server/middlewares/activitypub.ts

   1 import { eachSeries } from 'async'
   2 import { NextFunction, Request, RequestHandler, Response } from 'express'
   3 import { ActivityPubSignature } from '../../shared'
   4 import { isSignatureVerified, logger } from '../helpers'
   5 import { database as db } from '../initializers'
   6 import { ACTIVITY_PUB } from '../initializers/constants'
   7 import { fetchRemoteAccount, saveAccountAndServerIfNotExist } from '../lib/activitypub/account'
   8
   9 async function checkSignature (req: Request, res: Response, next: NextFunction) {
  10   const signatureObject: ActivityPubSignature = req.body.signature
  11
  12   logger.debug('Checking signature of account %s...', signatureObject.creator)
  13
  14   let account = await db.Account.loadByUrl(signatureObject.creator)
  15
  16   // We don't have this account in our database, fetch it on remote
  17   if (!account) {
  18     account = await fetchRemoteAccount(signatureObject.creator)
  19
  20     if (!account) {
  21       return res.sendStatus(403)
  22     }
  23
  24     // Save our new account and its server in database
  25     await saveAccountAndServerIfNotExist(account)
  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 (ACTIVITY_PUB.ACCEPT_HEADERS.indexOf(req.header('Accept')) === -1) {
  41       return next()
  42     }
  43
  44     logger.debug('ActivityPub request for %s.', req.url)
  45
  46     if (Array.isArray(fun) === true) {
  47       return eachSeries(fun as RequestHandler[], (f, cb) => {
  48         f(req, res, cb)
  49       }, next)
  50     }
  51
  52     return (fun as RequestHandler)(req, res, next)
  53   }
  54 }
  55
  56 // ---------------------------------------------------------------------------
  57
  58 export {
  59   checkSignature,
  60   executeIfActivityPub
  61 }