Merge pull request #906 from EYBlockchain/RogerTaule/variable-length-…

…merkle-tree-transactions

Variable height merkle trees for transactions

config/default.js

@@ -28,7 +28,6 @@ module.exports = {
   EXCLUDE_DIRS: 'common',
   MAX_QUEUE: 5,
   TIMBER_HEIGHT: 32,
-  TXHASH_TREE_HEIGHT: 5,
   CONFIRMATION_POLL_TIME: 1000,
   CONFIRMATIONS: 12,
   DEFAULT_ACCOUNT_NUM: 10,
@@ -84,7 +83,7 @@ module.exports = {
   CURVE: process.env.CURVE || 'bn128',
 
   TRANSACTIONS_PER_BLOCK: Number(process.env.TRANSACTIONS_PER_BLOCK) || 2,
-  RETRIES: Number(process.env.AUTOSTART_RETRIES) || 50,
+  RETRIES: Number(process.env.AUTOSTART_RETRIES) || 150,
   USE_STUBS: process.env.USE_STUBS === 'true',
   VK_IDS: { deposit: 0, transfer: 1, withdraw: 2 }, // used as an enum to mirror the Shield contracts enum for vk types. The keys of this object must correspond to a 'folderpath' (the .zok file without the '.zok' bit)
   BN128_GROUP_ORDER: 21888242871839275222246405745257275088548364400416034343698204186575808495617n,

nightfall-client/src/event-handlers/block-proposed.mjs

@@ -24,7 +24,7 @@ import {
 } from '../services/database.mjs';
 import { decryptCommitment } from '../services/commitment-sync.mjs';
 
-const { TIMBER_HEIGHT, TXHASH_TREE_HEIGHT, HASH_TYPE, TXHASH_TREE_HASH_TYPE } = config;
+const { TIMBER_HEIGHT, HASH_TYPE, TXHASH_TREE_HASH_TYPE } = config;
 const { ZERO } = constants;
 
 /**
@@ -148,36 +148,37 @@ async function blockProposedEventHandler(data, syncing) {
     }),
   );
 
+  let height = 1;
+  while (2 ** height < block.transactionHashes.length) {
+    ++height;
+  }
+
   // If this L2 block contains withdraw transactions known to this client,
   // the following needs to be saved for later to be used during finalise/instant withdraw
   // 1. Save sibling path for the withdraw transaction hash that is present in transaction hashes timber tree
   // 2. Save transactions hash of the transactions in this L2 block that contains withdraw transactions for this client
   // transactions hash is a linear hash of the transactions in an L2 block which is calculated during proposeBlock in
   // the contract
   if ((await countWithdrawTransactionHashes(block.transactionHashes)) > 0) {
-    const transactionHashesTimber = new Timber(
-      ...[, , , ,],
-      TXHASH_TREE_HASH_TYPE,
-      TXHASH_TREE_HEIGHT,
-    );
-    const updatedTransctionHashesTimber = Timber.statelessUpdate(
+    const transactionHashesTimber = new Timber(...[, , , ,], TXHASH_TREE_HASH_TYPE, height);
+    const updatedTransactionHashesTimber = Timber.statelessUpdate(
       transactionHashesTimber,
       block.transactionHashes,
       TXHASH_TREE_HASH_TYPE,
-      TXHASH_TREE_HEIGHT,
+      height,
     );
 
     await Promise.all(
       // eslint-disable-next-line consistent-return
       block.transactionHashes.map(async (transactionHash, i) => {
         if (await isTransactionHashWithdraw(transactionHash)) {
           const siblingPathTransactionHash =
-            updatedTransctionHashesTimber.getSiblingPath(transactionHash);
+            updatedTransactionHashesTimber.getSiblingPath(transactionHash);
           return setTransactionHashSiblingInfo(
             transactionHash,
             siblingPathTransactionHash,
             transactionHashesTimber.leafCount + i,
-            updatedTransctionHashesTimber.root,
+            updatedTransactionHashesTimber.root,
           );
         }
       }),

nightfall-deployer/contracts/Config.sol

@@ -11,7 +11,7 @@ contract Config is Ownable, Structures {
     uint256 constant ROTATE_PROPOSER_BLOCKS = 4;
     uint256 constant COOLING_OFF_PERIOD = 1 weeks;
     bytes32 constant ZERO = bytes32(0);
-    uint256 constant TXHASH_TREE_HEIGHT = 5;
+    uint256 constant TRANSACTIONS_PER_BLOCK = 32;
 
