Sealevel v3 contracts (#3048)

### Description

MVP contracts for sealevel v3 - note this doesn't include hooks so IGP
payments still have to be made separately. However contracts will now be
compatible with the metadata format used by the other V3 deployments.

### Drive-by changes

The unit tests in
`rust/sealevel/programs/ism/multisig-ism-message-id/src/metadata.rs` are
refactored to reuse struct creation logic.

### Related issues

- Fixes https://github.com/hyperlane-xyz/hyperlane-monorepo/issues/3044
- Fixes https://github.com/hyperlane-xyz/hyperlane-monorepo/issues/3045

### Backward compatibility

No, since this upgrades sealevel v2 to v3.

### Testing

Unit tests

rust/Cargo.lock

@@ -4400,6 +4400,7 @@ dependencies = [
  "multisig-ism",
  "num-derive 0.4.1",
  "num-traits",
+ "rand 0.8.5",
  "serializable-account-meta",
  "solana-program",
  "solana-program-test",

rust/sealevel/libraries/multisig-ism/src/test_data.rs

@@ -17,7 +17,7 @@ const DESTINATION_DOMAIN: u32 = 4321u32;
 
 pub fn get_multisig_ism_test_data() -> MultisigIsmTestData {
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 69,
         origin: ORIGIN_DOMAIN,
         sender: H256::from_str(
@@ -49,31 +49,31 @@ pub fn get_multisig_ism_test_data() -> MultisigIsmTestData {
     };
 
     // checkpoint.signing_hash() is equal to:
-    // 0x4fc33ff33d5e9305a2d87f7824d1b943ba219cff4c153ae8fd39b0d8620fc332
+    // 0x5c2b4cbafdd7319d9a3dea4aa078748ae53368e1521494a80cf4259b9c6dba6a
 
     // Validator 0:
     // Address: 0xE3DCDBbc248cE191bDc271f3FCcd0d95911BFC5D
     // Private Key: 0x788aa7213bd92ff92017d767fde0d75601425818c8e4b21e87314c2a4dcd6091
     let validator_0 = H160::from_str("0xE3DCDBbc248cE191bDc271f3FCcd0d95911BFC5D").unwrap();
-    // > await (new ethers.Wallet('0x788aa7213bd92ff92017d767fde0d75601425818c8e4b21e87314c2a4dcd6091')).signMessage(ethers.utils.arrayify('0x4fc33ff33d5e9305a2d87f7824d1b943ba219cff4c153ae8fd39b0d8620fc332'))
-    // '0x3a06cc01fef07025ee5ae9e29ae783338fe11f5c21af383fb8cc5878a2ea3616125c230ec07b059eaebb842af0a51040ad3214f9050cccef36b5c21c9c9cc4ba1b'
-    let signature_0 = hex::decode("3a06cc01fef07025ee5ae9e29ae783338fe11f5c21af383fb8cc5878a2ea3616125c230ec07b059eaebb842af0a51040ad3214f9050cccef36b5c21c9c9cc4ba1b").unwrap();
+    // > await (new ethers.Wallet('0x788aa7213bd92ff92017d767fde0d75601425818c8e4b21e87314c2a4dcd6091')).signMessage(ethers.utils.arrayify('0x5c2b4cbafdd7319d9a3dea4aa078748ae53368e1521494a80cf4259b9c6dba6a'))
+    // '0xb8875fb75adf471e43a943b78eb422ffe86a4291fa6324f9f875241605ca831d2b4225358936deee7501cf305aafc1677e3dc9bcfea4caec54f4cde49d416bd91b'
+    let signature_0 = hex::decode("b8875fb75adf471e43a943b78eb422ffe86a4291fa6324f9f875241605ca831d2b4225358936deee7501cf305aafc1677e3dc9bcfea4caec54f4cde49d416bd91b").unwrap();
 
