fix: Made usage of SyncLock for disposal consistent, added a check fo…

…r a maximum file size and changed some message creations.

TUPWLib/Crypto/CounterModeCryptoTransform.vb

@@ -18,14 +18,15 @@
 '
 ' Author: Frank Schwab, DB Systel GmbH
 '
-' Version: 2.0.1
+' Version: 2.0.2
 '
 ' Change history:
 '    2020-04-30: V1.0.0: Created.
 '    2020-05-12: V1.1.0: Corrected handling of 0 length final block.
 '    2020-06-18: V1.1.1: Corrected handling of null parameters in constructors.
 '    2020-12-10: V2.0.0: Added correct handling of disposed instance.
 '    2020-12-11: V2.0.1: Put IsValid method where it belongs.
+'    2020-12-16: V2.0.2: Made usage of SyncLock for disposal consistent.
 '
 
 Imports System.Security.Cryptography
@@ -54,6 +55,11 @@ Public Class CounterModeCryptoTransform : Implements ICryptoTransform, IDisposab
    Private m_BlockSizeInBytes As Integer
    Private m_XorMask As Byte()
    Private m_XorMaskPosition As Integer
+
+   ''' <summary>
+   ''' Object only used for locking the call to Dispose.
+   ''' </summary>
+   Private ReadOnly m_LockObject As New Object
 #End Region
 
 #Region "Constructor"
@@ -370,6 +376,26 @@ Public Class CounterModeCryptoTransform : Implements ICryptoTransform, IDisposab
          ArrayHelper.Clear(m_Counter)
    End Sub
 #End Region
+
+#Region "Data helpers"
+   ''' <summary>
+   ''' Clear all data.
+   ''' </summary>
+   Private Sub ClearData()
+      m_XorMaskPosition = 0
+
+      ArrayHelper.Clear(m_Counter)
+      ArrayHelper.Clear(m_XorMask)
+
+      m_CounterEncryptor.Dispose()
+      m_SymmetricAlgorithm.Dispose()
+
+      m_Counter = Nothing
+      m_XorMask = Nothing
+      m_CounterEncryptor = Nothing
+      m_SymmetricAlgorithm = Nothing
+   End Sub
+#End Region
 #End Region
 
 #Region "IDisposable Support"
@@ -389,16 +415,10 @@ Public Class CounterModeCryptoTransform : Implements ICryptoTransform, IDisposab
          '
          ' Disposing of resources needs to be synchronized to prevent a race condition.
          '
-         SyncLock m_SymmetricAlgorithm
+         SyncLock m_LockObject
             m_IsDisposed = True
 
-            m_XorMaskPosition = 0
-
-            ArrayHelper.Clear(m_Counter)
-            ArrayHelper.Clear(m_XorMask)
-
-            m_CounterEncryptor.Dispose()
-            m_SymmetricAlgorithm.Dispose()
+            ClearData()
          End SyncLock
 
          ' Free unmanaged resources (unmanaged objects) and override Finalize() below.
@@ -431,9 +451,10 @@ Public Class CounterModeCryptoTransform : Implements ICryptoTransform, IDisposab
    ''' <returns><c>true</c>, if this instance is in a valid state, <c>false</c>, if this instance has already been disposed of.</returns>
    Public ReadOnly Property IsValid As Boolean
       Get
-         Return Not m_IsDisposed
+         SyncLock m_LockObject
+            Return Not m_IsDisposed
+         End SyncLock
       End Get
    End Property
-
 #End Region
 End Class

TUPWLib/Crypto/FileAndKeyEncryption.vb

@@ -18,12 +18,13 @@
 '
 ' Author: Frank Schwab, DB Systel GmbH
 '
-' Version: 2.0.1
+' Version: 2.1.0
 '
 ' Change history:
 '    2020-05-05: V1.0.0: Created.
 '    2020-12-10: V2.0.0: Correct handling of disposed instances.
 '    2020-12-11: V2.0.1: Put IsValid method where it belongs.
+'    2020-12-16: V2.1.0: Made usage of SyncLock for disposal consistent and added check for maximum file size.
 '
 
