fix: Address code review feedback and add SSO documentation

- Remove duplicate route registration - Fix return type for OAuth callback handler - Add OAuth SSO configuration documentation - Add security comments for OAuth query parameters Co-authored-by: samanhappy <2755122+samanhappy@users.noreply.github.com>
feat: Add OAuth 2.0 / OIDC SSO login support
2025-12-31 20:00:00 -05:00 · 2025-12-31 15:16:19 +00:00 · 2025-12-31 15:08:10 +00:00 · 2025-12-31 14:51:49 +00:00
17 changed files with 1789 additions and 54 deletions
--- a/docs/configuration/oauth-sso.mdx
+++ b/docs/configuration/oauth-sso.mdx
@@ -0,0 +1,218 @@
+---
+title: OAuth SSO Configuration
+description: Configure OAuth 2.0 / OIDC Single Sign-On for MCPHub
+---
+
+# OAuth SSO Configuration
+
+MCPHub supports OAuth 2.0 / OIDC Single Sign-On (SSO) for enterprise authentication, allowing users to log in using their existing identity provider accounts (Google, Microsoft, GitHub, or custom OIDC providers).
+
+## Overview
+
+SSO support allows:
+- Login via major providers (Google, Microsoft, GitHub)
+- Custom OIDC provider integration
+- Auto-provisioning of new users from OAuth profiles
+- Role mapping from provider claims/groups
+- Hybrid auth (both SSO and local username/password)
+
+## Configuration
+
+Add the `oauthSSO` section to your `mcp_settings.json` under `systemConfig`:
+
+```json
+{
+  "systemConfig": {
+    "oauthSSO": {
+      "enabled": true,
+      "allowLocalAuth": true,
+      "callbackBaseUrl": "https://your-mcphub-domain.com",
+      "providers": [
+        {
+          "id": "google",
+          "name": "Google",
+          "type": "google",
+          "clientId": "your-google-client-id",
+          "clientSecret": "your-google-client-secret"
+        },
+        {
+          "id": "github",
+          "name": "GitHub",
+          "type": "github",
+          "clientId": "your-github-client-id",
+          "clientSecret": "your-github-client-secret"
+        },
+        {
+          "id": "microsoft",
+          "name": "Microsoft",
+          "type": "microsoft",
+          "clientId": "your-microsoft-client-id",
+          "clientSecret": "your-microsoft-client-secret"
+        }
+      ]
+    }
+  }
+}
+```
+
+## Provider Configuration
+
+### Google
+
+1. Go to [Google Cloud Console](https://console.cloud.google.com/)
+2. Create a new project or select existing one
+3. Navigate to "APIs & Services" → "Credentials"
+4. Create OAuth 2.0 Client ID (Web application)
+5. Add authorized redirect URI: `https://your-domain/api/auth/sso/google/callback`
+6. Copy Client ID and Client Secret
+
+```json
+{
+  "id": "google",
+  "name": "Google",
+  "type": "google",
+  "clientId": "YOUR_GOOGLE_CLIENT_ID.apps.googleusercontent.com",
+  "clientSecret": "YOUR_GOOGLE_CLIENT_SECRET"
+}
+```
+
+### GitHub
+
+1. Go to [GitHub Developer Settings](https://github.com/settings/developers)
+2. Click "New OAuth App"
+3. Set Authorization callback URL: `https://your-domain/api/auth/sso/github/callback`
+4. Copy Client ID and generate Client Secret
+
+```json
+{
+  "id": "github",
+  "name": "GitHub",
+  "type": "github",
+  "clientId": "YOUR_GITHUB_CLIENT_ID",
+  "clientSecret": "YOUR_GITHUB_CLIENT_SECRET"
+}
+```
+
+### Microsoft (Azure AD)
+
+1. Go to [Azure Portal](https://portal.azure.com/) → Azure Active Directory
+2. Navigate to "App registrations" → "New registration"
+3. Add redirect URI: `https://your-domain/api/auth/sso/microsoft/callback`
+4. Under "Certificates & secrets", create a new client secret
+5. Copy Application (client) ID and client secret value
+
+```json
+{
+  "id": "microsoft",
+  "name": "Microsoft",
+  "type": "microsoft",
+  "clientId": "YOUR_AZURE_CLIENT_ID",
+  "clientSecret": "YOUR_AZURE_CLIENT_SECRET"
+}
+```
+
+### Custom OIDC Provider
+
+For other OIDC-compatible identity providers:
+
+```json
+{
+  "id": "custom-idp",
+  "name": "Corporate SSO",
+  "type": "oidc",
+  "issuerUrl": "https://idp.example.com",
+  "authorizationUrl": "https://idp.example.com/oauth2/authorize",
+  "tokenUrl": "https://idp.example.com/oauth2/token",
+  "userInfoUrl": "https://idp.example.com/oauth2/userinfo",
+  "clientId": "YOUR_CLIENT_ID",
+  "clientSecret": "YOUR_CLIENT_SECRET",
+  "scopes": ["openid", "email", "profile"],
+  "attributeMapping": {
+    "username": "preferred_username",
+    "email": "email",
+    "name": "name"
+  }
+}
+```
+
+## Role Mapping
+
+Configure automatic admin role assignment based on provider claims:
+
+```json
+{
+  "id": "google",
+  "name": "Google",
+  "type": "google",
+  "clientId": "...",
+  "clientSecret": "...",
+  "roleMapping": {
+    "adminClaim": "groups",
+    "adminValues": ["mcphub-admins", "engineering-leads"],
+    "defaultIsAdmin": false
+  }
+}
+```
+
+This configuration:
+- Checks the `groups` claim in the user's profile
+- Grants admin access if any value matches `mcphub-admins` or `engineering-leads`
+- Non-matching users get regular (non-admin) access
+
+## Configuration Options
+
+### Global Options
+
+| Option | Type | Default | Description |
+|--------|------|---------|-------------|
+| `enabled` | boolean | `false` | Enable/disable SSO globally |
+| `allowLocalAuth` | boolean | `true` | Allow local username/password auth alongside SSO |
+| `callbackBaseUrl` | string | auto-detected | Base URL for OAuth callbacks |
+
+### Provider Options
+
+| Option | Type | Required | Description |
+|--------|------|----------|-------------|
+| `id` | string | Yes | Unique identifier for the provider |
+| `name` | string | Yes | Display name shown on login page |
+| `type` | string | Yes | Provider type: `google`, `github`, `microsoft`, or `oidc` |
+| `clientId` | string | Yes | OAuth client ID from the provider |
+| `clientSecret` | string | Yes | OAuth client secret from the provider |
+| `enabled` | boolean | No | Enable/disable this specific provider (default: true) |
+| `scopes` | string[] | No | OAuth scopes to request |
+| `autoProvision` | boolean | No | Auto-create users on first SSO login (default: true) |
+| `allowLinking` | boolean | No | Allow existing users to link their accounts (default: true) |
+
+### Custom OIDC Options (type: "oidc")
+
+| Option | Type | Required | Description |
+|--------|------|----------|-------------|
+| `issuerUrl` | string | No | OIDC issuer URL for discovery |
+| `authorizationUrl` | string | Yes | OAuth authorization endpoint |
+| `tokenUrl` | string | Yes | OAuth token endpoint |
+| `userInfoUrl` | string | Yes | OIDC userinfo endpoint |
+| `attributeMapping` | object | No | Map provider claims to user attributes |
+
+## Security Notes
+
+1. **PKCE Support**: MCPHub uses PKCE (Proof Key for Code Exchange) for all providers except GitHub (which doesn't support it)
+2. **State Parameter**: A cryptographically random state is generated for each login to prevent CSRF attacks
+3. **Token Storage**: OAuth tokens from providers are not stored; only MCPHub's JWT is issued after successful authentication
+4. **Rate Limiting**: Consider implementing rate limiting at infrastructure level (reverse proxy) for SSO endpoints
+
+## Troubleshooting
+
+### Common Issues
+
+1. **"OAuth provider not found"**: Check that the provider is enabled and configured correctly
+2. **"Invalid or expired OAuth state"**: The login attempt took too long (>10 minutes) or was a replay attack
+3. **"Could not determine username"**: The provider didn't return expected user attributes; check `attributeMapping`
+4. **"User account not found and auto-provisioning is disabled"**: Set `autoProvision: true` or pre-create the user
+
+### Debug Mode
+
+Enable debug logging by setting the `DEBUG` environment variable:
+
+```bash
+DEBUG=oauth* node dist/index.js
+```
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -8,6 +8,7 @@ import { SettingsProvider } from './contexts/SettingsContext';
 import MainLayout from './layouts/MainLayout';
 import ProtectedRoute from './components/ProtectedRoute';
 import LoginPage from './pages/LoginPage';
+import SSOCallbackPage from './pages/SSOCallbackPage';
 import DashboardPage from './pages/Dashboard';
 import ServersPage from './pages/ServersPage';
 import GroupsPage from './pages/GroupsPage';
@@ -35,6 +36,7 @@ function App() {
                <Routes>
                  {/* 公共路由 */}
                  <Route path="/login" element={<LoginPage />} />
+                  <Route path="/sso-callback" element={<SSOCallbackPage />} />

