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For some reason this question didn't leave me alone, so I went through your code and fixed the bugs until it worked: Before you go through this, I have two pieces of advice: <ol> <li>Don't convert back and forth between int values and hex/bin representations; convert to int values before any processing is done; makes the code much more readable.</li> <li>Use <a href="http://us2.php.net/manual/en/function.call-user-func.php" rel="noreferrer"><code>call_user_func()</code></a> and implement the GG -> G, II -> I functions only once.</li> </ol> Also, there is one subtle bug remaining; an input string made up exclusively of zero characters will not be encoded correctly; I'll leave fixing that as an exercise for the reader :-). <ul> <li>In <code>init()</code>:</li> </ul> What is appended is the length of the unpadded message in number of bits, not number of characters: <pre><code>- $len = strlen($string) + $len = strlen($string) * 8; $hex = strhex($string); // convert ascii string to hex </code></pre> also, you have to pad what you get from <code>hexbin</code> otherwise the subsequent call to <code>str_split</code> will get the alignment wrong: <pre><code>- $bin = hexbin($hex); + $bin = leftpad(hexbin($hex), $len); // convert hex string to bin $block = str_split($padded, 32); </code></pre> also, the byte order is little endian: <pre><code>+ foreach ($block as &$b) { + $b = implode('', array_reverse(str_split($b, 8))); + } </code></pre> <ul> <li>In <code>strhex()</code>:</li> </ul> There are a lot of padding errors like this; <code>dechex(ord("\1"))</code> is <code>'1'</code> not <code>'01'</code>: <pre><code>- $hex = $hex.dechex(ord($str[$i])); + $hex = $hex.leftpad(dechex(ord($str[$i])), 2); </code></pre> <ul> <li>In <code>pad()</code>:</li> </ul> The byte-order is litte endian (you're splitting into 32-bit words) and <code>truncate64()</code> is completely off the map :-): <pre><code>- $bLen = decbin($len); - if(strlen($bLen) > 64){ - $words = truncate64($bLen); - $bin .= $words[1].$words[0]; - } - else{ - while(strlen($bLen) < 64){ - $bLen .= "0"; - } - $words = str_split ($bLen, 32); - $bin .= $words[1].$words[0]; - } + $bLen = leftpad(decbin($len), 64); + $bin .= implode('', array_reverse(str_split($bLen, 8))); </code></pre> <ul> <li>In <code>F()</code>, <code>G()</code>, <code>H()</code>, <code>I()</code>:</li> </ul> Bitwise operators can't be used on binary strings: <pre><code>- $X = hexbin($X); - $Y = hexbin($Y); - $Z = hexbin($Z); - $calc = ... - $calc = bindec($calc); + $X = hexdec($X); + $Y = hexdec($Y); + $Z = hexdec($Z); + $calc = ... </code></pre> <ul> <li>In <code>FF()</code>, <code>GG()</code>, <code>HH()</code>, <code>II()</code>:</li> </ul> You are adding <code>$B</code> before rotation, it must be added afterwards; also, since you are going back and forth between string and int representations and <code>PHP_INT_SIZE</code> may be greater than 4 (e.g. on 64-bit platforms), you have to make sure you only use the lower 32-bits: <pre><code>- $A = hexdec($B) + (($A + H($B, $C, $D) + $M + $t)); //decimal + $A = ($A + H($B, $C, $D) + $M + $t) & 0xffffffff; //decimal + $A = rotate($A, $s); + $A = dechex((hexdec($B) + hexdec($A)) & 0xffffffff); </code></pre> <ul> <li>In <code>addVars()</code>:</li> </ul> <code>$A</code> is repeated for each addition, probably a copy-paste artifact :-): <pre><code>- $aa = $aa + $A; - $bb = $bb + $A; - $cc = $cc + $A; - $dd = $dd + $A; + $aa = ($aa + $A) & 0xffffffff; + $bb = ($bb + $B) & 0xffffffff; + $cc = ($cc + $C) & 0xffffffff; + $dd = ($dd + $D) & 0xffffffff; </code></pre> <ul> <li>In <code>rotate()</code>:</li> </ul> There is a padding bug (again) in your rotate function. Just throw it away and replace it with: <pre><code>+ function rotate ($decimal, $bits) { //returns hex + return dechex((($decimal << $bits) | ($decimal >> (32 - $bits))) & 0xffffffff); + } </code></pre> <ul> <li>In <code>MD()</code>:</li> </ul> Last but not least, you have to convert to little endian again: <pre><code>- $MD5 = $a.$b.$c.$d; + $MD5 = ''; + foreach (array($a, $b, $c, $d) as $x) { + $MD5 .= implode('', array_reverse(str_split(leftpad($x, 8), 2))); + } </code></pre> The missing <code>leftpad()</code> function: <pre><code>+ function leftpad($needs_padding, $alignment) + { + if (strlen($needs_padding) % $alignment) { + $pad_amount = $alignment - strlen($needs_padding) % $alignment; + $left_pad = implode('', array_fill(0, $pad_amount, '0')); + $needs_padding = $left_pad . $needs_padding; + } + return $needs_padding; + } </code></pre> Full edited source: <pre><code><?php function MD($string){ $a = "67452301"; $b = "EFCDAB89"; $c = "98BADCFE"; $d = "10325476"; $words = init($string); for($i = 0; $i <= count($words)/16-1; $i++){ $A = $a; $B = $b; $C = $c; $D = $d; /* ROUND 1 */ FF ($A, $B, $C, $D, $words[0 + ($i * 16)], 7, "d76aa478"); FF ($D, $A, $B, $C, $words[1 + ($i * 16)], 12, "e8c7b756"); FF ($C, $D, $A, $B, $words[2 + ($i * 16)], 17, "242070db"); FF ($B, $C, $D, $A, $words[3 + ($i * 16)], 22, "c1bdceee"); FF ($A, $B, $C, $D, $words[4 + ($i * 16)], 7, "f57c0faf"); FF ($D, $A, $B, $C, $words[5 + ($i * 16)], 12, "4787c62a"); FF ($C, $D, $A, $B, $words[6 + ($i * 16)], 17, "a8304613"); FF ($B, $C, $D, $A, $words[7 + ($i * 16)], 22, "fd469501"); FF ($A, $B, $C, $D, $words[8 + ($i * 16)], 7, "698098d8"); FF ($D, $A, $B, $C, $words[9 + ($i * 16)], 12, "8b44f7af"); FF ($C, $D, $A, $B, $words[10 + ($i * 16)], 17, "ffff5bb1"); FF ($B, $C, $D, $A, $words[11 + ($i * 16)], 22, "895cd7be"); FF ($A, $B, $C, $D, $words[12 + ($i * 16)], 7, "6b901122"); FF ($D, $A, $B, $C, $words[13 + ($i * 16)], 12, "fd987193"); FF ($C, $D, $A, $B, $words[14 + ($i * 16)], 17, "a679438e"); FF ($B, $C, $D, $A, $words[15 + ($i * 16)], 22, "49b40821"); /* ROUND 2 */ GG ($A, $B, $C, $D, $words[1 + ($i * 16)], 5, "f61e2562"); GG ($D, $A, $B, $C, $words[6 + ($i * 16)], 9, "c040b340"); GG ($C, $D, $A, $B, $words[11 + ($i * 16)], 14, "265e5a51"); GG ($B, $C, $D, $A, $words[0 + ($i * 16)], 20, "e9b6c7aa"); GG ($A, $B, $C, $D, $words[5 + ($i * 16)], 5, "d62f105d"); GG ($D, $A, $B, $C, $words[10 + ($i * 16)], 9, "02441453"); GG ($C, $D, $A, $B, $words[15 + ($i * 16)], 14, "d8a1e681"); GG ($B, $C, $D, $A, $words[4 + ($i * 16)], 20, "e7d3fbc8"); GG ($A, $B, $C, $D, $words[9 + ($i * 16)], 5, "21e1cde6"); GG ($D, $A, $B, $C, $words[14 + ($i * 16)], 9, "c33707d6"); GG ($C, $D, $A, $B, $words[3 + ($i * 16)], 14, "f4d50d87"); GG ($B, $C, $D, $A, $words[8 + ($i * 16)], 20, "455a14ed"); GG ($A, $B, $C, $D, $words[13 + ($i * 16)], 5, "a9e3e905"); GG ($D, $A, $B, $C, $words[2 + ($i * 16)], 9, "fcefa3f8"); GG ($C, $D, $A, $B, $words[7 + ($i * 16)], 14, "676f02d9"); GG ($B, $C, $D, $A, $words[12 + ($i * 16)], 20, "8d2a4c8a"); /* ROUND 3 */ HH ($A, $B, $C, $D, $words[5 + ($i * 16)], 4, "fffa3942"); HH ($D, $A, $B, $C, $words[8 + ($i * 16)], 11, "8771f681"); HH ($C, $D, $A, $B, $words[11 + ($i * 16)], 16, "6d9d6122"); HH ($B, $C, $D, $A, $words[14 + ($i * 16)], 23, "fde5380c"); HH ($A, $B, $C, $D, $words[1 + ($i * 16)], 4, "a4beea44"); HH ($D, $A, $B, $C, $words[4 + ($i * 16)], 11, "4bdecfa9"); HH ($C, $D, $A, $B, $words[7 + ($i * 16)], 16, "f6bb4b60"); HH ($B, $C, $D, $A, $words[10 + ($i * 16)], 23, "bebfbc70"); HH ($A, $B, $C, $D, $words[13 + ($i * 16)], 4, "289b7ec6"); HH ($D, $A, $B, $C, $words[0 + ($i * 16)], 11, "eaa127fa"); HH ($C, $D, $A, $B, $words[3 + ($i * 16)], 16, "d4ef3085"); HH ($B, $C, $D, $A, $words[6 + ($i * 16)], 23, "04881d05"); HH ($A, $B, $C, $D, $words[9 + ($i * 16)], 4, "d9d4d039"); HH ($D, $A, $B, $C, $words[12 + ($i * 16)], 11, "e6db99e5"); HH ($C, $D, $A, $B, $words[15 + ($i * 16)], 16, "1fa27cf8"); HH ($B, $C, $D, $A, $words[2 + ($i * 16)], 23, "c4ac5665"); /* ROUND 4 */ II ($A, $B, $C, $D, $words[0 + ($i * 16)], 6, "f4292244"); II ($D, $A, $B, $C, $words[7 + ($i * 16)], 10, "432aff97"); II ($C, $D, $A, $B, $words[14 + ($i * 16)], 15, "ab9423a7"); II ($B, $C, $D, $A, $words[5 + ($i * 16)], 21, "fc93a039"); II ($A, $B, $C, $D, $words[12 + ($i * 16)], 6, "655b59c3"); II ($D, $A, $B, $C, $words[3 + ($i * 16)], 10, "8f0ccc92"); II ($C, $D, $A, $B, $words[10 + ($i * 16)], 15, "ffeff47d"); II ($B, $C, $D, $A, $words[1 + ($i * 16)], 21, "85845dd1"); II ($A, $B, $C, $D, $words[8 + ($i * 16)], 6, "6fa87e4f"); II ($D, $A, $B, $C, $words[15 + ($i * 16)], 10, "fe2ce6e0"); II ($C, $D, $A, $B, $words[6 + ($i * 16)], 15, "a3014314"); II ($B, $C, $D, $A, $words[13 + ($i * 16)], 21, "4e0811a1"); II ($A, $B, $C, $D, $words[4 + ($i * 16)], 6, "f7537e82"); II ($D, $A, $B, $C, $words[11 + ($i * 16)], 10, "bd3af235"); II ($C, $D, $A, $B, $words[2 + ($i * 16)], 15, "2ad7d2bb"); II ($B, $C, $D, $A, $words[9 + ($i * 16)], 21, "eb86d391"); addVars($a, $b, $c, $d, $A, $B, $C, $D); } $MD5 = ''; foreach (array($a, $b, $c, $d) as $x) { $MD5 .= implode('', array_reverse(str_split(leftpad($x, 8), 2))); } return $MD5; } /* General functions */ function hexbin($str){ $hexbinmap = array("0" => "0000" , "1" => "0001" , "2" => "0010" , "3" => "0011" , "4" => "0100" , "5" => "0101" , "6" => "0110" , "7" => "0111" , "8" => "1000" , "9" => "1001" , "A" => "1010" , "a" => "1010" , "B" => "1011" , "b" => "1011" , "C" => "1100" , "c" => "1100" , "D" => "1101" , "d" => "1101" , "E" => "1110" , "e" => "1110" , "F" => "1111" , "f" => "1111"); $bin = ""; for ($i = 0; $i < strlen($str); $i++) { $bin .= $hexbinmap[$str[$i]]; } $bin = ltrim($bin, '0'); // echo "Original: ".$str." New: ".