2 .\" enigma (aka. crypt) man page written by Joerg Wunsch.
4 .\" Since enigma itself is distributed in the Public Domain, this file
15 .Nd very simple file encryption
28 utility, also known as
32 simple encryption program, working on a
35 It operates as a filter, i.e.,
36 it encrypts or decrypts a
37 stream of data from standard input, and writes the result to standard
39 Since its operation is fully symmetrical, feeding the encrypted data
40 stream again through the engine (using the same secret key) will
43 There are several ways to provide the secret key to the program.
45 default, the program prompts the user on the controlling terminal for
48 This is the only safe way of providing it.
50 Alternatively, the key can be provided as the sole command-line
53 when starting the program.
54 Obviously, this way the key can easily be
55 spotted by other users running
57 As yet another alternative,
59 can be given the option
61 and it will take the key from the environment variable
63 While this at a first glance seems to be more secure than the previous
64 option, it actually is not since environment variables can also be
67 Thus this option is mainly provided for compatibility with other
71 When specifying the option
74 modifies the encryption engine in a way that is supposed to make it a
75 little more secure, but incompatible with other implementations.
78 The cryptographic value of
81 This program is only provided here for compatibility
82 with other operating systems that also provide an implementation
86 For real encryption, refer to
89 .Xr gpg 1 Pq Pa security/gnupg1 .
91 .Bl -tag -offset indent -width ".Ev CrYpTkEy"
93 used to obtain the secret key when option
98 .Bd -literal -offset indent
99 man enigma | enigma > encrypted
100 Enter key: (XXX \(em key not echoed)
103 This will create an encrypted form of this man page, and store it in
106 .Bd -literal -offset indent
107 enigma XXX < encrypted
110 This displays the previously created file on the terminal.
119 are very common among
122 This implementation has been taken from the
123 .Em Cryptbreakers Workbench
124 which is in the public domain.