auth api backend changes

- use os.open to create jwt secret with restrictive permissions (0o600: read/write for owner only)
- add backend validation for password strength
- add iat claim to jwt so the server can determine when a token was issued and reject any jwts issued before a user's password_changed_at timestamp, ensuring old tokens are invalidated after a password change
- set logout route to public to avoid 401 when logging out
- issue new jwt for users who change their own password so they stay logged in

frigate/api/auth.py

@@ -8,7 +8,6 @@ import logging
 import os
 import re
 import secrets
-import stat
 import time
 from datetime import datetime
 from pathlib import Path
@@ -312,8 +311,9 @@ def get_jwt_secret() -> str:
             )
             jwt_secret = secrets.token_hex(64)
             try:
-                # Use os.open to create file with restrictive permissions (0o600: read/write for owner only)
-                fd = os.open(jwt_secret_file, os.O_WRONLY | os.O_CREAT | os.O_EXCL, 0o600)
+                fd = os.open(
+                    jwt_secret_file, os.O_WRONLY | os.O_CREAT | os.O_EXCL, 0o600
+                )
                 with os.fdopen(fd, "w") as f:
                     f.write(str(jwt_secret))
             except Exception:
@@ -359,9 +359,35 @@ def verify_password(password, password_hash):
     return secrets.compare_digest(password_hash, compare_hash)
 
 
+def validate_password_strength(password: str) -> tuple[bool, Optional[str]]:
+    """
+    Validate password strength.
+
+    Returns a tuple of (is_valid, error_message).
+    """
+    if not password:
+        return False, "Password cannot be empty"
+
+    if len(password) < 8:
+        return False, "Password must be at least 8 characters long"
+
+    if not any(c.isupper() for c in password):
+        return False, "Password must contain at least one uppercase letter"
+
+    if not any(c.isdigit() for c in password):
+        return False, "Password must contain at least one digit"
+
+    if not any(c in '!@#$%^&*(),.?":{}|<>' for c in password):
+        return False, "Password must contain at least one special character"
+
+    return True, None
+
+
 def create_encoded_jwt(user, role, expiration, secret):
     return jwt.encode(
-        {"alg": "HS256"}, {"sub": user, "role": role, "exp": expiration}, secret
+        {"alg": "HS256"},
+        {"sub": user, "role": role, "exp": expiration, "iat": int(time.time())},
+        secret,
     )
 
 
@@ -621,14 +647,27 @@ def auth(request: Request):
             logger.debug("jwt token expired")
             return fail_response
 
+        # Check if password has been changed after token was issued
+        try:
+            user_obj = User.get_by_id(user)
+            # Only invalidate token if password was changed after token was issued
+            if user_obj.password_changed_at is not None:
+                token_iat = int(token.claims.get("iat", 0))
+                password_changed_timestamp = int(
+                    user_obj.password_changed_at.timestamp()
+                )
+                if token_iat < password_changed_timestamp:
+                    logger.debug(
+                        "jwt token issued before password change, invalidating token"
+                    )
+                    return fail_response
+        except DoesNotExist:
+            logger.debug("user not found")
+            return fail_response
+
         # if the jwt cookie is expiring soon
-        elif jwt_source == "cookie" and expiration - JWT_REFRESH <= current_time:
+        if jwt_source == "cookie" and expiration - JWT_REFRESH <= current_time:
             logger.debug("jwt token expiring soon, refreshing cookie")
-            # ensure the user hasn't been deleted
-            try:
-                User.get_by_id(user)
-            except DoesNotExist:
-                return fail_response
             new_expiration = current_time + JWT_SESSION_LENGTH
             new_encoded_jwt = create_encoded_jwt(
                 user, role, new_expiration, request.app.jwt_token
@@ -663,7 +702,7 @@ def profile(request: Request):
     )
 
 
-@router.get("/logout", dependencies=[Depends(allow_any_authenticated())])
+@router.get("/logout", dependencies=[Depends(allow_public())])
 def logout(request: Request):
     auth_config: AuthConfig = request.app.frigate_config.auth
     response = RedirectResponse("/login", status_code=303)
@@ -785,8 +824,60 @@ async def update_password(
 
     HASH_ITERATIONS = request.app.frigate_config.auth.hash_iterations
 
+    try:
+        user = User.get_by_id(username)
+    except DoesNotExist:
+        return JSONResponse(content={"message": "User not found"}, status_code=404)
+
+    # Require old_password when:
+    # 1. Non-admin user is changing another user's password (admin only action)
+    # 2. Any user is changing their own password
+    is_changing_own_password = current_username == username
+    is_non_admin = current_role != "admin"
+
+    if is_changing_own_password or is_non_admin:
+        if not body.old_password:
+            return JSONResponse(
+                content={"message": "Current password is required"},
+                status_code=400,
+            )
+        if not verify_password(body.old_password, user.password_hash):
+            return JSONResponse(
+                content={"message": "Current password is incorrect"},
+                status_code=401,
+            )
+
+    # Validate new password strength
+    is_valid, error_message = validate_password_strength(body.password)
+    if not is_valid:
+        return JSONResponse(
+            content={"message": error_message},
+            status_code=400,
+        )
+
     password_hash = hash_password(body.password, iterations=HASH_ITERATIONS)
-    User.set_by_id(username, {User.password_hash: password_hash})
+    User.update(
+        {
+            User.password_hash: password_hash,
+            User.password_changed_at: datetime.now(),
+        }
+    ).where(User.username == username).execute()
+
+    # If user changed their own password, issue a new JWT to keep them logged in
+    if current_username == username:
+        JWT_COOKIE_NAME = request.app.frigate_config.auth.cookie_name
+        JWT_COOKIE_SECURE = request.app.frigate_config.auth.cookie_secure
+        JWT_SESSION_LENGTH = request.app.frigate_config.auth.session_length
+
+        expiration = int(time.time()) + JWT_SESSION_LENGTH
+        encoded_jwt = create_encoded_jwt(
+            username, current_role, expiration, request.app.jwt_token
+        )
+        response = JSONResponse(content={"success": True})
+        set_jwt_cookie(
+            response, JWT_COOKIE_NAME, encoded_jwt, expiration, JWT_COOKIE_SECURE
+        )
+        return response
 
     return JSONResponse(content={"success": True})