From b713c4fff76d84eb67436045b46cc775f40deb47 Mon Sep 17 00:00:00 2001
From: Rich Salz
Date: Mon, 22 Jan 2018 14:41:09 -0500
Subject: [PATCH] Improve some BN documentation.
Thanks to Nicolas Schodet for pointing this out.
Reviewed-by: Tim Hudson
(Merged from https://github.com/openssl/openssl/pull/5141)
---
doc/man3/BN_zero.pod | 23 ++++++++++++++---------
1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/doc/man3/BN_zero.pod b/doc/man3/BN_zero.pod
index 167a7e4cec..1d7744bf2a 100644
--- a/doc/man3/BN_zero.pod
+++ b/doc/man3/BN_zero.pod
@@ -14,24 +14,26 @@ operations
const BIGNUM *BN_value_one(void);
- int BN_set_word(BIGNUM *a, unsigned long w);
- unsigned long BN_get_word(BIGNUM *a);
+ int BN_set_word(BIGNUM *a, BN_ULONG w);
+ unsigned BN_ULONG BN_get_word(BIGNUM *a);
=head1 DESCRIPTION
+B is a macro that will be an unsigned integral type optimized
+for the most efficient implementation on the local platform.
+
BN_zero(), BN_one() and BN_set_word() set B to the values 0, 1 and
B respectively. BN_zero() and BN_one() are macros.
BN_value_one() returns a B constant of value 1. This constant
is useful for use in comparisons and assignment.
-BN_get_word() returns B, if it can be represented as an unsigned
-long.
+BN_get_word() returns B, if it can be represented as a B.
=head1 RETURN VALUES
-BN_get_word() returns the value B, and 0xffffffffL if B cannot
-be represented as an unsigned long.
+BN_get_word() returns the value B, or all-bits-set if B cannot
+be represented as a single integer.
BN_one() and BN_set_word() return 1 on success, 0 otherwise.
BN_value_one() returns the constant.
@@ -39,8 +41,11 @@ BN_zero() never fails and returns no value.
=head1 BUGS
-If a B is equal to 0xffffffffL it can be represented as an
-unsigned long but this value is also returned on error.
+If a B is equal to the value of all-bits-set, it will collide
+with the error condition returned by BN_get_word() which uses that
+as an error value.
+
+B should probably be a typedef.
=head1 SEE ALSO
@@ -53,7 +58,7 @@ versions returned an int.
=head1 COPYRIGHT
-Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the OpenSSL license (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
--
2.17.1