On Fri, Aug 30, 2019 at 11:56:03PM +0300, Maxim Levitsky wrote: > This implements the encryption key management > using the generic code in qcrypto layer > (currently only for qemu-img amend) > > This code adds another 'write_func' because the initialization > write_func works directly on the underlying file, > because during the creation, there is no open instance > of the luks driver, but during regular use, we have it, > and should use it instead. > > Signed-off-by: Maxim Levitsky <mlevi...@redhat.com> > --- > block/crypto.c | 106 +++++++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 103 insertions(+), 3 deletions(-) > > diff --git a/block/crypto.c b/block/crypto.c > index a6a3e1f1d8..dbd95a99ba 100644 > --- a/block/crypto.c > +++ b/block/crypto.c > @@ -36,6 +36,7 @@ typedef struct BlockCrypto BlockCrypto; > > struct BlockCrypto { > QCryptoBlock *block; > + bool updating_keys; > }; > > > @@ -70,6 +71,24 @@ 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)
Indent off-by-1 - align with param on the first line > +{ > + 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; > @@ -647,6 +666,88 @@ block_crypto_get_specific_info_luks(BlockDriverState > *bs, Error **errp) > return spec_info; > } > > + > +static int > +block_crypto_amend_options(BlockDriverState *bs, > + QemuOpts *opts, > + BlockDriverAmendStatusCB *status_cb, > + void *cb_opaque, > + bool force, > + Error **errp) > +{ > + BlockCrypto *crypto = bs->opaque; > + QDict *cryptoopts = NULL; > + QCryptoBlockCreateOptions *amend_options = NULL; > + int ret; > + > + assert(crypto); > + assert(crypto->block); > + > + crypto->updating_keys = true; > + > + ret = bdrv_child_refresh_perms(bs, bs->file, errp); > + if (ret) { I can;'t remember - does this need to be "ret < 0" or does refresh_perms return positive errnos ? > + goto cleanup; > + } > + > + cryptoopts = qemu_opts_to_qdict_filtered(opts, NULL, > + &block_crypto_create_opts_luks, > + true); > + > + qdict_put_str(cryptoopts, "format", "luks"); > + amend_options = block_crypto_create_opts_init(cryptoopts, errp); > + if (!amend_options) { > + ret = -EINVAL; > + goto cleanup; > + } > + > + ret = qcrypto_block_amend_options(crypto->block, > + block_crypto_read_func, > + block_crypto_write_func, > + bs, > + amend_options, > + force, > + errp); > +cleanup: > + crypto->updating_keys = false; > + bdrv_child_refresh_perms(bs, bs->file, errp); > + qapi_free_QCryptoBlockCreateOptions(amend_options); > + qobject_unref(cryptoopts); > + return ret; > +} > + > + > +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; > + > + /* > + * This driver doesn't modify LUKS metadata except > + * when updating the encryption slots. > + * Allow share-rw=on as a special case. > + * > + * 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 */ > + perm |= BLK_PERM_WRITE; > + shared &= ~BLK_PERM_WRITE; > + } > + > + bdrv_filter_default_perms(bs, c, role, reopen_queue, > + perm, shared, nperm, nshared); > +} > + > + > static const char *const block_crypto_strong_runtime_opts[] = { > BLOCK_CRYPTO_OPT_LUKS_KEY_SECRET, > > @@ -659,9 +760,7 @@ 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_filter_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, > @@ -674,6 +773,7 @@ static BlockDriver bdrv_crypto_luks = { > .bdrv_getlength = block_crypto_getlength, > .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, > > .strong_runtime_opts = block_crypto_strong_runtime_opts, > }; > -- > 2.17.2 > Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|