1 files changed, 67 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/hcrypto/libtommath/etc/drprime.c b/third_party/heimdal/lib/hcrypto/libtommath/etc/drprime.c
new file mode 100644
index 00000000000..64e31ef1046
--- /dev/null
+++ b/third_party/heimdal/lib/hcrypto/libtommath/etc/drprime.c
@@ -0,0 +1,67 @@
+/* Makes safe primes of a DR nature */
+#include <tommath.h>
+
+static int sizes[] = { 1+256/MP_DIGIT_BIT, 1+512/MP_DIGIT_BIT, 1+768/MP_DIGIT_BIT, 1+1024/MP_DIGIT_BIT, 1+2048/MP_DIGIT_BIT, 1+4096/MP_DIGIT_BIT };
+
+int main(void)
+{
+   mp_bool res;
+   int x, y;
+   char buf[4096];
+   FILE *out;
+   mp_int a, b;
+
+   mp_init(&a);
+   mp_init(&b);
+
+   out = fopen("drprimes.txt", "w");
+   if (out != NULL) {
+      for (x = 0; x < (int)(sizeof(sizes)/sizeof(sizes[0])); x++) {
+top:
+         printf("Seeking a %d-bit safe prime\n", sizes[x] * MP_DIGIT_BIT);
+         mp_grow(&a, sizes[x]);
+         mp_zero(&a);
+         for (y = 1; y < sizes[x]; y++) {
+            a.dp[y] = MP_MASK;
+         }
+
+         /* make a DR modulus */
+         a.dp[0] = -1;
+         a.used = sizes[x];
+
+         /* now loop */
+         res = MP_NO;
+         for (;;) {
+            a.dp[0] += 4uL;
+            if (a.dp[0] >= MP_MASK) break;
+            mp_prime_is_prime(&a, 1, &res);
+            if (res == MP_NO) continue;
+            printf(".");
+            fflush(stdout);
+            mp_sub_d(&a, 1uL, &b);
+            mp_div_2(&b, &b);
+            mp_prime_is_prime(&b, 3, &res);
+            if (res == MP_NO) continue;
+            mp_prime_is_prime(&a, 3, &res);
+            if (res == MP_YES) break;
+         }
+
+         if (res != MP_YES) {
+            printf("Error not DR modulus\n");
+            sizes[x] += 1;
+            goto top;
+         } else {
+            mp_to_decimal(&a, buf, sizeof(buf));
+            printf("\n\np == %s\n\n", buf);
+            fprintf(out, "%d-bit prime:\np == %s\n\n", mp_count_bits(&a), buf);
+            fflush(out);
+         }
+      }
+      fclose(out);
+   }
+
+   mp_clear(&a);
+   mp_clear(&b);
+
+   return 0;
+}