Commit 390555f31f7e1b436decbc9e90e41d65ebedc4c1
2019-01-16T22:45:01
Added overflow check in mp_prime_is_prime and some verbosity in demo.c
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diff --git a/bn_mp_prime_is_prime.c b/bn_mp_prime_is_prime.c
index 63d3725..8d96e6a 100644
--- a/bn_mp_prime_is_prime.c
+++ b/bn_mp_prime_is_prime.c
@@ -305,8 +305,12 @@ int mp_prime_is_prime(const mp_int *a, int t, int *result)
fips_rand &= mask;
}
#endif
- /* Ceil, because small numbers have a right to live, too, */
- len = (((int)fips_rand + DIGIT_BIT) / DIGIT_BIT);
+ if (fips_rand > ((unsigned int) INT_MAX - DIGIT_BIT)) {
+ len = INT_MAX / DIGIT_BIT;
+ }
+ else {
+ len = (((int)fips_rand + DIGIT_BIT) / DIGIT_BIT);
+ }
/* Unlikely. */
if (len < 0) {
ix--;
diff --git a/demo/demo.c b/demo/demo.c
index 0aeae25..2a65601 100644
--- a/demo/demo.c
+++ b/demo/demo.c
@@ -687,9 +687,21 @@ int main(void)
mp_set(&a,1u);
mp_mul_2d(&a,1119,&a);
mp_add_d(&a,53,&a);
- mp_prime_is_prime(&a, 8, &cnt);
+ err = mp_prime_is_prime(&a, 8, &cnt);
+ /* small problem */
+ if (err != MP_OKAY) {
+ printf("failed with err code %d\n", err);
+ printf("prime tested was: ");
+ mp_fwrite(&a,16,stdout);
+ putchar('\n');
+ return EXIT_FAILURE;
+ }
+ /* large problem */
if (cnt == MP_NO) {
- printf("A certified prime is a prime but mp_prime_is_prime says it not.\n");
+ printf("A certified prime is a prime but mp_prime_is_prime says it is not.\n");
+ printf("prime tested was: ");
+ mp_fwrite(&a,16,stdout);
+ putchar('\n');
return EXIT_FAILURE;
}
for (ix = 16; ix < 128; ix++) {
@@ -709,19 +721,42 @@ int main(void)
/* let's see if it's really a safe prime */
mp_sub_d(&a, 1uL, &a);
mp_div_2(&a, &a);
- mp_prime_is_prime(&a, 8, &cnt);
+ err = mp_prime_is_prime(&a, 8, &cnt);
+ /* small problem */
+ if (err != MP_OKAY) {
+ printf("failed with err code %d\n", err);
+ printf("prime tested was: ");
+ mp_fwrite(&a,16,stdout);
+ putchar('\n');
+ return EXIT_FAILURE;
+ }
+ /* large problem */
if (cnt != MP_YES) {
printf("sub is not prime!\n");
+ printf("prime failed was: ");
+ mp_fwrite(&a,16,stdout);
+ putchar('\n');
return EXIT_FAILURE;
}
+
}
/* Check regarding problem #143 */
#ifndef MP_8BIT
mp_read_radix(&a, "FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A63A3620FFFFFFFFFFFFFFFF",
16);
- mp_prime_strong_lucas_selfridge(&a, &cnt);
+ err = mp_prime_strong_lucas_selfridge(&a, &cnt);
+ if (err != MP_OKAY) {
+ printf("mp_prime_strong_lucas_selfridge failed with err code %d\n", err);
+ printf("prime tested was: ");
+ mp_fwrite(&a,16,stdout);
+ putchar('\n');
+ return EXIT_FAILURE;
+ }
if (cnt != MP_YES) {
printf("\n\nissue #143 - mp_prime_strong_lucas_selfridge FAILED!\n");
+ printf("prime tested was: ");
+ mp_fwrite(&a,16,stdout);
+ putchar('\n');
return EXIT_FAILURE;
}
#endif