTValue
+}
+
+// CRTValue contains the precomputed Chinese remainder theorem values.
+type CRTValue struct {
+	Exp   *big.Int // D mod (prime-1).
+	Coeff *big.Int // R·Coeff ≡ 1 mod Prime.
+	R     *big.Int // product of primes prior to this (inc p and q).
+}
+
+// Validate performs basic sanity checks on the key.
+// It returns nil if the key is valid, or else an error describing a problem.
+func (priv *PrivateKey) Validate() error {
+	if err := checkPub(&priv.PublicKey); err != nil {
+		return err
+	}
+
+	// Check that Πprimes == n.
+	modulus := new(big.Int).Set(bigOne)
+	for _, prime := range priv.Primes {
+		// Any primes ≤ 1 will cause divide-by-zero panics later.
+		if prime.Cmp(bigOne) <= 0 {
+			return errors.New("crypto/rsa: invalid prime value")
+		}
+		modulus.Mul(modulus, prime)
+	}
+	if modulus.Cmp(priv.N) != 0 {
+		return errors.New("crypto/rsa: invalid modulus")
+	}
+
+	// Check that de ≡ 1 mod p-1, for each prime.
+	// This implies that e is coprime to each p-1 as e has a multiplicative
+	// inverse. Therefore e is coprime to lcm(p-1,q-1,r-1,...) =
+	// exponent(ℤ/nℤ). It also implies that a^de ≡ a mod p as a^(p-1) ≡ 1
+	// mod p. Thus a^de ≡ a mod n for all a coprime to n, as required.
+	congruence := new(big.Int)
+	de := new(big.Int).SetInt64(int64(priv.E))
+	de.Mul(de, priv.D)
+	for _, prime := range priv.Primes {
+		pminus1 := new(big.Int).Sub(prime, bigOne)
+		congruence.Mod(de, pminus1)
+		if congruence.Cmp(bigOne) != 0 {
+			return errors.New("crypto/rsa: invalid exponents")
+		}
+	}
+	return nil
+}
+
+// GenerateKey generates an RSA keypair of the given bit size using the
+// random source random (for example, crypto/rand.Reader).
+func GenerateKey(random io.Reader, bits int) (priv *PrivateKey, err error) {
+	return GenerateMultiPrimeKey(random, 2, bits)
+}
+
+// GenerateMultiPrimeKey generates a multi-prime RSA keypair of the given bit
+// size and the given random source, as suggested in [1]. Although the public
+// keys are compatible (actually, indistinguishable) from the 2-prime case,
+// the private keys are not. Thus it may not be possible to export multi-prime
+// private keys in certain formats or to subsequently import them into other
+// code.
+//
+// Table 1 in [2] suggests maximum numbers of primes for a given size.
+//
+// [1] US patent 4405829 (1972, expired)
+// [2] http://www.cacr.math.uwaterloo.ca/techreports/2006/cacr2006-16.pdf
+func GenerateMultiPrimeKey(random io.Reader, nprimes int, bits int) (priv *PrivateKey, err error) {
+	priv = new(PrivateKey)
+	priv.E = 65537
+
+	if nprimes < 2 {
+		return nil, errors.New("crypto/rsa: GenerateMultiPrimeKey: nprimes must be >= 2")
+	}
+
+	primes := make([]*big.Int, nprimes)
+
+NextSetOfPrimes:
+	for {
+		todo := bits
+		// crypto/rand should set the top two bits in each prime.
+		// Thus each prime has the form
+		//   p_i = 2^bitlen(p_i) × 0.11... (in base 2).
+		// And the product is:
+		//   P = 2^todo × α
+		// where α is the product of nprimes numbers of the form 0.11...
+		//
+		// If α < 1/2 (which can happen for nprimes > 2), we need to
+		// shift todo to compensate for lost bits: the mean value of 0.11...
+		// is 7/8, so todo + shift - nprimes * log2(7/8) ~= bits - 1/2
+		// will give good results.
+		if nprimes >= 7 {
+			todo += (nprimes - 2) / 5
+		}
+		for i := 0; i < nprimes; i++ {
+			primes[i], err = rand.Prime(random, todo/(nprimes-i))
+			if err != nil {
+				return nil, err
+			}
+			todo -= primes[i].BitLen()
+		}
+
+		// Make sure that primes is pairwise unequal.
+		for i, prime := range primes {
+			for j := 0; j < i; j++ {
+				if prime.Cmp(primes[j]) == 0 {
+					continue NextSetOfPrimes
+				}
+			}
+		}
+
+		n := new(big.Int).Set(bigOne)
+		totient := new(big.Int).Set(bigOne)
+		pminus1 := new(big.Int)
+		for _, prime := range primes {
+			n.Mul(n, prime)
+			pminus1.Sub(prime, bigOne)
+			totient.Mul(totient, pminus1)
+		}
+		if n.BitLen() != bits {
+			// This should never happen for nprimes == 2 because
+			// crypto/rand should set the top two bits in each prime.
+			// For nprimes > 2 we hope it does not happen often.
+			continue NextSetOfPrimes
+		}
+
+		g := new(big.Int)
+		priv.D = new(big.Int)
+		y := new(big.Int)
+		e := big.NewInt(int64(priv.E))
+		g.GCD(priv.D, y, e, totient)
+
+		if g.Cmp(bigOne) == 0 {
+			if priv.D.Sign() < 0 {
+				priv.D.Add(priv.D, totient)
+			}
+			priv.Primes = primes
+			priv.N = n
+
+			break
+		}
+	}
+
+	priv.Precompute()
+	return
+}
+
+// incCounter increments a four byte, big-endian counter.
+func incCounter(c *[4]byte) {
+	if c[3]++; c[3] != 0 {
+		return
+	}
+	if c[2]++; c[2] != 0 {
+		return
+	}
+	if c[1]++; c[1] != 0 {
+		return
+	}
+	c[0]++
+}
+
+// mgf1XOR XORs the bytes in out with a mask generated using the MGF1 function
+// specified in PKCS#1 v2.1.
