Login page for AUTH_MODE=local instead of the Basic Auth popup

The local mode now shows a login page in the colors of the UI (light/dark theme, FR/EN)
with a signed session cookie and the log out button, like the OIDC mode. LOGIN_LOGO shows
a PNG mounted in the container on that page. SESSION_TTL applies to both modes
(OIDC_SESSION_TTL still works). HTTP Basic credentials are still accepted for scripts.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.env.example

@@ -4,11 +4,16 @@ HTTP_PORT=8080
 TZ=Europe/Paris
 # How long logs are kept (e.g. 7d, 30d, 12w, 1y)
 RETENTION=30d
-# Web UI authentication: local (HTTP Basic below, or none) or oidc (OpenID Connect provider)
+# Web UI authentication: local (login page with the account below, or none) or oidc (OpenID Connect provider)
 AUTH_MODE=local
 # local mode: user and password (empty = no authentication)
 AUTH_USER=
 AUTH_PASS=
+# local mode: PNG logo shown on the login page, path inside the container (empty = no logo).
+# Mount the file in docker-compose.yml, e.g. ./logo.png:/config/logo.png:ro, then LOGIN_LOGO=/config/logo.png
+LOGIN_LOGO=
+# Session lifetime, both modes (e.g. 8h, 24h)
+SESSION_TTL=12h
 # oidc mode: issuer URL exactly as the provider announces it
 # (Keycloak: https://sso.example.org/realms/<realm>, Authentik: https://auth.example.org/application/o/<slug>/)
 OIDC_ISSUER=
@@ -16,9 +21,8 @@ OIDC_CLIENT_ID=
 OIDC_CLIENT_SECRET=
 # Callback URL of logstream, to register in the provider (path free, /auth/callback recommended)
 OIDC_REDIRECT_URL=https://logs.example.org/auth/callback
-# Requested scopes (openid is always added) and session lifetime (e.g. 8h, 24h)
+# Requested scopes (openid is always added)
 OIDC_SCOPES=openid profile email
-OIDC_SESSION_TTL=12h
 # Reverse DNS: show host names instead of IP addresses (on/off)
 RDNS=on
 # DNS server used for reverse lookups (e.g. your router: 192.168.1.1). Empty = system resolver

README.fr.md

@@ -250,11 +250,31 @@ couleur, est mémorisé par navigateur.
 
 `AUTH_MODE` choisit comment l'interface et l'API sont protégées (`/healthz` reste toujours ouvert) :
 
-- **`local`** (par défaut) : authentification HTTP Basic avec `AUTH_USER` / `AUTH_PASS` ; laissez-les
+- **`local`** (par défaut) : une page de connexion avec le compte `AUTH_USER` / `AUTH_PASS` ; laissez-les
   vides pour n'avoir aucune authentification (par exemple derrière un reverse proxy qui contrôle déjà).
 - **`oidc`** : connexion par un fournisseur OpenID Connect (Keycloak, Authentik, Authelia, Zitadel…),
   flux « authorization code » avec PKCE.
 
+En mode `local`, la page de connexion suit le thème et la langue de l'interface. La session dure
+`SESSION_TTL` (12 h par défaut), survit aux redémarrages (sa clé de signature est dans
+`/data/session.key`) et se termine quand `AUTH_USER` ou `AUTH_PASS` change ; le bouton de
+déconnexion (en haut à droite) y met fin. Les échecs de connexion sont écrits dans les logs avec
+l'adresse du client (`auth: failed login for "bob" from 192.0.2.7`). Les scripts peuvent toujours
+appeler l'API avec des identifiants HTTP Basic (`curl -u utilisateur:motdepasse`).
+
+Pour afficher votre logo sur la page de connexion, montez un PNG dans le conteneur et indiquez
+son chemin dans `LOGIN_LOGO` :
+
+```yaml
+# docker-compose.yml, service logstream
+    volumes:
+      - ./logo.png:/config/logo.png:ro
+```
+```bash
+# .env
+LOGIN_LOGO=/config/logo.png
+```
+
 Pour utiliser OIDC :
 
 1. Dans le fournisseur, créez un client **confidentiel** (avec secret) pour logstream et déclarez
@@ -271,7 +291,7 @@ Pour utiliser OIDC :
    laquelle le fournisseur n'a pas pu être lu (issuer incorrect, injoignable…).
 
