crypt(1)crypt(1)Namecrypt - encode/decode (available only if the Encryption layered product
Syntaxcrypt key < input.File > output.File
This reference page describes software that is available only if the
Encryption layered product is installed.
The command reads from the standard input and writes on the standard
output. You must supply a key which selects a particular transforma‐
tion. If no password is given, demands a key from the terminal and
turns off printing while the key is being typed in. The command
encrypts and decrypts with the same key.
Files encrypted by are compatible with those treated by the ed, ex and
vi editors in encryption mode.
The security of encrypted files depends on three factors: the fundamen‐
tal method must be hard to solve, direct search of the key space must
be infeasible, and sneak paths by which keys or clear text can become
visible must be minimized.
The command 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 known, but not widely; moreover the amount of work
required is likely to be large.
The transformation of a key into the internal settings of the machine
is deliberately designed to be expensive, for example, to take a sub‐
stantial fraction of a second to compute. However, if keys are
restricted to three lowercase letters, then encrypted files can be read
by expending only a substantial fraction of five minutes of machine
Since the key you choose is an argument to the command, it is poten‐
tially visible to users executing ps(1) or a derivative. To minimize
this possibility, destroys any record of the key immediately upon
entry. The most vulnerable aspect of is the choice of keys and key
The following examples use KEY as the key to encrypt and decrypt files.
The first example encrypts the file naming the resulting encrypted file
The second example decrypts the file naming the resulting decrypted
file The third example prints the encrypted file in clear text.
crypt KEY < plain.File > crypt.File
crypt KEY < crypt.File > decrypt.File
crypt KEY < crypt.File | pr
for typed key
See Alsoed(1), ex(1), vi(1), xsend(1), crypt(3), makekey(8)crypt(1)