+func mgf1XOR(out []byte, hash hash.Hash, seed []byte) {
+	var counter [4]byte
+	var digest []byte
+
+	done := 0
+	for done < len(out) {
+		hash.Write(seed)
+		hash.Write(counter[0:4])
+		digest = hash.Sum(digest[:0])
+		hash.Reset()
+
+		for i := 0; i < len(digest) && done < len(out); i++ {
+			out[done] ^= digest[i]
+			done++
+		}
+		incCounter(&counter)
+	}
+}
+
+// ErrMessageTooLong is returned when attempting to encrypt a message which is
+// too large for the size of the public key.
+var ErrMessageTooLong = errors.New("crypto/rsa: message too long for RSA public key size")
+
+func encrypt(c *big.Int, pub *PublicKey, m *big.Int) *big.Int {
+	e := big.NewInt(int64(pub.E))
+	c.Exp(m, e, pub.N)
+	return c
+}
+
+// EncryptOAEP encrypts the given message with RSA-OAEP.
+//
+// OAEP is parameterised by a hash function that is used as a random oracle.
+// Encryption and decryption of a given message must use the same hash function
+// and sha256.New() is a reasonable choice.
+//
+// The random parameter is used as a source of entropy to ensure that
+// encrypting the same message twice doesn't result in the same ciphertext.
+//
+// The label parameter may contain arbitrary data that will not be encrypted,
+// but which gives important context to the message. For example, if a given
+// public key is used to decrypt two types of messages then distinct label
+// values could be used to ensure that a ciphertext for one purpose cannot be
+// used for another by an attacker. If not required it can be empty.
+//
+// The message must be no longer than the length of the public modulus less
+// twice the hash length plus 2.
+func EncryptOAEP(hash hash.Hash, random io.Reader, pub *PublicKey, msg []byte, label []byte) (out []byte, err error) {
+	if err := checkPub(pub); err != nil {
+		return nil, err
+	}
+	hash.Reset()
+	k := (pub.N.BitLen() + 7) / 8
+	if len(msg) > k-2*hash.Size()-2 {
+		err = ErrMessageTooLong
+		return
+	}
+
+	hash.Write(label)
+	lHash := hash.Sum(nil)
+	hash.Reset()
+
+	em := make([]byte, k)
+	seed := em[1 : 1+hash.Size()]
+	db := em[1+hash.Size():]
+
+	copy(db[0:hash.Size()], lHash)
+	db[len(db)-len(msg)-1] = 1
+	copy(db[len(db)-len(msg):], msg)
+
+	_, err = io.ReadFull(random, seed)
+	if err != nil {
+		return
+	}
+
+	mgf1XOR(db, hash, seed)
+	mgf1XOR(seed, hash, db)
+
+	m := new(big.Int)
+	m.SetBytes(em)
+	c := encrypt(new(big.Int), pub, m)
+	out = c.Bytes()
+
+	if len(out) < k {
+		// If the output is too small, we need to left-pad with zeros.
+		t := make([]byte, k)
+		copy(t[k-len(out):], out)
+		out = t
+	}
+
+	return
+}
+
+// ErrDecryption represents a failure to decrypt a message.
+// It is deliberately vague to avoid adaptive attacks.
+var ErrDecryption = errors.New("crypto/rsa: decryption error")
+
+// ErrVerification represents a failure to verify a signature.
+// It is deliberately vague to avoid adaptive attacks.
+var ErrVerification = errors.New("crypto/rsa: verification error")
+
+// modInverse returns ia, the inverse of a in the multiplicative group of prime
+// order n. It requires that a be a member of the group (i.e. less than n).
+func modInverse(a, n *big.Int) (ia *big.Int, ok bool) {
+	g := new(big.Int)
+	x := new(big.Int)
+	y := new(big.Int)
+	g.GCD(x, y, a, n)
+	if g.Cmp(bigOne) != 0 {
+		// In this case, a and n aren't coprime and we cannot calculate
+		// the inverse. This happens because the values of n are nearly
+		// prime (being the product of two primes) rather than truly
+		// prime.
+		return
+	}
+
+	if x.Cmp(bigOne) < 0 {
+		// 0 is not the multiplicative inverse of any element so, if x
+		// < 1, then x is negative.
+		x.Add(x, n)
+	}
+
+	return x, true
+}
+
+// Precompute performs some calculations that speed up private key operations
+// in the future.
+func (priv *PrivateKey) Precompute() {
+	if priv.Precomputed.Dp != nil {
+		return
+	}
+
+	priv.Precomputed.Dp = new(big.Int).Sub(priv.Primes[0], bigOne)
+	priv.Precomputed.Dp.Mod(priv.D, priv.Precomputed.Dp)
+
+	priv.Precomputed.Dq = new(big.Int).Sub(priv.Primes[1], bigOne)
+	priv.Precomputed.Dq.Mod(priv.D, priv.Precomputed.Dq)
+
+	priv.Precomputed.Qinv = new(big.Int).ModInverse(priv.Primes[1], priv.Primes[0])
+
+	r := new(big.Int).Mul(priv.Primes[0], priv.Primes[1])
+	priv.Precomputed.CRTValues = make([]CRTValue, len(priv.Primes)-2)
+	for i := 2; i < len(priv.Primes); i++ {
+		prime := priv.Primes[i]
+		values := &priv.Precomputed.CRTValues[i-2]
+
+		values.Exp = new(big.Int).Sub(prime, bigOne)
+		values.Exp.Mod(priv.D, values.Exp)
+
+		values.R = new(big.Int).Set(r)
+		values.Coeff = new(big.Int).ModInverse(r, prime)
+
+		r.Mul(r, prime)
+	}
+}
+
+// decrypt performs an RSA decryption, resulting in a plaintext integer. If a
+// random source is given, RSA blinding is used.
