Add tickets mode to block generator

packages/jam/jamnp-s/tasks/ticket-distribution.test.ts

@@ -261,7 +261,7 @@ describe("TicketDistributionTask", () => {
     peer1.ticketTask.maintainDistribution();
     await tick();
 
-    // Self receives the ticket (via onTicketReceived -> addTicket)
+    // Self receives the ticket (via onTicketReceived -> addTicket, no callback set)
     assert.strictEqual(self.receivedTickets.length, 1);
 
     // Self should re-distribute to peer2 (and peer1, but peer1 already has it)
@@ -272,4 +272,53 @@ describe("TicketDistributionTask", () => {
     assert.strictEqual(peer2.receivedTickets.length, 1);
     assert.deepStrictEqual(peer2.receivedTickets[0].ticket, ticket);
   });
+
+  it("should NOT redistribute ticket if validation callback returns false", async () => {
+    const self = await init("self");
+    const peer1 = await init("peer1");
+    const peer2 = await init("peer2");
+
+    self.openConnection(peer1);
+    self.openConnection(peer2);
+    await tick();
+
+    // Validation always rejects
+    self.ticketTask.setOnTicketReceived(async () => false);
+
+    const ticket = createTestTicket(0);
+    peer1.ticketTask.addTicket(TEST_EPOCH, ticket);
+    peer1.ticketTask.maintainDistribution();
+    await tick();
+
+    // self.addTicket was NOT called (callback returned false), so nothing to redistribute
+    assert.strictEqual(self.receivedTickets.length, 0);
+    self.ticketTask.maintainDistribution();
+    await tick();
+    assert.strictEqual(peer2.receivedTickets.length, 0);
+  });
+
+  it("should redistribute ticket if validation callback returns true", async () => {
+    const self = await init("self");
+    const peer1 = await init("peer1");
+    const peer2 = await init("peer2");
+
+    self.openConnection(peer1);
+    self.openConnection(peer2);
+    await tick();
+
+    // Validation always accepts
+    self.ticketTask.setOnTicketReceived(async () => true);
+
+    const ticket = createTestTicket(0);
+    peer1.ticketTask.addTicket(TEST_EPOCH, ticket);
+    peer1.ticketTask.maintainDistribution();
+    await tick();
+
+    // self.addTicket WAS called (callback returned true)
+    assert.strictEqual(self.receivedTickets.length, 1);
+    self.ticketTask.maintainDistribution();
+    await tick();
+    assert.strictEqual(peer2.receivedTickets.length, 1);
+    assert.deepStrictEqual(peer2.receivedTickets[0].ticket, ticket);
+  });
 });

packages/jam/jamnp-s/tasks/ticket-distribution.ts

@@ -113,8 +113,15 @@ export class TicketDistributionTask {
    * Deduplicates tickets based on signature.
    */
   addTicket(epochIndex: Epoch, ticket: SignedTicket) {
-    // Check if epoch changed - if so, clear old tickets
-    if (this.currentEpoch !== null && this.currentEpoch !== epochIndex) {
+    // Drop tickets for older epochs (can happen when a delayed validation callback completes
+    // after the epoch has already advanced — accepting it would roll back currentEpoch).
+    if (this.currentEpoch !== null && epochIndex < this.currentEpoch) {
+      logger.warn`[addTicket] Ignoring ticket for old epoch ${epochIndex} (current: ${this.currentEpoch})`;
+      return;
+    }
+
+    // Epoch advanced — clear old tickets
+    if (this.currentEpoch !== null && epochIndex > this.currentEpoch) {
       logger.log`[addTicket] Epoch changed from ${this.currentEpoch} to ${epochIndex}, clearing ${this.pendingTickets.length} old tickets`;
       this.pendingTickets = [];
       // Note: We don't need to clear aux data for all peers here.
@@ -144,9 +151,37 @@ export class TicketDistributionTask {
     }
   }
 
