php man page for mcrypt_get_key_size

MCRYPT_GET_KEY_SIZE(3)							 1						    MCRYPT_GET_KEY_SIZE(3)

mcrypt_get_key_size - Gets the key size of the specified cipher

SYNOPSIS
       int mcrypt_get_key_size (int  $cipher)

DESCRIPTION
       int mcrypt_get_key_size (string	$cipher, string  $mode)

	The first prototype is when linked against libmcrypt 2.2.x, the second when linked against libmcrypt 2.4.x or 2.5.x.

       mcrypt_get_key_size(3) is used to get the size of a key of the specified $cipher (in combination with an encryption mode).

	It is more useful to use the mcrypt_enc_get_key_size(3) function as this uses the resource returned by mcrypt_module_open(3).

PARAMETERS
	      o $cipher
		-One of the MCRYPT_ciphername constants, or the name of the algorithm as string.

	      o $mode
		-One of the MCRYPT_MODE_modename constants, or one of the following strings: "ecb", "cbc", "cfb", "ofb", "nofb" or "stream".

RETURN VALUES
	Returns the maximum supported key size of the algorithm in bytes or FALSE on failure.

EXAMPLES
       Example #1

	      mcrypt_get_key_size(3) Example

	      <?php
		  echo mcrypt_get_key_size('tripledes', 'ecb');
	      ?>

	       The example above shows how to use this function when linked against libmcrypt 2.4.x or 2.5.x.

	      The above example will output:

	      24

SEE ALSO
       mcrypt_get_block_size(3), mcrypt_enc_get_key_size(3), mcrypt_encrypt(3).

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