EtherGuard-VPN/device/uapi.go
Josh Bleecher Snyder a1c265b0c5 device: simplify UAPI helper methods
bufio is not required.

strings.Builder is cheaper than bytes.Buffer for constructing strings.

io.Writer is more flexible than io.StringWriter,
and just as cheap (when used with io.WriteString).

Run gofmt.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2021-01-07 14:49:44 +01:00

465 lines
10 KiB
Go

/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2017-2020 WireGuard LLC. All Rights Reserved.
*/
package device
import (
"bufio"
"errors"
"fmt"
"io"
"net"
"strconv"
"strings"
"sync/atomic"
"time"
"golang.zx2c4.com/wireguard/conn"
"golang.zx2c4.com/wireguard/ipc"
)
type IPCError struct {
int64
}
func (s IPCError) Error() string {
return fmt.Sprintf("IPC error: %d", s.int64)
}
func (s IPCError) ErrorCode() int64 {
return s.int64
}
func (device *Device) IpcGetOperation(w io.Writer) error {
lines := make([]string, 0, 100)
send := func(line string) {
lines = append(lines, line)
}
func() {
// lock required resources
device.net.RLock()
defer device.net.RUnlock()
device.staticIdentity.RLock()
defer device.staticIdentity.RUnlock()
device.peers.RLock()
defer device.peers.RUnlock()
// serialize device related values
if !device.staticIdentity.privateKey.IsZero() {
send("private_key=" + device.staticIdentity.privateKey.ToHex())
}
if device.net.port != 0 {
send(fmt.Sprintf("listen_port=%d", device.net.port))
}
if device.net.fwmark != 0 {
send(fmt.Sprintf("fwmark=%d", device.net.fwmark))
}
// serialize each peer state
for _, peer := range device.peers.keyMap {
peer.RLock()
defer peer.RUnlock()
send("public_key=" + peer.handshake.remoteStatic.ToHex())
send("preshared_key=" + peer.handshake.presharedKey.ToHex())
send("protocol_version=1")
if peer.endpoint != nil {
send("endpoint=" + peer.endpoint.DstToString())
}
nano := atomic.LoadInt64(&peer.stats.lastHandshakeNano)
secs := nano / time.Second.Nanoseconds()
nano %= time.Second.Nanoseconds()
send(fmt.Sprintf("last_handshake_time_sec=%d", secs))
send(fmt.Sprintf("last_handshake_time_nsec=%d", nano))
send(fmt.Sprintf("tx_bytes=%d", atomic.LoadUint64(&peer.stats.txBytes)))
send(fmt.Sprintf("rx_bytes=%d", atomic.LoadUint64(&peer.stats.rxBytes)))
send(fmt.Sprintf("persistent_keepalive_interval=%d", atomic.LoadUint32(&peer.persistentKeepaliveInterval)))
for _, ip := range device.allowedips.EntriesForPeer(peer) {
send("allowed_ip=" + ip.String())
}
}
}()
// send lines (does not require resource locks)
for _, line := range lines {
_, err := io.WriteString(w, line+"\n")
if err != nil {
return &IPCError{ipc.IpcErrorIO}
}
}
return nil
}
func (device *Device) IpcSetOperation(r io.Reader) error {
scanner := bufio.NewScanner(r)
logError := device.log.Error
logDebug := device.log.Debug
var peer *Peer
dummy := false
createdNewPeer := false
deviceConfig := true
for scanner.Scan() {
// parse line
line := scanner.Text()
if line == "" {
return nil
}
parts := strings.Split(line, "=")
if len(parts) != 2 {
return &IPCError{ipc.IpcErrorProtocol}
}
key := parts[0]
value := parts[1]
/* device configuration */
if deviceConfig {
switch key {
case "private_key":
var sk NoisePrivateKey
err := sk.FromMaybeZeroHex(value)
if err != nil {
logError.Println("Failed to set private_key:", err)
return &IPCError{ipc.IpcErrorInvalid}
}
logDebug.Println("UAPI: Updating private key")
device.SetPrivateKey(sk)
case "listen_port":
// parse port number
port, err := strconv.ParseUint(value, 10, 16)
if err != nil {
logError.Println("Failed to parse listen_port:", err)
return &IPCError{ipc.IpcErrorInvalid}
}
// update port and rebind
logDebug.Println("UAPI: Updating listen port")
device.net.Lock()
device.net.port = uint16(port)
device.net.Unlock()
if err := device.BindUpdate(); err != nil {
logError.Println("Failed to set listen_port:", err)
return &IPCError{ipc.IpcErrorPortInUse}
}
case "fwmark":
// parse fwmark field
fwmark, err := func() (uint32, error) {
if value == "" {
return 0, nil
}
mark, err := strconv.ParseUint(value, 10, 32)
return uint32(mark), err
}()
if err != nil {
logError.Println("Invalid fwmark", err)
return &IPCError{ipc.IpcErrorInvalid}
}
logDebug.Println("UAPI: Updating fwmark")
if err := device.BindSetMark(uint32(fwmark)); err != nil {
logError.Println("Failed to update fwmark:", err)
return &IPCError{ipc.IpcErrorPortInUse}
}
case "public_key":
// switch to peer configuration
logDebug.Println("UAPI: Transition to peer configuration")
deviceConfig = false
case "replace_peers":
if value != "true" {
logError.Println("Failed to set replace_peers, invalid value:", value)
return &IPCError{ipc.IpcErrorInvalid}
}
logDebug.Println("UAPI: Removing all peers")
device.RemoveAllPeers()
default:
logError.Println("Invalid UAPI device key:", key)
return &IPCError{ipc.IpcErrorInvalid}
}
}
/* peer configuration */
if !deviceConfig {
switch key {
case "public_key":
