Change bn_expand()/bn_wexpand() to indicate failure/success via 0/1.

Currently bn_expand()/bn_wexpand() return a BIGNUM *, however none of the
callers use this (and many already treat it as a true/false value).
Change these functions to return 0 on failure and 1 on success, revising
callers that test against NULL in the process.

ok tb@

1 files changed, 2 insertions, 2 deletions

diff --git a/src/lib/libcrypto/bn/bn_exp.c b/src/lib/libcrypto/bn/bn_exp.c
index 3525b50388..64156f716f 100644
--- a/src/lib/libcrypto/bn/bn_exp.c
+++ b/src/lib/libcrypto/bn/bn_exp.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bn_exp.c,v 1.32 2022/04/20 13:32:34 tb Exp $ */
+/* $OpenBSD: bn_exp.c,v 1.33 2022/11/24 01:30:01 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -590,7 +590,7 @@ MOD_EXP_CTIME_COPY_FROM_PREBUF(BIGNUM *b, int top, unsigned char *buf, int idx,
         int width = 1 << window;
         volatile BN_ULONG *table = (volatile BN_ULONG *)buf;
 
-        if (bn_wexpand(b, top) == NULL)
+        if (!bn_wexpand(b, top))
                 return 0;
 
         if (window <= 3) {