feat(admin): 后台登录支持「记住此设备」(免二次验证 + 保持登录)

常用设备(已在 mTLS 白名单内)每次都要输 TOTP + 30 分钟就掉线,体验差。
新增登录页「记住此设备」勾选:

- 勾选并成功登录(需完整 密码+TOTP)后,签发 30 天设备信任令牌(HttpOnly/
  Secure/SameSite=Strict cookie,Redis 存储绑定 admin ID),并把会话延到 30 天
  (持久 cookie + 服务端 TTL,滑动续期按会话自身 TTL)。
- 之后该设备重登只需 用户名+密码,**跳过 TOTP**;会话在有效期内保持登录。

安全不变量(均有测试覆盖):
- 密码永远必验——即便持有效信任令牌,密码错一律拒(只跳过第二因子,不跳过密码);
- 信任令牌绑定 admin,alice 的令牌不能给 bob 免 TOTP;
- 无令牌 + 空 TOTP 一律拒(未记住设备仍强制二次验证);
- 令牌过期/Redis 清空/未知令牌全部 fail-closed 回退到「要 TOTP」;
- TrustedDeviceTTL=0 关闭整功能(勾选无效)。

实现:新增 TrustedStore(Redis, trusted.go);Authenticator.LoginDevice
(旧 Login 保持签名,委托新方法,零行为变化);SessionStore.CreateWithTTL +
Session.TTLSeconds 支持持久会话按自身 TTL 滑动;handler 读 cookie/勾选、
按 Persistent 设长短会话 cookie、下发信任 cookie;登录页加勾选、TOTP 去
required。配置项 ADMIN_TRUSTED_DEVICE_TTL(默认 720h)。

测试:trusted_test(签发/校验/绑定/吊销/过期/禁用)、login_device_test
(跳过TOTP/仍需密码/绑定admin/无令牌需TOTP)、login_device_handler_test
(端到端 勾选→双cookie→凭信任cookie免TOTP、无信任空TOTP 401);
go test ./internal/admin 全绿,go vet 净。

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01P9G7E3wmAYL9KeYCVZVsqu

server/internal/admin/auth.go

@@ -31,11 +31,14 @@ type Authenticator struct {
 	failMax  int
 	lockDur  time.Duration
 	sec      *SecurityLog
+	trusted  *TrustedStore
+	trustTTL time.Duration
 	// now is overridable in tests.
 	now func() time.Time
 }
 
-// NewAuthenticator wires an Authenticator.
+// NewAuthenticator wires an Authenticator. Device-trust ("记住此设备") is
+// enabled when cfg.TrustedDeviceTTL > 0.
 func NewAuthenticator(store Store, sessions *SessionStore, rdb *redis.Client, cfg *Config, sec *SecurityLog) *Authenticator {
 	return &Authenticator{
 		store:    store,
@@ -45,58 +48,105 @@ func NewAuthenticator(store Store, sessions *SessionStore, rdb *redis.Client, cf
 		failMax:  cfg.LoginFailMax,
 		lockDur:  cfg.LoginLockDuration,
 		sec:      sec,
+		trusted:  NewTrustedStore(rdb, cfg.TrustedDeviceTTL),
+		trustTTL: cfg.TrustedDeviceTTL,
 		now:      func() time.Time { return time.Now().UTC() },
 	}
 }
 
+// LoginResult is the outcome of a device-aware login.
+type LoginResult struct {
+	SID     string
+	Session *Session
+	// NewTrustToken is non-empty when the caller ticked "记住此设备" and a fresh
+	// device-trust token was issued — the handler sets it as the trust cookie.
+	NewTrustToken string
+	// Persistent is true when this login should use a long-lived (trust-TTL)
+	// session + cookie instead of the short idle default.
+	Persistent bool
+}
+
 // Login validates username + password + TOTP and, on success, creates a
 // session and returns its id. Every failure is rate-limited and recorded as a
 // security event in the audit log (red line: admin records only security
 // events, never routine access).
 func (a *Authenticator) Login(ctx context.Context, username, password, code, remoteIP string) (sid string, sess *Session, err error) {
+	res, lerr := a.LoginDevice(ctx, username, password, code, remoteIP, "", false)
+	return res.SID, res.Session, lerr
+}
+
+// LoginDevice is the device-aware login: username + password are ALWAYS
+// required; the TOTP second factor is skipped only when trustToken is a live
+// trust token bound to this admin ("记住此设备"). When remember is set, a fresh
+// trust token is issued and the session is made persistent (trust-TTL long).
+//
+// Security invariant: a trust token never substitutes for the password — a
+// wrong password fails regardless of trust.
+func (a *Authenticator) LoginDevice(ctx context.Context, username, password, code, remoteIP, trustToken string, remember bool) (LoginResult, error) {
 	locked, lerr := a.isLocked(ctx, username)
 	if lerr != nil {
-		return "", nil, fmt.Errorf("admin.Login lock check: %w", lerr)
+		return LoginResult{}, fmt.Errorf("admin.Login lock check: %w", lerr)
 	}
 	if locked {
 		a.sec.LoginLocked(ctx, username, remoteIP)
-		return "", nil, ErrLockedOut
+		return LoginResult{}, ErrLockedOut
 	}
 
