The LUKS disk with detached header consists of a separate LUKS
header and payload. This LUKS disk type should be formatted
as follows:
1. add the secret to lock/unlock the cipher stored in the
detached LUKS header
$ virsh qemu-monitor-command vm '{"execute":"object-add",
> "arguments":{"qom-type": "secret", "id": "sec0", "data": "foo"}}'
2. create a header img with 0 size
$ virsh qemu-monitor-command vm '{"execute":"blockdev-create",
> "arguments":{"job-id":"job0", "options":{"driver":"file",
> "filename":"/path/to/detached_luks_header.img", "size":0 }}}'
3. add protocol blockdev node for header
$ virsh qemu-monitor-command vm '{"execute":"blockdev-add",
> "arguments": {"driver":"file", "filename":
> "/path/to/detached_luks_header.img", "node-name":
> "detached-luks-header-storage"}}'
4. create a payload img with 0 size
$ virsh qemu-monitor-command vm '{"execute":"blockdev-create",
> "arguments":{"job-id":"job1", "options":{"driver":"file",
> "filename":"/path/to/detached_luks_payload_raw.img", "size":0}}}'
5. add protocol blockdev node for payload
$ virsh qemu-monitor-command vm '{"execute":"blockdev-add",
> "arguments": {"driver":"file", "filename":
> "/path/to/detached_luks_payload_raw.img", "node-name":
> "luks-payload-raw-storage"}}'
6. do the formatting with 128M size
$ virsh qemu-monitor-command c81_node1 '{"execute":"blockdev-create",
> "arguments":{"job-id":"job2", "options":{"driver":"luks", "header":
> "detached-luks-header-storage", "file":"luks-payload-raw-storage",
> "size":134217728, "preallocation":"full", "key-secret":"sec0" }}}'
Signed-off-by: Hyman Huang <yong.huang@smartx.com>
---
block/crypto.c | 109 ++++++++++++++++++++++++++++++++++++++++----
crypto/block-luks.c | 6 ++-
crypto/block.c | 1 +
3 files changed, 106 insertions(+), 10 deletions(-)
diff --git a/block/crypto.c b/block/crypto.c
index 78fbe79c95..76cc8bda49 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -160,6 +160,48 @@ error:
return ret;
}
+static int coroutine_fn GRAPH_UNLOCKED
+block_crypto_co_format_luks_payload(BlockdevCreateOptionsLUKS *luks_opts,
+ Error **errp)
+{
+ BlockDriverState *bs = NULL;
+ BlockBackend *blk = NULL;
+ Error *local_error = NULL;
+ int ret;
+
+ if (luks_opts->size > INT64_MAX) {
+ return -EFBIG;
+ }
+
+ bs = bdrv_co_open_blockdev_ref(luks_opts->file, errp);
+ if (bs == NULL) {
+ return -EIO;
+ }
+
+ blk = blk_co_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE,
+ BLK_PERM_ALL, errp);
+ if (!blk) {
+ ret = -EPERM;
+ goto fail;
+ }
+
+ ret = blk_truncate(blk, luks_opts->size, true,
+ luks_opts->preallocation, 0, &local_error);
+ if (ret < 0) {
+ if (ret == -EFBIG) {
+ /* Replace the error message with a better one */
+ error_free(local_error);
+ error_setg(errp, "The requested file size is too large");
+ }
+ goto fail;
+ }
+
+ ret = 0;
+
+fail:
+ bdrv_co_unref(bs);
+ return ret;
+}
static QemuOptsList block_crypto_runtime_opts_luks = {
.name = "crypto",
@@ -651,6 +693,7 @@ static int coroutine_fn GRAPH_UNLOCKED
block_crypto_co_create_luks(BlockdevCreateOptions *create_options, Error **errp)
{
BlockdevCreateOptionsLUKS *luks_opts;
+ BlockDriverState *hdr_bs = NULL;
BlockDriverState *bs = NULL;
QCryptoBlockCreateOptions create_opts;
PreallocMode preallocation = PREALLOC_MODE_OFF;
@@ -659,8 +702,22 @@ block_crypto_co_create_luks(BlockdevCreateOptions *create_options, Error **errp)