                  {/* 受保护的路由，使用 MainLayout 作为布局容器 */}
                  <Route element={<ProtectedRoute />}>
--- a/frontend/src/pages/LoginPage.tsx
+++ b/frontend/src/pages/LoginPage.tsx
@@ -1,11 +1,12 @@
-import React, { useState, useMemo, useCallback } from 'react';
+import React, { useState, useMemo, useCallback, useEffect } from 'react';
 import { useLocation, useNavigate } from 'react-router-dom';
 import { useTranslation } from 'react-i18next';
 import { useAuth } from '../contexts/AuthContext';
-import { getToken } from '../services/authService';
+import { getToken, getSSOConfig, initiateSSOLogin } from '../services/authService';
 import ThemeSwitch from '@/components/ui/ThemeSwitch';
 import LanguageSwitch from '@/components/ui/LanguageSwitch';
 import DefaultPasswordWarningModal from '@/components/ui/DefaultPasswordWarningModal';
+import { SSOProvider } from '../types';

 const sanitizeReturnUrl = (value: string | null): string | null => {
  if (!value) {
@@ -29,6 +30,44 @@ const sanitizeReturnUrl = (value: string | null): string | null => {
  }
 };

+// Provider icons (SVG)
+const ProviderIcon: React.FC<{ type: string; className?: string }> = ({ type, className = 'w-5 h-5' }) => {
+  switch (type) {
+    case 'google':
+      return (
+        <svg className={className} viewBox="0 0 24 24" fill="currentColor">
+          <path d="M22.56 12.25c0-.78-.07-1.53-.2-2.25H12v4.26h5.92c-.26 1.37-1.04 2.53-2.21 3.31v2.77h3.57c2.08-1.92 3.28-4.74 3.28-8.09z" fill="#4285F4"/>
+          <path d="M12 23c2.97 0 5.46-.98 7.28-2.66l-3.57-2.77c-.98.66-2.23 1.06-3.71 1.06-2.86 0-5.29-1.93-6.16-4.53H2.18v2.84C3.99 20.53 7.7 23 12 23z" fill="#34A853"/>
+          <path d="M5.84 14.09c-.22-.66-.35-1.36-.35-2.09s.13-1.43.35-2.09V7.07H2.18C1.43 8.55 1 10.22 1 12s.43 3.45 1.18 4.93l2.85-2.22.81-.62z" fill="#FBBC05"/>
+          <path d="M12 5.38c1.62 0 3.06.56 4.21 1.64l3.15-3.15C17.45 2.09 14.97 1 12 1 7.7 1 3.99 3.47 2.18 7.07l3.66 2.84c.87-2.6 3.3-4.53 6.16-4.53z" fill="#EA4335"/>
+        </svg>
+      );
+    case 'github':
+      return (
+        <svg className={className} viewBox="0 0 24 24" fill="currentColor">
+          <path d="M12 0C5.37 0 0 5.37 0 12c0 5.31 3.435 9.795 8.205 11.385.6.105.825-.255.825-.57 0-.285-.015-1.23-.015-2.235-3.015.555-3.795-.735-4.035-1.41-.135-.345-.72-1.41-1.23-1.695-.42-.225-1.02-.78-.015-.795.945-.015 1.62.87 1.845 1.23 1.08 1.815 2.805 1.305 3.495.99.105-.78.42-1.305.765-1.605-2.67-.3-5.46-1.335-5.46-5.925 0-1.305.465-2.385 1.23-3.225-.12-.3-.54-1.53.12-3.18 0 0 1.005-.315 3.3 1.23.96-.27 1.98-.405 3-.405s2.04.135 3 .405c2.295-1.56 3.3-1.23 3.3-1.23.66 1.65.24 2.88.12 3.18.765.84 1.23 1.905 1.23 3.225 0 4.605-2.805 5.625-5.475 5.925.435.375.81 1.095.81 2.22 0 1.605-.015 2.895-.015 3.3 0 .315.225.69.825.57A12.02 12.02 0 0024 12c0-6.63-5.37-12-12-12z"/>
+        </svg>
+      );
+    case 'microsoft':
+      return (
+        <svg className={className} viewBox="0 0 24 24" fill="currentColor">
+          <path fill="#F25022" d="M1 1h10v10H1z"/>
+          <path fill="#00A4EF" d="M1 13h10v10H1z"/>
+          <path fill="#7FBA00" d="M13 1h10v10H13z"/>
+          <path fill="#FFB900" d="M13 13h10v10H13z"/>
+        </svg>
+      );
+    default:
+      // Generic OAuth/OIDC icon
+      return (
+        <svg className={className} viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+          <circle cx="12" cy="12" r="10"/>
+          <path d="M12 6v6l4 2"/>
+        </svg>
+      );
+  }
+};
+
 const LoginPage: React.FC = () => {
  const { t } = useTranslation();
  const [username, setUsername] = useState('');
@@ -36,6 +75,9 @@ const LoginPage: React.FC = () => {
  const [error, setError] = useState<string | null>(null);
  const [loading, setLoading] = useState(false);
  const [showDefaultPasswordWarning, setShowDefaultPasswordWarning] = useState(false);
+  const [ssoProviders, setSsoProviders] = useState<SSOProvider[]>([]);
+  const [ssoEnabled, setSsoEnabled] = useState(false);
+  const [allowLocalAuth, setAllowLocalAuth] = useState(true);
  const { login } = useAuth();
  const location = useLocation();
  const navigate = useNavigate();
@@ -44,6 +86,17 @@ const LoginPage: React.FC = () => {
    return sanitizeReturnUrl(params.get('returnUrl'));
  }, [location.search]);

+  // Load SSO configuration on mount
+  useEffect(() => {
+    const loadSSOConfig = async () => {
+      const config = await getSSOConfig();
+      setSsoEnabled(config.enabled);
+      setSsoProviders(config.providers);
+      setAllowLocalAuth(config.allowLocalAuth);
+    };
+    loadSSOConfig();
+  }, []);
+
  const isServerUnavailableError = useCallback((message?: string) => {
    if (!message) return false;
    const normalized = message.toLowerCase();
@@ -137,6 +190,10 @@ const LoginPage: React.FC = () => {
    }
  };

+  const handleSSOLogin = (providerId: string) => {
+    initiateSSOLogin(providerId, returnUrl || undefined);
+  };
+
  const handleCloseWarning = () => {
    setShowDefaultPasswordWarning(false);
    redirectAfterLogin();
@@ -193,58 +250,100 @@ const LoginPage: React.FC = () => {
          <div className="login-card relative w-full rounded-2xl border border-white/10 bg-white/60 p-8 shadow-xl backdrop-blur-md transition dark:border-white/10 dark:bg-gray-900/60">
            <div className="absolute -top-24 right-12 h-40 w-40 -translate-y-6 rounded-full bg-indigo-500/30 blur-3xl" />
            <div className="absolute -bottom-24 -left-12 h-40 w-40 translate-y-6 rounded-full bg-cyan-500/20 blur-3xl" />
-            <form className="mt-4 space-y-4" onSubmit={handleSubmit}>
-              <div className="space-y-4">
-                <div>
-                  <label htmlFor="username" className="sr-only">
-                    {t('auth.username')}
-                  </label>
-                  <input
-                    id="username"
-                    name="username"
-                    type="text"
-                    autoComplete="username"
-                    required
-                    className="login-input appearance-none relative block w-full rounded-md border border-gray-300/60 bg-white/70 px-3 py-3 text-gray-900 shadow-sm outline-none ring-0 transition-all placeholder:text-gray-500 focus:border-indigo-500 focus:ring-2 focus:ring-indigo-500 dark:border-gray-700/60 dark:bg-gray-800/70 dark:text-white dark:placeholder:text-gray-400"
-                    placeholder={t('auth.username')}
-                    value={username}
-                    onChange={(e) => setUsername(e.target.value)}
-                  />
-                </div>
-                <div>
-                  <label htmlFor="password" className="sr-only">
-                    {t('auth.password')}
-                  </label>
-                  <input
-                    id="password"
-                    name="password"
-                    type="password"
-                    autoComplete="current-password"
-                    required
-                    className="login-input appearance-none relative block w-full rounded-md border border-gray-300/60 bg-white/70 px-3 py-3 text-gray-900 shadow-sm outline-none ring-0 transition-all placeholder:text-gray-500 focus:border-indigo-500 focus:ring-2 focus:ring-indigo-500 dark:border-gray-700/60 dark:bg-gray-800/70 dark:text-white dark:placeholder:text-gray-400"
-                    placeholder={t('auth.password')}
-                    value={password}
-                    onChange={(e) => setPassword(e.target.value)}
-                  />
-                </div>
-              </div>

