TwoFactorAuthenticator.php
225 lines
| 1 | <?php |
| 2 | |
| 3 | namespace { |
| 4 | /** |
| 5 | * PHP Class for handling Google Authenticator 2-factor authentication |
| 6 | * |
| 7 | * @author Michael Kliewe |
| 8 | * @copyright 2012 Michael Kliewe |
| 9 | * @license http://www.opensource.org/licenses/bsd-license.php BSD License |
| 10 | * @link http://www.phpgangsta.de/ |
| 11 | * |
| 12 | * small adjustments by @sgiehl / matomo.org |
| 13 | * - renamed class |
| 14 | * - removed method getQRCodeGoogleUrl |
| 15 | * small adjustments by matomo.org |
| 16 | * - use better random secret generator |
| 17 | */ |
| 18 | class TwoFactorAuthenticator |
| 19 | { |
| 20 | protected $_codeLength = 6; |
| 21 | /** |
| 22 | * Create new secret. |
| 23 | * 16 characters, randomly chosen from the allowed base32 characters. |
| 24 | * |
| 25 | * @param int $secretLength |
| 26 | * @return string |
| 27 | */ |
| 28 | public function createSecret($secretLength = 16) |
| 29 | { |
| 30 | $validChars = $this->_getBase32LookupTable(); |
| 31 | unset($validChars[32]); |
| 32 | // modified by matomo.org |
| 33 | return \Piwik\Common::getRandomString($secretLength, \implode('', $validChars)); |
| 34 | } |
| 35 | /** |
| 36 | * Calculate the code, with given secret and point in time |
| 37 | * |
| 38 | * @param string $secret |
| 39 | * @param int|null $timeSlice |
| 40 | * @return string |
| 41 | */ |
| 42 | public function getCode($secret, $timeSlice = null) |
| 43 | { |
| 44 | if ($timeSlice === null) { |
| 45 | $timeSlice = \floor(\time() / 30); |
| 46 | } |
| 47 | $secretkey = $this->_base32Decode($secret); |
| 48 | // Pack time into binary string |
| 49 | $time = \chr(0) . \chr(0) . \chr(0) . \chr(0) . \pack('N*', $timeSlice); |
| 50 | // Hash it with users secret key |
| 51 | $hm = \hash_hmac('SHA1', $time, $secretkey, \true); |
| 52 | // Use last nipple of result as index/offset |
| 53 | $offset = \ord(\substr($hm, -1)) & 0xf; |
| 54 | // grab 4 bytes of the result |
| 55 | $hashpart = \substr($hm, $offset, 4); |
| 56 | // Unpak binary value |
| 57 | $value = \unpack('N', $hashpart); |
| 58 | $value = $value[1]; |
| 59 | // Only 32 bits |
| 60 | $value = $value & 0x7fffffff; |
| 61 | $modulo = \pow(10, $this->_codeLength); |
| 62 | return \str_pad($value % $modulo, $this->_codeLength, '0', \STR_PAD_LEFT); |
| 63 | } |
| 64 | /** |
| 65 | * Check if the code is correct. This will accept codes starting from $discrepancy*30sec ago to $discrepancy*30sec from now |
| 66 | * |
| 67 | * @param string $secret |
| 68 | * @param string $code |
| 69 | * @param int $discrepancy This is the allowed time drift in 30 second units (8 means 4 minutes before or after) |
| 70 | * @param int|null $currentTimeSlice time slice if we want use other that time() |
| 71 | * @return bool |
| 72 | */ |
| 73 | public function verifyCode($secret, $code, $discrepancy = 1, $currentTimeSlice = null) |
| 74 | { |
| 75 | if ($currentTimeSlice === null) { |
| 76 | $currentTimeSlice = \floor(\time() / 30); |
| 77 | } |
| 78 | for ($i = -$discrepancy; $i <= $discrepancy; $i++) { |
| 79 | $calculatedCode = $this->getCode($secret, $currentTimeSlice + $i); |
| 80 | if ($calculatedCode == $code) { |
| 81 | return \true; |
| 82 | } |
| 83 | } |
| 84 | return \false; |
| 85 | } |
| 86 | /** |
| 87 | * Set the code length, should be >=6 |
| 88 | * |
| 89 | * @param int $length |
| 90 | * @return self |
| 91 | */ |
| 92 | public function setCodeLength($length) |
| 93 | { |
| 94 | $this->_codeLength = $length; |
| 95 | return $this; |
| 96 | } |
| 97 | /** |
| 98 | * Helper class to decode base32 |
| 99 | * |
| 100 | * @param $secret |
| 101 | * @return bool|string |