+func decrypt(random io.Reader, priv *PrivateKey, c *big.Int) (m *big.Int, err error) {
+	// TODO(agl): can we get away with reusing blinds?
+	if c.Cmp(priv.N) > 0 {
+		err = ErrDecryption
+		return
+	}
+
+	var ir *big.Int
+	if random != nil {
+		// Blinding enabled. Blinding involves multiplying c by r^e.
+		// Then the decryption operation performs (m^e * r^e)^d mod n
+		// which equals mr mod n. The factor of r can then be removed
+		// by multiplying by the multiplicative inverse of r.
+
+		var r *big.Int
+
+		for {
+			r, err = rand.Int(random, priv.N)
+			if err != nil {
+				return
+			}
+			if r.Cmp(bigZero) == 0 {
+				r = bigOne
+			}
+			var ok bool
+			ir, ok = modInverse(r, priv.N)
+			if ok {
+				break
+			}
+		}
+		bigE := big.NewInt(int64(priv.E))
+		rpowe := new(big.Int).Exp(r, bigE, priv.N)
+		cCopy := new(big.Int).Set(c)
+		cCopy.Mul(cCopy, rpowe)
+		cCopy.Mod(cCopy, priv.N)
+		c = cCopy
+	}
+
+	if priv.Precomputed.Dp == nil {
+		m = new(big.Int).Exp(c, priv.D, priv.N)
+	} else {
+		// We have the precalculated values needed for the CRT.
+		m = new(big.Int).Exp(c, priv.Precomputed.Dp, priv.Primes[0])
+		m2 := new(big.Int).Exp(c, priv.Precomputed.Dq, priv.Primes[1])
+		m.Sub(m, m2)
+		if m.Sign() < 0 {
+			m.Add(m, priv.Primes[0])
+		}
+		m.Mul(m, priv.Precomputed.Qinv)
+		m.Mod(m, priv.Primes[0])
+		m.Mul(m, priv.Primes[1])
+		m.Add(m, m2)
+
+		for i, values := range priv.Precomputed.CRTValues {
+			prime := priv.Primes[2+i]
+			m2.Exp(c, values.Exp, prime)
+			m2.Sub(m2, m)
+			m2.Mul(m2, values.Coeff)
+			m2.Mod(m2, prime)
+			if m2.Sign() < 0 {
+				m2.Add(m2, prime)
+			}
+			m2.Mul(m2, values.R)
+			m.Add(m, m2)
+		}
+	}
+
+	if ir != nil {
+		// Unblind.
+		m.Mul(m, ir)
+		m.Mod(m, priv.N)
+	}
+
+	return
+}
+
+func decryptAndCheck(random io.Reader, priv *PrivateKey, c *big.Int) (m *big.Int, err error) {
+	m, err = decrypt(random, priv, c)
+	if err != nil {
+		return nil, err
+	}
+
+	// In order to defend against errors in the CRT computation, m^e is
+	// calculated, which should match the original ciphertext.
+	check := encrypt(new(big.Int), &priv.PublicKey, m)
+	if c.Cmp(check) != 0 {
+		return nil, errors.New("rsa: internal error")
+	}
+	return m, nil
+}
+
+// DecryptOAEP decrypts ciphertext using RSA-OAEP.
+
+// OAEP is parameterised by a hash function that is used as a random oracle.
+// Encryption and decryption of a given message must use the same hash function
+// and sha256.New() is a reasonable choice.
+//
+// The random parameter, if not nil, is used to blind the private-key operation
+// and avoid timing side-channel attacks. Blinding is purely internal to this
+// function – the random data need not match that used when encrypting.
+//
+// The label parameter must match the value given when encrypting. See
+// EncryptOAEP for details.
+func DecryptOAEP(hash hash.Hash, random io.Reader, priv *PrivateKey, ciphertext []byte, label []byte) (msg []byte, err error) {
+	if err := checkPub(&priv.PublicKey); err != nil {
+		return nil, err
+	}
+	k := (priv.N.BitLen() + 7) / 8
+	if len(ciphertext) > k ||
+		k < hash.Size()*2+2 {
+		err = ErrDecryption
+		return
+	}
+
+	c := new(big.Int).SetBytes(ciphertext)
+
+	m, err := decrypt(random, priv, c)
+	if err != nil {
+		return
+	}
+
+	hash.Write(label)
+	lHash := hash.Sum(nil)
+	hash.Reset()
+
+	// Converting the plaintext number to bytes will strip any
+	// leading zeros so we may have to left pad. We do this unconditionally
+	// to avoid leaking timing information. (Although we still probably
+	// leak the number of leading zeros. It's not clear that we can do
+	// anything about this.)
+	em := leftPad(m.Bytes(), k)
+
+	firstByteIsZero := subtle.ConstantTimeByteEq(em[0], 0)
+
+	seed := em[1 : hash.Size()+1]
+	db := em[hash.Size()+1:]
+
+	mgf1XOR(seed, hash, db)
+	mgf1XOR(db, hash, seed)
+
+	lHash2 := db[0:hash.Size()]
+
+	// We have to validate the plaintext in constant time in order to avoid
+	// attacks like: J. Manger. A Chosen Ciphertext Attack on RSA Optimal
+	// Asymmetric Encryption Padding (OAEP) as Standardized in PKCS #1
+	// v2.0. In J. Kilian, editor, Advances in Cryptology.
+	lHash2Good := subtle.ConstantTimeCompare(lHash, lHash2)
+
+	// The remainder of the plaintext must be zero or more 0x00, followed
+	// by 0x01, followed by the message.
+	//   lookingForIndex: 1 iff we are still looking for the 0x01
+	//   index: the offset of the first 0x01 byte
+	//   invalid: 1 iff we saw a non-zero byte before the 0x01.
