feature: Log authentication failures to support fail2ban. Fixes #477 (#569)

* How do I set the variable "user" or "system" for AI inference #262
changed from system to user

* [Feature Request] Log failed login attempts for fail2ban implementation
#477
added logging of failed logins

* [Feature Request] Log failed login attempts for fail2ban implementation #477
added more logging for extension related logins

* Propagte IP to trpc

---------

Co-authored-by: Your Name <you@example.com>

5 files changed, 59 insertions, 7 deletions

diff --git a/packages/shared/logger.ts b/packages/shared/logger.ts
index f406b447..f3aa3cb9 100644
--- a/packages/shared/logger.ts
+++ b/packages/shared/logger.ts
@@ -15,3 +15,22 @@ const logger = winston.createLogger({
 });
 
 export default logger;
+
+export const authFailureLogger = winston.createLogger({
+  level: "debug",
+  format: winston.format.combine(
+    winston.format.timestamp(),
+    winston.format.printf(
+      (info) => `${info.timestamp} ${info.level}: ${info.message}`,
+    ),
+  ),
+  transports: [
+    new winston.transports.Console(),
+    new winston.transports.File({
+      filename: "auth_failures.log",
+      dirname: serverConfig.dataDir,
+      maxFiles: 2,
+      maxsize: 1024 * 1024,
+    }),
+  ],
+});
diff --git a/packages/trpc/auth.ts b/packages/trpc/auth.ts
index 39aebd3b..1efbdde6 100644
--- a/packages/trpc/auth.ts
+++ b/packages/trpc/auth.ts
@@ -4,6 +4,7 @@ import * as bcrypt from "bcryptjs";
 import { db } from "@hoarder/db";
 import { apiKeys } from "@hoarder/db/schema";
 import serverConfig from "@hoarder/shared/config";
+import { authFailureLogger } from "@hoarder/shared/logger";
 
 // API Keys
 
@@ -102,3 +103,13 @@ export async function validatePassword(email: string, password: string) {
 
   return user;
 }
+
+export function logAuthenticationError(
+  user: string,
+  message: string,
+  ip: string | null,
+): void {
+  authFailureLogger.error(
+    `Authentication error. User: "${user}", Message: "${message}", IP-Address: "${ip}"`,
+  );
+}
diff --git a/packages/trpc/index.ts b/packages/trpc/index.ts
index 5f351a8e..26d8ea96 100644
--- a/packages/trpc/index.ts
+++ b/packages/trpc/index.ts
@@ -15,11 +15,17 @@ interface User {
 export interface Context {
   user: User | null;
   db: typeof db;
+  req: {
+    ip: string | null;
+  };
 }
 
 export interface AuthedContext {
   user: User;
   db: typeof db;
+  req: {
+    ip: string | null;
+  };
 }
 
 // Avoid exporting the entire t-object
diff --git a/packages/trpc/routers/apiKeys.ts b/packages/trpc/routers/apiKeys.ts
index b7468dd2..c55dc095 100644
--- a/packages/trpc/routers/apiKeys.ts
+++ b/packages/trpc/routers/apiKeys.ts
@@ -5,7 +5,12 @@ import { z } from "zod";
 import { apiKeys } from "@hoarder/db/schema";
 import serverConfig from "@hoarder/shared/config";
 
-import { authenticateApiKey, generateApiKey, validatePassword } from "../auth";
+import {
+  authenticateApiKey,
+  generateApiKey,
+  logAuthenticationError,
+  validatePassword,
+} from "../auth";
 import { authedProcedure, publicProcedure, router } from "../index";
 
 const zApiKeySchema = z.object({
@@ -73,7 +78,7 @@ export const apiKeysAppRouter = router({
       }),
     )
     .output(zApiKeySchema)
-    .mutation(async ({ input }) => {
+    .mutation(async ({ input, ctx }) => {
       let user;
       // Special handling as otherwise the extension would show "username or password is wrong"
       if (serverConfig.auth.disablePasswordAuth) {
@@ -85,6 +90,8 @@ export const apiKeysAppRouter = router({
       try {
         user = await validatePassword(input.email, input.password);
       } catch (e) {
+        const error = e as Error;
+        logAuthenticationError(input.email, error.message, ctx.req.ip);
         throw new TRPCError({ code: "UNAUTHORIZED" });
       }
       return await generateApiKey(input.keyName, user.id);
@@ -92,10 +99,16 @@ export const apiKeysAppRouter = router({
   validate: publicProcedure
     .input(z.object({ apiKey: z.string() }))
     .output(z.object({ success: z.boolean() }))
-    .mutation(async ({ input }) => {
-      await authenticateApiKey(input.apiKey); // Throws if the key is invalid
-      return {
-        success: true,
-      };
+    .mutation(async ({ input, ctx }) => {
+      try {
+        await authenticateApiKey(input.apiKey); // Throws if the key is invalid
+        return {
+          success: true,
+        };
+      } catch (e) {
+        const error = e as Error;
+        logAuthenticationError("<unknown>", error.message, ctx.req.ip);
+        throw e;
+      }
     }),
 });
diff --git a/packages/trpc/testUtils.ts b/packages/trpc/testUtils.ts
index 04e6b0a3..23dcdb33 100644
--- a/packages/trpc/testUtils.ts
+++ b/packages/trpc/testUtils.ts
@@ -37,6 +37,9 @@ export function getApiCaller(db: TestDB, userId?: string, email?: string) {
         }
       : null,
     db,
+    req: {
+      ip: null,
+    },
   });
 }