     address bootProposer;
     address bootChallenger;

nightfall-deployer/contracts/Shield.sol

@@ -116,7 +116,7 @@ contract Shield is Stateful, Config, Key_Registry, ReentrancyGuardUpgradeable, P
         Block calldata b,
         Transaction calldata t,
         uint256 index,
-        bytes32[6] calldata siblingPath
+        bytes32[] calldata siblingPath
     ) external view returns (bool) {
         // check this block is a real one, in the queue, not something made up.
         state.areBlockAndTransactionReal(b, t, index, siblingPath);
@@ -149,7 +149,7 @@ contract Shield is Stateful, Config, Key_Registry, ReentrancyGuardUpgradeable, P
         Block calldata b,
         Transaction calldata t,
         uint256 index,
-        bytes32[6] calldata siblingPath
+        bytes32[] calldata siblingPath
     ) external {
         // check this block is a real one, in the queue, not something made up and that the transaction exists in the block
         state.areBlockAndTransactionReal(b, t, index, siblingPath);
@@ -224,7 +224,7 @@ contract Shield is Stateful, Config, Key_Registry, ReentrancyGuardUpgradeable, P
         Block calldata b,
         Transaction calldata t,
         uint256 index,
-        bytes32[6] calldata siblingPath
+        bytes32[] calldata siblingPath
     ) external payable nonReentrant {
         // The transaction is a withdrawal transaction
         require(t.transactionType == TransactionTypes.WITHDRAW, 'Can only advance withdrawals');

nightfall-deployer/contracts/State.sol

@@ -93,7 +93,7 @@ contract State is Initializable, ReentrancyGuardUpgradeable, Pausable, Config {
         require(BLOCK_STAKE <= msg.value, 'The stake payment is incorrect');
         require(b.proposer == msg.sender, 'The proposer address is not the sender');
         // set the maximum tx/block to prevent unchallengably large blocks
-        require(t.length < 33, 'The block has too many transactions');
+        require(t.length <= TRANSACTIONS_PER_BLOCK, 'The block has too many transactions');
 
         uint256 feePaymentsEth = 0;
         uint256 feePaymentsMatic = 0;
@@ -126,8 +126,17 @@ contract State is Initializable, ReentrancyGuardUpgradeable, Pausable, Config {
             }
             let transactionHashesRoot
             // calculate and store transaction hashes root
+            let height := 1
             for {
-                let i := 5
+
+            } lt(exp(2, height), t.length) {
+
+            } {
+                height := add(height, 1)
+            }
+
+            for {
+                let i := height
             } gt(i, 0) {
                 i := sub(i, 1)
             } {
@@ -328,7 +337,7 @@ contract State is Initializable, ReentrancyGuardUpgradeable, Pausable, Config {
         Block calldata b,
         Transaction calldata t,
         uint256 index,
-        bytes32[6] calldata siblingPath
+        bytes32[] calldata siblingPath
     ) public view {
         bytes32 blockHash = Utils.hashBlock(b);
         require(blockHashes[b.blockNumberL2].blockHash == blockHash, 'This block does not exist');

nightfall-deployer/contracts/Utils.sol

@@ -153,8 +153,16 @@ library Utils {
             } {
                 mstore(add(transactionHashesPos, mul(0x20, i)), mload(add(leavesPos, mul(0x20, i))))
             }
+            let height := 1
             for {
-                let i := 5
+
+            } lt(exp(2, height), length) {
+
+            } {
+                height := add(height, 1)
+            }
+            for {
+                let i := height
             } gt(i, 0) {
                 i := sub(i, 1)
             } {
@@ -178,11 +186,11 @@ library Utils {
     }
 
     function checkPath(
-        bytes32[6] calldata siblingPath,
+        bytes32[] calldata siblingPath,
         uint256 leafIndex,
         bytes32 node
     ) public pure returns (bool) {
-        for (uint256 i = 5; i > 0; i--) {
+        for (uint256 i = siblingPath.length - 1; i > 0; i--) {
             if (leafIndex % 2 == 0) {
                 node = keccak256(abi.encodePacked(node, siblingPath[i]));
             } else {

nightfall-optimist/src/classes/block.mjs

@@ -7,7 +7,7 @@ import constants from 'common-files/constants/index.mjs';
 import { getLatestBlockInfo, getTreeByBlockNumberL2 } from '../services/database.mjs';
 import { buildBlockSolidityStruct, calcBlockHash } from '../services/block-utils.mjs';
 
