feat: prevent brute force attack by rate limiting login endpoint

api/.env.example

@@ -24,6 +24,9 @@ LDAP_BIND_PASSWORD = <password>
 LDAP_USERS_BASE_DN = <ou=users,dc=cloudron>
 LDAP_GROUPS_BASE_DN = <ou=groups,dc=cloudron>
 
+MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY=[100] default value is 100
+MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP=[10] default value is 10 
+
 RUN_TIMES=[sas,js,py | js,py | sas | sas,js] default considered as sas
 SAS_PATH=/opt/sas/sas9/SASHome/SASFoundation/9.4/sas
 NODE_PATH=~/.nvm/versions/node/v16.14.0/bin/node

api/package-lock.json

@@ -24,6 +24,7 @@
         "mongoose-sequence": "^5.3.1",
         "morgan": "^1.10.0",
         "multer": "^1.4.5-lts.1",
+        "rate-limiter-flexible": "2.4.1",
         "rotating-file-stream": "^3.0.4",
         "swagger-ui-express": "4.3.0",
         "unzipper": "^0.10.11",
@@ -9594,6 +9595,11 @@
         "node": ">= 0.6"
       }
     },
+    "node_modules/rate-limiter-flexible": {
+      "version": "2.4.1",
+      "resolved": "https://registry.npmjs.org/rate-limiter-flexible/-/rate-limiter-flexible-2.4.1.tgz",
+      "integrity": "sha512-dgH4T44TzKVO9CLArNto62hJOwlWJMLUjVVr/ii0uUzZXEXthDNr7/yefW5z/1vvHAfycc1tnuiYyNJ8CTRB3g=="
+    },
     "node_modules/raw-body": {
       "version": "2.5.1",
       "resolved": "https://registry.npmjs.org/raw-body/-/raw-body-2.5.1.tgz",
@@ -18811,6 +18817,11 @@
       "resolved": "https://registry.npmjs.org/range-parser/-/range-parser-1.2.1.tgz",
       "integrity": "sha512-Hrgsx+orqoygnmhFbKaHE6c296J+HTAQXoxEF6gNupROmmGJRoyzfG3ccAveqCBrwr/2yxQ5BVd/GTl5agOwSg=="
     },
+    "rate-limiter-flexible": {
+      "version": "2.4.1",
+      "resolved": "https://registry.npmjs.org/rate-limiter-flexible/-/rate-limiter-flexible-2.4.1.tgz",
+      "integrity": "sha512-dgH4T44TzKVO9CLArNto62hJOwlWJMLUjVVr/ii0uUzZXEXthDNr7/yefW5z/1vvHAfycc1tnuiYyNJ8CTRB3g=="
+    },
     "raw-body": {
       "version": "2.5.1",
       "resolved": "https://registry.npmjs.org/raw-body/-/raw-body-2.5.1.tgz",

api/package.json

@@ -64,6 +64,7 @@
     "mongoose-sequence": "^5.3.1",
     "morgan": "^1.10.0",
     "multer": "^1.4.5-lts.1",
+    "rate-limiter-flexible": "2.4.1",
     "rotating-file-stream": "^3.0.4",
     "swagger-ui-express": "4.3.0",
     "unzipper": "^0.10.11",

