[pbs-devel] [PATCH proxmox-backup 2/4] sync: verify chunk size and digest, if possible

["Fabian Grünbichler" <f.gruenbichler@proxmox.com>]

for encrypted chunks this is currently not possible, as we need the key
to decode the chunk.

Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
---
 src/client/pull.rs                | 10 ++++++----
 src/client/remote_chunk_reader.rs |  4 ++--
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/client/pull.rs b/src/client/pull.rs
index fc193a8d..629e8266 100644
--- a/src/client/pull.rs
+++ b/src/client/pull.rs
@@ -27,16 +27,18 @@ async fn pull_index_chunks<I: IndexFile>(
 
 
     for pos in 0..index.index_count() {
-        let digest = index.index_digest(pos).unwrap();
-        let chunk_exists = target.cond_touch_chunk(digest, false)?;
+        let info = index.chunk_info(pos).unwrap();
+        let chunk_exists = target.cond_touch_chunk(&info.digest, false)?;
         if chunk_exists {
             //worker.log(format!("chunk {} exists {}", pos, proxmox::tools::digest_to_hex(digest)));
             continue;
         }
         //worker.log(format!("sync {} chunk {}", pos, proxmox::tools::digest_to_hex(digest)));
-        let chunk = chunk_reader.read_raw_chunk(&digest).await?;
+        let chunk = chunk_reader.read_raw_chunk(&info.digest).await?;
 
-        target.insert_chunk(&chunk, &digest)?;
+        chunk.verify_unencrypted(info.size() as usize, &info.digest)?;
+
+        target.insert_chunk(&chunk, &info.digest)?;
     }
 
     Ok(())
diff --git a/src/client/remote_chunk_reader.rs b/src/client/remote_chunk_reader.rs
index 4db11477..b30d0567 100644
--- a/src/client/remote_chunk_reader.rs
+++ b/src/client/remote_chunk_reader.rs
@@ -35,6 +35,8 @@ impl RemoteChunkReader {
         }
     }
 
+    /// Downloads raw chunk. This only verifies the (untrusted) CRC32, use
+    /// DataBlob::verify_unencrypted or DataBlob::decode before storing/processing further.
     pub async fn read_raw_chunk(&self, digest: &[u8; 32]) -> Result<DataBlob, Error> {
         let mut chunk_data = Vec::with_capacity(4 * 1024 * 1024);
 
@@ -43,8 +45,6 @@ impl RemoteChunkReader {
             .await?;
 
         let chunk = DataBlob::load_from_reader(&mut &chunk_data[..])?;
-        
-        // fixme: verify digest?
 
         Ok(chunk)
     }
-- 
2.20.1