Measure pallet timeouts in relay chain blocks, not parachain blocks

client/src/challenger.rs

@@ -9,7 +9,7 @@
 //! - Automated challenge strategies
 
 use crate::base::{BaseClient, ClientConfig, ClientError, ClientResult};
-use crate::substrate::{extrinsics, storage, SubstrateClient};
+use crate::substrate::{extrinsics, fetch_current_anchor_block, storage, SubstrateClient};
 use sp_runtime::AccountId32;
 use storage_primitives::{BucketId, ChunkLocation, Commitment};
 use subxt::dynamic::At;
@@ -382,12 +382,10 @@ impl ChallengerClient {
 
         // Compute checkpoint age from bucket snapshot
         let last_checkpoint_age = {
-            let current_block = chain
-                .api()
-                .at_current_block()
-                .await
-                .map_err(|e| ClientError::Chain(format!("Failed to get latest block: {e}")))?
-                .block_number() as u32;
+            // `checkpoint_block` is on the pallet's anchor clock (relay
+            // blocks), so measure the age on that clock, not the parachain
+            // height.
+            let anchor_block = fetch_current_anchor_block(&at).await?;
 
             let (addr, keys) = storage::bucket_info(bucket_id);
             let bucket_thunk = at
@@ -413,7 +411,7 @@ impl ChallengerClient {
                     .and_then(|v| v.as_u128())
                     .unwrap_or(0) as u32;
 
-                current_block.saturating_sub(checkpoint_block)
+                anchor_block.saturating_sub(checkpoint_block)
             } else {
                 0
             }

client/src/substrate.rs

@@ -862,6 +862,30 @@ pub mod storage {
 
 // Helper functions for common operations
 
+/// The pallet's anchor block — the clock every on-chain duration is measured
+/// against — via the `StorageProviderApi::current_anchor_block` runtime API.
+/// Compare anchor-denominated values (deadlines, expiries, `checkpoint_block`)
+/// against this, never the parachain height.
+pub async fn fetch_current_anchor_block<C>(
+    at: &subxt::client::ClientAtBlock<PolkadotConfig, C>,
+) -> Result<u32, ClientError>
+where
+    C: subxt::client::OnlineClientAtBlockT<PolkadotConfig>,
+{
+    use codec::Decode;
+    // Raw `state_call` + manual decode so the API needn't be in the node's
+    // metadata snapshot.
+    let bytes = at
+        .runtime_apis()
+        .call_raw("StorageProviderApi_current_anchor_block", None)
+        .await
+        .map_err(|e| {
+            ClientError::Chain(format!("current_anchor_block runtime API call failed: {e}"))
+        })?;
+    u32::decode(&mut &bytes[..])
+        .map_err(|e| ClientError::Chain(format!("Failed to decode anchor block: {e}")))
+}
+
 /// Parse a hex string to H256.
 pub fn parse_h256(hex: &str) -> Result<H256, ClientError> {
     let hex = hex.strip_prefix("0x").unwrap_or(hex);

docs/design/EXECUTION_FLOWS.md

@@ -538,9 +538,11 @@ sequenceDiagram
     participant C as Chain (Pallet)
     participant B as Balances
 
-    Note over C: on_finalize(block_number) hook
+    Note over C: on_initialize(n) slash sweep
 
-    C->>C: expired = Challenges::take(block_number)
+    Note over C: Deadlines are relay-chain blocks. Drain every deadline key in<br/>(LastSweptChallengeBlock, previous relay parent], budget-capped.
+
+    C->>C: expired = Challenges::drain_prefix(deadline_key)
 
     loop For each expired challenge
         Note over C: Provider failed to respond!

examples/papi/checkpoint-missed.ts

@@ -26,14 +26,15 @@ import assert from "node:assert";
 import {
   configureCheckpointWindow,
   connect,
+  currentRelayBlock,
   ensureProviderRegistered,
   establishStorageAgreement,
   makeSigner,
   negotiateTerms,
   READ_OPTS,
   reportMissedCheckpoint,
   sameAddress,
-  waitForBlock,
+  waitForRelayBlock,
   waitForBlockProduction,
   waitForChainReady,
   waitForNextBlock,
@@ -107,7 +108,7 @@ async function main() {
     );
 
