KI-AGENT: Persistente App-Sessions mit Refresh-Tokens ergänzen

backend/src/routes/auth/auth.ts

@@ -1,14 +1,18 @@
 import { FastifyInstance } from "fastify";
 import bcrypt from "bcrypt";
-import jwt from "jsonwebtoken";
 import { generateRandomPassword, hashPassword } from "../../utils/password";
 import { sendMail } from "../../utils/mailer";
-import { secrets } from "../../utils/secrets";
 
 import { authUsers } from "../../../db/schema";
 import { authTenantUsers } from "../../../db/schema";
 import { tenants } from "../../../db/schema";
-import { eq, and } from "drizzle-orm";
+import { eq } from "drizzle-orm";
+import {
+    createAccessToken,
+    issueRefreshToken,
+    revokeRefreshToken,
+    rotateRefreshToken,
+} from "../../utils/authTokens";
 
 export default async function authRoutes(server: FastifyInstance) {
 
@@ -122,15 +126,9 @@ export default async function authRoutes(server: FastifyInstance) {
             return reply.code(401).send({ error: "Invalid credentials" });
         }
 
-        const token = jwt.sign(
-            {
-                user_id: user.id,
-                email: user.email,
-                tenant_id: req.tenant?.id ?? null,
-            },
-            secrets.JWT_SECRET!,
-            { expiresIn: "6h" }
-        );
+        const tenantId = req.tenant?.id ? Number(req.tenant.id) : null;
+        const token = createAccessToken(user, tenantId);
+        const refreshToken = await issueRefreshToken(server, user.id, tenantId);
 
         reply.setCookie("token", token, {
             path: "/",
@@ -140,9 +138,31 @@ export default async function authRoutes(server: FastifyInstance) {
             maxAge: 60 * 60 * 6,
         });
 
-        return { token };
+        return { token, refreshToken };
     });
 
+    server.post("/auth/refresh", {
+        schema: {
+            tags: ["Auth"],
+            summary: "Refresh a persistent session",
+            body: {
+                type: "object",
+                required: ["refreshToken"],
+                properties: {
+                    refreshToken: { type: "string" },
+                },
+            },
+        },
+    }, async (req, reply) => {
+        const { refreshToken } = req.body as { refreshToken: string };
+        const refreshed = await rotateRefreshToken(server, refreshToken);
+
+        if (!refreshed) {
+            return reply.code(401).send({ error: "Invalid or expired refresh token" });
+        }
+
+        return refreshed;
+    });
 
     // -----------------------------------------------------
     // LOGOUT
@@ -153,6 +173,10 @@ export default async function authRoutes(server: FastifyInstance) {
             summary: "Logout User"
         }
     }, async (req, reply) => {
+        const refreshToken = (req.body as { refreshToken?: string } | undefined)?.refreshToken;
+        if (refreshToken) {
+            await revokeRefreshToken(server, refreshToken);
+        }
         reply.clearCookie("token", {
             path: "/",
             httpOnly: true,

backend/src/routes/tenant.ts

@@ -14,6 +14,7 @@ import {
 import {and, desc, eq, inArray} from "drizzle-orm"
 import { enrichProfilesWithBranches } from "../utils/profileBranches"
 import { enrichProfilesWithTeams } from "../utils/profileTeams"
+import { rotateRefreshToken } from "../utils/authTokens"
 
 
 export default async function tenantRoutes(server: FastifyInstance) {
@@ -65,7 +66,7 @@ export default async function tenantRoutes(server: FastifyInstance) {
                 return reply.code(401).send({ error: "Unauthorized" })
             }
 
-            const { tenant_id } = req.body as { tenant_id: string }
+            const { tenant_id, refreshToken } = req.body as { tenant_id: string; refreshToken?: string }
             if (!tenant_id) return reply.code(400).send({ error: "tenant_id required" })
 
