Implements KDBX4 format with Argon2 KDF

* Adds KDBX4 reader/writer interfaces
* Adds KDBX4 XML reader/write interfaces
* Implements test cases for KDBX4
* Fully compatible with KeePass2
* Corrects minor issues with Argon2 KDF

1 files changed, 46 insertions, 0 deletions

diff --git a/src/format/KeePass2.cpp b/src/format/KeePass2.cpp
index fd57148d0..f89e828a1 100644
--- a/src/format/KeePass2.cpp
+++ b/src/format/KeePass2.cpp
@@ -19,6 +19,7 @@
 #include <QSharedPointer>
 #include "crypto/kdf/AesKdf.h"
 #include "crypto/kdf/Argon2Kdf.h"
+#include "crypto/CryptoHash.h"
 
 const Uuid KeePass2::CIPHER_AES = Uuid(QByteArray::fromHex("31c1f2e6bf714350be5805216afc5aff"));
 const Uuid KeePass2::CIPHER_TWOFISH = Uuid(QByteArray::fromHex("ad68f29f576f4bb9a36ad47af965346c"));
@@ -29,6 +30,19 @@ const Uuid KeePass2::KDF_ARGON2 = Uuid(QByteArray::fromHex("EF636DDF8C29444B91F7
 
 const QByteArray KeePass2::INNER_STREAM_SALSA20_IV("\xE8\x30\x09\x4B\x97\x20\x5D\x2A");
 
+const QString KeePass2::KDFPARAM_UUID("$UUID");
+// AES parameters
+const QString KeePass2::KDFPARAM_AES_ROUNDS("R");
+const QString KeePass2::KDFPARAM_AES_SEED("S");
+// Argon2 parameters
+const QString KeePass2::KDFPARAM_ARGON2_SALT("S");
+const QString KeePass2::KDFPARAM_ARGON2_PARALLELISM("P");
+const QString KeePass2::KDFPARAM_ARGON2_MEMORY("M");
+const QString KeePass2::KDFPARAM_ARGON2_ITERATIONS("I");
+const QString KeePass2::KDFPARAM_ARGON2_VERSION("V");
+const QString KeePass2::KDFPARAM_ARGON2_SECRET("K");
+const QString KeePass2::KDFPARAM_ARGON2_ASSOCDATA("A");
+
 const QList<QPair<Uuid, QString>> KeePass2::CIPHERS {
         qMakePair(KeePass2::CIPHER_AES, QObject::tr("AES: 256-bit")),
         qMakePair(KeePass2::CIPHER_TWOFISH, QObject::tr("Twofish: 256-bit")),
@@ -39,6 +53,38 @@ const QList<QPair<Uuid, QString>> KeePass2::KDFS {
         qMakePair(KeePass2::KDF_ARGON2, QObject::tr("Argon2")),
 };
 
+QByteArray KeePass2::hmacKey(QByteArray masterSeed, QByteArray transformedMasterKey) {
+    CryptoHash hmacKeyHash(CryptoHash::Sha512);
+    hmacKeyHash.addData(masterSeed);
+    hmacKeyHash.addData(transformedMasterKey);
+    hmacKeyHash.addData(QByteArray(1, '\x01'));
+    return hmacKeyHash.result();
+}
+
+QSharedPointer<Kdf> KeePass2::kdfFromParameters(const QVariantMap &p)
+{
+    QByteArray uuidBytes = p.value(KDFPARAM_UUID).toByteArray();
+    if (uuidBytes.size() != Uuid::Length) {
+        return nullptr;
+    }
+
+    QSharedPointer<Kdf> kdf(uuidToKdf(Uuid(uuidBytes)));
+    if (kdf.isNull()) {
+        return nullptr;
+    }
+
+    if (!kdf->processParameters(p)) {
+        return nullptr;
+    }
+
+    return kdf;
+}
+
+QVariantMap KeePass2::kdfToParameters(QSharedPointer<Kdf> kdf)
+{
+    return kdf->writeParameters();
+}
+
 QSharedPointer<Kdf> KeePass2::uuidToKdf(const Uuid& uuid)
 {
     if (uuid == KDF_AES) {