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, 185 insertions, 0 deletions

diff --git a/crypto/block-qcow.c b/crypto/block-qcow.c
new file mode 100644
index 000000000..4d7cf36a8
--- /dev/null
+++ b/crypto/block-qcow.c
@@ -0,0 +1,185 @@
+/*
+ * QEMU Crypto block device encryption QCow/QCow2 AES-CBC format
+ *
+ * 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 2.1 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/>.
+ *
+ */
+
+/*
+ * Note that the block encryption implemented in this file is broken
+ * by design. This exists only to allow data to be liberated from
+ * existing qcow[2] images and should not be used in any new areas.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+
+#include "block-qcow.h"
+#include "crypto/secret.h"
+
+#define QCRYPTO_BLOCK_QCOW_SECTOR_SIZE 512
+
+
+static bool
+qcrypto_block_qcow_has_format(const uint8_t *buf G_GNUC_UNUSED,
+                              size_t buf_size G_GNUC_UNUSED)
+{
+    return false;
+}
+
+
+static int
+qcrypto_block_qcow_init(QCryptoBlock *block,
+                        const char *keysecret,
+                        size_t n_threads,
+                        Error **errp)
+{
+    char *password;
+    int ret;
+    uint8_t keybuf[16];
+    int len;
+
+    memset(keybuf, 0, 16);
+
+    password = qcrypto_secret_lookup_as_utf8(keysecret, errp);
+    if (!password) {
+        return -1;
+    }
+
+    len = strlen(password);
+    memcpy(keybuf, password, MIN(len, sizeof(keybuf)));
+    g_free(password);
+
+    block->niv = qcrypto_cipher_get_iv_len(QCRYPTO_CIPHER_ALG_AES_128,
+                                           QCRYPTO_CIPHER_MODE_CBC);
+    block->ivgen = qcrypto_ivgen_new(QCRYPTO_IVGEN_ALG_PLAIN64,
+                                     0, 0, NULL, 0, errp);
+    if (!block->ivgen) {
+        ret = -ENOTSUP;
+        goto fail;
+    }
+
+    ret = qcrypto_block_init_cipher(block, QCRYPTO_CIPHER_ALG_AES_128,
+                                    QCRYPTO_CIPHER_MODE_CBC,
+                                    keybuf, G_N_ELEMENTS(keybuf),
+                                    n_threads, errp);
+    if (ret < 0) {
+        ret = -ENOTSUP;
+        goto fail;
+    }
+
+    block->sector_size = QCRYPTO_BLOCK_QCOW_SECTOR_SIZE;
+    block->payload_offset = 0;
+
+    return 0;
+
+ fail:
+    qcrypto_block_free_cipher(block);
+    qcrypto_ivgen_free(block->ivgen);
+    return ret;
+}
+
+
+static int
+qcrypto_block_qcow_open(QCryptoBlock *block,
+                        QCryptoBlockOpenOptions *options,
+                        const char *optprefix,
+                        QCryptoBlockReadFunc readfunc G_GNUC_UNUSED,
+                        void *opaque G_GNUC_UNUSED,
+                        unsigned int flags,
+                        size_t n_threads,
+                        Error **errp)
+{
+    if (flags & QCRYPTO_BLOCK_OPEN_NO_IO) {
+        block->sector_size = QCRYPTO_BLOCK_QCOW_SECTOR_SIZE;
+        block->payload_offset = 0;
+        return 0;
+    } else {
+        if (!options->u.qcow.key_secret) {
+            error_setg(errp,
+                       "Parameter '%skey-secret' is required for cipher",
+                       optprefix ? optprefix : "");
+            return -1;
+        }
+        return qcrypto_block_qcow_init(block, options->u.qcow.key_secret,
+                                       n_threads, errp);
+    }
+}
+
+
+static int
+qcrypto_block_qcow_create(QCryptoBlock *block,
+                          QCryptoBlockCreateOptions *options,
+                          const char *optprefix,
+                          QCryptoBlockInitFunc initfunc G_GNUC_UNUSED,
+                          QCryptoBlockWriteFunc writefunc G_GNUC_UNUSED,
+                          void *opaque G_GNUC_UNUSED,
+                          Error **errp)
+{
+    if (!options->u.qcow.key_secret) {
+        error_setg(errp, "Parameter '%skey-secret' is required for cipher",
+                   optprefix ? optprefix : "");
+        return -1;
+    }
+    /* QCow2 has no special header, since everything is hardwired */
+    return qcrypto_block_qcow_init(block, options->u.qcow.key_secret, 1, errp);
+}
+
+
+static void
+qcrypto_block_qcow_cleanup(QCryptoBlock *block)
+{
+}
+
+
+static int
+qcrypto_block_qcow_decrypt(QCryptoBlock *block,
+                           uint64_t offset,
+                           uint8_t *buf,
+                           size_t len,
+                           Error **errp)
+{
+    assert(QEMU_IS_ALIGNED(offset, QCRYPTO_BLOCK_QCOW_SECTOR_SIZE));
+    assert(QEMU_IS_ALIGNED(len, QCRYPTO_BLOCK_QCOW_SECTOR_SIZE));
+    return qcrypto_block_decrypt_helper(block,
+                                        QCRYPTO_BLOCK_QCOW_SECTOR_SIZE,
+                                        offset, buf, len, errp);
+}
+
+
+static int
+qcrypto_block_qcow_encrypt(QCryptoBlock *block,
+                           uint64_t offset,
+                           uint8_t *buf,
+                           size_t len,
+                           Error **errp)
+{
+    assert(QEMU_IS_ALIGNED(offset, QCRYPTO_BLOCK_QCOW_SECTOR_SIZE));
+    assert(QEMU_IS_ALIGNED(len, QCRYPTO_BLOCK_QCOW_SECTOR_SIZE));
+    return qcrypto_block_encrypt_helper(block,
+                                        QCRYPTO_BLOCK_QCOW_SECTOR_SIZE,
+                                        offset, buf, len, errp);
+}
+
+
+const QCryptoBlockDriver qcrypto_block_driver_qcow = {
+    .open = qcrypto_block_qcow_open,
+    .create = qcrypto_block_qcow_create,
+    .cleanup = qcrypto_block_qcow_cleanup,
+    .decrypt = qcrypto_block_qcow_decrypt,
+    .encrypt = qcrypto_block_qcow_encrypt,
+    .has_format = qcrypto_block_qcow_has_format,
+};