mirror of
https://github.com/yggdrasil-network/yggdrasil-go
synced 2024-11-10 07:20:39 +03:00
383 lines
9.0 KiB
Go
383 lines
9.0 KiB
Go
package yggdrasil
|
|
|
|
// This sends packets to peers using TCP as a transport
|
|
// It's generally better tested than the UDP implementation
|
|
// Using it regularly is insane, but I find TCP easier to test/debug with it
|
|
// Updating and optimizing the UDP version is a higher priority
|
|
|
|
// TODO:
|
|
// Something needs to make sure we're getting *valid* packets
|
|
// Could be used to DoS (connect, give someone else's keys, spew garbage)
|
|
// I guess the "peer" part should watch for link packets, disconnect?
|
|
|
|
import "net"
|
|
import "time"
|
|
import "errors"
|
|
import "sync"
|
|
import "fmt"
|
|
import "golang.org/x/net/proxy"
|
|
|
|
const tcp_msgSize = 2048 + 65535 // TODO figure out what makes sense
|
|
|
|
// wrapper function for non tcp/ip connections
|
|
func setNoDelay(c net.Conn, delay bool) {
|
|
tcp, ok := c.(*net.TCPConn)
|
|
if ok {
|
|
tcp.SetNoDelay(delay)
|
|
}
|
|
}
|
|
|
|
type tcpInterface struct {
|
|
core *Core
|
|
serv net.Listener
|
|
mutex sync.Mutex // Protecting the below
|
|
calls map[string]struct{}
|
|
conns map[tcpInfo](chan struct{})
|
|
}
|
|
|
|
type tcpInfo struct {
|
|
box boxPubKey
|
|
sig sigPubKey
|
|
localAddr string
|
|
remoteAddr string
|
|
}
|
|
|
|
func (iface *tcpInterface) getAddr() *net.TCPAddr {
|
|
return iface.serv.Addr().(*net.TCPAddr)
|
|
}
|
|
|
|
func (iface *tcpInterface) connect(addr string) {
|
|
iface.call(addr)
|
|
}
|
|
|
|
func (iface *tcpInterface) connectSOCKS(socksaddr, peeraddr string) {
|
|
go func() {
|
|
dialer, err := proxy.SOCKS5("tcp", socksaddr, nil, proxy.Direct)
|
|
if err == nil {
|
|
conn, err := dialer.Dial("tcp", peeraddr)
|
|
if err == nil {
|
|
iface.callWithConn(&wrappedConn{
|
|
c: conn,
|
|
raddr: &wrappedAddr{
|
|
network: "tcp",
|
|
addr: peeraddr,
|
|
},
|
|
})
|
|
}
|
|
}
|
|
}()
|
|
}
|
|
|
|
func (iface *tcpInterface) init(core *Core, addr string) (err error) {
|
|
iface.core = core
|
|
|
|
iface.serv, err = net.Listen("tcp", addr)
|
|
if err == nil {
|
|
iface.calls = make(map[string]struct{})
|
|
iface.conns = make(map[tcpInfo](chan struct{}))
|
|
go iface.listener()
|
|
}
|
|
|
|
return err
|
|
}
|
|
|
|
func (iface *tcpInterface) listener() {
|
|
defer iface.serv.Close()
|
|
iface.core.log.Println("Listening for TCP on:", iface.serv.Addr().String())
|
|
for {
|
|
sock, err := iface.serv.Accept()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
go iface.handler(sock, true)
|
|
}
|
|
}
|
|
|
|
func (iface *tcpInterface) callWithConn(conn net.Conn) {
|
|
go func() {
|
|
raddr := conn.RemoteAddr().String()
|
|
iface.mutex.Lock()
|
|
_, isIn := iface.calls[raddr]
|
|
iface.mutex.Unlock()
|
|
if !isIn {
|
|
iface.mutex.Lock()
|
|
iface.calls[raddr] = struct{}{}
|
|
iface.mutex.Unlock()
|
|
defer func() {
|
|
iface.mutex.Lock()
|
|
delete(iface.calls, raddr)
|
|
iface.mutex.Unlock()
|
|
}()
|
|
iface.handler(conn, false)
|
|
}
|
|
}()
|
|
}
|
|
|
|
func (iface *tcpInterface) call(saddr string) {
|
|
go func() {
|
|
quit := false
|
|
iface.mutex.Lock()
|
|
if _, isIn := iface.calls[saddr]; isIn {
|
|
quit = true
|
|
} else {
|
|
iface.calls[saddr] = struct{}{}
|
|
defer func() {
|
|
iface.mutex.Lock()
|
|
delete(iface.calls, saddr)
|
|
iface.mutex.Unlock()
|
|
}()
|
|
}
|
|
iface.mutex.Unlock()
|
|
if !quit {
|
|
conn, err := net.Dial("tcp", saddr)
|
|
if err != nil {
|
|
return
|
|
}
|
|
iface.handler(conn, false)
|
|
}
|
|
}()
|
|
}
|
|
|
|
func (iface *tcpInterface) handler(sock net.Conn, incoming bool) {
|
|
defer sock.Close()
|
|
// Get our keys
|
|
keys := []byte{}
|
|
keys = append(keys, tcp_key[:]...)