api/src/controllers/web.ts

@@ -8,8 +8,10 @@ import Client from '../model/Client'
 import {
   getWebBuildFolder,
   generateAuthCode,
+  getRateLimiters,
   AuthProviderType,
-  LDAPClient
+  LDAPClient,
+  secondsToHms
 } from '../utils'
 import { InfoJWT } from '../types'
 import { AuthController } from './auth'
@@ -81,19 +83,98 @@ const login = async (
   req: express.Request,
   { username, password }: LoginPayload
 ) => {
+  // code for preventing brute force attack
+
+  const {
+    MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY,
+    MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP
+  } = process.env
+
+  const { limiterSlowBruteByIP, limiterConsecutiveFailsByUsernameAndIP } =
+    getRateLimiters()
+
+  const ipAddr = req.ip
+  const usernameIPkey = getUsernameIPkey(username, ipAddr)
+
+  const [resSlowByIP, resUsernameAndIP] = await Promise.all([
+    limiterSlowBruteByIP.get(ipAddr),
+    limiterConsecutiveFailsByUsernameAndIP.get(usernameIPkey)
+  ])
+
+  let retrySecs = 0
+
+  // Check if IP or Username + IP is already blocked
+  if (
+    resSlowByIP !== null &&
+    resSlowByIP.consumedPoints >= Number(MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY)
+  ) {
+    retrySecs = Math.round(resSlowByIP.msBeforeNext / 1000) || 1
+  } else if (
+    resUsernameAndIP !== null &&
+    resUsernameAndIP.consumedPoints >=
+      Number(MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP)
+  ) {
+    retrySecs = Math.round(resUsernameAndIP.msBeforeNext / 1000) || 1
+  }
+
+  if (retrySecs > 0) {
+    throw {
+      code: 429,
+      message: `Too Many Requests! Retry after ${secondsToHms(retrySecs)}`
+    }
+  }
+
   // Authenticate User
   const user = await User.findOne({ username })
-  if (!user) throw new Error('Username is not found.')
 
-  if (
-    process.env.AUTH_PROVIDERS === AuthProviderType.LDAP &&
-    user.authProvider === AuthProviderType.LDAP
-  ) {
-    const ldapClient = await LDAPClient.init()
-    await ldapClient.verifyUser(username, password)
-  } else {
-    const validPass = user.comparePassword(password)
-    if (!validPass) throw new Error('Invalid password.')
+  let validPass = false
+
+  if (user) {
+    if (
+      process.env.AUTH_PROVIDERS === AuthProviderType.LDAP &&
+      user.authProvider === AuthProviderType.LDAP
+    ) {
+      const ldapClient = await LDAPClient.init()
+      validPass = await ldapClient
+        .verifyUser(username, password)
+        .catch(() => false)
+    } else {
+      validPass = user.comparePassword(password)
+    }
+  }
+
+  // Consume 1 point from limiters on wrong attempt and block if limits reached
+  if (!validPass) {
+    try {
+      const promises = [limiterSlowBruteByIP.consume(ipAddr)]
+      if (user) {
+        // Count failed attempts by Username + IP only for registered users
+        promises.push(
+          limiterConsecutiveFailsByUsernameAndIP.consume(usernameIPkey)
+        )
+      }
+
+      await Promise.all(promises)
+    } catch (rlRejected: any) {
+      if (rlRejected instanceof Error) {
+        throw rlRejected
+      } else {
+        retrySecs = Math.round(rlRejected.msBeforeNext / 1000) || 1
+
+        throw {
+          code: 429,
+          message: `Too Many Requests! Retry after ${secondsToHms(retrySecs)}`
+        }
+      }
+    }
+  }
+
+  if (!user) throw { code: 401, message: 'Username is not found.' }
+  if (!validPass) throw { code: 401, message: 'Invalid Password.' }
+
+  if (resUsernameAndIP !== null && resUsernameAndIP.consumedPoints > 0) {
+    // Reset on successful authorization
+    await limiterConsecutiveFailsByUsernameAndIP.delete(usernameIPkey)
   }
 
   req.session.loggedIn = true
@@ -144,6 +225,8 @@ const authorize = async (
   return { code }
 }
 
+const getUsernameIPkey = (username: string, ip: string) => `${username}_${ip}`
+
 interface LoginPayload {
   /**
    * Username for user

api/src/routes/api/spec/web.spec.ts

@@ -47,7 +47,7 @@ describe('web', () => {
     })
   })
 
-  describe('SASLogon/login', () => {
+  describe.only('SASLogon/login', () => {
     let csrfToken: string
 
     beforeAll(async () => {
@@ -63,6 +63,7 @@ describe('web', () => {
     it('should respond with successful login', async () => {
       await userController.createUser(user)
 