     // Validator 1:
     // Address: 0xb25206874C24733F05CC0dD11924724A8E7175bd
     // Private Key: 0x4a599de3915f404d84a2ebe522bfe7032ebb1ca76a65b55d6eb212b129043a0e
     let validator_1 = H160::from_str("0xb25206874C24733F05CC0dD11924724A8E7175bd").unwrap();
-    // > await (new ethers.Wallet('0x4a599de3915f404d84a2ebe522bfe7032ebb1ca76a65b55d6eb212b129043a0e')).signMessage(ethers.utils.arrayify('0x4fc33ff33d5e9305a2d87f7824d1b943ba219cff4c153ae8fd39b0d8620fc332'))
-    // '0xfd34aac152ec85a79211c990f308c7e719145e2e67e48f2d10db4347d3a9102131254eccbcd0fe389afad96b88d368192b33649336893dfe1bbad43901d1bef71b'
-    let signature_1 = hex::decode("fd34aac152ec85a79211c990f308c7e719145e2e67e48f2d10db4347d3a9102131254eccbcd0fe389afad96b88d368192b33649336893dfe1bbad43901d1bef71b").unwrap();
+    // > await (new ethers.Wallet('0x4a599de3915f404d84a2ebe522bfe7032ebb1ca76a65b55d6eb212b129043a0e')).signMessage(ethers.utils.arrayify('0x5c2b4cbafdd7319d9a3dea4aa078748ae53368e1521494a80cf4259b9c6dba6a'))
+    // '0xfa8d61da2e0ac6f32c8432e75770d90483613efe96b442fbca9ca8d200447bf979f46529c7341879333a9c24a7d3fba08b53d13447618b71cf2ee4734e82f96e1c'
+    let signature_1 = hex::decode("fa8d61da2e0ac6f32c8432e75770d90483613efe96b442fbca9ca8d200447bf979f46529c7341879333a9c24a7d3fba08b53d13447618b71cf2ee4734e82f96e1c").unwrap();
 
     // Validator 2:
     // Address: 0x28b8d0E2bBfeDe9071F8Ff3DaC9CcE3d3176DBd3
     // Private Key: 0x2cc76d56db9924ddc3388164454dfea9edd2d5f5da81102fd3594fc7c5281515
     let validator_2 = H160::from_str("0x28b8d0E2bBfeDe9071F8Ff3DaC9CcE3d3176DBd3").unwrap();
-    // > await (new ethers.Wallet('0x2cc76d56db9924ddc3388164454dfea9edd2d5f5da81102fd3594fc7c5281515')).signMessage(ethers.utils.arrayify('0x4fc33ff33d5e9305a2d87f7824d1b943ba219cff4c153ae8fd39b0d8620fc332'))
-    // '0x85992e471002c40730d2b91831ba40cd8ffcebf4905646c25b7b6abb7575f25d19395045466e833b7700e233bfa5836f0a459da05bf817efd6cb4f55bcaec4b51c'
-    let signature_2 = hex::decode("85992e471002c40730d2b91831ba40cd8ffcebf4905646c25b7b6abb7575f25d19395045466e833b7700e233bfa5836f0a459da05bf817efd6cb4f55bcaec4b51c").unwrap();
+    // > await (new ethers.Wallet('0x2cc76d56db9924ddc3388164454dfea9edd2d5f5da81102fd3594fc7c5281515')).signMessage(ethers.utils.arrayify('0x5c2b4cbafdd7319d9a3dea4aa078748ae53368e1521494a80cf4259b9c6dba6a'))
+    // '0x6c60c3744f6bf779017b8ab9aa8eed60bf53c317cf4d74d765015cc0a7dcad783dee39334bfc7e4baab944355914e7431e4286df8c0557a0c1f6ba867677da421b'
+    let signature_2 = hex::decode("6c60c3744f6bf779017b8ab9aa8eed60bf53c317cf4d74d765015cc0a7dcad783dee39334bfc7e4baab944355914e7431e4286df8c0557a0c1f6ba867677da421b").unwrap();
 
