enigma, crypt -- very simple file encryption
enigma [-s] [-k] [password]
crypt [-s] [-k] [password]
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. It automatically detects whether the
input data stream is already encrypted, and switches into decryption mode
in this case.
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 isn't 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 incompatible
with other implementations.
Warning [Toc] [Back]
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. For real encryption, refer to bdes(1) (from
the DES distribution package), or pgp(1) (from the ports collection).
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.
CrYpTkEy used to obtain the secret key when option -k has been
given
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.
bdes(1), pgp(1), ps(1), getpass(3)
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.
FreeBSD 5.2.1 October 30, 1998 FreeBSD 5.2.1 [ Back ] |
