bitwarden-estensione-browser/src/services/webCryptoFunction.service.ts

282 lines
11 KiB
TypeScript

import * as forge from 'node-forge';
import { CryptoFunctionService } from '../abstractions/cryptoFunction.service';
import { PlatformUtilsService } from '../abstractions/platformUtils.service';
import { Utils } from '../misc/utils';
import { SymmetricCryptoKey } from '../models/domain';
import { DecryptParameters } from '../models/domain/decryptParameters';
export class WebCryptoFunctionService implements CryptoFunctionService {
private crypto: Crypto;
private subtle: SubtleCrypto;
private isEdge: boolean;
private isIE: boolean;
constructor(private win: Window, private platformUtilsService: PlatformUtilsService) {
this.crypto = typeof win.crypto !== 'undefined' ? win.crypto : null;
this.subtle = (!!this.crypto && typeof win.crypto.subtle !== 'undefined') ? win.crypto.subtle : null;
this.isEdge = platformUtilsService.isEdge();
this.isIE = platformUtilsService.isIE();
}
async pbkdf2(password: string | ArrayBuffer, salt: string | ArrayBuffer, algorithm: 'sha256' | 'sha512',
iterations: number): Promise<ArrayBuffer> {
if (this.isEdge || this.isIE) {
const forgeLen = algorithm === 'sha256' ? 32 : 64;
const passwordBytes = this.toByteString(password);
const saltBytes = this.toByteString(salt);
const derivedKeyBytes = (forge as any).pbkdf2(passwordBytes, saltBytes, iterations, forgeLen, algorithm);
return Utils.fromByteStringToArray(derivedKeyBytes).buffer;
}
const wcLen = algorithm === 'sha256' ? 256 : 512;
const passwordBuf = this.toBuf(password);
const saltBuf = this.toBuf(salt);
const pbkdf2Params: Pbkdf2Params = {
name: 'PBKDF2',
salt: saltBuf,
iterations: iterations,
hash: { name: this.toWebCryptoAlgorithm(algorithm) },
};
const impKey = await this.subtle.importKey('raw', passwordBuf, { name: 'PBKDF2' } as any,
false, ['deriveBits']);
return await this.subtle.deriveBits(pbkdf2Params, impKey, wcLen);
}
async hash(value: string | ArrayBuffer, algorithm: 'sha1' | 'sha256' | 'sha512' | 'md5'): Promise<ArrayBuffer> {
if (((this.isEdge || this.isIE) && algorithm === 'sha1') || algorithm === 'md5') {
const md = algorithm === 'md5' ? forge.md.md5.create() : forge.md.sha1.create();
const valueBytes = this.toByteString(value);
md.update(valueBytes, 'raw');
return Utils.fromByteStringToArray(md.digest().data).buffer;
}
const valueBuf = this.toBuf(value);
return await this.subtle.digest({ name: this.toWebCryptoAlgorithm(algorithm) }, valueBuf);
}
async hmac(value: ArrayBuffer, key: ArrayBuffer, algorithm: 'sha1' | 'sha256' | 'sha512'): Promise<ArrayBuffer> {
if (this.isIE && algorithm === 'sha512') {
const hmac = (forge as any).hmac.create();
const keyBytes = this.toByteString(key);
const valueBytes = this.toByteString(value);
hmac.start(algorithm, keyBytes);
hmac.update(valueBytes, 'raw');
return Utils.fromByteStringToArray(hmac.digest().data).buffer;
}
const signingAlgorithm = {
name: 'HMAC',
hash: { name: this.toWebCryptoAlgorithm(algorithm) },
};
const impKey = await this.subtle.importKey('raw', key, signingAlgorithm, false, ['sign']);
return await this.subtle.sign(signingAlgorithm, impKey, value);
}
// Safely compare two values in a way that protects against timing attacks (Double HMAC Verification).