     MultisigIsmTestData {
         message,

rust/sealevel/programs/hyperlane-sealevel-token-collateral/tests/functional.rs

@@ -725,7 +725,7 @@ async fn test_transfer_remote(spl_token_program_id: Pubkey) {
         .unwrap();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: LOCAL_DOMAIN,
         sender: program_id.to_bytes().into(),
@@ -869,7 +869,7 @@ async fn transfer_from_remote(
         );
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: origin_override.unwrap_or(REMOTE_DOMAIN),
         // Default to the remote router as the sender

rust/sealevel/programs/hyperlane-sealevel-token-native/tests/functional.rs

@@ -510,7 +510,7 @@ async fn test_transfer_remote() {
         .unwrap();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: LOCAL_DOMAIN,
         sender: program_id.to_bytes().into(),
@@ -616,7 +616,7 @@ async fn transfer_from_remote(
     let recipient: H256 = recipient_pubkey.to_bytes().into();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: origin_override.unwrap_or(REMOTE_DOMAIN),
         // Default to the remote router as the sender

rust/sealevel/programs/hyperlane-sealevel-token/tests/functional.rs

@@ -451,7 +451,7 @@ async fn transfer_from_remote(
         );
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: origin_override.unwrap_or(REMOTE_DOMAIN),
         // Default to the remote router as the sender
@@ -783,7 +783,7 @@ async fn test_transfer_remote() {
         .unwrap();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: LOCAL_DOMAIN,
         sender: program_id.to_bytes().into(),

rust/sealevel/programs/ism/multisig-ism-message-id/Cargo.toml

@@ -27,10 +27,13 @@ serializable-account-meta = { path = "../../../libraries/serializable-account-me
 [dev-dependencies]
 hyperlane-sealevel-multisig-ism-message-id = { path = "../multisig-ism-message-id" }
 hyperlane-test-utils = { path = "../../../libraries/test-utils" }
+multisig-ism = { path = "../../../libraries/multisig-ism", features = ["test-data"] }
 solana-program-test.workspace = true
 solana-sdk.workspace = true
 hex.workspace = true
-multisig-ism = { path = "../../../libraries/multisig-ism", features = ["test-data"] }
+# Can't have as a workspace dep, because this is already in the dep tree twice: once as
+# an older solana one, once as a newer one used more generally.
+rand = "0.8.5"
 
 [lib]
 crate-type = ["cdylib", "lib"]

rust/sealevel/programs/ism/multisig-ism-message-id/src/metadata.rs

@@ -7,12 +7,14 @@ use crate::error::Error;
 pub struct MultisigIsmMessageIdMetadata {
     pub origin_merkle_tree_hook: H256,
     pub merkle_root: H256,
+    pub merkle_index: u32,
     pub validator_signatures: Vec<EcdsaSignature>,
 }
 
 const ORIGIN_MAILBOX_OFFSET: usize = 0;
 const MERKLE_ROOT_OFFSET: usize = 32;
-const SIGNATURES_OFFSET: usize = 64;
+const MERKLE_INDEX_OFFSET: usize = 64;
+const SIGNATURES_OFFSET: usize = 68;
 const SIGNATURE_LENGTH: usize = 65;
 
 /// Format of metadata:
@@ -32,7 +34,12 @@ impl TryFrom<Vec<u8>> for MultisigIsmMessageIdMetadata {
         }
 
         let origin_mailbox = H256::from_slice(&bytes[ORIGIN_MAILBOX_OFFSET..MERKLE_ROOT_OFFSET]);
-        let merkle_root = H256::from_slice(&bytes[MERKLE_ROOT_OFFSET..SIGNATURES_OFFSET]);
+        let merkle_root = H256::from_slice(&bytes[MERKLE_ROOT_OFFSET..MERKLE_INDEX_OFFSET]);
+        // This cannot panic since SIGNATURES_OFFSET - MERKLE_INDEX_OFFSET is 4.
+        let merkle_index_bytes: [u8; 4] = bytes[MERKLE_INDEX_OFFSET..SIGNATURES_OFFSET]
+            .try_into()
+            .map_err(|_| Error::InvalidMetadata)?;
+        let merkle_index = u32::from_be_bytes(merkle_index_bytes);
 
