2 .\" enigma (aka. crypt) man page written by Joerg Wunsch.
4 .\" Since enigma itself is distributed in the Public Domain, this file
7 .\" $FreeBSD: src/usr.bin/enigma/enigma.1,v 1.5.2.2 2002/06/20 23:45:48 charnier Exp $
15 .Nd very simple file encryption
28 utility, also known as
32 simple encryption program, working on a
34 basis. It operates as a filter, i. e. it encrypts or decrypts a
35 stream of data from standard input, and writes the result to standard
36 output. It automatically detects whether the input data stream is
37 already encrypted, and switches into decryption mode in this case.
39 There are several ways to provide the secret key to the program. By
40 default, the program prompts the user on the controlling terminal for
43 This is the only safe way of providing it.
45 Alternatively, the key can be provided as the sole command-line
48 when starting the program. Obviously, this way the key can easily be
49 spotted by other users running
51 As yet another alternative,
53 can be given the option
55 and it will take the key from the environment variable
57 While this at a first glance seems to be more secure than the previous
58 option, it actually isn't since environment variables can also be
61 Thus this option is mainly provided for compatibility with other
65 When specifying the option
68 modifies the encryption engine in a way that is supposed to make it a
69 little more secure, but incompatible with other implementations.
72 The cryptographic value of
74 is rather small. This program is only provided here for compatibility
75 with other operating systems that also provide an implementation. For
76 real encryption, refer to
78 (from the DES distribution package), or
80 (from the ports collection). However, restrictions for exporting,
81 importing or using such tools might exist in some countries, so those
82 stronger programs are not being shipped as part of the operating
85 .Bl -tag -offset indent -width "XXCrYpTkEy"
87 used to obtain the secret key when option
92 .Bd -literal -offset indent
93 man enigma | enigma > encrypted
94 Enter key: (XXX \(em key not echoed)
97 This will create an encrypted form of this man page, and store it in
100 .Bd -literal -offset indent
101 enigma XXX < encrypted
104 This displays the previously created file on the terminal.
113 are very common among
115 operating systems. This implementation has been taken from the
116 .Em Cryptbreakers Workbench
117 which is in the public domain.