From eda01fe188baaf6d860a67cbd4cbad54bb5f9426 Mon Sep 17 00:00:00 2001
From: Denys Zhuravel <derwasp@users.noreply.github.com>
Date: Tue, 14 Jun 2022 15:31:36 +0000
Subject: [PATCH 1/6] Set the ExternalAttributes to the values from the file.

We need to set the external attributes to the *exact* values that the files have. Otherwise if we create a ZipArchive entry and set something there this would get added to the file values and this is not what we want.
---
 .../IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs  | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs b/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
index d2e4f44a6751af..7aca1d0566810c 100644
--- a/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
+++ b/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
@@ -10,7 +10,7 @@ static partial void SetExternalAttributes(FileStream fs, ZipArchiveEntry entry)
             Interop.Sys.FileStatus status;
             Interop.CheckIo(Interop.Sys.FStat(fs.SafeFileHandle, out status), fs.Name);
 
-            entry.ExternalAttributes |= status.Mode << 16;
+            entry.ExternalAttributes = status.Mode << 16;
         }
     }
 }

From 632b85867b9994c6ac98d1caa7ad8f6ca09aa21f Mon Sep 17 00:00:00 2001
From: Denys Zhuravel <derwasp@users.noreply.github.com>
Date: Mon, 27 Jun 2022 20:44:03 +0000
Subject: [PATCH 2/6] Add an assert of te SetExternalAttributes

---
 .../Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs   | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs b/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
index 7aca1d0566810c..32aa2571f2f3fb 100644
--- a/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
+++ b/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
@@ -1,12 +1,16 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
+
 namespace System.IO.Compression
 {
     public static partial class ZipFileExtensions
     {
         static partial void SetExternalAttributes(FileStream fs, ZipArchiveEntry entry)
         {
+            Debug.Assert(!OperatingSystem.IsWindows());
+
             Interop.Sys.FileStatus status;
             Interop.CheckIo(Interop.Sys.FStat(fs.SafeFileHandle, out status), fs.Name);
 

From b3976f1f3efc0117521bfa0fc937790c132f9825 Mon Sep 17 00:00:00 2001
From: Denys Zhuravel <derwasp@users.noreply.github.com>
Date: Mon, 27 Jun 2022 20:46:35 +0000
Subject: [PATCH 3/6] Move the constants into separate files

---
 .../src/System.IO.Compression.csproj          |  2 ++
 .../IO/Compression/ZipArchiveEntry.Unix.cs    |  2 --
 .../IO/Compression/ZipArchiveEntry.Windows.cs |  2 --
 .../System/IO/Compression/ZipArchiveEntry.cs  |  2 ++
 .../ZipArchiveEntryConstants.Unix.cs          | 25 +++++++++++++++++++
 .../ZipArchiveEntryConstants.Windows.cs       | 22 ++++++++++++++++
 6 files changed, 51 insertions(+), 4 deletions(-)
 create mode 100644 src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs
 create mode 100644 src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs

