From: Pauli <pauli@openssl.org>
Date: Thu, 27 Jan 2022 04:05:48 +0000 (+1100)
Subject: aes: make the no-asm constant time code path not the default
X-Git-Tag: openssl-3.2.0-alpha1~3006
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e180bf641ed23010073b0882d63d5dfd48409602;p=thirdparty%2Fopenssl.git

aes: make the no-asm constant time code path not the default

After OMC and OTC discussions, the 95% performance loss resulting from
the constant time code was deemed excessive for something outside of
our security policy.

The option to use the constant time code exists as it was in OpenSSL 1.1.1.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17600)
---

diff --git a/CHANGES.md b/CHANGES.md
index a542e253749..3799c28c97f 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -90,6 +90,15 @@ breaking changes, and mappings for the large list of deprecated functions.
 
 [Migration guide]: https://github.com/openssl/openssl/tree/master/doc/man7/migration_guide.pod
 
+### Changes between 3.0.1 and 3.0.2 [xx XXX xxxx]
+
+ * Made the AES constant time code for no-asm configurations
+   optional due to the resulting 95% performance degradation.
+   The AES constant time code can be enabled, for no assembly
+   builds, with: ./config no-asm -DOPENSSL_AES_CONST_TIME
+
+   *Paul Dale*
+
 ### Changes between 3.0.0 and 3.0.1 [14 dec 2021]
 
  * Fixed invalid handling of X509_verify_cert() internal errors in libssl
diff --git a/crypto/aes/aes_core.c b/crypto/aes/aes_core.c
index 7b9989fd470..d3eaab349f4 100644
--- a/crypto/aes/aes_core.c
+++ b/crypto/aes/aes_core.c
@@ -50,7 +50,7 @@
 #include <openssl/aes.h>
 #include "aes_local.h"
 
-#if !defined(OPENSSL_NO_AES_CONST_TIME) && !defined(AES_ASM)
+#if defined(OPENSSL_AES_CONST_TIME) && !defined(AES_ASM)
 
 # if (defined(_WIN32) || defined(_WIN64)) && !defined(__MINGW32__)
 #  define U64(C) C##UI64