| .TH RC4 3 |
| .SH NAME |
| setupRC4state, rc4, rc4skip, rc4back - alleged rc4 encryption |
| .SH SYNOPSIS |
| .B #include <u.h> |
| .br |
| .B #include <libc.h> |
| .br |
| .B #include <mp.h> |
| .br |
| .B #include <libsec.h> |
| .PP |
| .B |
| void setupRC4state(RC4state *s, uchar *seed, int slen) |
| .PP |
| .B |
| void rc4(RC4state *s, uchar *data, int dlen) |
| .PP |
| .B |
| void rc4skip(RC4state *s, int nbytes) |
| .PP |
| .B |
| void rc4back(RC4state *s, int nbytes) |
| .SH DESCRIPTION |
| .PP |
| This is an algorithm alleged to be Rivest's RC4 encryption function. It is |
| a pseudo-random number generator with a 256 byte state and a long |
| cycle. The input buffer is XOR'd with the output of the |
| generator both to encrypt and to decrypt. The seed, entered |
| using |
| .IR setupRC4state , |
| can be any length. The generator can be run forward using |
| .IR rc4 , |
| skip over bytes using |
| .I rc4skip |
| to account lost transmissions, |
| or run backwards using |
| .I rc4back |
| to cover retransmitted data. |
| The |
| .I RC4state |
| structure keeps track of the algorithm. |
| .SH SOURCE |
| .B \*9/src/libsec |
| .SH SEE ALSO |
| .IR mp (3), |
| .IR aes (3), |
| .IR blowfish (3), |
| .IR des (3), |
| .IR dsa (3), |
| .IR elgamal (3), |
| .IR rsa (3), |
| .IR sechash (3), |
| .IR prime (3), |
| .IR rand (3) |
