From 74aef213fe7971cc5374b46f9129f281fa6ee456 Mon Sep 17 00:00:00 2001
From: moneromooo-monero <moneromooo-monero@users.noreply.github.com>
Date: Tue, 9 Feb 2016 09:29:12 +0000
Subject: [PATCH 1/2] crypto: use software AES based on the
 MONERO_USE_SOFTWARE_AES env var

Setting to no or 0 also works. If set, any other value enables it.

Useful for running with valgrind in cases where it fails at
properly implementing AES-NI.
---
 src/crypto/slow-hash.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/crypto/slow-hash.c b/src/crypto/slow-hash.c
index 903a3792..faaf127c 100644
--- a/src/crypto/slow-hash.c
+++ b/src/crypto/slow-hash.c
@@ -187,6 +187,16 @@ STATIC INLINE void xor_blocks(uint8_t *a, const uint8_t *b)
  * @return true if the CPU supports AES, false otherwise
  */
 
+STATIC INLINE int force_software_aes(void)
+{
+  const char *env = getenv("MONERO_USE_SOFTWARE_AES");
+  if (!env)
+    return 0;
+  if (!strcmp(env, "0") || !strcmp(env, "no"))
+    return 0;
+  return 1;
+}
+
 STATIC INLINE int check_aes_hw(void)
 {
     int cpuid_results[4];
@@ -509,7 +519,7 @@ void cn_slow_hash(const void *data, size_t length, char *hash)
     size_t i, j;
     uint64_t *p = NULL;
     oaes_ctx *aes_ctx;
-    int useAes = check_aes_hw();
+    int useAes = !force_software_aes() && check_aes_hw();
 
     static void (*const extra_hashes[4])(const void *, size_t, char *) =
     {

From c7e6b7739565951b06be42997bd97415faf35d4e Mon Sep 17 00:00:00 2001
From: moneromooo-monero <moneromooo-monero@users.noreply.github.com>
Date: Tue, 9 Feb 2016 09:38:17 +0000
Subject: [PATCH 2/2] crypto: only check MONERO_USE_SOFTWARE_AES once

---
 src/crypto/slow-hash.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/crypto/slow-hash.c b/src/crypto/slow-hash.c
index faaf127c..4efa8af6 100644
--- a/src/crypto/slow-hash.c
+++ b/src/crypto/slow-hash.c
@@ -189,12 +189,22 @@ STATIC INLINE void xor_blocks(uint8_t *a, const uint8_t *b)
 
 STATIC INLINE int force_software_aes(void)
 {
+  static int use = -1;
+
+  if (use != -1)
+    return use;
+
   const char *env = getenv("MONERO_USE_SOFTWARE_AES");
-  if (!env)
-    return 0;
-  if (!strcmp(env, "0") || !strcmp(env, "no"))
-    return 0;
-  return 1;
+  if (!env) {
+    use = 0;
+  }
+  else if (!strcmp(env, "0") || !strcmp(env, "no")) {
+    use = 0;
+  }
+  else {
+    use = 1;
+  }
+  return use;
 }
 
 STATIC INLINE int check_aes_hw(void)