ec_mont_group_set_curve: convert to BN_MONT_CTX_create() and simplify

This removes the penultimate internal call of BN_MONT_CTX_new(). The last
one could be removed at the cost of introducing a BN_MONT_CTX_dup(), which
probably isn't worth it.

ok jsing

1 files changed, 7 insertions, 20 deletions

diff --git a/src/lib/libcrypto/ec/ecp_methods.c b/src/lib/libcrypto/ec/ecp_methods.c
index ad975cb646..d1d0add538 100644
--- a/src/lib/libcrypto/ec/ecp_methods.c
+++ b/src/lib/libcrypto/ec/ecp_methods.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ecp_methods.c,v 1.42 2025/01/25 13:15:21 tb Exp $ */
+/* $OpenBSD: ecp_methods.c,v 1.43 2025/02/13 11:19:49 tb Exp $ */
 /* Includes code written by Lenka Fibikova <fibikova@exp-math.uni-essen.de>
  * for the OpenSSL project.
  * Includes code written by Bodo Moeller for the OpenSSL project.
@@ -1217,33 +1217,20 @@ static int
 ec_mont_group_set_curve(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
     const BIGNUM *b, BN_CTX *ctx)
 {
-        BN_MONT_CTX *mont = NULL;
-        int ret = 0;
-
         BN_MONT_CTX_free(group->mont_ctx);
-        group->mont_ctx = NULL;
-
-        if ((mont = BN_MONT_CTX_new()) == NULL)
+        if ((group->mont_ctx = BN_MONT_CTX_create(p, ctx)) == NULL)
                 goto err;
-        if (!BN_MONT_CTX_set(mont, p, ctx)) {
-                ECerror(ERR_R_BN_LIB);
-                goto err;
-        }
-        group->mont_ctx = mont;
-        mont = NULL;
 
-        if (!ec_group_set_curve(group, p, a, b, ctx)) {
-                BN_MONT_CTX_free(group->mont_ctx);
-                group->mont_ctx = NULL;
+        if (!ec_group_set_curve(group, p, a, b, ctx))
                 goto err;
-        }
 
-        ret = 1;
+        return 1;
 
  err:
-        BN_MONT_CTX_free(mont);
+        BN_MONT_CTX_free(group->mont_ctx);
+        group->mont_ctx = NULL;
 
-        return ret;
+        return 0;
 }
 
 static int