crypt(1) [freebsd man page]

ENIGMA(1)						    BSD General Commands Manual 						 ENIGMA(1)

NAME

     enigma, crypt -- very simple file encryption

SYNOPSIS

     enigma [-s] [-k] [password]
     crypt [-s] [-k] [password]

DESCRIPTION

     The enigma utility, also known as crypt is a very simple encryption program, working on a ``secret-key'' basis.  It operates as a filter,
     i.e., it encrypts or decrypts a stream of data from standard input, and writes the result to standard output.  Since its operation is fully
     symmetrical, feeding the encrypted data stream again through the engine (using the same secret key) will decrypt it.

     There are several ways to provide the secret key to the program.  By default, the program prompts the user on the controlling terminal for
     the key, using getpass(3).  This is the only safe way of providing it.

     Alternatively, the key can be provided as the sole command-line argument password when starting the program.  Obviously, this way the key can
     easily be spotted by other users running ps(1).  As yet another alternative, enigma can be given the option -k, and it will take the key from
     the environment variable CrYpTkEy.  While this at a first glance seems to be more secure than the previous option, it actually is not since
     environment variables can also be examined with ps(1).  Thus this option is mainly provided for compatibility with other implementations of
     enigma.

     When specifying the option -s, enigma modifies the encryption engine in a way that is supposed to make it a little more secure, but incompat-
     ible with other implementations.

   Warning
     The cryptographic value of enigma is rather small.  This program is only provided here for compatibility with other operating systems that
     also provide an implementation (usually called crypt(1) there).  For real encryption, refer to bdes(1), openssl(1), pgp(1)
     (ports/security/pgp), or gpg(1) (ports/security/gnupg).  However, restrictions for exporting, importing or using such tools might exist in
     some countries, so those stronger programs are not being shipped as part of the operating system by default.

ENVIRONMENT

	   CrYpTkEy  used to obtain the secret key when option -k has been given

EXAMPLES

	   man enigma | enigma > encrypted
	   Enter key: (XXX -- key not echoed)

     This will create an encrypted form of this man page, and store it in the file encrypted.

	   enigma XXX < encrypted

     This displays the previously created file on the terminal.

SEE ALSO

     bdes(1), gpg(1), openssl(1), pgp(1), ps(1), getpass(3)

HISTORY

     Implementations of crypt are very common among UNIX operating systems.  This implementation has been taken from the Cryptbreakers Workbench
     which is in the public domain.

BSD
								   May 14, 2004 							       BSD

Check Out this Related Man Page

crypt(1)						      General Commands Manual							  crypt(1)

NAME

       crypt - encode and decode files

SYNOPSIS

       [password]

DESCRIPTION

       reads  from the standard input and writes on the standard output.  password is a key that selects a particular transformation.  If no pass-
       word is given, demands a key from the terminal and turns off printing while the key is being typed in.  encrypts and decrypts with the same
       key:

       The latter command decrypts the file and prints the clear version.

       Files encrypted by are compatible with those treated by the editor in encryption mode (see ed(1)).

       Security  of encrypted files depends on three factors: the fundamental method must be hard to solve; direct search of the key space must be
       infeasible; "sneak paths" by which keys or clear text can become visible must be minimized.

       implements a one-rotor machine designed along the lines of the German Enigma, but with a 256-element rotor.   Methods  of  attack  on  such
       machines are widely known; thus provides minimal security.

       The transformation of a key into the internal settings of the machine is deliberately designed to be expensive; that is, to take a substan-
       tial fraction of a second to compute.  However, if keys are restricted to, for example, three lowercase letters, then encrypted	files  can
       be read by expending only a substantial fraction of five minutes of machine time.

       Since  the  key is an argument to the command, it is potentially visible to users executing the or a derivative (see ps(1)).  The choice of
       keys and key security are the most vulnerable aspect of

EXAMPLES

       The following example demonstrates the use of to edit a file that the user wants to keep strictly confidential:

	      ...
	      ...
	      ...

       Note that the option is the encryption mode of and prompts the user for the same key with which the file was encrypted.

WARNINGS

       If output is piped to and the encryption key is given on the command line, can leave terminal modes in a strange state  (see  nroff(1)  and
       stty(1)).

       If  two	or more files encrypted with the same key are concatenated and an attempt is made to decrypt the result, only the the first of the
       original files is decrypted correctly.

FILES

       for typed key

SEE ALSO

       ed(1), makekey(1), stty(1).

																	  crypt(1)

Linux and UNIX Man Pages

crypt(1) [freebsd man page]

Check Out this Related Man Page