|
|
keys = append(keys, iface.core.boxPub[:]...)
|
|
keys = append(keys, iface.core.sigPub[:]...)
|
|
_, err := sock.Write(keys)
|
|
if err != nil {
|
|
return
|
|
}
|
|
timeout := time.Now().Add(6 * time.Second)
|
|
sock.SetReadDeadline(timeout)
|
|
n, err := sock.Read(keys)
|
|
if err != nil {
|
|
return
|
|
}
|
|
if n < len(keys) { /*panic("Partial key packet?") ;*/
|
|
return
|
|
}
|
|
info := tcpInfo{}
|
|
if !tcp_chop_keys(&info.box, &info.sig, &keys) { /*panic("Invalid key packet?") ;*/
|
|
return
|
|
}
|
|
// Quit the parent call if this is a connection to ourself
|
|
equiv := func(k1, k2 []byte) bool {
|
|
for idx := range k1 {
|
|
if k1[idx] != k2[idx] {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
if equiv(info.box[:], iface.core.boxPub[:]) {
|
|
return
|
|
} // testing
|
|
if equiv(info.sig[:], iface.core.sigPub[:]) {
|
|
return
|
|
}
|
|
// Check if we're authorized to connect to this key / IP
|
|
if incoming && !iface.core.peers.isAllowedEncryptionPublicKey(&info.box) {
|
|
// Allow unauthorized peers if they're link-local
|
|
raddrStr, _, _ := net.SplitHostPort(sock.RemoteAddr().String())
|
|
raddr := net.ParseIP(raddrStr)
|
|
if !raddr.IsLinkLocalUnicast() {
|
|
return
|
|
}
|
|
}
|
|
// Check if we already have a connection to this node, close and block if yes
|
|
info.localAddr, _, _ = net.SplitHostPort(sock.LocalAddr().String())
|
|
info.remoteAddr, _, _ = net.SplitHostPort(sock.RemoteAddr().String())
|
|
iface.mutex.Lock()
|
|
if blockChan, isIn := iface.conns[info]; isIn {
|
|
iface.mutex.Unlock()
|
|
sock.Close()
|
|
<-blockChan
|
|
return
|
|
}
|
|
blockChan := make(chan struct{})
|
|
iface.conns[info] = blockChan
|
|
iface.mutex.Unlock()
|
|
defer func() {
|
|
iface.mutex.Lock()
|
|
delete(iface.conns, info)
|
|
iface.mutex.Unlock()
|
|
close(blockChan)
|
|
}()
|
|
// Note that multiple connections to the same node are allowed
|
|
// E.g. over different interfaces
|
|
p := iface.core.peers.newPeer(&info.box, &info.sig)
|
|
p.linkOut = make(chan []byte, 1)
|
|
in := func(bs []byte) {
|
|
p.handlePacket(bs)
|
|
}
|
|
out := make(chan []byte, 32) // TODO? what size makes sense
|
|
defer close(out)
|
|
go func() {
|
|
var shadow uint64
|
|
var stack [][]byte
|
|
put := func(msg []byte) {
|
|
stack = append(stack, msg)
|
|
for len(stack) > 32 {
|
|
util_putBytes(stack[0])
|
|
stack = stack[1:]
|
|
shadow++
|
|
}
|
|
}
|
|
send := func(msg []byte) {
|
|
msgLen := wire_encode_uint64(uint64(len(msg)))
|
|
buf := net.Buffers{tcp_msg[:], msgLen, msg}
|
|
buf.WriteTo(sock)
|
|
util_putBytes(msg)
|
|
}
|
|
timerInterval := 4 * time.Second
|
|
timer := time.NewTimer(timerInterval)
|
|
defer timer.Stop()
|
|
for {
|
|
for ; shadow > 0; shadow-- {
|
|
p.updateQueueSize(-1)
|
|
}
|
|
timer.Stop()
|
|
select {
|
|
case <-timer.C:
|
|
default:
|
|
}
|
|
timer.Reset(timerInterval)
|
|
select {
|
|
case _ = <-timer.C:
|
|
//iface.core.log.Println("DEBUG: sending keep-alive:", sock.RemoteAddr().String())
|
|
send(nil) // TCP keep-alive traffic
|
|
case msg := <-p.linkOut:
|
|
send(msg)
|
|
case msg, ok := <-out:
|
|
if !ok {
|
|
return
|
|
}
|
|
put(msg)
|
|
}
|
|
for len(stack) > 0 {
|
|
select {
|
|
case msg := <-p.linkOut:
|
|
send(msg)
|
|
case msg, ok := <-out:
|
|
if !ok {
|
|
return
|
|
}
|
|
put(msg)
|
|
default:
|
|
msg := stack[len(stack)-1]
|
|
stack = stack[:len(stack)-1]
|
|
send(msg)
|
|
p.updateQueueSize(-1)
|
|
}
|
|
}
|
|
}
|
|
}()
|
|
p.out = func(msg []byte) {
|
|
defer func() { recover() }()
|
|
select {
|
|
case out <- msg:
|
|
p.updateQueueSize(1)
|
|
default:
|
|
util_putBytes(msg)
|
|
}
|
|
}
|
|
p.close = func() { sock.Close() }
|
|
setNoDelay(sock, true)
|
|
go p.linkLoop()
|
|
defer func() {
|
|
// Put all of our cleanup here...
