Add site-wide login gate protecting the whole app

Chat/memory/logs/models APIs were reachable without any auth even
though the app is deployed publicly behind Caddy HTTPS; only the
settings screen had a password. Add an optional SITE_PASSWORD-backed
session cookie gate in front of everything (settings included, on
top of its existing SETTINGS_PASSWORD), with a matching login screen
on the frontend. Stays fully backward compatible: with SITE_PASSWORD
unset the app behaves exactly as before.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

.claude/launch.json

@@ -6,6 +6,12 @@
       "runtimeExecutable": "npm",
       "runtimeArgs": ["--prefix", "frontend", "run", "dev"],
       "port": 5173
+    },
+    {
+      "name": "backend-dev",
+      "runtimeExecutable": "backend\\run_dev.cmd",
+      "runtimeArgs": [],
+      "port": 8000
     }
   ]
 }

CLAUDE.md

@@ -107,3 +107,5 @@ SQLite (playchat.db) + LiteLLM → 任意の LLM
 | `OPENAI_API_KEY` | — | OpenAI API キー |
 | `ANTHROPIC_API_KEY` | — | Anthropic API キー |
 | `OLLAMA_API_BASE` | `http://localhost:11434` | Ollama エンドポイント |
+| `SITE_PASSWORD` | — | サイト全体を保護する共有パスワード（未設定なら無認証） |
+| `SESSION_SECRET_KEY` | 起動毎に自動生成 | ログインセッション Cookie の署名鍵 |

backend/.env.example

@@ -21,6 +21,17 @@ DEBUG=false
 # HTTPS化していない環境ではBasic認証の資格情報が平文で流れるため、公開環境ではHTTPS化とセットで使うこと。
 SETTINGS_PASSWORD=
 
+# サイト全体（チャット含む全機能）を保護する簡易パスワード。SETTINGS_PASSWORDとは別物。
+# 未設定だとこれまで通りサイト全体が無認証で使える。外部公開する場合は必ず設定すること。
+SITE_PASSWORD=
+# セッションCookieの署名鍵。未設定でも動くが、その場合バックエンド再起動のたびに全員ログインし直しになる。
+# 公開環境では `openssl rand -hex 32` などで生成した値を設定しておくこと。
+SESSION_SECRET_KEY=
+# ローカルのhttp開発環境（HTTPS化していない）でログインが効かない場合のみ false にする。公開環境では変更しないこと。
+SESSION_COOKIE_SECURE=true
+# ログインセッションの有効日数
+SESSION_MAX_AGE_DAYS=30
+
 # Tavily Web検索（未設定だとweb_searchツールは何も検索せず空振りする）
 TAVILY_API_KEY=
 # 蓄積知識をシステムプロンプトに注入する際の最大件数

backend/app/api/auth.py

@@ -0,0 +1,50 @@
+import secrets
+
+from fastapi import APIRouter, HTTPException, Request, Response
+from pydantic import BaseModel
+
+from app.core.config import SESSION_COOKIE_SECURE, SESSION_MAX_AGE_DAYS, SITE_PASSWORD
+from app.core.site_auth import COOKIE_NAME, create_session_token, verify_session_token
+
+router = APIRouter(prefix="/api/auth", tags=["auth"])
+
+
+class LoginRequest(BaseModel):
+    password: str
+
+
+class AuthStatus(BaseModel):
+    required: bool
+    authenticated: bool
+
+
+@router.get("/status", response_model=AuthStatus)
+def status(request: Request):
+    if not SITE_PASSWORD:
+        return AuthStatus(required=False, authenticated=True)
+    token = request.cookies.get(COOKIE_NAME)
+    return AuthStatus(required=True, authenticated=bool(token and verify_session_token(token)))
+
+
+@router.post("/login", response_model=AuthStatus)
+def login(req: LoginRequest, response: Response):
+    if not SITE_PASSWORD:
+        raise HTTPException(status_code=403, detail="SITE_PASSWORD is not configured on the server")
+    if not secrets.compare_digest(req.password, SITE_PASSWORD):
+        raise HTTPException(status_code=401, detail="Invalid password")
+    response.set_cookie(
+        COOKIE_NAME,
+        create_session_token(),
+        max_age=SESSION_MAX_AGE_DAYS * 86400,
+        httponly=True,
+        secure=SESSION_COOKIE_SECURE,
+        samesite="lax",
+        path="/",
+    )
+    return AuthStatus(required=True, authenticated=True)
+
+
+@router.post("/logout", response_model=AuthStatus)
+def logout(response: Response):
+    response.delete_cookie(COOKIE_NAME, path="/")
+    return AuthStatus(required=bool(SITE_PASSWORD), authenticated=False)

backend/app/core/config.py

@@ -1,5 +1,6 @@
 from dotenv import load_dotenv
 import os
+import secrets
 
 load_dotenv()
 
