Java 如何检查两个md5

我想检查java中的2 md5

这是我在在线数据库Basic4android中的密码，数据库中的结果md5是$p$B..TH1QJN4F2NHHG8PVTT2Y8EHMPG/

现在在安卓工作室，我想检查一下

Log.d("MD5", String.valueOf("$P$B..Th1QjN4F2nHHg8pvtT2IY8ehMPG/".equals(MD5("Basic4android"))));

这是我的MD5函数

public String MD5(String md5) {
    try {
        java.security.MessageDigest md = java.security.MessageDigest.getInstance("MD5");
        byte[] array = md.digest(md5.getBytes());
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < array.length; ++i) {
            sb.append(Integer.toHexString((array[i] & 0xFF) | 0x100).substring(1,3));
        }

        return sb.toString();
    } catch (java.security.NoSuchAlgorithmException e) {}

    return null;
}

---

但是它返回false。

您的管理面板无论它是什么错误，MD5都不能像这样$p$B..Th1QjN4F2nHHg8pvtT2IY8ehMPG/当您发布时，请确保它不是base64或其他算法

在java中，可以使用此函数获取字符串的MD5

public static final String getmd5ofstring(final String s) {
        final String MD5 = "MD5";
        try {
            // Create MD5 Hash
            MessageDigest digest = java.security.MessageDigest
                    .getInstance(MD5);
            digest.update(s.getBytes());
            byte messageDigest[] = digest.digest();

            // Create Hex String
            StringBuilder hexString = new StringBuilder();
            for (byte aMessageDigest : messageDigest) {
                String h = Integer.toHexString(0xFF & aMessageDigest);
                while (h.length() < 2)
                    h = "0" + h;
                hexString.append(h);
            }
            return hexString.toString().toUpparCase(Locale.US); // return md5

        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return "";
    }

---

终于，我自己找到了答案

有了这个php类，我可以用wordpress mdp检查简单的密码

---

MD5Basic4android是926d578d5392bf1cf4a32e9fbb3f3685。我知道，但在phpmyadmin数据库中写了$P$B。仅仅使用哈希函数是不够的，仅仅添加一个salt对提高安全性几乎没有什么作用。取而代之的是，在HMAC上随机添加盐，持续约100毫秒，并将盐与散列一起保存。使用PBKDF2 aka Rfc2898DeriveBytes、password_hash/password_verify、Bcrypt等函数和类似函数。关键是让攻击者花费大量时间通过暴力手段查找密码。保护您的用户很重要，请使用安全的密码方法。谢谢，但如何解密$P$B..Th1QjN4F2nHHg8pvtT2IY8ehMPG/或使用主密码检查？

String firstmd5 = getmd5ofstring("Basic4android"); // get first md5
String loadyousecondmd5here = ("ur md5 here the second one u want to compare").toUpparCase(Locale.US);

if (firstmd5.equals(loadyousecondmd5here)){
// its equal
}

<?php

$wp_hasher = new PasswordHash(8, TRUE);
$password_hashed = '$P$B/ljsoSW9uHKz9pmjZ6WiBJCZLGIv50';
$plain_password = 'TAHA25tt';

if($wp_hasher->CheckPassword($plain_password, $password_hashed)) {
    echo "YES, Matched";
} else {
    echo "No, Wrong Password";
}

class PasswordHash {
var $itoa64;
var $iteration_count_log2;
var $portable_hashes;
var $random_state;

/**
 * PHP5 constructor.
 */
function __construct( $iteration_count_log2, $portable_hashes )
{
    $this->itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';

    if ($iteration_count_log2 < 4 || $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 compatibility reasons
}

/**
 * PHP4 constructor.
 */
public function PasswordHash( $iteration_count_log2, $portable_hashes ) {
    self::__construct( $iteration_count_log2, $portable_hashes );
}

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) < $count) {
        $output = '';
        for ($i = 0; $i < $count; $i += 16) {
            $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 < $count)
            $value |= ord($input[$i]) << 8;
        $output .= $this->itoa64[($value >> 6) & 0x3f];
        if ($i++ >= $count)
            break;
        if ($i < $count)
            $value |= ord($input[$i]) << 16;
        $output .= $this->itoa64[($value >> 12) & 0x3f];
        if ($i++ >= $count)
            break;
        $output .= $this->itoa64[($value >> 18) & 0x3f];
    } while ($i < $count);

    return $output;
}

function gensalt_private($input)
{
    $output = '$P$';
    $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 "$P$", phpBB3 uses "$H$" for the same thing
    if ($id != '$P$' && $id != '$H$')
        return $output;

    $count_log2 = strpos($this->itoa64, $setting[3]);
    if ($count_log2 < 7 || $count_log2 > 30)
        return $output;

    $count = 1 << $count_log2;

    $salt = substr($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 << $count_log2) - 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 = '$2a$';
    $output .= chr(ord('0') + $this->iteration_count_log2 / 10);
    $output .= chr(ord('0') + $this->iteration_count_log2 % 10);
    $output .= '$';

    $i = 0;
    do {
        $c1 = ord($input[$i++]);
        $output .= $itoa64[$c1 >> 2];
        $c1 = ($c1 & 0x03) << 4;
        if ($i >= 16) {
            $output .= $itoa64[$c1];
            break;
        }

        $c2 = ord($input[$i++]);
        $c1 |= $c2 >> 4;
        $output .= $itoa64[$c1];
        $c1 = ($c2 & 0x0f) << 2;

        $c2 = ord($input[$i++]);
        $c1 |= $c2 >> 6;
        $output .= $itoa64[$c1];
        $output .= $itoa64[$c2 & 0x3f];
    } while (1);

    return $output;
}

function HashPassword($password)
{
    if ( strlen( $password ) > 4096 ) {
        return '*';
    }

    $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) < 3)
            $random = $this->get_random_bytes(3);
        $hash =
            crypt($password, $this->gensalt_extended($random));
        if (strlen($hash) == 20)
            return $hash;
    }

    if (strlen($random) < 6)
        $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)
{
    if ( strlen( $password ) > 4096 ) {
        return false;
    }

    $hash = $this->crypt_private($password, $stored_hash);
    if ($hash[0] == '*')
        $hash = crypt($password, $stored_hash);

    return $hash === $stored_hash;
}
}

?>