$bin." "; return $bin; } function strhex($str){ $hex = ""; for ($i = 0; $i < strlen($str); $i++) { $hex = $hex.leftpad(dechex(ord($str[$i])), 2); } return $hex; } /* MD5-specific functions */ function init($string){ $len = strlen($string) * 8; $hex = strhex($string); // convert ascii string to hex $bin = leftpad(hexbin($hex), $len); // convert hex string to bin $padded = pad($bin); $padded = pad($padded, 1, $len); $block = str_split($padded, 32); foreach ($block as &$b) { $b = implode('', array_reverse(str_split($b, 8))); } return $block; } function pad($bin, $type=0, $len = 0){ if($type == 0){ $bin = $bin."1"; $buff = strlen($bin) % 512; if($buff != 448){ while(strlen($bin) % 512 != 448){ $bin = $bin."0"; } } } // append length (b) of string to latter 64 bits elseif($type == 1){ $bLen = leftpad(decbin($len), 64); $bin .= implode('', array_reverse(str_split($bLen, 8))); } return $bin; } /* MD5 base functions */ function F($X, $Y, $Z){ $X = hexdec($X); $Y = hexdec($Y); $Z = hexdec($Z); $calc = (($X & $Y) | ((~ $X) & $Z)); // X AND Y OR NOT X AND Z return $calc; } function G($X, $Y, $Z){ $X = hexdec($X); $Y = hexdec($Y); $Z = hexdec($Z); $calc = (($X & $Z) | ($Y & (~ $Z))); // X AND Z OR Y AND NOT Z return $calc; } function H($X, $Y, $Z){ $X = hexdec($X); $Y = hexdec($Y); $Z = hexdec($Z); $calc = ($X ^ $Y ^ $Z); // X XOR Y XOR Z return $calc; } function I($X, $Y, $Z){ $X = hexdec($X); $Y = hexdec($Y); $Z = hexdec($Z); $calc = ($Y ^ ($X | (~ $Z))) ; // Y XOR (X OR NOT Z) return $calc; } /* MD5 round functions */ /* $A - hex, $B - hex, $C - hex, $D - hex (F - dec) $M - binary $s - decimal $t - hex */ function FF(&$A, $B, $C, $D, $M, $s, $t){ $A = hexdec($A); $t = hexdec($t); $M = bindec($M); $A = ($A + F($B, $C, $D) + $M + $t) & 0xffffffff; //decimal $A = rotate($A, $s); $A = dechex((hexdec($B) + hexdec($A)) & 0xffffffff); } function GG(&$A, $B, $C, $D, $M, $s, $t){ $A = hexdec($A); $t = hexdec($t); $M = bindec($M); $A = ($A + G($B, $C, $D) + $M + $t) & 0xffffffff; //decimal $A = rotate($A, $s); $A = dechex((hexdec($B) + hexdec($A)) & 0xffffffff); } function HH(&$A, $B, $C, $D, $M, $s, $t){ $A = hexdec($A); $t = hexdec($t); $M = bindec($M); $A = ($A + H($B, $C, $D) + $M + $t) & 0xffffffff; //decimal $A = rotate($A, $s); $A = dechex((hexdec($B) + hexdec($A)) & 0xffffffff); } function II(&$A, $B, $C, $D, $M, $s, $t){ $A = hexdec($A); $t = hexdec($t); $M = bindec($M); $A = ($A + I($B, $C, $D) + $M + $t) & 0xffffffff; //decimal $A = rotate($A, $s); $A = dechex((hexdec($B) + hexdec($A)) & 0xffffffff); } // shift function rotate ($decimal, $bits) { //returns hex return dechex((($decimal << $bits) | ($decimal >> (32 - $bits))) & 0xffffffff); } function addVars(&$a, &$b, &$c, &$d, $A, $B, $C, $D){ $A = hexdec($A); $B = hexdec($B); $C = hexdec($C); $D = hexdec($D); $aa = hexdec($a); $bb = hexdec($b); $cc = hexdec($c); $dd = hexdec($d); $aa = ($aa + $A) & 0xffffffff; $bb = ($bb + $B) & 0xffffffff; $cc = ($cc + $C) & 0xffffffff; $dd = ($dd + $D) & 0xffffffff; $a = dechex($aa); $b = dechex($bb); $c = dechex($cc); $d = dechex($dd); } function leftpad($needs_padding, $alignment) { if (strlen($needs_padding) % $alignment) { $pad_amount = $alignment - strlen($needs_padding) % $alignment; $left_pad = implode('', array_fill(0, $pad_amount, '0')); $needs_padding = $left_pad . $needs_padding; } return $needs_padding; } </code></pre>
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