+  private onTicketReceivedCallback: ((epochIndex: Epoch, ticket: SignedTicket) => Promise<boolean>) | null = null;
+
+  /**
+   * Register a callback that validates a received ticket.
+   * The ticket is only added to the redistribution pool if the callback returns `true`.
+   * This prevents redistribution of invalid tickets (e.g. those with a tampered `attempt` field).
+   */
+  setOnTicketReceived(cb: (epochIndex: Epoch, ticket: SignedTicket) => Promise<boolean>) {
+    this.onTicketReceivedCallback = cb;
+  }
+
   private onTicketReceived(epochIndex: Epoch, ticket: SignedTicket) {
     logger.trace`Received ticket for epoch ${epochIndex}, attempt ${ticket.attempt}`;
-    // Add to pending queue for potential re-distribution
-    this.addTicket(epochIndex, ticket);
+    if (this.onTicketReceivedCallback !== null) {
+      // Validate first; only redistribute if valid to avoid spreading tampered tickets.
+      // Wrap with Promise.resolve().then() to catch both sync throws and async rejections.
+      const cb = this.onTicketReceivedCallback;
+      Promise.resolve()
+        .then(() => cb(epochIndex, ticket))
+        .then((isValid) => {
+          if (isValid) {
+            this.addTicket(epochIndex, ticket);
+          } else {
+            logger.warn`Dropping invalid ticket for epoch ${epochIndex} (validation failed)`;
+          }
+        })
+        .catch((error) => {
+          logger.error`Error validating ticket for epoch ${epochIndex}, attempt ${ticket.attempt}: ${error}`;
+        });
+    } else {
+      this.addTicket(epochIndex, ticket);
+    }
   }
 }

packages/workers/block-authorship/generator.test.ts

@@ -13,11 +13,13 @@ import {
   type ValidatorIndex,
   ValidatorKeys,
 } from "@typeberry/block";
+import { SignedTicket, Ticket, tryAsTicketAttempt } from "@typeberry/block/tickets.js";
 import { Bytes, BytesBlob } from "@typeberry/bytes";
 import { asKnownSize, FixedSizeArray } from "@typeberry/collections";
 import { tinyChainSpec } from "@typeberry/config";
 import {
   BANDERSNATCH_KEY_BYTES,
+  BANDERSNATCH_PROOF_BYTES,
   BANDERSNATCH_VRF_SIGNATURE_BYTES,
   BLS_KEY_BYTES,
   ED25519_KEY_BYTES,
@@ -222,6 +224,208 @@ describe("Generator", () => {
       deepEqual(block, expectedBlock);
     });
 
