Use the libgcrypt SALSA20 cipher if available.

CMakeLists.txt

@@ -167,6 +167,10 @@ find_package(Qt4 4.6.0 REQUIRED ${QT_REQUIRED_MODULES})
 include(${QT_USE_FILE})
 
 find_package(Gcrypt REQUIRED)
+if(NOT (${GCRYPT_VERSION_STRING} VERSION_LESS "1.6.0"))
+  message(STATUS "Gcrypt ${GCRYPT_VERSION_STRING} supports the SALSA20 cipher")
+  set(GCRYPT_HAS_SALSA20 1)
+endif()
 
 find_package(ZLIB REQUIRED)
 

src/CMakeLists.txt

@@ -53,15 +53,9 @@ set(keepassx_SOURCES
     crypto/Crypto.cpp
     crypto/CryptoHash.cpp
     crypto/Random.cpp
-    crypto/salsa20/ecrypt-config.h
-    crypto/salsa20/ecrypt-machine.h
-    crypto/salsa20/ecrypt-portable.h
-    crypto/salsa20/ecrypt-sync.h
-    crypto/salsa20/salsa20.c
     crypto/SymmetricCipher.cpp
     crypto/SymmetricCipherBackend.h
     crypto/SymmetricCipherGcrypt.cpp
-    crypto/SymmetricCipherSalsa20.cpp
     format/KeePass1.h
     format/KeePass1Reader.cpp
     format/KeePass2.h
@@ -117,6 +111,18 @@ set(keepassx_SOURCES
     streams/SymmetricCipherStream.cpp
 )
 
+if(NOT GCRYPT_HAS_SALSA20)
+  set(keepassx_SOURCES
+      ${keepassx_SOURCES}
+      crypto/salsa20/ecrypt-config.h
+      crypto/salsa20/ecrypt-machine.h
+      crypto/salsa20/ecrypt-portable.h
+      crypto/salsa20/ecrypt-sync.h
+      crypto/salsa20/salsa20.c
+      crypto/SymmetricCipherSalsa20.cpp
+  )
+endif()
+
 set(keepassx_SOURCES_MAINEXE
     main.cpp
 )

src/config-keepassx.h.cmake

@@ -13,4 +13,6 @@
 #cmakedefine HAVE_RLIMIT_CORE 1
 #cmakedefine HAVE_PT_DENY_ATTACH 1
 
+#cmakedefine GCRYPT_HAS_SALSA20
+
 #endif // KEEPASSX_CONFIG_H

src/crypto/SymmetricCipher.cpp

@@ -17,6 +17,7 @@
 
 #include "SymmetricCipher.h"
 
+#include "config-keepassx.h"
 #include "crypto/SymmetricCipherGcrypt.h"
 #include "crypto/SymmetricCipherSalsa20.h"
 
@@ -39,10 +40,15 @@ SymmetricCipherBackend* SymmetricCipher::createBackend(SymmetricCipher::Algorith
     switch (algo) {
     case SymmetricCipher::Aes256:
     case SymmetricCipher::Twofish:
+#if defined(GCRYPT_HAS_SALSA20)
+    case SymmetricCipher::Salsa20:
+#endif
         return new SymmetricCipherGcrypt(algo, mode, direction);
 
+#if !defined(GCRYPT_HAS_SALSA20)
     case SymmetricCipher::Salsa20:
         return new SymmetricCipherSalsa20(algo, mode, direction);
+#endif
 
     default:
         Q_ASSERT(false);

src/crypto/SymmetricCipherGcrypt.cpp

@@ -17,6 +17,7 @@
 
 #include "SymmetricCipherGcrypt.h"
 
+#include "config-keepassx.h"
 #include "crypto/Crypto.h"
 
 SymmetricCipherGcrypt::SymmetricCipherGcrypt(SymmetricCipher::Algorithm algo, SymmetricCipher::Mode mode,
@@ -43,6 +44,11 @@ int SymmetricCipherGcrypt::gcryptAlgo(SymmetricCipher::Algorithm algo)
     case SymmetricCipher::Twofish:
         return GCRY_CIPHER_TWOFISH;
 
+#ifdef GCRYPT_HAS_SALSA20
+    case SymmetricCipher::Salsa20:
+        return GCRY_CIPHER_SALSA20;
+#endif
+
     default:
         Q_ASSERT(false);
         return -1;
@@ -58,6 +64,9 @@ int SymmetricCipherGcrypt::gcryptMode(SymmetricCipher::Mode mode)
     case SymmetricCipher::Cbc:
         return GCRY_CIPHER_MODE_CBC;
 
+    case SymmetricCipher::Stream:
+        return GCRY_CIPHER_MODE_STREAM;
+
     default:
         Q_ASSERT(false);
         return -1;