nextcloud /
server
@@ -46,104 +46,104 @@ |
||
| 46 | 46 | * @package OC\Security |
| 47 | 47 | */ |
| 48 | 48 | class Crypto implements ICrypto { |
| 49 | - /** @var AES $cipher */ |
|
| 50 | - private $cipher; |
|
| 51 | - /** @var int */ |
|
| 52 | - private $ivLength = 16; |
|
| 53 | - /** @var IConfig */ |
|
| 54 | - private $config; |
|
| 55 | - |
|
| 56 | - /** |
|
| 57 | - * @param IConfig $config |
|
| 58 | - * @param ISecureRandom $random |
|
| 59 | - */ |
|
| 60 | - public function __construct(IConfig $config) { |
|
| 61 | - $this->cipher = new AES(); |
|
| 62 | - $this->config = $config; |
|
| 63 | - } |
|
| 64 | - |
|
| 65 | - /** |
|
| 66 | - * @param string $message The message to authenticate |
|
| 67 | - * @param string $password Password to use (defaults to `secret` in config.php) |
|
| 68 | - * @return string Calculated HMAC |
|
| 69 | - */ |
|
| 70 | - public function calculateHMAC(string $message, string $password = ''): string { |
|
| 71 | - if ($password === '') { |
|
| 72 | - $password = $this->config->getSystemValue('secret'); |
|
| 73 | - } |
|
| 74 | - |
|
| 75 | - // Append an "a" behind the password and hash it to prevent reusing the same password as for encryption |
|
| 76 | - $password = hash('sha512', $password . 'a'); |
|
| 77 | - |
|
| 78 | - $hash = new Hash('sha512'); |
|
| 79 | - $hash->setKey($password); |
|
| 80 | - return $hash->hash($message); |
|
| 81 | - } |
|
| 82 | - |
|
| 83 | - /** |
|
| 84 | - * Encrypts a value and adds an HMAC (Encrypt-Then-MAC) |
|
| 85 | - * @param string $plaintext |
|
| 86 | - * @param string $password Password to encrypt, if not specified the secret from config.php will be taken |
|
| 87 | - * @return string Authenticated ciphertext |
|
| 88 | - */ |
|
| 89 | - public function encrypt(string $plaintext, string $password = ''): string { |
|
| 90 | - if ($password === '') { |
|
| 91 | - $password = $this->config->getSystemValue('secret'); |
|
| 92 | - } |
|
| 93 | - $this->cipher->setPassword($password); |
|
| 94 | - |
|
| 95 | - $iv = \random_bytes($this->ivLength); |
|
| 96 | - $this->cipher->setIV($iv); |
|
| 97 | - |
|
| 98 | - $ciphertext = bin2hex($this->cipher->encrypt($plaintext)); |
|
| 99 | - $iv = bin2hex($iv); |
|
| 100 | - $hmac = bin2hex($this->calculateHMAC($ciphertext.$iv, $password)); |
|
| 101 | - |
|
| 102 | - return $ciphertext.'|'.$iv.'|'.$hmac.'|2'; |
|
| 103 | - } |
|
| 104 | - |
|
| 105 | - /** |
|
| 106 | - * Decrypts a value and verifies the HMAC (Encrypt-Then-Mac) |
|
| 107 | - * @param string $authenticatedCiphertext |
|
| 108 | - * @param string $password Password to encrypt, if not specified the secret from config.php will be taken |
|
| 109 | - * @return string plaintext |
|
| 110 | - * @throws \Exception If the HMAC does not match |
|
| 111 | - * @throws \Exception If the decryption failed |
|
| 112 | - */ |
|
| 113 | - public function decrypt(string $authenticatedCiphertext, string $password = ''): string { |
|
| 114 | - if ($password === '') { |
|
| 115 | - $password = $this->config->getSystemValue('secret'); |
|
| 116 | - } |
|
| 117 | - $this->cipher->setPassword($password); |
|
| 118 | - |
|
| 119 | - $parts = explode('|', $authenticatedCiphertext); |
|
| 120 | - $partCount = \count($parts); |
|
| 121 | - if ($partCount < 3 || $partCount > 4) { |
|
| 122 | - throw new \Exception('Authenticated ciphertext could not be decoded.'); |
|
| 123 | - } |
|
| 124 | - |
|
| 125 | - $ciphertext = hex2bin($parts[0]); |
|
| 126 | - $iv = $parts[1]; |
|
| 127 | - $hmac = hex2bin($parts[2]); |
|
| 128 | - |
|
| 129 | - if ($partCount === 4) { |
|
| 130 | - $version = $parts[3]; |
|
| 131 | - if ($version === '2') { |
|
| 132 | - $iv = hex2bin($iv); |
|
| 133 | - } |
|
| 134 | - } |
|
| 135 | - |
|
| 136 | - $this->cipher->setIV($iv); |
|
| 137 | - |
|
| 138 | - if (!hash_equals($this->calculateHMAC($parts[0] . $parts[1], $password), $hmac)) { |
|
| 139 | - throw new \Exception('HMAC does not match.'); |
|
| 140 | - } |
|
| 141 | - |
|
| 142 | - $result = $this->cipher->decrypt($ciphertext); |
|
| 143 | - if ($result === false) { |
|
| 144 | - throw new \Exception('Decryption failed'); |
|
| 145 | - } |
