From 40c85028228d07c878cb58fc31222fb4d163a89f Mon Sep 17 00:00:00 2001 From: Daniel P. Berrange Date: Fri, 22 Jul 2016 13:53:34 +0100 Subject: crypto: add support for querying parameters for block encryption When creating new block encryption volumes, we accept a list of parameters to control the formatting process. It is useful to be able to query what those parameters were for existing block devices. Add a qcrypto_block_get_info() method which returns a QCryptoBlockInfo instance to report this data. Signed-off-by: Daniel P. Berrange Message-id: 1469192015-16487-2-git-send-email-berrange@redhat.com Reviewed-by: Eric Blake Signed-off-by: Max Reitz --- qapi/crypto.json | 87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) (limited to 'qapi') diff --git a/qapi/crypto.json b/qapi/crypto.json index 4c4a3e07f4..34d2583154 100644 --- a/qapi/crypto.json +++ b/qapi/crypto.json @@ -224,3 +224,90 @@ 'discriminator': 'format', 'data': { 'qcow': 'QCryptoBlockOptionsQCow', 'luks': 'QCryptoBlockCreateOptionsLUKS' } } + + +## +# QCryptoBlockInfoBase: +# +# The common information that applies to all full disk +# encryption formats +# +# @format: the encryption format +# +# Since: 2.7 +## +{ 'struct': 'QCryptoBlockInfoBase', + 'data': { 'format': 'QCryptoBlockFormat' }} + + +## +# QCryptoBlockInfoLUKSSlot: +# +# Information about the LUKS block encryption key +# slot options +# +# @active: whether the key slot is currently in use +# @key-offset: offset to the key material in bytes +# @iters: #optional number of PBKDF2 iterations for key material +# @stripes: #optional number of stripes for splitting key material +# +# Since: 2.7 +## +{ 'struct': 'QCryptoBlockInfoLUKSSlot', + 'data': {'active': 'bool', + '*iters': 'int', + '*stripes': 'int', + 'key-offset': 'int' } } + + +## +# QCryptoBlockInfoLUKS: +# +# Information about the LUKS block encryption options +# +# @cipher-alg: the cipher algorithm for data encryption +# @cipher-mode: the cipher mode for data encryption +# @ivgen-alg: the initialization vector generator +# @ivgen-hash-alg: #optional the initialization vector generator hash +# @hash-alg: the master key hash algorithm +# @payload-offset: offset to the payload data in bytes +# @master-key-iters: number of PBKDF2 iterations for key material +# @uuid: unique identifier for the volume +# @slots: information about each key slot +# +# Since: 2.7 +## +{ 'struct': 'QCryptoBlockInfoLUKS', + 'data': {'cipher-alg': 'QCryptoCipherAlgorithm', + 'cipher-mode': 'QCryptoCipherMode', + 'ivgen-alg': 'QCryptoIVGenAlgorithm', + '*ivgen-hash-alg': 'QCryptoHashAlgorithm', + 'hash-alg': 'QCryptoHashAlgorithm', + 'payload-offset': 'int', + 'master-key-iters': 'int', + 'uuid': 'str', + 'slots': [ 'QCryptoBlockInfoLUKSSlot' ] }} + +## +# QCryptoBlockInfoQCow: +# +# Information about the QCow block encryption options +# +# Since: 2.7 +## +{ 'struct': 'QCryptoBlockInfoQCow', + 'data': { }} + + +## +# QCryptoBlockInfo: +# +# Information about the block encryption options +# +# Since: 2.7 +## +{ 'union': 'QCryptoBlockInfo', + 'base': 'QCryptoBlockInfoBase', + 'discriminator': 'format', + 'data': { 'qcow': 'QCryptoBlockInfoQCow', + 'luks': 'QCryptoBlockInfoLUKS' } } -- cgit v1.2.3-55-g7522 From c7c4cf498fc46c0dc6b0866ea5f00e056cae15bb Mon Sep 17 00:00:00 2001 From: Daniel P. Berrange Date: Fri, 22 Jul 2016 13:53:35 +0100 Subject: block: export LUKS specific data to qemu-img info The qemu-img info command has the ability to expose format specific metadata about volumes. Wire up this facility for the LUKS driver to report on cipher