diff --git a/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj b/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
index 7d2ba356485680..81c00261df49cd 100644
--- a/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
+++ b/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
@@ -45,12 +45,14 @@
   <!-- Windows specific files -->
   <ItemGroup Condition="'$(TargetPlatformIdentifier)' == 'windows'">
     <Compile Include="System\IO\Compression\ZipArchiveEntry.Windows.cs" />
+    <Compile Include="System\IO\Compression\ZipArchiveEntryConstants.Windows.cs" />
     <Compile Include="$(CommonPath)Interop\Windows\Interop.Libraries.cs"
              Link="Common\Interop\Windows\Interop.Libraries.cs" />
   </ItemGroup>
   <!-- Unix specific files -->
   <ItemGroup Condition="'$(TargetPlatformIdentifier)' == 'Unix' or '$(TargetPlatformIdentifier)' == 'Browser'">
     <Compile Include="System\IO\Compression\ZipArchiveEntry.Unix.cs" />
+    <Compile Include="System\IO\Compression\ZipArchiveEntryConstants.Unix.cs" />
     <Compile Include="$(CommonPath)Interop\Unix\Interop.Libraries.cs"
              Link="Common\Interop\Unix\Interop.Libraries.cs" />
     <Compile Include="$(CommonPath)Interop\Unix\System.Native\Interop.PathConf.cs"
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Unix.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Unix.cs
index 68e4b5fb17edf6..cad148f6b4a619 100644
--- a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Unix.cs
+++ b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Unix.cs
@@ -5,8 +5,6 @@ namespace System.IO.Compression
 {
     public partial class ZipArchiveEntry
     {
-        internal const ZipVersionMadeByPlatform CurrentZipPlatform = ZipVersionMadeByPlatform.Unix;
-
         /// <summary>
         /// To get the file name of a ZipArchiveEntry, we should be parsing the FullName based
         /// on the path specifications and requirements of the OS that ZipArchive was created on.
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Windows.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Windows.cs
index 730ade4b35081c..c617e00543bec6 100644
--- a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Windows.cs
+++ b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Windows.cs
@@ -5,8 +5,6 @@ namespace System.IO.Compression
 {
     public partial class ZipArchiveEntry
     {
-        internal const ZipVersionMadeByPlatform CurrentZipPlatform = ZipVersionMadeByPlatform.Windows;
-
         /// <summary>
         /// To get the file name of a ZipArchiveEntry, we should be parsing the FullName based
         /// on the path specifications and requirements of the OS that ZipArchive was created on.
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs
index f58bd778a1c026..710fc659efeb1f 100644
--- a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs
+++ b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs
@@ -9,6 +9,8 @@
 using System.Threading;
 using System.Threading.Tasks;
 
+using static System.IO.Compression.ZipArchiveEntryConstants;
+
 namespace System.IO.Compression
 {
     // The disposable fields that this class owns get disposed when the ZipArchive it belongs to gets disposed
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs
new file mode 100644
index 00000000000000..8da9934e06a0e7
--- /dev/null
+++ b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs
@@ -0,0 +1,25 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace System.IO.Compression
+{
+    internal static partial class ZipArchiveEntryConstants
+    {
+        internal const ZipVersionMadeByPlatform CurrentZipPlatform = ZipVersionMadeByPlatform.Unix;
+
+        /// <summary>
+        /// The default external file attributes are used to support zip archives on multiple platforms.
+        /// </summary>
+        internal const UnixFileMode DefaultFileEntryPermissions = UnixFileMode.UserRead | UnixFileMode.UserWrite
+                                                            | UnixFileMode.GroupRead
+                                                            | UnixFileMode.OtherRead;
+
+        /// <summary>
+        /// The default external directory attributes are used to support zip archives on multiple platforms.
+        /// Directories on Unix require the execute permissions to get into them.
+        /// </summary>
+        internal const UnixFileMode DefaultDirectoryEntryPermissions = UnixFileMode.UserRead | UnixFileMode.UserWrite | UnixFileMode.UserExecute
+                                                               | UnixFileMode.GroupRead | UnixFileMode.GroupExecute
+                                                               | UnixFileMode.OtherRead | UnixFileMode.OtherExecute;
+    }
+}
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs
new file mode 100644
index 00000000000000..6f8f104d35ed32
--- /dev/null
+++ b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs
@@ -0,0 +1,22 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace System.IO.Compression
+{
+    internal static partial class ZipArchiveEntryConstants
+    {
+        internal const ZipVersionMadeByPlatform CurrentZipPlatform = ZipVersionMadeByPlatform.Windows;
+
+        /// <summary>
+        /// The default external file attributes are used to support zip archives on multiple platforms.
+        /// Since Windows doesn't use file permissions, there's no default value needed.
+        /// </summary>
+        internal const UnixFileMode DefaultFileEntryPermissions = UnixFileMode.None;
+
+        /// <summary>
+        /// The default external directory attributes are used to support zip archives on multiple platforms.
+        /// Since Windows doesn't use file permissions, there's no default value needed.
+        /// </summary>
+        internal const UnixFileMode DefaultDirectoryEntryPermissions = UnixFileMode.None;
+    }
+}

