Datatable Column ByteArray Problem

  • Thread starter Thread starter Phil C.
  • Start date Start date
P

Phil C.

I've been having trouble getting a byte array back as a datatable column
with this code:
Public Class RegisteredCustomerVerify
''' -----------------------------------------------------------------------------
''' <summary>
''' Friend Function ValidEmail
''' Pass plaintext email address to stored proc that must use
''' aes key and decrypt each row of customer table and compare the
''' email address to the passed email
''' </summary>
''' <param name="plaintextEmailAddress"></param>
''' <returns>Returns True (email match) or False (no Email
match)</returns>
''' <remarks>
''' </remarks>
''' <history>
''' [SmallFry] 9/17/2005 Created
''' </history>
''' -----------------------------------------------------------------------------
Friend Function IfRegistered(ByVal plaintextEmailAddress As String,
ByVal pass As String) As Boolean
Dim custDs As New DataSet
'custDs = SqlHelper.ExecuteDataset(connectionString(),
CommandType.StoredProcedure, "GetCustomerTable")
Dim cn As New SqlConnection(connectionString())
Dim cmd As New SqlDataAdapter
cmd.SelectCommand = New SqlCommand
With cmd.SelectCommand
.Connection = cn
.CommandText = "GetCustomerTable"
.CommandType = CommandType.StoredProcedure
End With
cmd.Fill(custDs, "Customers")
Dim dRow As DataRow
Dim dCol As DataColumn
Dim aes As New AesCryptClass
Dim iVByteArray As Byte()
Dim emailAddressByteArray() As Byte
Dim decryptedEmailAddress As String
Dim passByteArray() As Byte
Dim saltHsh As New SaltedHash
For Each dRow In custDs.Tables.Item(0).Rows
'Get the IV value and the encrypted email value of each row
If Not (dRow("IV").Equals(System.DBNull.Value) And
dRow("EmailAddress").Equals(System.DBNull.Value)) Then

'Dim ivSqlBinary As New SqlBinary(dRow("IV"))
Dim type As Type = dRow.Table.Columns("IV").DataType()
type.ToString()
iVByteArray = dRow("IV")
emailAddressByteArray =
Encoding.UTF8.GetBytes(dRow("EmailAddress"))
passByteArray = Encoding.UTF8.GetBytes(dRow("Password"))
decryptedEmailAddress = aes.Decrypt(emailAddressByteArray,
iVByteArray)
If plaintextEmailAddress = decryptedEmailAddress And _
saltHsh.ComparePasswords(passByteArray,
Encoding.UTF8.GetBytes(pass)) Then
Return True
End If
End If
Next
Return False
End Function


In the debugger (code in asterisked section below), I am getting the table
"item" as <cannot view indexed property>
which led me to read this article:
http://dotnet247.com/247reference/msgs/17/86113.aspx
which states:

Mark Miller
There's a subtle problem with your code. The Rows property of a
DataTable
returns a DataRowCollection, not a DataRow. The indexer you are
attempting
to use ([0, DataRowVersion.Current]) only exists in DataRow. Further
this
indexer returns an object, as in row["columnName"] (ie. a column
value), not
a DataRow.

The only indexer in DataRowCollection is DataRow this[int index]
{get;}.

So, the correct way to write your code would be:

string fieldValue = updateDataSet.Tables[0].Rows[0][0,
DataRowVersion.Current];

This will return the current version of the value in the first column,
in
the first row, of the first table.

--

---Mark



but I think I am doing it correctly.

Any ideas would be appreciated.


Below is the expanded tree from my debugger window on the datatable:

******************************************************************
- custDs {System.Data.DataSet} System.Data.DataSet
CaseSensitive False Boolean
Container Nothing System.ComponentModel.IContainer
DataSetName "NewDataSet" String
+ DefaultViewManager {System.Data.DataViewManager}
System.Data.DataViewManager
DesignMode False Boolean
EnforceConstraints True Boolean
+ ExtendedProperties {System.Data.PropertyCollection}
System.Data.PropertyCollection
HasErrors False Boolean
+ Locale {System.Globalization.CultureInfo}
System.Globalization.CultureInfo
Namespace "" String
Prefix "" String
+ Relations
{System.Data.DataRelationCollection.DataSetRelationCollection}
System.Data.DataRelationCollection
Site Nothing System.ComponentModel.ISite
- Tables {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
+ [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
<cannot view indexed property> Expression expected.
+ custDs.Tables {System.Data.DataTableCollection}
System.Data.DataTableCollection
*********************************************************************************************
 
Phil,

I hate decrypting problems, however I have the idea that you at least miss
the streaming, for which you can use to avoid a disk the memorystream.

http://msdn2.microsoft.com/en-us/library/system.io.memorystream.aspx

I answered it because I saw no answers so don't expect much help from this
beside this.

