+static void genprime_cb(int p, int n, void *arg)
+ {
+ char c='*';
+
+ if (p == 0) c='.';
+ if (p == 1) c='+';
+ if (p == 2) c='*';
+ if (p == 3) c='\n';
+ putc(c, stderr);
+ fflush(stderr);
+ (void)n;
+ (void)arg;
+ }
+
+int test_kron(BIO *bp, BN_CTX *ctx)
+ {
+ BIGNUM *a,*b,*r;
+ int i;
+ int legendre, kronecker;
+ int ret = 0;
+
+ a = BN_new();
+ b = BN_new();
+ r = BN_new();
+ if (a == NULL || b == NULL || r == NULL) goto err;
+
+ /* We test BN_kronecker(a, b, ctx) just for b odd (Jacobi symbol).
+ * In this case we know that if b is prime, then BN_kronecker(a, b, ctx)
+ * is congruent to $a^{(b-1)/2}$, modulo $b$ (Legendre symbol).
+ * So we generate a random prime b and compare these values
+ * for a number of random a's. (That is, we run the Solovay-Strassen
+ * primality test to confirm that b is prime, except that we
+ * don't want to test whether b is prime but whether BN_kronecker
+ * works.) */
+
+ if (!BN_generate_prime(b, 512, 0, NULL, NULL, genprime_cb, NULL)) goto err;
+ putc('\n', stderr);
+
+ for (i = 0; i < num0; i++)
+ {
+ if (!BN_rand(a, 512, 0, 0)) goto err;
+ a->neg = rand_neg();
+
+ /* r := (b-1)/2 (note that b is odd) */
+ if (!BN_copy(r, b)) goto err;
+ if (!BN_sub_word(r, 1)) goto err;
+ if (!BN_rshift1(r, r)) goto err;
+ /* r := a^r mod b */
+ if (!BN_mod_exp(r, a, r, b, ctx)) goto err;
+
+ if (BN_is_word(r, 1))
+ legendre = 1;
+ else
+ {
+ if (!BN_add_word(r, 1)) goto err;
+ if (0 != BN_cmp(r, b))
+ {
+ fprintf(stderr, "Legendre symbol computation failed\n");
+ goto err;
+ }
+ legendre = -1;
+ }
+
+ kronecker = BN_kronecker(a, b, ctx);
+ if (kronecker < -1) goto err;
+
+ if (legendre != kronecker)
+ {
+ fprintf(stderr, "legendre != kronecker; a = ");
+ BN_print_fp(stderr, a);
+ fprintf(stderr, ", a = ");
+ BN_print_fp(stderr, b);
+ fprintf(stderr, "\n");
+ goto err;
+ }
+
+ putc('.', stderr);
+ fflush(stderr);
+ }
+
+ putc('\n', stderr);
+ fflush(stderr);
+ ret = 1;
+ err:
+ if (a != NULL) BN_free(a);
+ if (b != NULL) BN_free(b);
+ if (r != NULL) BN_free(r);
+ return ret;
+ }
+
+int test_sqrt(BIO *bp, BN_CTX *ctx)
+ {
+ BIGNUM *a,*p,*r;
+ int i, j;
+ int ret = 0;
+
+ a = BN_new();
+ p = BN_new();
+ r = BN_new();
+ if (a == NULL || p == NULL || r == NULL) goto err;
+
+ for (i = 0; i < 16; i++)
+ {
+ if (i < 8)
+ {
+ unsigned primes[8] = { 2, 3, 5, 7, 11, 13, 17, 19 };
+
+ if (!BN_set_word(p, primes[i])) goto err;
+ }
+ else
+ {
+ if (!BN_set_word(a, 32)) goto err;
+ if (!BN_set_word(r, 2*i + 1)) goto err;
+
+ if (!BN_generate_prime(p, 256, 0, a, r, genprime_cb, NULL)) goto err;
+ putc('\n', stderr);
+ }
+
+ for (j = 0; j < num2; j++)
+ {
+ /* construct 'a' such that it is a square modulo p,
+ * but in general not a proper square and not reduced modulo p */
+ if (!BN_rand(r, 256, 0, 3)) goto err;
+ if (!BN_nnmod(r, r, p, ctx)) goto err;
+ if (!BN_mod_sqr(r, r, p, ctx)) goto err;
+ if (!BN_rand(a, 256, 0, 3)) goto err;
+ if (!BN_nnmod(a, a, p, ctx)) goto err;
+ if (!BN_mod_sqr(a, a, p, ctx)) goto err;
+ if (!BN_mul(a, a, r, ctx)) goto err;
+
+ if (!BN_mod_sqrt(r, a, p, ctx)) goto err;
+ if (!BN_mod_sqr(r, r, p, ctx)) goto err;
+
+ if (!BN_nnmod(a, a, p, ctx)) goto err;
+
+ if (BN_cmp(a, r) != 0)
+ {
+ fprintf(stderr, "BN_mod_sqrt failed: a = ");
+ BN_print_fp(stderr, a);
+ fprintf(stderr, ", r = ");
+ BN_print_fp(stderr, r);
+ fprintf(stderr, ", p = ");
+ BN_print_fp(stderr, p);
+ fprintf(stderr, "\n");
+ goto err;
+ }
+
+ putc('.', stderr);
+ fflush(stderr);
+ }
+
+ putc('\n', stderr);
+ fflush(stderr);
+ }
+ ret = 1;
+ err:
+ if (a != NULL) BN_free(a);
+ if (p != NULL) BN_free(p);
+ if (r != NULL) BN_free(r);
+ return ret;
+ }
+