 Ouvrir l'interface renvoie vers la page de connexion du fournisseur, puis revient sur logstream.
-La session dure `OIDC_SESSION_TTL` (12 h par défaut) et survit aux redémarrages (sa clé de
+La session dure `SESSION_TTL` (12 h par défaut) et survit aux redémarrages (sa clé de
 signature est dans `/data/session.key`) ; à son expiration, la page repasse par la connexion. Le
 bouton de déconnexion (en haut à droite) termine la session logstream, puis ouvre la page de
 déconnexion du fournisseur s'il en a une.
@@ -302,13 +322,14 @@ résolutions.
 | `SYSLOG_PORT` | `514` | port syslog publié sur l'hôte |
 | `HTTP_PORT` | `8080` | port de l'interface web |
 | `RETENTION` | `30d` | durée de conservation des logs dans VictoriaLogs |
-| `AUTH_MODE` | `local` | `local` (HTTP Basic) ou `oidc`, voir [Authentification](#authentification) |
-| `AUTH_USER` / `AUTH_PASS` | vide | authentification HTTP Basic pour l'interface (mode `local`) |
+| `AUTH_MODE` | `local` | `local` (page de connexion) ou `oidc`, voir [Authentification](#authentification) |
+| `AUTH_USER` / `AUTH_PASS` | vide | compte de la page de connexion (mode `local`) ; vide = pas d'authentification |
+| `LOGIN_LOGO` | vide | PNG affiché sur la page de connexion, chemin dans le conteneur (mode `local`) |
+| `SESSION_TTL` | `12h` | durée de la session (les deux modes ; `OIDC_SESSION_TTL` fonctionne toujours) |
 | `OIDC_ISSUER` | vide | URL de l'issuer du fournisseur OpenID Connect (mode `oidc`) |
 | `OIDC_CLIENT_ID` / `OIDC_CLIENT_SECRET` | vide | client déclaré dans le fournisseur |
 | `OIDC_REDIRECT_URL` | vide | URL de retour de logstream, ex. `https://logs.example.org/auth/callback` |
 | `OIDC_SCOPES` | `openid profile email` | scopes demandés |
-| `OIDC_SESSION_TTL` | `12h` | durée de la session |
 | `RDNS` | `on` | résoudre les hôtes donnés par leur IP en noms DNS |
 | `DNS_SERVER` | vide | serveur DNS pour les résolutions inverses (`ip` ou `ip:port`) |
 | `ALLOW_PURGE` | `true` | autoriser « Supprimer tous les logs » dans les Paramètres |
@@ -366,7 +387,8 @@ Pour mettre à jour l'une d'elles :
 | Fichier | Contenu |
 |---|---|
 | `main.go` | configuration, démarrage |
-| `auth.go` | authentification : HTTP Basic ou OpenID Connect (découverte, PKCE, contrôle de l'ID token, cookie de session) |
+| `auth.go` | authentification : OpenID Connect (découverte, PKCE, contrôle de l'ID token) et cookie de session signé |
+| `auth_local.go` | mode `local` : page de connexion (`web/login.html`), cookie de session, `LOGIN_LOGO` |
 | `syslog.go` | écoute UDP/TCP et analyse RFC 3164 / 5424 |
 | `store.go` | insertions par lots dans VictoriaLogs et requêtes LogsQL |
 | `query.go` | traduit les filtres de l'interface en LogsQL ; filtre du direct |
@@ -379,7 +401,7 @@ Pour mettre à jour l'une d'elles :
 | `hostlogs.go`, `journal.go` | logs système de l'hôte : lecteur du journal systemd (sans `journalctl`) et suivi de `/var/log` |
 | `tags.go` | stockage des tags de couleur |
 | `api.go` | routes HTTP `/api/*` |
-| `web/` | interface (HTML, CSS, JavaScript simple, sans étape de build), embarquée dans le binaire ; les traductions sont dans `web/app.js` (`I18N`) |
+| `web/` | interface (HTML, CSS, JavaScript simple, sans étape de build), embarquée dans le binaire ; les traductions sont dans `web/app.js` (`I18N`), et dans `web/login.html` pour la page de connexion |
 
 ## Remarque
 

README.md

@@ -226,11 +226,29 @@ remembered per browser.
 
 `AUTH_MODE` picks how the UI and the API are protected (`/healthz` always stays open):
 
-- **`local`** (default): HTTP Basic authentication with `AUTH_USER` / `AUTH_PASS`; leave them
+- **`local`** (default): a login page with the account `AUTH_USER` / `AUTH_PASS`; leave them
   empty to have no authentication (for instance behind a reverse proxy that already checks).
 - **`oidc`**: login through an OpenID Connect provider (Keycloak, Authentik, Authelia, Zitadel…),
   authorization code flow with PKCE.
 
+In `local` mode the login page follows the theme and language of the UI. The session lasts
+`SESSION_TTL` (12 h by default), survives restarts (its signing key is in `/data/session.key`) and
+ends when `AUTH_USER` or `AUTH_PASS` changes; the log out button (top right) ends it. Failed logins
+are written in the logs with the client address (`auth: failed login for "bob" from 192.0.2.7`).
+Scripts can still call the API with HTTP Basic credentials (`curl -u user:pass`).
+
+To show your logo on the login page, mount a PNG in the container and point `LOGIN_LOGO` to it:
+
+```yaml
+# docker-compose.yml, logstream service
+    volumes:
+      - ./logo.png:/config/logo.png:ro
+```
+```bash
+# .env
+LOGIN_LOGO=/config/logo.png
+```
+
 To use OIDC:
 
 1. In the provider, create a **confidential** client (with a secret) for logstream and register
@@ -247,7 +265,7 @@ To use OIDC:
    provider could not be read (wrong issuer, unreachable…).
 
 Opening the UI sends you to the provider's login page, then back to logstream. The session
-lasts `OIDC_SESSION_TTL` (12 h by default) and survives restarts (its signing key is in
+lasts `SESSION_TTL` (12 h by default) and survives restarts (its signing key is in
 `/data/session.key`); when it ends, the page goes through the login again. The log out button
 (top right) ends the logstream session, then opens the provider's log out page if it has one.
 
