1*8ccd4a63SDavid du Colombier #include "os.h"
2*8ccd4a63SDavid du Colombier #include <mp.h>
3*8ccd4a63SDavid du Colombier #include <libsec.h>
4*8ccd4a63SDavid du Colombier
5*8ccd4a63SDavid du Colombier typedef struct State{
6*8ccd4a63SDavid du Colombier QLock lock;
7*8ccd4a63SDavid du Colombier int seeded;
8*8ccd4a63SDavid du Colombier uvlong seed;
9*8ccd4a63SDavid du Colombier DES3state des3;
10*8ccd4a63SDavid du Colombier } State;
11*8ccd4a63SDavid du Colombier static State x917state;
12*8ccd4a63SDavid du Colombier
13*8ccd4a63SDavid du Colombier static void
X917(uchar * rand,int nrand)14*8ccd4a63SDavid du Colombier X917(uchar *rand, int nrand)
15*8ccd4a63SDavid du Colombier {
16*8ccd4a63SDavid du Colombier int i, m, n8;
17*8ccd4a63SDavid du Colombier uvlong I, x;
18*8ccd4a63SDavid du Colombier
19*8ccd4a63SDavid du Colombier /* 1. Compute intermediate value I = Ek(time). */
20*8ccd4a63SDavid du Colombier I = nsec();
21*8ccd4a63SDavid du Colombier triple_block_cipher(x917state.des3.expanded, (uchar*)&I, 0); /* two-key EDE */
22*8ccd4a63SDavid du Colombier
23*8ccd4a63SDavid du Colombier /* 2. x[i] = Ek(I^seed); seed = Ek(x[i]^I); */
24*8ccd4a63SDavid du Colombier m = (nrand+7)/8;
25*8ccd4a63SDavid du Colombier for(i=0; i<m; i++){
26*8ccd4a63SDavid du Colombier x = I ^ x917state.seed;
27*8ccd4a63SDavid du Colombier triple_block_cipher(x917state.des3.expanded, (uchar*)&x, 0);
28*8ccd4a63SDavid du Colombier n8 = (nrand>8) ? 8 : nrand;
29*8ccd4a63SDavid du Colombier memcpy(rand, (uchar*)&x, n8);
30*8ccd4a63SDavid du Colombier rand += 8;
31*8ccd4a63SDavid du Colombier nrand -= 8;
32*8ccd4a63SDavid du Colombier x ^= I;
33*8ccd4a63SDavid du Colombier triple_block_cipher(x917state.des3.expanded, (uchar*)&x, 0);
34*8ccd4a63SDavid du Colombier x917state.seed = x;
35*8ccd4a63SDavid du Colombier }
36*8ccd4a63SDavid du Colombier }
37*8ccd4a63SDavid du Colombier
38*8ccd4a63SDavid du Colombier static void
X917init(void)39*8ccd4a63SDavid du Colombier X917init(void)
40*8ccd4a63SDavid du Colombier {
41*8ccd4a63SDavid du Colombier int n;
42*8ccd4a63SDavid du Colombier uchar mix[128];
43*8ccd4a63SDavid du Colombier uchar key3[3][8];
44*8ccd4a63SDavid du Colombier ulong *ulp;
45*8ccd4a63SDavid du Colombier
46*8ccd4a63SDavid du Colombier ulp = (ulong*)key3;
47*8ccd4a63SDavid du Colombier for(n = 0; n < sizeof(key3)/sizeof(ulong); n++)
48*8ccd4a63SDavid du Colombier ulp[n] = truerand();
49*8ccd4a63SDavid du Colombier setupDES3state(&x917state.des3, key3, nil);
50*8ccd4a63SDavid du Colombier X917(mix, sizeof mix);
51*8ccd4a63SDavid du Colombier x917state.seeded = 1;
52*8ccd4a63SDavid du Colombier }
53*8ccd4a63SDavid du Colombier
54*8ccd4a63SDavid du Colombier void
genrandom(uchar * p,int n)55*8ccd4a63SDavid du Colombier genrandom(uchar *p, int n)
56*8ccd4a63SDavid du Colombier {
57*8ccd4a63SDavid du Colombier qlock(&x917state.lock);
58*8ccd4a63SDavid du Colombier if(x917state.seeded == 0)
59*8ccd4a63SDavid du Colombier X917init();
60*8ccd4a63SDavid du Colombier X917(p, n);
61*8ccd4a63SDavid du Colombier qunlock(&x917state.lock);
62*8ccd4a63SDavid du Colombier }
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