<?php

/**

 * Portable PHP password hashing framework.

 * @package phpass

 * @since 2.5.0

 * @version 0.3 / WordPress

 */

#

# Written by Solar Designer <solar at openwall.com> in 2004-2006 and placed in

# the public domain.  Revised in subsequent years, still public domain.

#

# There's absolutely no warranty.

#

# Please be sure to update the Version line if you edit this file in any way.

# It is suggested that you leave the main version number intact, but indicate

# your project name (after the slash) and add your own revision information.

#

# Please do not change the "private" password hashing method implemented in

# here, thereby making your hashes incompatible.  However, if you must, please

# change the hash type identifier (the "$P$") to something different.

#

# Obviously, since this code is in the public domain, the above are not

# requirements (there can be none), but merely suggestions.

#

/**

 * Portable PHP password hashing framework.

 *

 * @package phpass

 * @version 0.3 / WordPress

 * @since 2.5.0

 */

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;

	}

}