From 139850e65ce09d9eb36409d3c5b577234437d8b9 Mon Sep 17 00:00:00 2001
From: Denys Zhuravel <derwasp@users.noreply.github.com>
Date: Mon, 27 Jun 2022 20:47:00 +0000
Subject: [PATCH 4/6] Add a test verifying the new behavior

---
 .../tests/System.IO.Compression.Tests.csproj  |  4 ++++
 .../tests/ZipArchive/zip_CreateTests.Unix.cs  | 22 +++++++++++++++++++
 2 files changed, 26 insertions(+)
 create mode 100644 src/libraries/System.IO.Compression/tests/ZipArchive/zip_CreateTests.Unix.cs

diff --git a/src/libraries/System.IO.Compression/tests/System.IO.Compression.Tests.csproj b/src/libraries/System.IO.Compression/tests/System.IO.Compression.Tests.csproj
index adac7a348c6922..229119e3aa37cf 100644
--- a/src/libraries/System.IO.Compression/tests/System.IO.Compression.Tests.csproj
+++ b/src/libraries/System.IO.Compression/tests/System.IO.Compression.Tests.csproj
@@ -41,6 +41,10 @@
     <Compile Include="$(CommonPath)System\Net\MultiArrayBuffer.cs" Link="ProductionCode\Common\System\Net\MultiArrayBuffer.cs" />
     <Compile Include="$(CommonPath)System\Net\StreamBuffer.cs" Link="ProductionCode\Common\System\Net\StreamBuffer.cs" />
   </ItemGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' == 'Unix' or '$(TargetPlatformIdentifier)' == 'Browser'">
+    <Compile Include="ZipArchive\zip_CreateTests.Unix.cs" />
+  </ItemGroup>
+
   <ItemGroup>
     <ProjectReference Include="$(CommonTestPath)StreamConformanceTests\StreamConformanceTests.csproj" />
   </ItemGroup>
diff --git a/src/libraries/System.IO.Compression/tests/ZipArchive/zip_CreateTests.Unix.cs b/src/libraries/System.IO.Compression/tests/ZipArchive/zip_CreateTests.Unix.cs
new file mode 100644
index 00000000000000..121ffada3054ee
--- /dev/null
+++ b/src/libraries/System.IO.Compression/tests/ZipArchive/zip_CreateTests.Unix.cs
@@ -0,0 +1,22 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Threading.Tasks;
+using Xunit;
+
+namespace System.IO.Compression.Tests
+{
+    public partial class zip_CreateTests : ZipFileTestBase
+    {
+        [Theory]
+        [InlineData("folder/", 493 << 16)]
+        [InlineData("folder/file", 420 << 16)]
+        [InlineData("folder\\file", 420 << 16)]
+        public static void Verify_Default_Permissions_Are_Applied_For_Entries(string path, int permissions)
+        {
+            using var archive = new ZipArchive(new MemoryStream(), ZipArchiveMode.Create, false);
+            var newEntry = archive.CreateEntry(path);
+            Assert.Equal(newEntry.ExternalAttributes, permissions);
+        }
+    }
+}

From 424127d6ccc95bb49ad69e01e26bbaeb5631af62 Mon Sep 17 00:00:00 2001
From: Denys Zhuravel <derwasp@users.noreply.github.com>
Date: Mon, 27 Jun 2022 20:47:59 +0000
Subject: [PATCH 5/6] Use the new default permissions on the ZipArchiveEntry

---
 .../src/System/IO/Compression/ZipArchiveEntry.cs            | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs
index 710fc659efeb1f..b75af75204aef8 100644
--- a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs
+++ b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs
@@ -117,7 +117,11 @@ internal ZipArchiveEntry(ZipArchive archive, string entryName)
 
             _compressedSize = 0; // we don't know these yet
             _uncompressedSize = 0;
-            _externalFileAttr = 0;
+            UnixFileMode defaultEntryPermissions = entryName.EndsWith(Path.DirectorySeparatorChar) || entryName.EndsWith(Path.AltDirectorySeparatorChar)
+                                        ? DefaultDirectoryEntryPermissions
+                                        : DefaultFileEntryPermissions;
+            _externalFileAttr = (uint)(defaultEntryPermissions) << 16;
+
             _offsetOfLocalHeader = 0;
             _storedOffsetOfCompressedData = null;
             _crc32 = 0;

