mirror of
https://github.com/octoleo/syncthing.git
synced 2024-12-25 12:10:05 +00:00
82 lines
2.3 KiB
Go
82 lines
2.3 KiB
Go
|
// Copyright 2012 The Go Authors. All rights reserved.
|
||
|
|
// Use of this source code is governed by a BSD-style
|
||
|
|
// license that can be found in the LICENSE file.
|
||
|
|
|
||
|
|
// +build !plan9,!windows
|
||
|
|
|
||
|
|
package ipv4
|
||
|
|
|
||
|
|
import (
|
||
|
|
"net"
|
||
|
|
"syscall"
|
||
|
|
)
|
||
|
|
|
||
|
|
// ReadFrom reads a payload of the received IPv4 datagram, from the
|
||
|
|
// endpoint c, copying the payload into b. It returns the number of
|
||
|
|
// bytes copied into b, the control message cm and the source address
|
||
|
|
// src of the received datagram.
|
||
|
|
func (c *payloadHandler) ReadFrom(b []byte) (n int, cm *ControlMessage, src net.Addr, err error) {
|
||
|
|
if !c.ok() {
|
||
|
|
return 0, nil, nil, syscall.EINVAL
|
||
|
|
}
|
||
|
|
oob := newControlMessage(&c.rawOpt)
|
||
|
|
var oobn int
|
||
|
|
switch c := c.PacketConn.(type) {
|
||
|
|
case *net.UDPConn:
|
||
|
|
if n, oobn, _, src, err = c.ReadMsgUDP(b, oob); err != nil {
|
||
|
|
return 0, nil, nil, err
|
||
|
|
}
|
||
|
|
case *net.IPConn:
|
||
|
|
if sockOpts[ssoStripHeader].name > 0 {
|
||
|
|
if n, oobn, _, src, err = c.ReadMsgIP(b, oob); err != nil {
|
||
|
|
return 0, nil, nil, err
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
nb := make([]byte, maxHeaderLen+len(b))
|
||
|
|
if n, oobn, _, src, err = c.ReadMsgIP(nb, oob); err != nil {
|
||
|
|
return 0, nil, nil, err
|
||
|
|
}
|
||
|
|
hdrlen := int(nb[0]&0x0f) << 2
|
||
|
|
copy(b, nb[hdrlen:])
|
||
|
|
n -= hdrlen
|
||
|
|
}
|
||
|
|
default:
|
||
|
|
return 0, nil, nil, errInvalidConnType
|
||
|
|
}
|
||
|
|
if cm, err = parseControlMessage(oob[:oobn]); err != nil {
|
||
|
|
return 0, nil, nil, err
|
||
|
|
}
|
||
|
|
if cm != nil {
|
||
|
|
cm.Src = netAddrToIP4(src)
|
||
|
|
}
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
// WriteTo writes a payload of the IPv4 datagram, to the destination
|
||
|
|
// address dst through the endpoint c, copying the payload from b. It
|
||
|
|
// returns the number of bytes written. The control message cm allows
|
||
|
|
// the datagram path and the outgoing interface to be specified.
|
||
|
|
// Currently only Darwin and Linux support this. The cm may be nil if
|
||
|
|
// control of the outgoing datagram is not required.
|
||
|
|
func (c *payloadHandler) WriteTo(b []byte, cm *ControlMessage, dst net.Addr) (n int, err error) {
|
||
|
|
if !c.ok() {
|
||
|
|
return 0, syscall.EINVAL
|
||
|
|
}
|
||
|
|
oob := marshalControlMessage(cm)
|
||
|
|
if dst == nil {
|
||
|
|
return 0, errMissingAddress
|
||
|
|
}
|
||
|
|
switch c := c.PacketConn.(type) {
|
||
|
|
case *net.UDPConn:
|
||
|
|
n, _, err = c.WriteMsgUDP(b, oob, dst.(*net.UDPAddr))
|
||
|
|
case *net.IPConn:
|
||
|
|
n, _, err = c.WriteMsgIP(b, oob, dst.(*net.IPAddr))
|
||
|
|
default:
|
||
|
|
return 0, errInvalidConnType
|
||
|
|
}
|
||
|
|
if err != nil {
|
||
|
|
return 0, err
|
||
|
|
}
|
||
|
|
return
|
||
|
|
}
|