         let signature_bytes_len = bytes_len - SIGNATURES_OFFSET;
         // Require the signature bytes to be a multiple of the signature length.
@@ -55,6 +62,7 @@ impl TryFrom<Vec<u8>> for MultisigIsmMessageIdMetadata {
         Ok(Self {
             origin_merkle_tree_hook: origin_mailbox,
             merkle_root,
+            merkle_index,
             validator_signatures,
         })
     }
@@ -68,6 +76,7 @@ impl Encode for MultisigIsmMessageIdMetadata {
         let mut bytes_written = 0;
         bytes_written += writer.write(self.origin_merkle_tree_hook.as_ref())?;
         bytes_written += writer.write(self.merkle_root.as_ref())?;
+        bytes_written += writer.write(&self.merkle_index.to_be_bytes())?;
         for signature in &self.validator_signatures {
             bytes_written += writer.write(&signature.as_fixed_bytes()[..])?;
         }
@@ -78,11 +87,21 @@ impl Encode for MultisigIsmMessageIdMetadata {
 #[cfg(test)]
 mod test {
     use super::*;
+    use rand::Rng;
+
+    // Provide a default test implementation
+    fn dummy_metadata_with_sigs(sigs: Vec<EcdsaSignature>) -> MultisigIsmMessageIdMetadata {
+        let mut rng = rand::thread_rng();
+        MultisigIsmMessageIdMetadata {
+            origin_merkle_tree_hook: H256::random(),
+            merkle_root: H256::random(),
+            merkle_index: rng.gen(),
+            validator_signatures: sigs,
+        }
+    }
 
     #[test]
     fn test_decode_correctly_formatted_metadata() {
-        let origin_mailbox = H256::random();
-        let merkle_root = H256::random();
         let validator_signatures = vec![
             EcdsaSignature {
                 serialized_rs: [11u8; 64],
@@ -97,43 +116,49 @@ mod test {
                 recovery_id: 0,
             },
         ];
-        let mut metadata_bytes = origin_mailbox.as_bytes().to_vec();
-        metadata_bytes.extend_from_slice(merkle_root.as_bytes());
-        for signature in &validator_signatures {
-            metadata_bytes.extend_from_slice(&signature.as_fixed_bytes()[..]);
-        }
-
-        let metadata = MultisigIsmMessageIdMetadata::try_from(metadata_bytes).unwrap();
-        assert_eq!(metadata.origin_merkle_tree_hook, origin_mailbox);
-        assert_eq!(metadata.merkle_root, merkle_root);
-        assert_eq!(metadata.validator_signatures, validator_signatures);
+        let test_meta = dummy_metadata_with_sigs(validator_signatures);
+        let encoded_meta = test_meta.to_vec();
+        let metadata = MultisigIsmMessageIdMetadata::try_from(encoded_meta.clone()).unwrap();
+        assert_eq!(
+            metadata.origin_merkle_tree_hook,
+            test_meta.origin_merkle_tree_hook
+        );
+        assert_eq!(metadata.merkle_root, test_meta.merkle_root);
+        assert_eq!(metadata.merkle_index, test_meta.merkle_index);
+        assert_eq!(
+            metadata.validator_signatures,
+            test_meta.validator_signatures
+        );
     }
 
     #[test]
     fn test_decode_no_signatures_is_err() {
-        let origin_mailbox = H256::random();
-        let merkle_root = H256::random();
-        let metadata_bytes = origin_mailbox
-            .as_bytes()
-            .iter()
-            .chain(merkle_root.as_bytes().iter())
-            .cloned()
-            .collect::<Vec<u8>>();
-
-        let result = MultisigIsmMessageIdMetadata::try_from(metadata_bytes);
+        let test_meta = dummy_metadata_with_sigs(vec![]);
+        let encoded_meta = test_meta.to_vec();
+        let result = MultisigIsmMessageIdMetadata::try_from(encoded_meta);
         assert!(result.unwrap_err() == Error::InvalidMetadata);
     }
 
