WordPress 系統的使用者密碼是儲存在 wp_users 資料表的 user_pass 欄位，密碼是透過 Portable PHP password hashing framework 類產生的，密碼的形式是隨機且不可逆，同一個明文的密碼在不同時間，產生的密文也不一樣，相對來說較為安全。
二。密碼生成方式
> 隨機產生一個 salt 並將 salt 和 password 相加
> 進行了 count 次 md5 然後和 encode64 的 hash 數值累加
> 最後得到一個以 $P$開頭的密碼，這個密碼每次產生的結果都不一樣
以下為在 WordPress 中呼叫密碼生成的程式碼
[php] view plain copy print? 在 CODE 上檢視程式碼片派生到我的程式碼片
$password = 'abc';
global $wp_hasher;
if ( empty($wp_hasher) ) {
require_once( './wp-includes/class-phpass.php');
$wp_hasher = new PasswordHash(8, TRUE);
}
echo $wp_hasher->HashPassword($password);
?>
三。 WordPress 密碼生成與登入驗證
WordPress 中位置為 wp-includesclass-phpass.php
以下是 WordPress 中生成密碼的程式碼直接執行可檢視密碼的生成以及驗證過程
[php] view plain copy print? 在 CODE 上檢視程式碼片派生到我的程式碼片
class PasswordHash {
var $itoa64;
var $iteration_count_log2;
var $portable_hashes;
var $random_state;
function PasswordHash($iteration_count_log2, $portable_hashes)
{
$this->itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
if ($iteration_count_log2 31)
$iteration_count_log2 = 8;
$this->iteration_count_log2 = $iteration_count_log2;
$this->portable_hashes = $portable_hashes;
$this->random_state = microtime() . uniqid(rand(), TRUE); // removed getmypid() for compability reasons
}
function get_random_bytes($count)
{
$output = '';
if ( @is_readable('/dev/urandom') &&
($fh = @fopen('/dev/urandom', 'rb'))) {
$output = fread($fh, $count);
fclose($fh);
}
if (strlen($output)
$output = '';
for ($i = 0; $i
$this->random_state =
md5(microtime() . $this->random_state);
$output .=
pack('H*', md5($this->random_state));
}
$output = substr($output, 0, $count);
}
return $output;
}
function encode64($input, $count)
{
$output = '';
$i = 0;
do {
$value = ord($input[$i++]);
$output .= $this->itoa64[$value & 0x3f];
if ($i
$value |= ord($input[$i])
$output .= $this->itoa64[($value >> 6) & 0x3f];
if ($i++ >= $count)
break;
if ($i
$value |= ord($input[$i])
$output .= $this->itoa64[($value >> 12) & 0x3f];
if ($i++ >= $count)
break;
$output .= $this->itoa64[($value >> 18) & 0x3f];
} while ($i
return $output;
}
function gensalt_private($input)
{
$output = '$PXXXXX;
$output .= $this->itoa64[min($this->iteration_count_log2 +
((PHP_VERSION >= '5') ? 5 : 3), 30)];
$output .= $this->encode64($input, 6);
return $output;
}
function crypt_private($password, $setting)
{
$output = '*0';
if (substr($setting, 0, 2) == $output)
$output = '*1';
$id = substr($setting, 0, 3);
# We use "$P{1}quot;, phpBB3 uses "$H{1}quot; for the same thing
if ($id != '$PXXXXX && $id != '$HXXXXX)
return $output;
$count_log2 = strpos($this->itoa64, $setting[3]);
if ($count_log2 30)
return $output;
$count = 1
$salt = substr($setting, 4, 8);
if (strlen($salt) != 8)
return $output;
# We're kind of forced to use MD5 here since it's the only
# cryptographic primitive available in all versions of PHP
# currently in use. To implement our own low-level crypto
# in PHP would result in much worse performance and
# consequently in lower iteration counts and hashes that are
# quicker to crack (by non-PHP code).
if (PHP_VERSION >= '5') {
$hash = md5($salt . $password, TRUE);
do {
$hash = md5($hash . $password, TRUE);
} while (--$count);
} else {
$hash = pack('H*', md5($salt . $password));
do {
$hash = pack('H*', md5($hash . $password));
} while (--$count);
}
$output = substr($setting, 0, 12);
$output .= $this->encode64($hash, 16);
return $output;
}
function gensalt_extended($input)
{
$count_log2 = min($this->iteration_count_log2 + 8, 24);