|
| 146 | - |
|
| 147 | - return $result; |
|
| 148 | - } |
|
| 49 | + /** @var AES $cipher */ |
|
| 50 | + private $cipher; |
|
| 51 | + /** @var int */ |
|
| 52 | + private $ivLength = 16; |
|
| 53 | + /** @var IConfig */ |
|
| 54 | + private $config; |
|
| 55 | + |
|
| 56 | + /** |
|
| 57 | + * @param IConfig $config |
|
| 58 | + * @param ISecureRandom $random |
|
| 59 | + */ |
|
| 60 | + public function __construct(IConfig $config) { |
|
| 61 | + $this->cipher = new AES(); |
|
| 62 | + $this->config = $config; |
|
| 63 | + } |
|
| 64 | + |
|
| 65 | + /** |
|
| 66 | + * @param string $message The message to authenticate |
|
| 67 | + * @param string $password Password to use (defaults to `secret` in config.php) |
|
| 68 | + * @return string Calculated HMAC |
|
| 69 | + */ |
|
| 70 | + public function calculateHMAC(string $message, string $password = ''): string { |
|
| 71 | + if ($password === '') { |
|
| 72 | + $password = $this->config->getSystemValue('secret'); |
|
| 73 | + } |
|
| 74 | + |
|
| 75 | + // Append an "a" behind the password and hash it to prevent reusing the same password as for encryption |
|
| 76 | + $password = hash('sha512', $password . 'a'); |
|
| 77 | + |
|
| 78 | + $hash = new Hash('sha512'); |
|
| 79 | + $hash->setKey($password); |
|
| 80 | + return $hash->hash($message); |
|
| 81 | + } |
|
| 82 | + |
|
| 83 | + /** |
|
| 84 | + * Encrypts a value and adds an HMAC (Encrypt-Then-MAC) |
|
| 85 | + * @param string $plaintext |
|
| 86 | + * @param string $password Password to encrypt, if not specified the secret from config.php will be taken |
|
| 87 | + * @return string Authenticated ciphertext |
|
| 88 | + */ |
|
| 89 | + public function encrypt(string $plaintext, string $password = ''): string { |
|
| 90 | + if ($password === '') { |
|
| 91 | + $password = $this->config->getSystemValue('secret'); |
|
| 92 | + } |
|
| 93 | + $this->cipher->setPassword($password); |
|
| 94 | + |
|
| 95 | + $iv = \random_bytes($this->ivLength); |
|
| 96 | + $this->cipher->setIV($iv); |
|
| 97 | + |
|
| 98 | + $ciphertext = bin2hex($this->cipher->encrypt($plaintext)); |
|
| 99 | + $iv = bin2hex($iv); |
|
| 100 | + $hmac = bin2hex($this->calculateHMAC($ciphertext.$iv, $password)); |
|
| 101 | + |
|
| 102 | + return $ciphertext.'|'.$iv.'|'.$hmac.'|2'; |
|
| 103 | + } |
|
| 104 | + |
|
| 105 | + /** |
|
| 106 | + * Decrypts a value and verifies the HMAC (Encrypt-Then-Mac) |
|
| 107 | + * @param string $authenticatedCiphertext |
|
| 108 | + * @param string $password Password to encrypt, if not specified the secret from config.php will be taken |
|
| 109 | + * @return string plaintext |
|
| 110 | + * @throws \Exception If the HMAC does not match |
|
| 111 | + * @throws \Exception If the decryption failed |
|
| 112 | + */ |
|
| 113 | + public function decrypt(string $authenticatedCiphertext, string $password = ''): string { |
|
| 114 | + if ($password === '') { |
|
| 115 | + $password = $this->config->getSystemValue('secret'); |
|
| 116 | + } |
|
| 117 | + $this->cipher->setPassword($password); |
|
| 118 | + |
|
| 119 | + $parts = explode('|', $authenticatedCiphertext); |
|
| 120 | + $partCount = \count($parts); |
|
| 121 | + if ($partCount < 3 || $partCount > 4) { |
|
| 122 | + throw new \Exception('Authenticated ciphertext could not be decoded.'); |
|
| 123 | + } |
|
| 124 | + |
|
| 125 | + $ciphertext = hex2bin($parts[0]); |
|
| 126 | + $iv = $parts[1]; |
|
| 127 | + $hmac = hex2bin($parts[2]); |
|
| 128 | + |
|
| 129 | + if ($partCount === 4) { |
|
| 130 | + $version = $parts[3]; |
|
| 131 | + if ($version === '2') { |
|
| 132 | + $iv = hex2bin($iv); |
|
| 133 | + } |
|
| 134 | + } |
|
| 135 | + |
|
| 136 | + $this->cipher->setIV($iv); |
|
| 137 | + |
|
| 138 | + if (!hash_equals($this->calculateHMAC($parts[0] . $parts[1], $password), $hmac)) { |
|
| 139 | + throw new \Exception('HMAC does not match.'); |
|
| 140 | + } |
|
| 141 | + |
|
| 142 | + $result = $this->cipher->decrypt($ciphertext); |
|
| 143 | + if ($result === false) { |
|
| 144 | + throw new \Exception('Decryption failed'); |
|
| 145 | + } |
|
| 146 | + |
|
| 147 | + return $result; |
|
| 148 | + } |
|
| 149 | 149 | } |