@@ -274,13 +292,14 @@ are only known by your router or a local DNS (Pi-hole, AdGuard, Unbound…), set
 | `SYSLOG_PORT` | `514` | syslog port published on the host |
 | `HTTP_PORT` | `8080` | web UI port |
 | `RETENTION` | `30d` | how long VictoriaLogs keeps logs |
-| `AUTH_MODE` | `local` | `local` (HTTP Basic) or `oidc`, see [Authentication](#authentication) |
-| `AUTH_USER` / `AUTH_PASS` | empty | HTTP Basic authentication for the UI (`local` mode) |
+| `AUTH_MODE` | `local` | `local` (login page) or `oidc`, see [Authentication](#authentication) |
+| `AUTH_USER` / `AUTH_PASS` | empty | account of the login page (`local` mode); empty = no authentication |
+| `LOGIN_LOGO` | empty | PNG shown on the login page, path inside the container (`local` mode) |
+| `SESSION_TTL` | `12h` | session lifetime (both modes; `OIDC_SESSION_TTL` still works) |
 | `OIDC_ISSUER` | empty | issuer URL of the OpenID Connect provider (`oidc` mode) |
 | `OIDC_CLIENT_ID` / `OIDC_CLIENT_SECRET` | empty | client registered in the provider |
 | `OIDC_REDIRECT_URL` | empty | callback URL of logstream, e.g. `https://logs.example.org/auth/callback` |
 | `OIDC_SCOPES` | `openid profile email` | requested scopes |
-| `OIDC_SESSION_TTL` | `12h` | session lifetime |
 | `RDNS` | `on` | resolve IP hosts to DNS names |
 | `DNS_SERVER` | empty | DNS server for reverse lookups (`ip` or `ip:port`) |
 | `ALLOW_PURGE` | `true` | allow "Delete all logs" in Settings |
@@ -335,7 +354,8 @@ To update one of them:
 | File | Contents |
 |---|---|
 | `main.go` | configuration, startup |
-| `auth.go` | authentication: HTTP Basic or OpenID Connect (discovery, PKCE, ID token checks, session cookie) |
+| `auth.go` | authentication: OpenID Connect (discovery, PKCE, ID token checks) and the signed session cookie |
+| `auth_local.go` | `local` mode: login page (`web/login.html`), session cookie, `LOGIN_LOGO` |
 | `syslog.go` | UDP/TCP listeners and RFC 3164 / 5424 parsing |
 | `store.go` | batched inserts into VictoriaLogs and LogsQL queries |
 | `query.go` | turns UI filters into LogsQL; live-view filter |
@@ -348,7 +368,7 @@ To update one of them:
 | `hostlogs.go`, `journal.go` | host system logs: systemd journal reader (no `journalctl`) and `/var/log` follower |
 | `tags.go` | color tag storage |
 | `api.go` | `/api/*` HTTP routes |
-| `web/` | UI (HTML, CSS, plain JavaScript, no build step), embedded in the binary; translations live in `web/app.js` (`I18N`) |
+| `web/` | UI (HTML, CSS, plain JavaScript, no build step), embedded in the binary; translations live in `web/app.js` (`I18N`), and in `web/login.html` for the login page |
 
 ## Note
 

auth.go

@@ -27,8 +27,8 @@ import (
 	"time"
 )
 
-// Web UI authentication. AUTH_MODE=local (default) keeps the optional HTTP Basic
-// authentication (AUTH_USER / AUTH_PASS); AUTH_MODE=oidc delegates the login to an
+// Web UI authentication. AUTH_MODE=local (default) shows a login page when AUTH_USER /
+// AUTH_PASS are set (auth_local.go); AUTH_MODE=oidc delegates the login to an
 // OpenID Connect provider (Keycloak, Authentik, Authelia…) with the authorization code
 // flow and PKCE. Only the standard library is used.
 
@@ -49,13 +49,23 @@ type authConfig struct {
 	scopes       string
 	sessionTTL   time.Duration
 	dataDir      string
+	loginLogo    string // local mode: PNG shown on the login page
+
 }
 
 // newAuth returns the middleware that protects the UI and the API (except /healthz).
 func newAuth(c authConfig, next http.Handler) (http.Handler, error) {
+	if c.sessionTTL <= 0 {
+		c.sessionTTL = 12 * time.Hour
+	}
 	switch strings.ToLower(c.mode) {
 	case "", "local":
-		return basicAuth(c.user, c.pass, next), nil
+		if c.user == "" {
+			return next, nil
+		}
+		l := newLocal(c)
+		l.next = next
+		return l, nil
 	case "oidc":
 		o, err := newOIDC(c)
 		if err != nil {
@@ -68,28 +78,6 @@ func newAuth(c authConfig, next http.Handler) (http.Handler, error) {
 	return nil, fmt.Errorf("AUTH_MODE=%q: expected local or oidc", c.mode)
 }
 
-// basicAuth protects the UI when AUTH_USER is set (except /healthz).
-func basicAuth(user, pass string, next http.Handler) http.Handler {
-	if user == "" {
-		return next
-	}
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if r.URL.Path == "/healthz" {
-			next.ServeHTTP(w, r)
-			return
-		}
-		u, p, ok := r.BasicAuth()
-		if !ok ||
-			subtle.ConstantTimeCompare([]byte(u), []byte(user)) != 1 ||
-			subtle.ConstantTimeCompare([]byte(p), []byte(pass)) != 1 {
-			w.Header().Set("WWW-Authenticate", `Basic realm="logstream"`)
-			http.Error(w, "authentication required", http.StatusUnauthorized)
-			return
-		}
-		next.ServeHTTP(w, r)
-	})
-}
-
 type oidcMeta struct {
 	Issuer           string   `json:"issuer"`
 	AuthEndpoint     string   `json:"authorization_endpoint"`
@@ -136,9 +124,6 @@ func newOIDC(c authConfig) (*OIDC, error) {
 	if !strings.Contains(" "+c.scopes+" ", " openid ") {
 		c.scopes = "openid " + c.scopes
 	}
-	if c.sessionTTL <= 0 {
-		c.sessionTTL = 12 * time.Hour
-	}
 	return &OIDC{
 		cfg:      c,
 		callback: ru.Path,
@@ -166,7 +151,7 @@ func sessionKey(dir string) []byte {
 		log.Fatalf("session key: %v", err)
 	}
 	if err := os.WriteFile(path, k, 0o600); err != nil {
-		log.Printf("oidc: cannot save %s (%v): sessions end when logstream restarts", path, err)
+		log.Printf("auth: cannot save %s (%v): sessions end when logstream restarts", path, err)
 	}
 	return k
 }
@@ -176,6 +161,14 @@ type session struct {
 	Exp  int64  `json:"e"`
 }
 
