geckon01/TwoFactorAuth
1
0
Fork 0
mirror of https://github.com/RobThree/TwoFactorAuth.git synced 2026-08-17 09:30:56 +00:00
Code Issues Packages Projects Releases Wiki Activity

remove insecure rng providers and remove polyfill for hash_equals (#122)

Browse Source 
* remove insecure rng providers

and remove the openssl provider. We now rely exclusively on
random_bytes(), as there are no reasons not to. Fix #121

* remove the isSecure property of the test rng class

* remove pointless test rng class

we were testing a test class, which didn't make a lot of sense.

* Revert "remove pointless test rng class"

This reverts commit f6da6bee6d.

* Reapply "remove pointless test rng class"

This reverts commit 06220d4a54.

* assing rng provider to class attribute

this also aligns with other providers

* remove polyfill for hash_equals
This commit is contained in:
Nicolas CARPi
2024-04-16 17:52:51 +02:00
committed by GitHub
parent 323053bd52
commit 194ecc28eb
12 changed files with 12 additions and 279 deletions
Download Patch File Download Diff File Expand all files Collapse all files
README.md
-1
View File
@@ -19,7 +19,6 @@ You can make use of the included [Endroid](https://robthree.github.io/TwoFactorA
* Requires PHP version >=8.1
* [cURL](http://php.net/manual/en/book.curl.php) when using the provided `QRServerProvider` (default), `ImageChartsQRCodeProvider` or `QRicketProvider` but you can also provide your own QR-code provider.
* [random_bytes()](http://php.net/manual/en/function.random-bytes.php), [OpenSSL](http://php.net/manual/en/book.openssl.php) or [Hash](http://php.net/manual/en/book.hash.php) depending on which built-in RNG you use (TwoFactorAuth will try to 'autodetect' and use the best available); however: feel free to provide your own (CS)RNG.
Optionally, you may need:
docs/optional-configuration.md
+1 -9
View File
@@ -21,15 +21,7 @@ Argument | Default value | Use
### RNG providers
This library also comes with some [Random Number Generator (RNG)](https://en.wikipedia.org/wiki/Random_number_generation) providers. The RNG provider generates a number of random bytes and returns these bytes as a string. These values are then used to create the secret. By default (no RNG provider specified) TwoFactorAuth will try to determine the best available RNG provider to use in this order.
1. [CSRNGProvider](https://github.com/RobThree/TwoFactorAuth/blob/master/lib/Providers/Rng/CSRNGProvider.php) for PHP7+
2. [OpenSSLRNGProvider](https://github.com/RobThree/TwoFactorAuth/blob/master/lib/Providers/Rng/OpenSSLRNGProvider.php) where openssl is available
3. [HashRNGProvider](https://github.com/RobThree/TwoFactorAuth/blob/master/lib/Providers/Rng/HashRNGProvider.php) **non-cryptographically secure** fallback
Each of these RNG providers have some constructor arguments that allow you to tweak some of the settings to use when creating the random bytes.
You can also implement your own by implementing the [`IRNGProvider` interface](https://github.com/RobThree/TwoFactorAuth/blob/master/lib/Providers/Rng/IRNGProvider.php).
Should you feel the need to use a CSPRNG different than `random_bytes()`, you can use the `rngprovider` argument of the constructor to provide an object implementing the [`IRNGProvider`](https://github.com/RobThree/TwoFactorAuth/blob/master/lib/Providers/Rng/IRNGProvider.php) interface.