     #[test]
     fn test_decode_incorrect_signature_length_is_err() {
-        let origin_mailbox = H256::random();
-        let merkle_root = H256::random();
-        let mut metadata_bytes = origin_mailbox.as_bytes().to_vec();
-        metadata_bytes.extend_from_slice(merkle_root.as_bytes());
-        // 64 byte signature instead of 65.
-        metadata_bytes.extend_from_slice(&[1u8; 64]);
-
-        let result = MultisigIsmMessageIdMetadata::try_from(metadata_bytes);
+        let sigs = vec![EcdsaSignature {
+            serialized_rs: [1u8; 64],
+            recovery_id: 0,
+        }];
+        let test_meta = dummy_metadata_with_sigs(sigs);
+        let encoded_meta = test_meta.to_vec();
+        // remove the last byte from the encoded signature
+        let faulty_encoded_meta = encoded_meta[..encoded_meta.len() - 1].to_vec();
+        let result = MultisigIsmMessageIdMetadata::try_from(faulty_encoded_meta);
         assert!(result.unwrap_err() == Error::InvalidMetadata);
+        MultisigIsmMessageIdMetadata::try_from(encoded_meta).expect("Decoding should succeed");
+    }
+
+    #[test]
+    fn test_decode_real_meta() {
+        // multisig ism message id metadata from this tx:
+        // https://arbiscan.io//tx/0xe558f04ad446b1d9ec4d4a1284661869b73daff38ec9fb7e809be652732fff30#txninfo
+        let bytes = hex::decode("000000000000000000000000149db7afd694722747035d5aec7007ccb6f8f112fb91807ccda2db543bfbd013242643553bc1238f891ae9d0abb3b8b46c5a89990000017addc429c97ca8bcd6ad86ef4461379374b0d545308a1f47db246a6c028f74d7af521dd9355afd2f2a02565a24f22ac7b7e388cbd1f2a931acc97ce689be5456851b4d22f1aece05d293e574e38edcda9f2db64f1dc5b69a89a6a5989e7aaa4f443c137e593bb794eb211de719ed0f466a0778c4d204cc275f54c0936eee918ae1651c").unwrap();
+        MultisigIsmMessageIdMetadata::try_from(bytes).expect("Decoding should succeed");
     }
 }

rust/sealevel/programs/ism/multisig-ism-message-id/src/processor.rs

@@ -601,6 +601,7 @@ pub mod test {
                 metadata: MultisigIsmMessageIdMetadata {
                     origin_merkle_tree_hook: checkpoint.merkle_tree_hook_address,
                     merkle_root: checkpoint.root,
+                    merkle_index: checkpoint.index,
                     validator_signatures: vec![
                         EcdsaSignature::from_bytes(&signatures[0]).unwrap(),
                         EcdsaSignature::from_bytes(&signatures[1]).unwrap(),
@@ -626,6 +627,7 @@ pub mod test {
                 metadata: MultisigIsmMessageIdMetadata {
                     origin_merkle_tree_hook: checkpoint.merkle_tree_hook_address,
                     merkle_root: checkpoint.root,
+                    merkle_index: checkpoint.index,
                     validator_signatures: vec![
                         EcdsaSignature::from_bytes(&signatures[1]).unwrap(),
                         EcdsaSignature::from_bytes(&signatures[0]).unwrap(),
@@ -654,6 +656,7 @@ pub mod test {
                 metadata: MultisigIsmMessageIdMetadata {
                     origin_merkle_tree_hook: checkpoint.merkle_tree_hook_address,
                     merkle_root: checkpoint.root,
+                    merkle_index: checkpoint.index,
                     validator_signatures: vec![
                         EcdsaSignature::from_bytes(&signatures[0]).unwrap(),
                         EcdsaSignature::from_bytes(&signatures[2]).unwrap(),
@@ -678,6 +681,7 @@ pub mod test {
                 metadata: MultisigIsmMessageIdMetadata {
                     origin_merkle_tree_hook: checkpoint.merkle_tree_hook_address,
                     merkle_root: checkpoint.root,
+                    merkle_index: checkpoint.index,
                     validator_signatures: vec![
                         EcdsaSignature::from_bytes(&signatures[0]).unwrap(),
                         EcdsaSignature::from_bytes(&signatures[1]).unwrap(),

