PHP 使用 SHA256、SHA512 等 演算法的寫法

PHP 有 md5()、sha1() ... 等等 function，不過現在建議使用 SHA224 以上(註)，在 PHP 要怎麼寫呢？

註：下述摘錄自此篇：Mobilefish.com - MD5, SHA1, SHA224, SHA256, SHA384, SHA512 and RIPEMD160 hash generator

• MD5 is considered cryptographically broken and is unsuitable for further use.
• The SHA1 algorithm might not be secure enough for ongoing use. It is recommended not to use SHA1.
• SHA224: SHA224 produces a 224-bit (28-byte) hash value, typically rendered as a hexadecimal number, 56 digits long.
• SHA256: SHA256 produces a 256-bit (32-byte) hash value, typically rendered as a hexadecimal number, 64 digits long.
• SHA384: SHA384 produces a 384-bit (48-byte) hash value, typically rendered as a hexadecimal number, 96 digits long.
• SHA512: SHA512 produces a 512-bit (64-byte) hash value, typically rendered as a hexadecimal number, 128 digits long.
• RIPEMD160: RIPEMD160 produces a 160-bit (20-byte) hash value, typically rendered as a hexadecimal number, 40 digits long.

PHP 使用 SHA256、SHA512 等 雜湊演算法的寫法

雜湊(Hash)演算法越來越多，PHP 直接做了 hash() 來用，直接指定要用哪個雜湊演算法即可。

PHP hash() 使用範例

<?php
echo hash('sha256', 'abc');
echo hash('sha512', 'abc');
// md5, sha1.. 等等也都可以用此寫法
echo hash('md5', 'abc');
echo hash('sha1', 'abc');
?>

PHP hash() 有支援哪些雜湊演算法呢？

可以使用 hash_algos() 來查詢，範例如下：

<?php
// 列出 hash() 有哪些演算法可使用
print_r(hash_algos());
/*
Array
(
[0] => md2
[1] => md4
[2] => md5
[3] => sha1
[4] => sha224
[5] => sha256
[6] => sha384
[7] => sha512
[8] => ripemd128
[9] => ripemd160
[10] => ripemd256
[11] => ripemd320
[12] => whirlpool
[13] => tiger128,3
[14] => tiger160,3
[15] => tiger192,3
[16] => tiger128,4
[17] => tiger160,4
[18] => tiger192,4
[19] => snefru
[20] => snefru256
[21] => gost
[22] => gost-crypto
[23] => adler32
[24] => crc32
[25] => crc32b
[26] => fnv132
[27] => fnv1a32
[28] => fnv164
[29] => fnv1a64
[30] => joaat
[31] => haval128,3
[32] => haval160,3
[33] => haval192,3
[34] => haval224,3
[35] => haval256,3
[36] => haval128,4
[37] => haval160,4
[38] => haval192,4
[39] => haval224,4
[40] => haval256,4
[41] => haval128,5
[42] => haval160,5
[43] => haval192,5
[44] => haval224,5
[45] => haval256,5
)
*/
?>