From 359b1093bcf674987abde97c3035789646cbccd3 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 12 Feb 2026 15:47:30 +0000
Subject: [PATCH] Add named constants for WinZip AES extra data magic numbers

Co-authored-by: adamhathcock <527620+adamhathcock@users.noreply.github.com>
---
 src/SharpCompress/Common/Zip/ZipEntry.cs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/SharpCompress/Common/Zip/ZipEntry.cs b/src/SharpCompress/Common/Zip/ZipEntry.cs
index b9507036..47df7d9e 100644
--- a/src/SharpCompress/Common/Zip/ZipEntry.cs
+++ b/src/SharpCompress/Common/Zip/ZipEntry.cs
@@ -10,6 +10,10 @@ public class ZipEntry : Entry
 {
     private readonly ZipFilePart? _filePart;
 
+    // WinZip AES extra data constants
+    private const int MinimumWinZipAesExtraDataLength = 7;
+    private const int WinZipAesCompressionMethodOffset = 5;
+
     internal ZipEntry(ZipFilePart? filePart, IReaderOptions readerOptions)
         : base(readerOptions)
     {
@@ -70,7 +74,7 @@ public class ZipEntry : Entry
             x.Type == ExtraDataType.WinZipAes
         );
 
-        if (aesExtraData is null || aesExtraData.DataBytes.Length < 7)
+        if (aesExtraData is null || aesExtraData.DataBytes.Length < MinimumWinZipAesExtraDataLength)
         {
             return ZipCompressionMethod.WinzipAes;
         }
@@ -78,7 +82,7 @@ public class ZipEntry : Entry
         // The compression method is at offset 5 in the extra data
         return (ZipCompressionMethod)
             System.Buffers.Binary.BinaryPrimitives.ReadUInt16LittleEndian(
-                aesExtraData.DataBytes.AsSpan(5)
+                aesExtraData.DataBytes.AsSpan(WinZipAesCompressionMethodOffset)
             );
     }