     console.log("\n=== Step 3: Pick a window and let it elapse without a checkpoint ===");
-    const head = Number(await api.query.System.Number.getValue(READ_OPTS));
+    const head = await currentRelayBlock(api);
     const missedWindow = BigInt(Math.floor(head / WINDOW_INTERVAL));
     // window_end = (missedWindow + 1) * interval ; need current_block > window_end
     const windowEnd = (Number(missedWindow) + 1) * WINDOW_INTERVAL;
@@ -118,7 +119,7 @@ async function main() {
       windowEnd,
       windowEnd
     );
-    await waitForBlock(papi, windowEnd);
+    await waitForRelayBlock(papi, api, windowEnd);
 
     console.log("\n=== Step 4: Record balances, then report_missed_checkpoint ===");
     const providerBefore = (await api.query.StorageProvider.Providers.getValue(

examples/papi/e2e/02-agreement-lifecycle.ts

@@ -24,7 +24,7 @@ import {
   negotiateTerms,
   READ_OPTS,
   sameAddress,
-  waitForBlock,
+  waitForRelayBlock,
 } from "@web3-storage/sdk";
 import {
   getFree,
@@ -90,7 +90,7 @@ async function main() {
       ))!;
       const expiresAt = Number(agreement.expires_at);
       console.log("    Waiting for expiry at block %d...", expiresAt);
-      await waitForBlock(papi, expiresAt);
+      await waitForRelayBlock(papi, api, expiresAt);
       const provBefore = await getFree(api, provider);
       await endAgreement(api, client, provider, bucketId, "Pay");
       const provAfter = await getFree(api, provider);
@@ -117,7 +117,7 @@ async function main() {
         READ_OPTS
       ))!;
       console.log("    Waiting for expiry at block %d...", Number(agreement.expires_at));
-      await waitForBlock(papi, Number(agreement.expires_at));
+      await waitForRelayBlock(papi, api, Number(agreement.expires_at));
       const result = await endAgreement(api, client, provider, bucketId, "Burn", {
         burn_percent: 100,
       });

examples/papi/e2e/04-data-upload-and-retrieval.ts

@@ -13,6 +13,7 @@
 import assert from "node:assert";
 import { blake2b256 } from "@polkadot-labs/hdkd-helpers";
 import {
+  currentRelayBlock,
   downloadChunk,
   ensureProviderRegistered,
   makeSigner,
@@ -55,7 +56,7 @@ async function main() {
     name: "4.1 Small chunk (100 bytes)",
     fn: async () => {
       const data = "x".repeat(100);
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       const { hash, commit } = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       assert.ok(commit.mmr_root, "Should return mmr_root");
       const downloaded = await downloadChunk(PROVIDER_URL, hash);
@@ -67,7 +68,7 @@ async function main() {
     name: "4.2 Medium chunk (64 KB)",
     fn: async () => {
       const data = randomBytes(64 * 1024);
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       const { hash } = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       const downloaded = await downloadChunk(PROVIDER_URL, hash);
       assert.deepStrictEqual(new Uint8Array(downloaded), data, "64KB roundtrip integrity");
@@ -78,7 +79,7 @@ async function main() {
     name: "4.3 Max chunk size (256 KB)",
     fn: async () => {
       const data = randomBytes(256 * 1024);
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       const { hash } = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       const downloaded = await downloadChunk(PROVIDER_URL, hash);
       assert.deepStrictEqual(new Uint8Array(downloaded), data, "256KB roundtrip integrity");
@@ -89,7 +90,7 @@ async function main() {
     name: "4.4 Multiple sequential uploads",
     fn: async () => {
       const uploads = [];
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       for (let i = 0; i < 5; i++) {
         const data = `sequential upload #${i} @ ${Date.now()}`;
         const result = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
@@ -207,7 +208,7 @@ async function main() {
     name: "4.10 Upload binary (non-UTF8) data",
     fn: async () => {
       const binary = randomBytes(512);
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       const { hash } = await uploadChunk(PROVIDER_URL, bucketId, binary, nonce);
       const downloaded = await downloadChunk(PROVIDER_URL, hash);
       assert.deepStrictEqual(new Uint8Array(downloaded), binary, "Binary roundtrip should match");
@@ -218,7 +219,7 @@ async function main() {
     name: "4.11 Upload identical content twice — different MMR leaves",
     fn: async () => {
       const data = "duplicate content for e2e";
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       const first = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       const second = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       assert.strictEqual(first.hash, second.hash, "Same data should produce same hash");
@@ -236,7 +237,7 @@ async function main() {
       const data = "verify hash computation";
       const bytes = new TextEncoder().encode(data);
       const expectedHash = toHex(blake2b256(bytes));
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       const { hash } = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       assert.strictEqual(hash, expectedHash, "Provider hash should match local blake2-256");
     },

