Pkware encryption for Zip files didn't allow for multiple reads of an entry

[alexmgerasimov]

Hello!

I tried to use this library and faced some issues. Basically repeated reading of some zip archive entries leads to crashes. It seems that this is related to encrypted zips somehow. I'm using the following test code to reproduce the crashes:

	class Program
	{
		static void Main(string[] args)
		{
			try
			{
				using (var fileStream = File.Open(@"c:\Archive1.zip", FileMode.Open))
					UnpackMultipleTimes(fileStream, "12345678");
			}
			catch (Exception e)
			{				
			}
		}

		private static void UnpackMultipleTimes(Stream stream, string password)
		{
			using (var archive = ArchiveFactory.Open(stream, new ReaderOptions {Password = password}))
			{
				var entries = archive.Entries.Where(entry => !entry.IsDirectory);

				foreach (var entry in entries)
				{
					for (int i = 0; i < 100; i++)
					{
						using (var memoryStream = new MemoryStream())
						using (var entryStream = entry.OpenEntryStream())
						{
							entryStream.CopyTo(memoryStream);
						}
					}
				}
			}
		}
	}

Exception from Archive1.zip:

SharpCompress.Compressors.Deflate.ZlibException was unhandled
HResult=-2146233088
Message=Bad state (invalid block type)
Source=SharpCompress
StackTrace:
в SharpCompress.Compressors.Deflate.InflateManager.Inflate(FlushType flush)
в SharpCompress.Compressors.Deflate.ZlibBaseStream.Read(Byte[] buffer, Int32 offset, Int32 count)
в System.IO.Stream.InternalCopyTo(Stream destination, Int32 bufferSize)
в SevenZipTest.Program.UnpackMultipleTimes(Stream stream, String password)
в SevenZipTest.Program.Main(String[] args)
в System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
в System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
в Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
в System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
в System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
в System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
в System.Threading.ThreadHelper.ThreadStart()

I have several other archives with confidential data and can't share them. They produce exceptions with another messages. For example:

SharpCompress.Compressors.Deflate.ZlibException was unhandled
HResult=-2146233088
Message=Bad state (invalid literal/length code)
Source=SharpCompress
StackTrace:
в SharpCompress.Compressors.Deflate.InflateManager.Inflate(FlushType flush)
в SharpCompress.Compressors.Deflate.ZlibBaseStream.Read(Byte[] buffer, Int32 offset, Int32 count)
в System.IO.Stream.InternalCopyTo(Stream destination, Int32 bufferSize)
в SevenZipTest.Program.UnpackMultipleTimes(Stream stream, String password)
в SevenZipTest.Program.Main(String[] args)
в System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
в System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
в Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
в System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
в System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
в System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
в System.Threading.ThreadHelper.ThreadStart()

Can you fix this, please?

[adamhathcock]

I reproduced this.

This is specific to PKWare encryption as the encryptor is stateful and reused on multiple runs. I'll fix that.

I'm still getting an error. Probably something else is stateful and needs to be reset.

[alexmgerasimov]

Thank you for the quick response!
Is there any chance you can fix this issues in the near future?

[adamhathcock]

I'm doing this in my free time as I take breaks from work. Not sure when I'll fix it. This one I haven't figured out yet.

[alexmgerasimov]

Thank you for merging our pull request to the master!
Can you please advise when the new version of the Nuget package will be released?

[adamhathcock]

I will try to do a release Monday.