Adding upstream version 1.20.14.upstream/1.20.14upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 367 insertions, 0 deletions

diff --git a/src/net/ipsock_plan9.go b/src/net/ipsock_plan9.go
new file mode 100644
index 0000000..4328743
--- /dev/null
+++ b/src/net/ipsock_plan9.go
@@ -0,0 +1,367 @@
+// 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"
+	"internal/bytealg"
+	"internal/itoa"
+	"io/fs"
+	"os"
+	"syscall"
+)
+
+// probe probes IPv4, IPv6 and IPv4-mapped IPv6 communication
+// capabilities.
+//
+// Plan 9 uses IPv6 natively, see ip(3).
+func (p *ipStackCapabilities) probe() {
+	p.ipv4Enabled = probe(netdir+"/iproute", "4i")
+	p.ipv6Enabled = probe(netdir+"/iproute", "6i")
+	if p.ipv4Enabled && p.ipv6Enabled {
+		p.ipv4MappedIPv6Enabled = true
+	}
+}
+
+func probe(filename, query string) bool {
+	var file *file
+	var err error
+	if file, err = open(filename); err != nil {
+		return false
+	}
+	defer file.close()
+
+	r := false
+	for line, ok := file.readLine(); ok && !r; line, ok = file.readLine() {
+		f := getFields(line)
+		if len(f) < 3 {
+			continue
+		}
+		for i := 0; i < len(f); i++ {
+			if query == f[i] {
+				r = true
+				break
+			}
+		}
+	}
+	return r
+}
+
+// parsePlan9Addr parses address of the form [ip!]port (e.g. 127.0.0.1!80).
+func parsePlan9Addr(s string) (ip IP, iport int, err error) {
+	addr := IPv4zero // address contains port only
+	i := bytealg.IndexByteString(s, '!')
+	if i >= 0 {
+		addr = ParseIP(s[:i])
+		if addr == nil {
+			return nil, 0, &ParseError{Type: "IP address", Text: s}
+		}
+	}
+	p, plen, ok := dtoi(s[i+1:])
+	if !ok {
+		return nil, 0, &ParseError{Type: "port", Text: s}
+	}
+	if p < 0 || p > 0xFFFF {
+		return nil, 0, &AddrError{Err: "invalid port", Addr: s[i+1 : i+1+plen]}
+	}
+	return addr, p, nil
+}
+
+func readPlan9Addr(net, filename string) (addr Addr, err error) {
+	var buf [128]byte
+
+	f, err := os.Open(filename)
+	if err != nil {
+		return
+	}
+	defer f.Close()
+	n, err := f.Read(buf[:])
+	if err != nil {
+		return
+	}
+	ip, port, err := parsePlan9Addr(string(buf[:n]))
+	if err != nil {
+		return
+	}
+	switch net {
+	case "tcp4", "udp4":
+		if ip.Equal(IPv6zero) {
+			ip = ip[:IPv4len]
+		}
+	}
+	switch net {
+	case "tcp", "tcp4", "tcp6":
+		addr = &TCPAddr{IP: ip, Port: port}
+	case "udp", "udp4", "udp6":
+		addr = &UDPAddr{IP: ip, Port: port}
+	default:
+		return nil, UnknownNetworkError(net)
+	}
+	return addr, nil
+}
+
+func startPlan9(ctx context.Context, net string, addr Addr) (ctl *os.File, dest, proto, name string, err error) {
+	var (
+		ip   IP
+		port int
+	)
+	switch a := addr.(type) {
+	case *TCPAddr:
+		proto = "tcp"
+		ip = a.IP
+		port = a.Port
+	case *UDPAddr:
+		proto = "udp"
+		ip = a.IP
+		port = a.Port
+	default:
+		err = UnknownNetworkError(net)
+		return
+	}
+
+	if port > 65535 {
+		err = InvalidAddrError("port should be < 65536")
+		return
+	}
+
+	clone, dest, err := queryCS1(ctx, proto, ip, port)
+	if err != nil {
+		return
+	}
+	f, err := os.OpenFile(clone, os.O_RDWR, 0)
+	if err != nil {
+		return
+	}
+	var buf [16]byte
+	n, err := f.Read(buf[:])
+	if err != nil {
+		f.Close()
+		return
+	}
+	return f, dest, proto, string(buf[:n]), nil
+}
+
+func fixErr(err error) {
+	oe, ok := err.(*OpError)
+	if !ok {
+		return
+	}
+	nonNilInterface := func(a Addr) bool {
+		switch a := a.(type) {
+		case *TCPAddr:
+			return a == nil
+		case *UDPAddr:
+			return a == nil
+		case *IPAddr:
+			return a == nil
+		default:
+			return false
+		}
+	}
+	if nonNilInterface(oe.Source) {
+		oe.Source = nil
+	}
+	if nonNilInterface(oe.Addr) {
+		oe.Addr = nil
+	}
+	if pe, ok := oe.Err.(*fs.PathError); ok {
+		if _, ok = pe.Err.(syscall.ErrorString); ok {
+			oe.Err = pe.Err
+		}
+	}
+}
+
+func dialPlan9(ctx context.Context, net string, laddr, raddr Addr) (fd *netFD, err error) {
+	defer func() { fixErr(err) }()
+	type res struct {
+		fd  *netFD
+		err error
+	}
+	resc := make(chan res)
+	go func() {
+		testHookDialChannel()
+		fd, err := dialPlan9Blocking(ctx, net, laddr, raddr)
+		select {
+		case resc <- res{fd, err}:
+		case <-ctx.Done():
+			if fd != nil {
