Improve error logging/reporting in megolm import/export

I saw a rageshake where somebody had apparently failed to import a key file.
I have no idea why it happened.

Also try to make the errors the users see useful.
This commit is contained in:
Richard van der Hoff 2017-06-08 14:21:25 +01:00
parent b16e652acc
commit 175599beda
4 changed files with 129 additions and 56 deletions

View file

@ -81,11 +81,13 @@ export default React.createClass({
FileSaver.saveAs(blob, 'riot-keys.txt');
this.props.onFinished(true);
}).catch((e) => {
console.error("Error exporting e2e keys:", e);
if (this._unmounted) {
return;
}
const msg = e.friendlyText || _t('Unknown error');
this.setState({
errStr: e.message,
errStr: msg,
phase: PHASE_EDIT,
});
});

View file

@ -89,11 +89,13 @@ export default React.createClass({
// TODO: it would probably be nice to give some feedback about what we've imported here.
this.props.onFinished(true);
}).catch((e) => {
console.error("Error importing e2e keys:", e);
if (this._unmounted) {
return;
}
const msg = e.friendlyText || _t('Unknown error');
this.setState({
errStr: e.message,
errStr: msg,
phase: PHASE_EDIT,
});
});

View file

@ -860,5 +860,8 @@
"Username not available": "Username not available",
"Something went wrong!": "Something went wrong!",
"This will be your account name on the <span></span> homeserver, or you can pick a <a>different server</a>.": "This will be your account name on the <span></span> homeserver, or you can pick a <a>different server</a>.",
"If you already have a Matrix account you can <a>log in</a> instead.": "If you already have a Matrix account you can <a>log in</a> instead."
"If you already have a Matrix account you can <a>log in</a> instead.": "If you already have a Matrix account you can <a>log in</a> instead.",
"Your browser does not support the required cryptography extensions": "Your browser does not support the required cryptography extensions",
"Not a valid Riot keyfile": "Not a valid Riot keyfile",
"Authentication check failed: incorrect password?": "Authentication check failed: incorrect password?"
}

