hides implementation details of shred from its public interface

Working towards embedding versioning into shreds binary, so that a new
variant of shred struct can include merkle tree hashes of the erasure
set.

core/benches/cluster_nodes.rs

@@ -37,7 +37,7 @@ fn get_retransmit_peers_deterministic(
     num_simulated_shreds: usize,
 ) {
     for i in 0..num_simulated_shreds {
-        shred.common_header.index = i as u32;
+        shred.set_index(i as u32);
         let (_neighbors, _children) = cluster_nodes.get_retransmit_peers(
             *slot_leader,
             shred,
@@ -55,7 +55,7 @@ fn get_retransmit_peers_deterministic_wrapper(b: &mut Bencher, unstaked_ratio: O
     let slot_leader = nodes[1..].choose(&mut rng).unwrap().id;
     let slot = rand::random::<u64>();
     let mut shred = Shred::new_empty_data_shred();
-    shred.common_header.slot = slot;
+    shred.set_slot(slot);
     b.iter(|| {
         get_retransmit_peers_deterministic(
             &cluster_nodes,

core/benches/shredder.rs

@@ -9,14 +9,21 @@ use {
     solana_entry::entry::{create_ticks, Entry},
     solana_ledger::shred::{
         max_entries_per_n_shred, max_ticks_per_n_shreds, ProcessShredsStats, Shred, Shredder,
-        MAX_DATA_SHREDS_PER_FEC_BLOCK, SHRED_PAYLOAD_SIZE, SIZE_OF_CODING_SHRED_HEADERS,
-        SIZE_OF_DATA_SHRED_PAYLOAD,
+        MAX_DATA_SHREDS_PER_FEC_BLOCK, SIZE_OF_DATA_SHRED_PAYLOAD,
     },
     solana_perf::test_tx,
-    solana_sdk::{hash::Hash, signature::Keypair},
+    solana_sdk::{hash::Hash, packet::PACKET_DATA_SIZE, signature::Keypair},
     test::Bencher,
 };
 
+// Copied these values here to avoid exposing shreds
+// internals only for the sake of benchmarks.
+
+// size of nonce: 4
+// size of common shred header: 83
+// size of coding shred header: 6
+const VALID_SHRED_DATA_LEN: usize = PACKET_DATA_SIZE - 4 - 83 - 6;
+
 fn make_test_entry(txs_per_entry: u64) -> Entry {
     Entry {
         num_hashes: 100_000,
@@ -54,11 +61,10 @@ fn make_shreds(num_shreds: usize) -> Vec<Shred> {
 
 fn make_concatenated_shreds(num_shreds: usize) -> Vec<u8> {
     let data_shreds = make_shreds(num_shreds);
-    let valid_shred_data_len = (SHRED_PAYLOAD_SIZE - SIZE_OF_CODING_SHRED_HEADERS) as usize;
-    let mut data: Vec<u8> = vec![0; num_shreds * valid_shred_data_len];
+    let mut data: Vec<u8> = vec![0; num_shreds * VALID_SHRED_DATA_LEN];
     for (i, shred) in (data_shreds[0..num_shreds]).iter().enumerate() {
-        data[i * valid_shred_data_len..(i + 1) * valid_shred_data_len]
-            .copy_from_slice(&shred.payload[..valid_shred_data_len]);
+        data[i * VALID_SHRED_DATA_LEN..(i + 1) * VALID_SHRED_DATA_LEN]
+            .copy_from_slice(&shred.payload()[..VALID_SHRED_DATA_LEN]);
     }
 
     data
@@ -120,7 +126,7 @@ fn bench_deserialize_hdr(bencher: &mut Bencher) {
     let shred = Shred::new_from_data(2, 1, 1, Some(&data), true, true, 0, 0, 1);
 
