Make last shred for an interrupted slot signed + typed (#6760)

core/src/broadcast_stage/standard_broadcast_run.rs

@@ -50,7 +50,7 @@ impl StandardBroadcastRun {
 
     fn check_for_interrupted_slot(&mut self) -> Option<Shred> {
         let (slot, _) = self.current_slot_and_parent.unwrap();
-        let last_unfinished_slot_shred = self
+        let mut last_unfinished_slot_shred = self
             .unfinished_slot
             .map(|last_unfinished_slot| {
                 if last_unfinished_slot.slot != slot {
@@ -70,7 +70,8 @@ impl StandardBroadcastRun {
             .unwrap_or(None);
 
         // This shred should only be Some if the previous slot was interrupted
-        if last_unfinished_slot_shred.is_some() {
+        if let Some(ref mut shred) = last_unfinished_slot_shred {
+            Shredder::sign_shred(&self.keypair, shred);
             self.unfinished_slot = None;
         }
 
@@ -331,6 +332,38 @@ mod test {
         )
     }
 
+    #[test]
+    fn test_interrupted_slot_last_shred() {
+        let keypair = Arc::new(Keypair::new());
+        let mut run = StandardBroadcastRun::new(keypair.clone());
+
+        // Set up the slot to be interrupted
+        let next_shred_index = 10;
+        let slot = 1;
+        let parent = 0;
+        run.unfinished_slot = Some(UnfinishedSlotInfo {
+            next_shred_index,
+            slot,
+            parent,
+        });
+        run.slot_broadcast_start = Some(Instant::now());
+
+        // Set up a slot to interrupt the old slot
+        run.current_slot_and_parent = Some((4, 2));
+
+        // Slot 2 interrupted slot 1
+        let shred = run
+            .check_for_interrupted_slot()
+            .expect("Expected a shred that signals an interrupt");
+
+        // Validate the shred
+        assert_eq!(shred.parent(), parent);
+        assert_eq!(shred.slot(), slot);
+        assert_eq!(shred.index(), next_shred_index);
+        assert!(shred.is_data());
+        assert!(shred.verify(&keypair.pubkey()));
+    }
+
     #[test]
     fn test_slot_interrupt() {
         // Setup
@@ -339,12 +372,12 @@ mod test {
             setup(num_shreds_per_slot);
 
         // Insert 1 less than the number of ticks needed to finish the slot
-        let ticks = create_ticks(genesis_block.ticks_per_slot - 1, 0, genesis_block.hash());
+        let ticks0 = create_ticks(genesis_block.ticks_per_slot - 1, 0, genesis_block.hash());
         let receive_results = ReceiveResults {
-            entries: ticks.clone(),
+            entries: ticks0.clone(),
             time_elapsed: Duration::new(3, 0),
             bank: bank0.clone(),
-            last_tick_height: (ticks.len() - 1) as u64,
+            last_tick_height: (ticks0.len() - 1) as u64,
         };
 
         // Step 1: Make an incomplete transmission for slot 0
@@ -362,7 +395,7 @@ mod test {
         standard_broadcast_run.stats.receive_elapsed = 10;
 
         // Try to fetch ticks from blocktree, nothing should break
-        assert_eq!(blocktree.get_slot_entries(0, 0, None).unwrap(), ticks);
+        assert_eq!(blocktree.get_slot_entries(0, 0, None).unwrap(), ticks0);
         assert_eq!(
             blocktree
                 .get_slot_entries(0, num_shreds_per_slot, None)
@@ -377,12 +410,12 @@ mod test {
         // Interrupting the slot should cause the unfinished_slot and stats to reset
         let num_shreds = 1;
         assert!(num_shreds < num_shreds_per_slot);
-        let ticks = create_ticks(max_ticks_per_n_shreds(num_shreds), 0, genesis_block.hash());
+        let ticks1 = create_ticks(max_ticks_per_n_shreds(num_shreds), 0, genesis_block.hash());
         let receive_results = ReceiveResults {
-            entries: ticks.clone(),
+            entries: ticks1.clone(),
             time_elapsed: Duration::new(2, 0),
             bank: bank2.clone(),
-            last_tick_height: (ticks.len() - 1) as u64,
+            last_tick_height: (ticks1.len() - 1) as u64,
         };
         standard_broadcast_run
             .process_receive_results(&cluster_info, &socket, &blocktree, receive_results)
@@ -394,8 +427,18 @@ mod test {
         assert_eq!(unfinished_slot.next_shred_index as u64, num_shreds);
         assert_eq!(unfinished_slot.slot, 2);
         assert_eq!(unfinished_slot.parent, 0);
+
         // Check that the stats were reset as well
         assert_eq!(standard_broadcast_run.stats.receive_elapsed, 0);
+
+        // Try to fetch the incomplete ticks from blocktree, should succeed
+        assert_eq!(blocktree.get_slot_entries(0, 0, None).unwrap(), ticks0);
+        assert_eq!(
+            blocktree
+                .get_slot_entries(0, num_shreds_per_slot, None)
+                .unwrap(),
+            vec![],
+        );
     }
 
     #[test]

ledger/src/blocktree.rs

@@ -3804,7 +3804,7 @@ pub mod tests {
                 slot,
                 next_shred_index as u32,
                 1,
-                None,
+                Some(&[1, 1, 1]),
                 true,
                 true,
             )];

ledger/src/shred.rs

@@ -160,7 +160,6 @@ impl Shred {
             data_header.flags |= LAST_SHRED_IN_SLOT
         }
 
-        if let Some(data) = data {
         let mut start = 0;
         Self::serialize_obj_into(
             &mut start,
@@ -176,6 +175,8 @@ impl Shred {
             &data_header,
         )
         .expect("Failed to write data header into shred buffer");
+
+        if let Some(data) = data {
             payload[start..start + data.len()].clone_from_slice(data);
         }