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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:25:22 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:25:22 +0000 |
commit | f6ad4dcef54c5ce997a4bad5a6d86de229015700 (patch) | |
tree | 7cfa4e31ace5c2bd95c72b154d15af494b2bcbef /src/net/udpsock_plan9.go | |
parent | Initial commit. (diff) | |
download | golang-1.22-f6ad4dcef54c5ce997a4bad5a6d86de229015700.tar.xz golang-1.22-f6ad4dcef54c5ce997a4bad5a6d86de229015700.zip |
Adding upstream version 1.22.1.upstream/1.22.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/net/udpsock_plan9.go')
-rw-r--r-- | src/net/udpsock_plan9.go | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/src/net/udpsock_plan9.go b/src/net/udpsock_plan9.go new file mode 100644 index 0000000..732a3b0 --- /dev/null +++ b/src/net/udpsock_plan9.go @@ -0,0 +1,182 @@ +// Copyright 2009 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" + "errors" + "net/netip" + "os" + "syscall" +) + +func (c *UDPConn) readFrom(b []byte, addr *UDPAddr) (int, *UDPAddr, error) { + buf := make([]byte, udpHeaderSize+len(b)) + m, err := c.fd.Read(buf) + if err != nil { + return 0, nil, err + } + if m < udpHeaderSize { + return 0, nil, errors.New("short read reading UDP header") + } + buf = buf[:m] + + h, buf := unmarshalUDPHeader(buf) + n := copy(b, buf) + *addr = UDPAddr{IP: h.raddr, Port: int(h.rport)} + return n, addr, nil +} + +func (c *UDPConn) readFromAddrPort(b []byte) (int, netip.AddrPort, error) { + // TODO: optimize. The equivalent code on posix is alloc-free. + buf := make([]byte, udpHeaderSize+len(b)) + m, err := c.fd.Read(buf) + if err != nil { + return 0, netip.AddrPort{}, err + } + if m < udpHeaderSize { + return 0, netip.AddrPort{}, errors.New("short read reading UDP header") + } + buf = buf[:m] + + h, buf := unmarshalUDPHeader(buf) + n := copy(b, buf) + ip, _ := netip.AddrFromSlice(h.raddr) + addr := netip.AddrPortFrom(ip, h.rport) + return n, addr, nil +} + +func (c *UDPConn) readMsg(b, oob []byte) (n, oobn, flags int, addr netip.AddrPort, err error) { + return 0, 0, 0, netip.AddrPort{}, syscall.EPLAN9 +} + +func (c *UDPConn) writeTo(b []byte, addr *UDPAddr) (int, error) { + if addr == nil { + return 0, errMissingAddress + } + h := new(udpHeader) + h.raddr = addr.IP.To16() + h.laddr = c.fd.laddr.(*UDPAddr).IP.To16() + h.ifcaddr = IPv6zero // ignored (receive only) + h.rport = uint16(addr.Port) + h.lport = uint16(c.fd.laddr.(*UDPAddr).Port) + + buf := make([]byte, udpHeaderSize+len(b)) + i := copy(buf, h.Bytes()) + copy(buf[i:], b) + if _, err := c.fd.Write(buf); err != nil { + return 0, err + } + return len(b), nil +} + +func (c *UDPConn) writeToAddrPort(b []byte, addr netip.AddrPort) (int, error) { + return c.writeTo(b, UDPAddrFromAddrPort(addr)) // TODO: optimize instead of allocating +} + +func (c *UDPConn) writeMsg(b, oob []byte, addr *UDPAddr) (n, oobn int, err error) { + return 0, 0, syscall.EPLAN9 +} + +func (c *UDPConn) writeMsgAddrPort(b, oob []byte, addr netip.AddrPort) (n, oobn int, err error) { + return 0, 0, syscall.EPLAN9 +} + +func (sd *sysDialer) dialUDP(ctx context.Context, laddr, raddr *UDPAddr) (*UDPConn, error) { + fd, err := dialPlan9(ctx, sd.network, laddr, raddr) + if err != nil { + return nil, err + } + return newUDPConn(fd), nil +} + +const udpHeaderSize = 16*3 + 2*2 + +type udpHeader struct { + raddr, laddr, ifcaddr IP + rport, lport uint16 +} + +func (h *udpHeader) Bytes() []byte { + b := make([]byte, udpHeaderSize) + i := 0 + i += copy(b[i:i+16], h.raddr) + i += copy(b[i:i+16], h.laddr) + i += copy(b[i:i+16], h.ifcaddr) + b[i], b[i+1], i = byte(h.rport>>8), byte(h.rport), i+2 + b[i], b[i+1], i = byte(h.lport>>8), byte(h.lport), i+2 + return b +} + +func unmarshalUDPHeader(b []byte) (*udpHeader, []byte) { + h := new(udpHeader) + h.raddr, b = IP(b[:16]), b[16:] + h.laddr, b = IP(b[:16]), b[16:] + h.ifcaddr, b = IP(b[:16]), b[16:] + h.rport, b = uint16(b[0])<<8|uint16(b[1]), b[2:] + h.lport, b = uint16(b[0])<<8|uint16(b[1]), b[2:] + return h, b +} + +func (sl *sysListener) listenUDP(ctx context.Context, laddr *UDPAddr) (*UDPConn, error) { + l, err := listenPlan9(ctx, sl.network, laddr) + if err != nil { + return nil, err + } + _, err = l.ctl.WriteString("headers") + if err != nil { + return nil, err + } + l.data, err = os.OpenFile(l.dir+"/data", os.O_RDWR, 0) + if err != nil { + return nil, err + } + fd, err := l.netFD() + return newUDPConn(fd), err +} + +func (sl *sysListener) listenMulticastUDP(ctx context.Context, ifi *Interface, gaddr *UDPAddr) (*UDPConn, error) { + // Plan 9 does not like announce command with a multicast address, + // so do not specify an IP address when listening. + l, err := listenPlan9(ctx, sl.network, &UDPAddr{IP: nil, Port: gaddr.Port, Zone: gaddr.Zone}) + if err != nil { + return nil, err + } + _, err = l.ctl.WriteString("headers") + if err != nil { + return nil, err + } + var addrs []Addr + if ifi != nil { + addrs, err = ifi.Addrs() + if err != nil { + return nil, err + } + } else { + addrs, err = InterfaceAddrs() + if err != nil { + return nil, err + } + } + + have4 := gaddr.IP.To4() != nil + for _, addr := range addrs { + if ipnet, ok := addr.(*IPNet); ok && (ipnet.IP.To4() != nil) == have4 { + _, err = l.ctl.WriteString("addmulti " + ipnet.IP.String() + " " + gaddr.IP.String()) + if err != nil { + return nil, &OpError{Op: "addmulti", Net: "", Source: nil, Addr: ipnet, Err: err} + } + } + } + l.data, err = os.OpenFile(l.dir+"/data", os.O_RDWR, 0) + if err != nil { + return nil, err + } + fd, err := l.netFD() + if err != nil { + return nil, err + } + return newUDPConn(fd), nil +} |