     bencher.iter(|| {
-        let payload = shred.payload.clone();
+        let payload = shred.payload().clone();
         let _ = Shred::new_from_serialized_shred(payload).unwrap();
     })
 }
@@ -157,9 +163,8 @@ fn bench_shredder_decoding(bencher: &mut Bencher) {
 fn bench_shredder_coding_raptorq(bencher: &mut Bencher) {
     let symbol_count = MAX_DATA_SHREDS_PER_FEC_BLOCK;
     let data = make_concatenated_shreds(symbol_count as usize);
-    let valid_shred_data_len = (SHRED_PAYLOAD_SIZE - SIZE_OF_CODING_SHRED_HEADERS) as usize;
     bencher.iter(|| {
-        let encoder = Encoder::with_defaults(&data, valid_shred_data_len as u16);
+        let encoder = Encoder::with_defaults(&data, VALID_SHRED_DATA_LEN as u16);
         encoder.get_encoded_packets(symbol_count);
     })
 }
@@ -168,8 +173,7 @@ fn bench_shredder_coding_raptorq(bencher: &mut Bencher) {
 fn bench_shredder_decoding_raptorq(bencher: &mut Bencher) {
     let symbol_count = MAX_DATA_SHREDS_PER_FEC_BLOCK;
     let data = make_concatenated_shreds(symbol_count as usize);
-    let valid_shred_data_len = (SHRED_PAYLOAD_SIZE - SIZE_OF_CODING_SHRED_HEADERS) as usize;
-    let encoder = Encoder::with_defaults(&data, valid_shred_data_len as u16);
+    let encoder = Encoder::with_defaults(&data, VALID_SHRED_DATA_LEN as u16);
     let mut packets = encoder.get_encoded_packets(symbol_count as u32);
     packets.shuffle(&mut rand::thread_rng());
 

core/src/broadcast_stage.rs

@@ -424,7 +424,7 @@ pub fn broadcast_shreds(
             update_peer_stats(&cluster_nodes, last_datapoint_submit);
             let root_bank = root_bank.clone();
             shreds.flat_map(move |shred| {
-                repeat(&shred.payload).zip(cluster_nodes.get_broadcast_addrs(
+                repeat(shred.payload()).zip(cluster_nodes.get_broadcast_addrs(
                     shred,
                     &root_bank,
                     DATA_PLANE_FANOUT,

core/src/broadcast_stage/broadcast_duplicates_run.rs

@@ -325,13 +325,13 @@ impl BroadcastRun for BroadcastDuplicatesRun {
                             .filter_map(|pubkey| {
                                 let tvu = cluster_info
                                     .lookup_contact_info(pubkey, |contact_info| contact_info.tvu)?;
-                                Some((&shred.payload, tvu))
+                                Some((shred.payload(), tvu))
                             })
                             .collect(),
                     );
                 }
 
-                Some(vec![(&shred.payload, node.tvu)])
+                Some(vec![(shred.payload(), node.tvu)])
             })
             .flatten()
             .collect();

core/src/broadcast_stage/broadcast_fake_shreds_run.rs

@@ -132,7 +132,7 @@ impl BroadcastRun for BroadcastFakeShredsRun {
                 if fake == (i <= self.partition) {
                     // Send fake shreds to the first N peers
                     data_shreds.iter().for_each(|b| {
-                        sock.send_to(&b.payload, &peer.tvu_forwards).unwrap();
+                        sock.send_to(b.payload(), &peer.tvu_forwards).unwrap();
                     });
                 }
             });

core/src/packet_hasher.rs

@@ -31,7 +31,7 @@ impl PacketHasher {
     }
 
     pub(crate) fn hash_shred(&self, shred: &Shred) -> u64 {
-        self.hash_data(&shred.payload)
+        self.hash_data(shred.payload())
     }
 
