1 PHP 的 HMAC_SHA1算法 实现 2 http://www.tuicool.com/articles/7322A3 3   4 function getSignature($str, $key) {   5     $signature = "";   6     if (function_exists('hash_hmac')) { 7         $signature = bin2hex(hash_hmac("sha1", $str, $key, true)); 8     } else { 9         $blocksize = 64;  10         $hashfunc = 'sha1';  11         if (strlen($key) > $blocksize) {  12             $key = pack('H*', $hashfunc($key));  13         }  14         $key = str_pad($key, $blocksize, chr(0x00));  15         $ipad = str_repeat(chr(0x36), $blocksize);  16         $opad = str_repeat(chr(0x5c), $blocksize);  17         $hmac = pack(  18                 'H*', $hashfunc(  19                         ($key ^ $opad) . pack(  20                                 'H*', $hashfunc(  21                                         ($key ^ $ipad) . $str  22                                 )  23                         )  24                 )  25         );  26         $signature = bin2hex($hmac);27     }  28     return $signature;  29 }