diff options
Diffstat (limited to 'vendor/golang.org/x/net/ipv4/payload_cmsg.go')
-rw-r--r-- | vendor/golang.org/x/net/ipv4/payload_cmsg.go | 85 |
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 +} |