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mirror of https://github.com/cwinfo/yggdrasil-go.git synced 2024-11-26 10:41:40 +00:00

start migrating tunConn to the actor model

This commit is contained in:
Arceliar 2019-08-24 11:38:47 -05:00
parent b582c444f8
commit 4893a07696
3 changed files with 192 additions and 4 deletions

View File

@ -5,6 +5,7 @@ import (
"errors"
"time"
"github.com/Arceliar/phony"
"github.com/yggdrasil-network/yggdrasil-go/src/address"
"github.com/yggdrasil-network/yggdrasil-go/src/crypto"
"github.com/yggdrasil-network/yggdrasil-go/src/util"
@ -16,6 +17,7 @@ import (
const tunConnTimeout = 2 * time.Minute
type tunConn struct {
phony.Actor
tun *TunAdapter
conn *yggdrasil.Conn
addr address.Address
@ -45,6 +47,83 @@ func (s *tunConn) _close_nomutex() {
}()
}
func (s *tunConn) _read(bs []byte) (err error) {
select {
case <-s.stop:
err = errors.New("session was already closed")
util.PutBytes(bs)
return
default:
}
if len(bs) == 0 {
err = errors.New("read packet with 0 size")
util.PutBytes(bs)
return
}
ipv4 := len(bs) > 20 && bs[0]&0xf0 == 0x40
ipv6 := len(bs) > 40 && bs[0]&0xf0 == 0x60
isCGA := true
// Check source addresses
switch {
case ipv6 && bs[8] == 0x02 && bytes.Equal(s.addr[:16], bs[8:24]): // source
case ipv6 && bs[8] == 0x03 && bytes.Equal(s.snet[:8], bs[8:16]): // source
default:
isCGA = false
}
// Check destiantion addresses
switch {
case ipv6 && bs[24] == 0x02 && bytes.Equal(s.tun.addr[:16], bs[24:40]): // destination
case ipv6 && bs[24] == 0x03 && bytes.Equal(s.tun.subnet[:8], bs[24:32]): // destination
default:
isCGA = false
}
// Decide how to handle the packet
var skip bool
switch {
case isCGA: // Allowed
case s.tun.ckr.isEnabled() && (ipv4 || ipv6):
var srcAddr address.Address
var dstAddr address.Address
var addrlen int
if ipv4 {
copy(srcAddr[:], bs[12:16])
copy(dstAddr[:], bs[16:20])
addrlen = 4
}
if ipv6 {
copy(srcAddr[:], bs[8:24])
copy(dstAddr[:], bs[24:40])
addrlen = 16
}
if !s.tun.ckr.isValidLocalAddress(dstAddr, addrlen) {
// The destination address isn't in our CKR allowed range
skip = true
} else if key, err := s.tun.ckr.getPublicKeyForAddress(srcAddr, addrlen); err == nil {
srcNodeID := crypto.GetNodeID(&key)
if s.conn.RemoteAddr() == *srcNodeID {
// This is the one allowed CKR case, where source and destination addresses are both good
} else {
// The CKR key associated with this address doesn't match the sender's NodeID
skip = true
}
} else {
// We have no CKR route for this source address
skip = true
}
default:
skip = true
}
if skip {
err = errors.New("address not allowed")
util.PutBytes(bs)
return
}
// FIXME this send can block if the tuntap isn't running, which isn't really safe...
s.tun.send <- bs
s.stillAlive()
return
}
func (s *tunConn) reader() (err error) {
select {
case _, ok := <-s.stop:
@ -137,6 +216,110 @@ func (s *tunConn) reader() (err error) {
}
}
func (s *tunConn) _write(bs []byte) (err error) {
select {
case <-s.stop:
err = errors.New("session was already closed")
util.PutBytes(bs)
return
default:
}
v4 := len(bs) > 20 && bs[0]&0xf0 == 0x40
v6 := len(bs) > 40 && bs[0]&0xf0 == 0x60
isCGA := true
// Check source addresses
switch {
case v6 && bs[8] == 0x02 && bytes.Equal(s.tun.addr[:16], bs[8:24]): // source