+      process.dbInstance = con
       const res = await request(app)
         .post('/SASLogon/login')
         .set('x-xsrf-token', csrfToken)
@@ -82,6 +83,72 @@ describe('web', () => {
       })
     })
 
+    it('should respond with too many requests when attempting with invalid password for a same user 10 times', async () => {
+      await userController.createUser(user)
+
+      process.dbInstance = con
+
+      const promises: request.Test[] = []
+
+      Array(10)
+        .fill(0)
+        .map((_, i) => {
+          promises.push(
+            request(app)
+              .post('/SASLogon/login')
+              .set('x-xsrf-token', csrfToken)
+              .send({
+                username: user.username,
+                password: 'invalid-password'
+              })
+          )
+        })
+
+      await Promise.all(promises)
+
+      const res = await request(app)
+        .post('/SASLogon/login')
+        .set('x-xsrf-token', csrfToken)
+        .send({
+          username: user.username,
+          password: user.password
+        })
+        .expect(429)
+    })
+
+    it.only('should respond with too many requests when attempting with invalid credentials for different users but with same ip 100 times', async () => {
+      await userController.createUser(user)
+
+      process.dbInstance = con
+
+      const promises: request.Test[] = []
+
+      Array(100)
+        .fill(0)
+        .map((_, i) => {
+          promises.push(
+            request(app)
+              .post('/SASLogon/login')
+              .set('x-xsrf-token', csrfToken)
+              .send({
+                username: `user${i}`,
+                password: 'invalid-password'
+              })
+          )
+        })
+
+      await Promise.all(promises)
+
+      const res = await request(app)
+        .post('/SASLogon/login')
+        .set('x-xsrf-token', csrfToken)
+        .send({
+          username: user.username,
+          password: user.password
+        })
+        .expect(429)
+    })
+
     it('should respond with Bad Request if CSRF Token is not present', async () => {
       await userController.createUser(user)
 

api/src/routes/web/web.ts

@@ -35,7 +35,11 @@ webRouter.post('/SASLogon/login', desktopRestrict, async (req, res) => {
     const response = await controller.login(req, body)
     res.send(response)
   } catch (err: any) {
-    res.status(403).send(err.toString())
+    if (err instanceof Error) {
+      res.status(500).send(err.toString())
+    } else {
+      res.status(err.code).send(err.message)
+    }
   }
 })
 

api/src/types/system/process.d.ts

@@ -14,5 +14,6 @@ declare namespace NodeJS {
     logger: import('@sasjs/utils/logger').Logger
     runTimes: import('../../utils').RunTimeType[]
     secrets: import('../../model/Configuration').ConfigurationType
+    dbInstance: import('mongoose').Mongoose
   }
 }

api/src/utils/connectDB.ts

@@ -3,7 +3,9 @@ import { seedDB } from './seedDB'
 
 export const connectDB = async () => {
   try {
-    await mongoose.connect(process.env.DB_CONNECT as string)
+    process.dbInstance = await mongoose.connect(
+      process.env.DB_CONNECT as string
+    )
   } catch (err) {
     throw new Error('Unable to connect to DB!')
   }

api/src/utils/getRateLimiters.ts

@@ -0,0 +1,26 @@
+import { RateLimiterMongo } from 'rate-limiter-flexible'
+
+export const getRateLimiters = () => {
+  const {
+    MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY,
+    MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP
+  } = process.env
+
+  const limiterSlowBruteByIP = new RateLimiterMongo({
+    storeClient: process.dbInstance.connection,
+    keyPrefix: 'login_fail_ip_per_day',
+    points: Number(MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY),
+    duration: 60 * 60 * 24,
+    blockDuration: 60 * 60 * 24 // Block for 1 day
+  })
+
+  const limiterConsecutiveFailsByUsernameAndIP = new RateLimiterMongo({
+    storeClient: process.dbInstance.connection,
+    keyPrefix: 'login_fail_consecutive_username_and_ip',
+    points: Number(MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP),
+    duration: 60 * 60 * 24 * 90, // Store number for 90 days since first fail
+    blockDuration: 60 * 60 // Block for 1 hour
+  })
+
+  return { limiterSlowBruteByIP, limiterConsecutiveFailsByUsernameAndIP }
+}

