Cleanup block processor flag handling

First, remove the "Don't checksum" flag, fragment blocks also need to
be checksumed and are also subject to deduplication. For sentinel
blocks, instead check if the size is zero.

Second, cleanly seperate the user settable flags from the non-user
settable flags and reject any block that has non-user settable or
unknown flags set.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

3 files changed, 18 insertions, 6 deletions

diff --git a/lib/sqfs/blk_proc/process_block.c b/lib/sqfs/blk_proc/process_block.c
index 0747bc5..5d1fa58 100644
--- a/lib/sqfs/blk_proc/process_block.c
+++ b/lib/sqfs/blk_proc/process_block.c
@@ -15,8 +15,7 @@ int sqfs_block_process(sqfs_block_t *block, sqfs_compressor_t *cmp,
 {
 	ssize_t ret;
 
-	if (!(block->flags & SQFS_BLK_DONT_CHECKSUM))
-		block->checksum = crc32(0, block->data, block->size);
+	block->checksum = crc32(0, block->data, block->size);
 
 	if (!(block->flags & SQFS_BLK_DONT_COMPRESS)) {
 		ret = cmp->do_block(cmp, block->data, block->size,
diff --git a/lib/sqfs/blk_proc/pthread.c b/lib/sqfs/blk_proc/pthread.c
index a9cffd0..f1874c0 100644
--- a/lib/sqfs/blk_proc/pthread.c
+++ b/lib/sqfs/blk_proc/pthread.c
@@ -193,12 +193,15 @@ int sqfs_block_processor_enqueue(sqfs_block_processor_t *proc,
 {
 	sqfs_block_t *queue = NULL, *it, *prev;
 
+	if (block->flags & ~SQFS_BLK_USER_SETTABLE_FLAGS)
+		return SQFS_ERROR_UNSUPPORTED;
+
 	block->sequence_number = proc->enqueue_id++;
 	block->next = NULL;
 
 	pthread_mutex_lock(&proc->mtx);
-	if ((block->flags & SQFS_BLK_DONT_COMPRESS) &&
-	    (block->flags & SQFS_BLK_DONT_CHECKSUM)) {
+	if (block->size == 0) {
+		block->checksum = 0;
 		store_completed_block(proc, block);
 	} else {
 		while (proc->backlog > proc->max_backlog)
diff --git a/lib/sqfs/blk_proc/serial.c b/lib/sqfs/blk_proc/serial.c
index b6c17fb..b7bc545 100644
--- a/lib/sqfs/blk_proc/serial.c
+++ b/lib/sqfs/blk_proc/serial.c
@@ -51,8 +51,18 @@ int sqfs_block_processor_enqueue(sqfs_block_processor_t *proc,
 		return proc->status;
 	}
 
-	proc->status = sqfs_block_process(block, proc->cmp,
-					  proc->scratch, proc->max_block_size);
+	if (block->flags & ~SQFS_BLK_USER_SETTABLE_FLAGS) {
+		proc->status = SQFS_ERROR_UNSUPPORTED;
+		return proc->status;
+	}
+
+	if (block->size == 0) {
+		block->checksum = 0;
+	} else {
+		proc->status = sqfs_block_process(block, proc->cmp,
+						  proc->scratch,
+						  proc->max_block_size);
+	}
 
 	block->next = NULL;
 	return process_completed_blocks(proc, block);