X-Git-Url: https://git.novaco.in/?p=novacoin.git;a=blobdiff_plain;f=src%2Fcrypter.h;h=dd5d50664af1ae5dde1363f33bdfab7ab71406b5;hp=5b95ea415e0359ec45838b6cd5331f2138780f46;hb=9acf270b14e561fe959ff25001f083a00e5e1caa;hpb=4e87d341f75f13bbd7d108c31c03886fbc4df56f

diff --git a/src/crypter.h b/src/crypter.h
index 5b95ea4..dd5d506 100644
--- a/src/crypter.h
+++ b/src/crypter.h
@@ -1,10 +1,12 @@
-// Copyright (c) 2011 The Bitcoin Developers
+// Copyright (c) 2009-2012 The Bitcoin Developers
 // Distributed under the MIT/X11 software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 #ifndef __CRYPTER_H__
 #define __CRYPTER_H__
 
+#include "allocators.h" /* for SecureString */
 #include "key.h"
+#include "serialize.h"
 
 const unsigned int WALLET_CRYPTO_KEY_SIZE = 32;
 const unsigned int WALLET_CRYPTO_SALT_SIZE = 8;
@@ -13,17 +15,18 @@ const unsigned int WALLET_CRYPTO_SALT_SIZE = 8;
 Private key encryption is done based on a CMasterKey,
 which holds a salt and random encryption key.
 
-CMasterKeys is encrypted using AES-256-CBC using a key
+CMasterKeys are encrypted using AES-256-CBC using a key
 derived using derivation method nDerivationMethod
 (0 == EVP_sha512()) and derivation iterations nDeriveIterations.
 vchOtherDerivationParameters is provided for alternative algorithms
 which may require more parameters (such as scrypt).
 
 Wallet Private Keys are then encrypted using AES-256-CBC
-with the double-sha256 of the private key as the IV, and the
-master key's key as the encryption key.
+with the double-sha256 of the public key as the IV, and the
+master key's key as the encryption key (see keystore.[ch]).
 */
 
+/** Master key for wallet encryption */
 class CMasterKey
 {
 public:
@@ -50,13 +53,34 @@ public:
         // 25000 rounds is just under 0.1 seconds on a 1.86 GHz Pentium M
         // ie slightly lower than the lowest hardware we need bother supporting
         nDeriveIterations = 25000;
-        nDerivationMethod = 0;
+        nDerivationMethod = 1;
         vchOtherDerivationParameters = std::vector<unsigned char>(0);
     }
+
+    CMasterKey(unsigned int nDerivationMethodIndex)
+    {
+        switch (nDerivationMethodIndex)
+        {
+            case 0: // sha512
+            default:
+                nDeriveIterations = 25000;
+                nDerivationMethod = 0;
+                vchOtherDerivationParameters = std::vector<unsigned char>(0);
+            break;
+
+            case 1: // scrypt+sha512
+                nDeriveIterations = 10000;
+                nDerivationMethod = 1;
+                vchOtherDerivationParameters = std::vector<unsigned char>(0);
+            break;
+        }
+    }
+
 };
 
 typedef std::vector<unsigned char, secure_allocator<unsigned char> > CKeyingMaterial;
 
+/** Encryption/decryption context with key information */
 class CCrypter
 {
 private:
@@ -65,7 +89,7 @@ private:
     bool fKeySet;
 
 public:
-    bool SetKeyFromPassphrase(const std::string &strKeyData, const std::vector<unsigned char>& chSalt, const unsigned int nRounds, const unsigned int nDerivationMethod);
+    bool SetKeyFromPassphrase(const SecureString &strKeyData, const std::vector<unsigned char>& chSalt, const unsigned int nRounds, const unsigned int nDerivationMethod);
     bool Encrypt(const CKeyingMaterial& vchPlaintext, std::vector<unsigned char> &vchCiphertext);
     bool Decrypt(const std::vector<unsigned char>& vchCiphertext, CKeyingMaterial& vchPlaintext);
     bool SetKey(const CKeyingMaterial& chNewKey, const std::vector<unsigned char>& chNewIV);
@@ -74,19 +98,26 @@ public:
     {
         memset(&chKey, 0, sizeof chKey);
         memset(&chIV, 0, sizeof chIV);
-        munlock(&chKey, sizeof chKey);
-        munlock(&chIV, sizeof chIV);
         fKeySet = false;
     }
 
     CCrypter()
     {
         fKeySet = false;
+
+        // Try to keep the key data out of swap (and be a bit over-careful to keep the IV that we don't even use out of swap)
+        // Note that this does nothing about suspend-to-disk (which will put all our key data on disk)
+        // Note as well that at no point in this program is any attempt made to prevent stealing of keys by reading the memory of the running process.
+        LockedPageManager::instance.LockRange(&chKey[0], sizeof chKey);
+        LockedPageManager::instance.LockRange(&chIV[0], sizeof chIV);
     }
 
     ~CCrypter()
     {
         CleanKey();
+
+        LockedPageManager::instance.UnlockRange(&chKey[0], sizeof chKey);
+        LockedPageManager::instance.UnlockRange(&chIV[0], sizeof chIV);
     }
 };