feat: 动态同步 IPv6 前缀到 nftables

tests/test_fw_ipv6_prefix.sh

@@ -0,0 +1,83 @@
+#!/bin/sh
+set -eu
+
+ROOT=$(cd "$(dirname "$0")/.." && pwd)
+. "$ROOT/scripts/starts/fw_getlanip.sh"
+
+assert_equal() {
+    if [ "$1" != "$2" ]; then
+        echo "expected: [$1]" >&2
+        echo "actual:   [$2]" >&2
+        exit 1
+    fi
+}
+
+route_output='default via fe80::1 dev eth0
+default from 240e:1234:5600::/56 via fe80::1 dev pppoe-wan
+2408:8266:501:2443::/64 dev enp2s0 proto kernel
+2606:4700::/48 via fe80::2 dev eth0
+unreachable 240e:1234:5600::/48 dev lo'
+actual=$(printf '%s\n' "$route_output" | ipv6_route_prefixes | sort -u)
+expected='2408:8266:501:2443::/64
+240e:1234:5600::/56'
+assert_equal "$expected" "$actual"
+
+# OpenWrt prefers the LAN assignment over the wider delegated prefix.
+systype=mi_snapshot
+lan_ifaces='br-lan'
+ubus() {
+    printf '%s\n' '{ "l3_device": "br-lan" }'
+}
+ip() {
+    case "$*" in
+    '-6 route show dev br-lan')
+        echo 'default from 240e:1234:5600::/56 via fe80::1 dev br-lan'
+        echo '240e:1234:5600:1::/64 dev br-lan proto static'
+        ;;
+    '-6 route show default') echo 'default from 240e:1234:5600::/56 via fe80::1 dev pppoe-wan' ;;
+    esac
+}
+actual=$(get_ipv6_prefixes)
+assert_equal '240e:1234:5600:1::/64' "$actual"
+
+# OpenWrt falls back to source-specific routes when its LAN route is hidden.
+lan_ifaces=
+ubus() {
+    return 0
+}
+ip() {
+    case "$*" in
+    '-6 route show default') echo 'default from 240e:1234:5600::/56 via fe80::1 dev pppoe-wan' ;;
+    esac
+}
+actual=$(get_ipv6_prefixes)
+assert_equal '240e:1234:5600::/56' "$actual"
+
+# Standard Linux uses the directly connected route on the discovered LAN.
+systype=container
+lan_ifaces='enp2s0'
+ip() {
+    case "$*" in
+    '-6 route show dev enp2s0') echo '2408:8266:501:2443::/64 dev enp2s0 proto kernel metric 256' ;;
+    esac
+}
+actual=$(get_ipv6_prefixes)
+assert_equal '2408:8266:501:2443::/64' "$actual"
+
+# BusyBox based router firmware does not need route protocol metadata.
+systype=Padavan
+lan_ifaces='br0'
+ip() {
+    case "$*" in
+    '-6 route show dev br0') echo '2001:db8:abcd:1::/64 dev br0 metric 256' ;;
+    esac
+}
+actual=$(get_ipv6_prefixes)
+assert_equal '2001:db8:abcd:1::/64' "$actual"
+
+ts_service=ON
+wg_service=OFF
+build_host_ipv6 '2408:8266:501:2443::/64 invalid-value'
+assert_equal '2408:8266:501:2443::/64 fd00::/8 fd7a:115c:a1e0::/48 fe80::/10' "$host_ipv6"
+
+echo 'IPv6 prefix tests passed'