(PHP 5 >= 5.5.0, PHP 7, PHP 8)
openssl_pbkdf2 — 生成一个 PKCS5 v2 PBKDF2 字符串
$password,$salt,$key_length,$iterations,$digest_algo = "sha1"openssl_pbkdf2() 计算 PBKDF2 (Password-Based Key Derivation Function 2), 在PKCS5 v2中定义的一个密钥的推导函数。
password派生密钥所生成的密码。
saltPBKDF2 推荐一个不少于64位(8字节)的密码盐值。
key_length希望输出密钥的长度。
iterations需要的迭代次数 » NIST 建议至少10,000次。
digest_algo在openssl_get_md_methods()中可选的散列或摘要算法。默认是 SHA-1。
成功，返回原始二进制字符串 或者在失败时返回 false。
示例 #1 openssl_pbkdf2() 示例
<?php
$password = 'password';
$salt = openssl_random_pseudo_bytes(16);
$keyLength = 20;
$iterations = 600000;
$generated_key = openssl_pbkdf2($password, $salt, $keyLength, $iterations, 'sha256');
echo bin2hex($generated_key)."\n";
echo base64_encode($generated_key)."\n";
?>Despite the manual claiming that this is available in PHP 5.5 and above, this function wasn't made available in my local install.
I expect that having a prehistoric OpenSSL library version installed is the likely culprit.
If you're using PHP 5.5 and don't have this function available in your OpenSSL extension, look at the functionally equivalent hash_pbkdf2 function instead.