 Imports System.IO
@@ -32,6 +33,13 @@ Imports System.IO
 ''' Provides encryption by key generated from a file and a key
 ''' </summary>
 Public Class FileAndKeyEncryption : Implements IDisposable
+#Region "Private constants"
+   ''' <summary>
+   ''' Maximum allowed key file size
+   ''' </summary>
+   Private Const MAX_KEY_FILE_SIZE As Long = 10_000_000L
+#End Region
+
 #Region "Instance variables"
    '******************************************************************
    ' Instance variables
@@ -41,6 +49,11 @@ Public Class FileAndKeyEncryption : Implements IDisposable
    ''' Instance of <see cref="SplitKeyEncryption"/> to use behind this interface.
    ''' </summary>
    Private ReadOnly m_SplitKeyEncryption As SplitKeyEncryption
+
+   ''' <summary>
+   ''' Object only used for locking the call to Dispose.
+   ''' </summary>
+   Private ReadOnly m_LockObject As New Object
 #End Region
 
 #Region "Constructors"
@@ -53,11 +66,11 @@ Public Class FileAndKeyEncryption : Implements IDisposable
    ''' </summary>
    ''' <param name="hmacKey">Key for the HMAC of the file.</param>
    ''' <param name="keyFilePath">Path of key file.</param>
-   ''' <exception cref="ArgumentException">Thrown if <paramref name="keyFilePath"/> contains invalid characters.</exception>
+   ''' <exception cref="ArgumentException">Thrown if <paramref name="keyFilePath"/> contains invalid characters or the contents are too large.</exception>
    ''' <exception cref="ArgumentNullException">Thrown if any parameter is <c>Nothing</c>.</exception>
    ''' <exception cref="DirectoryNotFoundException">Thrown if the directory in <paramref name="keyFilePath"/> does not exist.</exception>
    ''' <exception cref="FileNotFoundException">Thrown if <paramref name="keyFilePath"/> is not found.</exception>
-   ''' <exception cref="IOException">Thrown if an I/O error occurs during access to the file.</exception>
+   ''' <exception cref="IOException">Thrown if an I/O error occurs during accessing the file.</exception>
    ''' <exception cref="NotSupportedException">Thrown if <paramref name="keyFilePath"/> is in an invalid format.</exception>
    ''' <exception cref="PathTooLongException">Thrown if <paramref name="keyFilePath"/> is too long.</exception>
    ''' <exception cref="UnauthorizedAccessException">Thrown if <paramref name="keyFilePath"/> specifies a directory or the caller
@@ -224,12 +237,23 @@ Public Class FileAndKeyEncryption : Implements IDisposable
 #End Region
 
 #Region "File helper methods"
+   ''' <summary>
+   ''' Get the length of a file.
+   ''' </summary>
+   ''' <param name="aFilePath">Path to the file.</param>
+   ''' <returns>Length of the file.</returns>
+   Private Shared Function GetFileSize(aFilePath As String) As Long
+      Dim fi As New FileInfo(aFilePath)
+
+      Return fi.Length
+   End Function
+
    ''' <summary>
    ''' Get the content of the key file.
    ''' </summary>
    ''' <param name="keyFilePath">Key file to be used.</param>
    ''' <returns>Content of the key file.</returns>
-   ''' <exception cref="ArgumentException">Thrown if <paramref name="keyFilePath"/> contains invalid characters.</exception>
+   ''' <exception cref="ArgumentException">Thrown if <paramref name="keyFilePath"/> contains invalid characters or the file contents are too large.</exception>
    ''' <exception cref="DirectoryNotFoundException">Thrown if the directory in <paramref name="keyFilePath"/> does not exist.</exception>
    ''' <exception cref="FileNotFoundException">Thrown if <paramref name="keyFilePath"/> is not found.</exception>
    ''' <exception cref="IOException">Thrown if an I/O error occurs during access to the file.</exception>
@@ -241,9 +265,13 @@ Public Class FileAndKeyEncryption : Implements IDisposable
       Dim result As Byte()
 
       If File.Exists(keyFilePath) Then
-         result = File.ReadAllBytes(keyFilePath)
+         If GetFileSize(keyFilePath) <= MAX_KEY_FILE_SIZE Then
+            result = File.ReadAllBytes(keyFilePath)
+         Else
+            Throw New ArgumentException($"Key file is too large (maximum is {MAX_KEY_FILE_SIZE:#,##0} bytes)")
+         End If
       Else
-         Throw New FileNotFoundException("File '" & keyFilePath & "' does not exist")
+         Throw New FileNotFoundException("Key file does not exist", keyFilePath)
       End If
 
