feat: add target-chain-height to commit-block

This allows us to check if the target block is anywhere in the past, not
just the last block. That means if the block commit misses its target
block, but lands in a different block that is still in the same fork as
the target block, then the block commit can be successful.

core-contracts/contracts/subnet.clar

@@ -27,8 +27,8 @@
 (define-constant ERR_VALIDATION_FAILED 10)
 ;;; The value supplied for `target-chain-tip` does not match the current chain tip.
 (define-constant ERR_INVALID_CHAIN_TIP 11)
-;;; The contract was called before reaching this-chain height reaches 1.
-(define-constant ERR_CALLED_TOO_EARLY 12)
+;;; The target block height is beyond the current chain tip.
+(define-constant ERR_INVALID_CHAIN_HEIGHT 12)
 (define-constant ERR_MINT_FAILED 13)
 (define-constant ERR_ATTEMPT_TO_TRANSFER_ZERO_AMOUNT 14)
 (define-constant ERR_IN_COMPUTATION 15)
@@ -127,15 +127,19 @@
 ;; Helper function: determines whether the commit-block operation satisfies pre-conditions
 ;; listed in `commit-block`.
 ;; Returns response<bool, int>
-(define-private (can-commit-block? (l1-block-height uint)  (target-chain-tip (buff 32)))
+(define-private (can-commit-block?
+        (l1-block-height uint)
+        (target-chain-tip (buff 32))
+        (target-chain-height uint)
+    )
     (begin
         ;; check no block has been committed at this height
         (asserts! (is-none (map-get? block-commits l1-block-height)) (err ERR_BLOCK_ALREADY_COMMITTED))
 
-        ;; check that `target-chain-tip` matches the burn chain tip
+        ;; check that `target-chain-tip` matches the block at the specified height
         (asserts! (is-eq
             target-chain-tip
-            (unwrap! (get-block-info? id-header-hash (- block-height u1)) (err ERR_CALLED_TOO_EARLY)) )
+            (unwrap! (get-block-info? id-header-hash target-chain-height) (err ERR_INVALID_CHAIN_HEIGHT)))
             (err ERR_INVALID_CHAIN_TIP))
 
         ;; check that the tx sender is one of the miners
@@ -183,10 +187,11 @@
         (block (buff 32))
         (subnet-block-height uint)
         (target-chain-tip (buff 32))
+        (target-chain-heght uint)
         (withdrawal-root (buff 32))
     )
     (let ((l1-block-height block-height))
-        (try! (can-commit-block? l1-block-height target-chain-tip))
+        (try! (can-commit-block? l1-block-height target-chain-tip target-chain-heght))
         (inner-commit-block block subnet-block-height l1-block-height withdrawal-root)
     )
 )

testnet/stacks-node/src/burnchains/commitment.rs

@@ -43,6 +43,7 @@ pub trait Layer1Committer {
         committed_block_hash: BlockHeaderHash,
         committed_block_height: u64,
         target_tip: BurnchainHeaderHash,
+        target_height: u64,
         withdrawal_merkle_root: Sha512Trunc256Sum,
         signatures: Vec<ClaritySignature>,
         attempt: u64,
@@ -235,6 +236,7 @@ impl MultiPartyCommitter {
         commit_to: BlockHeaderHash,
         committed_block_height: u64,
         target_tip: BurnchainHeaderHash,
+        target_height: u64,
         withdrawal_root: Sha512Trunc256Sum,
         signatures: Vec<ClaritySignature>,
     ) -> Result<StacksTransaction, Error> {
@@ -253,6 +255,7 @@ impl MultiPartyCommitter {
         let height_val = ClarityValue::UInt(committed_block_height.into());
         let target_tip_val = ClarityValue::buff_from(target_tip.as_bytes().to_vec())
             .map_err(|_| Error::BadCommitment)?;
+        let target_height_val = ClarityValue::UInt(target_height.into());
         let withdrawal_root_val = ClarityValue::buff_from(withdrawal_root.as_bytes().to_vec())
             .map_err(|_| Error::BadCommitment)?;
         let signatures_val = ClarityValue::cons_list(
@@ -272,6 +275,7 @@ impl MultiPartyCommitter {
             ("subnet-block-height".into(), height_val),
             ("withdrawal-root".into(), withdrawal_root_val),
             ("target-tip".into(), target_tip_val),
+            ("target-height".into(), target_height_val),
         ])
         .map_err(|_| Error::BadCommitment)?;
 
