watcher: solana shim support

Author: panoel

package-lock.json

@@ -45,6 +45,7 @@
     "algosdk": "^2.4.0",
     "anchor-0.29.0": "npm:@coral-xyz/anchor@^0.29.0",
     "aptos": "^1.4.0",
+    "binary-layout": "^1.2.0",
     "bs58": "^5.0.0",
     "dotenv": "^16.0.3",
     "firebase-admin": "^11.4.0",

watcher/package.json

@@ -18,16 +18,37 @@ import {
   universalAddress_stripped,
 } from '@wormhole-foundation/wormhole-monitor-common';
 import { Watcher } from './Watcher';
-import { Network, contracts } from '@wormhole-foundation/sdk-base';
+import { Network, contracts, encoding } from '@wormhole-foundation/sdk-base';
 import { deserializePostMessage } from '@wormhole-foundation/sdk-solana-core';
 import { getAllKeys } from '../utils/solana';
+import { UniversalAddress } from '@wormhole-foundation/sdk-definitions';
+import { DeriveType, deserialize, Layout } from 'binary-layout';
 
 const COMMITMENT: Commitment = 'finalized';
 const GET_SIGNATURES_LIMIT = 1000;
 
+const ShimContracts: { [key in Network]: string } = {
+  Mainnet: '',
+  Testnet: 'EtZMZM22ViKMo4r5y4Anovs3wKQ2owUmDpjygnMMcdEX',
+  Devnet: '',
+};
+
+const POST_MESSAGE_INSTRUCTION_ID = 0x01;
+const POST_MESSAGE_UNRELIABLE_INSTRUCTION_ID = 0x08;
+const shimMessageEventDiscriminator = 'e445a52e51cb9a1d441b8f004d4c8970';
+
+const shimMessageEventLayout = [
+  { name: 'discriminator', binary: 'bytes', size: 16 },
+  { name: 'emitterAddress', binary: 'bytes', size: 32 },
+  { name: 'sequence', binary: 'uint', size: 8, endianness: 'little' },
+  { name: 'timestamp', binary: 'uint', size: 4, endianness: 'little' },
+] as const satisfies Layout;
+export type ShimMessageEvent = DeriveType<typeof shimMessageEventLayout>;
+
 export class SolanaWatcher extends Watcher {
   readonly rpc: string;
   readonly programId: string;
+  readonly shimProgramId: string;
   // this is set as a class field so we can modify it in tests
   getSignaturesLimit = GET_SIGNATURES_LIMIT;
   // The Solana watcher uses the `getSignaturesForAddress` RPC endpoint to fetch all transactions
@@ -43,6 +64,7 @@ export class SolanaWatcher extends Watcher {
     super(network, 'Solana', mode);
     this.rpc = RPCS_BY_CHAIN[this.network].Solana!;
     this.programId = contracts.coreBridge(this.network, 'Solana');
+    this.shimProgramId = ShimContracts[this.network];
   }
 
   getConnection(): Connection {
@@ -162,39 +184,75 @@ export class SolanaWatcher extends Watcher {
 
         const accountKeys = await getAllKeys(this.getConnection(), res);
         const programIdIndex = accountKeys.findIndex((i) => i.toBase58() === this.programId);
+        const shimProgramIdIndex = accountKeys.findIndex(
+          (i) => i.toBase58() === this.shimProgramId
+        );
         const message: VersionedMessage = res.transaction.message;
         const instructions = message.compiledInstructions;
         const innerInstructions =
           res.meta?.innerInstructions?.flatMap((i) =>
             i.instructions.map(normalizeCompileInstruction)
           ) || [];
 
+        // Need to look for Wormhole instructions and shim instructions
         const whInstructions = innerInstructions
           .concat(instructions)
-          .filter((i) => i.programIdIndex === programIdIndex);
+          .filter(
+            (i) => i.programIdIndex === programIdIndex || i.programIdIndex === shimProgramIdIndex
+          );
 
         const blockKey = makeBlockKey(
           res.slot.toString(),
           new Date(res.blockTime * 1000).toISOString()
         );
 