// ref: https://www.nccgroup.trust/us/about-us/newsroom-and-events/blog/2011/february/double-hmac-verification/
// ref: https://paragonie.com/blog/2015/11/preventing-timing-attacks-on-string-comparison-with-double-hmac-strategy
async compare(a: ArrayBuffer, b: ArrayBuffer): Promise<boolean> {
const macKey = await this.randomBytes(32);
const signingAlgorithm = {
name: 'HMAC',
hash: { name: 'SHA-256' },
};
const impKey = await this.subtle.importKey('raw', macKey, signingAlgorithm, false, ['sign']);
const mac1 = await this.subtle.sign(signingAlgorithm, impKey, a);
const mac2 = await this.subtle.sign(signingAlgorithm, impKey, b);
if (mac1.byteLength !== mac2.byteLength) {
return false;
}
const arr1 = new Uint8Array(mac1);
const arr2 = new Uint8Array(mac2);
for (let i = 0; i < arr2.length; i++) {
if (arr1[i] !== arr2[i]) {
return false;
}
}
return true;
}
hmacFast(value: string, key: string, algorithm: 'sha1' | 'sha256' | 'sha512'): Promise<string> {
const hmac = (forge as any).hmac.create();
hmac.start(algorithm, key);
hmac.update(value);
const bytes = hmac.digest().getBytes();
return Promise.resolve(bytes);
}
async compareFast(a: string, b: string): Promise<boolean> {
const rand = await this.randomBytes(32);
const bytes = new Uint32Array(rand);
const buffer = forge.util.createBuffer();
for (let i = 0; i < bytes.length; i++) {
buffer.putInt32(bytes[i]);
}
const macKey = buffer.getBytes();
const hmac = (forge as any).hmac.create();
hmac.start('sha256', macKey);
hmac.update(a);
const mac1 = hmac.digest().getBytes();
hmac.start(null, null);
hmac.update(b);
const mac2 = hmac.digest().getBytes();
const equals = mac1 === mac2;
return equals;
}
async aesEncrypt(data: ArrayBuffer, iv: ArrayBuffer, key: ArrayBuffer): Promise<ArrayBuffer> {
const impKey = await this.subtle.importKey('raw', key, { name: 'AES-CBC' } as any, false, ['encrypt']);
return await this.subtle.encrypt({ name: 'AES-CBC', iv: iv }, impKey, data);
}
aesDecryptFastParameters(data: string, iv: string, mac: string, key: SymmetricCryptoKey):
DecryptParameters<string> {
const p = new DecryptParameters<string>();
if (key.meta != null) {
p.encKey = key.meta.encKeyByteString;
p.macKey = key.meta.macKeyByteString;
}
if (p.encKey == null) {
p.encKey = forge.util.decode64(key.encKeyB64);
}
p.data = forge.util.decode64(data);
p.iv = forge.util.decode64(iv);
p.macData = p.iv + p.data;
if (p.macKey == null && key.macKeyB64 != null) {
p.macKey = forge.util.decode64(key.macKeyB64);
}
if (mac != null) {
p.mac = forge.util.decode64(mac);
}
// cache byte string keys for later
if (key.meta == null) {
key.meta = {};
}
if (key.meta.encKeyByteString == null) {
key.meta.encKeyByteString = p.encKey;
}
if (p.macKey != null && key.meta.macKeyByteString == null) {
key.meta.macKeyByteString = p.macKey;
}
return p;
}
aesDecryptFast(parameters: DecryptParameters<string>): Promise<string> {
const dataBuffer = (forge as any).util.createBuffer(parameters.data);
const decipher = (forge as any).cipher.createDecipher('AES-CBC', parameters.encKey);
decipher.start({ iv: parameters.iv });
decipher.update(dataBuffer);
decipher.finish();
const val = decipher.output.toString('utf8');
return Promise.resolve(val);
}
async aesDecrypt(data: ArrayBuffer, iv: ArrayBuffer, key: ArrayBuffer): Promise<ArrayBuffer> {
const impKey = await this.subtle.importKey('raw', key, { name: 'AES-CBC' } as any, false, ['decrypt']);
return await this.subtle.decrypt({ name: 'AES-CBC', iv: iv }, impKey, data);
}
async rsaEncrypt(data: ArrayBuffer, publicKey: ArrayBuffer, algorithm: 'sha1' | 'sha256'): Promise<ArrayBuffer> {
// Note: Edge browser requires that we specify name and hash for both key import and decrypt.