@@ -12,6 +13,14 @@ DEBUG: bool = os.getenv("DEBUG", "false").lower() in ("1", "true", "yes")
 # GUI設定画面（/api/settings）を保護する簡易パスワード。未設定の場合、設定画面は常に403で拒否する。
 SETTINGS_PASSWORD: str | None = os.getenv("SETTINGS_PASSWORD")
 
+# サイト全体（設定画面以外の全API）を保護する簡易パスワード。未設定の場合はこれまで通り無認証で動く。
+SITE_PASSWORD: str | None = os.getenv("SITE_PASSWORD")
+# セッションCookieの署名に使う秘密鍵。未設定なら起動毎に使い捨てキーを生成する（バックエンド再起動でログインし直しになる）。
+SESSION_SECRET_KEY: str = os.getenv("SESSION_SECRET_KEY") or secrets.token_hex(32)
+# ローカルのhttp開発環境ではSecure Cookieが送信されないため、その場合のみfalseにする。公開環境では必ずtrueのままにすること。
+SESSION_COOKIE_SECURE: bool = os.getenv("SESSION_COOKIE_SECURE", "true").lower() in ("1", "true", "yes")
+SESSION_MAX_AGE_DAYS: int = int(os.getenv("SESSION_MAX_AGE_DAYS", "30"))
+
 # メッセージへの自動タグ付けに使うモデル（未設定ならDEFAULT_MODELを使用）
 TAGGING_MODEL: str | None = os.getenv("TAGGING_MODEL")
 

backend/app/core/site_auth.py

@@ -0,0 +1,40 @@
+import hashlib
+import hmac
+import time
+
+from fastapi import HTTPException, Request
+
+from app.core.config import SESSION_MAX_AGE_DAYS, SESSION_SECRET_KEY, SITE_PASSWORD
+
+COOKIE_NAME = "playchat_session"
+
+
+def _sign(payload: str) -> str:
+    return hmac.new(SESSION_SECRET_KEY.encode(), payload.encode(), hashlib.sha256).hexdigest()
+
+
+def create_session_token() -> str:
+    issued_at = str(int(time.time()))
+    return f"{issued_at}.{_sign(issued_at)}"
+
+
+def verify_session_token(token: str) -> bool:
+    issued_at, _, signature = token.partition(".")
+    if not issued_at or not signature:
+        return False
+    if not hmac.compare_digest(_sign(issued_at), signature):
+        return False
+    age_seconds = time.time() - int(issued_at)
+    return 0 <= age_seconds <= SESSION_MAX_AGE_DAYS * 86400
+
+
+def require_site_session(request: Request) -> None:
+    """サイト全体（設定画面以外の全API）を保護するセッションCookie認証。
+
+    SITE_PASSWORD が未設定の場合は既存のローカル開発体験を壊さないよう常に通す。
+    """
+    if not SITE_PASSWORD:
+        return
+    token = request.cookies.get(COOKIE_NAME)
+    if not token or not verify_session_token(token):
+        raise HTTPException(status_code=401, detail="Login required")

backend/app/main.py

@@ -1,14 +1,16 @@
 import asyncio
 from contextlib import asynccontextmanager
 
-from fastapi import FastAPI
+from fastapi import Depends, FastAPI
 from fastapi.middleware.cors import CORSMiddleware
 
+from app.api import auth as auth_api
 from app.api import chat, logs, memory, system
 from app.api import models as models_api
 from app.api import settings as settings_api
 from app.core import settings_store
 from app.core.config import CORS_ORIGINS
+from app.core.site_auth import require_site_session
 from app.core.discord.discord_bot import start_discord_bot
 from app.core.discord.scheduler import start_scheduler
 from app.core.memory_kb.word_memory import seed_from_history
@@ -88,12 +90,13 @@ app.add_middleware(
 )
 
 
-app.include_router(chat.router)
-app.include_router(memory.router)
-app.include_router(logs.router)
-app.include_router(system.router)
-app.include_router(settings_api.router)
-app.include_router(models_api.router)
+app.include_router(auth_api.router)
+app.include_router(chat.router, dependencies=[Depends(require_site_session)])
+app.include_router(memory.router, dependencies=[Depends(require_site_session)])
+app.include_router(logs.router, dependencies=[Depends(require_site_session)])
+app.include_router(system.router, dependencies=[Depends(require_site_session)])
+app.include_router(settings_api.router, dependencies=[Depends(require_site_session)])
+app.include_router(models_api.router, dependencies=[Depends(require_site_session)])
 
