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, 5 insertions, 5 deletions

diff --git a/src/lib/libcrypto/bn/bn_mont.c b/src/lib/libcrypto/bn/bn_mont.c
index 4555f6146b..251c67b89d 100644
--- a/src/lib/libcrypto/bn/bn_mont.c
+++ b/src/lib/libcrypto/bn/bn_mont.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bn_mont.c,v 1.29 2022/11/23 03:10:10 jsing Exp $ */
+/* $OpenBSD: bn_mont.c,v 1.30 2022/11/24 01:30:01 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -137,7 +137,7 @@ BN_mod_mul_montgomery(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
         int num = mont->N.top;
 
         if (num > 1 && a->top == num && b->top == num) {
-                if (bn_wexpand(r, num) == NULL)
+                if (!bn_wexpand(r, num))
                         return (0);
                 if (bn_mul_mont(r->d, a->d, b->d, mont->N.d, mont->n0, num)) {
                         r->neg = a->neg^b->neg;
@@ -197,7 +197,7 @@ BN_from_montgomery_word(BIGNUM *ret, BIGNUM *r, BN_MONT_CTX *mont)
         }
 
         max = (2 * nl); /* carry is stored separately */
-        if (bn_wexpand(r, max) == NULL)
+        if (!bn_wexpand(r, max))
                 return (0);
 
         r->neg ^= n->neg;
@@ -226,7 +226,7 @@ BN_from_montgomery_word(BIGNUM *ret, BIGNUM *r, BN_MONT_CTX *mont)
                 rp[nl] = v;
         }
 
-        if (bn_wexpand(ret, nl) == NULL)
+        if (!bn_wexpand(ret, nl))
                 return (0);
         ret->top = nl;
         ret->neg = r->neg;
@@ -419,7 +419,7 @@ BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)
                 }
                 else /* if N mod word size == 1 */
                 {
-                        if (bn_wexpand(Ri, 2) == NULL)
+                        if (!bn_wexpand(Ri, 2))
                                 goto err;
                         /* Ri-- (mod double word size) */
                         Ri->neg = 0;