From 213fcf91f751e20de31ff50b879be2c75b407747 Mon Sep 17 00:00:00 2001
From: C-3PO <c-3po@jedipedia.net>
Date: Thu, 5 Jul 2018 03:01:45 +0200
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=9B=20Fix=20decrypt=20chunk?=
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---
 src/ssn/decryption/decryptChunk.ts | 4 +---
 src/ssn/extractFileStream.ts       | 5 ++++-
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/ssn/decryption/decryptChunk.ts b/src/ssn/decryption/decryptChunk.ts
index 5289c53..5079f64 100644
--- a/src/ssn/decryption/decryptChunk.ts
+++ b/src/ssn/decryption/decryptChunk.ts
@@ -1,14 +1,12 @@
 import updateKeys from './lib/updateKeys';
 
 export default function decryptChunk(encryptedChunk: Buffer, [key0, key1, key2]: [number, number, number]): {decryptedChunk: Buffer, keys: [number, number, number]} {
-  const dv = new DataView(encryptedChunk.buffer);
-
   const decryptedChunk = Buffer.alloc(encryptedChunk.length);
   const dvOut = new DataView(decryptedChunk.buffer);
 
   for (let i = 0; i < encryptedChunk.length; i += 1) {
     //read and decrypt byte
-    let curChar = dv.getUint8(i);
+    let curChar = encryptedChunk.readUInt8(i);
     const keyPart = (key2 | 2) & 0xFFFF;
     const decryptedByte = (keyPart * (keyPart ^ 1)) >>> 8;
     curChar ^= decryptedByte & 0xFF;
diff --git a/src/ssn/extractFileStream.ts b/src/ssn/extractFileStream.ts
index 8b6689b..a934d85 100644
--- a/src/ssn/extractFileStream.ts
+++ b/src/ssn/extractFileStream.ts
@@ -16,7 +16,7 @@ export default function extractFileStream(file: ISsnFileEntry, inputStream: stre
   //Local file header signature
   const magic = localFileHeader.readUInt32LE(0);
   if (magic !== 0x04034B50) {
-    throw new Error(`Local file header had wrong magic; expected 0x04034B50 but got 0x${magic.toString(16).padStart(8, '0')}`);
+    throw new Error(`Local file header had wrong magic; expected 0x04034B50 but got 0x${magic.toString(16).padStart(8, '0')}.`);
   }
   //All fields in the local file header are copies of the central file header, so we can skip them.
   //FIXME: Maybe we should actually read these fields to verify that they are identical?
@@ -44,6 +44,9 @@ export default function extractFileStream(file: ISsnFileEntry, inputStream: stre
 
   //pipe into decompression
   const decompressTransform = zlib.createInflateRaw();
+  decompressTransform.on('error', (error) => {
+    throw new Error(`Error during decompression: ${error.message}`);
+  });
   curStream.pipe(decompressTransform);
   curStream = decompressTransform;