class PasswordHashingTest

class PasswordHashingTest extends UnitTestCase {
    
    /**
     * The user for testing.
     *
     * @var \PHPUnit\Framework\MockObject\MockObject|\Drupal\user\UserInterface
     */
    protected $user;
    
    /**
     * The raw password.
     *
     * @var string
     */
    protected $password;
    
    /**
     * The md5 password.
     *
     * @var string
     */
    protected $md5HashedPassword;
    
    /**
     * The hashed password.
     *
     * @var string
     */
    protected $hashedPassword;
    
    /**
     * The password hasher under test.
     *
     * @var \Drupal\Core\Password\PhpassHashedPassword
     */
    protected $passwordHasher;
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() : void {
        parent::setUp();
        $this->password = $this->randomMachineName();
        $this->passwordHasher = new PhpassHashedPassword(1);
        $this->hashedPassword = $this->passwordHasher
            ->hash($this->password);
        $this->md5HashedPassword = 'U' . $this->passwordHasher
            ->hash(md5($this->password));
    }
    
    /**
     * Tests the hash count boundaries are enforced.
     *
     * @covers ::enforceLog2Boundaries
     */
    public function testWithinBounds() {
        $hasher = new FakePhpassHashedPassword();
        $this->assertEquals(PhpassHashedPassword::MIN_HASH_COUNT, $hasher->enforceLog2Boundaries(1), "Min hash count enforced");
        $this->assertEquals(PhpassHashedPassword::MAX_HASH_COUNT, $hasher->enforceLog2Boundaries(100), "Max hash count enforced");
    }
    
    /**
     * Tests a password needs update.
     *
     * @covers ::needsRehash
     */
    public function testPasswordNeedsUpdate() {
        // The md5 password should be flagged as needing an update.
        $this->assertTrue($this->passwordHasher
            ->needsRehash($this->md5HashedPassword), 'Upgraded md5 password hash needs a new hash.');
    }
    
    /**
     * Tests password hashing.
     *
     * @covers ::hash
     * @covers ::getCountLog2
     * @covers ::check
     * @covers ::needsRehash
     */
    public function testPasswordHashing() {
        $this->assertSame(PhpassHashedPassword::MIN_HASH_COUNT, $this->passwordHasher
            ->getCountLog2($this->hashedPassword), 'Hashed password has the minimum number of log2 iterations.');
        $this->assertNotEquals($this->hashedPassword, $this->md5HashedPassword, 'Password hashes not the same.');
        $this->assertTrue($this->passwordHasher
            ->check($this->password, $this->md5HashedPassword), 'Password check succeeds.');
        $this->assertTrue($this->passwordHasher
            ->check($this->password, $this->hashedPassword), 'Password check succeeds.');
        // Since the log2 setting hasn't changed and the user has a valid password,
        // userNeedsNewHash() should return FALSE.
        $this->assertFalse($this->passwordHasher
            ->needsRehash($this->hashedPassword), 'Does not need a new hash.');
    }
    
    /**
     * Tests password rehashing.
     *
     * @covers ::hash
     * @covers ::getCountLog2
     * @covers ::check
     * @covers ::needsRehash
     */
    public function testPasswordRehashing() {
        // Increment the log2 iteration to MIN + 1.
        $password_hasher = new PhpassHashedPassword(PhpassHashedPassword::MIN_HASH_COUNT + 1);
        $this->assertTrue($password_hasher->needsRehash($this->hashedPassword), 'Needs a new hash after incrementing the log2 count.');
        // Re-hash the password.
        $rehashed_password = $password_hasher->hash($this->password);
        $this->assertSame(PhpassHashedPassword::MIN_HASH_COUNT + 1, $password_hasher->getCountLog2($rehashed_password), 'Re-hashed password has the correct number of log2 iterations.');
        $this->assertNotEquals($rehashed_password, $this->hashedPassword, 'Password hash changed again.');
        // Now the hash should be OK.
        $this->assertFalse($password_hasher->needsRehash($rehashed_password), 'Re-hashed password does not need a new hash.');
        $this->assertTrue($password_hasher->check($this->password, $rehashed_password), 'Password check succeeds with re-hashed password.');
        $this->assertTrue($this->passwordHasher
            ->check($this->password, $rehashed_password), 'Password check succeeds with re-hashed password with original hasher.');
    }
    
    /**
     * Verifies that passwords longer than 512 bytes are not hashed.
     *
     * @covers ::crypt
     *
     * @dataProvider providerLongPasswords
     */
    public function testLongPassword($password, $allowed) {
        $hashed_password = $this->passwordHasher
            ->hash($password);
        if ($allowed) {
            $this->assertNotFalse($hashed_password);
        }
        else {
            $this->assertFalse($hashed_password);
        }
    }
    
    /**
     * Provides the test matrix for testLongPassword().
     */
    public function providerLongPasswords() {
        // '512 byte long password is allowed.'
        $passwords['allowed'] = [
            str_repeat('x', PasswordInterface::PASSWORD_MAX_LENGTH),
            TRUE,
        ];
        // 513 byte long password is not allowed.
        $passwords['too_long'] = [
            str_repeat('x', PasswordInterface::PASSWORD_MAX_LENGTH + 1),
            FALSE,
        ];
        // Check a string of 3-byte UTF-8 characters, 510 byte long password is
        // allowed.
        $len = floor(PasswordInterface::PASSWORD_MAX_LENGTH / 3);
        $diff = PasswordInterface::PASSWORD_MAX_LENGTH % 3;
        $passwords['utf8'] = [
            str_repeat('€', $len),
            TRUE,
        ];
        // 512 byte long password is allowed.
        $passwords['ut8_extended'] = [
            $passwords['utf8'][0] . str_repeat('x', $diff),
            TRUE,
        ];
        // Check a string of 3-byte UTF-8 characters, 513 byte long password is
        // allowed.
        $passwords['utf8_too_long'] = [
            str_repeat('€', $len + 1),
            FALSE,
        ];
        return $passwords;
    }

}