       Return result
@@ -282,7 +310,7 @@ Public Class FileAndKeyEncryption : Implements IDisposable
             '
             ' Disposing of resources needs to be synchronized to prevent a race condition.
             '
-            SyncLock m_SplitKeyEncryption
+            SyncLock m_LockObject
                m_SplitKeyEncryption.Dispose()
             End SyncLock
          End If
@@ -317,7 +345,9 @@ Public Class FileAndKeyEncryption : Implements IDisposable
    ''' <returns><c>true</c>, if this instance is in a valid state, <c>false</c>, if this instance has already been disposed of.</returns>
    Public ReadOnly Property IsValid As Boolean
       Get
-         Return Not m_IsDisposed
+         SyncLock m_LockObject
+            Return Not m_IsDisposed
+         End SyncLock
       End Get
    End Property
 #End Region

TUPWLib/Crypto/ProtectedByteArray.vb

@@ -18,12 +18,13 @@
 '
 ' Author: Frank Schwab, DB Systel GmbH
 '
-' Version: 2.0.1
+' Version: 2.0.2
 '
 ' Change history:
 '    2020-04-23: V1.0.0: Created.
 '    2020-12-10: V2.0.0: Throw ObjectDisposedException instead of InvalidOperationException.
 '    2020-12-11: V2.0.1: Put IsValid method where it belongs.
+'    2020-12-16: V2.0.2: Made usage of SyncLock for disposal consistent.
 '
 
 ''' <summary>
@@ -44,6 +45,11 @@ Public Class ProtectedByteArray : Implements IDisposable
 
    Private m_ProtectedArray As ShuffledByteArray
    Private m_Obfuscation As ShuffledByteArray
+
+   ''' <summary>
+   ''' Object only used for locking the call to Dispose.
+   ''' </summary>
+   Private ReadOnly m_LockObject As New Object
 #End Region
 
 #Region "Constructors"
@@ -285,13 +291,16 @@ Public Class ProtectedByteArray : Implements IDisposable
       '
       ' Disposing of resources needs to be synchronized to prevent a race condition.
       '
-      SyncLock m_ProtectedArray
+      SyncLock m_LockObject
          If Not m_IsDisposed Then
             m_IsDisposed = True
 
             If disposeManagedResources Then
                m_ProtectedArray.Dispose()
                m_Obfuscation.Dispose()
+
+               m_ProtectedArray = Nothing
+               m_Obfuscation = Nothing
             End If
 
             ' Free unmanaged resources (unmanaged objects) and override Finalize() below.
@@ -325,7 +334,9 @@ Public Class ProtectedByteArray : Implements IDisposable
    ''' <returns><c>True</c>, if this instance has not been disposed of, <c>false</c> otherwise.</returns>
    Public ReadOnly Property IsValid() As Boolean
       Get
-         Return m_ProtectedArray.IsValid
+         SyncLock m_LockObject
+            Return Not m_IsDisposed
+         End SyncLock
       End Get
    End Property
 #End Region

TUPWLib/Crypto/ShuffledByteArray.vb

@@ -18,7 +18,7 @@
 '
 ' Author: Frank Schwab, DB Systel GmbH
 '
-' Version: 2.0.2
+' Version: 2.0.3
 '
 ' Change history:
 '    2020-04-23: V1.0.0: Created.
@@ -28,6 +28,7 @@
 '    2020-12-10: V2.0.0: Throw ObjectDisposedException instead of InvalidOperationException.
 '    2020-12-11: V2.0.1: Put IsValid method where it belongs.
 '    2020-12-14: V2.0.2: Corrected some comments.
+'    2020-12-16: V2.0.3: Made usage of SyncLock for disposal consistent.
 '
 
 ''' <summary>
@@ -459,6 +460,9 @@ Public Class ShuffledByteArray : Implements IDisposable
       m_HashCode = 0
 
       m_StoredArrayLength = 0
+
+      m_ByteArray = Nothing
+      m_IndexArray = Nothing
    End Sub
 #End Region
 
@@ -606,7 +610,9 @@ Public Class ShuffledByteArray : Implements IDisposable
    ''' <returns><c>true</c>, if this instance is in a valid state, <c>false</c>, if this instance has already been disposed of.</returns>
    Public ReadOnly Property IsValid As Boolean
       Get
-         Return Not m_IsDisposed
+         SyncLock m_LockObject
+            Return Not m_IsDisposed
+         End SyncLock
       End Get
    End Property
 #End Region