 
 @app.get("/health")

backend/run_dev.cmd

@@ -0,0 +1,6 @@
+@echo off
+rem SSLKEYLOGFILE がこのマシンのTLS監視プロキシの名前付きパイプを指していると
+rem litellm(OpenSSLを直接ロード)が OPENSSL_Uplink エラーで起動時にクラッシュするため、
+rem このコマンドの実行中だけ unset する（CLAUDE.md の「ローカル開発環境メモ」参照）。
+set SSLKEYLOGFILE=
+uv run --directory backend uvicorn app.main:app --reload --port 8000

frontend/src/App.vue

@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { ref } from 'vue'
+import { onMounted, onUnmounted, ref } from 'vue'
 import SessionList from './components/SessionList.vue'
 import ChatWindow from './components/ChatWindow.vue'
 import MessageInput from './components/MessageInput.vue'
@@ -10,6 +10,10 @@ import ToastList from './components/ToastList.vue'
 import MemoryMonitor from './components/MemoryMonitor.vue'
 import Clock from './components/Clock.vue'
 import WordPool from './components/WordPool.vue'
+import LoginGate from './components/LoginGate.vue'
+import { useAuthStore } from './stores/auth'
+
+const authStore = useAuthStore()
 
 type SidePanel = 'none' | 'logs' | 'settings'
 const activePanel = ref<SidePanel>('none')
@@ -17,42 +21,61 @@ const activePanel = ref<SidePanel>('none')
 function togglePanel(panel: SidePanel) {
   activePanel.value = activePanel.value === panel ? 'none' : panel
 }
+
+function handleUnauthorized() {
+  authStore.markUnauthenticated()
+}
+
+onMounted(() => {
+  authStore.checkStatus()
+  window.addEventListener('playchat:unauthorized', handleUnauthorized)
+})
+onUnmounted(() => {
+  window.removeEventListener('playchat:unauthorized', handleUnauthorized)
+})
 </script>
 
 <template>
-  <div class="app">
-    <div class="sidebar">
-      <SessionList />
-      <MemoryMonitor />
-      <WordPool />
-    </div>
-    <div class="main">
-      <header>
-        <span class="title">PlayChat</span>
-        <ModelSelector />
-        <Clock />
-        <button class="log-toggle" :class="{ active: activePanel === 'settings' }" @click="togglePanel('settings')">
-          設定
-        </button>
-        <button class="log-toggle" :class="{ active: activePanel === 'logs' }" @click="togglePanel('logs')">
-          ログ
-        </button>
-      </header>
-      <div class="body">
-        <div class="chat-pane">
-          <ChatWindow />
-          <MessageInput />
-        </div>
-        <div v-if="activePanel === 'logs'" class="log-pane">
-          <LogViewer />
-        </div>
-        <div v-else-if="activePanel === 'settings'" class="log-pane">
-          <SettingsPanel />
+  <template v-if="authStore.loading" />
+  <LoginGate v-else-if="authStore.required && !authStore.authenticated" />
+  <template v-else>
+    <div class="app">
+      <div class="sidebar">
+        <SessionList />
+        <MemoryMonitor />
+        <WordPool />
+      </div>
+      <div class="main">
+        <header>
+          <span class="title">PlayChat</span>
+          <ModelSelector />
+          <Clock />
+          <button class="log-toggle" :class="{ active: activePanel === 'settings' }" @click="togglePanel('settings')">
+            設定
+          </button>
+          <button class="log-toggle" :class="{ active: activePanel === 'logs' }" @click="togglePanel('logs')">
+            ログ
+          </button>
+          <button v-if="authStore.required" class="log-toggle" @click="authStore.logout()">
+            ログアウト
+          </button>
+        </header>
+        <div class="body">
+          <div class="chat-pane">
+            <ChatWindow />
+            <MessageInput />
+          </div>
+          <div v-if="activePanel === 'logs'" class="log-pane">
+            <LogViewer />
+          </div>
+          <div v-else-if="activePanel === 'settings'" class="log-pane">
+            <SettingsPanel />
+          </div>
         </div>
       </div>
     </div>
-  </div>
-  <ToastList />
+    <ToastList />
+  </template>
 </template>
 
 <style>

frontend/src/api/client.ts

@@ -34,6 +34,7 @@ async function parseJson<T>(res: Response, label: string): Promise<T> {
     throw new Error(`${label}: バックエンドに接続できません (${res.status} ${res.statusText})`)
   }
   if (!res.ok) {
+    if (res.status === 401) window.dispatchEvent(new Event('playchat:unauthorized'))
     const body = await res.json().catch(() => ({}))
     throw new Error(`${label}: ${body.detail ?? res.statusText}`)
   }
@@ -81,6 +82,29 @@ export async function deleteLog(logId: number): Promise<void> {
   await fetch(`${BASE}/logs/${logId}`, { method: 'DELETE' })
 }
 