examples/papi/e2e/05-checkpoint-and-challenges.ts

@@ -16,6 +16,7 @@ import {
   challengeOffchain,
   claimCheckpointRewards,
   configureCheckpointWindow,
+  currentRelayBlock,
   ensureProviderRegistered,
   fetchChallengeProof,
   fetchCheckpointDuty,
@@ -28,7 +29,7 @@ import {
   submitClientCheckpoint,
   submitProviderCheckpoint,
   uploadChunk,
-  waitForBlock,
+  waitForRelayBlock,
 } from "@web3-storage/sdk";
 import { ensureSoleAcceptingProvider } from "../support.js";
 import { negotiateAndEstablish, runSuite, submitTxExpectFailure, setupChain } from "./helpers.js";
@@ -57,7 +58,7 @@ async function main() {
   });
 
   const payload = `checkpoint-test @ ${Date.now()}`;
-  const uploadNonce = Number(await api.query.System.Number.getValue());
+  const uploadNonce = await currentRelayBlock(api);
   const upload = await uploadChunk(PROVIDER_URL, bucketId, payload, uploadNonce);
   const uploadInfo = {
     leafIndex: upload.commit.leaf_indices[0],
@@ -75,7 +76,7 @@ async function main() {
   tests.push({
     name: "5.1 Client checkpoint",
     fn: async () => {
-      const ckNonce = Number(await api.query.System.Number.getValue());
+      const ckNonce = await currentRelayBlock(api);
       const ck = await fetchCheckpointSignature(PROVIDER_URL, bucketId, ckNonce);
       assert.ok(ck.mmr_root, "Checkpoint should have mmr_root");
       const result = await submitClientCheckpoint(api, client, provider, bucketId, ck);
@@ -131,12 +132,12 @@ async function main() {
 
       // Compute current window with headroom.
       const HEADROOM = 8;
-      let currentBlock = Number(await api.query.System.Number.getValue(READ_OPTS));
+      let currentBlock = await currentRelayBlock(api);
       let windowNum = Math.floor(currentBlock / WINDOW_INTERVAL);
       let nextWindowStart = (windowNum + 1) * WINDOW_INTERVAL;
       if (nextWindowStart - currentBlock < HEADROOM) {
-        await waitForBlock(papi, nextWindowStart - 1);
-        currentBlock = Number(await api.query.System.Number.getValue(READ_OPTS));
+        await waitForRelayBlock(papi, api, nextWindowStart - 1);
+        currentBlock = await currentRelayBlock(api);
         windowNum = Math.floor(currentBlock / WINDOW_INTERVAL);
       }
       const window = BigInt(windowNum);