+	var lookingForIndex, index, invalid int
+	lookingForIndex = 1
+	rest := db[hash.Size():]
+
+	for i := 0; i < len(rest); i++ {
+		equals0 := subtle.ConstantTimeByteEq(rest[i], 0)
+		equals1 := subtle.ConstantTimeByteEq(rest[i], 1)
+		index = subtle.ConstantTimeSelect(lookingForIndex&equals1, i, index)
+		lookingForIndex = subtle.ConstantTimeSelect(equals1, 0, lookingForIndex)
+		invalid = subtle.ConstantTimeSelect(lookingForIndex&^equals0, 1, invalid)
+	}
+
+	if firstByteIsZero&lHash2Good&^invalid&^lookingForIndex != 1 {
+		err = ErrDecryption
+		return
+	}
+
+	msg = rest[index+1:]
+	return
+}
+
+// leftPad returns a new slice of length size. The contents of input are right
+// aligned in the new slice.
+func leftPad(input []byte, size int) (out []byte) {
+	n := len(input)
+	if n > size {
+		n = size
+	}
+	out = make([]byte, size)
+	copy(out[len(out)-n:], input)
+	return
+}

vendor/golang.org/x/crypto/openpgp/keys.go

@@ -1,637 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package openpgp
-
-import (
-	"crypto/rsa"
-	"io"
-	"time"
-
-	"golang.org/x/crypto/openpgp/armor"
-	"golang.org/x/crypto/openpgp/errors"
-	"golang.org/x/crypto/openpgp/packet"
-)
-
-// PublicKeyType is the armor type for a PGP public key.
-var PublicKeyType = "PGP PUBLIC KEY BLOCK"
-
-// PrivateKeyType is the armor type for a PGP private key.
-var PrivateKeyType = "PGP PRIVATE KEY BLOCK"
-
-// An Entity represents the components of an OpenPGP key: a primary public key
-// (which must be a signing key), one or more identities claimed by that key,
-// and zero or more subkeys, which may be encryption keys.
-type Entity struct {
-	PrimaryKey  *packet.PublicKey
-	PrivateKey  *packet.PrivateKey
-	Identities  map[string]*Identity // indexed by Identity.Name
-	Revocations []*packet.Signature
-	Subkeys     []Subkey
-}
-
-// An Identity represents an identity claimed by an Entity and zero or more
-// assertions by other entities about that claim.
-type Identity struct {
-	Name          string // by convention, has the form "Full Name (comment) <email@example.com>"
-	UserId        *packet.UserId
-	SelfSignature *packet.Signature
-	Signatures    []*packet.Signature
-}
-
-// A Subkey is an additional public key in an Entity. Subkeys can be used for
-// encryption.
-type Subkey struct {
-	PublicKey  *packet.PublicKey
-	PrivateKey *packet.PrivateKey
-	Sig        *packet.Signature
-}
-
-// A Key identifies a specific public key in an Entity. This is either the
-// Entity's primary key or a subkey.
-type Key struct {
-	Entity        *Entity
-	PublicKey     *packet.PublicKey
-	PrivateKey    *packet.PrivateKey
-	SelfSignature *packet.Signature
-}
-
-// A KeyRing provides access to public and private keys.
-type KeyRing interface {
-	// KeysById returns the set of keys that have the given key id.
-	KeysById(id uint64) []Key
-	// KeysByIdAndUsage returns the set of keys with the given id
-	// that also meet the key usage given by requiredUsage.
-	// The requiredUsage is expressed as the bitwise-OR of
-	// packet.KeyFlag* values.
-	KeysByIdUsage(id uint64, requiredUsage byte) []Key
-	// DecryptionKeys returns all private keys that are valid for
-	// decryption.
-	DecryptionKeys() []Key
-}
-
-// primaryIdentity returns the Identity marked as primary or the first identity
-// if none are so marked.
-func (e *Entity) primaryIdentity() *Identity {
-	var firstIdentity *Identity
-	for _, ident := range e.Identities {
-		if firstIdentity == nil {
-			firstIdentity = ident
-		}
-		if ident.SelfSignature.IsPrimaryId != nil && *ident.SelfSignature.IsPrimaryId {
-			return ident
-		}
-	}
-	return firstIdentity
-}
-
-// encryptionKey returns the best candidate Key for encrypting a message to the
-// given Entity.
-func (e *Entity) encryptionKey(now time.Time) (Key, bool) {
-	candidateSubkey := -1
-
-	// Iterate the keys to find the newest key
-	var maxTime time.Time
-	for i, subkey := range e.Subkeys {
-		if subkey.Sig.FlagsValid &&
-			subkey.Sig.FlagEncryptCommunications &&
-			subkey.PublicKey.PubKeyAlgo.CanEncrypt() &&
-			!subkey.Sig.KeyExpired(now) &&
-			(maxTime.IsZero() || subkey.Sig.CreationTime.After(maxTime)) {
-			candidateSubkey = i
-			maxTime = subkey.Sig.CreationTime
-		}
-	}
-
-	if candidateSubkey != -1 {
-		subkey := e.Subkeys[candidateSubkey]
-		return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig}, true
-	}
-
-	// If we don't have any candidate subkeys for encryption and
-	// the primary key doesn't have any usage metadata then we
-	// assume that the primary key is ok. Or, if the primary key is
-	// marked as ok to encrypt to, then we can obviously use it.
-	i := e.primaryIdentity()
-	if !i.SelfSignature.FlagsValid || i.SelfSignature.FlagEncryptCommunications &&
-		e.PrimaryKey.PubKeyAlgo.CanEncrypt() &&
-		!i.SelfSignature.KeyExpired(now) {
-		return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature}, true
-	}
-
-	// This Entity appears to be signing only.
-	return Key{}, false
-}
-
-// signingKey return the best candidate Key for signing a message with this
-// Entity.
