Update dependencies

vendor/tailscale.com/portlist/netstat.go

@@ -0,0 +1,132 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build darwin && !ios
+
+package portlist
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+
+	"go4.org/mem"
+)
+
+// parsePort returns the port number at the end of s following the last "." or
+// ":", whichever comes last. It returns -1 on a parse error or invalid number
+// and 0 if the port number was "*".
+//
+// This is basically net.SplitHostPort except that it handles a "." (as macOS
+// and others return in netstat output), uses mem.RO, and validates that the
+// port must be numeric and in the uint16 range.
+func parsePort(s mem.RO) int {
+	// a.b.c.d:1234 or [a:b:c:d]:1234
+	i1 := mem.LastIndexByte(s, ':')
+	// a.b.c.d.1234 or [a:b:c:d].1234
+	i2 := mem.LastIndexByte(s, '.')
+
+	i := i1
+	if i2 > i {
+		i = i2
+	}
+	if i < 0 {
+		// no match; weird
+		return -1
+	}
+
+	portstr := s.SliceFrom(i + 1)
+	if portstr.EqualString("*") {
+		return 0
+	}
+
+	port, err := mem.ParseUint(portstr, 10, 16)
+	if err != nil {
+		// invalid port; weird
+		return -1
+	}
+
+	return int(port)
+}
+
+func isLoopbackAddr(s mem.RO) bool {
+	return mem.HasPrefix(s, mem.S("127.")) ||
+		mem.HasPrefix(s, mem.S("[::1]:")) ||
+		mem.HasPrefix(s, mem.S("::1."))
+}
+
+// appendParsePortsNetstat appends to base listening ports
+// from "netstat" output, read from br. See TestParsePortsNetstat
+// for example input lines.
+//
+// This used to be a lowest common denominator parser for "netstat -na" format.
+// All of Linux, Windows, and macOS support -na and give similar-ish output
+// formats that we can parse without special detection logic.
+// Unfortunately, options to filter by proto or state are non-portable,
+// so we'll filter for ourselves.
+// Nowadays, though, we only use it for macOS as of 2022-11-04.
+func appendParsePortsNetstat(base []Port, br *bufio.Reader, includeLocalhost bool) ([]Port, error) {
+	ret := base
+	var fieldBuf [10]mem.RO
+	for {
+		line, err := br.ReadBytes('\n')
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return nil, err
+		}
+		trimline := bytes.TrimSpace(line)
+		cols := mem.AppendFields(fieldBuf[:0], mem.B(trimline))
+		if len(cols) < 1 {
+			continue
+		}
+		protos := cols[0]
+
+		var proto string
+		var laddr, raddr mem.RO
+		if mem.HasPrefixFold(protos, mem.S("tcp")) {
+			if len(cols) < 4 {
+				continue
+			}
+			proto = "tcp"
+			laddr = cols[len(cols)-3]
+			raddr = cols[len(cols)-2]
+			state := cols[len(cols)-1]
+			if !mem.HasPrefix(state, mem.S("LISTEN")) {
+				// not interested in non-listener sockets
+				continue
+			}
+			if !includeLocalhost && isLoopbackAddr(laddr) {
+				// not interested in loopback-bound listeners
+				continue
+			}
+		} else if mem.HasPrefixFold(protos, mem.S("udp")) {
+			if len(cols) < 3 {
+				continue
+			}
+			proto = "udp"
+			laddr = cols[len(cols)-2]
+			raddr = cols[len(cols)-1]
+			if !includeLocalhost && isLoopbackAddr(laddr) {
+				// not interested in loopback-bound listeners
+				continue
+			}
+		} else {
+			// not interested in other protocols
+			continue
+		}
+
+		lport := parsePort(laddr)
+		rport := parsePort(raddr)
+		if rport > 0 || lport <= 0 {
+			// not interested in "connected" sockets
+			continue
+		}
+		ret = append(ret, Port{
+			Proto: proto,
+			Port:  uint16(lport),
+		})
+	}
+	return ret, nil
+}