-const { TIMBER_HEIGHT, TXHASH_TREE_HEIGHT, HASH_TYPE, TXHASH_TREE_HASH_TYPE } = config;
+const { TIMBER_HEIGHT, HASH_TYPE, TXHASH_TREE_HASH_TYPE } = config;
 const { ZERO } = constants;
 
 /**
@@ -162,12 +162,17 @@ class Block {
 
   static calcTransactionHashesRoot(transactions) {
     const transactionHashes = transactions.map(t => t.transactionHash);
-    const timber = new Timber(...[, , , ,], TXHASH_TREE_HASH_TYPE, TXHASH_TREE_HEIGHT);
+    let height = 1;
+    while (2 ** height < transactionHashes.length) {
+      ++height;
+    }
+
+    const timber = new Timber(...[, , , ,], TXHASH_TREE_HASH_TYPE, height);
     const updatedTimber = Timber.statelessUpdate(
       timber,
       transactionHashes,
       TXHASH_TREE_HASH_TYPE,
-      TXHASH_TREE_HEIGHT,
+      height,
     );
     return updatedTimber.root;
   }

wallet/src/nightfall-browser/event-handlers/block-proposed.js

@@ -26,7 +26,7 @@ import {
 } from '../services/database';
 import { edwardsDecompress } from '../../common-files/utils/curve-maths/curves';
 
-const { TIMBER_HEIGHT, TXHASH_TREE_HEIGHT, HASH_TYPE, TXHASH_TREE_HASH_TYPE } = global.config;
+const { TIMBER_HEIGHT, HASH_TYPE, TXHASH_TREE_HASH_TYPE } = global.config;
 const { ZERO } = global.nightfallConstants;
 
 /**
@@ -154,37 +154,38 @@ async function blockProposedEventHandler(data, zkpPrivateKeys, nullifierKeys) {
     }),
   );
 
+  let height = 1;
+  while (2 ** height < block.transactionHashes.length) {
+    ++height;
+  }
+
   // If this L2 block contains withdraw transactions known to this client,
   // the following needs to be saved for later to be used during finalise/instant withdraw
   // 1. Save sibling path for the withdraw transaction hash that is present in transaction hashes timber tree
   // 2. Save transactions hash of the transactions in this L2 block that contains withdraw transactions for this client
   // transactions hash is a linear hash of the transactions in an L2 block which is calculated during proposeBlock in
   // the contract
   if ((await countWithdrawTransactionHashes(block.transactionHashes)) > 0) {
-    const transactionHashesTimber = new Timber(
-      ...[, , , ,],
-      TXHASH_TREE_HASH_TYPE,
-      TXHASH_TREE_HEIGHT,
-    );
+    const transactionHashesTimber = new Timber(...[, , , ,], TXHASH_TREE_HASH_TYPE, height);
 
-    const updatedTransctionHashesTimber = Timber.statelessUpdate(
+    const updatedTransactionHashesTimber = Timber.statelessUpdate(
       transactionHashesTimber,
       block.transactionHashes,
       TXHASH_TREE_HASH_TYPE,
-      TXHASH_TREE_HEIGHT,
+      height,
     );
 
     await Promise.all(
       // eslint-disable-next-line consistent-return
       block.transactionHashes.map(async (transactionHash, i) => {
         if (await isTransactionHashWithdraw(transactionHash)) {
           const siblingPathTransactionHash =
-            updatedTransctionHashesTimber.getSiblingPath(transactionHash);
+            updatedTransactionHashesTimber.getSiblingPath(transactionHash);
           return setTransactionHashSiblingInfo(
             transactionHash,
             siblingPathTransactionHash,
             transactionHashesTimber.leafCount + i,
-            updatedTransctionHashesTimber.root,
+            updatedTransactionHashesTimber.root,
           );
         }
       }),