# This should be odd to not reveal weak DES keys, and the
# maximum valid value is (2**24 - 1) which is odd anyway.
$count = (1
$output = '_';
$output .= $this->itoa64[$count & 0x3f];
$output .= $this->itoa64[($count >> 6) & 0x3f];
$output .= $this->itoa64[($count >> 12) & 0x3f];
$output .= $this->itoa64[($count >> 18) & 0x3f];
$output .= $this->encode64($input, 3);
return $output;
}
function gensalt_blowfish($input)
{
# This one needs to use a different order of characters and a
# different encoding scheme from the one in encode64() above.
# We care because the last character in our encoded string will
# only represent 2 bits. While two known implementations of
# bcrypt will happily accept and correct a salt string which
# has the 4 unused bits set to non-zero, we do not want to take
# chances and we also do not want to waste an additional byte
# of entropy.
$itoa64 = './ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
$output = '$2aXXXXX;
$output .= chr(ord('0') + $this->iteration_count_log2 / 10);
$output .= chr(ord('0') + $this->iteration_count_log2 % 10);
$output .= 'XXXXX;
$i = 0;
do {
$c1 = ord($input[$i++]);
$output .= $itoa64[$c1 >> 2];
$c1 = ($c1 & 0x03)
if ($i >= 16) {
$output .= $itoa64[$c1];
break;
}
$c2 = ord($input[$i++]);
$c1 |= $c2 >> 4;
$output .= $itoa64[$c1];
$c1 = ($c2 & 0x0f)
$c2 = ord($input[$i++]);
$c1 |= $c2 >> 6;
$output .= $itoa64[$c1];
$output .= $itoa64[$c2 & 0x3f];
} while (1);
return $output;
}
function HashPassword($password)
{
$random = '';
if (CRYPT_BLOWFISH == 1 && !$this->portable_hashes) {
$random = $this->get_random_bytes(16);
$hash =
crypt($password, $this->gensalt_blowfish($random));
if (strlen($hash) == 60)
return $hash;
}
if (CRYPT_EXT_DES == 1 && !$this->portable_hashes) {
if (strlen($random)
$random = $this->get_random_bytes(3);
$hash =
crypt($password, $this->gensalt_extended($random));
if (strlen($hash) == 20)
return $hash;
}
if (strlen($random)
$random = $this->get_random_bytes(6);
$hash =
$this->crypt_private($password,
$this->gensalt_private($random));
if (strlen($hash) == 34)
return $hash;
# Returning '*' on error is safe here, but would _not_ be safe
# in a crypt(3)-like function used _both_ for generating new
# hashes and for validating passwords against existing hashes.
return '*';
}
function CheckPassword($password, $stored_hash)
{
$hash = $this->crypt_private($password, $stored_hash);
if ($hash[0] == '*')
$hash = crypt($password, $stored_hash);
return $hash == $stored_hash;
}
}
//原始密碼
$passwordValue = "123456";
//生成密碼
$wp_hasher = new PasswordHash(8, TRUE);
$sigPassword = $wp_hasher->HashPassword($passwordValue);
echo "生成的密碼為:".$sigPassword;
echo "n";
//驗證密碼
$data = $wp_hasher->CheckPassword($passwordValue,$sigPassword);
if($data){
echo '密碼正確';
}else{
echo '密碼錯誤';
}
?>
此為一個 wordpres 密碼生成與登入驗證例項，其中 HashPassword 為生成密碼，CheckPassword 為驗證密碼
itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'; 為以上提到的生成 salt 的基礎字串。
備註：由於 csdn 程式碼顯示外掛對特殊字元的限制。 請將以上程式碼中 XXXXX 替換為 $' 注意有單引號，程式碼中一共有 5 處