 	admin, gerr := a.store.GetAdminByUsername(ctx, username)
 	if gerr != nil && !errors.Is(gerr, ErrAdminNotFound) {
-		return "", nil, fmt.Errorf("admin.Login lookup: %w", gerr)
+		return LoginResult{}, fmt.Errorf("admin.Login lookup: %w", gerr)
 	}
 
 	if admin == nil || admin.Status != "active" || !VerifyPassword(admin.PwHash, password) {
 		a.recordFail(ctx, username)
 		a.sec.LoginFail(ctx, username, remoteIP, "bad_password")
-		return "", nil, ErrInvalidCredentials
+		return LoginResult{}, ErrInvalidCredentials
 	}
 
-	secret, derr := DecryptSecret(a.secret, admin.TOTPSecretEnc)
-	if derr != nil {
-		a.recordFail(ctx, username)
-		a.sec.LoginFail(ctx, username, remoteIP, "totp_decrypt")
-		return "", nil, ErrInvalidCredentials
-	}
-	if !totp.Validate(secret, code, a.now(), 1) {
-		a.recordFail(ctx, username)
-		a.sec.LoginFail(ctx, username, remoteIP, "bad_totp")
-		return "", nil, ErrInvalidCredentials
+	// Second factor: skip only for a device already trusted by THIS admin.
+	if !a.trusted.Check(ctx, trustToken, admin.ID) {
+		secret, derr := DecryptSecret(a.secret, admin.TOTPSecretEnc)
+		if derr != nil {
+			a.recordFail(ctx, username)
+			a.sec.LoginFail(ctx, username, remoteIP, "totp_decrypt")
+			return LoginResult{}, ErrInvalidCredentials
+		}
+		if !totp.Validate(secret, code, a.now(), 1) {
+			a.recordFail(ctx, username)
+			a.sec.LoginFail(ctx, username, remoteIP, "bad_totp")
+			return LoginResult{}, ErrInvalidCredentials
+		}
 	}
 
 	// Success: clear counter, stamp login, create session.
 	a.clearFail(ctx, username)
 	if uerr := a.store.UpdateLastLogin(ctx, admin.ID, a.now()); uerr != nil {
-		return "", nil, fmt.Errorf("admin.Login update: %w", uerr)
+		return LoginResult{}, fmt.Errorf("admin.Login update: %w", uerr)
+	}
+
+	persistent := remember && a.trusted.Enabled()
+	var (
+		sid  string
+		sess *Session
+		serr error
+	)
+	if persistent {
+		sid, sess, serr = a.sessions.CreateWithTTL(ctx, admin.ID, admin.Username, a.trustTTL)
+	} else {
+		sid, sess, serr = a.sessions.Create(ctx, admin.ID, admin.Username)
 	}
-	sid, sess, serr := a.sessions.Create(ctx, admin.ID, admin.Username)
 	if serr != nil {
-		return "", nil, serr
+		return LoginResult{}, serr
+	}
+
+	res := LoginResult{SID: sid, Session: sess, Persistent: persistent}
+	if remember {
+		if tok, terr := a.trusted.Issue(ctx, admin.ID); terr == nil {
+			res.NewTrustToken = tok
+		}
 	}
 	a.sec.LoginOK(ctx, username, remoteIP)
-	return sid, sess, nil
+	return res, nil
 }
 
 func (a *Authenticator) isLocked(ctx context.Context, username string) (bool, error) {

server/internal/admin/config.go

@@ -44,6 +44,12 @@ type Config struct {
 	// CookieSecure controls the Secure attribute on the session cookie.
 	// Defaults to true; only disabled explicitly for local/dev over plain HTTP.
 	CookieSecure bool
+
+	// TrustedDeviceTTL is how long a "记住此设备" trust lasts. Within this window
+	// the device (a) skips the TOTP second factor on re-login and (b) keeps a
+	// persistent session of the same length. Password is ALWAYS still required.
+	// Zero disables the feature (checkbox has no effect).
+	TrustedDeviceTTL time.Duration
 }
 