-func (e *Entity) signingKey(now time.Time) (Key, bool) {
-	candidateSubkey := -1
-
-	for i, subkey := range e.Subkeys {
-		if subkey.Sig.FlagsValid &&
-			subkey.Sig.FlagSign &&
-			subkey.PublicKey.PubKeyAlgo.CanSign() &&
-			!subkey.Sig.KeyExpired(now) {
-			candidateSubkey = i
-			break
-		}
-	}
-
-	if candidateSubkey != -1 {
-		subkey := e.Subkeys[candidateSubkey]
-		return Key{e, subkey.PublicKey, subkey.PrivateKey, subkey.Sig}, true
-	}
-
-	// If we have no candidate subkey then we assume that it's ok to sign
-	// with the primary key.
-	i := e.primaryIdentity()
-	if !i.SelfSignature.FlagsValid || i.SelfSignature.FlagSign &&
-		!i.SelfSignature.KeyExpired(now) {
-		return Key{e, e.PrimaryKey, e.PrivateKey, i.SelfSignature}, true
-	}
-
-	return Key{}, false
-}
-
-// An EntityList contains one or more Entities.
-type EntityList []*Entity
-
-// KeysById returns the set of keys that have the given key id.
-func (el EntityList) KeysById(id uint64) (keys []Key) {
-	for _, e := range el {
-		if e.PrimaryKey.KeyId == id {
-			var selfSig *packet.Signature
-			for _, ident := range e.Identities {
-				if selfSig == nil {
-					selfSig = ident.SelfSignature
-				} else if ident.SelfSignature.IsPrimaryId != nil && *ident.SelfSignature.IsPrimaryId {
-					selfSig = ident.SelfSignature
-					break
-				}
-			}
-			keys = append(keys, Key{e, e.PrimaryKey, e.PrivateKey, selfSig})
-		}
-
-		for _, subKey := range e.Subkeys {
-			if subKey.PublicKey.KeyId == id {
-				keys = append(keys, Key{e, subKey.PublicKey, subKey.PrivateKey, subKey.Sig})
-			}
-		}
-	}
-	return
-}
-
-// KeysByIdAndUsage returns the set of keys with the given id that also meet
-// the key usage given by requiredUsage.  The requiredUsage is expressed as
-// the bitwise-OR of packet.KeyFlag* values.
-func (el EntityList) KeysByIdUsage(id uint64, requiredUsage byte) (keys []Key) {
-	for _, key := range el.KeysById(id) {
-		if len(key.Entity.Revocations) > 0 {
-			continue
-		}
-
-		if key.SelfSignature.RevocationReason != nil {
-			continue
-		}
-
-		if key.SelfSignature.FlagsValid && requiredUsage != 0 {
-			var usage byte
-			if key.SelfSignature.FlagCertify {
-				usage |= packet.KeyFlagCertify
-			}
-			if key.SelfSignature.FlagSign {
-				usage |= packet.KeyFlagSign
-			}
-			if key.SelfSignature.FlagEncryptCommunications {
-				usage |= packet.KeyFlagEncryptCommunications
-			}
-			if key.SelfSignature.FlagEncryptStorage {
-				usage |= packet.KeyFlagEncryptStorage
-			}
-			if usage&requiredUsage != requiredUsage {
-				continue
-			}
-		}
-
-		keys = append(keys, key)
-	}
-	return
-}
-
-// DecryptionKeys returns all private keys that are valid for decryption.
-func (el EntityList) DecryptionKeys() (keys []Key) {
-	for _, e := range el {
-		for _, subKey := range e.Subkeys {
-			if subKey.PrivateKey != nil && (!subKey.Sig.FlagsValid || subKey.Sig.FlagEncryptStorage || subKey.Sig.FlagEncryptCommunications) {
-				keys = append(keys, Key{e, subKey.PublicKey, subKey.PrivateKey, subKey.Sig})
-			}
-		}
-	}
-	return
-}
-
-// ReadArmoredKeyRing reads one or more public/private keys from an armor keyring file.
-func ReadArmoredKeyRing(r io.Reader) (EntityList, error) {
-	block, err := armor.Decode(r)
-	if err == io.EOF {
-		return nil, errors.InvalidArgumentError("no armored data found")
-	}
-	if err != nil {
-		return nil, err
-	}
-	if block.Type != PublicKeyType && block.Type != PrivateKeyType {
-		return nil, errors.InvalidArgumentError("expected public or private key block, got: " + block.Type)
-	}
-
-	return ReadKeyRing(block.Body)
-}
-
-// ReadKeyRing reads one or more public/private keys. Unsupported keys are
-// ignored as long as at least a single valid key is found.
-func ReadKeyRing(r io.Reader) (el EntityList, err error) {
-	packets := packet.NewReader(r)
-	var lastUnsupportedError error
-
-	for {
-		var e *Entity
-		e, err = ReadEntity(packets)
-		if err != nil {
-			// TODO: warn about skipped unsupported/unreadable keys
-			if _, ok := err.(errors.UnsupportedError); ok {
-				lastUnsupportedError = err
-				err = readToNextPublicKey(packets)
-			} else if _, ok := err.(errors.StructuralError); ok {
-				// Skip unreadable, badly-formatted keys
-				lastUnsupportedError = err
-				err = readToNextPublicKey(packets)
-			}
-			if err == io.EOF {
-				err = nil
-				break
-			}
-			if err != nil {
-				el = nil
-				break
-			}
-		} else {
-			el = append(el, e)
-		}
-	}
-
-	if len(el) == 0 && err == nil {
-		err = lastUnsupportedError
-	}
-	return
-}
-
-// readToNextPublicKey reads packets until the start of the entity and leaves
-// the first packet of the new entity in the Reader.
