Add regress coverage for BN_num_bits()

1 files changed, 35 insertions, 1 deletions

diff --git a/src/regress/lib/libcrypto/bn/bn_unit.c b/src/regress/lib/libcrypto/bn/bn_unit.c
index 95764dfce1..24c7569ff9 100644
--- a/src/regress/lib/libcrypto/bn/bn_unit.c
+++ b/src/regress/lib/libcrypto/bn/bn_unit.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: bn_unit.c,v 1.4 2023/03/31 19:40:08 tb Exp $ */
+/*      $OpenBSD: bn_unit.c,v 1.5 2023/06/20 06:36:09 jsing Exp $ */
 
 /*
  * Copyright (c) 2022 Theo Buehler <tb@openbsd.org>
@@ -70,6 +70,39 @@ test_bn_print_null_derefs(void)
 }
 
 static int
+test_bn_num_bits(void)
+{
+        BIGNUM *bn;
+        int i, num_bits;
+        int failed = 0;
+
+        if ((bn = BN_new()) == NULL)
+                errx(1, "BN_new");
+
+        if ((num_bits = BN_num_bits(bn)) != 0) {
+                warnx("BN_num_bits_word(0): want 0, got %d", num_bits);
+                failed |= 1;
+        }
+
+        if (!BN_set_word(bn, 1))
+                errx(1, "BN_set_word");
+
+        for (i = 0; i <= 5 * BN_BITS2; i++) {
+                if ((num_bits = BN_num_bits(bn)) != i + 1) {
+                        warnx("BN_num_bits(1 << %d): want %d, got %d",
+                            i, i + 1, num_bits);
+                        failed |= 1;
+                }
+                if (!BN_lshift1(bn, bn))
+                        errx(1, "BN_lshift1");
+        }
+
+        BN_free(bn);
+
+        return failed;
+}
+
+static int
 test_bn_num_bits_word(void)
 {
         BN_ULONG w = 1;
@@ -255,6 +288,7 @@ main(void)
         int failed = 0;
 
         failed |= test_bn_print_null_derefs();
+        failed |= test_bn_num_bits();
         failed |= test_bn_num_bits_word();
         failed |= test_bn_copy_copies_flags();
         failed |= test_bn_copy_consttime_is_sticky();