 // defaultInternalCIDRs are the loopback and private/ULA ranges allowed by
@@ -66,6 +72,7 @@ var defaultInternalCIDRs = []string{
 //	ADMIN_LOGIN_FAIL_MAX  int                     (default 5)
 //	ADMIN_LOGIN_LOCK      Go duration             (default 15m)
 //	ADMIN_COOKIE_INSECURE "1" disables Secure flag (dev only)
+//	ADMIN_TRUSTED_DEVICE_TTL Go duration          (default 720h = 30d; 0 disables)
 func FromEnv() (*Config, error) {
 	c := &Config{
 		Listen:            getEnvDefault("ADMIN_LISTEN", "127.0.0.1:9443"),
@@ -73,6 +80,14 @@ func FromEnv() (*Config, error) {
 		LoginFailMax:      5,
 		LoginLockDuration: 15 * time.Minute,
 		CookieSecure:      os.Getenv("ADMIN_COOKIE_INSECURE") != "1",
+		TrustedDeviceTTL:  30 * 24 * time.Hour,
+	}
+	if v := os.Getenv("ADMIN_TRUSTED_DEVICE_TTL"); v != "" {
+		d, err := time.ParseDuration(v)
+		if err != nil {
+			return nil, fmt.Errorf("config: ADMIN_TRUSTED_DEVICE_TTL %q invalid: %w", v, err)
+		}
+		c.TrustedDeviceTTL = d
 	}
 
 	if err := validateListen(c.Listen); err != nil {

server/internal/admin/handlers.go

@@ -61,9 +61,15 @@ func (h *Handlers) LoginSubmit(w http.ResponseWriter, r *http.Request) {
 	username := strings.TrimSpace(r.PostFormValue("username"))
 	password := r.PostFormValue("password")
 	code := strings.TrimSpace(r.PostFormValue("totp"))
-	ip := hostOnly(r.RemoteAddr)
+	remember := r.PostFormValue("remember") != ""
+	ip := realIP(r) // 经本机 caddy 反代时取 XFF 末跳,否则 TCP 对端(见 mw_ipallow.go)
 
-	sid, _, err := h.auth.Login(r.Context(), username, password, code, ip)
+	var trustToken string
+	if c, cerr := r.Cookie(TrustedDeviceCookieName); cerr == nil {
+		trustToken = c.Value
+	}
+
+	res, err := h.auth.LoginDevice(r.Context(), username, password, code, ip, trustToken, remember)
 	if err != nil {
 		flash := "用户名、密码或动态验证码有误"
 		if err == ErrLockedOut {
@@ -73,7 +79,14 @@ func (h *Handlers) LoginSubmit(w http.ResponseWriter, r *http.Request) {
 		h.render.render(w, "login", pageData{Flash: flash})
 		return
 	}
-	h.setSessionCookie(w, sid)
+	if res.Persistent {
+		h.setSessionCookieTTL(w, res.SID, h.cfg.TrustedDeviceTTL)
+	} else {
+		h.setSessionCookie(w, res.SID)
+	}
+	if res.NewTrustToken != "" {
+		h.setTrustedCookie(w, res.NewTrustToken)
+	}
 	http.Redirect(w, r, "/", http.StatusFound)
 }
 
@@ -394,6 +407,14 @@ func (h *Handlers) writeAudit(ctx context.Context, actor, action, target, metaJS
 }
 
 func (h *Handlers) setSessionCookie(w http.ResponseWriter, sid string) {
+	h.setSessionCookieTTL(w, sid, h.cfg.SessionTTL)
+}
+
+// setSessionCookieTTL sets the session cookie with an explicit Max-Age. For a
+// persistent ("记住此设备") session ttl is the long trust-TTL; otherwise the
+// short idle default. Max-Age <= 0 would make it a session cookie, so ttl must
+// be positive here.
+func (h *Handlers) setSessionCookieTTL(w http.ResponseWriter, sid string, ttl time.Duration) {
 	http.SetCookie(w, &http.Cookie{
 		Name:     SessionCookieName,
 		Value:    sid,
@@ -401,7 +422,21 @@ func (h *Handlers) setSessionCookie(w http.ResponseWriter, sid string) {
 		HttpOnly: true,
 		Secure:   h.cfg.CookieSecure,
 		SameSite: http.SameSiteStrictMode,
-		MaxAge:   int(h.cfg.SessionTTL.Seconds()),
+		MaxAge:   int(ttl.Seconds()),
+	})
+}
+
+// setTrustedCookie stores the device-trust token (HttpOnly, Secure, Strict) so
+// this device can skip TOTP on future logins for the trust TTL.
+func (h *Handlers) setTrustedCookie(w http.ResponseWriter, token string) {
+	http.SetCookie(w, &http.Cookie{
+		Name:     TrustedDeviceCookieName,
+		Value:    token,
+		Path:     "/",
+		HttpOnly: true,
+		Secure:   h.cfg.CookieSecure,
+		SameSite: http.SameSiteStrictMode,
+		MaxAge:   int(h.cfg.TrustedDeviceTTL.Seconds()),
 	})
 }
 