     fn hash_data(&self, data: &[u8]) -> u64 {

core/src/repair_response.rs

@@ -79,10 +79,10 @@ mod test {
         assert_eq!(shred.slot(), slot);
         let keypair = Keypair::new();
         shred.sign(&keypair);
-        trace!("signature {}", shred.common_header.signature);
+        trace!("signature {}", shred.signature());
         let nonce = 9;
         let mut packet = repair_response_packet_from_bytes(
-            shred.payload,
+            shred.into_payload(),
             &SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080),
             nonce,
         )

core/src/replay_stage.rs

@@ -3133,10 +3133,7 @@ pub mod tests {
             create_new_tmp_ledger,
             genesis_utils::{create_genesis_config, create_genesis_config_with_leader},
             get_tmp_ledger_path,
-            shred::{
-                CodingShredHeader, DataShredHeader, Shred, ShredCommonHeader, DATA_COMPLETE_SHRED,
-                SIZE_OF_COMMON_SHRED_HEADER, SIZE_OF_DATA_SHRED_HEADER, SIZE_OF_DATA_SHRED_PAYLOAD,
-            },
+            shred::{Shred, SIZE_OF_DATA_SHRED_PAYLOAD},
         },
         solana_rpc::{
             optimistically_confirmed_bank_tracker::OptimisticallyConfirmedBank,
@@ -3152,7 +3149,6 @@ pub mod tests {
             genesis_config,
             hash::{hash, Hash},
             instruction::InstructionError,
-            packet::PACKET_DATA_SIZE,
             poh_config::PohConfig,
             signature::{Keypair, Signer},
             system_transaction,
@@ -3736,26 +3732,19 @@ pub mod tests {
     fn test_dead_fork_entry_deserialize_failure() {
         // Insert entry that causes deserialization failure
         let res = check_dead_fork(|_, bank| {
-            let gibberish = [0xa5u8; PACKET_DATA_SIZE];
-            let mut data_header = DataShredHeader::default();
-            data_header.flags |= DATA_COMPLETE_SHRED;
-            // Need to provide the right size for Shredder::deshred.
-            data_header.size = SIZE_OF_DATA_SHRED_PAYLOAD as u16;
-            data_header.parent_offset = (bank.slot() - bank.parent_slot()) as u16;
-            let shred_common_header = ShredCommonHeader {
-                slot: bank.slot(),
-                ..ShredCommonHeader::default()
-            };
-            let mut shred = Shred::new_empty_from_header(
-                shred_common_header,
-                data_header,
-                CodingShredHeader::default(),
+            let gibberish = [0xa5u8; SIZE_OF_DATA_SHRED_PAYLOAD];
+            let parent_offset = bank.slot() - bank.parent_slot();
+            let shred = Shred::new_from_data(
+                bank.slot(),
+                0, // index,
+                parent_offset as u16,
+                Some(&gibberish),
+                true,  // is_last_data
+                false, // is_last_in_slot
+                0,     // reference_tick
+                0,     // version
+                0,     // fec_set_index
             );
-            bincode::serialize_into(
-                &mut shred.payload[SIZE_OF_COMMON_SHRED_HEADER + SIZE_OF_DATA_SHRED_HEADER..],
-                &gibberish[..SIZE_OF_DATA_SHRED_PAYLOAD],
-            )
-            .unwrap();
             vec![shred]
         });
 

core/src/retransmit_stage.rs

@@ -295,7 +295,7 @@ fn retransmit(
             .fetch_add(compute_turbine_peers.as_us(), Ordering::Relaxed);
 
         let mut retransmit_time = Measure::start("retransmit_to");
-        let num_nodes = match multi_target_send(socket, &shred.payload, &addrs) {
+        let num_nodes = match multi_target_send(socket, shred.payload(), &addrs) {
             Ok(()) => addrs.len(),
             Err(SendPktsError::IoError(ioerr, num_failed)) => {
                 stats

core/src/serve_repair.rs

@@ -1095,11 +1095,12 @@ mod tests {
             // Create slots [1, 2] with 1 shred apiece
             let (mut shreds, _) = make_many_slot_entries(1, 2, 1);
 
