CodeIgniter provides a set of compatibility functions that enable you to use functions what are otherwise natively available in PHP, but only in higher versions or depending on a certain extension.
Being custom implementations, these functions will also have some set of dependencies on their own, but are still useful if your PHP setup doesn't offer them natively.
Note
Much like the common functions <common_functions>, the compatibility functions are always available, as long as their dependencies are met.
This set of compatibility functions offers a "backport" of PHP's standard Password Hashing extension that is otherwise available only since PHP 5.5.
- PHP 5.3.7
CRYPT_BLOWFISHsupport forcrypt()
PASSWORD_BCRYPTPASSWORD_DEFAULT
.. php:function:: password_get_info($hash)
:param string $hash: Password hash
:returns: Information about the hashed password
:rtype: array
For more information, please refer to the `PHP manual for
password_get_info() <http://php.net/password_get_info>`_.
.. php:function:: password_hash($password, $algo[, $options = array()])
:param string $password: Plain-text password
:param int $algo: Hashing algorithm
:param array $options: Hashing options
:returns: Hashed password or FALSE on failure
:rtype: string
For more information, please refer to the `PHP manual for
password_hash() <http://php.net/password_hash>`_.
.. note:: Unless you provide your own (and valid) salt, this function
has a further dependency on an available CSPRNG source. Each
of the following would satisfy that:
- ``mcrypt_create_iv()`` with ``MCRYPT_DEV_URANDOM``
- ``openssl_random_pseudo_bytes()``
- /dev/arandom
- /dev/urandom
.. php:function:: password_needs_rehash()
:param string $hash: Password hash
:param int $algo: Hashing algorithm
:param array $options: Hashing options
:returns: TRUE if the hash should be rehashed to match the given algorithm and options, FALSE otherwise
:rtype: bool
For more information, please refer to the `PHP manual for
password_needs_rehash() <http://php.net/password_needs_rehash>`_.
.. php:function:: password_verify($password, $hash)
:param string $password: Plain-text password
:param string $hash: Password hash
:returns: TRUE if the password matches the hash, FALSE if not
:rtype: bool
For more information, please refer to the `PHP manual for
password_verify() <http://php.net/password_verify>`_.
This compatibility layer contains backports for the hash_equals()
and hash_pbkdf2() functions, which otherwise require PHP 5.6 and/or
PHP 5.5 respectively.
- None
.. php:function:: hash_equals($known_string, $user_string)
:param string $known_string: Known string
:param string $user_string: User-supplied string
:returns: TRUE if the strings match, FALSE otherwise
:rtype: string
For more information, please refer to the `PHP manual for
hash_equals() <http://php.net/hash_equals>`_.
.. php:function:: hash_pbkdf2($algo, $password, $salt, $iterations[, $length = 0[, $raw_output = FALSE]])
:param string $algo: Hashing algorithm
:param string $password: Password
:param string $salt: Hash salt
:param int $iterations: Number of iterations to perform during derivation
:param int $length: Output string length
:param bool $raw_output: Whether to return raw binary data
:returns: Password-derived key or FALSE on failure
:rtype: string
For more information, please refer to the `PHP manual for
hash_pbkdf2() <http://php.net/hash_pbkdf2>`_.
This set of compatibility functions offers limited support for PHP's Multibyte String extension. Because of the limited alternative solutions, only a few functions are available.
Note
When a character set parameter is ommited,
$config['charset'] will be used.
- iconv extension
Important
This dependency is optional and these functions will always be declared. If iconv is not available, they WILL fall-back to their non-mbstring versions.
Important
Where a character set is supplied, it must be supported by iconv and in a format that it recognizes.
Note
For you own dependency check on the actual mbstring
extension, use the MB_ENABLED constant.
.. php:function:: mb_strlen($str[, $encoding = NULL])
:param string $str: Input string
:param string $encoding: Character set
:returns: Number of characters in the input string or FALSE on failure
:rtype: string
For more information, please refer to the `PHP manual for
mb_strlen() <http://php.net/mb_strlen>`_.
.. php:function:: mb_strpos($haystack, $needle[, $offset = 0[, $encoding = NULL]])
:param string $haystack: String to search in
:param string $needle: Part of string to search for
:param int $offset: Search offset
:param string $encoding: Character set
:returns: Numeric character position of where $needle was found or FALSE if not found
:rtype: mixed
For more information, please refer to the `PHP manual for
mb_strpos() <http://php.net/mb_strpos>`_.
.. php:function:: mb_substr($str, $start[, $length = NULL[, $encoding = NULL]])
:param string $str: Input string
:param int $start: Position of first character
:param int $length: Maximum number of characters
:param string $encoding: Character set
:returns: Portion of $str specified by $start and $length or FALSE on failure
:rtype: string
For more information, please refer to the `PHP manual for
mb_substr() <http://php.net/mb_substr>`_.
This set of compatibility functions offers support for a few standard functions in PHP that otherwise require a newer PHP version.
- None
.. php:function:: array_column(array $array, $column_key[, $index_key = NULL])
:param array $array: Array to fetch results from
:param mixed $column_key: Key of the column to return values from
:param mixed $index_key: Key to use for the returned values
:returns: An array of values representing a single column from the input array
:rtype: array
For more information, please refer to the `PHP manual for
array_column() <http://php.net/array_column>`_.
.. php:function:: array_replace(array $array1[, ...])
:param array $array1: Array in which to replace elements
:param array ...: Array (or multiple ones) from which to extract elements
:returns: Modified array
:rtype: array
For more information, please refer to the `PHP manual for
array_replace() <http://php.net/array_replace>`_.
.. php:function:: array_replace_recursive(array $array1[, ...])
:param array $array1: Array in which to replace elements
:param array ...: Array (or multiple ones) from which to extract elements
:returns: Modified array
:rtype: array
For more information, please refer to the `PHP manual for
array_replace_recursive() <http://php.net/array_replace_recursive>`_.
.. important:: Only PHP's native function can detect endless recursion.
Unless you are running PHP 5.3+, be careful with references!
.. php:function:: hex2bin($data)
:param array $data: Hexadecimal representation of data
:returns: Binary representation of the given data
:rtype: string
For more information, please refer to the `PHP manual for hex2bin()
<http://php.net/hex2bin>`_.
.. php:function:: quoted_printable_encode($str)
:param string $str: Input string
:returns: 8bit-encoded string
:rtype: string
For more information, please refer to the `PHP manual for
quoted_printable_encode() <http://php.net/quoted_printable_encode>`_.