server/helpers/peertube-crypto.ts

   1 import { Request } from 'express'
   2 import { BCRYPT_SALT_SIZE, HTTP_SIGNATURE, PRIVATE_RSA_KEY_SIZE } from '../initializers/constants'
   3 import { ActorModel } from '../models/activitypub/actor'
   4 import { createPrivateKey, getPublicKey, promisify1, promisify2, sha256 } from './core-utils'
   5 import { jsig, jsonld } from './custom-jsonld-signature'
   6 import { logger } from './logger'
   7 import { cloneDeep } from 'lodash'
   8 import { createVerify } from 'crypto'
   9 import { buildDigest } from '../lib/job-queue/handlers/utils/activitypub-http-utils'
  10 import * as bcrypt from 'bcrypt'
  11
  12 const bcryptComparePromise = promisify2<any, string, boolean>(bcrypt.compare)
  13 const bcryptGenSaltPromise = promisify1<number, string>(bcrypt.genSalt)
  14 const bcryptHashPromise = promisify2<any, string | number, string>(bcrypt.hash)
  15
  16 const httpSignature = require('http-signature')
  17
  18 async function createPrivateAndPublicKeys () {
  19   logger.info('Generating a RSA key...')
  20
  21   const { key } = await createPrivateKey(PRIVATE_RSA_KEY_SIZE)
  22   const { publicKey } = await getPublicKey(key)
  23
  24   return { privateKey: key, publicKey }
  25 }
  26
  27 // User password checks
  28
  29 function comparePassword (plainPassword: string, hashPassword: string) {
  30   return bcryptComparePromise(plainPassword, hashPassword)
  31 }
  32
  33 async function cryptPassword (password: string) {
  34   const salt = await bcryptGenSaltPromise(BCRYPT_SALT_SIZE)
  35
  36   return bcryptHashPromise(password, salt)
  37 }
  38
  39 // HTTP Signature
  40
  41 function isHTTPSignatureDigestValid (rawBody: Buffer, req: Request): boolean {
  42   if (req.headers[HTTP_SIGNATURE.HEADER_NAME] && req.headers['digest']) {
  43     return buildDigest(rawBody.toString()) === req.headers['digest']
  44   }
  45
  46   return true
  47 }
  48
  49 function isHTTPSignatureVerified (httpSignatureParsed: any, actor: ActorModel): boolean {
  50   return httpSignature.verifySignature(httpSignatureParsed, actor.publicKey) === true
  51 }
  52
  53 function parseHTTPSignature (req: Request, clockSkew?: number) {
  54   return httpSignature.parse(req, { authorizationHeaderName: HTTP_SIGNATURE.HEADER_NAME, clockSkew })
  55 }
  56
  57 // JSONLD
  58
  59 async function isJsonLDSignatureVerified (fromActor: ActorModel, signedDocument: any): Promise<boolean> {
  60   if (signedDocument.signature.type === 'RsaSignature2017') {
  61     // Mastodon algorithm
  62     const res = await isJsonLDRSA2017Verified(fromActor, signedDocument)
  63     // Success? If no, try with our library
  64     if (res === true) return true
  65   }
  66
  67   const publicKeyObject = {
  68     '@context': jsig.SECURITY_CONTEXT_URL,
  69     id: fromActor.url,
  70     type: 'CryptographicKey',
  71     owner: fromActor.url,
  72     publicKeyPem: fromActor.publicKey
  73   }
  74
  75   const publicKeyOwnerObject = {
  76     '@context': jsig.SECURITY_CONTEXT_URL,
  77     id: fromActor.url,
  78     publicKey: [ publicKeyObject ]
  79   }
  80
  81   const options = {
  82     publicKey: publicKeyObject,
  83     publicKeyOwner: publicKeyOwnerObject
  84   }
  85
  86   return jsig.promises
  87              .verify(signedDocument, options)
  88              .then((result: { verified: boolean }) => result.verified)
  89              .catch(err => {
  90                logger.error('Cannot check signature.', { err })
  91                return false
  92              })
  93 }
  94
  95 // Backward compatibility with "other" implementations
  96 async function isJsonLDRSA2017Verified (fromActor: ActorModel, signedDocument: any) {
  97   function hash (obj: any): Promise<any> {
  98     return jsonld.promises
  99                  .normalize(obj, {
 100                    algorithm: 'URDNA2015',
 101                    format: 'application/n-quads'
 102                  })
 103                  .then(res => sha256(res))
 104   }
 105
 106   const signatureCopy = cloneDeep(signedDocument.signature)
 107   Object.assign(signatureCopy, {
 108     '@context': [
 109       'https://w3id.org/security/v1',
 110       { RsaSignature2017: 'https://w3id.org/security#RsaSignature2017' }
 111     ]
 112   })
 113   delete signatureCopy.type
 114   delete signatureCopy.id
 115   delete signatureCopy.signatureValue
 116
 117   const docWithoutSignature = cloneDeep(signedDocument)
 118   delete docWithoutSignature.signature
 119
 120   const [ documentHash, optionsHash ] = await Promise.all([
 121     hash(docWithoutSignature),
 122     hash(signatureCopy)
 123   ])
 124
 125   const toVerify = optionsHash + documentHash
 126
 127   const verify = createVerify('RSA-SHA256')
 128   verify.update(toVerify, 'utf8')
 129
 130   return verify.verify(fromActor.publicKey, signedDocument.signature.signatureValue, 'base64')
 131 }
 132
 133 function signJsonLDObject (byActor: ActorModel, data: any) {
 134   const options = {
 135     privateKeyPem: byActor.privateKey,
 136     creator: byActor.url,
 137     algorithm: 'RsaSignature2017'
 138   }
 139
 140   return jsig.promises.sign(data, options)
 141 }
 142
 143 // ---------------------------------------------------------------------------
 144
 145 export {
 146   isHTTPSignatureDigestValid,
 147   parseHTTPSignature,
 148   isHTTPSignatureVerified,
 149   isJsonLDSignatureVerified,
 150   comparePassword,
 151   createPrivateAndPublicKeys,
 152   cryptPassword,
 153   signJsonLDObject
 154 }
 155
 156 // ---------------------------------------------------------------------------