🔖 Merkle Root Calculation

SummerOfBitcoin · May 8, 2024 · e65ef5b · e65ef5b
1 parent ba9caaf
commit e65ef5b
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Showing 20 changed files with 706 additions and 585 deletions.
diff --git a/package.json b/package.json
@@ -10,6 +10,8 @@
   "author": "",
   "license": "ISC",
   "dependencies": {
+    "@bitcoinerlab/secp256k1": "^1.1.1",
+    "asn1js": "^3.0.5",
     "bitcoinjs-lib": "^6.1.5",
     "ecpair": "^2.1.0",
     "lodash.clonedeep": "^4.5.0",

diff --git a/src/constants.ts b/src/constants.ts
@@ -1,2 +1,7 @@
-const DIFFICULTY =
+export const DIFFICULTY =
   "0000ffff00000000000000000000000000000000000000000000000000000000";
+
+export const WITNESS_RESERVED_VALUE =
+  "0000000000000000000000000000000000000000000000000000000000000000";
+
+export const MAX_VALUE = 0xffffffff;
diff --git a/src/features/block/coinbaseTransaction.ts b/src/features/block/coinbaseTransaction.ts
@@ -1,48 +1,48 @@
-import { Transaction } from "../../types";
+// import { Transaction } from "../../types";
+import { MAX_VALUE, WITNESS_RESERVED_VALUE } from "../../constants";
 import { compactSize } from "../encoding/compactSize";
+import { Input, Output, Transaction } from "../transaction";
 
-export const ZEROS =
-  "0000000000000000000000000000000000000000000000000000000000000000";
-const MAX_VALUE = 0xffffffff;
-const height = 538403;
+// export const ZEROS =
+//   "0000000000000000000000000000000000000000000000000000000000000000";
+// const MAX_VALUE = 0xffffffff;
+// const height = 538403;
 const blockReward = 1250000000;
 
-const coinbaseTemplate = {
-  version: 0,
-  locktime: 0,
-  vin: [
-    {
-      txid: ZEROS,
-      vout: MAX_VALUE,
-      prevout: null,
-      scriptsig: "03233708",
-      scriptsig_asm: "OP_PUSHBYTES_3 233708",
-      witness: [ZEROS],
-    },
-  ],
-  vout: [
-    {
-      scriptpubkey: "76a914edf10a7fac6b32e24daa5305c723f3de58db1bc888ac",
-      scriptpubkey_asm:
-        "OP_DUP OP_HASH160 OP_PUSHBYTES_20 edf10a7fac6b32e24daa5305c723f3de58db1bc8 OP_EQUALVERIFY OP_CHECKSIG",
-      scriptpubkey_type: "p2pkh",
-      value: blockReward,
-    },
-    {
-      //op return push 36 bytes 4 btyes commitment + hash256 of witness merkle root + zeros
-      scriptpubkey: "6a24aa21a9ed", // add the witness commitment later
-      scriptpubkey_type: "op_return",
-      value: 0,
-    },
-  ],
-} as unknown as Transaction;
-
 export const generateCoinbaseTransaction = (
   totalFee: number,
   commitmentHeader: string
 ) => {
-  coinbaseTemplate.vout[1].scriptpubkey = `6a24aa21a9ed${commitmentHeader}`;
-  coinbaseTemplate.vout[0].value = blockReward + totalFee;
+  const transaction = new Transaction(0, 0);
+  const input = new Input({
+    txid: WITNESS_RESERVED_VALUE,
+    vout: MAX_VALUE,
+    prevout: null,
+    scriptsig: "03233708", //block number is 233708
+    scriptsig_asm: "OP_PUSHBYTES_3 233708",
+    witness: [WITNESS_RESERVED_VALUE],
+    sequence: 0,
+    is_coinbase: true,
+  });
+
+  const output1 = new Output({
+    scriptpubkey: "76a914edf10a7fac6b32e24daa5305c723f3de58db1bc888ac",
+    scriptpubkey_asm:
+      "OP_DUP OP_HASH160 OP_PUSHBYTES_20 edf10a7fac6b32e24daa5305c723f3de58db1bc8 OP_EQUALVERIFY OP_CHECKSIG",
+    scriptpubkey_type: "p2pkh",
+    value: blockReward + totalFee,
+  });
+
+  const output2 = new Output({
+    scriptpubkey: "6a24aa21a9ed" + commitmentHeader,
+    scriptpubkey_asm: "OP_RETURN OP_PUSHBYTES_36 aa21a9ed" + commitmentHeader,
+    scriptpubkey_type: "op_return",
+    value: 0,
+  });
+
+  transaction.addInput(input);
+  transaction.addOutput(output1);
+  transaction.addOutput(output2);
 