@@ -308,6 +312,7 @@ impl MultiPartyCommitter {
         committed_block_hash: BlockHeaderHash,
         committed_block_height: u64,
         target_tip: BurnchainHeaderHash,
+        target_height: u64,
         withdrawal_merkle_root: Sha512Trunc256Sum,
         signatures: Vec<ClaritySignature>,
         attempt: u64,
@@ -334,6 +339,7 @@ impl MultiPartyCommitter {
                 committed_block_hash,
                 committed_block_height,
                 target_tip,
+                target_height,
                 withdrawal_merkle_root,
                 signatures.clone(),
             )
@@ -357,6 +363,7 @@ impl MultiPartyCommitter {
             committed_block_hash,
             committed_block_height,
             target_tip,
+            target_height,
             withdrawal_merkle_root,
             signatures,
         )
@@ -438,6 +445,7 @@ impl Layer1Committer for MultiPartyCommitter {
         committed_block_hash: BlockHeaderHash,
         committed_block_height: u64,
         target_tip: BurnchainHeaderHash,
+        target_height: u64,
         withdrawal_merkle_root: Sha512Trunc256Sum,
         signatures: Vec<ClaritySignature>,
         attempt: u64,
@@ -447,6 +455,7 @@ impl Layer1Committer for MultiPartyCommitter {
             committed_block_hash,
             committed_block_height,
             target_tip,
+            target_height,
             withdrawal_merkle_root,
             signatures,
             attempt,
@@ -465,6 +474,7 @@ impl Layer1Committer for DirectCommitter {
         committed_block_hash: BlockHeaderHash,
         committed_block_height: u64,
         target_tip: BurnchainHeaderHash,
+        target_height: u64,
         withdrawal_merkle_root: Sha512Trunc256Sum,
         _signatures: Vec<ClaritySignature>,
         attempt: u64,
@@ -474,6 +484,7 @@ impl Layer1Committer for DirectCommitter {
             committed_block_hash,
             committed_block_height,
             target_tip,
+            target_height,
             withdrawal_merkle_root,
             attempt,
             op_signer,
@@ -498,6 +509,7 @@ impl DirectCommitter {
         commit_to: BlockHeaderHash,
         committed_block_height: u64,
         target_tip: BurnchainHeaderHash,
+        target_height: u64,
         withdrawal_root: Sha512Trunc256Sum,
     ) -> Result<StacksTransaction, Error> {
         let QualifiedContractIdentifier {
@@ -520,6 +532,7 @@ impl DirectCommitter {
                 ClarityValue::buff_from(committed_block).map_err(|_| Error::BadCommitment)?,
                 ClarityValue::UInt(committed_block_height.into()),
                 ClarityValue::buff_from(target_tip_bytes).map_err(|_| Error::BadCommitment)?,
+                ClarityValue::UInt(target_height.into()),
                 ClarityValue::buff_from(withdrawal_root_bytes).map_err(|_| Error::BadCommitment)?,
             ],
         };
@@ -550,6 +563,7 @@ impl DirectCommitter {
         committed_block_hash: BlockHeaderHash,
         committed_block_height: u64,
         target_tip: BurnchainHeaderHash,
+        target_height: u64,
         withdrawal_merkle_root: Sha512Trunc256Sum,
         attempt: u64,
         op_signer: &mut BurnchainOpSigner,
@@ -575,6 +589,7 @@ impl DirectCommitter {
                 committed_block_hash,
                 committed_block_height,
                 target_tip,
+                target_height,
                 withdrawal_merkle_root,
             )
             .map_err(|e| {
@@ -597,6 +612,7 @@ impl DirectCommitter {
             committed_block_hash,
             committed_block_height,
             target_tip,
+            target_height,
             withdrawal_merkle_root,
         )
         .map_err(|e| {

testnet/stacks-node/src/burnchains/l1_events.rs

@@ -456,6 +456,7 @@ impl BurnchainController for L1Controller {
         committed_block_hash: BlockHeaderHash,
         committed_block_height: u64,
         target_tip: BurnchainHeaderHash,
+        target_height: u64,
         withdrawal_merkle_root: Sha512Trunc256Sum,
         signatures: Vec<super::ClaritySignature>,
         op_signer: &mut BurnchainOpSigner,
@@ -467,6 +468,7 @@ impl BurnchainController for L1Controller {
             committed_block_hash,
             committed_block_height,
             target_tip,
+            target_height,
             withdrawal_merkle_root,
             signatures,
             attempt,

testnet/stacks-node/src/burnchains/mock_events.rs

@@ -420,6 +420,7 @@ impl BurnchainController for MockController {
         committed_block_hash: BlockHeaderHash,
         _committed_block_height: u64,
         _target_block: BurnchainHeaderHash,
+        _target_block_height: u64,
         withdrawal_merkle_root: Sha512Trunc256Sum,
         _signatures: Vec<ClaritySignature>,
         _op_signer: &mut BurnchainOpSigner,

testnet/stacks-node/src/burnchains/mod.rs

@@ -115,6 +115,7 @@ pub trait BurnchainController {
         committed_block_hash: BlockHeaderHash,
         committed_block_height: u64,
         target_burn_chain: BurnchainHeaderHash,
+        target_burn_block_height: u64,
         withdrawal_merkle_root: Sha512Trunc256Sum,
         signatures: Vec<ClaritySignature>,
         op_signer: &mut BurnchainOpSigner,
@@ -224,6 +225,7 @@ impl BurnchainController for PanicController {
         _committed_block_hash: BlockHeaderHash,
         _committed_block_height: u64,
         _target_block: BurnchainHeaderHash,
+        _target_block_height: u64,
         _withdrawal_merkle_root: Sha512Trunc256Sum,
         _signatures: Vec<ClaritySignature>,
         _op_signer: &mut BurnchainOpSigner,

testnet/stacks-node/src/neon_node.rs

@@ -1898,6 +1898,7 @@ impl StacksNode {
         // collect required contents for commit
         let committed_block_hash = anchored_block.block_hash();
         let target_burn_hash = burn_block.burn_header_hash.clone();
+        let target_burn_height = burn_block.block_height;
         let withdrawal_merkle_root = anchored_block.header.withdrawal_merkle_root;
 
         let mut op_signer = keychain.generate_op_signer();
@@ -2005,6 +2006,7 @@ impl StacksNode {
             committed_block_hash,
             block_height,
             target_burn_hash,
+            target_burn_height,
             withdrawal_merkle_root,
             signatures,
             &mut op_signer,