api/src/utils/index.ts

@@ -13,6 +13,7 @@ export * from './getAuthorizedRoutes'
 export * from './getCertificates'
 export * from './getDesktopFields'
 export * from './getPreProgramVariables'
+export * from './getRateLimiters'
 export * from './getRunTimeAndFilePath'
 export * from './getServerUrl'
 export * from './getTokensFromDB'
@@ -20,10 +21,10 @@ export * from './instantiateLogger'
 export * from './isDebugOn'
 export * from './isPublicRoute'
 export * from './ldapClient'
-export * from './zipped'
 export * from './parseLogToArray'
 export * from './removeTokensInDB'
 export * from './saveTokensInDB'
+export * from './secondsToHms'
 export * from './seedDB'
 export * from './setProcessVariables'
 export * from './setupFolders'
@@ -32,3 +33,4 @@ export * from './upload'
 export * from './validation'
 export * from './verifyEnvVariables'
 export * from './verifyTokenInDB'
+export * from './zipped'

api/src/utils/secondsToHms.ts

@@ -0,0 +1,10 @@
+export const secondsToHms = (seconds: number) => {
+  const h = Math.floor(seconds / 3600)
+  const m = Math.floor((seconds % 3600) / 60)
+  const s = Math.floor((seconds % 3600) % 60)
+
+  const hDisplay = h > 0 ? h + (h == 1 ? ' hour, ' : ' hours, ') : ''
+  const mDisplay = m > 0 ? m + (m == 1 ? ' minute, ' : ' minutes, ') : ''
+  const sDisplay = s > 0 ? s + (s == 1 ? ' second' : ' seconds') : ''
+  return hDisplay + mDisplay + sDisplay
+}

api/src/utils/verifyEnvVariables.ts

@@ -77,6 +77,8 @@ export const verifyEnvVariables = (): ReturnCode => {
 
   errors.push(...verifyDbType())
 
+  errors.push(...verifyRateLimiter())
+
   if (errors.length) {
     process.logger?.error(
       `Invalid environment variable(s) provided: \n${errors.join('\n')}`
@@ -367,6 +369,50 @@ const verifyDbType = () => {
   return errors
 }
 
+const verifyRateLimiter = () => {
+  const errors: string[] = []
+  const {
+    MODE,
+    MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY,
+    MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP
+  } = process.env
+  if (MODE === ModeType.Server) {
+    if (MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY) {
+      if (
+        !isNumeric(MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY) ||
+        Number(MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY) < 1
+      ) {
+        errors.push(
+          `- Invalid value for 'MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY' - Only positive number is acceptable`
+        )
+      }
+    } else {
+      process.env.MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY =
+        DEFAULTS.MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY
+    }
+
+    if (MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP) {
+      if (
+        !isNumeric(MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP) ||
+        Number(MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP) < 1
+      ) {
+        errors.push(
+          `- Invalid value for 'MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP' - Only positive number is acceptable`
+        )
+      }
+    } else {
+      process.env.MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP =
+        DEFAULTS.MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP
+    }
+  }
+
+  return errors
+}
+
+const isNumeric = (val: string): boolean => {
+  return !isNaN(Number(val))
+}
+
 const DEFAULTS = {
   MODE: ModeType.Desktop,
   PROTOCOL: ProtocolType.HTTP,
@@ -374,5 +420,7 @@ const DEFAULTS = {
   HELMET_COEP: HelmetCoepType.TRUE,
   LOG_FORMAT_MORGAN: LOG_FORMAT_MORGANType.Common,
   RUN_TIMES: RunTimeType.SAS,
-  DB_TYPE: DatabaseType.MONGO
+  DB_TYPE: DatabaseType.MONGO,
+  MAX_WRONG_ATTEMPTS_BY_IP_PER_DAY: '100',
+  MAX_CONSECUTIVE_FAILS_BY_USERNAME_AND_IP: '10'
 }