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mirror of https://git.zx2c4.com/wireguard-windows synced 2024-11-10 16:59:18 +00:00
wireguard-windows/conf/parser.go
Jason A. Donenfeld 6ed37f30f5 global: bump date
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-06 17:28:13 +01:00

401 lines
9.9 KiB
Go

/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2019-2022 WireGuard LLC. All Rights Reserved.
*/
package conf
import (
"encoding/base64"
"net/netip"
"strconv"
"strings"
"golang.org/x/sys/windows"
"golang.org/x/text/encoding/unicode"
"golang.zx2c4.com/wireguard/windows/driver"
"golang.zx2c4.com/wireguard/windows/l18n"
)
type ParseError struct {
why string
offender string
}
func (e *ParseError) Error() string {
return l18n.Sprintf("%s: %q", e.why, e.offender)
}
func parseIPCidr(s string) (netip.Prefix, error) {
ipcidr, err := netip.ParsePrefix(s)
if err == nil {
return ipcidr, nil
}
addr, err := netip.ParseAddr(s)
if err != nil {
return netip.Prefix{}, &ParseError{l18n.Sprintf("Invalid IP address: "), s}
}
return netip.PrefixFrom(addr, addr.BitLen()), nil
}
func parseEndpoint(s string) (*Endpoint, error) {
i := strings.LastIndexByte(s, ':')
if i < 0 {
return nil, &ParseError{l18n.Sprintf("Missing port from endpoint"), s}
}
host, portStr := s[:i], s[i+1:]
if len(host) < 1 {
return nil, &ParseError{l18n.Sprintf("Invalid endpoint host"), host}
}
port, err := parsePort(portStr)
if err != nil {
return nil, err
}
hostColon := strings.IndexByte(host, ':')
if host[0] == '[' || host[len(host)-1] == ']' || hostColon > 0 {
err := &ParseError{l18n.Sprintf("Brackets must contain an IPv6 address"), host}
if len(host) > 3 && host[0] == '[' && host[len(host)-1] == ']' && hostColon > 0 {
end := len(host) - 1
if i := strings.LastIndexByte(host, '%'); i > 1 {
end = i
}
maybeV6, err2 := netip.ParseAddr(host[1:end])
if err2 != nil || !maybeV6.Is6() {
return nil, err
}
} else {
return nil, err
}
host = host[1 : len(host)-1]
}
return &Endpoint{host, port}, nil
}
func parseMTU(s string) (uint16, error) {
m, err := strconv.Atoi(s)
if err != nil {
return 0, err
}
if m < 576 || m > 65535 {
return 0, &ParseError{l18n.Sprintf("Invalid MTU"), s}
}
return uint16(m), nil
}
func parsePort(s string) (uint16, error) {
m, err := strconv.Atoi(s)
if err != nil {
return 0, err
}
if m < 0 || m > 65535 {
return 0, &ParseError{l18n.Sprintf("Invalid port"), s}
}
return uint16(m), nil
}
func parsePersistentKeepalive(s string) (uint16, error) {
if s == "off" {
return 0, nil
}
m, err := strconv.Atoi(s)
if err != nil {
return 0, err
}
if m < 0 || m > 65535 {
return 0, &ParseError{l18n.Sprintf("Invalid persistent keepalive"), s}
}
return uint16(m), nil
}
func parseTableOff(s string) (bool, error) {
if s == "off" {
return true, nil
} else if s == "auto" || s == "main" {
return false, nil
}
_, err := strconv.ParseUint(s, 10, 32)
return false, err
}
func parseKeyBase64(s string) (*Key, error) {
k, err := base64.StdEncoding.DecodeString(s)
if err != nil {
return nil, &ParseError{l18n.Sprintf("Invalid key: %v", err), s}
}
if len(k) != KeyLength {
return nil, &ParseError{l18n.Sprintf("Keys must decode to exactly 32 bytes"), s}
}
var key Key
copy(key[:], k)
