@ -1,4 +1,69 @@
/* global dcodeIO, Internal, libsignal, sodium */
import ByteBuffer from 'bytebuffer' ;
import { generateKeyPair , sharedKey , verify } from 'curve25519-js' ;
import { default as sodiumWrappers } from 'libsodium-wrappers-sumo' ;
async function getSodium() {
await sodiumWrappers . ready ;
return sodiumWrappers ;
}
export async function decryptAttachmentBuffer ( encryptingKey : Uint8Array , bufferIn : ArrayBuffer ) {
const sodium = await getSodium ( ) ;
const header = new Uint8Array (
bufferIn . slice ( 0 , sodium . crypto_secretstream_xchacha20poly1305_HEADERBYTES )
) ;
const encryptedBuffer = new Uint8Array (
bufferIn . slice ( sodium . crypto_secretstream_xchacha20poly1305_HEADERBYTES )
) ;
try {
/* Decrypt the stream: initializes the state, using the key and a header */
const state = sodium . crypto_secretstream_xchacha20poly1305_init_pull ( header , encryptingKey ) ;
// what if ^ this call fail (? try to load as a unencrypted attachment?)
const messageTag = sodium . crypto_secretstream_xchacha20poly1305_pull ( state , encryptedBuffer ) ;
// we expect the final tag to be there. If not, we might have an issue with this file
// maybe not encrypted locally?
if ( messageTag . tag === sodium . crypto_secretstream_xchacha20poly1305_TAG_FINAL ) {
return messageTag . message ;
}
} catch ( e ) {
// tslint:disable: no-console
console . error ( 'Failed to load the file as an encrypted one' , e ) ;
}
return new Uint8Array ( ) ;
}
export async function encryptAttachmentBuffer ( encryptingKey : Uint8Array , bufferIn : ArrayBuffer ) {
const sodium = await getSodium ( ) ;
try {
const uintArrayIn = new Uint8Array ( bufferIn ) ;
/* Set up a new stream: initialize the state and create the header */
const { state , header } = sodium . crypto_secretstream_xchacha20poly1305_init_push ( encryptingKey ) ;
/* Now, encrypt the buffer. */
const bufferOut = sodium . crypto_secretstream_xchacha20poly1305_push (
state ,
uintArrayIn ,
null ,
sodium . crypto_secretstream_xchacha20poly1305_TAG_FINAL
) ;
const encryptedBufferWithHeader = new Uint8Array ( bufferOut . length + header . length ) ;
encryptedBufferWithHeader . set ( header ) ;
encryptedBufferWithHeader . set ( bufferOut , header . length ) ;
return { encryptedBufferWithHeader , header } ;
} catch ( e ) {
console . error ( 'encryptAttachmentBuffer error: ' , e ) ;
return null ;
}
}
/* global dcodeIO, Internal, libsignal */
/* eslint-disable no-console */
/* eslint-disable strict */
@ -10,17 +75,17 @@ const functions = {
DecryptAESGCM ,
deriveSymmetricKey ,
encryptForPubkey ,
generateEphemeralKeyPair ,
decryptAttachmentBuffer ,
encryptAttachmentBuffer ,
bytesFromString ,
} ;
// tslint:disable: function-name
onmessage = async e = > {
const [ jobId , fnName , . . . args ] = e . data ;
try {
const fn = functions [ fnName ] ;
const fn = ( functions as any ) [ fnName ] ;
if ( ! fn ) {
throw new Error ( ` Worker: job ${ jobId } did not find function ${ fnName } ` ) ;
}
@ -32,7 +97,7 @@ onmessage = async e => {
}
} ;
function prepareErrorForPostMessage ( error ) {
function prepareErrorForPostMessage ( error : any ) {
if ( ! error ) {
return null ;
}
@ -44,28 +109,32 @@ function prepareErrorForPostMessage(error) {
return error . message ;
}
function arrayBufferToStringBase64 ( arrayBuffer ) {
return dcodeIO. ByteBuffer. wrap ( arrayBuffer ) . toString ( 'base64' ) ;
function arrayBufferToStringBase64 ( arrayBuffer : ArrayBuffer ) {
return . wrap ( arrayBuffer ) . toString ( 'base64' ) ;
}
function fromBase64ToArrayBuffer ( base64Str ) {
return dcodeIO. ByteBuffer. wrap ( base64Str , 'base64' ) . toArrayBuffer ( ) ;