-func readToNextPublicKey(packets *packet.Reader) (err error) {
-	var p packet.Packet
-	for {
-		p, err = packets.Next()
-		if err == io.EOF {
-			return
-		} else if err != nil {
-			if _, ok := err.(errors.UnsupportedError); ok {
-				err = nil
-				continue
-			}
-			return
-		}
-
-		if pk, ok := p.(*packet.PublicKey); ok && !pk.IsSubkey {
-			packets.Unread(p)
-			return
-		}
-	}
-}
-
-// ReadEntity reads an entity (public key, identities, subkeys etc) from the
-// given Reader.
-func ReadEntity(packets *packet.Reader) (*Entity, error) {
-	e := new(Entity)
-	e.Identities = make(map[string]*Identity)
-
-	p, err := packets.Next()
-	if err != nil {
-		return nil, err
-	}
-
-	var ok bool
-	if e.PrimaryKey, ok = p.(*packet.PublicKey); !ok {
-		if e.PrivateKey, ok = p.(*packet.PrivateKey); !ok {
-			packets.Unread(p)
-			return nil, errors.StructuralError("first packet was not a public/private key")
-		} else {
-			e.PrimaryKey = &e.PrivateKey.PublicKey
-		}
-	}
-
-	if !e.PrimaryKey.PubKeyAlgo.CanSign() {
-		return nil, errors.StructuralError("primary key cannot be used for signatures")
-	}
-
-	var current *Identity
-	var revocations []*packet.Signature
-EachPacket:
-	for {
-		p, err := packets.Next()
-		if err == io.EOF {
-			break
-		} else if err != nil {
-			return nil, err
-		}
-
-		switch pkt := p.(type) {
-		case *packet.UserId:
-			current = new(Identity)
-			current.Name = pkt.Id
-			current.UserId = pkt
-			e.Identities[pkt.Id] = current
-
-			for {
-				p, err = packets.Next()
-				if err == io.EOF {
-					return nil, io.ErrUnexpectedEOF
-				} else if err != nil {
-					return nil, err
-				}
-
-				sig, ok := p.(*packet.Signature)
-				if !ok {
-					return nil, errors.StructuralError("user ID packet not followed by self-signature")
-				}
-
-				if (sig.SigType == packet.SigTypePositiveCert || sig.SigType == packet.SigTypeGenericCert) && sig.IssuerKeyId != nil && *sig.IssuerKeyId == e.PrimaryKey.KeyId {
-					if err = e.PrimaryKey.VerifyUserIdSignature(pkt.Id, e.PrimaryKey, sig); err != nil {
-						return nil, errors.StructuralError("user ID self-signature invalid: " + err.Error())
-					}
-					current.SelfSignature = sig
-					break
-				}
-				current.Signatures = append(current.Signatures, sig)
-			}
-		case *packet.Signature:
-			if pkt.SigType == packet.SigTypeKeyRevocation {
-				revocations = append(revocations, pkt)
-			} else if pkt.SigType == packet.SigTypeDirectSignature {
-				// TODO: RFC4880 5.2.1 permits signatures
-				// directly on keys (eg. to bind additional
-				// revocation keys).
-			} else if current == nil {
-				return nil, errors.StructuralError("signature packet found before user id packet")
-			} else {
-				current.Signatures = append(current.Signatures, pkt)
-			}
-		case *packet.PrivateKey:
-			if pkt.IsSubkey == false {
-				packets.Unread(p)
-				break EachPacket
-			}
-			err = addSubkey(e, packets, &pkt.PublicKey, pkt)
-			if err != nil {
-				return nil, err
-			}
-		case *packet.PublicKey:
-			if pkt.IsSubkey == false {
-				packets.Unread(p)
-				break EachPacket
-			}
-			err = addSubkey(e, packets, pkt, nil)
-			if err != nil {
-				return nil, err
-			}
-		default:
-			// we ignore unknown packets
-		}
-	}
-
-	if len(e.Identities) == 0 {
-		return nil, errors.StructuralError("entity without any identities")
-	}
-
-	for _, revocation := range revocations {
-		err = e.PrimaryKey.VerifyRevocationSignature(revocation)
-		if err == nil {
-			e.Revocations = append(e.Revocations, revocation)
-		} else {
-			// TODO: RFC 4880 5.2.3.15 defines revocation keys.
-			return nil, errors.StructuralError("revocation signature signed by alternate key")
-		}
-	}
-
-	return e, nil
-}
-
-func addSubkey(e *Entity, packets *packet.Reader, pub *packet.PublicKey, priv *packet.PrivateKey) error {
-	var subKey Subkey
-	subKey.PublicKey = pub
-	subKey.PrivateKey = priv
-	p, err := packets.Next()
-	if err == io.EOF {
-		return io.ErrUnexpectedEOF
-	}
-	if err != nil {
-		return errors.StructuralError("subkey signature invalid: " + err.Error())
-	}
-	var ok bool
-	subKey.Sig, ok = p.(*packet.Signature)
-	if !ok {
-		return errors.StructuralError("subkey packet not followed by signature")
-	}
-	if subKey.Sig.SigType != packet.SigTypeSubkeyBinding && subKey.Sig.SigType != packet.SigTypeSubkeyRevocation {
-		return errors.StructuralError("subkey signature with wrong type")
-	}
-	err = e.PrimaryKey.VerifyKeySignature(subKey.PublicKey, subKey.Sig)
-	if err != nil {
-		return errors.StructuralError("subkey signature invalid: " + err.Error())
-	}
-	e.Subkeys = append(e.Subkeys, subKey)
-	return nil
-}
-
-const defaultRSAKeyBits = 2048
-
-// NewEntity returns an Entity that contains a fresh RSA/RSA keypair with a
-// single identity composed of the given full name, comment and email, any of
-// which may be empty but must not contain any of "()<>\x00".
-// If config is nil, sensible defaults will be used.