+        let needShim = false;
+        let gotShim = false;
         const vaaKeys: string[] = [];
         for (const instruction of whInstructions) {
-          // skip if not postMessage instruction
           const instructionId = instruction.data;
-          if (instructionId[0] !== 0x08 && instructionId[0] !== 0x01) continue;
+          if (
+            instruction.programIdIndex === programIdIndex &&
+            instructionId[0] === POST_MESSAGE_UNRELIABLE_INSTRUCTION_ID
+          ) {
+            // TODO:  Do I need to verify that this message has no data?
+            // This is an unreliable wormhole message.  It is only used in conjunction with a shim message.
+            needShim = true;
+            continue;
+          }
 
-          const accountId = accountKeys[instruction.accountKeyIndexes[1]];
+          let emitterAddress: UniversalAddress;
+          let sequence: bigint;
 
-          const acctInfo = await this.getConnection().getAccountInfo(accountId, COMMITMENT);
-          if (!acctInfo?.data) throw new Error('No data found in message account');
-          const { emitterAddress, sequence } = deserializePostMessage(
-            new Uint8Array(acctInfo.data)
-          );
+          if (instruction.programIdIndex === programIdIndex) {
+            if (instructionId[0] !== POST_MESSAGE_INSTRUCTION_ID) {
+              console.log('Got non-post message instruction');
+              continue;
+            }
+            const accountId = accountKeys[instruction.accountKeyIndexes[1]];
+
+            const acctInfo = await this.getConnection().getAccountInfo(accountId, COMMITMENT);
+            if (!acctInfo?.data) throw new Error('No data found in message account');
+            const deserializedMsg = deserializePostMessage(new Uint8Array(acctInfo.data));
+            emitterAddress = deserializedMsg.emitterAddress;
+            sequence = deserializedMsg.sequence;
+          } else {
+            // instruction.programIdIndex === shimProgramIdIndex
+            console.log('Got shim instruction');
+            gotShim = true;
+            const parsedMsg = this.parseShimMessage(instruction.data);
+            if (!parsedMsg) {
+              console.log('Failed to parse shim message');
+              continue;
+            }
+            emitterAddress = parsedMsg.emitterAddress;
+            sequence = parsedMsg.sequence;
+          }
+          // TODO: should I check if needShim === gotShim?
 
           vaaKeys.push(
             makeVaaKey(
-              res.transaction.signatures[0],
+              res.transaction.signatures[0], // This is the tx hash
               this.chain,
               universalAddress_stripped(emitterAddress),
               sequence.toString()
@@ -217,6 +275,28 @@ export class SolanaWatcher extends Watcher {
     return { vaasByBlock: { [lastBlockKey]: [], ...vaasByBlock } };
   }
 
+  parseShimMessage(data: Uint8Array): {
+    emitterAddress: UniversalAddress;
+    sequence: bigint;
+  } | null {
+    // First step is to convert the data into a hex string
+    const hexData = encoding.hex.encode(data);
+
+    // Next, we need to check which discriminator is present in the data
+    if (hexData.startsWith(shimMessageEventDiscriminator)) {
+      // The data is in the format of the discriminator followed by the emitter address, sequence number, and timestamp.
+      // The emitter address is 32 bytes, the sequence number is 8 bytes, and the timestamp is 4 bytes.
+
+      // Try using the layout instead
+      const decoded = deserialize(shimMessageEventLayout, data);
+      const emitterAddress = new UniversalAddress(decoded.emitterAddress);
+      const sequence = BigInt(decoded.sequence);
+
+      return { emitterAddress, sequence };
+    }
+    return null;
+  }
+
   isValidVaaKey(key: string) {
     try {
       const [txHash, vaaKey] = key.split(':');