fix(admin): 登录审计记录真实来源 IP(经本机反代时取 XFF 末跳)

管理后台经 caddy mTLS 网关(同机 loopback 反代 127.0.0.1:9444)对外后, LoginSubmit 里 hostOnly(r.RemoteAddr) 恒为 127.0.0.1,admin_login_ok/fail 的 ip 字段失去溯源价值。新增 realIP():仅当 TCP 对端是 loopback(请求确实来自本机可信反代)才信 X-Forwarded-For,且取**最后一跳**(Caddy 把真实 TCP 对端追加在末位,更早的段可被客户端伪造预置);直连、XFF 缺失或非法值一律回退 TCP 对端。 IPAllow 白名单中间件刻意不变——安全闸继续只看 RemoteAddr,不受任何代理头影响(维持原注释声明的边界)。测试:TestRealIP 七例(直连/伪造头/单跳/多跳/缺失/非法/IPv6); go test ./internal/admin 全绿。(internal/store 迁移彩排 3 例失败为 HEAD 既有——主仓干净树复现,与本次无关。) Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01P9G7E3wmAYL9KeYCVZVsqu
2026-07-24 08:34:57 +08:00
parent dd721fafc8
commit f819a77d83
3 changed files with 64 additions and 1 deletions
@@ -0,0 +1,37 @@
+package admin
+
+import (
+	"net/http/httptest"
+	"testing"
+)
+
+// realIP:仅当 TCP 对端为 loopback(本机可信反代,如 caddy mTLS 网关)时才信
+// X-Forwarded-For 的最后一跳;其余情况一律用 TCP 对端,防止伪造头污染审计。
+func TestRealIP(t *testing.T) {
+	cases := []struct {
+		name       string
+		remoteAddr string
+		xff        string
+		want       string
+	}{
+		{"直连无代理", "203.0.113.7:52011", "", "203.0.113.7"},
+		{"直连时伪造 XFF 不可信", "203.0.113.7:52011", "1.2.3.4", "203.0.113.7"},
+		{"经本机反代取 XFF 最后一跳", "127.0.0.1:38200", "198.51.100.23", "198.51.100.23"},
+		{"多跳取最后一跳(前段可伪造)", "127.0.0.1:38200", "6.6.6.6, 198.51.100.23", "198.51.100.23"},
+		{"本机反代但无 XFF 回退 loopback", "127.0.0.1:38200", "", "127.0.0.1"},
+		{"XFF 非法值回退", "127.0.0.1:38200", "not-an-ip", "127.0.0.1"},
+		{"IPv6 loopback 反代", "[::1]:38200", "198.51.100.23", "198.51.100.23"},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			r := httptest.NewRequest("POST", "/login", nil)
+			r.RemoteAddr = c.remoteAddr
+			if c.xff != "" {
+				r.Header.Set("X-Forwarded-For", c.xff)
+			}
+			if got := realIP(r); got != c.want {
+				t.Errorf("realIP(remote=%s, xff=%q) = %q, want %q", c.remoteAddr, c.xff, got, c.want)
+			}
+		})
+	}
+}