Reuse the WordPress PasswordHash Class in others projects

Password-hash-and-check.php

// To find the last-version of WP PasswordHash, search: wp_hash_password, wp_check_password
//    File: /wp-includes/class-phpass.php

// To save hash in database (updating password)
// "UPDATE {TABLE} SET password = '" . oro_password_hash( $password_new ) . "' WHERE id = $id"

// To check password with hash
if( ! oro_password_check( $password, $database[ 'password' ] ) ) {
    // PASSWORD FAILED
}

function oro_password_hash( $password ) {
    global $oro_hasher;

    if( empty( $ORO_PASSWORD_HASHER )  ) {
        include 'PasswordHash.php';
        $oro_hasher = new PasswordHash( 8, true );
    }

    return $oro_hasher->HashPassword( $password );
}

function oro_password_check( $input_password, $hashed_password ) {
    global $oro_hasher;

    if( empty( $oro_hasher )  ) {
        include 'PasswordHash.php';
        $oro_hasher = new PasswordHash( 8, true );
    }

    return $oro_hasher->CheckPassword( $input_password, $hashed_password );
}

PasswordHash.php

<?php
/**
 * Portable PHP password hashing framework.
 * @package phpass
 * @since 2.5.0
 * @version 0.3 / WordPress
 * @link http://www.openwall.com/phpass/
 */

#
# 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
 * @link http://www.openwall.com/phpass/
 * @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 = 8, $portable_hashes = true ) {
        $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;
    }
}