### Time providers
lib/Providers/Rng/CSRNGProvider.php
-8
View File
@@ -13,12 +13,4 @@ class CSRNGProvider implements IRNGProvider
{
return random_bytes($bytecount); // PHP7+
}
/**
* {@inheritdoc}
*/
public function isCryptographicallySecure(): bool
{
return true;
}
}
lib/Providers/Rng/HashRNGProvider.php
-40
View File
@@ -1,40 +0,0 @@
<?php
declare(strict_types=1);
namespace RobThree\Auth\Providers\Rng;
use function in_array;
class HashRNGProvider implements IRNGProvider
{
public function __construct(private readonly string $algorithm = 'sha256')
{
$algos = array_values(hash_algos());
if (!in_array($this->algorithm, $algos, true)) {
throw new RNGException('Unsupported algorithm specified');
}
}
/**
* {@inheritdoc}
*/
public function getRandomBytes(int $bytecount): string
{
$result = '';
$hash = mt_rand();
for ($i = 0; $i < $bytecount; $i++) {
$hash = hash($this->algorithm, $hash . mt_rand(), true);
$result .= $hash[mt_rand(0, strlen($hash) - 1)];
}
return $result;
}
/**
* {@inheritdoc}
*/
public function isCryptographicallySecure(): bool
{
return false;
}
}
lib/Providers/Rng/IRNGProvider.php
-2
View File
@@ -7,6 +7,4 @@ namespace RobThree\Auth\Providers\Rng;
interface IRNGProvider
{
public function getRandomBytes(int $bytecount): string;
public function isCryptographicallySecure(): bool;
}
lib/Providers/Rng/OpenSSLRNGProvider.php
-29
View File
@@ -1,29 +0,0 @@
<?php
declare(strict_types=1);
namespace RobThree\Auth\Providers\Rng;
class OpenSSLRNGProvider implements IRNGProvider
{
public function __construct(private readonly bool $requirestrong = true)
{
}
/**
* {@inheritdoc}
*/
public function getRandomBytes(int $bytecount): string
{
// will throw an Exception on failure
return openssl_random_pseudo_bytes($bytecount, $crypto_strong);
}
/**
* {@inheritdoc}
*/
public function isCryptographicallySecure(): bool
{
return $this->requirestrong;
}
}
lib/TwoFactorAuth.php
+5 -41
View File
@@ -4,12 +4,12 @@ declare(strict_types=1);
namespace RobThree\Auth;
use function hash_equals;
use RobThree\Auth\Providers\Qr\IQRCodeProvider;
use RobThree\Auth\Providers\Qr\QRServerProvider;
use RobThree\Auth\Providers\Rng\CSRNGProvider;
use RobThree\Auth\Providers\Rng\HashRNGProvider;
use RobThree\Auth\Providers\Rng\IRNGProvider;
use RobThree\Auth\Providers\Rng\OpenSSLRNGProvider;
use RobThree\Auth\Providers\Time\HttpTimeProvider;
use RobThree\Auth\Providers\Time\ITimeProvider;
use RobThree\Auth\Providers\Time\LocalMachineTimeProvider;
@@ -51,14 +51,11 @@ class TwoFactorAuth
/**
* Create a new secret
*/
public function createSecret(int $bits = 80, bool $requirecryptosecure = true): string
public function createSecret(int $bits = 80): string
{
$secret = '';
$bytes = (int)ceil($bits / 5); // We use 5 bits of each byte (since we have a 32-character 'alphabet' / BASE32)
$rngprovider = $this->getRngProvider();
if ($requirecryptosecure && !$rngprovider->isCryptographicallySecure()) {
throw new TwoFactorAuthException('RNG provider is not cryptographically secure');
}
$rnd = $rngprovider->getRandomBytes($bytes);
for ($i = 0; $i < $bytes; $i++) {
