note 91031 added to function.hash-hmac

The hotp algorithms above work with counter values less than 256, but since the counter can be larger, it's necessary to iterate through all the bytes of the counter: <?php function oath_hotp ($key, $counter) { // Counter //the counter value can be more than one byte long, so we need to go multiple times $cur_counter = array(0,0,0,0,0,0,0,0); for($i=7;$i>=0;$i--) { $cur_counter[$i] = pack ('C*', $counter); $counter = $counter >> 8; } $bin_counter = implode($cur_counter); // Pad to 8 chars if (strlen ($bin_counter) < 8) { $bin_counter = str_repeat (chr(0), 8 - strlen ($bin_counter)) . $bin_counter; } // HMAC $hash = hash_hmac ('sha1', $bin_counter, $key); return $hash; } function oath_truncate($hash, $length = 6) { // Convert to dec foreach(str_split($hash,2) as $hex) { $hmac_result[]=hexdec($hex); } // Find offset $offset = $hmac_result[19] & 0xf; // Algorithm from RFC return ( (($hmac_result[$offset+0] & 0x7f) << 24 ) | (($hmac_result[$offset+1] & 0xff) << 16 ) | (($hmac_result[$offset+2] & 0xff) << 8 ) | ($hmac_result[$offset+3] & 0xff) ) % pow(10,$length); } print "<pre>"; print "Compare results with:"; print " http://tools.ietf.org/html/draft-mraihi-oath-hmac-otp-04\n"; print "Count\tHash\t\t\t\t\t\tPin\n"; for($i=0;$i<=1024;$i=$i+128) { print $i."\t".($a=oath_hotp("12345678901234567890",$i)); print "\t".oath_truncate($a)."\n"; } ?> ---- Server IP: 208.69.120.35 Probable Submitter: 67.151.136.161 ---- Manual Page -- http://www.php.net/manual/en/function.hash-hmac.php Edit -- https://master.php.net/note/edit/91031 Del: integrated -- https://master.php.net/note/delete/91031/integrated Del: useless -- https://master.php.net/note/delete/91031/useless Del: bad code -- https://master.php.net/note/delete/91031/bad+code Del: spam -- https://master.php.net/note/delete/91031/spam Del: non-english -- https://master.php.net/note/delete/91031/non-english Del: in docs -- https://master.php.net/note/delete/91031/in+docs Del: other reasons-- https://master.php.net/note/delete/91031 Reject -- https://master.php.net/note/reject/91031 Search -- https://master.php.net/manage/user-notes.php