+// writeAuthRequired answers API calls without a session; the UI turns it into a reload
+// (and so into a new login).
+func writeAuthRequired(w http.ResponseWriter) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusUnauthorized)
+	_, _ = w.Write([]byte(`{"error":"authentication required","code":"auth"}` + "\n"))
+}
+
 type loginState struct {
 	Nonce    string `json:"n"`
 	Verifier string `json:"v"`
@@ -196,7 +189,7 @@ func (o *OIDC) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	var s session
-	if c, err := r.Cookie(sessionCookie); err == nil && o.verifyCookie(c.Value, &s) && time.Now().Unix() < s.Exp {
+	if c, err := r.Cookie(sessionCookie); err == nil && verifyCookie(o.key, c.Value, &s) && time.Now().Unix() < s.Exp {
 		if r.URL.Path == "/auth/me" {
 			writeJSON(w, http.StatusOK, map[string]string{"mode": "oidc", "user": s.User})
 			return
@@ -210,9 +203,7 @@ func (o *OIDC) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		o.startLogin(w, r)
 		return
 	}
-	w.Header().Set("Content-Type", "application/json")
-	w.WriteHeader(http.StatusUnauthorized)
-	_, _ = w.Write([]byte(`{"error":"authentication required","code":"auth"}` + "\n"))
+	writeAuthRequired(w)
 }
 
 func (o *OIDC) startLogin(w http.ResponseWriter, r *http.Request) {
@@ -229,7 +220,7 @@ func (o *OIDC) startLogin(w http.ResponseWriter, r *http.Request) {
 	}
 	http.SetCookie(w, &http.Cookie{
 		Name:     loginCookie + state,
-		Value:    o.signCookie(loginState{Nonce: nonce, Verifier: verifier, Return: ret, Exp: time.Now().Add(loginTTL).Unix()}),
+		Value:    signCookie(o.key, loginState{Nonce: nonce, Verifier: verifier, Return: ret, Exp: time.Now().Add(loginTTL).Unix()}),
 		Path:     "/",
 		MaxAge:   int(loginTTL.Seconds()),
 		HttpOnly: true,
@@ -260,7 +251,7 @@ func (o *OIDC) handleCallback(w http.ResponseWriter, r *http.Request) {
 	state := q.Get("state")
 	var ls loginState
 	c, err := r.Cookie(loginCookie + state)
-	if state == "" || err != nil || !o.verifyCookie(c.Value, &ls) || time.Now().Unix() > ls.Exp {
+	if state == "" || err != nil || !verifyCookie(o.key, c.Value, &ls) || time.Now().Unix() > ls.Exp {
 		http.Error(w, "login expired or started in another browser: open logstream again", http.StatusBadRequest)
 		return
 	}
@@ -275,7 +266,7 @@ func (o *OIDC) handleCallback(w http.ResponseWriter, r *http.Request) {
 	log.Printf("oidc: %s logged in", user)
 	http.SetCookie(w, &http.Cookie{
 		Name:     sessionCookie,
-		Value:    o.signCookie(session{User: user, Exp: time.Now().Add(o.cfg.sessionTTL).Unix()}),
+		Value:    signCookie(o.key, session{User: user, Exp: time.Now().Add(o.cfg.sessionTTL).Unix()}),
 		Path:     "/",
 		MaxAge:   int(o.cfg.sessionTTL.Seconds()),
 		HttpOnly: true,
@@ -564,15 +555,15 @@ func (o *OIDC) getJSON(u string, v any) error {
 }
 
 // Cookies are base64url(JSON) + "." + base64url(HMAC-SHA256).
-func (o *OIDC) signCookie(v any) string {
+func signCookie(key []byte, v any) string {
 	b, _ := json.Marshal(v)
 	p := base64.RawURLEncoding.EncodeToString(b)
-	m := hmac.New(sha256.New, o.key)
+	m := hmac.New(sha256.New, key)
 	m.Write([]byte(p))
 	return p + "." + base64.RawURLEncoding.EncodeToString(m.Sum(nil))
 }
 
-func (o *OIDC) verifyCookie(s string, v any) bool {
+func verifyCookie(key []byte, s string, v any) bool {
 	p, sig, ok := strings.Cut(s, ".")
 	if !ok {
 		return false
@@ -581,7 +572,7 @@ func (o *OIDC) verifyCookie(s string, v any) bool {
 	if err != nil {
 		return false
 	}
-	m := hmac.New(sha256.New, o.key)
+	m := hmac.New(sha256.New, key)
 	m.Write([]byte(p))
 	if !hmac.Equal(got, m.Sum(nil)) {
 		return false

