server/middlewares/activitypub.ts

   1 import { NextFunction, Request, Response, RequestHandler } from 'express'
   2 import { ActivityPubSignature } from '../../shared'
   3 import { isSignatureVerified, logger } from '../helpers'
   4 import { fetchRemoteAccountAndCreateServer } from '../helpers/activitypub'
   5 import { database as db, ACTIVITY_PUB_ACCEPT_HEADER } from '../initializers'
   6 import { each, eachSeries, waterfall } from 'async'
   7
   8 async function checkSignature (req: Request, res: Response, next: NextFunction) {
   9   const signatureObject: ActivityPubSignature = req.body.signature
  10
  11   logger.debug('Checking signature of account %s...', signatureObject.creator)
  12
  13   let account = await db.Account.loadByUrl(signatureObject.creator)
  14
  15   // We don't have this account in our database, fetch it on remote
  16   if (!account) {
  17     const accountResult = await fetchRemoteAccountAndCreateServer(signatureObject.creator)
  18
  19     if (!accountResult) {
  20       return res.sendStatus(403)
  21     }
  22
  23     // Save our new account in database
  24     account = accountResult.account
  25     await account.save()
  26   }
  27
  28   const verified = await isSignatureVerified(account, req.body)
  29   if (verified === false) return res.sendStatus(403)
  30
  31   res.locals.signature = {
  32     account
  33   }
  34
  35   return next()
  36 }
  37
  38 function executeIfActivityPub (fun: RequestHandler | RequestHandler[]) {
  39   return (req: Request, res: Response, next: NextFunction) => {
  40     if (req.header('Accept') !== ACTIVITY_PUB_ACCEPT_HEADER) {
  41       return next()
  42     }
  43
  44     if (Array.isArray(fun) === true) {
  45       return eachSeries(fun as RequestHandler[], (f, cb) => {
  46         f(req, res, cb)
  47       }, next)
  48     }
  49
  50     return (fun as RequestHandler)(req, res, next)
  51   }
  52 }
  53
  54 // ---------------------------------------------------------------------------
  55
  56 export {
  57   checkSignature,
  58   executeIfActivityPub
  59 }