Update

vendor/tailscale.com/net/tsaddr/tsaddr.go

@@ -1,4 +1,4 @@
-// Copyright (c) Tailscale Inc & AUTHORS
+// Copyright (c) Tailscale Inc & contributors
 // SPDX-License-Identifier: BSD-3-Clause
 
 // Package tsaddr handles Tailscale-specific IPs and ranges.
@@ -7,6 +7,7 @@ package tsaddr
 import (
 	"encoding/binary"
 	"errors"
+	"iter"
 	"net/netip"
 	"slices"
 	"sync"
@@ -69,6 +70,7 @@ const (
 // IsTailscaleIP reports whether IP is an IP address in a range that
 // Tailscale assigns from.
 func IsTailscaleIP(ip netip.Addr) bool {
+	ip = ip.Unmap()
 	if ip.Is4() {
 		return IsTailscaleIPv4(ip)
 	}
@@ -77,6 +79,7 @@ func IsTailscaleIP(ip netip.Addr) bool {
 
 // IsTailscaleIPv4 reports whether an IPv4 IP is an IP address that
 // Tailscale assigns from.
+// It will always return false if ip is an "IPv4-mapped IPv6 address".
 func IsTailscaleIPv4(ip netip.Addr) bool {
 	return CGNATRange().Contains(ip) && !ChromeOSVMRange().Contains(ip)
 }
@@ -317,3 +320,24 @@ func MapVia(siteID uint32, v4 netip.Prefix) (via netip.Prefix, err error) {
 	copy(a[12:], ip4a[:])
 	return netip.PrefixFrom(netip.AddrFrom16(a), v4.Bits()+64+32), nil
 }
+
+// FirstTailscaleAddrs returns the first Tailscale IPv4 address and
+// the first Tailscale IPv6 address among the addresses of addrs'
+// prefixes, if any. The addrs sequence is typically a node's own
+// address list, either a slice (via [slices.All]) or a view (via
+// [views.Slice.All]).
+func FirstTailscaleAddrs(addrs iter.Seq2[int, netip.Prefix]) (a4, a6 netip.Addr) {
+	for _, pfx := range addrs {
+		a := pfx.Addr()
+		switch {
+		case a.Is4() && !a4.IsValid() && IsTailscaleIP(a):
+			a4 = a
+		case a.Is6() && !a6.IsValid() && IsTailscaleIP(a):
+			a6 = a
+		}
+		if a4.IsValid() && a6.IsValid() {
+			break
+		}
+	}
+	return a4, a6
+}