// We cannot use the proper types here.
const rsaParams = {
name: 'RSA-OAEP',
hash: { name: this.toWebCryptoAlgorithm(algorithm) },
};
const impKey = await this.subtle.importKey('spki', publicKey, rsaParams, false, ['encrypt']);
return await this.subtle.encrypt(rsaParams, impKey, data);
}
async rsaDecrypt(data: ArrayBuffer, privateKey: ArrayBuffer, algorithm: 'sha1' | 'sha256'): Promise<ArrayBuffer> {
// Note: Edge browser requires that we specify name and hash for both key import and decrypt.
// We cannot use the proper types here.
const rsaParams = {
name: 'RSA-OAEP',
hash: { name: this.toWebCryptoAlgorithm(algorithm) },
};
const impKey = await this.subtle.importKey('pkcs8', privateKey, rsaParams, false, ['decrypt']);
return await this.subtle.decrypt(rsaParams, impKey, data);
}
async rsaExtractPublicKey(privateKey: ArrayBuffer): Promise<ArrayBuffer> {
const rsaParams = {
name: 'RSA-OAEP',
// Have to specify some algorithm
hash: { name: this.toWebCryptoAlgorithm('sha1') },
};
const impPrivateKey = await this.subtle.importKey('pkcs8', privateKey, rsaParams, true, ['decrypt']);
const jwkPrivateKey = await this.subtle.exportKey('jwk', impPrivateKey);
const jwkPublicKeyParams = {
kty: 'RSA',
e: jwkPrivateKey.e,
n: jwkPrivateKey.n,
alg: 'RSA-OAEP',
ext: true,
};
const impPublicKey = await this.subtle.importKey('jwk', jwkPublicKeyParams, rsaParams, true, ['encrypt']);
return await this.subtle.exportKey('spki', impPublicKey);
}
async rsaGenerateKeyPair(length: 1024 | 2048 | 4096): Promise<[ArrayBuffer, ArrayBuffer]> {
const rsaParams = {
name: 'RSA-OAEP',
modulusLength: length,
publicExponent: new Uint8Array([0x01, 0x00, 0x01]), // 65537
// Have to specify some algorithm
hash: { name: this.toWebCryptoAlgorithm('sha1') },
};
const keyPair = await this.subtle.generateKey(rsaParams, true, ['encrypt', 'decrypt']);
const publicKey = await this.subtle.exportKey('spki', keyPair.publicKey);
const privateKey = await this.subtle.exportKey('pkcs8', keyPair.privateKey);
return [publicKey, privateKey];
}
randomBytes(length: number): Promise<ArrayBuffer> {
const arr = new Uint8Array(length);
this.crypto.getRandomValues(arr);
return Promise.resolve(arr.buffer);
}
private toBuf(value: string | ArrayBuffer): ArrayBuffer {
let buf: ArrayBuffer;
if (typeof (value) === 'string') {
buf = Utils.fromUtf8ToArray(value).buffer;
} else {
buf = value;
}
return buf;
}
private toByteString(value: string | ArrayBuffer): string {
let bytes: string;
if (typeof (value) === 'string') {
bytes = forge.util.encodeUtf8(value);
} else {
bytes = Utils.fromBufferToByteString(value);
}
return bytes;
}
private toWebCryptoAlgorithm(algorithm: 'sha1' | 'sha256' | 'sha512' | 'md5'): string {
if (algorithm === 'md5') {
throw new Error('MD5 is not supported in WebCrypto.');
}
return algorithm === 'sha1' ? 'SHA-1' : algorithm === 'sha256' ? 'SHA-256' : 'SHA-512';
}
}