+    it("should include sorted tickets during contest period", async () => {
+      // tinyChainSpec: contestLength = 10, so slot 1 is in contest period (1 < 10)
+      const state = createMockState(0);
+      const blocksDb = createMockBlocksDb(MOCK_PARENT_HASH);
+      const statesDb = createMockStatesDb(state);
+
+      const generator = new Generator(tinyChainSpec, bandersnatch, keccakHasher, blake2b, blocksDb, statesDb);
+
+      // Create two tickets with different signatures
+      const sig1 = Bytes.zero(BANDERSNATCH_PROOF_BYTES);
+      sig1.raw[0] = 1;
+      const sig2 = Bytes.zero(BANDERSNATCH_PROOF_BYTES);
+      sig2.raw[0] = 2;
+
+      const ticket1 = SignedTicket.create({
+        attempt: tryAsTicketAttempt(0),
+        signature: sig1.asOpaque(),
+      });
+      const ticket2 = SignedTicket.create({
+        attempt: tryAsTicketAttempt(0),
+        signature: sig2.asOpaque(),
+      });
+
+      // ticket2 gets smaller ID (0x01...) and ticket1 gets larger ID (0x02...)
+      // so the sorted order should be [ticket2, ticket1]
+      const id1 = Bytes.fill(HASH_SIZE, 0x02).asOpaque<EntropyHash>();
+      const id2 = Bytes.fill(HASH_SIZE, 0x01).asOpaque<EntropyHash>();
+
+      const validatorIndex = tryAsValidatorIndex(0);
+      // Slot 1 is in contest period (1 < contestLength=10)
+      const timeSlot = tryAsTimeSlot(1);
+
+      // IDs are now pre-computed before passing to nextBlock
+      const block = await generator.nextBlock(validatorIndex, MOCK_BANDERSNATCH_SECRET, MOCK_SEAL_PAYLOAD, timeSlot, [
+        { ticket: ticket1, id: id1 },
+        { ticket: ticket2, id: id2 },
+      ]);
+
+      // Tickets should be sorted by ID ascending: ticket2 (id=0x01) before ticket1 (id=0x02)
+      const tickets = block.extrinsic.tickets as unknown as SignedTicket[];
+      deepEqual(tickets.length, 2);
+      deepEqual(tickets[0].signature, sig2.asOpaque());
+      deepEqual(tickets[1].signature, sig1.asOpaque());
+    });
+
+    it("should exclude tickets outside contest period", async () => {
+      // tinyChainSpec: contestLength = 10, epochLength = 12
+      // Slot 10 is outside contest period (10 >= 10)
+      const state = createMockState(9);
+      const blocksDb = createMockBlocksDb(MOCK_PARENT_HASH);
+      const statesDb = createMockStatesDb(state);
+
+      const generator = new Generator(tinyChainSpec, bandersnatch, keccakHasher, blake2b, blocksDb, statesDb);
+
+      const sig1 = Bytes.zero(BANDERSNATCH_PROOF_BYTES);
+      const ticket1 = SignedTicket.create({
+        attempt: tryAsTicketAttempt(0),
+        signature: sig1.asOpaque(),
+      });
+
+      const validatorIndex = tryAsValidatorIndex(0);
+      // Slot 10 is NOT in contest period (10 >= contestLength=10)
+      const timeSlot = tryAsTimeSlot(10);
+
+      const mockId = Bytes.fill(HASH_SIZE, 0x01).asOpaque<EntropyHash>();
+      const block = await generator.nextBlock(validatorIndex, MOCK_BANDERSNATCH_SECRET, MOCK_SEAL_PAYLOAD, timeSlot, [
+        { ticket: ticket1, id: mockId },
+      ]);
+
+      // No tickets should be included outside contest period
+      const tickets = block.extrinsic.tickets as unknown as SignedTicket[];
+      deepEqual(tickets.length, 0);
+    });
+
+    it("should filter out tickets already in ticketsAccumulator", async () => {
+      // Build a state that already has ticket with id=0x01 in its accumulator
+      const accumulatedId = Bytes.fill(HASH_SIZE, 0x01).asOpaque<EntropyHash>();
+      const accumulatedTicket = Ticket.create({
+        id: accumulatedId,
+        attempt: tryAsTicketAttempt(0),
+      });
+
+      const state = {
+        ...createMockState(0),
+        ticketsAccumulator: asKnownSize([accumulatedTicket]),
+      };
+      const blocksDb = createMockBlocksDb(MOCK_PARENT_HASH);
+      const statesDb = createMockStatesDb(state);
+
+      const generator = new Generator(tinyChainSpec, bandersnatch, keccakHasher, blake2b, blocksDb, statesDb);
+
+      const sig1 = Bytes.zero(BANDERSNATCH_PROOF_BYTES);
+      sig1.raw[0] = 1;
+      const sig2 = Bytes.zero(BANDERSNATCH_PROOF_BYTES);
+      sig2.raw[0] = 2;
+
+      const ticketAlreadyAccumulated = SignedTicket.create({
+        attempt: tryAsTicketAttempt(0),
+        signature: sig1.asOpaque(),
+      });
+      const ticketNew = SignedTicket.create({
+        attempt: tryAsTicketAttempt(0),
+        signature: sig2.asOpaque(),
+      });
+
