1#include <openssl/bn.h>
2#include <openssl/rand.h>
3
4static int Rand(n)
5{
6    unsigned char x[2];
7    RAND_pseudo_bytes(x,2);
8    return (x[0] + 2*x[1]);
9}
10
11static void bug(char *m, BIGNUM *a, BIGNUM *b)
12{
13    printf("%s!\na=",m);
14    BN_print_fp(stdout, a);
15    printf("\nb=");
16    BN_print_fp(stdout, b);
17    printf("\n");
18    fflush(stdout);
19}
20
21main()
22{
23    BIGNUM *a=BN_new(), *b=BN_new(), *c=BN_new(), *d=BN_new(),
24	*C=BN_new(), *D=BN_new();
25    BN_RECP_CTX *recp=BN_RECP_CTX_new();
26    BN_CTX *ctx=BN_CTX_new();
27
28    for(;;) {
29	BN_pseudo_rand(a,Rand(),0,0);
30	BN_pseudo_rand(b,Rand(),0,0);
31	if (BN_is_zero(b)) continue;
32
33	BN_RECP_CTX_set(recp,b,ctx);
34	if (BN_div(C,D,a,b,ctx) != 1)
35	    bug("BN_div failed",a,b);
36	if (BN_div_recp(c,d,a,recp,ctx) != 1)
37	    bug("BN_div_recp failed",a,b);
38	else if (BN_cmp(c,C) != 0 || BN_cmp(c,C) != 0)
39	    bug("mismatch",a,b);
40    }
41}
42