Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 150 insertions, 0 deletions

diff --git a/crypto/hmac-gcrypt.c b/crypto/hmac-gcrypt.c
new file mode 100644
index 000000000..0c6f97971
--- /dev/null
+++ b/crypto/hmac-gcrypt.c
@@ -0,0 +1,150 @@
+/*
+ * QEMU Crypto hmac algorithms (based on libgcrypt)
+ *
+ * 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"
+#include "hmacpriv.h"
+#include <gcrypt.h>
+
+static int qcrypto_hmac_alg_map[QCRYPTO_HASH_ALG__MAX] = {
+    [QCRYPTO_HASH_ALG_MD5] = GCRY_MAC_HMAC_MD5,
+    [QCRYPTO_HASH_ALG_SHA1] = GCRY_MAC_HMAC_SHA1,
+    [QCRYPTO_HASH_ALG_SHA224] = GCRY_MAC_HMAC_SHA224,
+    [QCRYPTO_HASH_ALG_SHA256] = GCRY_MAC_HMAC_SHA256,
+    [QCRYPTO_HASH_ALG_SHA384] = GCRY_MAC_HMAC_SHA384,
+    [QCRYPTO_HASH_ALG_SHA512] = GCRY_MAC_HMAC_SHA512,
+    [QCRYPTO_HASH_ALG_RIPEMD160] = GCRY_MAC_HMAC_RMD160,
+};
+
+typedef struct QCryptoHmacGcrypt QCryptoHmacGcrypt;
+struct QCryptoHmacGcrypt {
+    gcry_mac_hd_t handle;
+};
+
+bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
+{
+    if (alg < G_N_ELEMENTS(qcrypto_hmac_alg_map) &&
+        qcrypto_hmac_alg_map[alg] != GCRY_MAC_NONE) {
+        return true;
+    }
+
+    return false;
+}
+
+void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
+                           const uint8_t *key, size_t nkey,
+                           Error **errp)
+{
+    QCryptoHmacGcrypt *ctx;
+    gcry_error_t err;
+
+    if (!qcrypto_hmac_supports(alg)) {
+        error_setg(errp, "Unsupported hmac algorithm %s",
+                   QCryptoHashAlgorithm_str(alg));
+        return NULL;
+    }
+
+    ctx = g_new0(QCryptoHmacGcrypt, 1);
+
+    err = gcry_mac_open(&ctx->handle, qcrypto_hmac_alg_map[alg],
+                        GCRY_MAC_FLAG_SECURE, NULL);
+    if (err != 0) {
+        error_setg(errp, "Cannot initialize hmac: %s",
+                   gcry_strerror(err));
+        goto error;
+    }
+
+    err = gcry_mac_setkey(ctx->handle, (const void *)key, nkey);
+    if (err != 0) {
+        error_setg(errp, "Cannot set key: %s",
+                   gcry_strerror(err));
+        gcry_mac_close(ctx->handle);
+        goto error;
+    }
+
+    return ctx;
+
+error:
+    g_free(ctx);
+    return NULL;
+}
+
+static void
+qcrypto_gcrypt_hmac_ctx_free(QCryptoHmac *hmac)
+{
+    QCryptoHmacGcrypt *ctx;
+
+    ctx = hmac->opaque;
+    gcry_mac_close(ctx->handle);
+
+    g_free(ctx);
+}
+
+static int
+qcrypto_gcrypt_hmac_bytesv(QCryptoHmac *hmac,
+                           const struct iovec *iov,
+                           size_t niov,
+                           uint8_t **result,
+                           size_t *resultlen,
+                           Error **errp)
+{
+    QCryptoHmacGcrypt *ctx;
+    gcry_error_t err;
+    uint32_t ret;
+    int i;
+
+    ctx = hmac->opaque;
+
+    for (i = 0; i < niov; i++) {
+        gcry_mac_write(ctx->handle, iov[i].iov_base, iov[i].iov_len);
+    }
+
+    ret = gcry_mac_get_algo_maclen(qcrypto_hmac_alg_map[hmac->alg]);
+    if (ret <= 0) {
+        error_setg(errp, "Unable to get hmac length: %s",
+                   gcry_strerror(ret));
+        return -1;
+    }
+
+    if (*resultlen == 0) {
+        *resultlen = ret;
+        *result = g_new0(uint8_t, *resultlen);
+    } else if (*resultlen != ret) {
+        error_setg(errp, "Result buffer size %zu is smaller than hmac %d",
+                   *resultlen, ret);
+        return -1;
+    }
+
+    err = gcry_mac_read(ctx->handle, *result, resultlen);
+    if (err != 0) {
+        error_setg(errp, "Cannot get result: %s",
+                   gcry_strerror(err));
+        return -1;
+    }
+
+    err = gcry_mac_reset(ctx->handle);
+    if (err != 0) {
+        error_setg(errp, "Cannot reset hmac context: %s",
+                   gcry_strerror(err));
+        return -1;
+    }
+
+    return 0;
+}
+
+QCryptoHmacDriver qcrypto_hmac_lib_driver = {
+    .hmac_bytesv = qcrypto_gcrypt_hmac_bytesv,
+    .hmac_free = qcrypto_gcrypt_hmac_ctx_free,
+};