+export interface AuthStatus {
+  required: boolean
+  authenticated: boolean
+}
+
+export async function fetchAuthStatus(): Promise<AuthStatus> {
+  const res = await fetch(`${BASE}/api/auth/status`)
+  return parseJson<AuthStatus>(res, '認証状態取得')
+}
+
+export async function login(password: string): Promise<AuthStatus> {
+  const res = await fetch(`${BASE}/api/auth/login`, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ password }),
+  })
+  return parseJson<AuthStatus>(res, 'ログイン')
+}
+
+export async function logout(): Promise<void> {
+  await fetch(`${BASE}/api/auth/logout`, { method: 'POST' })
+}
+
 export interface SettingEntry {
   key: string
   is_set: boolean

frontend/src/components/LoginGate.vue

@@ -0,0 +1,56 @@
+<script setup lang="ts">
+import { ref } from 'vue'
+import { useAuthStore } from '../stores/auth'
+
+const store = useAuthStore()
+const passwordInput = ref('')
+
+async function submit() {
+  const ok = await store.login(passwordInput.value)
+  if (ok) passwordInput.value = ''
+}
+</script>
+
+<template>
+  <div class="login-gate">
+    <form class="card" @submit.prevent="submit">
+      <span class="title">PlayChat</span>
+      <p class="hint">サイトを利用するにはパスワードが必要です。</p>
+      <input
+        v-model="passwordInput"
+        type="password"
+        placeholder="パスワード"
+        autocomplete="current-password"
+        autofocus
+      />
+      <button type="submit" :disabled="store.loading || !passwordInput">
+        {{ store.loading ? '確認中...' : 'ログイン' }}
+      </button>
+      <p v-if="store.error" class="error">{{ store.error }}</p>
+    </form>
+  </div>
+</template>
+
+<style scoped>
+.login-gate {
+  height: 100vh; display: flex; align-items: center; justify-content: center;
+  background: #111;
+}
+.card {
+  display: flex; flex-direction: column; gap: 10px;
+  width: 280px; padding: 24px; background: #1a1a1a;
+  border: 1px solid #2a2a2a; border-radius: 10px;
+}
+.title { font-size: 18px; font-weight: 600; color: #fff; }
+.hint { font-size: 12px; color: #888; }
+input {
+  background: #2a2a2a; color: #eee; border: 1px solid #444;
+  border-radius: 6px; padding: 8px 10px; font-size: 13px; width: 100%;
+}
+button {
+  background: #1d3557; color: #93c5fd; border: 1px solid #2563eb;
+  border-radius: 6px; padding: 8px 10px; font-size: 13px; cursor: pointer;
+}
+button:disabled { opacity: 0.5; cursor: default; }
+.error { font-size: 12px; color: #f87171; }
+</style>

frontend/src/stores/auth.ts

@@ -0,0 +1,51 @@
+import { defineStore } from 'pinia'
+import { ref } from 'vue'
+import { fetchAuthStatus, login as loginApi, logout as logoutApi } from '../api/client'
+
+export const useAuthStore = defineStore('auth', () => {
+  const required = ref(false)
+  const authenticated = ref(false)
+  const loading = ref(true)
+  const error = ref<string | null>(null)
+
+  async function checkStatus(): Promise<void> {
+    loading.value = true
+    try {
+      const status = await fetchAuthStatus()
+      required.value = status.required
+      authenticated.value = status.authenticated
+    } catch (e) {
+      error.value = e instanceof Error ? e.message : 'エラーが発生しました'
+    } finally {
+      loading.value = false
+    }
+  }
+
+  async function login(password: string): Promise<boolean> {
+    loading.value = true
+    error.value = null
+    try {
+      const status = await loginApi(password)
+      required.value = status.required
+      authenticated.value = status.authenticated
+      return true
+    } catch (e) {
+      authenticated.value = false
+      error.value = e instanceof Error ? e.message : 'エラーが発生しました'
+      return false
+    } finally {
+      loading.value = false
+    }
+  }
+
+  async function logout(): Promise<void> {
+    await logoutApi().catch(() => {})
+    authenticated.value = false
+  }
+
+  function markUnauthenticated(): void {
+    authenticated.value = false
+  }
+
+  return { required, authenticated, loading, error, checkStatus, login, logout, markUnauthenticated }
+})