examples/papi/e2e/10-edge-cases-and-adversarial.ts

@@ -15,6 +15,7 @@ import { Enum } from "polkadot-api";
 import { blake2b256 } from "@polkadot-labs/hdkd-helpers";
 import {
   endAgreement,
+  currentRelayBlock,
   ensureProviderRegistered,
   fetchCheckpointSignature,
   freezeBucket,
@@ -24,7 +25,7 @@ import {
   submitClientCheckpoint,
   toHex,
   uploadChunk,
-  waitForBlock,
+  waitForRelayBlock,
 } from "@web3-storage/sdk";
 import { ensureSoleAcceptingProvider } from "../support.js";
 import {
@@ -108,7 +109,7 @@ async function main() {
         provider.address,
         READ_OPTS
       ))!;
-      await waitForBlock(papi, Number(agreement.expires_at));
+      await waitForRelayBlock(papi, api, Number(agreement.expires_at));
       await endAgreement(api, bob, provider, bucketId, "Pay");
       const infoAfter = (await api.query.StorageProvider.Providers.getValue(
         provider.address,
@@ -131,7 +132,7 @@ async function main() {
         duration: 100,
       });
       // freeze_bucket requires a snapshot (checkpoint) to exist.
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       await uploadChunk(PROVIDER_URL, bucketId, "data for snapshot", nonce);
       const ck = await fetchCheckpointSignature(PROVIDER_URL, bucketId, nonce);
       await submitClientCheckpoint(api, bob, provider, bucketId, ck);
@@ -153,15 +154,15 @@ async function main() {
         duration: 100,
       });
       // Upload some data.
-      const nonce1 = Number(await api.query.System.Number.getValue());
+      const nonce1 = await currentRelayBlock(api);
       await uploadChunk(PROVIDER_URL, bucketId, "pre-freeze data", nonce1);
       // Checkpoint before freeze.
       const ck1 = await fetchCheckpointSignature(PROVIDER_URL, bucketId, nonce1);
       await submitClientCheckpoint(api, bob, provider, bucketId, ck1);
       // Freeze.
       await freezeBucket(api, bob, bucketId);
       // Upload more data.
-      const nonce2 = Number(await api.query.System.Number.getValue());
+      const nonce2 = await currentRelayBlock(api);
       await uploadChunk(PROVIDER_URL, bucketId, "post-freeze data", nonce2);
       // Checkpoint after freeze — should still work (captures frozen_start_seq).
       const ck2 = await fetchCheckpointSignature(PROVIDER_URL, bucketId, nonce2);
@@ -213,7 +214,7 @@ async function main() {
       const data = "integrity check data for blake2-256";
       const bytes = new TextEncoder().encode(data);
       const expectedHash = toHex(blake2b256(bytes));
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       const { hash } = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       assert.strictEqual(hash, expectedHash, "Provider hash should match local blake2-256");
     },
@@ -227,7 +228,7 @@ async function main() {
         duration: 100,
       });
       const data = "identical content for dedup test";
-      const nonce = Number(await api.query.System.Number.getValue());
+      const nonce = await currentRelayBlock(api);
       const r1 = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       const r2 = await uploadChunk(PROVIDER_URL, bucketId, data, nonce);
       assert.strictEqual(r1.hash, r2.hash, "Hashes should match for identical content");

examples/papi/full-flow.ts

@@ -24,6 +24,7 @@ import {
   challengeCheckpoint,
   challengeOffchain,
   connect,
+  currentRelayBlock,
   downloadChunk,
   endAgreement,
   ensureProviderRegistered,
@@ -37,7 +38,7 @@ import {
   respondToChallenge,
   submitClientCheckpoint,
   uploadChunk,
-  waitForBlock,
+  waitForRelayBlock,
   waitForBlockProduction,
   waitForChainReady,
   waitForNextBlock,
@@ -65,7 +66,10 @@ async function setupAgreement(
   provider: ChainSigner
 ): Promise<bigint> {
   const maxBytes = 1_073_741_824n; // 1 GiB
-  const duration = 15;
+  // Relay-chain blocks (6s each). The relay clock keeps ticking while the
+  // parachain onboards or skips slots, so this needs headroom for steps 2-7
+  // before the step-8 expiry wait.
+  const duration = 40;
   console.log(
     "  Negotiating signed terms with provider (max_bytes=%s, duration=%d)...",
     maxBytes,
@@ -92,7 +96,7 @@ async function setupAgreement(
 
 async function uploadAndVerify(api: ParachainApi, bucketId: bigint) {
   const payload = `Hello, Web3 Storage! [${new Date().toISOString()}] provider=${PROVIDER_SEED}`;
-  const nonce = Number(await api.query.System.Number.getValue());
+  const nonce = await currentRelayBlock(api);
   const { hash, data, commit } = await uploadChunk(PROVIDER_URL, bucketId, payload, nonce);
   console.log("  Uploaded %d bytes, mmr_root=%s", data.length, commit.mmr_root);
 
@@ -129,7 +133,7 @@ async function claimPaymentAfterExpiry(api: ParachainApi, papi: PolkadotClient,
   console.log("  Provider balance before:", freeBefore.toString());
 
   console.log("  Waiting for agreement to expire...");
-  await waitForBlock(papi, expiresAt);
+  await waitForRelayBlock(papi, api, expiresAt);
   await endAgreement(api, client, provider, bucketId, "Pay");
 
   const freeAfter = (
@@ -209,7 +213,7 @@ async function main() {
     console.log("  Challenge defended");
 
     console.log("\n=== Step 5: Submit checkpoint ===");
-    const ckNonce = Number(await api.query.System.Number.getValue());
+    const ckNonce = await currentRelayBlock(api);
     const ck = await fetchCheckpointSignature(PROVIDER_URL, bucketId, ckNonce);
     console.log("  Checkpoint mmr_root:", ck.mmr_root);
     console.log("  Checkpoint leaf_count:", ck.leaf_count);