$secret .= self::$_base32[ord($rnd[$i]) & 31]; //Mask out left 3 bits for 0-31 values
@@ -98,7 +95,7 @@ class TwoFactorAuth
for ($i = -$discrepancy; $i <= $discrepancy; $i++) {
$ts = $timestamp + ($i * $this->period);
$slice = $this->getTimeSlice($ts);
$timeslice = $this->codeEquals($this->getCode($secret, $ts), $code) ? $slice : $timeslice;
$timeslice = hash_equals($this->getCode($secret, $ts), $code) ? $slice : $timeslice;
}
return $timeslice > 0;
@@ -174,19 +171,7 @@ class TwoFactorAuth
*/
public function getRngProvider(): IRNGProvider
{
if ($this->rngprovider !== null) {
return $this->rngprovider;
}
if (function_exists('random_bytes')) {
return $this->rngprovider = new CSRNGProvider();
}
if (function_exists('openssl_random_pseudo_bytes')) {
return $this->rngprovider = new OpenSSLRNGProvider();
}
if (function_exists('hash')) {
return $this->rngprovider = new HashRNGProvider();
}
throw new TwoFactorAuthException('Unable to find a suited RNGProvider');
return $this->rngprovider ??= new CSRNGProvider();
}
public function getTimeProvider(): ITimeProvider
@@ -195,27 +180,6 @@ class TwoFactorAuth
return $this->timeprovider ??= new LocalMachineTimeProvider();
}
/**
* Timing-attack safe comparison of 2 codes (see http://blog.ircmaxell.com/2014/11/its-all-about-time.html)
*/
private function codeEquals(string $safe, string $user): bool
{
if (function_exists('hash_equals')) {
return hash_equals($safe, $user);
}
// In general, it's not possible to prevent length leaks. So it's OK to leak the length. The important part is that
// we don't leak information about the difference of the two strings.
if (strlen($safe) === strlen($user)) {
$result = 0;
$strlen = strlen($safe);
for ($i = 0; $i < $strlen; $i++) {
$result |= (ord($safe[$i]) ^ ord($user[$i]));
}
return $result === 0;
}
return false;
}
private function getTime(?int $time = null): int
{
return $time ?? $this->getTimeProvider()->getTime();
tests/Providers/Rng/CSRNGProviderTest.php
+3 -11
View File
@@ -11,19 +11,11 @@ class CSRNGProviderTest extends TestCase
{
use NeedsRngLengths;
/**
* @requires function random_bytes
*/
public function testCSRNGProvidersReturnExpectedNumberOfBytes(): void
{
if (function_exists('random_bytes')) {
$rng = new CSRNGProvider();
foreach ($this->rngTestLengths as $l) {
$this->assertSame($l, strlen($rng->getRandomBytes($l)));
}
$this->assertTrue($rng->isCryptographicallySecure());
} else {
$this->expectNotToPerformAssertions();
$rng = new CSRNGProvider();
foreach ($this->rngTestLengths as $l) {
$this->assertSame($l, strlen($rng->getRandomBytes($l)));
}
}
}
tests/Providers/Rng/HashRNGProviderTest.php
-26
View File
@@ -1,26 +0,0 @@
<?php
declare(strict_types=1);
namespace Tests\Providers\Rng;
use PHPUnit\Framework\TestCase;
use RobThree\Auth\Providers\Rng\HashRNGProvider;
class HashRNGProviderTest extends TestCase
{
use NeedsRngLengths;
/**
* @return void
*/
public function testHashRNGProvidersReturnExpectedNumberOfBytes()
{
$rng = new HashRNGProvider();
foreach ($this->rngTestLengths as $l) {
$this->assertSame($l, strlen($rng->getRandomBytes($l)));
}
$this->assertFalse($rng->isCryptographicallySecure());
}
}
tests/Providers/Rng/IRNGProviderTest.php
+3 -37
View File
@@ -7,46 +7,12 @@ namespace Tests\Providers\Rng;