From 5c8920b20194dbdac30777945cc2e3d8b8776b3d Mon Sep 17 00:00:00 2001
From: Denys Zhuravel <derwasp@users.noreply.github.com>
Date: Mon, 27 Jun 2022 20:56:26 +0000
Subject: [PATCH 6/6] Move the zip constants to the common directory

Move the new zip constants to the common folder and use the constants files in both IO.Compression and IO.Compression.ZipFile
---
 .../System/IO/Compression/ZipArchiveEntryConstants.Unix.cs | 2 --
 .../IO/Compression/ZipArchiveEntryConstants.Windows.cs     | 2 --
 .../src/System.IO.Compression.ZipFile.csproj               | 1 +
 .../ZipFileExtensions.ZipArchive.Create.Unix.cs            | 7 +++++++
 .../System.IO.Compression/src/System.IO.Compression.csproj | 4 ++--
 .../src/System/IO/Compression/ZipArchiveEntry.Unix.cs      | 2 ++
 .../src/System/IO/Compression/ZipArchiveEntry.Windows.cs   | 2 ++
 7 files changed, 14 insertions(+), 6 deletions(-)
 rename src/libraries/{System.IO.Compression => Common}/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs (92%)
 rename src/libraries/{System.IO.Compression => Common}/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs (89%)

diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs b/src/libraries/Common/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs
similarity index 92%
rename from src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs
rename to src/libraries/Common/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs
index 8da9934e06a0e7..6097961679a85c 100644
--- a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs
+++ b/src/libraries/Common/src/System/IO/Compression/ZipArchiveEntryConstants.Unix.cs
@@ -5,8 +5,6 @@ namespace System.IO.Compression
 {
     internal static partial class ZipArchiveEntryConstants
     {
-        internal const ZipVersionMadeByPlatform CurrentZipPlatform = ZipVersionMadeByPlatform.Unix;
-
         /// <summary>
         /// The default external file attributes are used to support zip archives on multiple platforms.
         /// </summary>
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs b/src/libraries/Common/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs
similarity index 89%
rename from src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs
rename to src/libraries/Common/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs
index 6f8f104d35ed32..5f685313e7bc5c 100644
--- a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs
+++ b/src/libraries/Common/src/System/IO/Compression/ZipArchiveEntryConstants.Windows.cs
@@ -5,8 +5,6 @@ namespace System.IO.Compression
 {
     internal static partial class ZipArchiveEntryConstants
     {
-        internal const ZipVersionMadeByPlatform CurrentZipPlatform = ZipVersionMadeByPlatform.Windows;
-
         /// <summary>
         /// The default external file attributes are used to support zip archives on multiple platforms.
         /// Since Windows doesn't use file permissions, there's no default value needed.
diff --git a/src/libraries/System.IO.Compression.ZipFile/src/System.IO.Compression.ZipFile.csproj b/src/libraries/System.IO.Compression.ZipFile/src/System.IO.Compression.ZipFile.csproj
index 3287498e587c16..b573949d699958 100644
--- a/src/libraries/System.IO.Compression.ZipFile/src/System.IO.Compression.ZipFile.csproj
+++ b/src/libraries/System.IO.Compression.ZipFile/src/System.IO.Compression.ZipFile.csproj
@@ -25,6 +25,7 @@
   <ItemGroup Condition="'$(TargetPlatformIdentifier)' == ''">
     <Compile Include="System\IO\Compression\ZipFileExtensions.ZipArchive.Create.Unix.cs" />
     <Compile Include="System\IO\Compression\ZipFileExtensions.ZipArchiveEntry.Extract.Unix.cs" />
+    <Compile Include="$(CommonPath)System\IO\Compression\ZipArchiveEntryConstants.Unix.cs" />
     <Compile Include="$(CommonPath)Interop\Unix\Interop.IOErrors.cs"
              Link="Common\Interop\Unix\Interop.IOErrors.cs" />
     <Compile Include="$(CommonPath)Interop\Unix\Interop.Libraries.cs"
diff --git a/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs b/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
index 32aa2571f2f3fb..0b22b08606536f 100644
--- a/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
+++ b/src/libraries/System.IO.Compression.ZipFile/src/System/IO/Compression/ZipFileExtensions.ZipArchive.Create.Unix.cs
@@ -3,6 +3,8 @@
 
 using System.Diagnostics;
 