function fromBase64ToArrayBuffer ( base64Str : string ) {
return . wrap ( base64Str , 'base64' ) . toArrayBuffer ( ) ;
}
function fromHexToArray ( hexStr ) {
return new Uint8Array ( dcodeIO. ByteBuffer. wrap ( hexStr , 'hex' ) . toArrayBuffer ( ) ) ;
function fromHexToArray ( hexStr : string ) {
return new Uint8Array ( . wrap ( hexStr , 'hex' ) . toArrayBuffer ( ) ) ;
}
function fromHexToArrayBuffer ( hexStr ) {
return dcodeIO. ByteBuffer. wrap ( hexStr , 'hex' ) . toArrayBuffer ( ) ;
function fromHexToArrayBuffer ( hexStr : string ) {
return . wrap ( hexStr , 'hex' ) . toArrayBuffer ( ) ;
}
function bytesFromString ( string ) {
return dcodeIO. ByteBuffer . wrap ( string , 'utf8' ) . toArrayBuffer ( ) ;
function bytesFromString ( str : string ) {
return ByteBuffer. wrap ( str , 'utf8' ) . toArrayBuffer ( ) ;
}
// hexString, base64String, base64String
async function verifySignature ( senderPubKey , messageBase64 , signatureBase64 ) {
async function verifySignature (
senderPubKey : string ,
messageBase64 : string ,
signatureBase64 : string
) {
try {
if ( typeof senderPubKey !== 'string' ) {
throw new Error ( 'senderPubKey type not correct' ) ;
@ -78,14 +147,11 @@ async function verifySignature(senderPubKey, messageBase64, signatureBase64) {
}
const messageData = new Uint8Array ( fromBase64ToArrayBuffer ( messageBase64 ) ) ;
const signature = new Uint8Array ( fromBase64ToArrayBuffer ( signatureBase64 ) ) ;
// verify returns true if the signature is not correct
const verifyRet = Internal . curve25519 . verify (
fromHexToArray ( senderPubKey ) ,
messageData ,
signature
) ;
if ( verifyRet ) {
const verifyRet = verify ( fromHexToArray ( senderPubKey ) , messageData , signature ) ;
if ( ! verifyRet ) {
console . error ( 'Invalid signature' ) ;
return false ;
}
@ -99,14 +165,10 @@ async function verifySignature(senderPubKey, messageBase64, signatureBase64) {
const NONCE_LENGTH = 12 ;
// uint8array, uint8array
async function deriveSymmetricKey ( x25519PublicKey , x25519PrivateKey ) {
async function deriveSymmetricKey ( x25519PublicKey : Uint8Array , x25519PrivateKey : Uint8Array ) {
assertArrayBufferView ( x25519PublicKey ) ;
assertArrayBufferView ( x25519PrivateKey ) ;
const ephemeralSecret = await libsignal . Curve . async . calculateAgreement (
x25519PublicKey . buffer ,
x25519PrivateKey . buffer
) ;
const ephemeralSecret = sharedKey ( x25519PrivateKey , x25519PublicKey ) ;
const salt = bytesFromString ( 'LOKI' ) ;
@ -127,20 +189,22 @@ async function deriveSymmetricKey(x25519PublicKey, x25519PrivateKey) {
}
async function generateEphemeralKeyPair() {
const keys = await libsignal . Curve . async . generateKeyPair ( ) ;
// Signal protocol prepends with "0x05"
keys . pubKey = keys . pubKey . slice ( 1 ) ;
const ran = ( await getSodium ( ) ) . randombytes_buf ( 32 ) ;
const keys = generateKeyPair ( ran ) ;
return keys ;
// Signal protocol prepends with "0x05"
// keys.pubKey = keys.pubKey.slice(1);
// return { pubKey: keys.public, privKey: keys.private };
}
function assertArrayBufferView ( val ) {
function assertArrayBufferView ( val : any ) {
if ( ! ArrayBuffer . isView ( val ) ) {
throw new Error ( 'val type not correct' ) ;
}
}
// encryptForPubkey: hexString, payloadBytes: Uint8Array
async function encryptForPubkey ( pubkeyX25519str , payloadBytes ) {
async function encryptForPubkey ( pubkeyX25519str : string , payloadBytes : Uint8Array ) {
try {
if ( typeof pubkeyX25519str !== 'string' ) {
throw new Error ( 'pubkeyX25519str type not correct' ) ;
@ -150,18 +214,18 @@ async function encryptForPubkey(pubkeyX25519str, payloadBytes) {
const pubkeyX25519Buffer = fromHexToArray ( pubkeyX25519str ) ;