| 102 | */ |
| 103 | protected function _base32Decode($secret) |
| 104 | { |
| 105 | if (empty($secret)) { |
| 106 | return ''; |
| 107 | } |
| 108 | $base32chars = $this->_getBase32LookupTable(); |
| 109 | $base32charsFlipped = \array_flip($base32chars); |
| 110 | $paddingCharCount = \substr_count($secret, $base32chars[32]); |
| 111 | $allowedValues = array(6, 4, 3, 1, 0); |
| 112 | if (!\in_array($paddingCharCount, $allowedValues)) { |
| 113 | return \false; |
| 114 | } |
| 115 | for ($i = 0; $i < 4; $i++) { |
| 116 | if ($paddingCharCount == $allowedValues[$i] && \substr($secret, -$allowedValues[$i]) != \str_repeat($base32chars[32], $allowedValues[$i])) { |
| 117 | return \false; |
| 118 | } |
| 119 | } |
| 120 | $secret = \str_replace('=', '', $secret); |
| 121 | $secret = \str_split($secret); |
| 122 | $binaryString = ""; |
| 123 | for ($i = 0; $i < \count($secret); $i = $i + 8) { |
| 124 | $x = ""; |
| 125 | if (!\in_array($secret[$i], $base32chars)) { |
| 126 | return \false; |
| 127 | } |
| 128 | for ($j = 0; $j < 8; $j++) { |
| 129 | $x .= \str_pad(\base_convert($base32charsFlipped[@$secret[$i + $j]] ?? '', 10, 2), 5, '0', \STR_PAD_LEFT); |
| 130 | } |
| 131 | $eightBits = \str_split($x, 8); |
| 132 | for ($z = 0; $z < \count($eightBits); $z++) { |
| 133 | $binaryString .= ($y = \chr(\base_convert($eightBits[$z], 2, 10))) || \ord($y) == 48 ? $y : ""; |
| 134 | } |
| 135 | } |
| 136 | return $binaryString; |
| 137 | } |
| 138 | /** |
| 139 | * Helper class to encode base32 |
| 140 | * |
| 141 | * @param string $secret |
| 142 | * @param bool $padding |
| 143 | * @return string |
| 144 | */ |
| 145 | protected function _base32Encode($secret, $padding = \true) |
| 146 | { |
| 147 | if (empty($secret)) { |
| 148 | return ''; |
| 149 | } |
| 150 | $base32chars = $this->_getBase32LookupTable(); |
| 151 | $secret = \str_split($secret); |
| 152 | $binaryString = ""; |
| 153 | for ($i = 0; $i < \count($secret); $i++) { |
| 154 | $binaryString .= \str_pad(\base_convert(\ord($secret[$i]), 10, 2), 8, '0', \STR_PAD_LEFT); |
| 155 | } |
| 156 | $fiveBitBinaryArray = \str_split($binaryString, 5); |
| 157 | $base32 = ""; |
| 158 | $i = 0; |
| 159 | while ($i < \count($fiveBitBinaryArray)) { |
| 160 | $base32 .= $base32chars[\base_convert(\str_pad($fiveBitBinaryArray[$i], 5, '0'), 2, 10)]; |
| 161 | $i++; |
| 162 | } |
| 163 | if ($padding && ($x = \strlen($binaryString) % 40) != 0) { |
| 164 | if ($x == 8) { |
| 165 | $base32 .= \str_repeat($base32chars[32], 6); |
| 166 | } elseif ($x == 16) { |
| 167 | $base32 .= \str_repeat($base32chars[32], 4); |
| 168 | } elseif ($x == 24) { |
| 169 | $base32 .= \str_repeat($base32chars[32], 3); |
| 170 | } elseif ($x == 32) { |
| 171 | $base32 .= $base32chars[32]; |
| 172 | } |
| 173 | } |
| 174 | return $base32; |
| 175 | } |
| 176 | /** |
| 177 | * Get array with all 32 characters for decoding from/encoding to base32 |
| 178 | * |
| 179 | * @return array |
| 180 | */ |
| 181 | protected function _getBase32LookupTable() |
| 182 | { |
| 183 | return array( |
| 184 | 'A', |
| 185 | 'B', |
| 186 | 'C', |
| 187 | 'D', |
| 188 | 'E', |
| 189 | 'F', |
| 190 | 'G', |
| 191 | 'H', |
| 192 | // 7 |
| 193 | 'I', |
| 194 | 'J', |
| 195 | 'K', |
| 196 | 'L', |
| 197 | 'M', |
| 198 | 'N', |
| 199 | 'O', |
| 200 | 'P', |
| 201 | // 15 |
| 202 | 'Q', |
| 203 | 'R', |
| 204 | 'S', |
| 205 | 'T', |
| 206 | 'U', |
| 207 | 'V', |
| 208 | 'W', |
| 209 | 'X', |
| 210 | // 23 |
| 211 | 'Y', |
| 212 | 'Z', |
| 213 | '2', |
| 214 | '3', |
| 215 | '4', |
| 216 | '5', |
| 217 | '6', |
| 218 | '7', |
| 219 | // 31 |
| 220 | '=', |
| 221 | ); |
| 222 | } |
| 223 | } |
| 224 | } |
| 225 |