+using static System.IO.Compression.ZipArchiveEntryConstants;
+
 namespace System.IO.Compression
 {
     public static partial class ZipFileExtensions
@@ -11,6 +13,11 @@ static partial void SetExternalAttributes(FileStream fs, ZipArchiveEntry entry)
         {
             Debug.Assert(!OperatingSystem.IsWindows());
 
+            // SetExternalAttributes is only used to overwrite the default values when reading on the unix systems
+            // This assert ensures that nothing else sets values different to the default before
+            // overwriting it with the data read from the files
+            Debug.Assert(entry.ExternalAttributes == ((uint)DefaultFileEntryPermissions << 16));
+
             Interop.Sys.FileStatus status;
             Interop.CheckIo(Interop.Sys.FStat(fs.SafeFileHandle, out status), fs.Name);
 
diff --git a/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj b/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
index 81c00261df49cd..80007bcfe5f772 100644
--- a/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
+++ b/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
@@ -45,14 +45,14 @@
   <!-- Windows specific files -->
   <ItemGroup Condition="'$(TargetPlatformIdentifier)' == 'windows'">
     <Compile Include="System\IO\Compression\ZipArchiveEntry.Windows.cs" />
-    <Compile Include="System\IO\Compression\ZipArchiveEntryConstants.Windows.cs" />
+    <Compile Include="$(CommonPath)System\IO\Compression\ZipArchiveEntryConstants.Windows.cs" />
     <Compile Include="$(CommonPath)Interop\Windows\Interop.Libraries.cs"
              Link="Common\Interop\Windows\Interop.Libraries.cs" />
   </ItemGroup>
   <!-- Unix specific files -->
   <ItemGroup Condition="'$(TargetPlatformIdentifier)' == 'Unix' or '$(TargetPlatformIdentifier)' == 'Browser'">
     <Compile Include="System\IO\Compression\ZipArchiveEntry.Unix.cs" />
-    <Compile Include="System\IO\Compression\ZipArchiveEntryConstants.Unix.cs" />
+    <Compile Include="$(CommonPath)System\IO\Compression\ZipArchiveEntryConstants.Unix.cs" />
     <Compile Include="$(CommonPath)Interop\Unix\Interop.Libraries.cs"
              Link="Common\Interop\Unix\Interop.Libraries.cs" />
     <Compile Include="$(CommonPath)Interop\Unix\System.Native\Interop.PathConf.cs"
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Unix.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Unix.cs
index cad148f6b4a619..68e4b5fb17edf6 100644
--- a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Unix.cs
+++ b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Unix.cs
@@ -5,6 +5,8 @@ namespace System.IO.Compression
 {
     public partial class ZipArchiveEntry
     {
+        internal const ZipVersionMadeByPlatform CurrentZipPlatform = ZipVersionMadeByPlatform.Unix;
+
         /// <summary>
         /// To get the file name of a ZipArchiveEntry, we should be parsing the FullName based
         /// on the path specifications and requirements of the OS that ZipArchive was created on.
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Windows.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Windows.cs
index c617e00543bec6..730ade4b35081c 100644
--- a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Windows.cs
+++ b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.Windows.cs
@@ -5,6 +5,8 @@ namespace System.IO.Compression
 {
     public partial class ZipArchiveEntry
     {
+        internal const ZipVersionMadeByPlatform CurrentZipPlatform = ZipVersionMadeByPlatform.Windows;
+
         /// <summary>
         /// To get the file name of a ZipArchiveEntry, we should be parsing the FullName based
         /// on the path specifications and requirements of the OS that ZipArchive was created on.