const symmetricKey = await deriveSymmetricKey (
pubkeyX25519Buffer ,
new Uint8Array ( ephemeral . privKey )
new Uint8Array ( ephemeral . private )
) ;
const ciphertext = await EncryptAESGCM ( symmetricKey , payloadBytes ) ;
return { ciphertext , symmetricKey , ephemeralKey : ephemeral.pub Key } ;
return { ciphertext , symmetricKey , ephemeralKey : ephemeral.pub lic } ;
} catch ( e ) {
console . error ( 'encryptForPubkey got an error:' , e ) ;
return null ;
}
}
async function EncryptAESGCM ( symmetricKey , plaintext ) {
async function EncryptAESGCM ( symmetricKey : ArrayBuffer , plaintext : ArrayBuffer ) {
const nonce = crypto . getRandomValues ( new Uint8Array ( NONCE_LENGTH ) ) ;
const key = await crypto . subtle . importKey ( 'raw' , symmetricKey , { name : 'AES-GCM' } , false , [
@ -174,6 +238,7 @@ async function EncryptAESGCM(symmetricKey, plaintext) {
plaintext
) ;
// tslint:disable-next-line: restrict-plus-operands
const ivAndCiphertext = new Uint8Array ( NONCE_LENGTH + ciphertext . byteLength ) ;
ivAndCiphertext . set ( nonce ) ;
@ -183,7 +248,7 @@ async function EncryptAESGCM(symmetricKey, plaintext) {
}
// uint8array, uint8array
async function DecryptAESGCM ( symmetricKey , ivAndCiphertext ) {
async function DecryptAESGCM ( symmetricKey : Uint8Array , ivAndCiphertext : Uint8Array ) {
assertArrayBufferView ( symmetricKey ) ;
assertArrayBufferView ( ivAndCiphertext ) ;
@ -200,65 +265,3 @@ async function DecryptAESGCM(symmetricKey, ivAndCiphertext) {
return crypto . subtle . decrypt ( { name : 'AES-GCM' , iv : nonce } , key , ciphertext ) ;
}
async function getSodium() {
await sodium . ready ;
return sodium ;
}
// Uint8Array, ArrayBuffer
async function decryptAttachmentBuffer ( encryptingKey , bufferIn ) {
const sodium = await getSodium ( ) ;
const header = new Uint8Array (
bufferIn . slice ( 0 , sodium . crypto_secretstream_xchacha20poly1305_HEADERBYTES )
) ;
const encryptedBuffer = new Uint8Array (
bufferIn . slice ( sodium . crypto_secretstream_xchacha20poly1305_HEADERBYTES )
) ;
try {
/* Decrypt the stream: initializes the state, using the key and a header */
const state = sodium . crypto_secretstream_xchacha20poly1305_init_pull ( header , encryptingKey ) ;
// what if ^ this call fail (? try to load as a unencrypted attachment?)
const messageTag = sodium . crypto_secretstream_xchacha20poly1305_pull ( state , encryptedBuffer ) ;
// we expect the final tag to be there. If not, we might have an issue with this file
// maybe not encrypted locally?
if ( messageTag . tag === sodium . crypto_secretstream_xchacha20poly1305_TAG_FINAL ) {
return messageTag . message ;
}
} catch ( e ) {
console . error ( 'Failed to load the file as an encrypted one' , e ) ;
}
return new Uint8Array ( ) ;
}
// Uint8Array, ArrayBuffer
async function encryptAttachmentBuffer ( encryptingKey , bufferIn ) {
const sodium = await getSodium ( ) ;
try {
const uintArrayIn = new Uint8Array ( bufferIn ) ;
/* Set up a new stream: initialize the state and create the header */
const { state , header } = sodium . crypto_secretstream_xchacha20poly1305_init_push ( encryptingKey ) ;
/* Now, encrypt the buffer. */
const bufferOut = sodium . crypto_secretstream_xchacha20poly1305_push (
state ,
uintArrayIn ,
null ,
sodium . crypto_secretstream_xchacha20poly1305_TAG_FINAL
) ;
const encryptedBufferWithHeader = new Uint8Array ( bufferOut . length + header . length ) ;
encryptedBufferWithHeader . set ( header ) ;
encryptedBufferWithHeader . set ( bufferOut , header . length ) ;
return { encryptedBufferWithHeader , header } ;
} catch ( e ) {
console . error ( 'encryptAttachmentBuffer error: ' , e ) ;
return null ;
}
}
Audric Ackermann
3 years ago