crypto: add HMAC algorithms framework

This patch introduce HMAC algorithms framework.

Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

crypto/hmac-glib.c

@@ -0,0 +1,44 @@
+/*
+ * QEMU Crypto hmac algorithms (based on glib)
+ *
+ * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
+ *
+ * Authors:
+ *    Longpeng(Mike) <longpeng2@huawei.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version.  See the COPYING file in the
+ * top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "crypto/hmac.h"
+
+bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
+{
+    return false;
+}
+
+QCryptoHmac *qcrypto_hmac_new(QCryptoHashAlgorithm alg,
+                              const uint8_t *key, size_t nkey,
+                              Error **errp)
+{
+    return NULL;
+}
+
+void qcrypto_hmac_free(QCryptoHmac *hmac)
+{
+    return;
+}
+
+int qcrypto_hmac_bytesv(QCryptoHmac *hmac,
+                        const struct iovec *iov,
+                        size_t niov,
+                        uint8_t **result,
+                        size_t *resultlen,
+                        Error **errp)
+{
+    return -1;
+}