本文实例讲述了php实现aes256加密算法的方法，是较为常见的一种加密算法。分享给大家供大家参考。具体如下：
aes.class.php文件如下：
<?php /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /* aes implementation in php (c) chris veness 2005-2011. right of free use is granted for all */ /* commercial or non-commercial use under cc-by licence. no warranty of any form is offered. */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ class aes { /** * aes cipher function: encrypt 'input' with rijndael algorithm * * @param input message as byte-array (16 bytes) * @param w key schedule as 2d byte-array (nr+1 x nb bytes) - * generated from the cipher key by keyexpansion() * @return ciphertext as byte-array (16 bytes) */ public static function cipher($input, $w) { // main cipher function [§5.1] $nb = 4; // block size (in words): no of columns in state (fixed at 4 for aes) $nr = count($w)/$nb - 1; // no of rounds: 10/12/14 for 128/192/256-bit keys $state = array(); // initialise 4xnb byte-array 'state' with input [§3.4] for ($i=0; $i<4*$nb; $i++) $state[$i%4][floor($i/4)] = $input[$i]; $state = self::addroundkey($state, $w, 0, $nb); for ($round=1; $round<$nr; $round++) { // apply nr rounds $state = self::subbytes($state, $nb); $state = self::shiftrows($state, $nb); $state = self::mixcolumns($state, $nb); $state = self::addroundkey($state, $w, $round, $nb); } $state = self::subbytes($state, $nb); $state = self::shiftrows($state, $nb); $state = self::addroundkey($state, $w, $nr, $nb); $output = array(4*$nb); // convert state to 1-d array before returning [§3.4] for ($i=0; $i<4*$nb; $i++) $output[$i] = $state[$i%4][floor($i/4)]; return $output; } private static function addroundkey($state, $w, $rnd, $nb) { // xor round key into state s [§5.1.4] for ($r=0; $r<4; $r++) { for ($c=0; $c<$nb; $c++) $state[$r][$c] ^= $w[$rnd*4+$c][$r]; } return $state; } private static function subbytes($s, $nb) { // apply sbox to state s [§5.1.1] for ($r=0; $r<4; $r++) { for ($c=0; $c<$nb; $c++) $s[$r][$c] = self::$sbox[$s[$r][$c]]; } return $s; } private static function shiftrows($s, $nb) { // shift row r of state s left by r bytes [§5.1.2] $t = array(4); for ($r=1; $r<4; $r++) { for ($c=0; $c<4; $c++) $t[$c] = $s[$r][($c+$r)%$nb]; // shift into temp copy for ($c=0; $c<4; $c++) $s[$r][$c] = $t[$c]; // and copy back } // note that this will work for nb=4,5,6, but not 7,8 (always 4 for aes): return $s; // see fp.gladman.plus.com/cryptography_technology/rijndael/aes.spec.311.pdf } private static function mixcolumns($s, $nb) { // combine bytes of each col of state s [§5.1.3] for ($c=0; $c<4; $c++) { $a = array(4); // 'a' is a copy of the current column from 's' $b = array(4); // 'b' is a•{02} in gf(2^8) for ($i=0; $i<4; $i++) { $a[$i] = $s[$i][$c]; $b[$i] = $s[$i][$c]&0x80 ? $s[$i][$c]<<1 ^ 0x011b : $s[$i][$c]<<1; } // a[n] ^ b[n] is a•{03} in gf(2^8) $s[0][$c] = $b[0] ^ $a[1] ^ $b[1] ^ $a[2] ^ $a[3]; // 2*a0 + 3*a1 + a2 + a3 $s[1][$c] = $a[0] ^ $b[1] ^ $a[2] ^ $b[2] ^ $a[3]; // a0 * 2*a1 + 3*a2 + a3 $s[2][$c] = $a[0] ^ $a[1] ^ $b[2] ^ $a[3] ^ $b[3]; // a0 + a1 + 2*a2 + 3*a3 $s[3][$c] = $a[0] ^ $b[0] ^ $a[1] ^ $a[2] ^ $b[3]; // 3*a0 + a1 + a2 + 2*a3 } return $s; } /** * key expansion for rijndael cipher(): performs key expansion on cipher key * to generate a key schedule * * @param key cipher key byte-array (16 bytes) * @return key schedule as 2d byte-array (nr+1 x nb bytes) */ public static function keyexpansion($key) { // generate key schedule from cipher key [§5.2] $nb = 4; // block size (in words): no of columns in state (fixed at 4 for aes) $nk = count($key)/4; // key length (in words): 4/6/8 for 128/192/256-bit keys $nr = $nk + 6; // no of rounds: 10/12/14 for 128/192/256-bit keys $w = array(); $temp = array(); for ($i=0; $i<$nk; $i++) { $r = array($key[4*$i], $key[4*$i+1], $key[4*$i+2], $key[4*$i+3]); $w[$i] = $r; } for ($i=$nk; $i<($nb*($nr+1)); $i++) { $w[$i] = array(); for ($t=0; $t<4; $t++) $temp[$t] = $w[$i-1][$t]; if ($i % $nk == 0) { $temp = self::subword(self::rotword($temp)); for ($t=0; $t 6 && $i%$nk == 4) { $temp = self::subword($temp); } for ($t=0; $t<4; $t++) $w[$i][$t] = $w[$i-$nk][$t] ^ $temp[$t]; } return $w; } private static function subword($w) { // apply sbox to 4-byte word w for ($i=0; $i<4; $i++) $w[$i] = self::$sbox[$w[$i]]; return $w; } private static function rotword($w) { // rotate 4-byte word w left by one byte $tmp = $w[0]; for ($i=0; $i
aesctr.class.php文件如下：
<?php /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /* aes counter (ctr) mode implementation in php (c) chris veness 2005-2011. right of free use is */ /* granted for all commercial or non-commercial use under cc-by licence. no warranty of any */ /* form is offered. */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ class aesctr extends aes { /** * encrypt a text using aes encryption in counter mode of operation * - see http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf * * unicode multi-byte character safe * * @param plaintext source text to be encrypted * @param password the password to use to generate a key * @param nbits number of bits to be used in the key (128, 192, or 256) * @param keep keep 1:each not change 0:each change(default) * @return encrypted text */ public static function encrypt($plaintext, $password, $nbits, $keep=0) { $blocksize = 16; // block size fixed at 16 bytes / 128 bits (nb=4) for aes if (!($nbits==128 || $nbits==192 || $nbits==256)) return ''; // standard allows 128/192/256 bit keys // note php (5) gives us plaintext and password in utf8 encoding! // use aes itself to encrypt password to get cipher key (using plain password as source for // key expansion) - gives us well encrypted key $nbytes = $nbits/8; // no bytes in key $pwbytes = array(); for ($i=0; $i<$nbytes; $i++) $pwbytes[$i] = ord(substr($password,$i,1)) & 0xff; $key = aes::cipher($pwbytes, aes::keyexpansion($pwbytes)); $key = array_merge($key, array_slice($key, 0, $nbytes-16)); // expand key to 16/24/32 bytes long // initialise 1st 8 bytes of counter block with nonce (nist sp800-38a §b.2): [0-1] = millisec, // [2-3] = random, [4-7] = seconds, giving guaranteed sub-ms uniqueness up to feb 2106 $counterblock = array(); if($keep==0){ $nonce = floor(microtime(true)*1000); // timestamp: milliseconds since 1-jan-1970 $noncems = $nonce%1000; $noncesec = floor($nonce/1000); $noncernd = floor(rand(0, 0xffff)); }else{ $nonce = 10000; $noncems = $nonce%1000; $noncesec = floor($nonce/1000); $noncernd = 10000; } for ($i=0; $i<2; $i++) $counterblock[$i] = self::urs($noncems, $i*8) & 0xff; for ($i=0; $i<2; $i++) $counterblock[$i+2] = self::urs($noncernd, $i*8) & 0xff; for ($i=0; $i<4; $i++) $counterblock[$i+4] = self::urs($noncesec, $i*8) & 0xff; // and convert it to a string to go on the front of the ciphertext $ctrtxt = ''; for ($i=0; $i<8; $i++) $ctrtxt .= chr($counterblock[$i]); // generate key schedule - an expansion of the key into distinct key rounds for each round $keyschedule = aes::keyexpansion($key); //print_r($keyschedule); $blockcount = ceil(strlen($plaintext)/$blocksize); $ciphertxt = array(); // ciphertext as array of strings for ($b=0; $b<$blockcount; $b++) { // set counter (block #) in last 8 bytes of counter block (leaving nonce in 1st 8 bytes) // done in two stages for 32-bit ops: using two words allows us to go past 2^32 blocks (68gb) for ($c=0; $c<4; $c++) $counterblock[15-$c] = self::urs($b, $c*8) & 0xff; for ($c=0; $c<4; $c++) $counterblock[15-$c-4] = self::urs($b/0x100000000, $c*8); $ciphercntr = aes::cipher($counterblock, $keyschedule); // -- encrypt counter block -- // block size is reduced on final block $blocklength = $b<$blockcount-1 ? $blocksize : (strlen($plaintext)-1)%$blocksize+1; $cipherbyte = array(); for ($i=0; $i<$blocklength; $i++) { // -- xor plaintext with ciphered counter byte-by-byte -- $cipherbyte[$i] = $ciphercntr[$i] ^ ord(substr($plaintext, $b*$blocksize+$i, 1)); $cipherbyte[$i] = chr($cipherbyte[$i]); } $ciphertxt[$b] = implode('', $cipherbyte); // escape troublesome characters in ciphertext } // implode is more efficient than repeated string concatenation $ciphertext = $ctrtxt . implode('', $ciphertxt); $ciphertext = base64_encode($ciphertext); return $ciphertext; } /** * decrypt a text encrypted by aes in counter mode of operation * * @param ciphertext source text to be decrypted * @param password the password to use to generate a key * @param nbits number of bits to be used in the key (128, 192, or 256) * @return decrypted text */ public static function decrypt($ciphertext, $password, $nbits) { $blocksize = 16; // block size fixed at 16 bytes / 128 bits (nb=4) for aes if (!($nbits==128 || $nbits==192 || $nbits==256)) return ''; // standard allows 128/192/256 bit keys $ciphertext = base64_decode($ciphertext); // use aes to encrypt password (mirroring encrypt routine) $nbytes = $nbits/8; // no bytes in key $pwbytes = array(); for ($i=0; $i<$nbytes; $i++) $pwbytes[$i] = ord(substr($password,$i,1)) & 0xff; $key = aes::cipher($pwbytes, aes::keyexpansion($pwbytes)); $key = array_merge($key, array_slice($key, 0, $nbytes-16)); // expand key to 16/24/32 bytes long // recover nonce from 1st element of ciphertext $counterblock = array(); $ctrtxt = substr($ciphertext, 0, 8); for ($i=0; $i<8; $i++) $counterblock[$i] = ord(substr($ctrtxt,$i,1)); // generate key schedule $keyschedule = aes::keyexpansion($key); // separate ciphertext into blocks (skipping past initial 8 bytes) $nblocks = ceil((strlen($ciphertext)-8) / $blocksize); $ct = array(); for ($b=0; $b<$nblocks; $b++) $ct[$b] = substr($ciphertext, 8+$b*$blocksize, 16); $ciphertext = $ct; // ciphertext is now array of block-length strings // plaintext will get generated block-by-block into array of block-length strings $plaintxt = array(); for ($b=0; $b<$nblocks; $b++) { // set counter (block #) in last 8 bytes of counter block (leaving nonce in 1st 8 bytes) for ($c=0; $c operator nor unsigned ints * * @param a number to be shifted (32-bit integer) * @param b number of bits to shift a to the right (0..31) * @return a right-shifted and zero-filled by b bits */ private static function urs($a, $b) { $a &= 0xffffffff; $b &= 0x1f; // (bounds check) if ($a&0x80000000 && $b>0) { // if left-most bit set $a = ($a>>1) & 0x7fffffff; // right-shift one bit & clear left-most bit $a = $a >> ($b-1); // remaining right-shifts } else { // otherwise $a = ($a>>$b); // use normal right-shift } return $a; } } ?>
demo实例程序如下：

这里再介绍另一使用 php mcrypt 加解密方法：
/* aes 256 encrypt * @param string $ostr * @param string $securekey * @param string $type encrypt, decrypt */ function aes($ostr, $securekey, $type='encrypt'){ if($ostr==''){ return ''; } $key = $securekey; $iv = strrev($securekey); $td = mcrypt_module_open('rijndael-256', '', 'ofb', ''); mcrypt_generic_init($td, $key, $iv); $str = ''; switch($type){ case 'encrypt': $str = base64_encode(mcrypt_generic($td, $ostr)); break; case 'decrypt': $str = mdecrypt_generic($td, base64_decode($ostr)); break; } mcrypt_generic_deinit($td); return $str; } // demo $key = fdipzone201314showmethemoney!@#$; $str = show me the money; $ostr = aes($str, $key); echo string 1: $ostr
; $dstr = aes($ostr, $key, 'decrypt'); echo string 2: $dstr
;
希望本文所述对大家php程序设计的学习有所帮助。