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.hu...@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