| // Copyright 2010 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. |
| |
| package net |
| |
| import ( |
| "context" |
| "syscall" |
| ) |
| |
| // BUG(mikio): On NaCl, Plan 9 and Windows, the ReadMsgIP and |
| // WriteMsgIP methods of IPConn are not implemented. |
| |
| // BUG(mikio): On Windows, the File method of IPConn is not |
| // implemented. |
| |
| // IPAddr represents the address of an IP end point. |
| type IPAddr struct { |
| IP IP |
| Zone string // IPv6 scoped addressing zone |
| } |
| |
| // Network returns the address's network name, "ip". |
| func (a *IPAddr) Network() string { return "ip" } |
| |
| func (a *IPAddr) String() string { |
| if a == nil { |
| return "<nil>" |
| } |
| ip := ipEmptyString(a.IP) |
| if a.Zone != "" { |
| return ip + "%" + a.Zone |
| } |
| return ip |
| } |
| |
| func (a *IPAddr) isWildcard() bool { |
| if a == nil || a.IP == nil { |
| return true |
| } |
| return a.IP.IsUnspecified() |
| } |
| |
| func (a *IPAddr) opAddr() Addr { |
| if a == nil { |
| return nil |
| } |
| return a |
| } |
| |
| // ResolveIPAddr parses addr as an IP address of the form "host" or |
| // "ipv6-host%zone" and resolves the domain name on the network net, |
| // which must be "ip", "ip4" or "ip6". |
| func ResolveIPAddr(net, addr string) (*IPAddr, error) { |
| if net == "" { // a hint wildcard for Go 1.0 undocumented behavior |
| net = "ip" |
| } |
| afnet, _, err := parseNetwork(context.Background(), net) |
| if err != nil { |
| return nil, err |
| } |
| switch afnet { |
| case "ip", "ip4", "ip6": |
| default: |
| return nil, UnknownNetworkError(net) |
| } |
| addrs, err := internetAddrList(context.Background(), afnet, addr) |
| if err != nil { |
| return nil, err |
| } |
| return addrs.first(isIPv4).(*IPAddr), nil |
| } |
| |
| // IPConn is the implementation of the Conn and PacketConn interfaces |
| // for IP network connections. |
| type IPConn struct { |
| conn |
| } |
| |
| // ReadFromIP reads an IP packet from c, copying the payload into b. |
| // It returns the number of bytes copied into b and the return address |
| // that was on the packet. |
| // |
| // ReadFromIP can be made to time out and return an error with |
| // Timeout() == true after a fixed time limit; see SetDeadline and |
| // SetReadDeadline. |
| func (c *IPConn) ReadFromIP(b []byte) (int, *IPAddr, error) { |
| if !c.ok() { |
| return 0, nil, syscall.EINVAL |
| } |
| n, addr, err := c.readFrom(b) |
| if err != nil { |
| err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err} |
| } |
| return n, addr, err |
| } |
| |
| // ReadFrom implements the PacketConn ReadFrom method. |
| func (c *IPConn) ReadFrom(b []byte) (int, Addr, error) { |
| if !c.ok() { |
| return 0, nil, syscall.EINVAL |
| } |
| n, addr, err := c.readFrom(b) |
| if err != nil { |
| err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err} |
| } |
| if addr == nil { |
| return n, nil, err |
| } |
| return n, addr, err |
| } |
| |
| // ReadMsgIP reads a packet from c, copying the payload into b and the |
| // associated out-of-band data into oob. It returns the number of |
| // bytes copied into b, the number of bytes copied into oob, the flags |
| // that were set on the packet and the source address of the packet. |
| func (c *IPConn) ReadMsgIP(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error) { |
| if !c.ok() { |
| return 0, 0, 0, nil, syscall.EINVAL |
| } |
| n, oobn, flags, addr, err = c.readMsg(b, oob) |
| if err != nil { |
| err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err} |
| } |
| return |
| } |
| |
| // WriteToIP writes an IP packet to addr via c, copying the payload |
| // from b. |
| // |
| // WriteToIP can be made to time out and return an error with |
| // Timeout() == true after a fixed time limit; see SetDeadline and |
| // SetWriteDeadline. On packet-oriented connections, write timeouts |
| // are rare. |
| func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (int, error) { |
| if !c.ok() { |
| return 0, syscall.EINVAL |
| } |
| n, err := c.writeTo(b, addr) |
| if err != nil { |
| err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err} |
| } |
| return n, err |
| } |
| |
| // WriteTo implements the PacketConn WriteTo method. |
| func (c *IPConn) WriteTo(b []byte, addr Addr) (int, error) { |
| if !c.ok() { |
| return 0, syscall.EINVAL |
| } |
| a, ok := addr.(*IPAddr) |
| if !ok { |
| return 0, &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr, Err: syscall.EINVAL} |
| } |
| n, err := c.writeTo(b, a) |
| if err != nil { |
| err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: a.opAddr(), Err: err} |
| } |
| return n, err |
| } |
| |
| // WriteMsgIP writes a packet to addr via c, copying the payload from |
| // b and the associated out-of-band data from oob. It returns the |
| // number of payload and out-of-band bytes written. |
| func (c *IPConn) WriteMsgIP(b, oob []byte, addr *IPAddr) (n, oobn int, err error) { |
| if !c.ok() { |
| return 0, 0, syscall.EINVAL |
| } |
| n, oobn, err = c.writeMsg(b, oob, addr) |
| if err != nil { |
| err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err} |
| } |
| return |
| } |
| |
| func newIPConn(fd *netFD) *IPConn { return &IPConn{conn{fd}} } |
| |
| // DialIP connects to the remote address raddr on the network protocol |
| // netProto, which must be "ip", "ip4", or "ip6" followed by a colon |
| // and a protocol number or name. |
| func DialIP(netProto string, laddr, raddr *IPAddr) (*IPConn, error) { |
| c, err := dialIP(context.Background(), netProto, laddr, raddr) |
| if err != nil { |
| return nil, &OpError{Op: "dial", Net: netProto, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err} |
| } |
| return c, nil |
| } |
| |
| // ListenIP listens for incoming IP packets addressed to the local |
| // address laddr. The returned connection's ReadFrom and WriteTo |
| // methods can be used to receive and send IP packets with per-packet |
| // addressing. |
| func ListenIP(netProto string, laddr *IPAddr) (*IPConn, error) { |
| c, err := listenIP(context.Background(), netProto, laddr) |
| if err != nil { |
| return nil, &OpError{Op: "listen", Net: netProto, Source: nil, Addr: laddr.opAddr(), Err: err} |
| } |
| return c, nil |
| } |