1 files changed, 81 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/hcrypto/libtommath/etc/2kprime.c b/third_party/heimdal/lib/hcrypto/libtommath/etc/2kprime.c
new file mode 100644
index 0000000..95ed2de
--- /dev/null
+++ b/third_party/heimdal/lib/hcrypto/libtommath/etc/2kprime.c
@@ -0,0 +1,81 @@
+/* Makes safe primes of a 2k nature */
+#include <tommath.h>
+#include <time.h>
+
+static int sizes[] = {256, 512, 768, 1024, 1536, 2048, 3072, 4096};
+
+int main(void)
+{
+   char buf[2000];
+   size_t x;
+   mp_bool y;
+   mp_int q, p;
+   FILE *out;
+   clock_t t1;
+   mp_digit z;
+
+   mp_init_multi(&q, &p, NULL);
+
+   out = fopen("2kprime.1", "w");
+   if (out != NULL) {
+      for (x = 0; x < (sizeof(sizes) / sizeof(sizes[0])); x++) {
+top:
+         mp_2expt(&q, sizes[x]);
+         mp_add_d(&q, 3uL, &q);
+         z = -3;
+
+         t1 = clock();
+         for (;;) {
+            mp_sub_d(&q, 4uL, &q);
+            z += 4uL;
+
+            if (z > MP_MASK) {
+               printf("No primes of size %d found\n", sizes[x]);
+               break;
+            }
+
+            if ((clock() - t1) > CLOCKS_PER_SEC) {
+               printf(".");
+               fflush(stdout);
+               /*            sleep((clock() - t1 + CLOCKS_PER_SEC/2)/CLOCKS_PER_SEC); */
+               t1 = clock();
+            }
+
+            /* quick test on q */
+            mp_prime_is_prime(&q, 1, &y);
+            if (y == MP_NO) {
+               continue;
+            }
+
+            /* find (q-1)/2 */
+            mp_sub_d(&q, 1uL, &p);
+            mp_div_2(&p, &p);
+            mp_prime_is_prime(&p, 3, &y);
+            if (y == MP_NO) {
+               continue;
+            }
+
+            /* test on q */
+            mp_prime_is_prime(&q, 3, &y);
+            if (y == MP_NO) {
+               continue;
+            }
+
+            break;
+         }
+
+         if (y == MP_NO) {
+            ++sizes[x];
+            goto top;
+         }
+
+         mp_to_decimal(&q, buf, sizeof(buf));
+         printf("\n\n%d-bits (k = %lu) = %s\n", sizes[x], z, buf);
+         fprintf(out, "%d-bits (k = %lu) = %s\n", sizes[x], z, buf);
+         fflush(out);
+      }
+      fclose(out);
+   }
+
+   return 0;
+}