1 0fc65b37 2004-03-21 devnull #include "os.h"
  2 0fc65b37 2004-03-21 devnull #include <libsec.h>
  3 0fc65b37 2004-03-21 devnull 
  4 0fc65b37 2004-03-21 devnull void
  5 0fc65b37 2004-03-21 devnull setupRC4state(RC4state *key, uchar *start, int n)
  6 0fc65b37 2004-03-21 devnull {
  7 0fc65b37 2004-03-21 devnull 	int t;
  8 0fc65b37 2004-03-21 devnull 	int index2;
  9 0fc65b37 2004-03-21 devnull 	uchar *state;
 10 0fc65b37 2004-03-21 devnull 	uchar *p, *e, *sp, *se;
 11 0fc65b37 2004-03-21 devnull 
 12 0fc65b37 2004-03-21 devnull 	state = key->state;
 13 0fc65b37 2004-03-21 devnull 	se = &state[256];
 14 0fc65b37 2004-03-21 devnull 	for(sp = state; sp < se; sp++)
 15 0fc65b37 2004-03-21 devnull 		*sp = sp - state;
 16 0fc65b37 2004-03-21 devnull 
 17 0fc65b37 2004-03-21 devnull 	key->x = 0;
 18 0fc65b37 2004-03-21 devnull 	key->y = 0;
 19 0fc65b37 2004-03-21 devnull 	index2 = 0;
 20 0fc65b37 2004-03-21 devnull 	e = start + n;
 21 0fc65b37 2004-03-21 devnull 	p = start;
 22 0fc65b37 2004-03-21 devnull 	for(sp = state; sp < se; sp++)
 23 0fc65b37 2004-03-21 devnull 	{
 24 0fc65b37 2004-03-21 devnull 		t = *sp;
 25 0fc65b37 2004-03-21 devnull 		index2 = (*p + t + index2) & 255;
 26 0fc65b37 2004-03-21 devnull 		*sp = state[index2];
 27 0fc65b37 2004-03-21 devnull 		state[index2] = t;
 28 0fc65b37 2004-03-21 devnull 		if(++p >= e)
 29 0fc65b37 2004-03-21 devnull 			p = start;
 30 0fc65b37 2004-03-21 devnull 	}
 31 0fc65b37 2004-03-21 devnull }
 32 0fc65b37 2004-03-21 devnull 
 33 0fc65b37 2004-03-21 devnull void
 34 0fc65b37 2004-03-21 devnull rc4(RC4state *key, uchar *p, int len)
 35 0fc65b37 2004-03-21 devnull {
 36 0fc65b37 2004-03-21 devnull 	int tx, ty;
 37 0fc65b37 2004-03-21 devnull 	int x, y;
 38 0fc65b37 2004-03-21 devnull 	uchar *state;
 39 0fc65b37 2004-03-21 devnull 	uchar *e;
 40 0fc65b37 2004-03-21 devnull 
 41 0fc65b37 2004-03-21 devnull 	x = key->x;
 42 0fc65b37 2004-03-21 devnull 	y = key->y;
 43 0fc65b37 2004-03-21 devnull 	state = &key->state[0];
 44 0fc65b37 2004-03-21 devnull 	for(e = p + len; p < e; p++)
 45 0fc65b37 2004-03-21 devnull 	{
 46 0fc65b37 2004-03-21 devnull 		x = (x+1)&255;
 47 0fc65b37 2004-03-21 devnull 		tx = state[x];
 48 0fc65b37 2004-03-21 devnull 		y = (y+tx)&255;
 49 0fc65b37 2004-03-21 devnull 		ty = state[y];
 50 0fc65b37 2004-03-21 devnull 		state[x] = ty;
 51 0fc65b37 2004-03-21 devnull 		state[y] = tx;
 52 0fc65b37 2004-03-21 devnull 		*p ^= state[(tx+ty)&255];
 53 0fc65b37 2004-03-21 devnull 	}
 54 0fc65b37 2004-03-21 devnull 	key->x = x;
 55 0fc65b37 2004-03-21 devnull 	key->y = y;
 56 0fc65b37 2004-03-21 devnull }
 57 0fc65b37 2004-03-21 devnull 
 58 0fc65b37 2004-03-21 devnull void
 59 0fc65b37 2004-03-21 devnull rc4skip(RC4state *key, int len)
 60 0fc65b37 2004-03-21 devnull {
 61 0fc65b37 2004-03-21 devnull 	int tx, ty;
 62 0fc65b37 2004-03-21 devnull 	int x, y;
 63 0fc65b37 2004-03-21 devnull 	uchar *state;
 64 0fc65b37 2004-03-21 devnull 	int i;
 65 0fc65b37 2004-03-21 devnull 
 66 0fc65b37 2004-03-21 devnull 	x = key->x;
 67 0fc65b37 2004-03-21 devnull 	y = key->y;
 68 0fc65b37 2004-03-21 devnull 	state = &key->state[0];
 69 0fc65b37 2004-03-21 devnull 	for(i=0; i<len; i++)
 70 0fc65b37 2004-03-21 devnull 	{
 71 0fc65b37 2004-03-21 devnull 		x = (x+1)&255;
 72 0fc65b37 2004-03-21 devnull 		tx = state[x];
 73 0fc65b37 2004-03-21 devnull 		y = (y+tx)&255;
 74 0fc65b37 2004-03-21 devnull 		ty = state[y];
 75 0fc65b37 2004-03-21 devnull 		state[x] = ty;
 76 0fc65b37 2004-03-21 devnull 		state[y] = tx;
 77 0fc65b37 2004-03-21 devnull 	}
 78 0fc65b37 2004-03-21 devnull 	key->x = x;
 79 0fc65b37 2004-03-21 devnull 	key->y = y;
 80 0fc65b37 2004-03-21 devnull }
 81 0fc65b37 2004-03-21 devnull 
 82 0fc65b37 2004-03-21 devnull void
 83 0fc65b37 2004-03-21 devnull rc4back(RC4state *key, int len)
 84 0fc65b37 2004-03-21 devnull {
 85 0fc65b37 2004-03-21 devnull 	int tx, ty;
 86 0fc65b37 2004-03-21 devnull 	int x, y;
 87 0fc65b37 2004-03-21 devnull 	uchar *state;
 88 0fc65b37 2004-03-21 devnull 	int i;
 89 0fc65b37 2004-03-21 devnull 
 90 0fc65b37 2004-03-21 devnull 	x = key->x;
 91 0fc65b37 2004-03-21 devnull 	y = key->y;
 92 0fc65b37 2004-03-21 devnull 	state = &key->state[0];
 93 0fc65b37 2004-03-21 devnull 	for(i=0; i<len; i++)
 94 0fc65b37 2004-03-21 devnull 	{
 95 0fc65b37 2004-03-21 devnull 		ty = state[x];
 96 0fc65b37 2004-03-21 devnull 		tx = state[y];
 97 0fc65b37 2004-03-21 devnull 		state[y] = ty;
 98 0fc65b37 2004-03-21 devnull 		state[x] = tx;
 99 0fc65b37 2004-03-21 devnull 		y = (y-tx)&255;
100 0fc65b37 2004-03-21 devnull 		x = (x-1)&255;
101 0fc65b37 2004-03-21 devnull 	}
102 0fc65b37 2004-03-21 devnull 	key->x = x;
103 0fc65b37 2004-03-21 devnull 	key->y = y;
104 0fc65b37 2004-03-21 devnull }