use PHPUnit\Framework\TestCase;
use RobThree\Auth\Algorithm;
use RobThree\Auth\TwoFactorAuth;
use RobThree\Auth\TwoFactorAuthException;
class IRNGProviderTest extends TestCase
{
public function testCreateSecretThrowsOnInsecureRNGProvider(): void
public function testCreateSecret(): void
{
$rng = new TestRNGProvider();
$tfa = new TwoFactorAuth('Test', 6, 30, Algorithm::Sha1, null, $rng);
$this->expectException(TwoFactorAuthException::class);
$tfa->createSecret();
}
public function testCreateSecretOverrideSecureDoesNotThrowOnInsecureRNG(): void
{
$rng = new TestRNGProvider();
$tfa = new TwoFactorAuth('Test', 6, 30, Algorithm::Sha1, null, $rng);
$this->assertSame('ABCDEFGHIJKLMNOP', $tfa->createSecret(80, false));
}
public function testCreateSecretDoesNotThrowOnSecureRNGProvider(): void
{
$rng = new TestRNGProvider(true);
$tfa = new TwoFactorAuth('Test', 6, 30, Algorithm::Sha1, null, $rng);
$this->assertSame('ABCDEFGHIJKLMNOP', $tfa->createSecret());
}
public function testCreateSecretGeneratesDesiredAmountOfEntropy(): void
{
$rng = new TestRNGProvider(true);
$tfa = new TwoFactorAuth('Test', 6, 30, Algorithm::Sha1, null, $rng);
$this->assertSame('A', $tfa->createSecret(5));
$this->assertSame('AB', $tfa->createSecret(6));
$this->assertSame('ABCDEFGHIJKLMNOPQRSTUVWXYZ', $tfa->createSecret(128));
$this->assertSame('ABCDEFGHIJKLMNOPQRSTUVWXYZ234567', $tfa->createSecret(160));
$this->assertSame('ABCDEFGHIJKLMNOPQRSTUVWXYZ234567ABCDEFGHIJKLMNOPQRSTUVWXYZ234567', $tfa->createSecret(320));
$this->assertSame('ABCDEFGHIJKLMNOPQRSTUVWXYZ234567ABCDEFGHIJKLMNOPQRSTUVWXYZ234567A', $tfa->createSecret(321));
$tfa = new TwoFactorAuth('Test', 6, 30, Algorithm::Sha1, null, null);
$this->assertIsString($tfa->createSecret());
}
}
tests/Providers/Rng/OpenSSLRNGProviderTest.php
-39
View File
@@ -1,39 +0,0 @@
<?php
declare(strict_types=1);
namespace Tests\Providers\Rng;
use PHPUnit\Framework\TestCase;
use RobThree\Auth\Providers\Rng\OpenSSLRNGProvider;
class OpenSSLRNGProviderTest extends TestCase
{
use NeedsRngLengths;
/**
* @return void
*/
public function testStrongOpenSSLRNGProvidersReturnExpectedNumberOfBytes()
{
$rng = new OpenSSLRNGProvider(true);
foreach ($this->rngTestLengths as $l) {
$this->assertSame($l, strlen($rng->getRandomBytes($l)));
}
$this->assertTrue($rng->isCryptographicallySecure());
}
/**
* @return void
*/
public function testNonStrongOpenSSLRNGProvidersReturnExpectedNumberOfBytes()
{
$rng = new OpenSSLRNGProvider(false);
foreach ($this->rngTestLengths as $l) {
$this->assertSame($l, strlen($rng->getRandomBytes($l)));
}
$this->assertFalse($rng->isCryptographicallySecure());
}
}
tests/Providers/Rng/TestRNGProvider.php
-36
View File
@@ -1,36 +0,0 @@
<?php
declare(strict_types=1);
namespace Tests\Providers\Rng;
use RobThree\Auth\Providers\Rng\IRNGProvider;
class TestRNGProvider implements IRNGProvider
{
public function __construct(private readonly bool $isSecure = false)
{
}
/**
* {@inheritdoc}
*/
public function getRandomBytes(int $bytecount): string
{
$result = '';
for ($i = 0; $i < $bytecount; $i++) {
$result .= chr($i);
}
return $result;
}
/**
* {@inheritdoc}
*/
public function isCryptographicallySecure(): bool
{
return $this->isSecure;
}
}