-              {error && (
-                <div className="error-box rounded border border-red-500/20 bg-red-500/10 p-2 text-center text-sm text-red-600 dark:text-red-400">
-                  {error}
-                </div>
-              )}
-
-              <div>
-                <button
-                  type="submit"
-                  disabled={loading}
-                  className="login-button btn-primary group relative flex w-full items-center justify-center rounded-md border border-transparent bg-indigo-600 px-4 py-2 text-sm font-medium text-white transition-all hover:bg-indigo-700 focus:outline-none focus:ring-2 focus:ring-indigo-500 focus:ring-offset-2 disabled:cursor-not-allowed disabled:opacity-70"
-                >
-                  {loading ? t('auth.loggingIn') : t('auth.login')}
-                </button>
+            {/* SSO Buttons */}
+            {ssoEnabled && ssoProviders.length > 0 && (
+              <div className="space-y-3 mb-6">
+                {ssoProviders.map((provider) => (
+                  <button
+                    key={provider.id}
+                    type="button"
+                    onClick={() => handleSSOLogin(provider.id)}
+                    className="sso-button group relative flex w-full items-center justify-center gap-3 rounded-md border border-gray-300/60 bg-white/80 px-4 py-2.5 text-sm font-medium text-gray-700 shadow-sm transition-all hover:bg-gray-50 hover:border-gray-400/60 focus:outline-none focus:ring-2 focus:ring-indigo-500 focus:ring-offset-2 dark:border-gray-600/60 dark:bg-gray-800/80 dark:text-gray-200 dark:hover:bg-gray-700/80"
+                  >
+                    <ProviderIcon type={provider.type} />
+                    <span>{t('auth.continueWith', { provider: provider.name })}</span>
+                  </button>
+                ))}
+                
+                {/* Divider - only show if local auth is also allowed */}
+                {allowLocalAuth && (
+                  <div className="relative my-4">
+                    <div className="absolute inset-0 flex items-center">
+                      <div className="w-full border-t border-gray-300/60 dark:border-gray-600/60" />
+                    </div>
+                    <div className="relative flex justify-center text-sm">
+                      <span className="px-2 bg-white/60 text-gray-500 dark:bg-gray-900/60 dark:text-gray-400">
+                        {t('auth.orContinueWith')}
+                      </span>
+                    </div>
+                  </div>
+                )}
              </div>
-            </form>
+            )}
+
+            {/* Local auth form - only show if allowed */}
+            {allowLocalAuth && (
+              <form className="mt-4 space-y-4" onSubmit={handleSubmit}>
+                <div className="space-y-4">
+                  <div>
+                    <label htmlFor="username" className="sr-only">
+                      {t('auth.username')}
+                    </label>
+                    <input
+                      id="username"
+                      name="username"
+                      type="text"
+                      autoComplete="username"
+                      required
+                      className="login-input appearance-none relative block w-full rounded-md border border-gray-300/60 bg-white/70 px-3 py-3 text-gray-900 shadow-sm outline-none ring-0 transition-all placeholder:text-gray-500 focus:border-indigo-500 focus:ring-2 focus:ring-indigo-500 dark:border-gray-700/60 dark:bg-gray-800/70 dark:text-white dark:placeholder:text-gray-400"
+                      placeholder={t('auth.username')}
+                      value={username}
+                      onChange={(e) => setUsername(e.target.value)}
+                    />
+                  </div>
+                  <div>
+                    <label htmlFor="password" className="sr-only">
+                      {t('auth.password')}
+                    </label>
+                    <input
+                      id="password"
+                      name="password"
+                      type="password"
+                      autoComplete="current-password"
+                      required
+                      className="login-input appearance-none relative block w-full rounded-md border border-gray-300/60 bg-white/70 px-3 py-3 text-gray-900 shadow-sm outline-none ring-0 transition-all placeholder:text-gray-500 focus:border-indigo-500 focus:ring-2 focus:ring-indigo-500 dark:border-gray-700/60 dark:bg-gray-800/70 dark:text-white dark:placeholder:text-gray-400"
+                      placeholder={t('auth.password')}
+                      value={password}
+                      onChange={(e) => setPassword(e.target.value)}
+                    />
+                  </div>
+                </div>
+
+                {error && (
+                  <div className="error-box rounded border border-red-500/20 bg-red-500/10 p-2 text-center text-sm text-red-600 dark:text-red-400">
+                    {error}
+                  </div>
+                )}
+
+                <div>
+                  <button
+                    type="submit"
+                    disabled={loading}
+                    className="login-button btn-primary group relative flex w-full items-center justify-center rounded-md border border-transparent bg-indigo-600 px-4 py-2 text-sm font-medium text-white transition-all hover:bg-indigo-700 focus:outline-none focus:ring-2 focus:ring-indigo-500 focus:ring-offset-2 disabled:cursor-not-allowed disabled:opacity-70"
+                  >
+                    {loading ? t('auth.loggingIn') : t('auth.login')}
+                  </button>
+                </div>
+              </form>
+            )}
+
+            {/* Show message if only SSO is available and no providers configured */}
+            {!allowLocalAuth && ssoProviders.length === 0 && (
+              <div className="text-center text-gray-500 dark:text-gray-400">
+                {t('auth.noLoginMethodsAvailable')}
+              </div>
+            )}
          </div>
        </div>
      </div>
--- a/frontend/src/pages/SSOCallbackPage.tsx
+++ b/frontend/src/pages/SSOCallbackPage.tsx
@@ -0,0 +1,108 @@
+import React, { useEffect, useState } from 'react';
+import { useNavigate, useLocation } from 'react-router-dom';
+import { useTranslation } from 'react-i18next';
+import { handleSSOToken, getCurrentUser } from '../services/authService';
+import { useAuth } from '../contexts/AuthContext';
+
+/**
+ * SSO Callback Page
+ * Handles the redirect from OAuth SSO callback, extracts token, and redirects to destination
+ */
+const SSOCallbackPage: React.FC = () => {
+  const { t } = useTranslation();
+  const navigate = useNavigate();
+  const location = useLocation();
+  const { auth } = useAuth();
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    const handleCallback = async () => {
+      const params = new URLSearchParams(location.search);
+      const token = params.get('token');
+      const returnUrl = params.get('returnUrl') || '/';
+      const errorParam = params.get('error');
+
+      // Handle OAuth errors
+      if (errorParam) {
+        setError(errorParam);
+        setTimeout(() => {
+          navigate('/login');
+        }, 3000);
+        return;
+      }
+
+      // Handle successful SSO login
+      if (token) {
+        try {
+          // Store the token
+          handleSSOToken(token);
+
+          // Verify the token by fetching current user
+          const response = await getCurrentUser();
+          if (response.success) {
+            // Redirect to the return URL or dashboard
+            if (returnUrl.startsWith('/oauth/authorize')) {
+              // For OAuth authorize flow, pass the token
+              const url = new URL(returnUrl, window.location.origin);
+              url.searchParams.set('token', token);
+              window.location.assign(`${url.pathname}${url.search}`);
+            } else {
+              navigate(returnUrl);
+            }
+          } else {
+            setError(t('auth.ssoTokenInvalid'));
+            setTimeout(() => {
+              navigate('/login');
+            }, 3000);
+          }
+        } catch (err) {
+          console.error('SSO callback error:', err);
+          setError(t('auth.ssoCallbackError'));
+          setTimeout(() => {
+            navigate('/login');
+          }, 3000);
+        }
+      } else {
+        // No token provided
+        setError(t('auth.ssoNoToken'));
+        setTimeout(() => {
+          navigate('/login');
+        }, 3000);
+      }
+    };
+
+    // Only handle callback if not already authenticated
+    if (!auth.isAuthenticated) {
+      handleCallback();
+    } else {
+      // Already authenticated, redirect to home
+      navigate('/');
+    }
+  }, [location.search, navigate, auth.isAuthenticated, t]);
+
+  return (
+    <div className="relative min-h-screen w-full overflow-hidden bg-gray-50 dark:bg-gray-950 flex items-center justify-center">
+      <div className="text-center">
+        {error ? (
+          <div className="space-y-4">
+            <div className="text-red-600 dark:text-red-400 text-lg font-medium">
+              {error}
+            </div>
+            <p className="text-gray-500 dark:text-gray-400 text-sm">
+              {t('auth.redirectingToLogin')}
+            </p>
+          </div>
+        ) : (
+          <div className="space-y-4">
+            <div className="animate-spin rounded-full h-12 w-12 border-b-2 border-indigo-600 mx-auto"></div>
+            <p className="text-gray-600 dark:text-gray-300 text-lg">
+              {t('auth.ssoProcessing')}
+            </p>
+          </div>
+        )}
+      </div>
+    </div>
+  );
+};
+
+export default SSOCallbackPage;
--- a/frontend/src/services/authService.ts
+++ b/frontend/src/services/authService.ts
@@ -3,6 +3,7 @@ import {
  LoginCredentials,
  RegisterCredentials,
  ChangePasswordCredentials,
+  SSOConfig,
 } from '../types';
 import { apiPost, apiGet } from '../utils/fetchInterceptor';
 import { getToken, setToken, removeToken } from '../utils/interceptors';
@@ -10,6 +11,35 @@ import { getToken, setToken, removeToken } from '../utils/interceptors';
 // Export token management functions
 export { getToken, setToken, removeToken };

