Código PHP:
function hmacsha1($key,$data)
{
$blocksize=64;
$hashfunc='sha1';
if (strlen($key)>$blocksize) $key=pack('H*', $hashfunc($key));
$key=str_pad($key,$blocksize,chr(0x00));
$ipad=str_repeat(chr(0x36),$blocksize);
$opad=str_repeat(chr(0x5c),$blocksize);
$hmac = pack(
'H*',$hashfunc(
($key^$opad).pack(
'H*',$hashfunc(
($key^$ipad).$data
)
)
)
);
return bin2hex($hmac);
}
function stringHexaToBytes($st)
{
$res="";
for ($i=0;$i< strlen($st);$i+=2)
{
$c=substr($st,$i,2);
$res.=pack("H*",$c);
}
return($res);
}
