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-rw-r--r--security/nss/lib/freebl/mpi/utils/isprime.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/security/nss/lib/freebl/mpi/utils/isprime.c b/security/nss/lib/freebl/mpi/utils/isprime.c
new file mode 100644
index 000000000..d2d86957e
--- /dev/null
+++ b/security/nss/lib/freebl/mpi/utils/isprime.c
@@ -0,0 +1,89 @@
+/*
+ * isprime.c
+ *
+ * Probabilistic primality tester command-line tool
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "mpi.h"
+#include "mpprime.h"
+
+#define RM_TESTS 15 /* how many iterations of Rabin-Miller? */
+#define MINIMUM 1024 /* don't bother us with a < this */
+
+int g_tests = RM_TESTS;
+char *g_prog = NULL;
+
+int
+main(int argc, char *argv[])
+{
+ mp_int a;
+ mp_digit np = prime_tab_size; /* from mpprime.h */
+ int res = 0;
+
+ g_prog = argv[0];
+
+ if (argc < 2) {
+ fprintf(stderr, "Usage: %s <a>, where <a> is a decimal integer\n"
+ "Use '0x' prefix for a hexadecimal value\n",
+ g_prog);
+ return 1;
+ }
+
+ /* Read number of tests from environment, if present */
+ {
+ char *tmp;
+
+ if ((tmp = PR_GetEnvSecure("RM_TESTS")) != NULL) {
+ if ((g_tests = atoi(tmp)) <= 0)
+ g_tests = RM_TESTS;
+ }
+ }
+
+ mp_init(&a);
+ if (argv[1][0] == '0' && argv[1][1] == 'x')
+ mp_read_radix(&a, argv[1] + 2, 16);
+ else
+ mp_read_radix(&a, argv[1], 10);
+
+ if (mp_cmp_d(&a, MINIMUM) <= 0) {
+ fprintf(stderr, "%s: please use a value greater than %d\n",
+ g_prog, MINIMUM);
+ mp_clear(&a);
+ return 1;
+ }
+
+ /* Test for divisibility by small primes */
+ if (mpp_divis_primes(&a, &np) != MP_NO) {
+ printf("Not prime (divisible by small prime %d)\n", np);
+ res = 2;
+ goto CLEANUP;
+ }
+
+ /* Test with Fermat's test, using 2 as a witness */
+ if (mpp_fermat(&a, 2) != MP_YES) {
+ printf("Not prime (failed Fermat test)\n");
+ res = 2;
+ goto CLEANUP;
+ }
+
+ /* Test with Rabin-Miller probabilistic test */
+ if (mpp_pprime(&a, g_tests) == MP_NO) {
+ printf("Not prime (failed pseudoprime test)\n");
+ res = 2;
+ goto CLEANUP;
+ }
+
+ printf("Probably prime, 1 in 4^%d chance of false positive\n", g_tests);
+
+CLEANUP:
+ mp_clear(&a);
+
+ return res;
+}