solana: update inbox item PDA derivation

the chain id and message are now hashed together

Author: kcsongor

solana/programs/example-native-token-transfers/src/instructions/redeem.rs

@@ -56,8 +56,9 @@ pub struct Redeem<'info> {
         space = 8 + InboxItem::INIT_SPACE,
         seeds = [
             InboxItem::SEED_PREFIX,
-            endpoint_message.from_chain.id.to_be_bytes().as_ref(),
-            endpoint_message.message.manager_payload.keccak256().as_ref(),
+            endpoint_message.message.manager_payload.keccak256(
+                endpoint_message.from_chain
+            ).as_ref(),
         ],
         bump,
     )]

solana/programs/example-native-token-transfers/src/messages.rs

@@ -17,9 +17,11 @@ pub struct ManagerMessage<A: Space> {
 }
 
 impl<A: Space + AnchorSerialize + fmt::Debug + TypePrefixedPayload> ManagerMessage<A> {
-    pub fn keccak256(&self) -> Hash {
-        let payload = TypePrefixedPayload::to_vec_payload(self);
-        solana_program::keccak::hash(&payload)
+    pub fn keccak256(&self, chain_id: ChainId) -> Hash {
+        let mut bytes: Vec<u8> = Vec::new();
+        bytes.extend_from_slice(&chain_id.id.to_be_bytes());
+        bytes.extend_from_slice(&TypePrefixedPayload::to_vec_payload(self));
+        solana_program::keccak::hash(&bytes)
     }
 }
 

solana/programs/example-native-token-transfers/tests/sdk/accounts.rs

@@ -101,12 +101,12 @@ impl NTT {
         manager_message: ManagerMessage<NativeTokenTransfer>,
     ) -> Pubkey {
         let mut hasher = Keccak256::new();
+        hasher.update(&chain.to_be_bytes());
         hasher.update(&TypePrefixedPayload::to_vec_payload(&manager_message));
 
         let (inbox_item, _) = Pubkey::find_program_address(
             &[
                 InboxItem::SEED_PREFIX,
-                &chain.to_be_bytes(),
                 &hasher.finalize(),
             ],
             &self.program,

solana/ts/sdk/index.ts

@@ -94,12 +94,12 @@ export class NTT {
     const chainId = coalesceChainId(chain)
     const serialized = ManagerMessage.serialize(managerMessage, NativeTokenTransfer.serialize)
     const hasher = new Keccak(256)
+    hasher.update(new BN(chainId).toBuffer('be', 2))
     hasher.update(serialized)
     const hash = hasher.digest('hex')
     return this.derive_pda(
       [
         Buffer.from('inbox_item'),
-        new BN(chainId).toBuffer('be', 2),
         Buffer.from(hash, 'hex')
       ])
   }