diff options
Diffstat (limited to 'block/crypto.c')
| -rw-r--r-- | block/crypto.c | 207 |
1 files changed, 190 insertions, 17 deletions
diff --git a/block/crypto.c b/block/crypto.c index 973b57b3eb..2636e959ae 100644 --- a/block/crypto.c +++ b/block/crypto.c @@ -37,6 +37,7 @@ typedef struct BlockCrypto BlockCrypto; struct BlockCrypto { QCryptoBlock *block; + bool updating_keys; }; @@ -71,6 +72,24 @@ static ssize_t block_crypto_read_func(QCryptoBlock *block, return ret; } +static ssize_t block_crypto_write_func(QCryptoBlock *block, + size_t offset, + const uint8_t *buf, + size_t buflen, + void *opaque, + Error **errp) +{ + BlockDriverState *bs = opaque; + ssize_t ret; + + ret = bdrv_pwrite(bs->file, offset, buf, buflen); + if (ret < 0) { + error_setg_errno(errp, -ret, "Could not write encryption header"); + return ret; + } + return ret; +} + struct BlockCryptoCreateData { BlockBackend *blk; @@ -79,12 +98,12 @@ struct BlockCryptoCreateData { }; -static ssize_t block_crypto_write_func(QCryptoBlock *block, - size_t offset, - const uint8_t *buf, - size_t buflen, - void *opaque, - Error **errp) +static ssize_t block_crypto_create_write_func(QCryptoBlock *block, + size_t offset, + const uint8_t *buf, + size_t buflen, + void *opaque, + Error **errp) { struct BlockCryptoCreateData *data = opaque; ssize_t ret; @@ -97,11 +116,10 @@ static ssize_t block_crypto_write_func(QCryptoBlock *block, return ret; } - -static ssize_t block_crypto_init_func(QCryptoBlock *block, - size_t headerlen, - void *opaque, - Error **errp) +static ssize_t block_crypto_create_init_func(QCryptoBlock *block, + size_t headerlen, + void *opaque, + Error **errp) { struct BlockCryptoCreateData *data = opaque; Error *local_error = NULL; @@ -167,6 +185,19 @@ static QemuOptsList block_crypto_create_opts_luks = { }; +static QemuOptsList block_crypto_amend_opts_luks = { + .name = "crypto", + .head = QTAILQ_HEAD_INITIALIZER(block_crypto_create_opts_luks.head), + .desc = { + BLOCK_CRYPTO_OPT_DEF_LUKS_STATE(""), + BLOCK_CRYPTO_OPT_DEF_LUKS_KEYSLOT(""), + BLOCK_CRYPTO_OPT_DEF_LUKS_OLD_SECRET(""), + BLOCK_CRYPTO_OPT_DEF_LUKS_NEW_SECRET(""), + BLOCK_CRYPTO_OPT_DEF_LUKS_ITER_TIME(""), + { /* end of list */ } + }, +}; + QCryptoBlockOpenOptions * block_crypto_open_opts_init(QDict *opts, Error **errp) { @@ -202,6 +233,23 @@ block_crypto_create_opts_init(QDict *opts, Error **errp) return ret; } +QCryptoBlockAmendOptions * +block_crypto_amend_opts_init(QDict *opts, Error **errp) +{ + Visitor *v; + QCryptoBlockAmendOptions *ret; + + v = qobject_input_visitor_new_flat_confused(opts, errp); + if (!v) { + return NULL; + } + + visit_type_QCryptoBlockAmendOptions(v, NULL, &ret, errp); + + visit_free(v); + return ret; +} + static int block_crypto_open_generic(QCryptoBlockFormat format, QemuOptsList *opts_spec, @@ -296,8 +344,8 @@ static int block_crypto_co_create_generic(BlockDriverState *bs, }; crypto = qcrypto_block_create(opts, NULL, - block_crypto_init_func, - block_crypto_write_func, + block_crypto_create_init_func, + block_crypto_create_write_func, &data, errp); @@ -710,7 +758,6 @@ static int block_crypto_get_info_luks(BlockDriverState *bs, return ret; } - bdi->unallocated_blocks_are_zero = false; bdi->cluster_size = subbdi.cluster_size; return 0; @@ -742,6 +789,131 @@ block_crypto_get_specific_info_luks(BlockDriverState *bs, Error **errp) return spec_info; } +static int +block_crypto_amend_options_generic_luks(BlockDriverState *bs, + QCryptoBlockAmendOptions *amend_options, + bool force, + Error **errp) +{ + BlockCrypto *crypto = bs->opaque; + int ret; + + assert(crypto); + assert(crypto->block); + + /* apply for exclusive read/write permissions to the underlying file*/ + crypto->updating_keys = true; + ret = bdrv_child_refresh_perms(bs, bs->file, errp); + if (ret) { + goto cleanup; + } + + ret = qcrypto_block_amend_options(crypto->block, + block_crypto_read_func, + block_crypto_write_func, + bs, + amend_options, + force, + errp); +cleanup: + /* release exclusive read/write permissions to the underlying file*/ + crypto->updating_keys = false; + bdrv_child_refresh_perms(bs, bs->file, errp); + return ret; +} + +static int +block_crypto_amend_options_luks(BlockDriverState *bs, + QemuOpts *opts, + BlockDriverAmendStatusCB *status_cb, + void *cb_opaque, + bool force, + Error **errp) +{ + BlockCrypto *crypto = bs->opaque; + QDict *cryptoopts = NULL; + QCryptoBlockAmendOptions *amend_options = NULL; + int ret = -EINVAL; + + assert(crypto); + assert(crypto->block); + + cryptoopts = qemu_opts_to_qdict(opts, NULL); + qdict_put_str(cryptoopts, "format", "luks"); + amend_options = block_crypto_amend_opts_init(cryptoopts, errp); + qobject_unref(cryptoopts); + if (!amend_options) { + goto cleanup; + } + ret = block_crypto_amend_options_generic_luks(bs, amend_options, + force, errp); +cleanup: + qapi_free_QCryptoBlockAmendOptions(amend_options); + return ret; +} + +static int +coroutine_fn block_crypto_co_amend_luks(BlockDriverState *bs, + BlockdevAmendOptions *opts, + bool force, + Error **errp) +{ + QCryptoBlockAmendOptions amend_opts; + + amend_opts = (QCryptoBlockAmendOptions) { + .format = Q_CRYPTO_BLOCK_FORMAT_LUKS, + .u.luks = *qapi_BlockdevAmendOptionsLUKS_base(&opts->u.luks), + }; + return block_crypto_amend_options_generic_luks(bs, &amend_opts, + force, errp); +} + +static void +block_crypto_child_perms(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole role, + BlockReopenQueue *reopen_queue, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + + BlockCrypto *crypto = bs->opaque; + + bdrv_default_perms(bs, c, role, reopen_queue, perm, shared, nperm, nshared); + + /* + * For backward compatibility, manually share the write + * and resize permission + */ + *nshared |= (BLK_PERM_WRITE | BLK_PERM_RESIZE); + /* + * Since we are not fully a format driver, don't always request + * the read/resize permission but only when explicitly + * requested + */ + *nperm &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); + *nperm |= perm & (BLK_PERM_WRITE | BLK_PERM_RESIZE); + + /* + * This driver doesn't modify LUKS metadata except + * when updating the encryption slots. + * Thus unlike a proper format driver we don't ask for + * shared write/read permission. However we need it + * when we are updating the keys, to ensure that only we + * have access to the device. + * + * Encryption update will set the crypto->updating_keys + * during that period and refresh permissions + * + */ + if (crypto->updating_keys) { + /* need exclusive write access for header update */ + *nperm |= BLK_PERM_WRITE; + /* unshare read and write permission */ + *nshared &= ~(BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE); + } +} + + static const char *const block_crypto_strong_runtime_opts[] = { BLOCK_CRYPTO_OPT_LUKS_KEY_SECRET, @@ -754,13 +926,12 @@ static BlockDriver bdrv_crypto_luks = { .bdrv_probe = block_crypto_probe_luks, .bdrv_open = block_crypto_open_luks, .bdrv_close = block_crypto_close, - /* This driver doesn't modify LUKS metadata except when creating image. - * Allow share-rw=on as a special case. */ - .bdrv_child_perm = bdrv_default_perms, + .bdrv_child_perm = block_crypto_child_perms, .bdrv_co_create = block_crypto_co_create_luks, .bdrv_co_create_opts = block_crypto_co_create_opts_luks, .bdrv_co_truncate = block_crypto_co_truncate, .create_opts = &block_crypto_create_opts_luks, + .amend_opts = &block_crypto_amend_opts_luks, .bdrv_reopen_prepare = block_crypto_reopen_prepare, .bdrv_refresh_limits = block_crypto_refresh_limits, @@ -770,6 +941,8 @@ static BlockDriver bdrv_crypto_luks = { .bdrv_measure = block_crypto_measure, .bdrv_get_info = block_crypto_get_info_luks, .bdrv_get_specific_info = block_crypto_get_specific_info_luks, + .bdrv_amend_options = block_crypto_amend_options_luks, + .bdrv_co_amend = block_crypto_co_amend_luks, .is_format = true, |