From ab5af409996fdde6ea986c738df9eeeeffdeb6d8 Mon Sep 17 00:00:00 2001
From: Robb Pryde <roboy2k@gmail.com>
Date: Sat, 26 Oct 2024 01:22:07 +0100
Subject: [PATCH 1/2] Fixed bug in zip time header flags, and failing to parse
 it no longer throws an exception.

---
 .../Headers/LocalEntryHeaderExtraFactory.cs   | 21 +++++++++++++------
 src/SharpCompress/Common/Zip/ZipEntry.cs      | 21 ++++++++++++++++---
 2 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/src/SharpCompress/Common/Zip/Headers/LocalEntryHeaderExtraFactory.cs b/src/SharpCompress/Common/Zip/Headers/LocalEntryHeaderExtraFactory.cs
index 88e4a187..f90272c4 100644
--- a/src/SharpCompress/Common/Zip/Headers/LocalEntryHeaderExtraFactory.cs
+++ b/src/SharpCompress/Common/Zip/Headers/LocalEntryHeaderExtraFactory.cs
@@ -166,10 +166,10 @@ public UnixTimeExtraField(ExtraDataType type, ushort length, byte[] dataBytes)
                 return Tuple.Create<DateTime?, DateTime?, DateTime?>(null, null, null);
             }
 
-            var flags = DataBytes[0];
-            var isModifiedTimeSpecified = (flags & 0x01) == 1;
-            var isLastAccessTimeSpecified = (flags & 0x02) == 1;
-            var isCreationTimeSpecified = (flags & 0x04) == 1;
+            var flags = (RecordedTimeFlag)DataBytes[0];
+            var isModifiedTimeSpecified = flags.HasFlag(RecordedTimeFlag.LastModified);
+            var isLastAccessTimeSpecified = flags.HasFlag(RecordedTimeFlag.LastAccessed);
+            var isCreationTimeSpecified = flags.HasFlag(RecordedTimeFlag.Created);
             var currentIndex = 1;
             DateTime? modifiedTime = null;
             DateTime? lastAccessTime = null;
@@ -189,7 +189,7 @@ public UnixTimeExtraField(ExtraDataType type, ushort length, byte[] dataBytes)
             {
                 if (currentIndex + 4 > DataBytes.Length)
                 {
-                    throw new ArchiveException("Invalid UnicodeExtraTime field");
+                    return Tuple.Create<DateTime?, DateTime?, DateTime?>(null, null, null);
                 }
 
                 var lastAccessEpochTime = BinaryPrimitives.ReadInt32LittleEndian(
@@ -206,7 +206,7 @@ public UnixTimeExtraField(ExtraDataType type, ushort length, byte[] dataBytes)
             {
                 if (currentIndex + 4 > DataBytes.Length)
                 {
-                    throw new ArchiveException("Invalid UnicodeExtraTime field");
+                    return Tuple.Create<DateTime?, DateTime?, DateTime?>(null, null, null);
                 }
 
                 var creationTimeEpochTime = BinaryPrimitives.ReadInt32LittleEndian(
@@ -222,6 +222,15 @@ public UnixTimeExtraField(ExtraDataType type, ushort length, byte[] dataBytes)
             return Tuple.Create(modifiedTime, lastAccessTime, creationTime);
         }
     }
+
+    [Flags]
+    private enum RecordedTimeFlag
+    {
+        None = 0,
+        LastModified = 1,
+        LastAccessed = 2,
+        Created = 4
+    }
 }
 
 internal static class LocalEntryHeaderExtraFactory
diff --git a/src/SharpCompress/Common/Zip/ZipEntry.cs b/src/SharpCompress/Common/Zip/ZipEntry.cs
index 2700e005..05d1d885 100644
--- a/src/SharpCompress/Common/Zip/ZipEntry.cs
+++ b/src/SharpCompress/Common/Zip/ZipEntry.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using SharpCompress.Common.Zip.Headers;
 
 namespace SharpCompress.Common.Zip;
@@ -15,10 +16,16 @@ internal ZipEntry(ZipFilePart? filePart)
             return;
         }
         _filePart = filePart;
+
         LastModifiedTime = Utility.DosDateToDateTime(
             filePart.Header.LastModifiedDate,
             filePart.Header.LastModifiedTime
         );
+
+        var times = filePart.Header.Extra.FirstOrDefault(header => header.GetType() == typeof(UnixTimeExtraField)) as UnixTimeExtraField;
+
+        LastAccessedTime = times?.UnicodeTimes.Item2;
+        CreatedTime = times?.UnicodeTimes.Item3;
     }
 
     public override CompressionType CompressionType =>
@@ -51,9 +58,17 @@ internal ZipEntry(ZipFilePart? filePart)
 
     public override DateTime? LastModifiedTime { get; }
 
-    public override DateTime? CreatedTime => null;
-
-    public override DateTime? LastAccessedTime => null;
+    /// <inheritdoc/>
+    /// <remarks>
+    /// The returned time is UTC, not local.
+    /// </remarks>
+    public override DateTime? CreatedTime { get; }
+
+    /// <inheritdoc/>
+    /// <remarks>
+    /// The returned time is UTC, not local.
+    /// </remarks>
+    public override DateTime? LastAccessedTime { get; }
 
     public override DateTime? ArchivedTime => null;
 

From 0faa176791939ba9b44c594db9b26b35222322a3 Mon Sep 17 00:00:00 2001
From: Robb Pryde <roboy2k@gmail.com>
Date: Thu, 31 Oct 2024 17:35:47 +0000
Subject: [PATCH 2/2] Sharpier styling

---
 src/SharpCompress/Common/Zip/ZipEntry.cs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/SharpCompress/Common/Zip/ZipEntry.cs b/src/SharpCompress/Common/Zip/ZipEntry.cs
index 05d1d885..802dd19a 100644
--- a/src/SharpCompress/Common/Zip/ZipEntry.cs
+++ b/src/SharpCompress/Common/Zip/ZipEntry.cs
@@ -22,7 +22,10 @@ internal ZipEntry(ZipFilePart? filePart)
             filePart.Header.LastModifiedTime
         );
 
-        var times = filePart.Header.Extra.FirstOrDefault(header => header.GetType() == typeof(UnixTimeExtraField)) as UnixTimeExtraField;
+        var times =
+            filePart.Header.Extra.FirstOrDefault(header =>
+                header.GetType() == typeof(UnixTimeExtraField)
+            ) as UnixTimeExtraField;
 
         LastAccessedTime = times?.UnicodeTimes.Item2;
         CreatedTime = times?.UnicodeTimes.Item3;