server/internal/admin/login_device_handler_test.go

@@ -0,0 +1,114 @@
+package admin
+
+import (
+	"crypto/rand"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/alicebob/miniredis/v2"
+	"github.com/redis/go-redis/v9"
+	"github.com/wangjia/pangolin/server/internal/totp"
+)
+
+// newTrustEnv wires a full admin router with device-trust ENABLED and seeds
+// one admin, returning the router and that admin's TOTP secret.
+func newTrustEnv(t *testing.T) (http.Handler, string) {
+	t.Helper()
+	mr := miniredis.RunT(t)
+	rdb := redis.NewClient(&redis.Options{Addr: mr.Addr()})
+	t.Cleanup(func() { rdb.Close() })
+
+	key := make([]byte, 32)
+	if _, err := rand.Read(key); err != nil {
+		t.Fatal(err)
+	}
+	allow, _ := ParseCIDRs([]string{"127.0.0.0/8"})
+	cfg := &Config{
+		Listen: "127.0.0.1:9443", AllowCIDRs: allow, SecretKey: key,
+		SessionTTL: 30 * time.Minute, LoginFailMax: 3, LoginLockDuration: time.Minute,
+		CookieSecure: false, TrustedDeviceTTL: 30 * 24 * time.Hour,
+	}
+	store := newFakeStore()
+	secret := newTestAdmin(t, store, key, "alice", "s3cret-pass")
+
+	sessions := NewSessionStore(rdb, cfg.SessionTTL)
+	sec := NewSecurityLog(store, nil)
+	auth := NewAuthenticator(store, sessions, rdb, cfg, sec)
+	svc := Services{Codes: &fakeCodes{}, Lifecycle: &recordingLifecycle{ready: true}, Provision: &recordingProvision{ready: true}}
+	h, err := NewHandlers(cfg, store, sessions, auth, svc, sec, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return NewRouter(h, sessions, cfg, sec), secret
+}
+
+func cookieByName(resp *http.Response, name string) *http.Cookie {
+	for _, c := range resp.Cookies() {
+		if c.Name == name {
+			return c
+		}
+	}
+	return nil
+}
+
+func postLogin(t *testing.T, router http.Handler, form url.Values, cookies ...*http.Cookie) *http.Response {
+	t.Helper()
+	req := httptest.NewRequest("POST", "/login", strings.NewReader(form.Encode()))
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.RemoteAddr = "127.0.0.1:5000"
+	for _, c := range cookies {
+		req.AddCookie(c)
+	}
+	rr := httptest.NewRecorder()
+	router.ServeHTTP(rr, req)
+	return rr.Result()
+}
+
+// 端到端:勾选记住 → 登录成功 → 同时下发会话 cookie 与信任 cookie;
+// 随后仅凭信任 cookie + 空 TOTP 再次登录成功(免二次验证)。
+func TestLoginHandler_RememberThenSkipTOTP(t *testing.T) {
+	router, secret := newTrustEnv(t)
+	code, _ := totp.Code(secret, time.Now().UTC())
+
+	resp := postLogin(t, router, url.Values{
+		"username": {"alice"}, "password": {"s3cret-pass"},
+		"totp": {code}, "remember": {"1"},
+	})
+	if resp.StatusCode != http.StatusFound {
+		t.Fatalf("remember login: status = %d, want 302", resp.StatusCode)
+	}
+	trust := cookieByName(resp, TrustedDeviceCookieName)
+	if trust == nil || trust.Value == "" {
+		t.Fatal("remember login should set a non-empty trusted cookie")
+	}
+	if trust.MaxAge <= 0 {
+		t.Errorf("trusted cookie MaxAge = %d, want > 0 (persistent)", trust.MaxAge)
+	}
+	sessCookie := cookieByName(resp, SessionCookieName)
+	if sessCookie == nil || sessCookie.MaxAge <= int((30 * time.Minute).Seconds()) {
+		t.Error("remember login should set a long-lived (persistent) session cookie")
+	}
+
+	// 第二次:只带信任 cookie,TOTP 留空 → 成功
+	resp2 := postLogin(t, router, url.Values{
+		"username": {"alice"}, "password": {"s3cret-pass"}, "totp": {""},
+	}, &http.Cookie{Name: TrustedDeviceCookieName, Value: trust.Value})
+	if resp2.StatusCode != http.StatusFound {
+		t.Fatalf("trusted re-login: status = %d, want 302 (TOTP skipped)", resp2.StatusCode)
+	}
+}
+
+// 无信任 cookie + 空 TOTP → 401(二次验证仍强制)。
+func TestLoginHandler_NoTrustEmptyTOTPRejected(t *testing.T) {
+	router, _ := newTrustEnv(t)
+	resp := postLogin(t, router, url.Values{
+		"username": {"alice"}, "password": {"s3cret-pass"}, "totp": {""},
+	})
+	if resp.StatusCode != http.StatusUnauthorized {
+		t.Fatalf("empty TOTP without trust: status = %d, want 401", resp.StatusCode)
+	}
+}

