commit d224d52aba4b73fce82f8b703d6d6f0202da4391
author David Benjamin <davidben@google.com> Tue Aug 16 10:03:45 2016 -0400
committer CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org> Thu Aug 18 18:18:31 2016 +0000
tree 5115a2d37ee270a036d0fcd1438037fb7dcbc122
parent 8fcc755cf5a39149e135e561cb8349c513b5ae05

Add constants for BN_rand and use them.

See upstream's f67cbb74437842a0f88f84f43a0faa968ca77b35 and
2301d91dd58d9827865e360d616291f2549ec5bf.

Change-Id: I3b79323847a7610143a9dfb9b5b45bf7a33d8690
Reviewed-on: https://boringssl-review.googlesource.com/10369
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

include/openssl/bn.h

diff --git a/include/openssl/bn.h b/include/openssl/bn.h
index ff9d680..f84362d 100644
--- a/include/openssl/bn.h
+++ b/include/openssl/bn.h
@@ -577,15 +577,27 @@
 
 /* Random and prime number generation. */
 
-/* BN_rand sets |rnd| to a random number of length |bits|. If |top| is zero, the
- * most-significant bit, if any, will be set. If |top| is one, the two most
- * significant bits, if any, will be set.
+/* The following are values for the |top| parameter of |BN_rand|. */
+#define BN_RAND_TOP_ANY    -1
+#define BN_RAND_TOP_ONE     0
+#define BN_RAND_TOP_TWO     1
+
+/* The following are values for the |bottom| parameter of |BN_rand|. */
+#define BN_RAND_BOTTOM_ANY  0
+#define BN_RAND_BOTTOM_ODD  1
+
+/* BN_rand sets |rnd| to a random number of length |bits|. It returns one on
+ * success and zero otherwise.
  *
- * If |top| is -1 then no extra action will be taken and |BN_num_bits(rnd)| may
- * not equal |bits| if the most significant bits randomly ended up as zeros.
+ * |top| must be one of the |BN_RAND_TOP_*| values. If |BN_RAND_TOP_ONE|, the
+ * most-significant bit, if any, will be set. If |BN_RAND_TOP_TWO|, the two
+ * most significant bits, if any, will be set. If |BN_RAND_TOP_ANY|, no extra
+ * action will be taken and |BN_num_bits(rnd)| may not equal |bits| if the most
+ * significant bits randomly ended up as zeros.
  *
- * If |bottom| is non-zero, the least-significant bit, if any, will be set. The
- * function returns one on success or zero otherwise. */
+ * |bottom| must be one of the |BN_RAND_BOTTOM_*| values. If
+ * |BN_RAND_BOTTOM_ODD|, the least-significant bit, if any, will be set. If
+ * |BN_RAND_BOTTOM_ANY|, no extra action will be taken. */
 OPENSSL_EXPORT int BN_rand(BIGNUM *rnd, int bits, int top, int bottom);
 
 /* BN_pseudo_rand is an alias for |BN_rand|. */