auth_local.go

@@ -0,0 +1,167 @@
+package main
+
+import (
+	"crypto/hmac"
+	"crypto/sha256"
+	"crypto/subtle"
+	"log"
+	"net"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+	"time"
+)
+
+// Local mode with AUTH_USER set: a login page (web/login.html) in the colors of the UI and a
+// session kept in a signed cookie, like the OIDC mode. HTTP Basic credentials are still
+// accepted so scripts calling the API keep working, but the browser popup is gone.
+
+const loginPage = "/login.html"
+
+var loginFailDelay = time.Second // slows down password guessing
+
+type Local struct {
+	user, pass string
+	ttl        time.Duration
+	logo       string // LOGIN_LOGO, served at /auth/logo
+	key        []byte
+	next       http.Handler
+}
+
+func newLocal(c authConfig) *Local {
+	// The key depends on the credentials: changing AUTH_USER or AUTH_PASS ends every session.
+	m := hmac.New(sha256.New, sessionKey(c.dataDir))
+	m.Write([]byte("local\x00" + c.user + "\x00" + c.pass))
+	if c.loginLogo != "" {
+		if _, err := os.Stat(c.loginLogo); err != nil {
+			log.Printf("auth: LOGIN_LOGO: %v", err)
+		}
+	}
+	log.Printf("local authentication enabled (user %s)", c.user)
+	return &Local{user: c.user, pass: c.pass, ttl: c.sessionTTL, logo: c.loginLogo, key: m.Sum(nil)}
+}
+
+func (l *Local) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	switch r.URL.Path {
+	case "/healthz", "/style.css":
+		l.next.ServeHTTP(w, r)
+		return
+	case "/auth/logo":
+		l.serveLogo(w, r)
+		return
+	case "/auth/login":
+		l.handleLogin(w, r)
+		return
+	case "/auth/logout":
+		http.SetCookie(w, &http.Cookie{Name: sessionCookie, Path: "/", MaxAge: -1, HttpOnly: true, Secure: isHTTPS(r)})
+		http.Redirect(w, r, loginPage, http.StatusFound)
+		return
+	}
+	user, ok := l.sessionUser(r)
+	if !ok {
+		if u, p, basic := r.BasicAuth(); basic && l.check(u, p) {
+			user, ok = u, true
+		}
+	}
+	switch {
+	case r.URL.Path == loginPage:
+		if ok {
+			http.Redirect(w, r, safeReturn(r.URL.Query().Get("r")), http.StatusFound)
+			return
+		}
+		w.Header().Set("Cache-Control", "no-store")
+		l.next.ServeHTTP(w, r)
+	case ok && r.URL.Path == "/auth/me":
+		writeJSON(w, http.StatusOK, map[string]string{"mode": "local", "user": user})
+	case ok:
+		l.next.ServeHTTP(w, r)
+	case r.Method == http.MethodGet && !strings.HasPrefix(r.URL.Path, "/api/") && r.URL.Path != "/auth/me":
+		target := loginPage
+		if ret := r.URL.RequestURI(); ret != "/" {
+			target += "?" + url.Values{"r": {ret}}.Encode()
+		}
+		http.Redirect(w, r, target, http.StatusFound)
+	default:
+		writeAuthRequired(w)
+	}
+}
+
+func (l *Local) handleLogin(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Redirect(w, r, loginPage, http.StatusFound)
+		return
+	}
+	user, pass := r.PostFormValue("user"), r.PostFormValue("pass")
+	ret := safeReturn(r.PostFormValue("r"))
+	if !l.check(user, pass) {
+		log.Printf("auth: failed login for %q from %s", user, clientIP(r))
+		time.Sleep(loginFailDelay)
+		q := url.Values{"e": {"1"}}
+		if ret != "/" {
+			q.Set("r", ret)
+		}
+		http.Redirect(w, r, loginPage+"?"+q.Encode(), http.StatusSeeOther)
+		return
+	}
+	log.Printf("auth: %s logged in from %s", user, clientIP(r))
+	http.SetCookie(w, &http.Cookie{
+		Name:     sessionCookie,
+		Value:    signCookie(l.key, session{User: user, Exp: time.Now().Add(l.ttl).Unix()}),
+		Path:     "/",
+		MaxAge:   int(l.ttl.Seconds()),
+		HttpOnly: true,
+		Secure:   isHTTPS(r),
+		SameSite: http.SameSiteLaxMode,
+	})
+	http.Redirect(w, r, ret, http.StatusSeeOther)
+}
+
+func (l *Local) sessionUser(r *http.Request) (string, bool) {
+	var s session
+	c, err := r.Cookie(sessionCookie)
+	if err != nil || !verifyCookie(l.key, c.Value, &s) || time.Now().Unix() >= s.Exp {
+		return "", false
+	}
+	return s.User, true
+}
+
+func (l *Local) check(user, pass string) bool {
+	u := subtle.ConstantTimeCompare([]byte(user), []byte(l.user))
+	p := subtle.ConstantTimeCompare([]byte(pass), []byte(l.pass))
+	return u&p == 1
+}
+
+// serveLogo sends LOGIN_LOGO; without it the login page hides the image.
+func (l *Local) serveLogo(w http.ResponseWriter, r *http.Request) {
+	if l.logo == "" {
+		http.NotFound(w, r)
+		return
+	}
+	w.Header().Set("Cache-Control", "no-cache")
+	http.ServeFile(w, r, l.logo)
+}
+
+// safeReturn keeps the page to open after login inside logstream.
+func safeReturn(ret string) string {
+	if !strings.HasPrefix(ret, "/") || strings.HasPrefix(ret, "//") || strings.HasPrefix(ret, "/\\") || ret == loginPage {
+		return "/"
+	}
+	return ret
+}
+
+// isHTTPS is true when the browser talks HTTPS, directly or through a reverse proxy.
+func isHTTPS(r *http.Request) bool {
+	return r.TLS != nil || strings.EqualFold(r.Header.Get("X-Forwarded-Proto"), "https")
+}
+
+func clientIP(r *http.Request) string {
+	if f := r.Header.Get("X-Forwarded-For"); f != "" {
+		return strings.TrimSpace(strings.Split(f, ",")[0])
+	}
+	host, _, err := net.SplitHostPort(r.RemoteAddr)
+	if err != nil {
+		return r.RemoteAddr
+	}
+	return host
+}