server/internal/admin/login_device_test.go

@@ -0,0 +1,114 @@
+package admin
+
+import (
+	"context"
+	"crypto/rand"
+	"testing"
+	"time"
+
+	"github.com/wangjia/pangolin/server/internal/totp"
+)
+
+// newTrustAuth builds an Authenticator with device-trust ENABLED (30d).
+func newTrustAuth(t *testing.T) (*Authenticator, *fakeStore, []byte) {
+	t.Helper()
+	rdb, _ := newTestRedis(t)
+	key := make([]byte, 32)
+	if _, err := rand.Read(key); err != nil {
+		t.Fatal(err)
+	}
+	store := newFakeStore()
+	cfg := &Config{
+		SecretKey: key, LoginFailMax: 3, LoginLockDuration: time.Minute,
+		SessionTTL: 30 * time.Minute, TrustedDeviceTTL: 30 * 24 * time.Hour,
+	}
+	sessions := NewSessionStore(rdb, cfg.SessionTTL)
+	sec := NewSecurityLog(store, nil)
+	return NewAuthenticator(store, sessions, rdb, cfg, sec), store, key
+}
+
+// 勾选「记住此设备」成功登录 → 返回可用于下次跳过 TOTP 的信任令牌。
+func TestLoginDevice_RememberIssuesTrust(t *testing.T) {
+	auth, store, key := newTrustAuth(t)
+	secret := newTestAdmin(t, store, key, "alice", "s3cret-pass")
+	code, _ := totp.Code(secret, time.Now().UTC())
+	ctx := context.Background()
+
+	res, err := auth.LoginDevice(ctx, "alice", "s3cret-pass", code, "127.0.0.1", "", true)
+	if err != nil {
+		t.Fatalf("login: %v", err)
+	}
+	if res.NewTrustToken == "" {
+		t.Fatal("remember=true should issue a trust token")
+	}
+	if !res.Persistent {
+		t.Error("remember=true should mark session persistent")
+	}
+	// 下次:带该令牌 + 空 TOTP 也能登录(跳过二次验证)
+	res2, err := auth.LoginDevice(ctx, "alice", "s3cret-pass", "", "127.0.0.1", res.NewTrustToken, false)
+	if err != nil {
+		t.Fatalf("trusted re-login should skip TOTP: %v", err)
+	}
+	if res2.SID == "" {
+		t.Fatal("no session on trusted re-login")
+	}
+}
+
+// 不勾选:不签发令牌,且 TOTP 仍必填。
+func TestLoginDevice_NoRememberRequiresTOTP(t *testing.T) {
+	auth, store, key := newTrustAuth(t)
+	secret := newTestAdmin(t, store, key, "alice", "s3cret-pass")
+	code, _ := totp.Code(secret, time.Now().UTC())
+	ctx := context.Background()
+
+	res, err := auth.LoginDevice(ctx, "alice", "s3cret-pass", code, "127.0.0.1", "", false)
+	if err != nil {
+		t.Fatalf("login: %v", err)
+	}
+	if res.NewTrustToken != "" {
+		t.Error("remember=false must not issue a trust token")
+	}
+	// 无令牌 + 空 TOTP → 拒
+	if _, err := auth.LoginDevice(ctx, "alice", "s3cret-pass", "", "127.0.0.1", "", false); err != ErrInvalidCredentials {
+		t.Errorf("untrusted device with empty TOTP should fail, got %v", err)
+	}
+}
+
+// 铁律:即便持有效信任令牌,密码错误一律拒(只跳过 TOTP,不跳过密码)。
+func TestLoginDevice_TrustNeverSkipsPassword(t *testing.T) {
+	auth, store, key := newTrustAuth(t)
+	secret := newTestAdmin(t, store, key, "alice", "s3cret-pass")
+	code, _ := totp.Code(secret, time.Now().UTC())
+	ctx := context.Background()
+
+	res, _ := auth.LoginDevice(ctx, "alice", "s3cret-pass", code, "127.0.0.1", "", true)
+	if res.NewTrustToken == "" {
+		t.Fatal("precondition: expected trust token")
+	}
+	if _, err := auth.LoginDevice(ctx, "alice", "WRONG", "", "127.0.0.1", res.NewTrustToken, false); err != ErrInvalidCredentials {
+		t.Errorf("trusted device must still require correct password, got %v", err)
+	}
+}
+
+// 信任令牌绑定 admin:换个用户名不认(令牌属 alice,拿去登 bob 无效)。
+func TestLoginDevice_TrustBoundToAdmin(t *testing.T) {
+	auth, store, key := newTrustAuth(t)
+	sa := newTestAdmin(t, store, key, "alice", "alice-pass")
+	_ = sa
+	// bob:另一个 admin,不同 ID
+	hash, _ := HashPassword("bob-pass")
+	bsecret, _ := totp.GenerateSecret()
+	benc, _ := EncryptSecret(key, bsecret)
+	store.admins["bob"] = &Admin{ID: 2, Username: "bob", PwHash: hash, TOTPSecretEnc: benc, Status: "active"}
+	ctx := context.Background()
+
+	acode, _ := totp.Code(sa, time.Now().UTC())
+	ares, _ := auth.LoginDevice(ctx, "alice", "alice-pass", acode, "127.0.0.1", "", true)
+	if ares.NewTrustToken == "" {
+		t.Fatal("precondition: alice trust token")
+	}
+	// 用 alice 的令牌 + 空 TOTP 登 bob → 应要求 TOTP(令牌对 bob 无效)
+	if _, err := auth.LoginDevice(ctx, "bob", "bob-pass", "", "127.0.0.1", ares.NewTrustToken, false); err != ErrInvalidCredentials {
+		t.Errorf("alice's trust token must not skip TOTP for bob, got %v", err)
+	}
+}