return &key, nil
}
func splitList(s string) ([]string, error) {
var out []string
for _, split := range strings.Split(s, ",") {
trim := strings.TrimSpace(split)
if len(trim) == 0 {
return nil, &ParseError{l18n.Sprintf("Two commas in a row"), s}
}
out = append(out, trim)
}
return out, nil
}
type parserState int
const (
inInterfaceSection parserState = iota
inPeerSection
notInASection
)
func (c *Config) maybeAddPeer(p *Peer) {
if p != nil {
c.Peers = append(c.Peers, *p)
}
}
func FromWgQuick(s, name string) (*Config, error) {
if !TunnelNameIsValid(name) {
return nil, &ParseError{l18n.Sprintf("Tunnel name is not valid"), name}
}
lines := strings.Split(s, "\n")
parserState := notInASection
conf := Config{Name: name}
sawPrivateKey := false
var peer *Peer
for _, line := range lines {
line, _, _ = strings.Cut(line, "#")
line = strings.TrimSpace(line)
lineLower := strings.ToLower(line)
if len(line) == 0 {
continue
}
if lineLower == "[interface]" {
conf.maybeAddPeer(peer)
parserState = inInterfaceSection
continue
}
if lineLower == "[peer]" {
conf.maybeAddPeer(peer)
peer = &Peer{}
parserState = inPeerSection
continue
}
if parserState == notInASection {
return nil, &ParseError{l18n.Sprintf("Line must occur in a section"), line}
}
equals := strings.IndexByte(line, '=')
if equals < 0 {
return nil, &ParseError{l18n.Sprintf("Config key is missing an equals separator"), line}
}
key, val := strings.TrimSpace(lineLower[:equals]), strings.TrimSpace(line[equals+1:])
if len(val) == 0 {
return nil, &ParseError{l18n.Sprintf("Key must have a value"), line}
}
if parserState == inInterfaceSection {
switch key {
case "privatekey":
k, err := parseKeyBase64(val)
if err != nil {
return nil, err
}
conf.Interface.PrivateKey = *k
sawPrivateKey = true
case "listenport":
p, err := parsePort(val)
if err != nil {
return nil, err
}
conf.Interface.ListenPort = p
case "mtu":
m, err := parseMTU(val)
if err != nil {
return nil, err
}
conf.Interface.MTU = m
case "address":
addresses, err := splitList(val)
if err != nil {
return nil, err
}
for _, address := range addresses {
a, err := parseIPCidr(address)
if err != nil {
return nil, err
}
conf.Interface.Addresses = append(conf.Interface.Addresses, a)
}
case "dns":
addresses, err := splitList(val)
if err != nil {
return nil, err
}
for _, address := range addresses {
a, err := netip.ParseAddr(address)
if err != nil {
conf.Interface.DNSSearch = append(conf.Interface.DNSSearch, address)
} else {
conf.Interface.DNS = append(conf.Interface.DNS, a)
}
}
case "preup":
conf.Interface.PreUp = val
case "postup":
conf.Interface.PostUp = val
case "predown":
conf.Interface.PreDown = val
case "postdown":
conf.Interface.PostDown = val
case "table":
tableOff, err := parseTableOff(val)
if err != nil {
return nil, err
}
conf.Interface.TableOff = tableOff
default:
return nil, &ParseError{l18n.Sprintf("Invalid key for [Interface] section"), key}
}
} else if parserState == inPeerSection {
switch key {
case "publickey":
k, err := parseKeyBase64(val)
if err != nil {
return nil, err
}
peer.PublicKey = *k
case "presharedkey":
k, err := parseKeyBase64(val)
if err != nil {
return nil, err
}
peer.PresharedKey = *k
case "allowedips":
