From 18a2c79d848ce45e8fbd3707a5b8db0b70a5ce33 Mon Sep 17 00:00:00 2001
From: iamunick <why@iamunick.com>
Date: Tue, 20 May 2014 14:12:40 -0400
Subject: [PATCH] use openssl_cleanse instead of memset for crit mem spaces

---
 src/allocators.h | 5 +++--
 src/base58.h     | 2 +-
 src/crypter.cpp  | 4 ++--
 src/crypter.h    | 4 ++--
 src/util.cpp     | 2 +-
 5 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/allocators.h b/src/allocators.h
index 99afa10..eb2aed6 100644
--- a/src/allocators.h
+++ b/src/allocators.h
@@ -9,6 +9,7 @@
 #include <string>
 #include <boost/thread/mutex.hpp>
 #include <map>
+#include <openssl/crypto.h> // for OPENSSL_cleanse()
 
 #ifdef WIN32
 #ifdef _WIN32_WINNT
@@ -212,7 +213,7 @@ struct secure_allocator : public std::allocator<T>
     {
         if (p != NULL)
         {
-            memset(p, 0, sizeof(T) * n);
+            OPENSSL_cleanse(p, sizeof(T) * n);
             LockedPageManager::instance.UnlockRange(p, sizeof(T) * n);
         }
         std::allocator<T>::deallocate(p, n);
@@ -246,7 +247,7 @@ struct zero_after_free_allocator : public std::allocator<T>
     void deallocate(T* p, std::size_t n)
     {
         if (p != NULL)
-            memset(p, 0, sizeof(T) * n);
+            OPENSSL_cleanse(p, sizeof(T) * n);
         std::allocator<T>::deallocate(p, n);
     }
 };
diff --git a/src/base58.h b/src/base58.h
index 969d6a7..5865d9f 100644
--- a/src/base58.h
+++ b/src/base58.h
@@ -221,7 +221,7 @@ class CBase58Data
         vchData.resize(vchTemp.size() - 1);
         if (!vchData.empty())
             memcpy(&vchData[0], &vchTemp[1], vchData.size());
-        memset(&vchTemp[0], 0, vchTemp.size());
+        OPENSSL_cleanse(&vchTemp[0], vchData.size());
         return true;
     }
 
diff --git a/src/crypter.cpp b/src/crypter.cpp
index 181b8fa..a2b62a8 100644
--- a/src/crypter.cpp
+++ b/src/crypter.cpp
@@ -24,8 +24,8 @@ bool CCrypter::SetKeyFromPassphrase(const SecureString& strKeyData, const std::v
 
     if (i != (int)WALLET_CRYPTO_KEY_SIZE)
     {
-        memset(&chKey, 0, sizeof chKey);
-        memset(&chIV, 0, sizeof chIV);
+        OPENSSL_cleanse(chKey, sizeof(chKey));
+        OPENSSL_cleanse(chIV, sizeof(chIV));
         return false;
     }
 
diff --git a/src/crypter.h b/src/crypter.h
index 04538a3..6f75170 100644
--- a/src/crypter.h
+++ b/src/crypter.h
@@ -76,8 +76,8 @@ class CCrypter
 
     void CleanKey()
     {
-        memset(&chKey, 0, sizeof chKey);
-        memset(&chIV, 0, sizeof chIV);
+        OPENSSL_cleanse(chKey, sizeof(chKey));
+        OPENSSL_cleanse(chIV, sizeof(chIV));
         fKeySet = false;
     }
 
diff --git a/src/util.cpp b/src/util.cpp
index 21bb817..c3c42f8 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -160,7 +160,7 @@ void RandAddSeedPerfmon()
     if (ret == ERROR_SUCCESS)
     {
         RAND_add(pdata, nSize, nSize/100.0);
-        memset(pdata, 0, nSize);
+        OPENSSL_cleanse(pdata, nSize);
         printf("RandAddSeed() %lu bytes\n", nSize);
     }
 #endif