From 2a0c9416c0f7977fc5aa7f06c1fcb9d1c6cc9c2b Mon Sep 17 00:00:00 2001
From: Nesopie <aymanshaik1015@gmail.com>
Date: Thu, 28 Mar 2024 08:18:41 +0530
Subject: [PATCH] chore: change sha256 to sha160

---
 src/features/validator/hash.ts      | 21 ++++++++++++++-------
 src/features/validator/signature.ts |  4 ++--
 src/utils.ts                        | 15 ++++++---------
 3 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/src/features/validator/hash.ts b/src/features/validator/hash.ts
index d709b2a..925b09d 100644
--- a/src/features/validator/hash.ts
+++ b/src/features/validator/hash.ts
@@ -1,8 +1,14 @@
-import { Transaction, TransactionType } from "../../types";
+import { TransactionType } from "../../types";
 import * as crypto from "crypto";
-import { asmToHex, hash256, sha256 } from "../../utils";
+import { asmToHex, hash160, sha256 } from "../../utils";
 import { OP_CODES } from "../script/op_codes";
 import { collapseTextChangeRangesAcrossMultipleVersions } from "typescript";
+import { Transaction } from "../transaction";
+
+//in p2sh p2wsh
+//sha256(inner witness script) = last part of inneer redeem script
+//hash160 of the inner redeem script should be equal to the hash in the script pubkey
+//eg 0d9ef76964c23e940ebcddde868c1089dfdb52147364da01ee92438dfb7c9375
 
 export const HashValidator = (tx: Transaction) => {
   let lockingScript = "";
@@ -11,12 +17,13 @@ export const HashValidator = (tx: Transaction) => {
   let publicKey = "";
 
   for (const input of tx.vin) {
+    if (!input.prevout) continue;
     switch (input.prevout.scriptpubkey_type) {
       case TransactionType.P2PKH:
         const scriptAsmTokens = input.scriptsig_asm.split(" ");
         publicKey = scriptAsmTokens[scriptAsmTokens.length - 1];
 
-        hash = hash256(publicKey);
+        hash = hash160(publicKey);
 
         lockingScript = input.prevout.scriptpubkey;
         script = `${OP_CODES.OP_DUP}${OP_CODES.OP_HASH160}${OP_CODES.OP_PUSHBYTES_20}${hash}${OP_CODES.OP_EQUALVERIFY}${OP_CODES.OP_CHECKSIG}`;
@@ -28,27 +35,27 @@ export const HashValidator = (tx: Transaction) => {
         const hex = asmToHex(inputScript[inputScript.length - 1]);
         lockingScript = input.prevout.scriptpubkey;
 
-        const scriptHash = hash256(hex);
+        const scriptHash = hash160(hex);
 
         script = `${OP_CODES.OP_HASH160}${OP_CODES.OP_PUSHBYTES_20}${scriptHash}${OP_CODES.OP_EQUAL}`;
         if (script !== lockingScript) return false;
         break;
       case TransactionType.P2WPKH:
+        if (!input.witness || !input.witness[1]) return false;
         publicKey = input.witness[1];
-        if (!publicKey) return false;
 
-        hash = hash256(publicKey);
+        hash = hash160(publicKey);
         lockingScript = input.prevout.scriptpubkey;
         script = `${OP_CODES.OP_0}${OP_CODES.OP_PUSHBYTES_20}${hash}`;
 
         if (script !== lockingScript) return false;
         break;
       case TransactionType.P2WSH:
+        if (!input.witness) return false;
         const witnessScript = input.witness[input.witness.length - 1];
         if (!witnessScript) return false;
 
         lockingScript = input.prevout.scriptpubkey;
-        //OP_0 OP_PUSHBYTES_32 0b685cc06add0b2e23bcd67f0bef8d364cdc1abcf6fb126958826a7cfe351bf3
         script = `${OP_CODES.OP_0}${OP_CODES.OP_PUSHBYTES_32}${sha256(
           witnessScript
         )}`;
diff --git a/src/features/validator/signature.ts b/src/features/validator/signature.ts
index 1987e9f..e1ce455 100644
--- a/src/features/validator/signature.ts
+++ b/src/features/validator/signature.ts
@@ -1,6 +1,6 @@
 import { SigHash, TransactionType } from "../../types";
 import { Transaction } from "../transaction";
-import { hash256, sha256 } from "../../utils";
+import { hash160, sha256 } from "../../utils";
 import * as asn1js from "asn1js";
 
 import { ECPairFactory } from "ecpair";
@@ -66,7 +66,7 @@ export const signatureValidator = (tx: Transaction): boolean => {
         if (!input.witness) return false;
         derEncodedSignature = input.witness[0];
         pubkey = input.witness[1];
-        const pubkeyHash = hash256(pubkey);
+        const pubkeyHash = hash160(pubkey);
         const pubkeyInScript = input.prevout.scriptpubkey.slice(4);
 
         if (pubkeyHash !== pubkeyInScript) return false;
diff --git a/src/utils.ts b/src/utils.ts
index f8693b1..14daafb 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -1,7 +1,7 @@
 import * as crypto from "crypto";
 import { OP_CODES } from "./features/script/op_codes";
 
-export const hash256 = (str: string) => {
+export const hash160 = (str: string) => {
   return crypto
     .createHash("ripemd160")
     .update(Buffer.from(sha256(str), "hex"))
@@ -31,11 +31,8 @@ export const reversify = (str: string) => {
     .join("");
 };
 
-// const asm = "OP_0 OP_PUSHBYTES_20 15ff0337937ecadd10ce56ffdfd4674817613223";
-// const hex = asmToHex(asm);
-// console.log(hex);
-// console.log(
-//   sha256(
-//     "201dda24da0b91e0eed9770878c504aeb07628ca4ccae9a7bd5347b96ee85dac52ac0063036f726401010a746578742f706c61696e00357b2270223a226272632d3230222c226f70223a226d696e74222c227469636b223a22646f6765222c22616d74223a2234323030227d68"
-//   )
-// );
+console.log(
+  hash160(
+    "00202791caef68f38a0fa3f14d5f4169894ebc318355d2c33bfc1a9d606403b1dbea"
+  )
+);