configuration and key slot usage. $ qemu-img info ~/VirtualMachines/demo.luks image: /home/berrange/VirtualMachines/demo.luks file format: luks virtual size: 98M (102760448 bytes) disk size: 100M encrypted: yes Format specific information: ivgen alg: plain64 hash alg: sha1 cipher alg: aes-128 uuid: 6ddee74b-3a22-408c-8909-6789d4fa2594 cipher mode: xts slots: [0]: active: true iters: 572706 key offset: 4096 stripes: 4000 [1]: active: false key offset: 135168 [2]: active: false key offset: 266240 [3]: active: false key offset: 397312 [4]: active: false key offset: 528384 [5]: active: false key offset: 659456 [6]: active: false key offset: 790528 [7]: active: false key offset: 921600 payload offset: 2097152 master key iters: 142375 One somewhat undesirable artifact is that the data fields are printed out in (apparently) random order. This will be addressed later by changing the way the block layer pretty-prints the image specific data. Signed-off-by: Daniel P. Berrange Message-id: 1469192015-16487-3-git-send-email-berrange@redhat.com Reviewed-by: Eric Blake Signed-off-by: Max Reitz --- block/crypto.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ qapi/block-core.json | 6 +++++- 2 files changed, 54 insertions(+), 1 deletion(-) (limited to 'qapi') diff --git a/block/crypto.c b/block/crypto.c index 7eaa0571b5..7f61e12686 100644 --- a/block/crypto.c +++ b/block/crypto.c @@ -563,6 +563,53 @@ static int block_crypto_create_luks(const char *filename, filename, opts, errp); } +static int block_crypto_get_info_luks(BlockDriverState *bs, + BlockDriverInfo *bdi) +{ + BlockDriverInfo subbdi; + int ret; + + ret = bdrv_get_info(bs->file->bs, &subbdi); + if (ret != 0) { + return ret; + } + + bdi->unallocated_blocks_are_zero = false; + bdi->can_write_zeroes_with_unmap = false; + bdi->cluster_size = subbdi.cluster_size; + + return 0; +} + +static ImageInfoSpecific * +block_crypto_get_specific_info_luks(BlockDriverState *bs) +{ + BlockCrypto *crypto = bs->opaque; + ImageInfoSpecific *spec_info; + QCryptoBlockInfo *info; + + info = qcrypto_block_get_info(crypto->block, NULL); + if (!info) { + return NULL; + } + if (info->format != Q_CRYPTO_BLOCK_FORMAT_LUKS) { + qapi_free_QCryptoBlockInfo(info); + return NULL; + } + + spec_info = g_new(ImageInfoSpecific, 1); + spec_info->type = IMAGE_INFO_SPECIFIC_KIND_LUKS; + spec_info->u.luks.data = g_new(QCryptoBlockInfoLUKS, 1); + *spec_info->u.luks.data = info->u.luks; + + /* Blank out pointers we've just stolen to avoid double free */ + memset(&info->u.luks, 0, sizeof(info->u.luks)); + + qapi_free_QCryptoBlockInfo(info); + + return spec_info; +} + BlockDriver bdrv_crypto_luks = { .format_name = "luks", .instance_size = sizeof(BlockCrypto), @@ -576,6 +623,8 @@ BlockDriver bdrv_crypto_luks = { .bdrv_co_readv = block_crypto_co_readv, .bdrv_co_writev = block_crypto_co_writev, .bdrv_getlength = block_crypto_getlength, + .bdrv_get_info = block_crypto_get_info_luks, + .bdrv_get_specific_info = block_crypto_get_specific_info_luks, }; static void block_crypto_init(void) diff --git a/qapi/block-core.json b/qapi/block-core.json index f462345ca3..d4bab5d991 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -85,7 +85,11 @@ { 'union': 'ImageInfoSpecific', 'data': { 'qcow2': 'ImageInfoSpecificQCow2', - 'vmdk': 'ImageInfoSpecificVmdk' + 'vmdk': 'ImageInfoSpecificVmdk', + # If we need to add block driver specific parameters for + # LUKS in future, then we'll subclass QCryptoBlockInfoLUKS + # to define a ImageInfoSpecificLUKS + 'luks': 'QCryptoBlockInfoLUKS' } } ## -- cgit v1.2.3-55-g7522