Add a second test to validate the tables in the library.

1 files changed, 42 insertions, 1 deletions

diff --git a/src/regress/lib/libcrypto/bn/general/bn_isqrt.c b/src/regress/lib/libcrypto/bn/general/bn_isqrt.c
index 8c932be265..3ada3d9edf 100644
--- a/src/regress/lib/libcrypto/bn/general/bn_isqrt.c
+++ b/src/regress/lib/libcrypto/bn/general/bn_isqrt.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: bn_isqrt.c,v 1.3 2022/07/27 19:22:45 tb Exp $ */
+/*      $OpenBSD: bn_isqrt.c,v 1.4 2022/07/28 20:06:01 tb Exp $ */
 /*
  * Copyright (c) 2022 Theo Buehler <tb@openbsd.org>
  *
@@ -116,6 +116,46 @@ check_tables(int print)
         return failed;
 }
 
+static int
+validate_tables(void)
+{
+        int fill[] = {11, 63, 64, 65};
+        const uint8_t *table;
+        size_t i;
+        int j, k;
+        int failed = 0;
+
+        for (i = 0; i < sizeof(fill) / sizeof(fill[0]); i++) {
+                if ((table = get_table(fill[i])) == NULL) {
+                        fprintf(stderr, "failed to get table %d\n", fill[i]);
+                        failed |= 1;
+                        continue;
+                }
+
+                for (j = 0; j < fill[i]; j++) {
+                        for (k = 0; k < fill[i]; k++) {
+                                if (j == (k * k) % fill[i])
+                                        break;
+                        }
+
+                        if (table[j] == 0 && k < fill[i]) {
+                                fprintf(stderr, "%d == %d^2 (mod %d)", j, k,
+                                    fill[i]);
+                                failed |= 1;
+                        }
+                        if (table[j] == 1 && k == fill[i]) {
+                                fprintf(stderr, "%d not a square (mod %d)", j,
+                                    fill[i]);
+                                failed |= 1;
+                        }
+
+                }
+
+        }
+
+        return failed;
+}
+
 /*
  * Choose a random number n of bit length between LOWER_BITS and UPPER_BITS and
  * check that n == isqrt(n^2). Random numbers n^2 <= test < (n + 1)^2 are
@@ -282,6 +322,7 @@ main(int argc, char *argv[])
                 failed |= isqrt_test();
 
         failed |= check_tables(0);
+        failed |= validate_tables();
 
         if (!failed)
                 printf("SUCCESS\n");