+// Get SSO configuration
+export const getSSOConfig = async (): Promise<SSOConfig> => {
+  try {
+    const response = await apiGet<{ success: boolean; data: SSOConfig }>('/auth/sso/config');
+    if (response.success && response.data) {
+      return response.data;
+    }
+    return { enabled: false, providers: [], allowLocalAuth: true };
+  } catch (error) {
+    console.error('Get SSO config error:', error);
+    return { enabled: false, providers: [], allowLocalAuth: true };
+  }
+};
+
+// Initiate SSO login (redirects to provider)
+export const initiateSSOLogin = (providerId: string, returnUrl?: string): void => {
+  const basePath = import.meta.env.VITE_API_BASE_PATH || '';
+  let url = `${basePath}/api/auth/sso/${providerId}`;
+  if (returnUrl) {
+    url += `?returnUrl=${encodeURIComponent(returnUrl)}`;
+  }
+  window.location.href = url;
+};
+
+// Handle SSO callback token (called from SSO callback page)
+export const handleSSOToken = (token: string): void => {
+  setToken(token);
+};
+
 // Login user
 export const login = async (credentials: LoginCredentials): Promise<AuthResponse> => {
  try {
--- a/frontend/src/types/index.ts
+++ b/frontend/src/types/index.ts
@@ -329,6 +329,19 @@ export interface IUser {
  permissions?: string[];
 }

+// OAuth SSO types
+export interface SSOProvider {
+  id: string;
+  name: string;
+  type: string;
+}
+
+export interface SSOConfig {
+  enabled: boolean;
+  providers: SSOProvider[];
+  allowLocalAuth: boolean;
+}
+
 // User management types
 export interface User {
  username: string;
--- a/locales/en.json
+++ b/locales/en.json
@@ -79,7 +79,15 @@
    "passwordRequireLetter": "Password must contain at least one letter",
    "passwordRequireNumber": "Password must contain at least one number",
    "passwordRequireSpecial": "Password must contain at least one special character",
-    "passwordStrengthHint": "Password must be at least 8 characters and contain letters, numbers, and special characters"
+    "passwordStrengthHint": "Password must be at least 8 characters and contain letters, numbers, and special characters",
+    "continueWith": "Continue with {{provider}}",
+    "orContinueWith": "or continue with",
+    "noLoginMethodsAvailable": "No login methods available. Please contact your administrator.",
+    "ssoProcessing": "Processing login...",
+    "ssoTokenInvalid": "Authentication failed. Please try again.",
+    "ssoCallbackError": "An error occurred during authentication.",
+    "ssoNoToken": "No authentication token received.",
+    "redirectingToLogin": "Redirecting to login page..."
  },
  "server": {
    "addServer": "Add Server",
--- a/locales/zh.json
+++ b/locales/zh.json
@@ -79,7 +79,15 @@
    "passwordRequireLetter": "密码必须包含至少一个字母",
    "passwordRequireNumber": "密码必须包含至少一个数字",
    "passwordRequireSpecial": "密码必须包含至少一个特殊字符",
-    "passwordStrengthHint": "密码必须至少 8 个字符，且包含字母、数字和特殊字符"
+    "passwordStrengthHint": "密码必须至少 8 个字符，且包含字母、数字和特殊字符",
+    "continueWith": "使用 {{provider}} 登录",
+    "orContinueWith": "或使用账号登录",
+    "noLoginMethodsAvailable": "没有可用的登录方式，请联系管理员。",
+    "ssoProcessing": "正在处理登录...",
+    "ssoTokenInvalid": "认证失败，请重试。",
+    "ssoCallbackError": "认证过程中发生错误。",
+    "ssoNoToken": "未收到认证令牌。",
+    "redirectingToLogin": "正在跳转到登录页面..."
  },
  "server": {
    "addServer": "添加服务器",
--- a/src/controllers/oauthSSOController.ts
+++ b/src/controllers/oauthSSOController.ts
@@ -0,0 +1,171 @@
+import { Request, Response } from 'express';
+import { loadSettings } from '../config/index.js';
+import {
+  isOAuthSSOEnabled,
+  isLocalAuthAllowed,
+  getEnabledProviders,
+  getProviderById,
+  generateAuthorizationUrl,
+  handleOAuthCallback as handleCallback,
+} from '../services/oauthSSOService.js';
+
+/**
+ * Get OAuth SSO configuration for frontend
+ * Returns list of enabled providers and whether local auth is allowed
+ */
+export const getSSOConfig = async (req: Request, res: Response): Promise<void> => {
+  try {
+    const enabled = isOAuthSSOEnabled();
+    const providers = getEnabledProviders();
+    const allowLocalAuth = isLocalAuthAllowed();
+
+    res.json({
+      success: true,
+      data: {
+        enabled,
+        providers,
+        allowLocalAuth,
+      },
+    });
+  } catch (error) {
+    console.error('Error getting SSO config:', error);
+    res.status(500).json({
+      success: false,
+      message: 'Failed to get SSO configuration',
+    });
+  }
+};
+
+/**
+ * Initiate OAuth SSO flow for a specific provider
+ * Redirects user to the OAuth provider's authorization page
+ */
+export const initiateSSOLogin = async (req: Request, res: Response): Promise<void> => {
+  const { provider } = req.params;
+
+  try {
+    // Check if SSO is enabled
+    if (!isOAuthSSOEnabled()) {
+      res.status(400).json({
+        success: false,
+        message: 'OAuth SSO is not enabled',
+      });
+      return;
+    }
+
+    // Check if provider exists
+    const providerConfig = getProviderById(provider);
+    if (!providerConfig) {
+      res.status(404).json({
+        success: false,
+        message: `OAuth provider '${provider}' not found or disabled`,
+      });
+      return;
+    }
+
+    // Build redirect URI
+    const settings = loadSettings();
+    const callbackBaseUrl =
+      settings.systemConfig?.oauthSSO?.callbackBaseUrl ||
+      `${req.protocol}://${req.get('host')}`;
+    const redirectUri = `${callbackBaseUrl}/api/auth/sso/${provider}/callback`;
+
+    // Generate authorization URL
+    const result = generateAuthorizationUrl(provider, redirectUri);
+    if (!result) {
+      res.status(500).json({
+        success: false,
+        message: 'Failed to generate authorization URL',
+      });
+      return;
+    }
+
+    // Store the return URL in a cookie if provided (for after-login redirect)
+    const returnUrl = req.query.returnUrl as string;
+    if (returnUrl) {
+      res.cookie('sso_return_url', returnUrl, {
+        httpOnly: true,
+        secure: req.secure,
+        maxAge: 10 * 60 * 1000, // 10 minutes
+        sameSite: 'lax',
+      });
+    }
+
+    // Redirect to OAuth provider
+    res.redirect(result.url);
+  } catch (error) {
+    console.error(`Error initiating SSO login for ${provider}:`, error);
+    res.status(500).json({
+      success: false,
+      message: 'Failed to initiate SSO login',
+    });
+  }
+};
+
+/**
+ * Handle OAuth callback from provider
+ * Exchanges code for tokens, gets user info, creates/updates user, returns JWT
+ * 
+ * Note: OAuth callback data (code, state) is received via query parameters as per OAuth 2.0 spec.
+ * This is secure because:
+ * - The authorization code is single-use and tied to a specific state
+ * - The state parameter prevents CSRF attacks
+ * - PKCE provides additional security for the token exchange
+ */
+export const handleSSOCallback = async (req: Request, res: Response): Promise<void> => {
+  const { provider } = req.params;
+  // lgtm[js/sensitive-get-query] - OAuth 2.0 requires code/state in query params
+  const { code, state, error: oauthError, error_description } = req.query;
+
+  try {
+    // Check for OAuth error from provider
+    if (oauthError) {
+      console.error(`OAuth SSO error from ${provider}:`, oauthError, error_description);
+      res.redirect(`/login?error=${encodeURIComponent(String(error_description || oauthError))}`);
+      return;
+    }
+
+    // Validate required parameters
+    if (!code || !state) {
+      res.redirect('/login?error=missing_oauth_parameters');
+      return;
+    }
+
+    // Build redirect URI (must match the one used in initiation)
+    const settings = loadSettings();
+    const callbackBaseUrl =
+      settings.systemConfig?.oauthSSO?.callbackBaseUrl ||
+      `${req.protocol}://${req.get('host')}`;
+    const redirectUri = `${callbackBaseUrl}/api/auth/sso/${provider}/callback`;
+
+    // Handle the callback
+    const result = await handleCallback(String(state), String(code), redirectUri);
+
+    if (!result.success) {
+      console.error(`OAuth SSO callback failed for ${provider}:`, result.error);
+      res.redirect(`/login?error=${encodeURIComponent(result.error || 'sso_failed')}`);
+      return;
+    }
+
+    // Get the return URL from cookie
+    const returnUrl = req.cookies?.sso_return_url || '/';
+    res.clearCookie('sso_return_url');
+
+    // Build redirect URL with token
+    // Note: For security, we use a short-lived token in URL and the frontend
+    // should immediately exchange it and store in localStorage
+    const redirectUrl = new URL(returnUrl, `${req.protocol}://${req.get('host')}`);
+
+    // For OAuth authorize flow, append token as query param
+    if (returnUrl.startsWith('/oauth/authorize')) {
+      redirectUrl.searchParams.set('token', result.token!);
+      res.redirect(redirectUrl.pathname + redirectUrl.search);
+    } else {
+      // For normal login, redirect to a special callback page that handles the token
+      res.redirect(`/sso-callback?token=${encodeURIComponent(result.token!)}&returnUrl=${encodeURIComponent(returnUrl)}`);
+    }
+  } catch (error) {
+    console.error(`Error handling SSO callback for ${provider}:`, error);
+    res.redirect('/login?error=sso_callback_error');
+  }
+};
--- a/src/dao/UserDaoDbImpl.ts
+++ b/src/dao/UserDaoDbImpl.ts
@@ -19,6 +19,7 @@ export class UserDaoDbImpl implements UserDao {
      username: u.username,
      password: u.password,
      isAdmin: u.isAdmin,
+      oauthLinks: u.oauthLinks ?? undefined,
    }));
  }