auth_local_test.go

@@ -0,0 +1,142 @@
+package main
+
+import (
+	"net/http"
+	"net/http/cookiejar"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+// newLocalApp puts the local login in front of a handler that echoes "app" and returns a
+// browser (client with cookies) that does not follow redirects.
+func newLocalApp(t *testing.T, c authConfig) (string, *http.Client) {
+	t.Helper()
+	loginFailDelay = 0
+	c.mode, c.dataDir = "local", t.TempDir()
+	h, err := newAuth(c, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { _, _ = w.Write([]byte("app " + r.URL.Path)) }))
+	if err != nil {
+		t.Fatal(err)
+	}
+	jar, _ := cookiejar.New(nil)
+	return "http://app.test", &http.Client{
+		Jar:           jar,
+		Transport:     hosts{"app.test": h},
+		CheckRedirect: func(*http.Request, []*http.Request) error { return http.ErrUseLastResponse },
+	}
+}
+
+func login(t *testing.T, c *http.Client, app, user, pass, ret string) *http.Response {
+	t.Helper()
+	res, err := c.PostForm(app+"/auth/login", url.Values{"user": {user}, "pass": {pass}, "r": {ret}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	res.Body.Close()
+	return res
+}
+
+func TestLocalLoginFlow(t *testing.T) {
+	app, c := newLocalApp(t, authConfig{user: "admin", pass: "pw"})
+
+	res, _ := c.Get(app + "/api/logs?q=x")
+	if res.StatusCode != http.StatusUnauthorized || res.Header.Get("WWW-Authenticate") != "" {
+		t.Fatalf("API without session: %d %q", res.StatusCode, res.Header.Get("WWW-Authenticate"))
+	}
+	res, _ = c.Get(app + "/?q=disk")
+	if loc := res.Header.Get("Location"); res.StatusCode != http.StatusFound || loc != "/login.html?r=%2F%3Fq%3Ddisk" {
+		t.Fatalf("page without session: %d %q", res.StatusCode, loc)
+	}
+	for _, p := range []string{"/login.html", "/style.css", "/healthz"} {
+		if code, body := get(t, c, app+p); code != http.StatusOK || body != "app "+p {
+			t.Errorf("%s without session: %d %q", p, code, body)
+		}
+	}
+
+	res = login(t, c, app, "admin", "wrong", "/?q=disk")
+	if loc := res.Header.Get("Location"); res.StatusCode != http.StatusSeeOther || !strings.Contains(loc, "e=1") {
+		t.Fatalf("wrong password: %d %q", res.StatusCode, loc)
+	}
+	if code, _ := get(t, c, app+"/api/logs"); code != http.StatusUnauthorized {
+		t.Fatal("session created by a wrong password")
+	}
+
+	res = login(t, c, app, "admin", "pw", "//evil.example/")
+	if loc := res.Header.Get("Location"); loc != "/" {
+		t.Fatalf("open redirect: %q", loc)
+	}
+	res = login(t, c, app, "admin", "pw", "/?q=disk")
+	if loc := res.Header.Get("Location"); res.StatusCode != http.StatusSeeOther || loc != "/?q=disk" {
+		t.Fatalf("login: %d %q", res.StatusCode, loc)
+	}
+	if code, body := get(t, c, app+"/api/logs"); code != http.StatusOK || body != "app /api/logs" {
+		t.Fatalf("API with session: %d %q", code, body)
+	}
+	if code, body := get(t, c, app+"/auth/me"); code != http.StatusOK || !strings.Contains(body, `"user":"admin"`) || !strings.Contains(body, `"mode":"local"`) {
+		t.Fatalf("/auth/me: %d %s", code, body)
+	}
+	if res, _ := c.Get(app + "/login.html"); res.StatusCode != http.StatusFound {
+		t.Errorf("login page while logged in: %d", res.StatusCode)
+	}
+
+	if res, _ := c.Get(app + "/auth/logout"); res.Header.Get("Location") != "/login.html" {
+		t.Fatalf("logout: %q", res.Header.Get("Location"))
+	}
+	if code, _ := get(t, c, app+"/api/logs"); code != http.StatusUnauthorized {
+		t.Fatal("session still valid after logout")
+	}
+}
+
+func TestLocalBasicAuthForScripts(t *testing.T) {
+	app, c := newLocalApp(t, authConfig{user: "admin", pass: "pw"})
+	req, _ := http.NewRequest(http.MethodGet, app+"/api/logs", nil)
+	req.SetBasicAuth("admin", "pw")
+	if res, _ := c.Do(req); res.StatusCode != http.StatusOK {
+		t.Fatalf("basic auth: %d", res.StatusCode)
+	}
+	req.SetBasicAuth("admin", "nope")
+	if res, _ := c.Do(req); res.StatusCode != http.StatusUnauthorized {
+		t.Fatalf("wrong basic auth: %d", res.StatusCode)
+	}
+}
+
+func TestLocalPasswordChangeEndsSessions(t *testing.T) {
+	dir := t.TempDir()
+	loginFailDelay = 0
+	echo := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {})
+	h1, _ := newAuth(authConfig{mode: "local", user: "admin", pass: "old", dataDir: dir}, echo)
+	h2, _ := newAuth(authConfig{mode: "local", user: "admin", pass: "new", dataDir: dir}, echo)
+	cookie := signCookie(h1.(*Local).key, session{User: "admin", Exp: 9999999999})
+	r, _ := http.NewRequest(http.MethodGet, "/", nil)
+	r.AddCookie(&http.Cookie{Name: sessionCookie, Value: cookie})
+	if _, ok := h1.(*Local).sessionUser(r); !ok {
+		t.Fatal("session refused with the same password")
+	}
+	if _, ok := h2.(*Local).sessionUser(r); ok {
+		t.Fatal("session kept after a password change")
+	}
+}
+
+func TestLocalLogo(t *testing.T) {
+	app, c := newLocalApp(t, authConfig{user: "admin", pass: "pw"})
+	if code, _ := get(t, c, app+"/auth/logo"); code != http.StatusNotFound {
+		t.Errorf("no LOGIN_LOGO: %d", code)
+	}
+	png := filepath.Join(t.TempDir(), "logo.png")
+	_ = os.WriteFile(png, []byte("\x89PNG\r\n\x1a\nfake"), 0o644)
+	app, c = newLocalApp(t, authConfig{user: "admin", pass: "pw", loginLogo: png})
+	res, _ := c.Get(app + "/auth/logo")
+	if res.StatusCode != http.StatusOK || res.Header.Get("Content-Type") != "image/png" {
+		t.Errorf("LOGIN_LOGO: %d %q", res.StatusCode, res.Header.Get("Content-Type"))
+	}
+}
+
+func TestLocalWithoutUserIsOpen(t *testing.T) {
+	if h, _ := newAuth(authConfig{mode: "local"}, http.NotFoundHandler()); h == nil || isLocal(h) {
+		t.Error("local mode without AUTH_USER should not protect anything")
+	}
+}
+
+func isLocal(h http.Handler) bool { _, ok := h.(*Local); return ok }

