我试图在php中生成一个随机密码。

但是我得到的都是'a'返回类型是数组类型,我希望它是字符串。对如何修改代码有什么想法吗?

谢谢。

function randomPassword() {
    $alphabet = "abcdefghijklmnopqrstuwxyzABCDEFGHIJKLMNOPQRSTUWXYZ0123456789";
    for ($i = 0; $i < 8; $i++) {
        $n = rand(0, count($alphabet)-1);
        $pass[$i] = $alphabet[$n];
    }
    return $pass;
}

当前回答

我将发布一个答案,因为现有的一些答案很接近,但有一个:

一个比你想要的更小的字符空间,这样在相同的熵下,强制操作更容易,或者密码必须更长 不被认为是加密安全的RNG 一些第三方库的需求,我认为这可能是有趣的,展示什么可能需要自己做

这个答案将规避计数/strlen问题,因为生成的密码的安全性,至少在我看来,超越了你如何到达那里。我还将假设PHP > 5.3.0。

让我们把这个问题分解成几个组成部分:

使用一些安全的随机来源来获取随机数据 使用该数据并将其表示为一些可打印的字符串

对于第一部分,PHP > 5.3.0提供了函数openssl_random_pseudo_bytes。注意,虽然大多数系统使用加密强算法,但你必须检查,所以我们将使用包装器:

/**
 * @param int $length
 */
function strong_random_bytes($length)
{
    $strong = false; // Flag for whether a strong algorithm was used
    $bytes = openssl_random_pseudo_bytes($length, $strong);

    if ( ! $strong)
    {
        // System did not use a cryptographically strong algorithm 
        throw new Exception('Strong algorithm not available for PRNG.');
    }        

    return $bytes;
}

对于第二部分,我们将使用base64_encode,因为它接受一个字节字符串,并将生成一系列字母非常接近原始问题中指定的字母的字符。如果我们不介意在最后的字符串中出现+,/和=字符,并且我们希望结果至少有$n个字符长,我们可以简单地使用:

base64_encode(strong_random_bytes(intval(ceil($n * 3 / 4))));

The 3/4 factor is due to the fact that base64 encoding results in a string that has a length at least a third bigger than the byte string. The result will be exact for $n being a multiple of 4 and up to 3 characters longer otherwise. Since the extra characters are predominantly the padding character =, if we for some reason had a constraint that the password be an exact length, then we can truncate it to the length we want. This is especially because for a given $n, all passwords would end with the same number of these, so that an attacker who had access to a result password, would have up to 2 less characters to guess.


对于额外的学分,如果我们想要满足OP的问题中的确切规格,那么我们将不得不做更多的工作。在这里我将放弃碱基转换方法,而使用一个快速而肮脏的方法。这两种方法都需要产生比结果中所使用的更多的随机性,因为字母表有62个条目。

对于结果中的额外字符,我们可以简单地将它们从结果字符串中丢弃。如果我们在字节串中开始有8个字节,那么多达25%的base64字符将是这些“不受欢迎的”字符,因此简单地丢弃这些字符将导致不少于OP所需的字符串。然后我们可以简单地截断它以得到准确的长度:

$dirty_pass = base64_encode(strong_random_bytes(8)));
$pass = substr(str_replace(['/', '+', '='], ['', '', ''], $dirty_pass, 0, 8);

如果您生成较长的密码,填充字符=在中间结果中所占的比例会越来越小,这样您就可以实现更精简的方法(如果需要耗尽用于PRNG的熵池)。

其他回答

使用这个简单的代码生成med-strong密码长度为12

$password_string = '!@#$%*&abcdefghijklmnpqrstuwxyzABCDEFGHJKLMNPQRSTUWXYZ23456789';
$password = substr(str_shuffle($password_string), 0, 12);

一句话:

substr(str_shuffle('abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789') , 0 , 10 )

另一个(仅限linux)

function randompassword()
{
    $fp = fopen ("/dev/urandom", 'r');
    if (!$fp) { die ("Can't access /dev/urandom to get random data. Aborting."); }
    $random = fread ($fp, 1024); # 1024 bytes should be enough
    fclose ($fp);
    return trim (base64_encode ( md5 ($random, true)), "=");
}

一个简单的代码应该是这样的:

function generatePassword($len){
    $az = range("a","z");
    $AZ = range("A","Z");
    $num = range(0,9);
    $password = array_merge($az,$AZ,$num);
    return substr(str_shuffle(implode("",$password)),0, $len);
}
// testing 
$generate = range(8,32);
foreach($generate as $g){
    print "Len:{$g} = " . generatePassword($g)."\n";
}

输出:

Len:8 = G5uFhPKS
Len:9 = aU9x2NjvI
Len:10 = lJE9kxy3oD
Len:11 = tVh2CmpMdHW
Len:12 = ToXYHCPb58Ar
Len:13 = KIFVoLg5NdDzX
Len:14 = eFUabML28tXhf0
Len:15 = iegDCQcIMaxH0ST
Len:16 = sRvDmPo5IkaMqNO0
Len:17 = T5rwVDs6XGAqSU9KN
Len:18 = QwROWAfh1lpoCSaX0H
Len:19 = HP0trD4B9SQeUkNuAGV
Len:20 = P9Fdwqmu782ARHDiKGZM
Len:21 = 3Gxia9LPmCZM68dwe4YOf
Len:22 = ywFjuA2GDg0Oz8LVnCI94M
Len:23 = 16MiEVUgqPRueahlyvJfBz5
Len:24 = sPt0H9NSu5KrJTYeMXbOFgi7
Len:25 = QFKGTypaZlsMRnHPgNbVfIwxm
Len:26 = hbyJXtV81AEuMazS4GdFTINBUg
Len:27 = H3AiD95S4Z8xwMrz2L71GqUunaW
Len:28 = m8W2geIiO7Phc3H5Kyr1XCAs09Dv
Len:29 = MusNfYgOWnbrI62twRBvj38XEcDdi
Len:30 = VgNeILaRT2wvb4J7hzCMSHsquUBtnA
Len:31 = nhUvCxgOS94dsYjzBtcaTou1WIArMQP
Len:32 = AFSVQqCijuPMp0cGJNdDtzYX78erKB9w

Generates a strong password of length 8 containing at least one lower case letter, one uppercase letter, one digit, and one special character. You can change the length in the code too. function checkForCharacterCondition($string) { return (bool) preg_match('/(?=.*([A-Z]))(?=.*([a-z]))(?=.*([0-9]))(?=.*([~`\!@#\$%\^&\*\(\)_\{\}\[\]]))/', $string); } $j = 1; function generate_pass() { global $j; $allowedCharacters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ~`!@#$%^&*()_{}[]'; $pass = ''; $length = 8; $max = mb_strlen($allowedCharacters, '8bit') - 1; for ($i = 0; $i < $length; ++$i) { $pass .= $allowedCharacters[random_int(0, $max)]; } if (checkForCharacterCondition($pass)){ return '<br><strong>Selected password: </strong>'.$pass; }else{ echo 'Iteration '.$j.': <strong>'.$pass.'</strong> Rejected<br>'; $j++; return generate_pass(); } } echo generate_pass();