+				fd.Close()
+			}
+		}
+	}()
+	select {
+	case res := <-resc:
+		return res.fd, res.err
+	case <-ctx.Done():
+		return nil, mapErr(ctx.Err())
+	}
+}
+
+func dialPlan9Blocking(ctx context.Context, net string, laddr, raddr Addr) (fd *netFD, err error) {
+	if isWildcard(raddr) {
+		raddr = toLocal(raddr, net)
+	}
+	f, dest, proto, name, err := startPlan9(ctx, net, raddr)
+	if err != nil {
+		return nil, err
+	}
+	if la := plan9LocalAddr(laddr); la == "" {
+		err = hangupCtlWrite(ctx, proto, f, "connect "+dest)
+	} else {
+		err = hangupCtlWrite(ctx, proto, f, "connect "+dest+" "+la)
+	}
+	if err != nil {
+		f.Close()
+		return nil, err
+	}
+	data, err := os.OpenFile(netdir+"/"+proto+"/"+name+"/data", os.O_RDWR, 0)
+	if err != nil {
+		f.Close()
+		return nil, err
+	}
+	laddr, err = readPlan9Addr(net, netdir+"/"+proto+"/"+name+"/local")
+	if err != nil {
+		data.Close()
+		f.Close()
+		return nil, err
+	}
+	return newFD(proto, name, nil, f, data, laddr, raddr)
+}
+
+func listenPlan9(ctx context.Context, net string, laddr Addr) (fd *netFD, err error) {
+	defer func() { fixErr(err) }()
+	f, dest, proto, name, err := startPlan9(ctx, net, laddr)
+	if err != nil {
+		return nil, err
+	}
+	_, err = f.WriteString("announce " + dest)
+	if err != nil {
+		f.Close()
+		return nil, &OpError{Op: "announce", Net: net, Source: laddr, Addr: nil, Err: err}
+	}
+	laddr, err = readPlan9Addr(net, netdir+"/"+proto+"/"+name+"/local")
+	if err != nil {
+		f.Close()
+		return nil, err
+	}
+	return newFD(proto, name, nil, f, nil, laddr, nil)
+}
+
+func (fd *netFD) netFD() (*netFD, error) {
+	return newFD(fd.net, fd.n, fd.listen, fd.ctl, fd.data, fd.laddr, fd.raddr)
+}
+
+func (fd *netFD) acceptPlan9() (nfd *netFD, err error) {
+	defer func() { fixErr(err) }()
+	if err := fd.pfd.ReadLock(); err != nil {
+		return nil, err
+	}
+	defer fd.pfd.ReadUnlock()
+	listen, err := os.Open(fd.dir + "/listen")
+	if err != nil {
+		return nil, err
+	}
+	var buf [16]byte
+	n, err := listen.Read(buf[:])
+	if err != nil {
+		listen.Close()
+		return nil, err
+	}
+	name := string(buf[:n])
+	ctl, err := os.OpenFile(netdir+"/"+fd.net+"/"+name+"/ctl", os.O_RDWR, 0)
+	if err != nil {
+		listen.Close()
+		return nil, err
+	}
+	data, err := os.OpenFile(netdir+"/"+fd.net+"/"+name+"/data", os.O_RDWR, 0)
+	if err != nil {
+		listen.Close()
+		ctl.Close()
+		return nil, err
+	}
+	raddr, err := readPlan9Addr(fd.net, netdir+"/"+fd.net+"/"+name+"/remote")
+	if err != nil {
+		listen.Close()
+		ctl.Close()
+		data.Close()
+		return nil, err
+	}
+	return newFD(fd.net, name, listen, ctl, data, fd.laddr, raddr)
+}
+
+func isWildcard(a Addr) bool {
+	var wildcard bool
+	switch a := a.(type) {
+	case *TCPAddr:
+		wildcard = a.isWildcard()
+	case *UDPAddr:
+		wildcard = a.isWildcard()
+	case *IPAddr:
+		wildcard = a.isWildcard()
+	}
+	return wildcard
+}
+
+func toLocal(a Addr, net string) Addr {
+	switch a := a.(type) {
+	case *TCPAddr:
+		a.IP = loopbackIP(net)
+	case *UDPAddr:
+		a.IP = loopbackIP(net)
+	case *IPAddr:
+		a.IP = loopbackIP(net)
+	}
+	return a
+}
+
+// plan9LocalAddr returns a Plan 9 local address string.
+// See setladdrport at https://9p.io/sources/plan9/sys/src/9/ip/devip.c.
+func plan9LocalAddr(addr Addr) string {
+	var ip IP
+	port := 0
+	switch a := addr.(type) {
+	case *TCPAddr:
+		if a != nil {
+			ip = a.IP
+			port = a.Port
+		}
+	case *UDPAddr:
+		if a != nil {
+			ip = a.IP
+			port = a.Port
+		}
+	}
+	if len(ip) == 0 || ip.IsUnspecified() {
+		if port == 0 {
+			return ""
+		}
+		return itoa.Itoa(port)
+	}
+	return ip.String() + "!" + itoa.Itoa(port)
+}
+
+func hangupCtlWrite(ctx context.Context, proto string, ctl *os.File, msg string) error {
+	if proto != "tcp" {
+		_, err := ctl.WriteString(msg)
+		return err
+	}
+	written := make(chan struct{})
+	errc := make(chan error)
+	go func() {
+		select {
+		case <-ctx.Done():
+			ctl.WriteString("hangup")
+			errc <- mapErr(ctx.Err())
+		case <-written:
+			errc <- nil
+		}
+	}()
+	_, err := ctl.WriteString(msg)
+	close(written)
+	if e := <-errc; err == nil && e != nil { // we hung up
+		return e
+	}
+	return err
+}