Signed-off-by: Maxim Levitsky <mlevi...@redhat.com>
---
crypto/block-luks.c | 64 +++++++++++++++++++++++++++------------------
1 file changed, 38 insertions(+), 26 deletions(-)
diff --git a/crypto/block-luks.c b/crypto/block-luks.c
index 6bb369f3b4..e1a4df94b7 100644
--- a/crypto/block-luks.c
+++ b/crypto/block-luks.c
@@ -417,6 +417,33 @@ static int masterkeylen(QCryptoBlockLUKS *luks)
}
+/*
+ * Returns number of sectors needed to store the key material
+ * given number of anti forensic stripes
+ */
+static int splitkeylen_sectors(QCryptoBlockLUKS *luks, int stripes)
+
+{
+ /*
+ * This calculation doesn't match that shown in the spec,
+ * but instead follows the cryptsetup implementation.
+ */
+
+ size_t header_sectors = QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET /
+ QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
+
+ size_t splitkeylen = masterkeylen(luks) * stripes;
+
+ /* First align the key material size to block size*/
+ size_t splitkeylen_sectors =
+ DIV_ROUND_UP(splitkeylen, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE);
+
+ /* Then also align the key material size to the size of the header */
+ return ROUND_UP(splitkeylen_sectors, header_sectors);
+}
+
+
+
/*
* Stores the main LUKS header, taking care of endianess
*/
@@ -1169,7 +1196,7 @@ qcrypto_block_luks_create(QCryptoBlock *block,
QCryptoBlockCreateOptionsLUKS luks_opts;
Error *local_err = NULL;
uint8_t *masterkey = NULL;
- size_t splitkeylen = 0;
+ size_t next_sector;
size_t i;
char *password;
const char *cipher_alg;
@@ -1388,23 +1415,16 @@ qcrypto_block_luks_create(QCryptoBlock *block,
goto error;
}
+ /* start with the sector that follows the header*/
+ next_sector = QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET /
+ QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
- /* Although LUKS has multiple key slots, we're just going
- * to use the first key slot */
- splitkeylen = luks->header.key_bytes * QCRYPTO_BLOCK_LUKS_STRIPES;
for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
- luks->header.key_slots[i].active =
QCRYPTO_BLOCK_LUKS_KEY_SLOT_DISABLED;
- luks->header.key_slots[i].stripes = QCRYPTO_BLOCK_LUKS_STRIPES;
-
- /* This calculation doesn't match that shown in the spec,
- * but instead follows the cryptsetup implementation.
- */
- luks->header.key_slots[i].key_offset =
- (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET /
- QCRYPTO_BLOCK_LUKS_SECTOR_SIZE) +
- (ROUND_UP(DIV_ROUND_UP(splitkeylen,
QCRYPTO_BLOCK_LUKS_SECTOR_SIZE),
- (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET /
- QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) * i);
+ QCryptoBlockLUKSKeySlot *slot = &luks->header.key_slots[i];
+ slot->active = QCRYPTO_BLOCK_LUKS_KEY_SLOT_DISABLED;
+ slot->key_offset = next_sector;
+ slot->stripes = QCRYPTO_BLOCK_LUKS_STRIPES;
+ next_sector += splitkeylen_sectors(luks, QCRYPTO_BLOCK_LUKS_STRIPES);
}
@@ -1412,17 +1432,9 @@ qcrypto_block_luks_create(QCryptoBlock *block,
* slot headers, rounded up to the nearest sector, combined with
* the size of each master key material region, also rounded up
* to the nearest sector */
- luks->header.payload_offset =
- (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET /
- QCRYPTO_BLOCK_LUKS_SECTOR_SIZE) +
- (ROUND_UP(DIV_ROUND_UP(splitkeylen, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE),
- (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET /
- QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) *
- QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS);
-
+ luks->header.payload_offset = next_sector;
block->sector_size = QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
- block->payload_offset = luks->header.payload_offset *
- block->sector_size;
+ block->payload_offset = luks->header.payload_offset * block->sector_size;
/* Reserve header space to match payload offset */
initfunc(block, block->payload_offset, opaque, &local_err);
--
2.17.2