docker-compose.yml

@@ -14,15 +14,16 @@ services:
       VLOGS_URL: http://victorialogs:9428
       SYSLOG_PUBLIC_PORT: ${SYSLOG_PORT:-514}     # le port d'ecoute syslog par defaut (attention aux ports <1024)
       TZ: ${TZ:-Europe/Paris}
-      AUTH_MODE: ${AUTH_MODE:-local}   # local (Basic Auth ci-dessous) ou oidc
+      AUTH_MODE: ${AUTH_MODE:-local}   # local (page de connexion, compte ci-dessous) ou oidc
       AUTH_USER: ${AUTH_USER:-}   # vide = pas d'authentification, on delegue ca au reverse proxy traefik
       AUTH_PASS: ${AUTH_PASS:-}
+      LOGIN_LOGO: ${LOGIN_LOGO:-}     # PNG affiche sur la page de connexion (chemin dans le conteneur, voir volumes)
       OIDC_ISSUER: ${OIDC_ISSUER:-}
       OIDC_CLIENT_ID: ${OIDC_CLIENT_ID:-}
       OIDC_CLIENT_SECRET: ${OIDC_CLIENT_SECRET:-}
       OIDC_REDIRECT_URL: ${OIDC_REDIRECT_URL:-}
       OIDC_SCOPES: ${OIDC_SCOPES:-openid profile email}
-      OIDC_SESSION_TTL: ${OIDC_SESSION_TTL:-12h}
+      SESSION_TTL: ${SESSION_TTL:-${OIDC_SESSION_TTL:-12h}}   # duree de la session (local et oidc)
       RDNS: ${RDNS:-on}               # resol dns
       DNS_SERVER: ${DNS_SERVER:-}     # si resolv directe
       ALLOW_PURGE: ${ALLOW_PURGE:-true}
@@ -38,6 +39,8 @@ services:
       # logs systeme de l'hote, en lecture seule (source a activer dans Reglages > Sources)
       - /var/log:/host/var/log:ro                     # journal systemd persistant et fichiers texte
       - /run/log/journal:/host/run/log/journal:ro     # journal systemd volatile
+      # logo de la page de connexion, avec LOGIN_LOGO=/config/logo.png dans .env
+      # - ./logo.png:/config/logo.png:ro
     labels:
       logstream.exclude: "true"      # pas de collect des logs logstream
 

main.go

@@ -89,7 +89,9 @@ func main() {
 			clientSecret: os.Getenv("OIDC_CLIENT_SECRET"),
 			redirectURL:  os.Getenv("OIDC_REDIRECT_URL"),
 			scopes:       os.Getenv("OIDC_SCOPES"),
-			sessionTTL:   getenvDuration("OIDC_SESSION_TTL", 12*time.Hour),
+			// SESSION_TTL applies to both modes; OIDC_SESSION_TTL is its former name.
+			sessionTTL: getenvDuration("SESSION_TTL", getenvDuration("OIDC_SESSION_TTL", 12*time.Hour)),
+			loginLogo:  os.Getenv("LOGIN_LOGO"),
 		},
 		rdns:       getenvBool("RDNS", true),
 		dnsServer:  os.Getenv("DNS_SERVER"),

web/app.js

@@ -2103,7 +2103,7 @@ $('#range').value = store.get('range', '1h');
 if (!$('#range').value) $('#range').value = '1h';
 $('#severity').value = store.get('severity', '');
 
-// With OIDC login, show who is logged in and the log out button.
+// With a login (local or OIDC), show who is logged in and the log out button.
 fetch('/auth/me').then((res) => (res.ok ? res.json() : null)).then((me) => {
   if (!me || !me.user) return;
   const btn = $('#logoutBtn');