server/internal/admin/mw_ipallow.go

@@ -3,6 +3,7 @@ package admin
 import (
 	"net"
 	"net/http"
+	"strings"
 )
 
 // IPAllow is middleware that rejects any request whose source IP is not within
@@ -58,3 +59,28 @@ func hostOnly(remoteAddr string) string {
 	}
 	return host
 }
+
+// realIP returns the client IP for **audit logging** (admin_login_ok 等)。
+//
+// 与上面 IPAllow 的取址原则刻意不同:白名单闸继续只看 TCP 对端(不可伪造);
+// 而审计日志要的是"人从哪来"——经本机反代(caddy mTLS 网关在同机回环上反代
+// 127.0.0.1:9444)时 RemoteAddr 恒为 loopback,没有溯源价值。仅当 TCP 对端是
+// loopback(即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,不可信)。
+func realIP(r *http.Request) string {
+	peer := hostOnly(r.RemoteAddr)
+	ip := net.ParseIP(peer)
+	if ip == nil || !ip.IsLoopback() {
+		return peer
+	}
+	xff := r.Header.Get("X-Forwarded-For")
+	if xff == "" {
+		return peer
+	}
+	parts := strings.Split(xff, ",")
+	last := strings.TrimSpace(parts[len(parts)-1])
+	if net.ParseIP(last) == nil {
+		return peer
+	}
+	return last
+}

server/internal/admin/realip_test.go

@@ -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)
+			}
+		})
+	}
+}

server/internal/admin/session.go

@@ -25,6 +25,9 @@ type Session struct {
 	Username  string    `json:"username"`
 	CSRFToken string    `json:"csrf"`
 	CreatedAt time.Time `json:"created_at"`
+	// TTLSeconds, when > 0, overrides the store's default sliding idle TTL for
+	// this session (used by "记住此设备" persistent sessions). 0 = use default.
+	TTLSeconds int64 `json:"ttl_seconds,omitempty"`
 }
 
 // SessionStore persists admin sessions in Redis with a sliding idle TTL.
@@ -41,9 +44,15 @@ func NewSessionStore(rdb *redis.Client, ttl time.Duration) *SessionStore {
 	return &SessionStore{rdb: rdb, ttl: ttl}
 }
 
-// Create starts a new session for the given admin and returns the opaque
-// session id (to be set as the cookie value).
+// Create starts a new session with the store's default sliding idle TTL.
 func (s *SessionStore) Create(ctx context.Context, adminID int64, username string) (string, *Session, error) {
+	return s.CreateWithTTL(ctx, adminID, username, 0)
+}
+
+// CreateWithTTL starts a new session. When ttl > 0 the session uses that TTL
+// (both the initial expiry and the per-request slide) instead of the store
+// default — this is how "记住此设备" keeps a device logged in for e.g. 30 days.
+func (s *SessionStore) CreateWithTTL(ctx context.Context, adminID int64, username string, ttl time.Duration) (string, *Session, error) {
 	sid, err := randToken(32)
 	if err != nil {
 		return "", nil, err
@@ -58,12 +67,24 @@ func (s *SessionStore) Create(ctx context.Context, adminID int64, username strin
 		CSRFToken: csrf,
 		CreatedAt: time.Now().UTC(),
 	}
+	if ttl > 0 {
+		sess.TTLSeconds = int64(ttl / time.Second)
+	}
 	if err := s.save(ctx, sid, sess); err != nil {
 		return "", nil, err
 	}
 	return sid, sess, nil
 }
 
