peertube/server/middlewares/secure.ts

import 'express-validator'
import * as express from 'express'

import { database as db } from '../initializers'
import {
  logger,
  checkSignature as peertubeCryptoCheckSignature
} from '../helpers'
import { PodSignature } from '../../shared'

async function checkSignature (req: express.Request, res: express.Response, next: express.NextFunction) {
  const signatureObject: PodSignature = req.body.signature
  const host = signatureObject.host

  try {
    const pod = await db.Pod.loadByHost(host)
    if (pod === null) {
      logger.error('Unknown pod %s.', host)
      return res.sendStatus(403)
    }

    logger.debug('Checking signature from %s.', host)

    let signatureShouldBe
    // If there is data in the body the sender used it for its signature
    // If there is no data we just use its host as signature
    if (req.body.data) {
      signatureShouldBe = req.body.data
    } else {
      signatureShouldBe = host
    }

    const signatureOk = peertubeCryptoCheckSignature(pod.publicKey, signatureShouldBe, signatureObject.signature)

    if (signatureOk === true) {
      res.locals.secure = {
        pod
      }

      return next()
    }

    logger.error('Signature is not okay in body for %s.', signatureObject.host)
    return res.sendStatus(403)
  } catch (err) {
    logger.error('Cannot get signed host in body.', { error: err.stack, signature: signatureObject.signature })
    return res.sendStatus(500)
  }
}

// ---------------------------------------------------------------------------

export {
  checkSignature
}