case v6 && bs[8] == 0x03 && bytes.Equal(s.tun.subnet[:8], bs[8:16]): // source
default:
isCGA = false
}
// Check destiantion addresses
switch {
case v6 && bs[24] == 0x02 && bytes.Equal(s.addr[:16], bs[24:40]): // destination
case v6 && bs[24] == 0x03 && bytes.Equal(s.snet[:8], bs[24:32]): // destination
default:
isCGA = false
}
// Decide how to handle the packet
var skip bool
switch {
case isCGA: // Allowed
case s.tun.ckr.isEnabled() && (v4 || v6):
var srcAddr address.Address
var dstAddr address.Address
var addrlen int
if v4 {
copy(srcAddr[:], bs[12:16])
copy(dstAddr[:], bs[16:20])
addrlen = 4
}
if v6 {
copy(srcAddr[:], bs[8:24])
copy(dstAddr[:], bs[24:40])
addrlen = 16
}
if !s.tun.ckr.isValidLocalAddress(srcAddr, addrlen) {
// The source address isn't in our CKR allowed range
skip = true
} else if key, err := s.tun.ckr.getPublicKeyForAddress(dstAddr, addrlen); err == nil {
dstNodeID := crypto.GetNodeID(&key)
if s.conn.RemoteAddr() == *dstNodeID {
// This is the one allowed CKR case, where source and destination addresses are both good
} else {
// The CKR key associated with this address doesn't match the sender's NodeID
skip = true
}
} else {
// We have no CKR route for this destination address... why do we have the packet in the first place?
skip = true
}
default:
skip = true
}
if skip {
err = errors.New("address not allowed")
util.PutBytes(bs)
return
}
msg := yggdrasil.FlowKeyMessage{
FlowKey: util.GetFlowKey(bs),
Message: bs,
}
s.conn.WriteFrom(s, msg, func(err error) {
if err == nil {
// No point in wasting resources to send back an error if there was none
return
}
s.EnqueueFrom(s.conn, func() {
if e, eok := err.(yggdrasil.ConnError); !eok {
if e.Closed() {
s.tun.log.Debugln(s.conn.String(), "TUN/TAP generic write debug:", err)
} else {
s.tun.log.Errorln(s.conn.String(), "TUN/TAP generic write error:", err)
}
} else if e.PacketTooBig() {
// TODO: This currently isn't aware of IPv4 for CKR
ptb := &icmp.PacketTooBig{
MTU: int(e.PacketMaximumSize()),
Data: bs[:900],
}
if packet, err := CreateICMPv6(bs[8:24], bs[24:40], ipv6.ICMPTypePacketTooBig, 0, ptb); err == nil {
s.tun.send <- packet
}
} else {
if e.Closed() {
s.tun.log.Debugln(s.conn.String(), "TUN/TAP conn write debug:", err)
} else {
s.tun.log.Errorln(s.conn.String(), "TUN/TAP conn write error:", err)
}
}
})
})
s.stillAlive()
return
}
func (s *tunConn) writer() error {
select {
case _, ok := <-s.stop:

View File

@ -232,7 +232,7 @@ func (tun *TunAdapter) readerPacketHandler(ch chan []byte) {
if tc != nil {
for _, packet := range packets {
p := packet // Possibly required because of how range
tc.send <- p
<-tc.SyncExec(func() { tc._write(p) })
}
}
}()
@ -242,7 +242,7 @@ func (tun *TunAdapter) readerPacketHandler(ch chan []byte) {
}
// If we have a connection now, try writing to it
if isIn && session != nil {
session.send <- bs
<-session.SyncExec(func() { session._write(bs) })
}
}
}

View File

@ -257,8 +257,13 @@ func (tun *TunAdapter) wrap(conn *yggdrasil.Conn) (c *tunConn, err error) {
tun.addrToConn[s.addr] = &s
tun.subnetToConn[s.snet] = &s
// Start the connection goroutines
go s.reader()
go s.writer()
conn.SetReadCallback(func(bs []byte) {
s.EnqueueFrom(conn, func() {
s._read(bs)
})
})
//go s.reader()
//go s.writer()
go s.checkForTimeouts()
// Return
return c, err