VeraCrypt
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+/*
+ Legal Notice: Some portions of the source code contained in this file were
+ derived from the source code of Encryption for the Masses 2.02a, which is
+ Copyright (c) 1998-2000 Paul Le Roux and which is governed by the 'License
+ Agreement for Encryption for the Masses'. Modifications and additions to
+ the original source code (contained in this file) and all other portions
+ of this file are Copyright (c) 2003-2008 TrueCrypt Developers Association
+ and are governed by the TrueCrypt License 3.0 the full text of which is
+ contained in the file License.txt included in TrueCrypt binary and source
+ code distribution packages. */
+
+#include "Tcdefs.h"
+#include "Crypto.h"
+#include "Fat.h"
+#include "Volumes.h"
+#include "Apidrvr.h"
+#include "Common.h"
+#include "Cache.h"
+
+Password CachedPasswords[CACHE_SIZE];
+int cacheEmpty = 1;
+static int nPasswordIdx = 0;
+
+int ReadVolumeHeaderWCache (BOOL bBoot, BOOL bCache, char *header, Password *password, PCRYPTO_INFO *retInfo)
+{
+ int nReturnCode = ERR_PASSWORD_WRONG;
+ int i;
+
+ /* Attempt to recognize volume using mount password */
+ if (password->Length > 0)
+ {
+ nReturnCode = ReadVolumeHeader (bBoot, header, password, retInfo, NULL);
+
+ /* Save mount passwords back into cache if asked to do so */
+ if (bCache && (nReturnCode == 0 || nReturnCode == ERR_CIPHER_INIT_WEAK_KEY))
+ {
+ for (i = 0; i < CACHE_SIZE; i++)
+ {
+ if (memcmp (&CachedPasswords[i], password, sizeof (Password)) == 0)
+ break;
+ }
+
+ if (i == CACHE_SIZE)
+ {
+ /* Store the password */
+ CachedPasswords[nPasswordIdx] = *password;
+
+ /* Try another slot */
+ nPasswordIdx = (nPasswordIdx + 1) % CACHE_SIZE;
+
+ cacheEmpty = 0;
+ }
+ }
+ }
+ else if (!cacheEmpty)
+ {
+ /* Attempt to recognize volume using cached passwords */
+ for (i = 0; i < CACHE_SIZE; i++)
+ {
+ if (CachedPasswords[i].Length > 0)
+ {
+ nReturnCode = ReadVolumeHeader (bBoot, header, &CachedPasswords[i], retInfo, NULL);
+
+ if (nReturnCode != ERR_PASSWORD_WRONG)
+ break;
+ }
+ }
+ }
+
+ return nReturnCode;
+}
+
+
+void AddPasswordToCache (Password *password)
+{
+ int i;
+ for (i = 0; i < CACHE_SIZE; i++)
+ {
+ if (memcmp (&CachedPasswords[i], password, sizeof (Password)) == 0)
+ return;
+ }
+
+ CachedPasswords[nPasswordIdx] = *password;
+ nPasswordIdx = (nPasswordIdx + 1) % CACHE_SIZE;
+ cacheEmpty = 0;
+}
+
+
+void WipeCache ()
+{
+ burn (CachedPasswords, sizeof (CachedPasswords));
+ nPasswordIdx = 0;
+ cacheEmpty = 1;
+}