var publicKey NoisePublicKey
err := publicKey.FromHex(value)
if err != nil {
logError.Println("Failed to get peer by public key:", err)
return &IPCError{ipc.IpcErrorInvalid}
}
// ignore peer with public key of device
device.staticIdentity.RLock()
dummy = device.staticIdentity.publicKey.Equals(publicKey)
device.staticIdentity.RUnlock()
if dummy {
peer = &Peer{}
} else {
peer = device.LookupPeer(publicKey)
}
createdNewPeer = peer == nil
if createdNewPeer {
peer, err = device.NewPeer(publicKey)
if err != nil {
logError.Println("Failed to create new peer:", err)
return &IPCError{ipc.IpcErrorInvalid}
}
if peer == nil {
dummy = true
peer = &Peer{}
} else {
logDebug.Println(peer, "- UAPI: Created")
}
}
case "update_only":
// allow disabling of creation
if value != "true" {
logError.Println("Failed to set update only, invalid value:", value)
return &IPCError{ipc.IpcErrorInvalid}
}
if createdNewPeer && !dummy {
device.RemovePeer(peer.handshake.remoteStatic)
peer = &Peer{}
dummy = true
}
case "remove":
// remove currently selected peer from device
if value != "true" {
logError.Println("Failed to set remove, invalid value:", value)
return &IPCError{ipc.IpcErrorInvalid}
}
if !dummy {
logDebug.Println(peer, "- UAPI: Removing")
device.RemovePeer(peer.handshake.remoteStatic)
}
peer = &Peer{}
dummy = true
case "preshared_key":
// update PSK
logDebug.Println(peer, "- UAPI: Updating preshared key")
peer.handshake.mutex.Lock()
err := peer.handshake.presharedKey.FromHex(value)
peer.handshake.mutex.Unlock()
if err != nil {
logError.Println("Failed to set preshared key:", err)
return &IPCError{ipc.IpcErrorInvalid}
}
case "endpoint":
// set endpoint destination
logDebug.Println(peer, "- UAPI: Updating endpoint")
err := func() error {
peer.Lock()
defer peer.Unlock()
endpoint, err := conn.CreateEndpoint(value)
if err != nil {
return err
}
peer.endpoint = endpoint
return nil
}()
if err != nil {
logError.Println("Failed to set endpoint:", err, ":", value)
return &IPCError{ipc.IpcErrorInvalid}
}
case "persistent_keepalive_interval":
// update persistent keepalive interval
logDebug.Println(peer, "- UAPI: Updating persistent keepalive interval")
secs, err := strconv.ParseUint(value, 10, 16)
if err != nil {
logError.Println("Failed to set persistent keepalive interval:", err)
return &IPCError{ipc.IpcErrorInvalid}
}
old := atomic.SwapUint32(&peer.persistentKeepaliveInterval, uint32(secs))
// send immediate keepalive if we're turning it on and before it wasn't on
if old == 0 && secs != 0 {
if err != nil {
logError.Println("Failed to get tun device status:", err)
return &IPCError{ipc.IpcErrorIO}
}
if device.isUp.Get() && !dummy {
peer.SendKeepalive()
}
}
case "replace_allowed_ips":
logDebug.Println(peer, "- UAPI: Removing all allowedips")
if value != "true" {
logError.Println("Failed to replace allowedips, invalid value:", value)
return &IPCError{ipc.IpcErrorInvalid}
}
if dummy {
continue
}
device.allowedips.RemoveByPeer(peer)
case "allowed_ip":
logDebug.Println(peer, "- UAPI: Adding allowedip")
_, network, err := net.ParseCIDR(value)
if err != nil {
logError.Println("Failed to set allowed ip:", err)
return &IPCError{ipc.IpcErrorInvalid}
}
if dummy {
continue
}
ones, _ := network.Mask.Size()
device.allowedips.Insert(network.IP, uint(ones), peer)
case "protocol_version":
if value != "1" {
logError.Println("Invalid protocol version:", value)
return &IPCError{ipc.IpcErrorInvalid}
}
default:
logError.Println("Invalid UAPI peer key:", key)
return &IPCError{ipc.IpcErrorInvalid}
}
}
}
return nil
}
func (device *Device) IpcGet() (string, error) {
buf := new(strings.Builder)
if err := device.IpcGetOperation(buf); err != nil {
return "", err
}
return buf.String(), nil
}
func (device *Device) IpcSet(uapiConf string) error {
return device.IpcSetOperation(strings.NewReader(uapiConf))
}
func (device *Device) IpcHandle(socket net.Conn) {
// create buffered read/writer
defer socket.Close()
buffered := func(s io.ReadWriter) *bufio.ReadWriter {
reader := bufio.NewReader(s)
writer := bufio.NewWriter(s)
return bufio.NewReadWriter(reader, writer)
}(socket)
defer buffered.Flush()
op, err := buffered.ReadString('\n')
if err != nil {
return
}
// handle operation
var status *IPCError
switch op {
case "set=1\n":
err = device.IpcSetOperation(buffered.Reader)
if err != nil && !errors.As(err, &status) {
// should never happen
device.log.Error.Println("Invalid UAPI error:", err)
status = &IPCError{1}
}
case "get=1\n":
err = device.IpcGetOperation(buffered.Writer)
if err != nil && !errors.As(err, &status) {
// should never happen
device.log.Error.Println("Invalid UAPI error:", err)
status = &IPCError{1}
}
default:
device.log.Error.Println("Invalid UAPI operation:", op)
return
}
// write status
if status != nil {
device.log.Error.Println(status)
fmt.Fprintf(buffered, "errno=%d\n\n", status.ErrorCode())
} else {
fmt.Fprintf(buffered, "errno=0\n\n")
}
}