rust/sealevel/programs/ism/multisig-ism-message-id/tests/functional.rs

@@ -299,7 +299,7 @@ async fn test_set_validators_and_threshold_creates_pda_account() {
     // to fetch the account metas required for the instruction.
 
     let test_message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: domain,
         sender: H256::random(),
@@ -421,6 +421,7 @@ async fn test_ism_verify() {
         metadata: MultisigIsmMessageIdMetadata {
             origin_merkle_tree_hook: checkpoint.merkle_tree_hook_address,
             merkle_root: checkpoint.root,
+            merkle_index: checkpoint.index,
             validator_signatures: vec![
                 EcdsaSignature::from_bytes(&signatures[0]).unwrap(),
                 EcdsaSignature::from_bytes(&signatures[1]).unwrap(),

rust/sealevel/programs/mailbox-test/src/functional.rs

@@ -183,7 +183,7 @@ async fn test_dispatch_from_eoa() {
         .unwrap();
 
     let expected_message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: LOCAL_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -238,7 +238,7 @@ async fn test_dispatch_from_eoa() {
         .unwrap();
 
     let expected_message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 1,
         origin: LOCAL_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -300,7 +300,7 @@ async fn test_dispatch_from_program() {
             .unwrap();
 
     let expected_message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: LOCAL_DOMAIN,
         // The sender should be the program ID because its dispatch authority signed
@@ -389,7 +389,7 @@ async fn test_dispatch_returns_message_id() {
         message_body: message_body.clone(),
     };
     let expected_message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: LOCAL_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -574,7 +574,7 @@ async fn test_process_successful_verify_and_handle() {
     let recipient_id = hyperlane_sealevel_test_send_receiver::id();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: REMOTE_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -605,7 +605,7 @@ async fn test_process_successful_verify_and_handle() {
 
     // Send another to illustrate that the sequence is incremented
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: REMOTE_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -647,7 +647,7 @@ async fn test_process_errors_if_message_already_processed() {
     let recipient_id = hyperlane_sealevel_test_send_receiver::id();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: REMOTE_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -697,7 +697,7 @@ async fn test_process_errors_if_ism_verify_fails() {
     test_ism.set_accept(false).await.unwrap();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: REMOTE_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -743,7 +743,7 @@ async fn test_process_errors_if_recipient_handle_fails() {
         .unwrap();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: REMOTE_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -784,7 +784,7 @@ async fn test_process_errors_if_incorrect_destination_domain() {
     let recipient_id = hyperlane_sealevel_test_send_receiver::id();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: REMOTE_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),
@@ -905,7 +905,7 @@ async fn test_process_errors_if_reentrant() {
     let recipient_id = hyperlane_sealevel_test_send_receiver::id();
 
     let message = HyperlaneMessage {
-        version: 0,
+        version: 3,
         nonce: 0,
         origin: REMOTE_DOMAIN,
         sender: payer.pubkey().to_bytes().into(),

rust/sealevel/programs/mailbox/src/instruction.rs

@@ -11,7 +11,7 @@ use solana_program::{
 use crate::{mailbox_inbox_pda_seeds, mailbox_outbox_pda_seeds};
 
 /// The current message version.
-pub const VERSION: u8 = 0;
+pub const VERSION: u8 = 3;
 
 /// Maximum bytes per message = 2 KiB (somewhat arbitrarily set to begin).
 pub const MAX_MESSAGE_BODY_BYTES: usize = 2 * 2_usize.pow(10);