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crypt(1) [opensolaris man page]

crypt(1)							   User Commands							  crypt(1)

NAME
crypt - encode or decode a file SYNOPSIS
crypt [password] DESCRIPTION
The crypt utility encrypts and decrypts the contents of a file. crypt reads from the standard input and writes on the standard output. The password is a key that selects a particular transformation. If no password is given, crypt demands a key from the terminal and turns off printing while the key is being typed in. crypt encrypts and decrypts with the same key: example% crypt key < clear.file > encrypted.file example% crypt key < encrypted.file | pr prints the contents of clear.file. Files encrypted by crypt are compatible with those treated by the editors ed(1), ex(1), and vi(1) in encryption mode. The 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 cleartext can become visible must be minimized. crypt 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 crypt 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 (say) three lower-case 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 crypt command, it is potentially visible to users executing ps(1) or a derivative command. To minimize this possibility, crypt takes care to destroy any record of the key immediately upon entry. No doubt the choice of keys and key security are the most vulnerable aspect of crypt. FILES
/dev/tty for typed key ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
des(1), ed(1), ex(1), ps(1), vi(1), attributes(5) SunOS 5.11 8 Mar 2005 crypt(1)

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crypt(1)						      General Commands Manual							  crypt(1)

NAME
crypt - encode/decode SYNOPSIS
crypt key < input.File > output.File DESCRIPTION
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 fundamental 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 time. Since the key you choose is an argument to the command, it is potentially visible to users executing the command or a derivative. To mini- mize this possibility, destroys any record of the key immediately upon entry. The most vulnerable aspect of is the choice of keys and key security. EXAMPLES
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 FILES
for typed key RELATED INFORMATION
ed(1), ex(1), vi(1), crypt(3), makekey(8) delim off crypt(1)

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