-  return coinbaseTemplate;
+  return transaction;
 };
diff --git a/src/features/block/fee.ts b/src/features/block/fee.ts
@@ -1,12 +1,12 @@
-import { Transaction } from "../../types";
-import { txWeight } from "../encoding/serializer";
+import { Transaction } from "../transaction";
 
 export const totalFee = (txs: Transaction[]) => {
   let inputValues = 0;
   let outputValues = 0;
 
   for (const tx of txs) {
     for (const input of tx.vin) {
+      if (!input.prevout) continue;
       inputValues += input.prevout.value;
     }
     for (const output of tx.vout) {
@@ -20,12 +20,13 @@ export const totalFee = (txs: Transaction[]) => {
 export const feePerByte = (tx: Transaction) => {
   let fee = 0;
   for (const input of tx.vin) {
+    if (!input.prevout) continue;
     fee += input.prevout.value;
   }
 
   for (const output of tx.vout) {
     fee -= output.value;
   }
 
-  return fee / txWeight(tx);
+  return fee / tx.weight;
 };
diff --git a/src/features/block/merkleRoot.ts b/src/features/block/merkleRoot.ts
@@ -1,6 +1,4 @@
-import { Transaction } from "../../types";
-import { reversify, sha256 } from "../../utils";
-import { txSerializer } from "../encoding/serializer";
+import { sha256 } from "../../utils";
 
 export const merkleRoot = (txs: string[]) => {
   let curr = txs;

diff --git a/src/features/block/mine.ts b/src/features/block/mine.ts
@@ -1,9 +1,9 @@
 import { reversify, sha256 } from "../../utils";
-import { Transaction } from "../../types";
+import { Transaction } from "../transaction";
 import { merkleRoot } from "./merkleRoot";
-import { txSerializer } from "../encoding/serializer";
-import { ZEROS, generateCoinbaseTransaction } from "./coinbaseTransaction";
+import { generateCoinbaseTransaction } from "./coinbaseTransaction";
 import { totalFee } from "./fee";
+import { DIFFICULTY, WITNESS_RESERVED_VALUE } from "../../constants";
 
 export const mine = (
   txs: Transaction[]
@@ -16,27 +16,25 @@ export const mine = (
     "0000ffff00000000000000000000000000000000000000000000000000000000";
   const version = Buffer.alloc(4);
   version.writeInt32LE(4);
-  //make it the same as the difficulty
 
-  const witnessMerkleRootHash = reversify(
-    merkleRoot([
-      ZEROS, //zeros are for the coinbase transaction
-      ...txs.map((tx) =>
-        reversify(sha256(sha256(txSerializer(tx).serializedWTx)))
-      ),
-    ])
+  // const witnessMerkleRootHash = merkleRoot([
+  //   ZEROS, //zeros are for the coinbase transaction
+  //   ...txs.map((tx) => sha256(sha256(txSerializer(tx).serializedWTx))),
+  // ]);
+  const witnessMerkleRootHash = merkleRoot([
+    WITNESS_RESERVED_VALUE,
+    ...txs.map((tx) => reversify(tx.wtxid)),
+  ]);
+  const commitmentHash = sha256(
+    sha256(witnessMerkleRootHash + WITNESS_RESERVED_VALUE)
   );
-  const commitmentHash = sha256(sha256(witnessMerkleRootHash + ZEROS));
   const fees = totalFee(txs);
   const coinbaseTransaction = generateCoinbaseTransaction(fees, commitmentHash);
 
-  const prevBlockHash =
-    "0000ffff00000000000000000000000000000000000000000000000000000000"; //make it the same as the difficulty
+  const prevBlockHash = DIFFICULTY; //make it the same as the difficulty
 
   const merkleRootHash = merkleRoot(
-    [coinbaseTransaction, ...txs].map((tx) =>
-      sha256(sha256(txSerializer(tx).serializedTx))
-    )
+    [coinbaseTransaction, ...txs].map((tx) => reversify(tx.txid))
   );
 
   const time = Buffer.alloc(4);
@@ -54,7 +52,6 @@ export const mine = (
       "hex"
     )}${nonceBuf.toString("hex")}`;
 
-    // console.log(serializedBlock);
     const blockHash = reversify(sha256(sha256(serializedBlock)));
     if (
       Buffer.from(difficulty, "hex").compare(Buffer.from(blockHash, "hex")) < 0