RSA(1L)

TITLE
rsa, genprim, genrsa, rsaencode, rsadecode - support RSA message encryption

SYNOPSIS
rsaencode public
rsadecode secret
rsakeys [-l length] [-P prob] [-s secret] [-p public]
genprim length prob
genrsa

DESCRIPTION
The RSA programs provide facilities for RSA encryption and decryption of data. rsaencode encrypts data supplied on the standard input and writes the encrypted data to the standard output. It takes as argument public, the name of a file containing the public RSA encryption keys. rsadecode decrypts data supplied on the standard input and writes the drcrypted data to the standard output. It takes as argument secret, the name of a file containing the secret RSA encryption keys. rsakeys creates two files containing the public and secret keys used for encryption and decryption. By default these are in $HOME/.rsapublic and $HOME/.rsasecret respectively, or as specified by the environment variables $RSAPUBLIC and $RSASECRET if set. rsakeys takes the following options:

-l length
    The length of the base primes used to generate the keys, default 10.

-P prob
    Specify that the probability that the base primes are not actually prime should be 1 in 2^prob, default 1 in 2^20.

-s secret
    Specify that the secret keys, used for decryption, are to be stored in the file secret instead of the default outlined above.

-p public
    Specify that the public keys, used for encryption, are to be stored in the file public instead of the default outlined above.

genprim is used internally by rsakeys to generate probable primes for use as seeds to generate keys for the encryption and decryption processes. It places the prime on the standard output. genrsa takes two arguments:

length
    The length of the prime to be generated.

prob
    Specify that the probability that the number generated is not actually prime should be 1 in 2^prob.

genrsa reads two primes from its standard input, separated by a delimiter, and writes three numbers to its standard output, separated by the same delimiter. The first two numbers constiute the secret keys, the first and third numbers the public key.

BUGS
The encryption/decryption process seems to pad the decrypted message with NULs to a block boundary. Pure RSA encryption is used. I mean, we don't use DES or any other cipher to speed up the process. This means that the encryption process is slow.

FILES

${RSASECRET-$HOME/.rsasecret}
    Location of secret keys, used by rsakeys.

${RSAPUBLIC-$HOME/.rsapublic}
    Location of public keys, used by rsakeys.

AUTHOR
Mein Wissen ueber RSA und die anderen verwendeten Verfahren hab ich aus:
	Horster, Patrick:
	Kryptologie / von Patrick Horster. - Mannheim;
	Wien; Zuerich: Bibliographisches Institut, 1985.
	    (Reihe Informatik; 47)
	    ISBN 3-411-03106-9
	NE: GT
Martin Nicolay		( martin@trillian.megalon.de )
Fliederstr. 23
4100 Duisburg 1
W-Germany