-            // Make shred for slot 1 too large
             assert_eq!(shreds[0].slot(), 1);
             assert_eq!(shreds[0].index(), 0);
-            shreds[0].payload.push(10);
-            shreds[0].data_header.size = shreds[0].payload.len() as u16;
+            // TODO: The test previously relied on corrupting shred payload
+            // size which we no longer want to expose. Current test no longer
+            // covers packet size check in repair_response_packet_from_bytes.
+            shreds.remove(0);
             blockstore
                 .insert_shreds(shreds, None, false)
                 .expect("Expect successful ledger write");

core/src/sigverify_shreds.rs

@@ -94,8 +94,8 @@ pub mod tests {
         let keypair = Keypair::new();
         shred.sign(&keypair);
         batches[0].packets.resize(1, Packet::default());
-        batches[0].packets[0].data[0..shred.payload.len()].copy_from_slice(&shred.payload);
-        batches[0].packets[0].meta.size = shred.payload.len();
+        batches[0].packets[0].data[0..shred.payload().len()].copy_from_slice(shred.payload());
+        batches[0].packets[0].meta.size = shred.payload().len();
 
         let mut shred = Shred::new_from_data(
             0xc0de_dead,
@@ -110,8 +110,8 @@ pub mod tests {
         );
         shred.sign(&keypair);
         batches[1].packets.resize(1, Packet::default());
-        batches[1].packets[0].data[0..shred.payload.len()].copy_from_slice(&shred.payload);
-        batches[1].packets[0].meta.size = shred.payload.len();
+        batches[1].packets[0].data[0..shred.payload().len()].copy_from_slice(shred.payload());
+        batches[1].packets[0].meta.size = shred.payload().len();
 
         let expected: HashSet<u64> = [0xc0de_dead, 0xdead_c0de].iter().cloned().collect();
         assert_eq!(ShredSigVerifier::read_slots(&batches), expected);
@@ -143,8 +143,8 @@ pub mod tests {
             0xc0de,
         );
         shred.sign(&leader_keypair);
-        batches[0].packets[0].data[0..shred.payload.len()].copy_from_slice(&shred.payload);
-        batches[0].packets[0].meta.size = shred.payload.len();
+        batches[0].packets[0].data[0..shred.payload().len()].copy_from_slice(shred.payload());
+        batches[0].packets[0].meta.size = shred.payload().len();
 
         let mut shred = Shred::new_from_data(
             0,
@@ -159,8 +159,8 @@ pub mod tests {
         );
         let wrong_keypair = Keypair::new();
         shred.sign(&wrong_keypair);
-        batches[0].packets[1].data[0..shred.payload.len()].copy_from_slice(&shred.payload);
-        batches[0].packets[1].meta.size = shred.payload.len();
+        batches[0].packets[1].data[0..shred.payload().len()].copy_from_slice(shred.payload());
+        batches[0].packets[1].meta.size = shred.payload().len();
 
         let num_packets = solana_perf::sigverify::count_packets_in_batches(&batches);
         let rv = verifier.verify_batches(batches, num_packets);

core/src/window_service.rs

@@ -193,8 +193,8 @@ pub(crate) fn should_retransmit_and_persist(
         } else if shred.index() >= MAX_DATA_SHREDS_PER_SLOT as u32 {
             inc_new_counter_warn!("streamer-recv_window-shred_index_overrun", 1);
             false
-        } else if shred.data_header.size as usize > shred.payload.len() {
-            inc_new_counter_warn!("streamer-recv_window-shred_bad_meta_size", 1);
+        } else if !shred.sanitize() {
+            inc_new_counter_warn!("streamer-recv_window-invalid-shred", 1);
             false
         } else {
             true
@@ -215,13 +215,13 @@ fn run_check_duplicate(
         let shred_slot = shred.slot();
         if !blockstore.has_duplicate_shreds_in_slot(shred_slot) {
             if let Some(existing_shred_payload) =
-                blockstore.is_shred_duplicate(shred.id(), shred.payload.clone())
+                blockstore.is_shred_duplicate(shred.id(), shred.payload().clone())
             {
                 cluster_info.push_duplicate_shred(&shred, &existing_shred_payload)?;
                 blockstore.store_duplicate_slot(
                     shred_slot,
                     existing_shred_payload,
-                    shred.payload,
+                    shred.into_payload(),
                 )?;
 