-func NewEntity(name, comment, email string, config *packet.Config) (*Entity, error) {
-	currentTime := config.Now()
-
-	bits := defaultRSAKeyBits
-	if config != nil && config.RSABits != 0 {
-		bits = config.RSABits
-	}
-
-	uid := packet.NewUserId(name, comment, email)
-	if uid == nil {
-		return nil, errors.InvalidArgumentError("user id field contained invalid characters")
-	}
-	signingPriv, err := rsa.GenerateKey(config.Random(), bits)
-	if err != nil {
-		return nil, err
-	}
-	encryptingPriv, err := rsa.GenerateKey(config.Random(), bits)
-	if err != nil {
-		return nil, err
-	}
-
-	e := &Entity{
-		PrimaryKey: packet.NewRSAPublicKey(currentTime, &signingPriv.PublicKey),
-		PrivateKey: packet.NewRSAPrivateKey(currentTime, signingPriv),
-		Identities: make(map[string]*Identity),
-	}
-	isPrimaryId := true
-	e.Identities[uid.Id] = &Identity{
-		Name:   uid.Name,
-		UserId: uid,
-		SelfSignature: &packet.Signature{
-			CreationTime: currentTime,
-			SigType:      packet.SigTypePositiveCert,
-			PubKeyAlgo:   packet.PubKeyAlgoRSA,
-			Hash:         config.Hash(),
-			IsPrimaryId:  &isPrimaryId,
-			FlagsValid:   true,
-			FlagSign:     true,
-			FlagCertify:  true,
-			IssuerKeyId:  &e.PrimaryKey.KeyId,
-		},
-	}
-
-	// If the user passes in a DefaultHash via packet.Config,
-	// set the PreferredHash for the SelfSignature.
-	if config != nil && config.DefaultHash != 0 {
-		e.Identities[uid.Id].SelfSignature.PreferredHash = []uint8{hashToHashId(config.DefaultHash)}
-	}
-
-	e.Subkeys = make([]Subkey, 1)
-	e.Subkeys[0] = Subkey{
-		PublicKey:  packet.NewRSAPublicKey(currentTime, &encryptingPriv.PublicKey),
-		PrivateKey: packet.NewRSAPrivateKey(currentTime, encryptingPriv),
-		Sig: &packet.Signature{
-			CreationTime:              currentTime,
-			SigType:                   packet.SigTypeSubkeyBinding,
-			PubKeyAlgo:                packet.PubKeyAlgoRSA,
-			Hash:                      config.Hash(),
-			FlagsValid:                true,
-			FlagEncryptStorage:        true,
-			FlagEncryptCommunications: true,
-			IssuerKeyId:               &e.PrimaryKey.KeyId,
-		},
-	}
-	e.Subkeys[0].PublicKey.IsSubkey = true
-	e.Subkeys[0].PrivateKey.IsSubkey = true
-
-	return e, nil
-}
-
-// SerializePrivate serializes an Entity, including private key material, to
-// the given Writer. For now, it must only be used on an Entity returned from
-// NewEntity.
-// If config is nil, sensible defaults will be used.
-func (e *Entity) SerializePrivate(w io.Writer, config *packet.Config) (err error) {
-	err = e.PrivateKey.Serialize(w)
-	if err != nil {
-		return
-	}
-	for _, ident := range e.Identities {
-		err = ident.UserId.Serialize(w)
-		if err != nil {
-			return
-		}
-		err = ident.SelfSignature.SignUserId(ident.UserId.Id, e.PrimaryKey, e.PrivateKey, config)
-		if err != nil {
-			return
-		}
-		err = ident.SelfSignature.Serialize(w)
-		if err != nil {
-			return
-		}
-	}
-	for _, subkey := range e.Subkeys {
-		err = subkey.PrivateKey.Serialize(w)
-		if err != nil {
-			return
-		}
-		err = subkey.Sig.SignKey(subkey.PublicKey, e.PrivateKey, config)
-		if err != nil {
-			return
-		}
-		err = subkey.Sig.Serialize(w)
-		if err != nil {
-			return
-		}
-	}
-	return nil
-}
-
-// Serialize writes the public part of the given Entity to w. (No private
-// key material will be output).
-func (e *Entity) Serialize(w io.Writer) error {
-	err := e.PrimaryKey.Serialize(w)
-	if err != nil {
-		return err
-	}
-	for _, ident := range e.Identities {
-		err = ident.UserId.Serialize(w)
-		if err != nil {
-			return err
-		}
-		err = ident.SelfSignature.Serialize(w)
-		if err != nil {
-			return err
-		}
-		for _, sig := range ident.Signatures {
-			err = sig.Serialize(w)
-			if err != nil {
-				return err
-			}
-		}
-	}
-	for _, subkey := range e.Subkeys {
-		err = subkey.PublicKey.Serialize(w)
-		if err != nil {
-			return err
-		}
-		err = subkey.Sig.Serialize(w)
-		if err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-// SignIdentity adds a signature to e, from signer, attesting that identity is
-// associated with e. The provided identity must already be an element of
-// e.Identities and the private key of signer must have been decrypted if
-// necessary.
-// If config is nil, sensible defaults will be used.