View file

@ -27,31 +27,57 @@ if (!TextDecoder) {
TextDecoder = TextEncodingUtf8.TextDecoder;
}
import { _t } from '../languageHandler';
const subtleCrypto = window.crypto.subtle || window.crypto.webkitSubtle;
/**
* Make an Error object which has a friendlyText property which is already
* translated and suitable for showing to the user.
*
* @param {string} msg message for the exception
* @param {string} friendlyText
* @returns {Error}
*/
function friendlyError(msg, friendlyText) {
const e = new Error(msg);
e.friendlyText = friendlyText;
return e;
}
function cryptoFailMsg() {
return _t('Your browser does not support the required cryptography extensions');
}
/**
* Decrypt a megolm key file
*
* @param {ArrayBuffer} data file to decrypt
* @param {String} password
* @return {Promise<String>} promise for decrypted output
*
*
*/
export async function decryptMegolmKeyFile(data, password) {
const body = unpackMegolmKeyFile(data);
// check we have a version byte
if (body.length < 1) {
throw new Error('Invalid file: too short');
throw friendlyError('Invalid file: too short',
_t('Not a valid Riot keyfile'));
}
const version = body[0];
if (version !== 1) {
throw new Error('Unsupported version');
throw friendlyError('Unsupported version',
_t('Not a valid Riot keyfile'));
}
const ciphertextLength = body.length-(1+16+16+4+32);
if (ciphertextLength < 0) {
throw new Error('Invalid file: too short');
throw friendlyError('Invalid file: too short',
_t('Not a valid Riot keyfile'));
}
const salt = body.subarray(1, 1+16);
@ -61,19 +87,27 @@ export async function decryptMegolmKeyFile(data, password) {
const hmac = body.subarray(-32);
const [aesKey, hmacKey] = await deriveKeys(salt, iterations, password);
const toVerify = body.subarray(0, -32);
const isValid = await subtleCrypto.verify(
let isValid;
try {
isValid = await subtleCrypto.verify(
{name: 'HMAC'},
hmacKey,
hmac,
toVerify,
);
} catch (e) {
throw friendlyError('subtleCrypto.verify failed: ' + e, cryptoFailMsg());
}
if (!isValid) {
throw new Error('Authentication check failed: incorrect password?');
throw friendlyError('hmac mismatch',
_t('Authentication check failed: incorrect password?'));
}
const plaintext = await subtleCrypto.decrypt(
let plaintext;
try {
plaintext = await subtleCrypto.decrypt(
{
name: "AES-CTR",
counter: iv,
@ -82,6 +116,9 @@ export async function decryptMegolmKeyFile(data, password) {
aesKey,
ciphertext,
);
} catch(e) {
throw friendlyError('subtleCrypto.decrypt failed: ' + e, cryptoFailMsg());
}
return new TextDecoder().decode(new Uint8Array(plaintext));
}
@ -113,16 +150,22 @@ export async function encryptMegolmKeyFile(data, password, options) {
iv[9] &= 0x7f;
const [aesKey, hmacKey] = await deriveKeys(salt, kdfRounds, password);
const encodedData = new TextEncoder().encode(data);
const ciphertext = await subtleCrypto.encrypt(
let ciphertext;
try {
ciphertext = await subtleCrypto.encrypt(
{
name: "AES-CTR",
counter: iv,
length: 64,
},
aesKey,
new TextEncoder().encode(data),
encodedData,
);
} catch (e) {
throw friendlyError('subtleCrypto.encrypt failed: ' + e, cryptoFailMsg());
}
const cipherArray = new Uint8Array(ciphertext);
const bodyLength = (1+salt.length+iv.length+4+cipherArray.length+32);
@ -139,11 +182,17 @@ export async function encryptMegolmKeyFile(data, password, options) {
const toSign = resultBuffer.subarray(0, idx);
const hmac = await subtleCrypto.sign(
let hmac;
try {
hmac = await subtleCrypto.sign(
{name: 'HMAC'},
hmacKey,
toSign,
);
} catch (e) {
throw friendlyError('subtleCrypto.sign failed: ' + e, cryptoFailMsg());
}
const hmacArray = new Uint8Array(hmac);
resultBuffer.set(hmacArray, idx);
@ -160,15 +209,23 @@ export async function encryptMegolmKeyFile(data, password, options) {
*/
async function deriveKeys(salt, iterations, password) {
const start = new Date();
const key = await subtleCrypto.importKey(
let key;
try {
key = await subtleCrypto.importKey(
'raw',
new TextEncoder().encode(password),
{name: 'PBKDF2'},
false,
['deriveBits'],
);
} catch (e) {
throw friendlyError('subtleCrypto.importKey failed: ' + e, cryptoFailMsg());
}
const keybits = await subtleCrypto.deriveBits(
let keybits;
try {
keybits = await subtleCrypto.deriveBits(
{
name: 'PBKDF2',
salt: salt,
@ -178,6 +235,9 @@ async function deriveKeys(salt, iterations, password) {
key,
512,
);
} catch (e) {
throw friendlyError('subtleCrypto.deriveBits failed: ' + e, cryptoFailMsg());
}
const now = new Date();
console.log("E2e import/export: deriveKeys took " + (now - start) + "ms");
@ -191,7 +251,10 @@ async function deriveKeys(salt, iterations, password) {
{name: 'AES-CTR'},
false,
['encrypt', 'decrypt'],
);
).catch((e) => {
throw friendlyError('subtleCrypto.importKey failed for AES key: ' + e, cryptoFailMsg());
});
const hmacProm = subtleCrypto.importKey(
'raw',
hmacKey,
@ -201,7 +264,10 @@ async function deriveKeys(salt, iterations, password) {
},
false,
['sign', 'verify'],
);
).catch((e) => {
throw friendlyError('subtleCrypto.importKey failed for HMAC key: ' + e, cryptoFailMsg());
});
return await Promise.all([aesProm, hmacProm]);
}