你如何创建“好”的?随机MD5哈希在PHP?
在几种情况下,我需要创建随机MD5散列。你知道这样做的最好/最安全的方法是什么吗?
For several cases I would need to create random md5 hashes. Do you know what the best / most secure ways of doing this are?
- 验证电子邮件地址
- 重置密码
- 用于身份验证的某种会话ID,而不是密码(例如:点击记住我,我不想将通行证存储在cookie中)
我知道 rand()
不应该用于安全相关的应用程序。出于这个原因,我去了:
I know that rand()
should not be used for security relevant applications. For that reason I went with:
md5( uniqid(mt_rand(),true) );
现在我阅读 uniqid()的/en/function.uniqid.phprel =nofollow> php手册,它不能用于安全目的。
Now I read in the php manual about uniqid()
, that it must not be used for security purposes. Which kind of makes sense because it usually just gives something like a timestamp.
但是,如果结合随机前缀 - mt_rand(),这很好吗?
- 像我这样做,还是有更好的应该在这种情况下使用?
But is it fine when combined with a random prefix - mt_rand()
- like I do, or is there something better that should be used in this case?
Thx提前!
你不需要MD5哈希,你只需要一个随机字符串。这些与MD5完全无关。所以你需要的是一个好的PRNG。例如:
You don't need "MD5 hashes", you simply need a random string of characters. These need not have anything to do with MD5 at all. So all you need is a good PRNG. For instance:
$token = mcrypt_create_iv($rawLength, MCRYPT_DEV_URANDOM);
// or
$token = openssl_random_pseudo_bytes($rawLength);
// or
$token = file_get_contents('/dev/urandom', false, null, 0, $rawLength);
然后 base64_encode
或 bin2hex
获取ASCII字符串的原始值。
Then base64_encode
or bin2hex
the raw value to get an ASCII character string.