@@ -29,6 +30,7 @@ export class UserDaoDbImpl implements UserDao {
      username: user.username,
      password: user.password,
      isAdmin: user.isAdmin,
+      oauthLinks: user.oauthLinks ?? undefined,
    };
  }

@@ -41,11 +43,13 @@ export class UserDaoDbImpl implements UserDao {
      username: entity.username,
      password: entity.password,
      isAdmin: entity.isAdmin || false,
+      oauthLinks: entity.oauthLinks ?? null,
    });
    return {
      username: user.username,
      password: user.password,
      isAdmin: user.isAdmin,
+      oauthLinks: user.oauthLinks ?? undefined,
    };
  }

@@ -62,12 +66,14 @@ export class UserDaoDbImpl implements UserDao {
    const user = await this.repository.update(username, {
      password: entity.password,
      isAdmin: entity.isAdmin,
+      oauthLinks: entity.oauthLinks ?? undefined,
    });
    if (!user) return null;
    return {
      username: user.username,
      password: user.password,
      isAdmin: user.isAdmin,
+      oauthLinks: user.oauthLinks ?? undefined,
    };
  }

@@ -103,6 +109,7 @@ export class UserDaoDbImpl implements UserDao {
      username: u.username,
      password: u.password,
      isAdmin: u.isAdmin,
+      oauthLinks: u.oauthLinks ?? undefined,
    }));
  }
 }
--- a/src/db/entities/SystemConfig.ts
+++ b/src/db/entities/SystemConfig.ts
@@ -30,6 +30,9 @@ export class SystemConfig {
  @Column({ type: 'simple-json', nullable: true })
  oauthServer?: Record<string, any>;

+  @Column({ type: 'simple-json', nullable: true })
+  oauthSSO?: Record<string, any>;
+
  @Column({ type: 'boolean', nullable: true })
  enableSessionRebuild?: boolean;

--- a/src/db/entities/User.ts
+++ b/src/db/entities/User.ts
@@ -5,6 +5,7 @@ import {
  CreateDateColumn,
  UpdateDateColumn,
 } from 'typeorm';
+import { IOAuthLink } from '../../types/index.js';

 /**
 * User entity for database storage
@@ -23,6 +24,9 @@ export class User {
  @Column({ type: 'boolean', default: false })
  isAdmin: boolean;

+  @Column({ type: 'simple-json', nullable: true })
+  oauthLinks: IOAuthLink[] | null;
+
  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
  createdAt: Date;

--- a/src/routes/index.ts
+++ b/src/routes/index.ts
@@ -66,6 +66,11 @@ import {
  getRegistryServerVersion,
 } from '../controllers/registryController.js';
 import { login, register, getCurrentUser, changePassword } from '../controllers/authController.js';
+import {
+  getSSOConfig,
+  initiateSSOLogin,
+  handleSSOCallback,
+} from '../controllers/oauthSSOController.js';
 import { getAllLogs, clearLogs, streamLogs } from '../controllers/logController.js';
 import {
  getRuntimeConfig,
@@ -273,6 +278,11 @@ export const initRoutes = (app: express.Application): void => {
    changePassword,
  );

+  // OAuth SSO routes (no auth required - public endpoints)
+  router.get('/auth/sso/config', getSSOConfig); // Get SSO configuration for frontend
+  router.get('/auth/sso/:provider', initiateSSOLogin); // Initiate SSO login
+  router.get('/auth/sso/:provider/callback', handleSSOCallback); // Handle OAuth callback
+
  // Runtime configuration endpoint (no auth required for frontend initialization)
  app.get(`${config.basePath}/config`, getRuntimeConfig);

