You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
gitea/modules/hostmatcher/hostmatcher.go

158 lines
4.2 KiB

// Copyright 2021 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package hostmatcher
import (
"net"
"path/filepath"
"strings"
)
// HostMatchList is used to check if a host or IP is in a list.
type HostMatchList struct {
SettingKeyHint string
SettingValue string
// builtins networks
builtins []string
// patterns for host names (with wildcard support)
patterns []string
// ipNets is the CIDR network list
ipNets []*net.IPNet
}
// MatchBuiltinExternal A valid non-private unicast IP, all hosts on public internet are matched
const MatchBuiltinExternal = "external"
// MatchBuiltinPrivate RFC 1918 (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) and RFC 4193 (FC00::/7). Also called LAN/Intranet.
const MatchBuiltinPrivate = "private"
// MatchBuiltinLoopback 127.0.0.0/8 for IPv4 and ::1/128 for IPv6, localhost is included.
const MatchBuiltinLoopback = "loopback"
func isBuiltin(s string) bool {
return s == MatchBuiltinExternal || s == MatchBuiltinPrivate || s == MatchBuiltinLoopback
}
// ParseHostMatchList parses the host list HostMatchList
func ParseHostMatchList(settingKeyHint, hostList string) *HostMatchList {
hl := &HostMatchList{SettingKeyHint: settingKeyHint, SettingValue: hostList}
for _, s := range strings.Split(hostList, ",") {
s = strings.ToLower(strings.TrimSpace(s))
if s == "" {
continue
}
_, ipNet, err := net.ParseCIDR(s)
if err == nil {
hl.ipNets = append(hl.ipNets, ipNet)
} else if isBuiltin(s) {
hl.builtins = append(hl.builtins, s)
} else {
hl.patterns = append(hl.patterns, s)
}
}
return hl
}
// ParseSimpleMatchList parse a simple matchlist (no built-in networks, no CIDR support, only wildcard pattern match)
func ParseSimpleMatchList(settingKeyHint, matchList string) *HostMatchList {
hl := &HostMatchList{
SettingKeyHint: settingKeyHint,
SettingValue: matchList,
}
for _, s := range strings.Split(matchList, ",") {
s = strings.ToLower(strings.TrimSpace(s))
if s == "" {
continue
}
// we keep the same result as old `matchlist`, so no builtin/CIDR support here, we only match wildcard patterns
hl.patterns = append(hl.patterns, s)
}
return hl
}
// AppendBuiltin appends more builtins to match
func (hl *HostMatchList) AppendBuiltin(builtin string) {
hl.builtins = append(hl.builtins, builtin)
}
// IsEmpty checks if the checklist is empty
func (hl *HostMatchList) IsEmpty() bool {
return hl == nil || (len(hl.builtins) == 0 && len(hl.patterns) == 0 && len(hl.ipNets) == 0)
}
func (hl *HostMatchList) checkPattern(host string) bool {
host = strings.ToLower(strings.TrimSpace(host))
for _, pattern := range hl.patterns {
if matched, _ := filepath.Match(pattern, host); matched {
return true
}
}
return false
}
func (hl *HostMatchList) checkIP(ip net.IP) bool {
for _, pattern := range hl.patterns {
if pattern == "*" {
return true
}
}
for _, builtin := range hl.builtins {
switch builtin {
case MatchBuiltinExternal:
if ip.IsGlobalUnicast() && !ip.IsPrivate() {
return true
}
case MatchBuiltinPrivate:
if ip.IsPrivate() {
return true
}
case MatchBuiltinLoopback:
if ip.IsLoopback() {
return true
}
}
}
for _, ipNet := range hl.ipNets {
if ipNet.Contains(ip) {
return true
}
}
return false
}
// MatchHostName checks if the host matches an allow/deny(block) list
func (hl *HostMatchList) MatchHostName(host string) bool {
hostname, _, err := net.SplitHostPort(host)
if err != nil {
hostname = host
}
if hl == nil {
return false
}
if hl.checkPattern(hostname) {
return true
}
if ip := net.ParseIP(hostname); ip != nil {
return hl.checkIP(ip)
}
return false
}
// MatchIPAddr checks if the IP matches an allow/deny(block) list, it's safe to pass `nil` to `ip`
func (hl *HostMatchList) MatchIPAddr(ip net.IP) bool {
if hl == nil {
return false
}
host := ip.String() // nil-safe, we will get "<nil>" if ip is nil
return hl.checkPattern(host) || hl.checkIP(ip)
}
// MatchHostOrIP checks if the host or IP matches an allow/deny(block) list
func (hl *HostMatchList) MatchHostOrIP(host string, ip net.IP) bool {
return hl.MatchHostName(host) || hl.MatchIPAddr(ip)
}