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Diffstat (limited to 'vendor/golang.org/x/net/ipv4/payload_cmsg.go')
-rw-r--r--vendor/golang.org/x/net/ipv4/payload_cmsg.go85
1 files changed, 85 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/ipv4/payload_cmsg.go b/vendor/golang.org/x/net/ipv4/payload_cmsg.go
new file mode 100644
index 0000000..1bb370e
--- /dev/null
+++ b/vendor/golang.org/x/net/ipv4/payload_cmsg.go
@@ -0,0 +1,85 @@
+// 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.
+
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || zos
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris zos
+
+package ipv4
+
+import (
+ "net"
+
+ "golang.org/x/net/internal/socket"
+)
+
+// 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, errInvalidConn
+ }
+ c.rawOpt.RLock()
+ m := socket.Message{
+ OOB: NewControlMessage(c.rawOpt.cflags),
+ }
+ c.rawOpt.RUnlock()
+ switch c.PacketConn.(type) {
+ case *net.UDPConn:
+ m.Buffers = [][]byte{b}
+ if err := c.RecvMsg(&m, 0); err != nil {
+ return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+ }
+ case *net.IPConn:
+ h := make([]byte, HeaderLen)
+ m.Buffers = [][]byte{h, b}
+ if err := c.RecvMsg(&m, 0); err != nil {
+ return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+ }
+ hdrlen := int(h[0]&0x0f) << 2
+ if hdrlen > len(h) {
+ d := hdrlen - len(h)
+ copy(b, b[d:])
+ m.N -= d
+ } else {
+ m.N -= hdrlen
+ }
+ default:
+ return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: errInvalidConnType}
+ }
+ if m.NN > 0 {
+ if compatFreeBSD32 {
+ adjustFreeBSD32(&m)
+ }
+ cm = new(ControlMessage)
+ if err := cm.Parse(m.OOB[:m.NN]); err != nil {
+ return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+ }
+ cm.Src = netAddrToIP4(m.Addr)
+ }
+ return m.N, cm, m.Addr, nil
+}
+
+// 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, errInvalidConn
+ }
+ m := socket.Message{
+ Buffers: [][]byte{b},
+ OOB: cm.Marshal(),
+ Addr: dst,
+ }
+ err = c.SendMsg(&m, 0)
+ if err != nil {
+ err = &net.OpError{Op: "write", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Addr: opAddr(dst), Err: err}
+ }
+ return m.N, err
+}