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 import { MActor } from '../typings/models'
  12
  13 const bcryptComparePromise = promisify2<any, string, boolean>(bcrypt.compare)
  14 const bcryptGenSaltPromise = promisify1<number, string>(bcrypt.genSalt)
  15 const bcryptHashPromise = promisify2<any, string | number, string>(bcrypt.hash)
  16
  17 const httpSignature = require('http-signature')
  18
  19 async function createPrivateAndPublicKeys () {
  20   logger.info('Generating a RSA key...')
  21
  22   const { key } = await createPrivateKey(PRIVATE_RSA_KEY_SIZE)
  23   const { publicKey } = await getPublicKey(key)
  24
  25   return { privateKey: key, publicKey }
  26 }
  27
  28 // User password checks
  29
  30 function comparePassword (plainPassword: string, hashPassword: string) {
  31   return bcryptComparePromise(plainPassword, hashPassword)
  32 }
  33
  34 async function cryptPassword (password: string) {
  35   const salt = await bcryptGenSaltPromise(BCRYPT_SALT_SIZE)
  36
  37   return bcryptHashPromise(password, salt)
  38 }
  39
  40 // HTTP Signature
  41
  42 function isHTTPSignatureDigestValid (rawBody: Buffer, req: Request): boolean {
  43   if (req.headers[HTTP_SIGNATURE.HEADER_NAME] && req.headers['digest']) {
  44     return buildDigest(rawBody.toString()) === req.headers['digest']
  45   }
  46
  47   return true
  48 }
  49
  50 function isHTTPSignatureVerified (httpSignatureParsed: any, actor: MActor): boolean {
  51   return httpSignature.verifySignature(httpSignatureParsed, actor.publicKey) === true
  52 }
  53
  54 function parseHTTPSignature (req: Request, clockSkew?: number) {
  55   return httpSignature.parse(req, { authorizationHeaderName: HTTP_SIGNATURE.HEADER_NAME, clockSkew })
  56 }
  57
  58 // JSONLD
  59
  60 async function isJsonLDSignatureVerified (fromActor: MActor, signedDocument: any): Promise<boolean> {
  61   if (signedDocument.signature.type === 'RsaSignature2017') {
  62     // Mastodon algorithm
  63     const res = await isJsonLDRSA2017Verified(fromActor, signedDocument)
  64     // Success? If no, try with our library
  65     if (res === true) return true
  66   }
  67
  68   const publicKeyObject = {
  69     '@context': jsig.SECURITY_CONTEXT_URL,
  70     id: fromActor.url,
  71     type: 'CryptographicKey',
  72     owner: fromActor.url,
  73     publicKeyPem: fromActor.publicKey
  74   }
  75
  76   const publicKeyOwnerObject = {
  77     '@context': jsig.SECURITY_CONTEXT_URL,
  78     id: fromActor.url,
  79     publicKey: [ publicKeyObject ]
  80   }
  81
  82   const options = {
  83     publicKey: publicKeyObject,
  84     publicKeyOwner: publicKeyOwnerObject
  85   }
  86
  87   return jsig.promises
  88              .verify(signedDocument, options)
  89              .then((result: { verified: boolean }) => result.verified)
  90              .catch(err => {
  91                logger.error('Cannot check signature.', { err })
  92                return false
  93              })
  94 }
  95
  96 // Backward compatibility with "other" implementations
  97 async function isJsonLDRSA2017Verified (fromActor: MActor, signedDocument: any) {
  98   function hash (obj: any): Promise<any> {
  99     return jsonld.promises
 100                  .normalize(obj, {
 101                    algorithm: 'URDNA2015',
 102                    format: 'application/n-quads'
 103                  })
 104                  .then(res => sha256(res))
 105   }
 106
 107   const signatureCopy = cloneDeep(signedDocument.signature)
 108   Object.assign(signatureCopy, {
 109     '@context': [
 110       'https://w3id.org/security/v1',
 111       { RsaSignature2017: 'https://w3id.org/security#RsaSignature2017' }
 112     ]
 113   })
 114   delete signatureCopy.type
 115   delete signatureCopy.id
 116   delete signatureCopy.signatureValue
 117
 118   const docWithoutSignature = cloneDeep(signedDocument)
 119   delete docWithoutSignature.signature
 120
 121   const [ documentHash, optionsHash ] = await Promise.all([
 122     hash(docWithoutSignature),
 123     hash(signatureCopy)
 124   ])
 125
 126   const toVerify = optionsHash + documentHash
 127
 128   const verify = createVerify('RSA-SHA256')
 129   verify.update(toVerify, 'utf8')
 130
 131   return verify.verify(fromActor.publicKey, signedDocument.signature.signatureValue, 'base64')
 132 }
 133
 134 function signJsonLDObject (byActor: MActor, data: any) {
 135   const options = {
 136     privateKeyPem: byActor.privateKey,
 137     creator: byActor.url,
 138     algorithm: 'RsaSignature2017'
 139   }
 140
 141   return jsig.promises.sign(data, options)
 142 }
 143
 144 // ---------------------------------------------------------------------------
 145
 146 export {
 147   isHTTPSignatureDigestValid,
 148   parseHTTPSignature,
 149   isHTTPSignatureVerified,
 150   isJsonLDSignatureVerified,
 151   comparePassword,
 152   createPrivateAndPublicKeys,
 153   cryptPassword,
 154   signJsonLDObject
 155 }
 156
 157 // ---------------------------------------------------------------------------