// 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. //go:build unix || js || wasip1 || windows package net import ( "context" "syscall" ) func sockaddrToIP(sa syscall.Sockaddr) Addr { switch sa := sa.(type) { case *syscall.SockaddrInet4: return &IPAddr{IP: sa.Addr[0:]} case *syscall.SockaddrInet6: return &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))} } return nil } func (a *IPAddr) family() int { if a == nil || len(a.IP) <= IPv4len { return syscall.AF_INET } if a.IP.To4() != nil { return syscall.AF_INET } return syscall.AF_INET6 } func (a *IPAddr) sockaddr(family int) (syscall.Sockaddr, error) { if a == nil { return nil, nil } return ipToSockaddr(family, a.IP, 0, a.Zone) } func (a *IPAddr) toLocal(net string) sockaddr { return &IPAddr{loopbackIP(net), a.Zone} } func (c *IPConn) readFrom(b []byte) (int, *IPAddr, error) { // TODO(cw,rsc): consider using readv if we know the family // type to avoid the header trim/copy var addr *IPAddr n, sa, err := c.fd.readFrom(b) switch sa := sa.(type) { case *syscall.SockaddrInet4: addr = &IPAddr{IP: sa.Addr[0:]} n = stripIPv4Header(n, b) case *syscall.SockaddrInet6: addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))} } return n, addr, err } func stripIPv4Header(n int, b []byte) int { if len(b) < 20 { return n } l := int(b[0]&0x0f) << 2 if 20 > l || l > len(b) { return n } if b[0]>>4 != 4 { return n } copy(b, b[l:]) return n - l } func (c *IPConn) readMsg(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error) { var sa syscall.Sockaddr n, oobn, flags, sa, err = c.fd.readMsg(b, oob, 0) switch sa := sa.(type) { case *syscall.SockaddrInet4: addr = &IPAddr{IP: sa.Addr[0:]} case *syscall.SockaddrInet6: addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))} } return } func (c *IPConn) writeTo(b []byte, addr *IPAddr) (int, error) { if c.fd.isConnected { return 0, ErrWriteToConnected } if addr == nil { return 0, errMissingAddress } sa, err := addr.sockaddr(c.fd.family) if err != nil { return 0, err } return c.fd.writeTo(b, sa) } func (c *IPConn) writeMsg(b, oob []byte, addr *IPAddr) (n, oobn int, err error) { if c.fd.isConnected { return 0, 0, ErrWriteToConnected } if addr == nil { return 0, 0, errMissingAddress } sa, err := addr.sockaddr(c.fd.family) if err != nil { return 0, 0, err } return c.fd.writeMsg(b, oob, sa) } func (sd *sysDialer) dialIP(ctx context.Context, laddr, raddr *IPAddr) (*IPConn, error) { network, proto, err := parseNetwork(ctx, sd.network, true) if err != nil { return nil, err } switch network { case "ip", "ip4", "ip6": default: return nil, UnknownNetworkError(sd.network) } ctrlCtxFn := sd.Dialer.ControlContext if ctrlCtxFn == nil && sd.Dialer.Control != nil { ctrlCtxFn = func(cxt context.Context, network, address string, c syscall.RawConn) error { return sd.Dialer.Control(network, address, c) } } fd, err := internetSocket(ctx, network, laddr, raddr, syscall.SOCK_RAW, proto, "dial", ctrlCtxFn) if err != nil { return nil, err } return newIPConn(fd), nil } func (sl *sysListener) listenIP(ctx context.Context, laddr *IPAddr) (*IPConn, error) { network, proto, err := parseNetwork(ctx, sl.network, true) if err != nil { return nil, err } switch network { case "ip", "ip4", "ip6": default: return nil, UnknownNetworkError(sl.network) } var ctrlCtxFn func(cxt context.Context, network, address string, c syscall.RawConn) error if sl.ListenConfig.Control != nil { ctrlCtxFn = func(cxt context.Context, network, address string, c syscall.RawConn) error { return sl.ListenConfig.Control(network, address, c) } } fd, err := internetSocket(ctx, network, laddr, nil, syscall.SOCK_RAW, proto, "listen", ctrlCtxFn) if err != nil { return nil, err } return newIPConn(fd), nil }