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 <berrange@redhat.com>
Message-id: 1469192015-16487-2-git-send-email-berrange@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
diff --git a/crypto/block-luks.c b/crypto/block-luks.c
index fcf3b04..aba4455 100644
--- a/crypto/block-luks.c
+++ b/crypto/block-luks.c
@@ -201,6 +201,15 @@
struct QCryptoBlockLUKS {
QCryptoBlockLUKSHeader header;
+
+ /* Cache parsed versions of what's in header fields,
+ * as we can't rely on QCryptoBlock.cipher being
+ * non-NULL */
+ QCryptoCipherAlgorithm cipher_alg;
+ QCryptoCipherMode cipher_mode;
+ QCryptoIVGenAlgorithm ivgen_alg;
+ QCryptoHashAlgorithm ivgen_hash_alg;
+ QCryptoHashAlgorithm hash_alg;
};
@@ -847,6 +856,12 @@
block->payload_offset = luks->header.payload_offset *
QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
+ luks->cipher_alg = cipheralg;
+ luks->cipher_mode = ciphermode;
+ luks->ivgen_alg = ivalg;
+ luks->ivgen_hash_alg = ivhash;
+ luks->hash_alg = hash;
+
g_free(masterkey);
g_free(password);
@@ -1271,6 +1286,12 @@
goto error;
}
+ luks->cipher_alg = luks_opts.cipher_alg;
+ luks->cipher_mode = luks_opts.cipher_mode;
+ luks->ivgen_alg = luks_opts.ivgen_alg;
+ luks->ivgen_hash_alg = luks_opts.ivgen_hash_alg;
+ luks->hash_alg = luks_opts.hash_alg;
+
memset(masterkey, 0, luks->header.key_bytes);
g_free(masterkey);
memset(slotkey, 0, luks->header.key_bytes);
@@ -1305,6 +1326,51 @@
}
+static int qcrypto_block_luks_get_info(QCryptoBlock *block,
+ QCryptoBlockInfo *info,
+ Error **errp)
+{
+ QCryptoBlockLUKS *luks = block->opaque;
+ QCryptoBlockInfoLUKSSlot *slot;
+ QCryptoBlockInfoLUKSSlotList *slots = NULL, **prev = &info->u.luks.slots;
+ size_t i;
+
+ info->u.luks.cipher_alg = luks->cipher_alg;
+ info->u.luks.cipher_mode = luks->cipher_mode;
+ info->u.luks.ivgen_alg = luks->ivgen_alg;
+ if (info->u.luks.ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
+ info->u.luks.has_ivgen_hash_alg = true;
+ info->u.luks.ivgen_hash_alg = luks->ivgen_hash_alg;
+ }
+ info->u.luks.hash_alg = luks->hash_alg;
+ info->u.luks.payload_offset = block->payload_offset;
+ info->u.luks.master_key_iters = luks->header.master_key_iterations;
+ info->u.luks.uuid = g_strndup((const char *)luks->header.uuid,
+ sizeof(luks->header.uuid));
+
+ for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
+ slots = g_new0(QCryptoBlockInfoLUKSSlotList, 1);
+ *prev = slots;
+
+ slots->value = slot = g_new0(QCryptoBlockInfoLUKSSlot, 1);
+ slot->active = luks->header.key_slots[i].active ==
+ QCRYPTO_BLOCK_LUKS_KEY_SLOT_ENABLED;
+ slot->key_offset = luks->header.key_slots[i].key_offset
+ * QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
+ if (slot->active) {
+ slot->has_iters = true;
+ slot->iters = luks->header.key_slots[i].iterations;
+ slot->has_stripes = true;
+ slot->stripes = luks->header.key_slots[i].stripes;
+ }
+
+ prev = &slots->next;
+ }
+
+ return 0;
+}
+
+
static void qcrypto_block_luks_cleanup(QCryptoBlock *block)
{
g_free(block->opaque);
@@ -1342,6 +1408,7 @@
const QCryptoBlockDriver qcrypto_block_driver_luks = {
.open = qcrypto_block_luks_open,
.create = qcrypto_block_luks_create,
+ .get_info = qcrypto_block_luks_get_info,
.cleanup = qcrypto_block_luks_cleanup,
.decrypt = qcrypto_block_luks_decrypt,
.encrypt = qcrypto_block_luks_encrypt,