+// slideTTL is the TTL to (re)apply to a session: its own override if set,
+// otherwise the store default.
+func (s *SessionStore) slideTTL(sess *Session) time.Duration {
+	if sess != nil && sess.TTLSeconds > 0 {
+		return time.Duration(sess.TTLSeconds) * time.Second
+	}
+	return s.ttl
+}
+
 // Get loads a session and slides its TTL forward. Returns (nil, nil) when the
 // session is absent or expired.
 func (s *SessionStore) Get(ctx context.Context, sid string) (*Session, error) {
@@ -81,8 +102,8 @@ func (s *SessionStore) Get(ctx context.Context, sid string) (*Session, error) {
 	if err := json.Unmarshal(val, &sess); err != nil {
 		return nil, fmt.Errorf("admin.SessionStore.Get unmarshal: %w", err)
 	}
-	// Slide the idle timeout.
-	if err := s.rdb.Expire(ctx, sessionKeyPrefix+sid, s.ttl).Err(); err != nil {
+	// Slide the idle timeout (persistent sessions slide by their own TTL).
+	if err := s.rdb.Expire(ctx, sessionKeyPrefix+sid, s.slideTTL(&sess)).Err(); err != nil {
 		return nil, fmt.Errorf("admin.SessionStore.Get expire: %w", err)
 	}
 	return &sess, nil
@@ -101,7 +122,7 @@ func (s *SessionStore) save(ctx context.Context, sid string, sess *Session) erro
 	if err != nil {
 		return fmt.Errorf("admin.SessionStore.save: %w", err)
 	}
-	if err := s.rdb.Set(ctx, sessionKeyPrefix+sid, b, s.ttl).Err(); err != nil {
+	if err := s.rdb.Set(ctx, sessionKeyPrefix+sid, b, s.slideTTL(sess)).Err(); err != nil {
 		return fmt.Errorf("admin.SessionStore.save set: %w", err)
 	}
 	return nil

server/internal/admin/templates/login.html

@@ -12,9 +12,10 @@
   {{if .Flash}}<div class="error">{{.Flash}}</div>{{end}}
   <label>用户名<input type="text" name="username" autocomplete="username" required autofocus></label>
   <label>密码<input type="password" name="password" autocomplete="current-password" required></label>
-  <label>动态验证码 (TOTP)<input type="text" name="totp" inputmode="numeric" autocomplete="one-time-code" pattern="[0-9]*" maxlength="6" required></label>
+  <label>动态验证码 (TOTP)<input type="text" name="totp" inputmode="numeric" autocomplete="one-time-code" pattern="[0-9]*" maxlength="6"></label>
+  <label class="checkbox"><input type="checkbox" name="remember" value="1"> 记住此设备（30 天内免动态码、保持登录）</label>
   <button type="submit">登录</button>
-  <p class="hint">仅限内网 / SSH 隧道访问。</p>
+  <p class="hint">仅限白名单设备（客户端证书）访问。已记住的设备可留空动态码。</p>
 </form>
 </body>
 </html>{{end}}

server/internal/admin/trusted.go

@@ -0,0 +1,74 @@
+package admin
+
+import (
+	"context"
+	"strconv"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+)
+
+// TrustedDeviceCookieName is the cookie holding a device-trust token.
+const TrustedDeviceCookieName = "admin_trusted"
+
+// trustedKeyPrefix namespaces device-trust tokens in Redis.
+const trustedKeyPrefix = "admin:trusted:"
+
+// TrustedStore records "记住此设备" device-trust tokens in Redis.
+//
+// A trusted token lets a device SKIP THE TOTP SECOND FACTOR on re-login
+// (password is still always required). Each token is opaque (32 bytes of
+// entropy), bound to one admin id, and expires after ttl — so a flushed
+// Redis, an expired token, or a mismatched admin all fail closed to
+// "TOTP required".
+type TrustedStore struct {
+	rdb *redis.Client
+	ttl time.Duration
+}
+
+// NewTrustedStore wires a TrustedStore. A ttl <= 0 disables the feature:
+// Issue returns an empty token and Check always returns false.
+func NewTrustedStore(rdb *redis.Client, ttl time.Duration) *TrustedStore {
+	return &TrustedStore{rdb: rdb, ttl: ttl}
+}
+
+// Enabled reports whether device-trust is active.
+func (s *TrustedStore) Enabled() bool { return s != nil && s.rdb != nil && s.ttl > 0 }
+
+// Issue mints a new trust token bound to adminID and stores it with the TTL.
+// Returns "" (no error) when the feature is disabled.
+func (s *TrustedStore) Issue(ctx context.Context, adminID int64) (string, error) {
+	if !s.Enabled() {
+		return "", nil
+	}
+	tok, err := randToken(32)
+	if err != nil {
+		return "", err
+	}
+	if err := s.rdb.Set(ctx, trustedKeyPrefix+tok, strconv.FormatInt(adminID, 10), s.ttl).Err(); err != nil {
+		return "", err
+	}
+	return tok, nil
+}
+
+// Check reports whether tok is a live trust token bound to adminID.
+// Any miss (disabled, empty, unknown, expired, wrong admin) returns false.
+func (s *TrustedStore) Check(ctx context.Context, tok string, adminID int64) bool {
+	if !s.Enabled() || tok == "" {
+		return false
+	}
+	v, err := s.rdb.Get(ctx, trustedKeyPrefix+tok).Result()
+	if err != nil {
+		return false
+	}
+	return v == strconv.FormatInt(adminID, 10)
+}
+
+// Revoke deletes a trust token (e.g. on explicit logout-all). A no-op when
+// disabled or empty.
+func (s *TrustedStore) Revoke(ctx context.Context, tok string) error {
+	if !s.Enabled() || tok == "" {
+		return nil
+	}
+	return s.rdb.Del(ctx, trustedKeyPrefix+tok).Err()
+}

