From: Daniel P. Berrange Date: Wed, 27 Sep 2017 12:53:36 +0000 (+0100) Subject: crypto: expose encryption sector size in APIs X-Git-Tag: v2.11.0-rc0~61^2^2~9 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=850f49de9b57511dcaf2cd7e45059f8f38fadf3b;p=thirdparty%2Fqemu.git crypto: expose encryption sector size in APIs While current encryption schemes all have a fixed sector size of 512 bytes, this is not guaranteed to be the case in future. Expose the sector size in the APIs so the block layer can remove assumptions about fixed 512 byte sectors. Reviewed-by: Max Reitz Reviewed-by: Eric Blake Signed-off-by: Daniel P. Berrange Message-id: 20170927125340.12360-3-berrange@redhat.com Signed-off-by: Max Reitz --- diff --git a/crypto/block-luks.c b/crypto/block-luks.c index 36bc856084d..a9062bb0f21 100644 --- a/crypto/block-luks.c +++ b/crypto/block-luks.c @@ -846,8 +846,9 @@ qcrypto_block_luks_open(QCryptoBlock *block, } } + block->sector_size = QCRYPTO_BLOCK_LUKS_SECTOR_SIZE; block->payload_offset = luks->header.payload_offset * - QCRYPTO_BLOCK_LUKS_SECTOR_SIZE; + block->sector_size; luks->cipher_alg = cipheralg; luks->cipher_mode = ciphermode; @@ -1240,8 +1241,9 @@ qcrypto_block_luks_create(QCryptoBlock *block, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) * QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS); + block->sector_size = QCRYPTO_BLOCK_LUKS_SECTOR_SIZE; block->payload_offset = luks->header.payload_offset * - QCRYPTO_BLOCK_LUKS_SECTOR_SIZE; + block->sector_size; /* Reserve header space to match payload offset */ initfunc(block, block->payload_offset, opaque, &local_err); diff --git a/crypto/block-qcow.c b/crypto/block-qcow.c index a456fe338ba..4dd594a9ba2 100644 --- a/crypto/block-qcow.c +++ b/crypto/block-qcow.c @@ -80,6 +80,7 @@ qcrypto_block_qcow_init(QCryptoBlock *block, goto fail; } + block->sector_size = QCRYPTO_BLOCK_QCOW_SECTOR_SIZE; block->payload_offset = 0; return 0; diff --git a/crypto/block.c b/crypto/block.c index c382393d9a6..a7a9ad240e3 100644 --- a/crypto/block.c +++ b/crypto/block.c @@ -170,6 +170,12 @@ uint64_t qcrypto_block_get_payload_offset(QCryptoBlock *block) } +uint64_t qcrypto_block_get_sector_size(QCryptoBlock *block) +{ + return block->sector_size; +} + + void qcrypto_block_free(QCryptoBlock *block) { if (!block) { diff --git a/crypto/blockpriv.h b/crypto/blockpriv.h index 0edb810e22d..d227522d88c 100644 --- a/crypto/blockpriv.h +++ b/crypto/blockpriv.h @@ -36,6 +36,7 @@ struct QCryptoBlock { QCryptoHashAlgorithm kdfhash; size_t niv; uint64_t payload_offset; /* In bytes */ + uint64_t sector_size; /* In bytes */ }; struct QCryptoBlockDriver { diff --git a/include/crypto/block.h b/include/crypto/block.h index f0e543bee1f..13232b2472c 100644 --- a/include/crypto/block.h +++ b/include/crypto/block.h @@ -240,6 +240,21 @@ QCryptoHashAlgorithm qcrypto_block_get_kdf_hash(QCryptoBlock *block); */ uint64_t qcrypto_block_get_payload_offset(QCryptoBlock *block); +/** + * qcrypto_block_get_sector_size: + * @block: the block encryption object + * + * Get the size of sectors used for payload encryption. A new + * IV is used at the start of each sector. The encryption + * sector size is not required to match the sector size of the + * underlying storage. For example LUKS will always use a 512 + * byte sector size, even if the volume is on a disk with 4k + * sectors. + * + * Returns: the sector in bytes + */ +uint64_t qcrypto_block_get_sector_size(QCryptoBlock *block); + /** * qcrypto_block_free: * @block: the block encryption object