TUPWLib/Crypto/SplitKeyEncryption.vb

@@ -18,7 +18,7 @@
 '
 ' Author: Frank Schwab, DB Systel GmbH
 '
-' Version: 2.0.1
+' Version: 2.0.2
 '
 ' Change history:
 '    2020-05-05: V1.0.0: Created.
@@ -34,6 +34,7 @@
 '    2020-12-10: V1.3.1: Made hashing simpler and 2.5 times faster.
 '    2020-12-10: V2.0.0: Correct handling of disposed instances.
 '    2020-12-11: V2.0.1: Put IsValid method where it belongs.
+'    2020-12-16: V2.0.2: Made usage of SyncLock for disposal consistent and changed some message creations.
 '
 
 Imports System.IO
@@ -89,7 +90,7 @@ Public Class SplitKeyEncryption : Implements IDisposable
    ''' <summary>
    ''' Maximum length for source bytes.
    ''' </summary>
-   Private Const MAXIMUM_SOURCE_BYTES_LENGTH As UInteger = 10000000
+   Private Const MAXIMUM_SOURCE_BYTES_LENGTH As UInteger = 10_000_000
 
    ''' <summary>
    ''' Minimum entropy for source bytes.
@@ -209,6 +210,11 @@ Public Class SplitKeyEncryption : Implements IDisposable
    ''' HMAC key to use.
    ''' </summary>
    Private m_HMACKey As ProtectedByteArray
+
+   ''' <summary>
+   ''' Object only used for locking the call to Dispose.
+   ''' </summary>
+   Private ReadOnly m_LockObject As New Object
 #End Region
 
 #Region "Constructors"
@@ -449,10 +455,10 @@ Public Class SplitKeyEncryption : Implements IDisposable
       RequireNonNull(aHMACKey, NameOf(aHMACKey))
 
       If aHMACKey.Length < MINIMUM_HMAC_KEY_LENGTH Then _
-         Throw New ArgumentException("HMAC key length is less than " & MINIMUM_HMAC_KEY_LENGTH.ToString())
+         Throw New ArgumentException($"HMAC key length is less than {MINIMUM_HMAC_KEY_LENGTH}")
 
       If aHMACKey.Length > MAXIMUM_HMAC_KEY_LENGTH Then _
-         Throw New ArgumentException("HMAC key length is larger than " & MAXIMUM_HMAC_KEY_LENGTH.ToString())
+         Throw New ArgumentException($"HMAC key length is larger than {MAXIMUM_HMAC_KEY_LENGTH}")
    End Sub
 
    ''' <summary>
@@ -491,10 +497,10 @@ Public Class SplitKeyEncryption : Implements IDisposable
       End If
 
       If ec.Count < MINIMUM_SOURCE_BYTES_LENGTH Then _
-         Throw New ArgumentException("There are less than " & MINIMUM_SOURCE_BYTES_LENGTH.ToString() & " source bytes")
+         Throw New ArgumentException($"There are less than {MINIMUM_SOURCE_BYTES_LENGTH} source bytes")
 
       If ec.Count > MAXIMUM_SOURCE_BYTES_LENGTH Then _
-         Throw New ArgumentException("There are more than " & MAXIMUM_SOURCE_BYTES_LENGTH.ToString() & " source bytes")
+         Throw New ArgumentException($"There are more than {MAXIMUM_SOURCE_BYTES_LENGTH:#,##0} source bytes")
    End Sub
 #End Region
 
@@ -1201,9 +1207,12 @@ Public Class SplitKeyEncryption : Implements IDisposable
             '
             ' Disposing of resources needs to be synchronized to prevent a race condition.
             '
-            SyncLock m_EncryptionKey
+            SyncLock m_LockObject
                m_EncryptionKey.Dispose()
                m_HMACKey.Dispose()
+
+               m_EncryptionKey = Nothing
+               m_HMACKey = Nothing
             End SyncLock
          End If
 
@@ -1237,7 +1246,9 @@ Public Class SplitKeyEncryption : Implements IDisposable
    ''' <returns><c>true</c>, if this instance is in a valid state, <c>false</c>, if this instance has already been disposed of.</returns>
    Public ReadOnly Property IsValid As Boolean
       Get
-         Return Not m_IsDisposed
+         SyncLock m_LockObject
+            Return Not m_IsDisposed
+         End SyncLock
       End Get
    End Property
 #End Region