             // prüfen ob der User zu diesem Tenant gehört
@@ -81,7 +82,22 @@ export default async function tenantRoutes(server: FastifyInstance) {
                 return reply.code(403).send({ error: "Not a member of this tenant" })
             }
 
-            // JWT neu erzeugen
+            if (refreshToken) {
+                const session = await rotateRefreshToken(
+                    server,
+                    refreshToken,
+                    Number(tenant_id),
+                    req.user.user_id
+                )
+
+                if (!session) {
+                    return reply.code(401).send({ error: "Invalid or expired refresh token" })
+                }
+
+                return session
+            }
+
+            // Abwärtskompatibilität für Clients ohne persistente Session
             const token = jwt.sign(
                 {
                     user_id: req.user.user_id,

backend/src/utils/authTokens.ts

@@ -0,0 +1,93 @@
+import { createHash, randomBytes } from "node:crypto"
+import jwt from "jsonwebtoken"
+import { FastifyInstance } from "fastify"
+import { and, eq, gt, isNull } from "drizzle-orm"
+
+import { authRefreshTokens, authUsers } from "../../db/schema"
+import { secrets } from "./secrets"
+
+const ACCESS_TOKEN_TTL_SECONDS = 60 * 60 * 6
+const REFRESH_TOKEN_TTL_DAYS = 90
+
+export function createAccessToken(user: { id: string; email: string }, tenantId: number | null) {
+    return jwt.sign(
+        {
+            user_id: user.id,
+            email: user.email,
+            tenant_id: tenantId,
+        },
+        secrets.JWT_SECRET!,
+        { expiresIn: ACCESS_TOKEN_TTL_SECONDS }
+    )
+}
+
+export function hashRefreshToken(token: string) {
+    return createHash("sha256").update(token, "utf8").digest("hex")
+}
+
+export async function issueRefreshToken(
+    server: FastifyInstance,
+    userId: string,
+    tenantId: number | null
+) {
+    const token = randomBytes(48).toString("base64url")
+    const expiresAt = new Date(Date.now() + REFRESH_TOKEN_TTL_DAYS * 24 * 60 * 60 * 1000)
+
+    await server.db.insert(authRefreshTokens).values({
+        userId,
+        tenantId,
+        tokenHash: hashRefreshToken(token),
+        expiresAt,
+    })
+
+    return token
+}
+
+export async function rotateRefreshToken(
+    server: FastifyInstance,
+    token: string,
+    tenantOverride?: number | null,
+    expectedUserId?: string
+) {
+    const tokenHash = hashRefreshToken(token)
+    const [session] = await server.db
+        .update(authRefreshTokens)
+        .set({ revokedAt: new Date() })
+        .where(and(
+            eq(authRefreshTokens.tokenHash, tokenHash),
+            isNull(authRefreshTokens.revokedAt),
+            gt(authRefreshTokens.expiresAt, new Date())
+        ))
+        .returning({
+            id: authRefreshTokens.id,
+            userId: authRefreshTokens.userId,
+            tenantId: authRefreshTokens.tenantId,
+        })
+
+    if (!session) return null
+    if (expectedUserId && session.userId !== expectedUserId) return null
+
+    const [user] = await server.db
+        .select({ id: authUsers.id, email: authUsers.email })
+        .from(authUsers)
+        .where(eq(authUsers.id, session.userId))
+        .limit(1)
+
+    if (!user) return null
+
+    const tenantId = tenantOverride === undefined ? session.tenantId : tenantOverride
+    const refreshToken = await issueRefreshToken(server, session.userId, tenantId)
+    const accessToken = createAccessToken(user, tenantId)
+
+    return { token: accessToken, refreshToken }
+}
+
+export async function revokeRefreshToken(server: FastifyInstance, token: string) {
+    await server.db
+        .update(authRefreshTokens)
+        .set({ revokedAt: new Date() })
+        .where(and(
+            eq(authRefreshTokens.tokenHash, hashRefreshToken(token)),
+            isNull(authRefreshTokens.revokedAt)
+        ))
+}