addresses, err := splitList(val)
if err != nil {
return nil, err
}
for _, address := range addresses {
a, err := parseIPCidr(address)
if err != nil {
return nil, err
}
peer.AllowedIPs = append(peer.AllowedIPs, a)
}
case "persistentkeepalive":
p, err := parsePersistentKeepalive(val)
if err != nil {
return nil, err
}
peer.PersistentKeepalive = p
case "endpoint":
e, err := parseEndpoint(val)
if err != nil {
return nil, err
}
peer.Endpoint = *e
default:
return nil, &ParseError{l18n.Sprintf("Invalid key for [Peer] section"), key}
}
}
}
conf.maybeAddPeer(peer)
if !sawPrivateKey {
return nil, &ParseError{l18n.Sprintf("An interface must have a private key"), l18n.Sprintf("[none specified]")}
}
for _, p := range conf.Peers {
if p.PublicKey.IsZero() {
return nil, &ParseError{l18n.Sprintf("All peers must have public keys"), l18n.Sprintf("[none specified]")}
}
}
return &conf, nil
}
func FromWgQuickWithUnknownEncoding(s, name string) (*Config, error) {
c, firstErr := FromWgQuick(s, name)
if firstErr == nil {
return c, nil
}
for _, encoding := range unicode.All {
decoded, err := encoding.NewDecoder().String(s)
if err == nil {
c, err := FromWgQuick(decoded, name)
if err == nil {
return c, nil
}
}
}
return nil, firstErr
}
func FromDriverConfiguration(interfaze *driver.Interface, existingConfig *Config) *Config {
conf := Config{
Name: existingConfig.Name,
Interface: Interface{
Addresses: existingConfig.Interface.Addresses,
DNS: existingConfig.Interface.DNS,
DNSSearch: existingConfig.Interface.DNSSearch,
MTU: existingConfig.Interface.MTU,
PreUp: existingConfig.Interface.PreUp,
PostUp: existingConfig.Interface.PostUp,
PreDown: existingConfig.Interface.PreDown,
PostDown: existingConfig.Interface.PostDown,
TableOff: existingConfig.Interface.TableOff,
},
}
if interfaze.Flags&driver.InterfaceHasPrivateKey != 0 {
conf.Interface.PrivateKey = interfaze.PrivateKey
}
if interfaze.Flags&driver.InterfaceHasListenPort != 0 {
conf.Interface.ListenPort = interfaze.ListenPort
}
var p *driver.Peer
for i := uint32(0); i < interfaze.PeerCount; i++ {
if p == nil {
p = interfaze.FirstPeer()
} else {
p = p.NextPeer()
}
peer := Peer{}
if p.Flags&driver.PeerHasPublicKey != 0 {
peer.PublicKey = p.PublicKey
}
if p.Flags&driver.PeerHasPresharedKey != 0 {
peer.PresharedKey = p.PresharedKey
}
if p.Flags&driver.PeerHasEndpoint != 0 {
peer.Endpoint.Port = p.Endpoint.Port()
peer.Endpoint.Host = p.Endpoint.Addr().String()
}
if p.Flags&driver.PeerHasPersistentKeepalive != 0 {
peer.PersistentKeepalive = p.PersistentKeepalive
}
peer.TxBytes = Bytes(p.TxBytes)
peer.RxBytes = Bytes(p.RxBytes)
if p.LastHandshake != 0 {
peer.LastHandshakeTime = HandshakeTime((p.LastHandshake - 116444736000000000) * 100)
}
var a *driver.AllowedIP
for j := uint32(0); j < p.AllowedIPsCount; j++ {
if a == nil {
a = p.FirstAllowedIP()
} else {
a = a.NextAllowedIP()
}
var ip netip.Addr
if a.AddressFamily == windows.AF_INET {
ip = netip.AddrFrom4(*(*[4]byte)(a.Address[:4]))
} else if a.AddressFamily == windows.AF_INET6 {
ip = netip.AddrFrom16(*(*[16]byte)(a.Address[:16]))
}
peer.AllowedIPs = append(peer.AllowedIPs, netip.PrefixFrom(ip, int(a.Cidr)))
}
conf.Peers = append(conf.Peers, peer)
}
return &conf
}