server/internal/admin/trusted_test.go

@@ -0,0 +1,108 @@
+package admin
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/alicebob/miniredis/v2"
+	"github.com/redis/go-redis/v9"
+)
+
+func newTestTrustedStore(t *testing.T) (*TrustedStore, *miniredis.Miniredis) {
+	t.Helper()
+	mr, err := miniredis.Run()
+	if err != nil {
+		t.Fatalf("miniredis: %v", err)
+	}
+	t.Cleanup(mr.Close)
+	rdb := redis.NewClient(&redis.Options{Addr: mr.Addr()})
+	return NewTrustedStore(rdb, 30*24*time.Hour), mr
+}
+
+func TestTrustedStore_IssueThenCheck(t *testing.T) {
+	ts, _ := newTestTrustedStore(t)
+	ctx := context.Background()
+
+	tok, err := ts.Issue(ctx, 7)
+	if err != nil {
+		t.Fatalf("Issue: %v", err)
+	}
+	if tok == "" {
+		t.Fatal("Issue returned empty token")
+	}
+	// 正确 admin 命中
+	if !ts.Check(ctx, tok, 7) {
+		t.Error("Check should accept the token for the issuing admin")
+	}
+	// 令牌绑定 admin:换个 admin id 不认
+	if ts.Check(ctx, tok, 8) {
+		t.Error("Check must reject a token bound to a different admin")
+	}
+	// 未知令牌不认
+	if ts.Check(ctx, "bogus-token", 7) {
+		t.Error("Check must reject an unknown token")
+	}
+	// 空令牌不认
+	if ts.Check(ctx, "", 7) {
+		t.Error("Check must reject an empty token")
+	}
+}
+
+func TestTrustedStore_Revoke(t *testing.T) {
+	ts, _ := newTestTrustedStore(t)
+	ctx := context.Background()
+	tok, _ := ts.Issue(ctx, 7)
+	if !ts.Check(ctx, tok, 7) {
+		t.Fatal("precondition: token should be valid")
+	}
+	if err := ts.Revoke(ctx, tok); err != nil {
+		t.Fatalf("Revoke: %v", err)
+	}
+	if ts.Check(ctx, tok, 7) {
+		t.Error("Check must reject a revoked token")
+	}
+}
+
+func TestTrustedStore_Expires(t *testing.T) {
+	mr, err := miniredis.Run()
+	if err != nil {
+		t.Fatalf("miniredis: %v", err)
+	}
+	defer mr.Close()
+	rdb := redis.NewClient(&redis.Options{Addr: mr.Addr()})
+	ts := NewTrustedStore(rdb, time.Hour)
+	ctx := context.Background()
+
+	tok, _ := ts.Issue(ctx, 7)
+	if !ts.Check(ctx, tok, 7) {
+		t.Fatal("precondition: token valid before expiry")
+	}
+	mr.FastForward(2 * time.Hour) // 超过 TTL
+	if ts.Check(ctx, tok, 7) {
+		t.Error("Check must reject an expired token (fail-closed)")
+	}
+}
+
+// TTL<=0 视为功能关闭:Issue 返回空、Check 恒 false。
+func TestTrustedStore_Disabled(t *testing.T) {
+	mr, err := miniredis.Run()
+	if err != nil {
+		t.Fatalf("miniredis: %v", err)
+	}
+	defer mr.Close()
+	rdb := redis.NewClient(&redis.Options{Addr: mr.Addr()})
+	ts := NewTrustedStore(rdb, 0)
+	ctx := context.Background()
+
+	tok, err := ts.Issue(ctx, 7)
+	if err != nil {
+		t.Fatalf("Issue: %v", err)
+	}
+	if tok != "" {
+		t.Error("disabled store should issue empty token")
+	}
+	if ts.Check(ctx, "anything", 7) {
+		t.Error("disabled store should never trust")
+	}
+}