crypto: add support for generating initialization vectors

There are a number of different algorithms that can be used
to generate initialization vectors for disk encryption. This
introduces a simple internal QCryptoBlockIV object to provide
a consistent internal API to the different algorithms. The
initially implemented algorithms are 'plain', 'plain64' and
'essiv', each matching the same named algorithm provided
by the Linux kernel dm-crypt driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/crypto/ivgenpriv.h b/crypto/ivgenpriv.h
new file mode 100644
index 0000000..7b87e02
--- /dev/null
+++ b/crypto/ivgenpriv.h
@@ -0,0 +1,49 @@
+/*
+ * QEMU Crypto block IV generator
+ *
+ * Copyright (c) 2015-2016 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef QCRYPTO_IVGEN_PRIV_H__
+#define QCRYPTO_IVGEN_PRIV_H__
+
+#include "crypto/ivgen.h"
+
+typedef struct QCryptoIVGenDriver QCryptoIVGenDriver;
+
+struct QCryptoIVGenDriver {
+    int (*init)(QCryptoIVGen *ivgen,
+                const uint8_t *key, size_t nkey,
+                Error **errp);
+    int (*calculate)(QCryptoIVGen *ivgen,
+                     uint64_t sector,
+                     uint8_t *iv, size_t niv,
+                     Error **errp);
+    void (*cleanup)(QCryptoIVGen *ivgen);
+};
+
+struct QCryptoIVGen {
+    QCryptoIVGenDriver *driver;
+    void *private;
+
+    QCryptoIVGenAlgorithm algorithm;
+    QCryptoCipherAlgorithm cipher;
+    QCryptoHashAlgorithm hash;
+};
+
+
+#endif /* QCRYPTO_IVGEN_PRIV_H__ */