|
|
p.core.peers.removePeer(p.port)
|
|
}()
|
|
them, _, _ := net.SplitHostPort(sock.RemoteAddr().String())
|
|
themNodeID := getNodeID(&info.box)
|
|
themAddr := address_addrForNodeID(themNodeID)
|
|
themAddrString := net.IP(themAddr[:]).String()
|
|
themString := fmt.Sprintf("%s@%s", themAddrString, them)
|
|
iface.core.log.Println("Connected:", themString)
|
|
iface.reader(sock, in) // In this goroutine, because of defers
|
|
iface.core.log.Println("Disconnected:", themString)
|
|
return
|
|
}
|
|
|
|
func (iface *tcpInterface) reader(sock net.Conn, in func([]byte)) {
|
|
bs := make([]byte, 2*tcp_msgSize)
|
|
frag := bs[:0]
|
|
for {
|
|
timeout := time.Now().Add(6 * time.Second)
|
|
sock.SetReadDeadline(timeout)
|
|
n, err := sock.Read(bs[len(frag):])
|
|
if err != nil || n == 0 {
|
|
// iface.core.log.Println(err)
|
|
break
|
|
}
|
|
frag = bs[:len(frag)+n]
|
|
for {
|
|
msg, ok, err := tcp_chop_msg(&frag)
|
|
if err != nil {
|
|
// iface.core.log.Println(err)
|
|
return
|
|
}
|
|
if !ok {
|
|
break
|
|
} // We didn't get the whole message yet
|
|
newMsg := append(util_getBytes(), msg...)
|
|
in(newMsg)
|
|
util_yield()
|
|
}
|
|
frag = append(bs[:0], frag...)
|
|
}
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
// Magic bytes to check
|
|
var tcp_key = [...]byte{'k', 'e', 'y', 's'}
|
|
var tcp_msg = [...]byte{0xde, 0xad, 0xb1, 0x75} // "dead bits"
|
|
|
|
func tcp_chop_keys(box *boxPubKey, sig *sigPubKey, bs *[]byte) bool {
|
|
// This one is pretty simple: we know how long the message should be
|
|
// So don't call this with a message that's too short
|
|
if len(*bs) < len(tcp_key)+len(*box)+len(*sig) {
|
|
return false
|
|
}
|
|
for idx := range tcp_key {
|
|
if (*bs)[idx] != tcp_key[idx] {
|
|
return false
|
|
}
|
|
}
|
|
(*bs) = (*bs)[len(tcp_key):]
|
|
copy(box[:], *bs)
|
|
(*bs) = (*bs)[len(box):]
|
|
copy(sig[:], *bs)
|
|
(*bs) = (*bs)[len(sig):]
|
|
return true
|
|
}
|
|
|
|
func tcp_chop_msg(bs *[]byte) ([]byte, bool, error) {
|
|
// Returns msg, ok, err
|
|
if len(*bs) < len(tcp_msg) {
|
|
return nil, false, nil
|
|
}
|
|
for idx := range tcp_msg {
|
|
if (*bs)[idx] != tcp_msg[idx] {
|
|
return nil, false, errors.New("Bad message!")
|
|
}
|
|
}
|
|
msgLen, msgLenLen := wire_decode_uint64((*bs)[len(tcp_msg):])
|
|
if msgLen > tcp_msgSize {
|
|
return nil, false, errors.New("Oversized message!")
|
|
}
|
|
msgBegin := len(tcp_msg) + msgLenLen
|
|
msgEnd := msgBegin + int(msgLen)
|
|
if msgLenLen == 0 || len(*bs) < msgEnd {
|
|
// We don't have the full message
|
|
// Need to buffer this and wait for the rest to come in
|
|
return nil, false, nil
|
|
}
|
|
msg := (*bs)[msgBegin:msgEnd]
|
|
(*bs) = (*bs)[msgEnd:]
|
|
return msg, true, nil
|
|
}
|