+      // id=0x01 is already in accumulator, id=0x02 is new
+      const idAccumulated = Bytes.fill(HASH_SIZE, 0x01).asOpaque<EntropyHash>();
+      const idNew = Bytes.fill(HASH_SIZE, 0x02).asOpaque<EntropyHash>();
+
+      const validatorIndex = tryAsValidatorIndex(0);
+      const timeSlot = tryAsTimeSlot(1); // inside contest period
+
+      const block = await generator.nextBlock(validatorIndex, MOCK_BANDERSNATCH_SECRET, MOCK_SEAL_PAYLOAD, timeSlot, [
+        { ticket: ticketAlreadyAccumulated, id: idAccumulated },
+        { ticket: ticketNew, id: idNew },
+      ]);
+
+      // Only the new ticket (not in accumulator) should be included
+      const tickets = block.extrinsic.tickets as unknown as SignedTicket[];
+      deepEqual(tickets.length, 1);
+      deepEqual(tickets[0].signature, sig2.asOpaque());
+    });
+
+    it("should deduplicate tickets by ID", async () => {
+      const state = createMockState(0);
+      const blocksDb = createMockBlocksDb(MOCK_PARENT_HASH);
+      const statesDb = createMockStatesDb(state);
+
+      const generator = new Generator(tinyChainSpec, bandersnatch, keccakHasher, blake2b, blocksDb, statesDb);
+
+      const sig1 = Bytes.zero(BANDERSNATCH_PROOF_BYTES);
+      sig1.raw[0] = 1;
+      const sig2 = Bytes.zero(BANDERSNATCH_PROOF_BYTES);
+      sig2.raw[0] = 2;
+
+      // Two different SignedTicket objects but with the same ID (e.g. duplicate from reorg)
+      const ticketA = SignedTicket.create({
+        attempt: tryAsTicketAttempt(0),
+        signature: sig1.asOpaque(),
+      });
+      const ticketB = SignedTicket.create({
+        attempt: tryAsTicketAttempt(0),
+        signature: sig2.asOpaque(),
+      });
+      const duplicateId = Bytes.fill(HASH_SIZE, 0x05).asOpaque<EntropyHash>();
+
+      const validatorIndex = tryAsValidatorIndex(0);
+      const timeSlot = tryAsTimeSlot(1);
+
+      const block = await generator.nextBlock(validatorIndex, MOCK_BANDERSNATCH_SECRET, MOCK_SEAL_PAYLOAD, timeSlot, [
+        { ticket: ticketA, id: duplicateId },
+        { ticket: ticketB, id: duplicateId }, // same ID — should be deduplicated
+      ]);
+
+      const tickets = block.extrinsic.tickets as unknown as SignedTicket[];
+      deepEqual(tickets.length, 1);
+      // First occurrence is kept after sort (both have same ID, ticketA comes first)
+      deepEqual(tickets[0].signature, sig1.asOpaque());
+    });
+
+    it("should include at most maxTicketsPerExtrinsic tickets", async () => {
+      // tinyChainSpec.maxTicketsPerExtrinsic = 3
+      const state = createMockState(0);
+      const blocksDb = createMockBlocksDb(MOCK_PARENT_HASH);
+      const statesDb = createMockStatesDb(state);
+
+      const generator = new Generator(tinyChainSpec, bandersnatch, keccakHasher, blake2b, blocksDb, statesDb);
+
+      // Create 4 tickets — only 3 should be included (lowest IDs win)
+      const makeTicket = (sigByte: number, idByte: number) => {
+        const sig = Bytes.zero(BANDERSNATCH_PROOF_BYTES);
+        sig.raw[0] = sigByte;
+        return {
+          ticket: SignedTicket.create({ attempt: tryAsTicketAttempt(0), signature: sig.asOpaque() }),
+          id: Bytes.fill(HASH_SIZE, idByte).asOpaque<EntropyHash>(),
+          sig: sig.asOpaque(),
+        };
+      };
+
+      const t1 = makeTicket(1, 0x01); // lowest ID
+      const t2 = makeTicket(2, 0x02);
+      const t3 = makeTicket(3, 0x03);
+      const t4 = makeTicket(4, 0x04); // highest ID — should be excluded
+
+      const validatorIndex = tryAsValidatorIndex(0);
+      const timeSlot = tryAsTimeSlot(1);
+
+      const block = await generator.nextBlock(validatorIndex, MOCK_BANDERSNATCH_SECRET, MOCK_SEAL_PAYLOAD, timeSlot, [
+        { ticket: t4.ticket, id: t4.id }, // pass out-of-order to verify sorting
+        { ticket: t2.ticket, id: t2.id },
+        { ticket: t3.ticket, id: t3.id },
+        { ticket: t1.ticket, id: t1.id },
+      ]);
+
+      const tickets = block.extrinsic.tickets as unknown as SignedTicket[];
+      deepEqual(tickets.length, 3); // maxTicketsPerExtrinsic = 3
+      // Should include the 3 lowest IDs, sorted ascending
+      deepEqual(tickets[0].signature, t1.sig);
+      deepEqual(tickets[1].signature, t2.sig);
+      deepEqual(tickets[2].signature, t3.sig);
+    });
+
     it("should create block with epoch marker at epoch boundary", async () => {
       // tinyChainSpec.epochLength = 12, so:
       // - timeslot 11 is last slot of epoch 0