Refactor auth flow

Reimplement some node-oauth2-server methods to remove hacky code needed by our external
login workflow

1 files changed, 219 insertions, 0 deletions

diff --git a/server/lib/auth/external-auth.ts b/server/lib/auth/external-auth.ts
new file mode 100644
index 000000000..80f5064b6
--- /dev/null
+++ b/server/lib/auth/external-auth.ts
@@ -0,0 +1,219 @@
+
+import { isUserDisplayNameValid, isUserRoleValid, isUserUsernameValid } from '@server/helpers/custom-validators/users'
+import { logger } from '@server/helpers/logger'
+import { generateRandomString } from '@server/helpers/utils'
+import { PLUGIN_EXTERNAL_AUTH_TOKEN_LIFETIME } from '@server/initializers/constants'
+import { PluginManager } from '@server/lib/plugins/plugin-manager'
+import { OAuthTokenModel } from '@server/models/oauth/oauth-token'
+import {
+  RegisterServerAuthenticatedResult,
+  RegisterServerAuthPassOptions,
+  RegisterServerExternalAuthenticatedResult
+} from '@server/types/plugins/register-server-auth.model'
+import { UserRole } from '@shared/models'
+
+// Token is the key, expiration date is the value
+const authBypassTokens = new Map<string, {
+  expires: Date
+  user: {
+    username: string
+    email: string
+    displayName: string
+    role: UserRole
+  }
+  authName: string
+  npmName: string
+}>()
+
+async function onExternalUserAuthenticated (options: {
+  npmName: string
+  authName: string
+  authResult: RegisterServerExternalAuthenticatedResult
+}) {
+  const { npmName, authName, authResult } = options
+
+  if (!authResult.req || !authResult.res) {
+    logger.error('Cannot authenticate external user for auth %s of plugin %s: no req or res are provided.', authName, npmName)
+    return
+  }
+
+  const { res } = authResult
+
+  if (!isAuthResultValid(npmName, authName, authResult)) {
+    res.redirect('/login?externalAuthError=true')
+    return
+  }
+
+  logger.info('Generating auth bypass token for %s in auth %s of plugin %s.', authResult.username, authName, npmName)
+
+  const bypassToken = await generateRandomString(32)
+
+  const expires = new Date()
+  expires.setTime(expires.getTime() + PLUGIN_EXTERNAL_AUTH_TOKEN_LIFETIME)
+
+  const user = buildUserResult(authResult)
+  authBypassTokens.set(bypassToken, {
+    expires,
+    user,
+    npmName,
+    authName
+  })
+
+  // Cleanup expired tokens
+  const now = new Date()
+  for (const [ key, value ] of authBypassTokens) {
+    if (value.expires.getTime() < now.getTime()) {
+      authBypassTokens.delete(key)
+    }
+  }
+
+  res.redirect(`/login?externalAuthToken=${bypassToken}&username=${user.username}`)
+}
+
+async function getAuthNameFromRefreshGrant (refreshToken?: string) {
+  if (!refreshToken) return undefined
+
+  const tokenModel = await OAuthTokenModel.loadByRefreshToken(refreshToken)
+
+  return tokenModel?.authName
+}
+
+async function getBypassFromPasswordGrant (username: string, password: string) {
+  const plugins = PluginManager.Instance.getIdAndPassAuths()
+  const pluginAuths: { npmName?: string, registerAuthOptions: RegisterServerAuthPassOptions }[] = []
+
+  for (const plugin of plugins) {
+    const auths = plugin.idAndPassAuths
+
+    for (const auth of auths) {
+      pluginAuths.push({
+        npmName: plugin.npmName,
+        registerAuthOptions: auth
+      })
+    }
+  }
+
+  pluginAuths.sort((a, b) => {
+    const aWeight = a.registerAuthOptions.getWeight()
+    const bWeight = b.registerAuthOptions.getWeight()
+
+    // DESC weight order
+    if (aWeight === bWeight) return 0
+    if (aWeight < bWeight) return 1
+    return -1
+  })
+
+  const loginOptions = {
+    id: username,
+    password
+  }
+
+  for (const pluginAuth of pluginAuths) {
+    const authOptions = pluginAuth.registerAuthOptions
+    const authName = authOptions.authName
+    const npmName = pluginAuth.npmName
+
+    logger.debug(
+      'Using auth method %s of plugin %s to login %s with weight %d.',
+      authName, npmName, loginOptions.id, authOptions.getWeight()
+    )
+
+    try {
+      const loginResult = await authOptions.login(loginOptions)
+
+      if (!loginResult) continue
+      if (!isAuthResultValid(pluginAuth.npmName, authOptions.authName, loginResult)) continue
+
+      logger.info(
+        'Login success with auth method %s of plugin %s for %s.',
+        authName, npmName, loginOptions.id
+      )
+
+      return {
+        bypass: true,
+        pluginName: pluginAuth.npmName,
+        authName: authOptions.authName,
+        user: buildUserResult(loginResult)
+      }
+    } catch (err) {
+      logger.error('Error in auth method %s of plugin %s', authOptions.authName, pluginAuth.npmName, { err })
+    }
+  }
+
+  return undefined
+}
+
+function getBypassFromExternalAuth (username: string, externalAuthToken: string) {
+  const obj = authBypassTokens.get(externalAuthToken)
+  if (!obj) throw new Error('Cannot authenticate user with unknown bypass token')
+
+  const { expires, user, authName, npmName } = obj
+
+  const now = new Date()
+  if (now.getTime() > expires.getTime()) {
+    throw new Error('Cannot authenticate user with an expired external auth token')
+  }
+
+  if (user.username !== username) {
+    throw new Error(`Cannot authenticate user ${user.username} with invalid username ${username}`)
+  }
+
+  logger.info(
+    'Auth success with external auth method %s of plugin %s for %s.',
+    authName, npmName, user.email
+  )
+
+  return {
+    bypass: true,
+    pluginName: npmName,
+    authName: authName,
+    user
+  }
+}
+
+function isAuthResultValid (npmName: string, authName: string, result: RegisterServerAuthenticatedResult) {
+  if (!isUserUsernameValid(result.username)) {
+    logger.error('Auth method %s of plugin %s did not provide a valid username.', authName, npmName, { username: result.username })
+    return false
+  }
+
+  if (!result.email) {
+    logger.error('Auth method %s of plugin %s did not provide a valid email.', authName, npmName, { email: result.email })
+    return false
+  }
+
+  // role is optional
+  if (result.role && !isUserRoleValid(result.role)) {
+    logger.error('Auth method %s of plugin %s did not provide a valid role.', authName, npmName, { role: result.role })
+    return false
+  }
+
+  // display name is optional
+  if (result.displayName && !isUserDisplayNameValid(result.displayName)) {
+    logger.error(
+      'Auth method %s of plugin %s did not provide a valid display name.',
+      authName, npmName, { displayName: result.displayName }
+    )
+    return false
+  }
+
+  return true
+}
+
+function buildUserResult (pluginResult: RegisterServerAuthenticatedResult) {
+  return {
+    username: pluginResult.username,
+    email: pluginResult.email,
+    role: pluginResult.role ?? UserRole.USER,
+    displayName: pluginResult.displayName || pluginResult.username
+  }
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  onExternalUserAuthenticated,
+  getBypassFromExternalAuth,
+  getAuthNameFromRefreshGrant,
+  getBypassFromPasswordGrant
+}