php man page for mcrypt_decrypt

MCRYPT_DECRYPT(3)							 1							 MCRYPT_DECRYPT(3)

mcrypt_decrypt - Decrypts crypttext with given parameters

SYNOPSIS
       string mcrypt_decrypt (string  $cipher, string  $key, string  $data, string  $mode, [string  $iv])

DESCRIPTION
	Decrypts the $data and returns the unencrypted data.

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

	      o $key
		-  The	key  with  which the data was encrypted. If the provided key size is not supported by the cipher, the function will emit a
		warning and return FALSE

	      o $data
		- The data that will be decrypted with the given $cipher and $mode. If the size of the data is not n * blocksize, the data will be
		padded with ' '.

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

	      o $iv
		-Used  for  the  initialization in CBC, CFB, OFB modes, and in some algorithms in STREAM mode. If the provided IV size is not sup-
		ported by the chaining mode or no IV was provided, but the chaining mode requires one, the function will emit a warning and return
		FALSE.

RETURN VALUES
	Returns the decrypted data as a string or FALSE on failure.

CHANGELOG
       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 5.6.0	|						    |
       |	|						    |
       |	|  Invalid   $key  and	$iv  sizes  are  no  longer |
       |	| accepted.  mcrypt_decrypt(3)	will  now  throw  a |
       |	| warning  and	return	FALSE  if  the	inputs	are |
       |	| invalid. Previously keys and IVs were padded with |
       |	| ' ' bytes to the next valid size.		    |
       |	|						    |
       +--------+---------------------------------------------------+
SEE ALSO
       mcrypt_encrypt(3).

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