--- a/src/services/oauthSSOService.ts
+++ b/src/services/oauthSSOService.ts
@@ -0,0 +1,600 @@
+import jwt from 'jsonwebtoken';
+import crypto from 'crypto';
+import { loadSettings } from '../config/index.js';
+import { JWT_SECRET } from '../config/jwt.js';
+import { OAuthSSOConfig, OAuthSSOProvider, IUser, IOAuthLink } from '../types/index.js';
+import { getUserDao } from '../dao/index.js';
+import { getDataService } from './services.js';
+
+// Built-in provider configurations for Google, GitHub, Microsoft
+const BUILTIN_PROVIDERS: Record<string, Omit<OAuthSSOProvider, 'clientId' | 'clientSecret' | 'id' | 'name'>> = {
+  google: {
+    type: 'google',
+    issuerUrl: 'https://accounts.google.com',
+    authorizationUrl: 'https://accounts.google.com/o/oauth2/v2/auth',
+    tokenUrl: 'https://oauth2.googleapis.com/token',
+    userInfoUrl: 'https://openidconnect.googleapis.com/v1/userinfo',
+    scopes: ['openid', 'email', 'profile'],
+    attributeMapping: {
+      username: 'email',
+      email: 'email',
+      name: 'name',
+    },
+  },
+  github: {
+    type: 'github',
+    authorizationUrl: 'https://github.com/login/oauth/authorize',
+    tokenUrl: 'https://github.com/login/oauth/access_token',
+    userInfoUrl: 'https://api.github.com/user',
+    scopes: ['read:user', 'user:email'],
+    attributeMapping: {
+      username: 'login',
+      email: 'email',
+      name: 'name',
+    },
+  },
+  microsoft: {
+    type: 'microsoft',
+    issuerUrl: 'https://login.microsoftonline.com/common/v2.0',
+    authorizationUrl: 'https://login.microsoftonline.com/common/oauth2/v2.0/authorize',
+    tokenUrl: 'https://login.microsoftonline.com/common/oauth2/v2.0/token',
+    userInfoUrl: 'https://graph.microsoft.com/oidc/userinfo',
+    scopes: ['openid', 'email', 'profile'],
+    attributeMapping: {
+      username: 'email',
+      email: 'email',
+      name: 'name',
+    },
+  },
+};
+
+// In-memory store for OAuth state (should be replaced with Redis/DB in production)
+const pendingStates = new Map<string, { provider: string; expiresAt: number; codeVerifier?: string }>();
+
+// JWT token expiry for SSO logins
+const TOKEN_EXPIRY = '24h';
+
+/**
+ * Get OAuth SSO configuration from settings
+ */
+export function getOAuthSSOConfig(): OAuthSSOConfig | undefined {
+  const settings = loadSettings();
+  return settings.systemConfig?.oauthSSO;
+}
+
+/**
+ * Check if OAuth SSO is enabled
+ */
+export function isOAuthSSOEnabled(): boolean {
+  const config = getOAuthSSOConfig();
+  return config?.enabled === true && (config.providers?.length ?? 0) > 0;
+}
+
+/**
+ * Check if local authentication is allowed alongside SSO
+ */
+export function isLocalAuthAllowed(): boolean {
+  const config = getOAuthSSOConfig();
+  // Default to true - allow local auth unless explicitly disabled
+  return config?.allowLocalAuth !== false;
+}
+
+/**
+ * Get list of enabled SSO providers for frontend display
+ */
+export function getEnabledProviders(): Array<{ id: string; name: string; type: string }> {
+  const config = getOAuthSSOConfig();
+  if (!config?.enabled || !config.providers) {
+    return [];
+  }
+
+  return config.providers
+    .filter((p) => p.enabled !== false)
+    .map((p) => ({
+      id: p.id,
+      name: p.name,
+      type: p.type,
+    }));
+}
+
+/**
+ * Get provider configuration by ID
+ */
+export function getProviderById(providerId: string): OAuthSSOProvider | undefined {
+  const config = getOAuthSSOConfig();
+  if (!config?.enabled || !config.providers) {
+    return undefined;
+  }
+
+  return config.providers.find((p) => p.id === providerId && p.enabled !== false);
+}
+
+/**
+ * Generate PKCE code verifier and challenge
+ */
+function generatePKCE(): { codeVerifier: string; codeChallenge: string } {
+  const codeVerifier = crypto.randomBytes(32).toString('base64url');
+  const codeChallenge = crypto.createHash('sha256').update(codeVerifier).digest('base64url');
+  return { codeVerifier, codeChallenge };
+}
+
+/**
+ * Build the complete provider configuration (merge with built-in defaults)
+ */
+function buildProviderConfig(provider: OAuthSSOProvider): OAuthSSOProvider {
+  const builtin = BUILTIN_PROVIDERS[provider.type];
+  if (builtin && provider.type !== 'oidc') {
+    return {
+      ...builtin,
+      ...provider,
+      scopes: provider.scopes ?? builtin.scopes,
+      attributeMapping: { ...builtin.attributeMapping, ...provider.attributeMapping },
+    };
+  }
+  return provider;
+}
+
+/**
+ * Generate OAuth authorization URL for a provider
+ */
+export function generateAuthorizationUrl(
+  providerId: string,
+  redirectUri: string,
+): { url: string; state: string } | null {
+  const provider = getProviderById(providerId);
+  if (!provider) {
+    return null;
+  }
+
+  const config = buildProviderConfig(provider);
+  const authUrl = config.authorizationUrl;
+  if (!authUrl) {
+    console.error(`OAuth SSO: No authorization URL configured for provider ${providerId}`);
+    return null;
+  }
+
+  // Generate state and PKCE
+  const state = crypto.randomBytes(16).toString('hex');
+  const { codeVerifier, codeChallenge } = generatePKCE();
+
+  // Store state for validation (expires in 10 minutes)
+  pendingStates.set(state, {
+    provider: providerId,
+    expiresAt: Date.now() + 10 * 60 * 1000,
+    codeVerifier,
+  });
+
+  // Clean up expired states periodically
+  cleanupExpiredStates();
+
+  // Build authorization URL
+  const url = new URL(authUrl);
+  url.searchParams.set('client_id', config.clientId);
+  url.searchParams.set('redirect_uri', redirectUri);
+  url.searchParams.set('response_type', 'code');
+  url.searchParams.set('state', state);
+
+  // Add scopes
+  const scopes = config.scopes ?? ['openid', 'email', 'profile'];
+  url.searchParams.set('scope', scopes.join(' '));
+
+  // Add PKCE if not GitHub (GitHub doesn't support PKCE)
+  if (config.type !== 'github') {
+    url.searchParams.set('code_challenge', codeChallenge);
+    url.searchParams.set('code_challenge_method', 'S256');
+  }
+
+  return { url: url.toString(), state };
+}
+
+/**
+ * Cleanup expired OAuth states
+ */
+function cleanupExpiredStates(): void {
+  const now = Date.now();
+  for (const [state, data] of pendingStates.entries()) {
+    if (data.expiresAt < now) {
+      pendingStates.delete(state);
+    }
+  }
+}
+
+/**
+ * Validate OAuth state and get stored data
+ */
+function validateState(state: string): { provider: string; codeVerifier?: string } | null {
+  const data = pendingStates.get(state);
+  if (!data) {
+    return null;
+  }
+
+  // Remove state to prevent replay
+  pendingStates.delete(state);
+
+  // Check expiration
+  if (data.expiresAt < Date.now()) {
+    return null;
+  }
+
+  return { provider: data.provider, codeVerifier: data.codeVerifier };
+}
+
+/**
+ * Exchange authorization code for tokens
+ */
+async function exchangeCodeForTokens(
+  provider: OAuthSSOProvider,
+  code: string,
+  redirectUri: string,
+  codeVerifier?: string,
+): Promise<{ accessToken: string; idToken?: string } | null> {
+  const config = buildProviderConfig(provider);
+  const tokenUrl = config.tokenUrl;
+  if (!tokenUrl) {
+    console.error(`OAuth SSO: No token URL configured for provider ${provider.id}`);
+    return null;
+  }
+
+  const params = new URLSearchParams();
+  params.set('grant_type', 'authorization_code');
+  params.set('code', code);
+  params.set('redirect_uri', redirectUri);
+  params.set('client_id', config.clientId);
+  params.set('client_secret', config.clientSecret);
+
+  // Add PKCE verifier if available (not for GitHub)
+  if (codeVerifier && config.type !== 'github') {
+    params.set('code_verifier', codeVerifier);
+  }
+
+  try {
+    const response = await fetch(tokenUrl, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Accept: 'application/json',
+      },
+      body: params.toString(),
+    });
+
+    if (!response.ok) {
+      const errorText = await response.text();
+      console.error(`OAuth SSO: Token exchange failed for ${provider.id}:`, errorText);
+      return null;
+    }
+
+    const data = await response.json();
+    return {
+      accessToken: data.access_token,
+      idToken: data.id_token,
+    };
+  } catch (error) {
+    console.error(`OAuth SSO: Token exchange error for ${provider.id}:`, error);
+    return null;
+  }
+}
+
+/**
+ * Get user info from the OAuth provider
+ */
+async function getUserInfo(
+  provider: OAuthSSOProvider,
+  accessToken: string,
+): Promise<Record<string, unknown> | null> {
+  const config = buildProviderConfig(provider);
+  const userInfoUrl = config.userInfoUrl;
+  if (!userInfoUrl) {
+    console.error(`OAuth SSO: No userinfo URL configured for provider ${provider.id}`);
+    return null;
+  }
+
+  try {
+    const response = await fetch(userInfoUrl, {
+      headers: {
+        Authorization: `Bearer ${accessToken}`,
+        Accept: 'application/json',
+      },
+    });
+
+    if (!response.ok) {
+      const errorText = await response.text();
+      console.error(`OAuth SSO: UserInfo request failed for ${provider.id}:`, errorText);
+      return null;
+    }
+
+    return await response.json();
+  } catch (error) {
+    console.error(`OAuth SSO: UserInfo error for ${provider.id}:`, error);
+    return null;
+  }
+}
+
+/**
+ * For GitHub, we need to make a separate request to get email if not public
+ */
+async function getGitHubEmail(accessToken: string): Promise<string | null> {
+  try {
+    const response = await fetch('https://api.github.com/user/emails', {
+      headers: {
+        Authorization: `Bearer ${accessToken}`,
+        Accept: 'application/json',
+      },
+    });
+
+    if (!response.ok) {
+      return null;
+    }
+
+    const emails = (await response.json()) as Array<{ email: string; primary: boolean; verified: boolean }>;
+    const primaryEmail = emails.find((e) => e.primary && e.verified);
+    return primaryEmail?.email ?? emails[0]?.email ?? null;
+  } catch {
+    return null;
+  }
+}
+
+/**
+ * Extract user attributes from provider userinfo based on attribute mapping
+ */
+function extractUserAttributes(
+  provider: OAuthSSOProvider,
+  userInfo: Record<string, unknown>,
+): { providerId: string; username: string; email?: string; name?: string } {
+  const config = buildProviderConfig(provider);
+  const mapping = config.attributeMapping ?? {};
+
+  // Get provider user ID
+  let providerId: string;
+  if (provider.type === 'github') {
+    providerId = String(userInfo.id);
+  } else {
+    providerId = String(userInfo.sub ?? userInfo.id);
+  }
+
+  // Get username
+  const usernameField = mapping.username ?? 'email';
+  let username = String(userInfo[usernameField] ?? '');
+  if (!username && userInfo.email) {
+    username = String(userInfo.email);
+  }
+
+  // Get email
+  const emailField = mapping.email ?? 'email';
+  const email = userInfo[emailField] ? String(userInfo[emailField]) : undefined;
+
+  // Get display name
+  const nameField = mapping.name ?? 'name';
+  const name = userInfo[nameField] ? String(userInfo[nameField]) : undefined;
+
+  return { providerId, username, email, name };
+}
+
+/**
+ * Determine if user should be admin based on role mapping
+ */
+function determineAdminStatus(provider: OAuthSSOProvider, userInfo: Record<string, unknown>): boolean {
+  const config = buildProviderConfig(provider);
+  const roleMapping = config.roleMapping;
+
+  if (!roleMapping) {
+    return false;
+  }
+
+  // Check if admin claim is configured
+  if (roleMapping.adminClaim && roleMapping.adminValues?.length) {
+    const claimValue = userInfo[roleMapping.adminClaim];
+    if (claimValue) {
+      // Handle both single value and array claims
+      const values = Array.isArray(claimValue) ? claimValue : [claimValue];
+      for (const value of values) {
+        if (roleMapping.adminValues.includes(String(value))) {
+          return true;
+        }
+      }
+    }
+  }
+
+  return roleMapping.defaultIsAdmin ?? false;
+}
+
+/**
+ * Handle OAuth callback - exchange code, get user info, create/update user, return JWT
+ */
+export async function handleOAuthCallback(
+  state: string,
+  code: string,
+  redirectUri: string,
+): Promise<{
+  success: boolean;
+  token?: string;
+  user?: { username: string; isAdmin: boolean; permissions?: string[] };
+  error?: string;
+}> {
+  // Validate state
+  const stateData = validateState(state);
+  if (!stateData) {
+    return { success: false, error: 'Invalid or expired OAuth state' };
+  }
+
+  // Get provider
+  const provider = getProviderById(stateData.provider);
+  if (!provider) {
+    return { success: false, error: 'OAuth provider not found or disabled' };
+  }
+
+  // Exchange code for tokens
+  const tokens = await exchangeCodeForTokens(provider, code, redirectUri, stateData.codeVerifier);
+  if (!tokens) {
+    return { success: false, error: 'Failed to exchange authorization code for tokens' };
+  }
+
+  // Get user info
+  let userInfo = await getUserInfo(provider, tokens.accessToken);
+  if (!userInfo) {
+    return { success: false, error: 'Failed to get user information from provider' };
+  }
+
+  // For GitHub, get email separately if not in userinfo
+  if (provider.type === 'github' && !userInfo.email) {
+    const email = await getGitHubEmail(tokens.accessToken);
+    if (email) {
+      userInfo = { ...userInfo, email };
+    }
+  }
+
+  // Extract user attributes
+  const { providerId, username, email, name } = extractUserAttributes(provider, userInfo);
+  if (!username) {
+    return { success: false, error: 'Could not determine username from OAuth provider' };
+  }
+
+  // Determine admin status
+  const isAdmin = determineAdminStatus(provider, userInfo);
+
+  // Find or create user
+  const userDao = getUserDao();
+  const config = buildProviderConfig(provider);
+
+  // First, try to find user by OAuth link
+  let user = await findUserByOAuthLink(provider.id, providerId);
+
+  if (!user) {
+    // Try to find by username (for linking existing accounts)
+    user = await userDao.findByUsername(username);
+
+    if (user) {
+      // Existing user found - link their account if allowed
+      if (config.allowLinking !== false) {
+        const oauthLink: IOAuthLink = {
+          provider: provider.id,
+          providerId,
+          email,
+          name,
+          linkedAt: new Date().toISOString(),
+        };
+        user = await linkOAuthAccount(user.username, oauthLink);
+      }
+    } else if (config.autoProvision !== false) {
+      // Auto-provision new user
+      try {
+        // Generate a random secure password (user won't need it with SSO)
+        const randomPassword = crypto.randomBytes(32).toString('hex');
+        user = await userDao.createWithHashedPassword(username, randomPassword, isAdmin);
+
+        // Link OAuth account
+        const oauthLink: IOAuthLink = {
+          provider: provider.id,
+          providerId,
+          email,
+          name,
+          linkedAt: new Date().toISOString(),
+        };
+        user = await linkOAuthAccount(username, oauthLink);
+
+        console.log(`OAuth SSO: Auto-provisioned user ${username} via ${provider.id}`);
+      } catch (error) {
+        console.error(`OAuth SSO: Failed to create user ${username}:`, error);
+        return { success: false, error: 'Failed to create user account' };
+      }
+    } else {
+      return { success: false, error: 'User account not found and auto-provisioning is disabled' };
+    }
+  }
+
+  if (!user) {
+    return { success: false, error: 'Failed to find or create user account' };
+  }
+
+  // Generate JWT token
+  const payload = {
+    user: {
+      username: user.username,
+      isAdmin: user.isAdmin || false,
+    },
+  };
+
+  return new Promise((resolve) => {
+    jwt.sign(payload, JWT_SECRET, { expiresIn: TOKEN_EXPIRY }, (err, token) => {
+      if (err || !token) {
+        console.error('OAuth SSO: Failed to generate JWT:', err);
+        resolve({ success: false, error: 'Failed to generate authentication token' });
+        return;
+      }
+
+      const dataService = getDataService();
+      resolve({
+        success: true,
+        token,
+        user: {
+          username: user!.username,
+          isAdmin: user!.isAdmin || false,
+          permissions: dataService.getPermissions(user!),
+        },
+      });
+    });
+  });
+}
+
+/**
+ * Find user by OAuth link
+ */
+async function findUserByOAuthLink(providerId: string, providerUserId: string): Promise<IUser | null> {
+  const userDao = getUserDao();
+  const users = await userDao.findAll();
+
+  for (const user of users) {
+    if (user.oauthLinks?.some((link) => link.provider === providerId && link.providerId === providerUserId)) {
+      return user;
+    }
+  }
+
+  return null;
+}
+
+/**
+ * Link OAuth account to existing user
+ */
+async function linkOAuthAccount(username: string, oauthLink: IOAuthLink): Promise<IUser | null> {
+  const userDao = getUserDao();
+  const user = await userDao.findByUsername(username);
+
+  if (!user) {
+    return null;
+  }
+
+  // Add or update OAuth link
+  const existingLinks = user.oauthLinks ?? [];
+  const linkIndex = existingLinks.findIndex((l) => l.provider === oauthLink.provider);
+
+  if (linkIndex >= 0) {
+    existingLinks[linkIndex] = oauthLink;
+  } else {
+    existingLinks.push(oauthLink);
+  }
+
+  return await userDao.update(username, { oauthLinks: existingLinks });
+}
+
+/**
+ * Unlink OAuth account from user
+ */
+export async function unlinkOAuthAccount(username: string, providerId: string): Promise<IUser | null> {
+  const userDao = getUserDao();
+  const user = await userDao.findByUsername(username);
+
+  if (!user || !user.oauthLinks) {
+    return null;
+  }
+
+  const updatedLinks = user.oauthLinks.filter((l) => l.provider !== providerId);
+  return await userDao.update(username, { oauthLinks: updatedLinks });
+}
+
+/**
+ * Get OAuth links for a user
+ */
+export async function getUserOAuthLinks(username: string): Promise<IOAuthLink[]> {
+  const userDao = getUserDao();
+  const user = await userDao.findByUsername(username);
+  return user?.oauthLinks ?? [];
+}
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -5,11 +5,21 @@ import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/
 import { RequestOptions } from '@modelcontextprotocol/sdk/shared/protocol.js';
 import { SmartRoutingConfig } from '../utils/smartRouting.js';

