Make BN_BLINDING internal

RSA is pretty bad. In my most optimistic moments I dream of a world that
stopped using it. That won't happen during my lifetime, unfortunately.
Blinding is one way of making it a little less leaky. Unfortunately this
side-channel leak mitigation leaked out of the library for no good reason.
Let's at least fix that aspect of it.

ok jsing

1 files changed, 3 insertions, 1 deletions

diff --git a/src/lib/libcrypto/rsa/rsa_local.h b/src/lib/libcrypto/rsa/rsa_local.h
index b4e90abd94..e4c3040b6f 100644
--- a/src/lib/libcrypto/rsa/rsa_local.h
+++ b/src/lib/libcrypto/rsa/rsa_local.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: rsa_local.h,v 1.3 2023/07/21 15:26:51 tb Exp $ */
+/* $OpenBSD: rsa_local.h,v 1.4 2023/07/28 10:05:16 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -153,4 +153,6 @@ int RSA_padding_check_X931(unsigned char *to, int tlen,
     const unsigned char *f, int fl, int rsa_len);
 int RSA_X931_hash_id(int nid);
 
+BN_BLINDING *RSA_setup_blinding(RSA *rsa, BN_CTX *ctx);
+
 __END_HIDDEN_DECLS