-func (e *Entity) SignIdentity(identity string, signer *Entity, config *packet.Config) error {
-	if signer.PrivateKey == nil {
-		return errors.InvalidArgumentError("signing Entity must have a private key")
-	}
-	if signer.PrivateKey.Encrypted {
-		return errors.InvalidArgumentError("signing Entity's private key must be decrypted")
-	}
-	ident, ok := e.Identities[identity]
-	if !ok {
-		return errors.InvalidArgumentError("given identity string not found in Entity")
-	}
-
-	sig := &packet.Signature{
-		SigType:      packet.SigTypeGenericCert,
-		PubKeyAlgo:   signer.PrivateKey.PubKeyAlgo,
-		Hash:         config.Hash(),
-		CreationTime: config.Now(),
-		IssuerKeyId:  &signer.PrivateKey.KeyId,
-	}
-	if err := sig.SignUserId(identity, e.PrimaryKey, signer.PrivateKey, config); err != nil {
-		return err
-	}
-	ident.Signatures = append(ident.Signatures, sig)
-	return nil
-}

vendor/vendor.json

@@ -515,6 +515,84 @@
 			"revision": "b2c7a7da5b2995941048f60146e67702a292e468",
 			"revisionTime": "2016-02-12T04:00:40Z"
 		},
+		{
+			"checksumSHA1": "VJk3rOWfxEV9Ilig5lgzH1qg8Ss=",
+			"path": "github.com/keybase/go-crypto/brainpool",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "rnRjEJs5luF+DIXp2J6LFcQk8Gg=",
+			"path": "github.com/keybase/go-crypto/cast5",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "F5++ZQS5Vt7hd6lxPCKTffvph1A=",
+			"path": "github.com/keybase/go-crypto/curve25519",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "IvrDXwIixB5yPPbo6tq1/1cSn78=",
+			"path": "github.com/keybase/go-crypto/ed25519",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "4+fslB6pCbplNq4viy6CrOkkY6Y=",
+			"path": "github.com/keybase/go-crypto/ed25519/internal/edwards25519",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "fgFlkfkaotUjBVhJik2979oCeJw=",
+			"path": "github.com/keybase/go-crypto/openpgp",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "+spfcEChljh3yeIg4K/xHOQ2pVM=",
+			"path": "github.com/keybase/go-crypto/openpgp/armor",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "nWhmwjBJqPSvkCWqaap2Z9EiS1k=",
+			"path": "github.com/keybase/go-crypto/openpgp/ecdh",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "uxXG9IC/XF8jwwvZUbW65+x8/+M=",
+			"path": "github.com/keybase/go-crypto/openpgp/elgamal",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "EyUf82Yknzc75m8RcA21CNQINw0=",
+			"path": "github.com/keybase/go-crypto/openpgp/errors",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "y16ATKgHL/k6rQZqdXP1sIAJxE0=",
+			"path": "github.com/keybase/go-crypto/openpgp/packet",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "BGDxg1Xtsz0DSPzdQGJLLQqfYc8=",
+			"path": "github.com/keybase/go-crypto/openpgp/s2k",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
+		{
+			"checksumSHA1": "rE3pp7b3gfcmBregzpIvN5IdFhY=",
+			"path": "github.com/keybase/go-crypto/rsa",
+			"revision": "00ac4db533f63ef97576cbc7b07939ff7daf7329",
+			"revisionTime": "2017-06-05T14:56:57Z"
+		},
 		{
 			"checksumSHA1": "fh+CcgeUUsnuwSORHYWg0ycbp+4=",
 			"path": "github.com/klauspost/compress/flate",
@@ -1182,12 +1260,6 @@
 			"revision": "2c050d2dae5345c417db301f11fda6fbf5ad0f0a",
 			"revisionTime": "2016-09-14T08:04:27Z"
 		},
-		{
-			"checksumSHA1": "TT1rac6kpQp2vz24m5yDGUNQ/QQ=",
-			"path": "golang.org/x/crypto/cast5",
-			"revision": "b8a2a83acfe6e6770b75de42d5ff4c67596675c0",
-			"revisionTime": "2017-01-13T19:21:00Z"
-		},
 		{
 			"checksumSHA1": "dwOedwBJ1EIK9+S3t108Bx054Y8=",
 			"path": "golang.org/x/crypto/curve25519",
@@ -1212,42 +1284,6 @@
 			"revision": "ede567c8e044a5913dad1d1af3696d9da953104c",
 			"revisionTime": "2016-11-04T19:41:44Z"
 		},
-		{
-			"checksumSHA1": "IIhFTrLlmlc6lEFSitqi4aw2lw0=",
-			"path": "golang.org/x/crypto/openpgp",
-			"revision": "b8a2a83acfe6e6770b75de42d5ff4c67596675c0",
-			"revisionTime": "2017-01-13T19:21:00Z"
-		},
-		{
-			"checksumSHA1": "olOKkhrdkYQHZ0lf1orrFQPQrv4=",
-			"path": "golang.org/x/crypto/openpgp/armor",
-			"revision": "b8a2a83acfe6e6770b75de42d5ff4c67596675c0",
-			"revisionTime": "2017-01-13T19:21:00Z"
-		},
-		{
-			"checksumSHA1": "eo/KtdjieJQXH7Qy+faXFcF70ME=",
-			"path": "golang.org/x/crypto/openpgp/elgamal",
-			"revision": "b8a2a83acfe6e6770b75de42d5ff4c67596675c0",
-			"revisionTime": "2017-01-13T19:21:00Z"
-		},
-		{
-			"checksumSHA1": "rlxVSaGgqdAgwblsErxTxIfuGfg=",
-			"path": "golang.org/x/crypto/openpgp/errors",
-			"revision": "b8a2a83acfe6e6770b75de42d5ff4c67596675c0",
-			"revisionTime": "2017-01-13T19:21:00Z"
-		},
-		{
-			"checksumSHA1": "LWdaR8Q9yn6eBCcnGl0HvJRDUBE=",
-			"path": "golang.org/x/crypto/openpgp/packet",
-			"revision": "b8a2a83acfe6e6770b75de42d5ff4c67596675c0",
-			"revisionTime": "2017-01-13T19:21:00Z"
-		},
-		{
-			"checksumSHA1": "s2qT4UwvzBSkzXuiuMkowif1Olw=",
-			"path": "golang.org/x/crypto/openpgp/s2k",
-			"revision": "b8a2a83acfe6e6770b75de42d5ff4c67596675c0",
-			"revisionTime": "2017-01-13T19:21:00Z"
-		},
 		{
 			"checksumSHA1": "1MGpGDQqnUoRpv7VEcQrXOBydXE=",
 			"path": "golang.org/x/crypto/pbkdf2",