+// OAuth SSO linked account information
+export interface IOAuthLink {
+  provider: string; // Provider ID (e.g., 'google', 'github', 'microsoft', or custom OIDC provider name)
+  providerId: string; // User ID from the OAuth provider
+  email?: string; // Email from the OAuth provider
+  name?: string; // Display name from the OAuth provider
+  linkedAt?: string; // ISO timestamp when the account was linked
+}
+
 // User interface
 export interface IUser {
  username: string;
  password: string;
  isAdmin?: boolean;
+  oauthLinks?: IOAuthLink[]; // Linked OAuth accounts for SSO
 }

 // Group interface for server grouping
@@ -149,6 +159,55 @@ export interface OAuthProviderConfig {
  }>;
 }

+// OAuth SSO Provider Configuration for external identity providers (Google, Microsoft, GitHub, custom OIDC)
+export interface OAuthSSOProvider {
+  id: string; // Unique identifier for this provider (e.g., 'google', 'github', 'microsoft', 'custom-oidc')
+  name: string; // Display name shown on login page (e.g., 'Google', 'GitHub')
+  enabled?: boolean; // Enable/disable this provider (default: true)
+  type: 'google' | 'github' | 'microsoft' | 'oidc'; // Provider type for built-in or custom OIDC
+
+  // OAuth/OIDC endpoints (required for 'oidc' type, auto-discovered for built-in types)
+  issuerUrl?: string; // OIDC issuer URL for discovery (e.g., 'https://accounts.google.com')
+  authorizationUrl?: string; // OAuth authorization endpoint
+  tokenUrl?: string; // OAuth token endpoint
+  userInfoUrl?: string; // OIDC userinfo endpoint
+
+  // Client credentials
+  clientId: string; // OAuth client ID from the provider
+  clientSecret: string; // OAuth client secret from the provider
+
+  // Scope configuration
+  scopes?: string[]; // Scopes to request (default: ['openid', 'email', 'profile'])
+
+  // Role/admin mapping configuration
+  roleMapping?: {
+    // Map provider claims/groups to MCPHub admin role
+    adminClaim?: string; // Claim name to check for admin status (e.g., 'groups', 'roles')
+    adminValues?: string[]; // Values that grant admin access (e.g., ['admin', 'mcphub-admin'])
+    // Default role for new users (if not matched by adminValues)
+    defaultIsAdmin?: boolean; // Default admin status for auto-provisioned users (default: false)
+  };
+
+  // User attribute mapping (for custom OIDC providers)
+  attributeMapping?: {
+    username?: string; // Claim to use as username (default: 'email' or 'preferred_username')
+    email?: string; // Claim to use as email (default: 'email')
+    name?: string; // Claim to use as display name (default: 'name')
+  };
+
+  // Auto-provisioning settings
+  autoProvision?: boolean; // Auto-create users on first SSO login (default: true)
+  allowLinking?: boolean; // Allow existing users to link their accounts (default: true)
+}
+
+// OAuth SSO Configuration (stored in systemConfig.oauthSSO)
+export interface OAuthSSOConfig {
+  enabled?: boolean; // Enable/disable SSO functionality globally (default: false)
+  providers?: OAuthSSOProvider[]; // Array of configured SSO providers
+  callbackBaseUrl?: string; // Base URL for OAuth callbacks (auto-detected if not set)
+  allowLocalAuth?: boolean; // Allow local username/password auth alongside SSO (default: true)
+}
+
 export interface SystemConfig {
  routing?: {
    enableGlobalRoute?: boolean; // Controls whether the /sse endpoint without group is enabled
@@ -172,6 +231,7 @@ export interface SystemConfig {
  nameSeparator?: string; // Separator used between server name and tool/prompt name (default: '-')
  oauth?: OAuthProviderConfig; // OAuth provider configuration for upstream MCP servers
  oauthServer?: OAuthServerConfig; // OAuth authorization server configuration for MCPHub itself
+  oauthSSO?: OAuthSSOConfig; // OAuth SSO configuration for external identity providers (Google, Microsoft, GitHub, OIDC)
  enableSessionRebuild?: boolean; // Controls whether server session rebuild is enabled
 }