web/login.html

@@ -0,0 +1,95 @@
+<!doctype html>
+<html lang="en">
+<head>
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1">
+  <title>Logstream</title>
+  <link rel="icon" href="data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 32'%3E%3Crect width='32' height='32' rx='8' fill='%236366f1'/%3E%3Cpath d='M8 10h16M8 16h11M8 22h14' stroke='white' stroke-width='3' stroke-linecap='round'/%3E%3C/svg%3E">
+  <link rel="stylesheet" href="style.css">
+  <script>
+    // Same saved theme and language as the UI, applied before first paint.
+    try {
+      var t = localStorage.getItem('logstream.theme');
+      if (t === 'light' || t === 'dark') document.documentElement.dataset.theme = t;
+      var l = localStorage.getItem('logstream.lang');
+      if (l) document.documentElement.lang = l;
+    } catch (e) {}
+  </script>
+</head>
+<body class="login-page">
+  <div class="login-tools">
+    <div class="seg" role="radiogroup" id="langSwitch">
+      <button type="button" role="radio" data-lang="fr">FR</button>
+      <button type="button" role="radio" data-lang="en">EN</button>
+    </div>
+    <button id="themeBtn" class="icon-btn" type="button" data-i18n-title="theme" data-i18n-aria="theme">
+      <svg class="sun" viewBox="0 0 24 24"><circle cx="12" cy="12" r="4"/><path d="M12 2v2M12 20v2M4.9 4.9l1.4 1.4M17.7 17.7l1.4 1.4M2 12h2M20 12h2M4.9 19.1l1.4-1.4M17.7 6.3l1.4-1.4"/></svg>
+      <svg class="moon" viewBox="0 0 24 24"><path d="M21 12.8A9 9 0 1 1 11.2 3a7 7 0 0 0 9.8 9.8z"/></svg>
+    </button>
+  </div>
+
+  <main class="login-card">
+    <img id="logo" class="login-logo" src="auth/logo" alt="" hidden>
+    <div class="brand">
+      <svg viewBox="0 0 32 32" aria-hidden="true"><rect width="32" height="32" rx="8"/><path d="M8 10h16M8 16h11M8 22h14"/></svg>
+      <span>Logstream</span>
+    </div>
+    <p class="muted" data-i18n="intro">Sign in to view the logs.</p>
+
+    <form method="post" action="auth/login">
+      <input type="hidden" name="r" id="ret">
+      <label for="user" data-i18n="user">User</label>
+      <input id="user" name="user" type="text" autocomplete="username" autocapitalize="none" spellcheck="false" required autofocus>
+      <label for="pass" data-i18n="pass">Password</label>
+      <input id="pass" name="pass" type="password" autocomplete="current-password" required>
+      <p id="err" class="login-err" role="alert" data-i18n="error" hidden>Wrong user or password.</p>
+      <button class="btn primary" type="submit" data-i18n="submit">Sign in</button>
+    </form>
+  </main>
+
+  <script>
+    (function () {
+      var I18N = {
+        en: { intro: 'Sign in to view the logs.', user: 'User', pass: 'Password', submit: 'Sign in',
+              error: 'Wrong user or password.', theme: 'Light / dark theme' },
+        fr: { intro: 'Connectez-vous pour consulter les logs.', user: 'Utilisateur', pass: 'Mot de passe',
+              submit: 'Se connecter', error: 'Utilisateur ou mot de passe incorrect.', theme: 'Thème clair / sombre' },
+      };
+      function get(k) { try { return localStorage.getItem('logstream.' + k); } catch (e) { return null; } }
+      function set(k, v) { try { localStorage.setItem('logstream.' + k, v); } catch (e) {} }
+      var lang = get('lang');
+      if (!I18N[lang]) lang = /^fr\b/i.test(navigator.language || '') ? 'fr' : 'en';
+
+      function applyLang() {
+        var d = I18N[lang];
+        document.documentElement.lang = lang;
+        document.querySelectorAll('[data-i18n]').forEach(function (el) { el.textContent = d[el.dataset.i18n]; });
+        document.querySelectorAll('[data-i18n-title]').forEach(function (el) { el.title = d[el.dataset.i18nTitle]; });
+        document.querySelectorAll('[data-i18n-aria]').forEach(function (el) { el.setAttribute('aria-label', d[el.dataset.i18nAria]); });
+        document.querySelectorAll('#langSwitch [data-lang]').forEach(function (b) { b.setAttribute('aria-checked', String(b.dataset.lang === lang)); });
+      }
+      document.querySelectorAll('#langSwitch [data-lang]').forEach(function (b) {
+        b.addEventListener('click', function () { lang = b.dataset.lang; set('lang', lang); applyLang(); });
+      });
+
+      document.getElementById('themeBtn').addEventListener('click', function () {
+        var root = document.documentElement;
+        var dark = root.dataset.theme ? root.dataset.theme === 'dark' : matchMedia('(prefers-color-scheme: dark)').matches;
+        root.dataset.theme = dark ? 'light' : 'dark';
+        set('theme', root.dataset.theme);
+      });
+
+      var q = new URLSearchParams(location.search);
+      document.getElementById('ret').value = q.get('r') || '/';
+      document.getElementById('err').hidden = q.get('e') !== '1';
+
+      // LOGIN_LOGO: shown only when the server has one.
+      var logo = document.getElementById('logo');
+      logo.addEventListener('load', function () { logo.hidden = false; });
+      if (logo.complete && logo.naturalWidth) logo.hidden = false;
+
+      applyLang();
+    })();
+  </script>
+</body>
+</html>

web/style.css

@@ -672,3 +672,29 @@ input.switch:focus-visible { outline: 2px solid var(--accent); outline-offset: 2
   .tag-row .opts { grid-column: 1 / -1; grid-row: 2; flex-wrap: wrap; }
   .tag-row [data-del] { grid-column: 3; grid-row: 1; }
 }
+
+/* ---------- Login page (AUTH_MODE=local) ---------- */
+body.login-page {
+  min-height: 100vh; padding: 16px;
+  display: grid; place-items: center;
+}
+.login-tools { position: fixed; top: 12px; right: 16px; display: flex; align-items: center; gap: 8px; }
+.login-card {
+  width: 100%; max-width: 360px;
+  display: flex; flex-direction: column; align-items: center; gap: 10px;
+  padding: 32px 28px 28px;
+  background: var(--panel); border: 1px solid var(--border); border-radius: 14px; box-shadow: var(--shadow);
+}
+.login-logo { max-width: 200px; max-height: 96px; object-fit: contain; margin-bottom: 6px; }
+.login-card .brand { font-size: 20px; }
+.login-card .brand svg { width: 32px; height: 32px; }
+.login-card > p { margin: 0 0 8px; text-align: center; }
+.login-card form { width: 100%; display: flex; flex-direction: column; gap: 6px; }
+.login-card label { font-size: 13px; font-weight: 550; }
+.login-card input {
+  height: 38px; padding: 0 11px; margin-bottom: 6px;
+  border: 1px solid var(--border); border-radius: 9px; background: var(--bg);
+}
+.login-card input:focus { outline: 0; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
+.login-card .btn.primary { height: 38px; justify-content: center; margin-top: 6px; font-size: 14px; }
+.login-err { margin: 0; color: var(--sev-err); font-size: 13px; }