ElggCrypto Class Reference

Public Member Functions
	getRandomBytes ($length)
	Generate a string of highly randomized bytes (over the full 8-bit range). More...
	getHmac ($data, $algo= 'sha256', $key= '')
	Get an HMAC token builder/validator object. More...
	getRandomString ($length, $chars=null)
	Generate a random string of specified length. More...
	areEqual ($str1, $str2)
	Are two strings equal (compared in constant time)? More...

Public Attributes
const	CHARS_PASSWORD = 'bcdfghjklmnpqrstvwxyz2346789'
	Character set for temp passwords (no risk of embedded profanity/glyphs that look similar) More...
const	CHARS_HEX = '0123456789abcdef'
	Character set for hexadecimal. More...

Protected Member Functions
	strlen ($binary_string)
	Count the number of bytes in a string. More...

Detailed Description

Definition at line 10 of file ElggCrypto.php.

Member Function Documentation

ElggCrypto::areEqual	(		$str1,
			$str2
	)

Are two strings equal (compared in constant time)?

Parameters

string	$str1	First string to compare
string	$str2	Second string to compare

Returns

bool

Based on password_verify in PasswordCompat

Author

Anthony Ferrara ircma.nosp@m.xell.nosp@m.@php..nosp@m.net http://www.opensource.org/licenses/mit-license.html MIT License

Copyright

2012 The Authors

Definition at line 245 of file ElggCrypto.php.

ElggCrypto::getHmac	(		$data,
			$algo = 'sha256',
			$key = ''
	)

Get an HMAC token builder/validator object.

Parameters

mixed	$data	HMAC data or serializable data
string	$algo	Hash algorithm
string	$key	Optional key (default uses site secret)

Returns

Definition at line 169 of file ElggCrypto.php.

ElggCrypto::getRandomBytes

(

$length

)

Generate a string of highly randomized bytes (over the full 8-bit range).

Parameters

int

$length

Number of bytes needed

Returns

string Random bytes

Author

George Argyros argyr.nosp@m.os.g.nosp@m.eorge.nosp@m.@gma.nosp@m.il.co.nosp@m.m

Copyright

2012, George Argyros. All rights reserved. Modified BSD Original Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.Neither the name of the nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GEORGE ARGYROS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Our primary choice for a cryptographic strong randomness function is openssl_random_pseudo_bytes.

If mcrypt extension is available then we use it to gather entropy from the operating system's PRNG. This is better than reading /dev/urandom directly since it avoids reading larger blocks of data than needed.

No build-in crypto randomness function found. We collect any entropy available in the PHP core PRNGs along with some filesystem info and memory stats. To make this data cryptographically strong we add data either from /dev/urandom or if its unavailable, we gather entropy by measuring the time needed to compute a number of SHA-1 hashes.

Definition at line 55 of file ElggCrypto.php.

ElggCrypto::getRandomString	(		$length,
			$chars = null
	)

Generate a random string of specified length.

Uses supplied character list for generating the new string. If no character list provided - uses Base64 URL character set.

Parameters

int	$length	Desired length of the string
string | null	$chars	Characters to be chosen from randomly. If not given, the Base64 URL charset will be used.

Returns

string The random string

Exceptions

InvalidArgumentException

Copyright

Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com) http://framework.zend.com/license/new-bsd New BSD License

See also

https://github.com/zendframework/zf2/blob/master/library/Zend/Math/Rand.php#L179

Definition at line 195 of file ElggCrypto.php.

ElggCrypto::strlen (   $binary_string )

protected

Count the number of bytes in a string.

We cannot simply use strlen() for this, because it might be overwritten by the mbstring extension. In this case, strlen() will count the number of characters based on the internal encoding. A sequence of bytes might be regarded as a single multibyte character.

Use elgg_strlen() to count UTF-characters instead of bytes.

Parameters

string

$binary_string

The input string

Returns

int The number of bytes

From PasswordCompat

Author

Anthony Ferrara ircma.nosp@m.xell.nosp@m.@php..nosp@m.net http://www.opensource.org/licenses/mit-license.html MIT License

Copyright

2012 The Authors

Definition at line 278 of file ElggCrypto.php.

Member Data Documentation

const ElggCrypto::CHARS_HEX = '0123456789abcdef'

Character set for hexadecimal.

Definition at line 20 of file ElggCrypto.php.

const ElggCrypto::CHARS_PASSWORD = 'bcdfghjklmnpqrstvwxyz2346789'

Character set for temp passwords (no risk of embedded profanity/glyphs that look similar)

Definition at line 15 of file ElggCrypto.php.

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The documentation for this class was generated from the following file:

• engine/classes/ElggCrypto.php