assert(create_options->driver == BLOCKDEV_DRIVER_LUKS);
luks_opts = &create_options->u.luks;
- if (luks_opts->file == NULL) {
- error_setg(errp, "Formatting LUKS disk requires parameter 'file'");
+ if (luks_opts->header == NULL && luks_opts->file == NULL) {
+ error_setg(errp, "Either the parameter 'header' or 'file' should "
+ "be specified");
+ return -EINVAL;
+ }
+
+ if (luks_opts->detached_header && luks_opts->header == NULL) {
+ error_setg(errp, "Formatting a detached LUKS disk requries "
+ "'header' to be specified");
+ return -EINVAL;
+ }
+
+ if ((luks_opts->preallocation != PREALLOC_MODE_OFF) &&
+ (luks_opts->file == NULL)) {
+ error_setg(errp, "Parameter 'preallocation' requries 'file' to be "
+ "specified for formatting LUKS disk");
return -EINVAL;
}
@@ -673,7 +730,40 @@ block_crypto_co_create_luks(BlockdevCreateOptions *create_options, Error **errp)
preallocation = luks_opts->preallocation;
}
- if (luks_opts->file) {
+ if (luks_opts->header) {
+ hdr_bs = bdrv_co_open_blockdev_ref(luks_opts->header, errp);
+ if (hdr_bs == NULL) {
+ return -EIO;
+ }
+
+ /*
+ * If blockdev reference of header is specified,
+ * detached_header default to true
+ */
+ create_opts.u.luks.detached_header = true;
+
+ /* Format the LUKS header node */
+ ret = block_crypto_co_create_generic(hdr_bs, 0, &create_opts,
+ PREALLOC_MODE_OFF, errp);
+ if (ret < 0) {
+ goto hdr_bs_failed;
+ }
+
+ /* Format the LUKS payload node */
+ if (luks_opts->file) {
+ ret = block_crypto_co_format_luks_payload(luks_opts, errp);
+ if (ret < 0) {
+ goto hdr_bs_failed;
+ }
+ }
+
+ ret = 0;
+
+hdr_bs_failed:
+ bdrv_co_unref(hdr_bs);
+ return ret;
+ } else if (luks_opts->file) {
+ /* None detached LUKS header path */
bs = bdrv_co_open_blockdev_ref(luks_opts->file, errp);
if (bs == NULL) {
return -EIO;
@@ -682,14 +772,15 @@ block_crypto_co_create_luks(BlockdevCreateOptions *create_options, Error **errp)
ret = block_crypto_co_create_generic(bs, luks_opts->size, &create_opts,
preallocation, errp);
if (ret < 0) {
- goto fail;
+ goto bs_failed;
}
- }
- ret = 0;
-fail:
- bdrv_co_unref(bs);
- return ret;
+ ret = 0;
+
+bs_failed:
+ bdrv_co_unref(bs);
+ return ret;
+ }
}
static int coroutine_fn GRAPH_UNLOCKED
diff --git a/crypto/block-luks.c b/crypto/block-luks.c
index 48443ffcae..474c7aee2e 100644
--- a/crypto/block-luks.c
+++ b/crypto/block-luks.c
@@ -1561,8 +1561,12 @@ qcrypto_block_luks_create(QCryptoBlock *block,
block->payload_offset =
qcrypto_block_luks_payload_offset(luks->header.payload_offset_sector);
+ block->detached_header_size =
+ (header_sectors + QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS *
+ split_key_sectors) * block->sector_size;
+
/* Reserve header space to match payload offset */
- initfunc(block, block->payload_offset, opaque, &local_err);
+ initfunc(block, block->detached_header_size, opaque, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto error;
diff --git a/crypto/block.c b/crypto/block.c
index 7bb4b74a37..ea493f056e 100644
--- a/crypto/block.c
+++ b/crypto/block.c
@@ -102,6 +102,7 @@ QCryptoBlock *qcrypto_block_create(QCryptoBlockCreateOptions *options,
}
block->driver = qcrypto_block_drivers[options->format];
+ block->detached_header = options->u.luks.detached_header;
if (block->driver->create(block, options, optprefix, initfunc,
writefunc, opaque, errp) < 0) {
--
2.39.1