                 duplicate_slot_sender.send(shred_slot)?;
@@ -717,7 +717,7 @@ mod test {
             blockstore::{make_many_slot_entries, Blockstore},
             genesis_utils::create_genesis_config_with_leader,
             get_tmp_ledger_path,
-            shred::{DataShredHeader, Shredder},
+            shred::Shredder,
         },
         solana_sdk::{
             epoch_schedule::MINIMUM_SLOTS_PER_EPOCH,
@@ -825,21 +825,9 @@ mod test {
             0
         ));
 
-        // with a bad header size
-        let mut bad_header_shred = shreds[0].clone();
-        bad_header_shred.data_header.size = (bad_header_shred.payload.len() + 1) as u16;
-        assert!(!should_retransmit_and_persist(
-            &bad_header_shred,
-            Some(bank.clone()),
-            &cache,
-            &me_id,
-            0,
-            0
-        ));
-
         // with an invalid index, shred gets thrown out
         let mut bad_index_shred = shreds[0].clone();
-        bad_index_shred.common_header.index = (MAX_DATA_SHREDS_PER_SLOT + 1) as u32;
+        bad_index_shred.set_index((MAX_DATA_SHREDS_PER_SLOT + 1) as u32);
         assert!(!should_retransmit_and_persist(
             &bad_index_shred,
             Some(bank.clone()),
@@ -875,7 +863,7 @@ mod test {
         ));
 
         // coding shreds don't contain parent slot information, test that slot >= root
-        let (common, coding) = Shred::new_coding_shred_header(
+        let mut coding_shred = Shred::new_empty_coding(
             5, // slot
             5, // index
             5, // fec_set_index
@@ -884,8 +872,6 @@ mod test {
             3, // position
             0, // version
         );
-        let mut coding_shred =
-            Shred::new_empty_from_header(common, DataShredHeader::default(), coding);
         coding_shred.sign(&leader_keypair);
         // shred.slot() > root, shred continues
         assert!(should_retransmit_and_persist(
@@ -959,7 +945,7 @@ mod test {
             std::net::{IpAddr, Ipv4Addr},
         };
         solana_logger::setup();
-        let (common, coding) = Shred::new_coding_shred_header(
+        let shred = Shred::new_empty_coding(
             5, // slot
             5, // index
             5, // fec_set_index
@@ -968,7 +954,6 @@ mod test {
             4, // position
             0, // version
         );
-        let shred = Shred::new_empty_from_header(common, DataShredHeader::default(), coding);
         let mut shreds = vec![shred.clone(), shred.clone(), shred];
         let _from_addr = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080);
         let repair_meta = RepairMeta {

gossip/src/cluster_info.rs

@@ -3343,9 +3343,12 @@ mod tests {
         let keypair = Keypair::new();
         let (slot, parent_slot, reference_tick, version) = (53084024, 53084023, 0, 0);
         let shredder = Shredder::new(slot, parent_slot, reference_tick, version).unwrap();
-        let next_shred_index = rng.gen();
+        let next_shred_index = rng.gen_range(0, 32_000);
         let shred = new_rand_shred(&mut rng, next_shred_index, &shredder, &leader);
-        let other_payload = new_rand_shred(&mut rng, next_shred_index, &shredder, &leader).payload;
+        let other_payload = {
+            let other_shred = new_rand_shred(&mut rng, next_shred_index, &shredder, &leader);
+            other_shred.into_payload()
+        };
         let leader_schedule = |s| {
             if s == slot {
                 Some(leader.pubkey())