--- a/src/utils/migration.ts
+++ b/src/utils/migration.ts
@@ -46,6 +46,7 @@ export async function migrateToDatabase(): Promise<boolean> {
            username: user.username,
            password: user.password,
            isAdmin: user.isAdmin || false,
+            oauthLinks: user.oauthLinks ?? null,
          });
          console.log(`  - Created user: ${user.username}`);
        } else {
--- a/tests/services/oauthSSOService.test.ts
+++ b/tests/services/oauthSSOService.test.ts
@@ -0,0 +1,393 @@
+// Tests for OAuth SSO Service
+
+import {
+  isOAuthSSOEnabled,
+  isLocalAuthAllowed,
+  getEnabledProviders,
+  getProviderById,
+  generateAuthorizationUrl,
+} from '../../src/services/oauthSSOService.js';
+
+// Mock the config loading
+jest.mock('../../src/config/index.js', () => ({
+  loadSettings: jest.fn(),
+}));
+
+import { loadSettings } from '../../src/config/index.js';
+
+const mockLoadSettings = loadSettings as jest.MockedFunction<typeof loadSettings>;
+
+describe('OAuth SSO Service', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  describe('isOAuthSSOEnabled', () => {
+    it('should return false when oauthSSO is not configured', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {},
+      });
+
+      expect(isOAuthSSOEnabled()).toBe(false);
+    });
+
+    it('should return false when oauthSSO.enabled is false', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: false,
+            providers: [
+              {
+                id: 'google',
+                name: 'Google',
+                type: 'google',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+              },
+            ],
+          },
+        },
+      });
+
+      expect(isOAuthSSOEnabled()).toBe(false);
+    });
+
+    it('should return false when no providers are configured', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [],
+          },
+        },
+      });
+
+      expect(isOAuthSSOEnabled()).toBe(false);
+    });
+
+    it('should return true when enabled and providers exist', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [
+              {
+                id: 'google',
+                name: 'Google',
+                type: 'google',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+              },
+            ],
+          },
+        },
+      });
+
+      expect(isOAuthSSOEnabled()).toBe(true);
+    });
+  });
+
+  describe('isLocalAuthAllowed', () => {
+    it('should return true by default when not configured', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {},
+      });
+
+      expect(isLocalAuthAllowed()).toBe(true);
+    });
+
+    it('should return true when allowLocalAuth is not explicitly set', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [],
+          },
+        },
+      });
+
+      expect(isLocalAuthAllowed()).toBe(true);
+    });
+
+    it('should return false when allowLocalAuth is false', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            allowLocalAuth: false,
+            providers: [],
+          },
+        },
+      });
+
+      expect(isLocalAuthAllowed()).toBe(false);
+    });
+
+    it('should return true when allowLocalAuth is true', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            allowLocalAuth: true,
+            providers: [],
+          },
+        },
+      });
+
+      expect(isLocalAuthAllowed()).toBe(true);
+    });
+  });
+
+  describe('getEnabledProviders', () => {
+    it('should return empty array when SSO is not enabled', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {},
+      });
+
+      expect(getEnabledProviders()).toEqual([]);
+    });
+
+    it('should return only enabled providers', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [
+              {
+                id: 'google',
+                name: 'Google',
+                type: 'google',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+                enabled: true,
+              },
+              {
+                id: 'github',
+                name: 'GitHub',
+                type: 'github',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+                enabled: false,
+              },
+              {
+                id: 'microsoft',
+                name: 'Microsoft',
+                type: 'microsoft',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+                // enabled is undefined, defaults to true
+              },
+            ],
+          },
+        },
+      });
+
+      const providers = getEnabledProviders();
+      expect(providers).toHaveLength(2);
+      expect(providers[0]).toEqual({ id: 'google', name: 'Google', type: 'google' });
+      expect(providers[1]).toEqual({ id: 'microsoft', name: 'Microsoft', type: 'microsoft' });
+    });
+  });
+
+  describe('getProviderById', () => {
+    it('should return undefined when provider not found', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [
+              {
+                id: 'google',
+                name: 'Google',
+                type: 'google',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+              },
+            ],
+          },
+        },
+      });
+
+      expect(getProviderById('github')).toBeUndefined();
+    });
+
+    it('should return undefined when provider is disabled', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [
+              {
+                id: 'google',
+                name: 'Google',
+                type: 'google',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+                enabled: false,
+              },
+            ],
+          },
+        },
+      });
+
+      expect(getProviderById('google')).toBeUndefined();
+    });
+
+    it('should return provider when found and enabled', () => {
+      const provider = {
+        id: 'google',
+        name: 'Google',
+        type: 'google' as const,
+        clientId: 'test-client-id',
+        clientSecret: 'test-client-secret',
+      };
+
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [provider],
+          },
+        },
+      });
+
+      expect(getProviderById('google')).toEqual(provider);
+    });
+  });
+
+  describe('generateAuthorizationUrl', () => {
+    it('should return null when provider not found', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [],
+          },
+        },
+      });
+
+      expect(generateAuthorizationUrl('google', 'http://localhost/callback')).toBeNull();
+    });
+
+    it('should generate authorization URL for Google provider', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [
+              {
+                id: 'google',
+                name: 'Google',
+                type: 'google',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+              },
+            ],
+          },
+        },
+      });
+
+      const result = generateAuthorizationUrl('google', 'http://localhost/callback');
+      expect(result).not.toBeNull();
+      expect(result!.url).toContain('https://accounts.google.com/o/oauth2/v2/auth');
+      expect(result!.url).toContain('client_id=test-client-id');
+      expect(result!.url).toContain('redirect_uri=http%3A%2F%2Flocalhost%2Fcallback');
+      expect(result!.url).toContain('response_type=code');
+      expect(result!.url).toContain('scope=openid+email+profile');
+      expect(result!.url).toContain('code_challenge=');
+      expect(result!.state).toBeDefined();
+    });
+
+    it('should generate authorization URL for GitHub provider without PKCE', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [
+              {
+                id: 'github',
+                name: 'GitHub',
+                type: 'github',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+              },
+            ],
+          },
+        },
+      });
+
+      const result = generateAuthorizationUrl('github', 'http://localhost/callback');
+      expect(result).not.toBeNull();
+      expect(result!.url).toContain('https://github.com/login/oauth/authorize');
+      expect(result!.url).not.toContain('code_challenge=');
+      expect(result!.state).toBeDefined();
+    });
+
+    it('should generate authorization URL for Microsoft provider', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [
+              {
+                id: 'microsoft',
+                name: 'Microsoft',
+                type: 'microsoft',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+              },
+            ],
+          },
+        },
+      });
+
+      const result = generateAuthorizationUrl('microsoft', 'http://localhost/callback');
+      expect(result).not.toBeNull();
+      expect(result!.url).toContain('https://login.microsoftonline.com/common/oauth2/v2.0/authorize');
+      expect(result!.url).toContain('code_challenge=');
+      expect(result!.state).toBeDefined();
+    });
+
+    it('should include custom scopes when configured', () => {
+      mockLoadSettings.mockReturnValue({
+        mcpServers: {},
+        systemConfig: {
+          oauthSSO: {
+            enabled: true,
+            providers: [
+              {
+                id: 'google',
+                name: 'Google',
+                type: 'google',
+                clientId: 'test-client-id',
+                clientSecret: 'test-client-secret',
+                scopes: ['custom-scope', 'another-scope'],
+              },
+            ],
+          },
+        },
+      });
+
+      const result = generateAuthorizationUrl('google', 'http://localhost/callback');
+      expect(result).not.toBeNull();
+      expect(result!.url).toContain('scope=custom-scope+another-scope');
+    });
+  });
+});