Cor


Phil C. said:
I've been having trouble getting a byte array back as a datatable column
with this code:
Public Class RegisteredCustomerVerify
''' -----------------------------------------------------------------------------
''' <summary>
''' Friend Function ValidEmail
''' Pass plaintext email address to stored proc that must use
''' aes key and decrypt each row of customer table and compare the
''' email address to the passed email
''' </summary>
''' <param name="plaintextEmailAddress"></param>
''' <returns>Returns True (email match) or False (no Email
match)</returns>
''' <remarks>
''' </remarks>
''' <history>
''' [SmallFry] 9/17/2005 Created
''' </history>
''' -----------------------------------------------------------------------------
Friend Function IfRegistered(ByVal plaintextEmailAddress As String,
ByVal pass As String) As Boolean
Dim custDs As New DataSet
'custDs = SqlHelper.ExecuteDataset(connectionString(),
CommandType.StoredProcedure, "GetCustomerTable")
Dim cn As New SqlConnection(connectionString())
Dim cmd As New SqlDataAdapter
cmd.SelectCommand = New SqlCommand
With cmd.SelectCommand
.Connection = cn
.CommandText = "GetCustomerTable"
.CommandType = CommandType.StoredProcedure
End With
cmd.Fill(custDs, "Customers")
Dim dRow As DataRow
Dim dCol As DataColumn
Dim aes As New AesCryptClass
Dim iVByteArray As Byte()
Dim emailAddressByteArray() As Byte
Dim decryptedEmailAddress As String
Dim passByteArray() As Byte
Dim saltHsh As New SaltedHash
For Each dRow In custDs.Tables.Item(0).Rows
'Get the IV value and the encrypted email value of each row
If Not (dRow("IV").Equals(System.DBNull.Value) And
dRow("EmailAddress").Equals(System.DBNull.Value)) Then

'Dim ivSqlBinary As New SqlBinary(dRow("IV"))
Dim type As Type = dRow.Table.Columns("IV").DataType()
type.ToString()
iVByteArray = dRow("IV")
emailAddressByteArray =
Encoding.UTF8.GetBytes(dRow("EmailAddress"))
passByteArray = Encoding.UTF8.GetBytes(dRow("Password"))
decryptedEmailAddress = aes.Decrypt(emailAddressByteArray,
iVByteArray)
If plaintextEmailAddress = decryptedEmailAddress And _
saltHsh.ComparePasswords(passByteArray,
Encoding.UTF8.GetBytes(pass)) Then
Return True
End If
End If
Next
Return False
End Function


In the debugger (code in asterisked section below), I am getting the table
"item" as <cannot view indexed property>
which led me to read this article:
http://dotnet247.com/247reference/msgs/17/86113.aspx
which states:

Mark Miller
There's a subtle problem with your code. The Rows property of a
DataTable
returns a DataRowCollection, not a DataRow. The indexer you are
attempting
to use ([0, DataRowVersion.Current]) only exists in DataRow. Further
this
indexer returns an object, as in row["columnName"] (ie. a column
value), not
a DataRow.

The only indexer in DataRowCollection is DataRow this[int index]
{get;}.

So, the correct way to write your code would be:

string fieldValue = updateDataSet.Tables[0].Rows[0][0,
DataRowVersion.Current];

This will return the current version of the value in the first
column, in
the first row, of the first table.

--

---Mark



but I think I am doing it correctly.

Any ideas would be appreciated.


Below is the expanded tree from my debugger window on the datatable:

******************************************************************
- custDs {System.Data.DataSet} System.Data.DataSet
CaseSensitive False Boolean
Container Nothing System.ComponentModel.IContainer
DataSetName "NewDataSet" String
+ DefaultViewManager {System.Data.DataViewManager}
System.Data.DataViewManager
DesignMode False Boolean
EnforceConstraints True Boolean
+ ExtendedProperties {System.Data.PropertyCollection}
System.Data.PropertyCollection
HasErrors False Boolean
+ Locale {System.Globalization.CultureInfo}
System.Globalization.CultureInfo
Namespace "" String
Prefix "" String
+ Relations
{System.Data.DataRelationCollection.DataSetRelationCollection}
System.Data.DataRelationCollection
Site Nothing System.ComponentModel.ISite
- Tables {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection]
{System.Data.DataTableCollection} System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection]
{System.Data.DataTableCollection} System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection]
{System.Data.DataTableCollection} System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection]
{System.Data.DataTableCollection} System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection]
{System.Data.DataTableCollection} System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
+ [System.Data.DataTableCollection]
{System.Data.DataTableCollection} System.Data.DataTableCollection
<cannot view indexed property> Expression expected.
+ custDs.Tables {System.Data.DataTableCollection}
System.Data.DataTableCollection
*********************************************************************************************
Click to expand...
 
Cor,

There is no problem with decryption,
the decryption code works fine independently, and indeed does use memory
streams.

'--------------------------Function Encrypt---------------------------

Friend Overloads Function Encrypt(ByVal plainText As String) As Byte()

'Declare a UTF8Encoding object so that we can use the GetByte

'method to transform the plain Text into a Byte Array

'Dim utf8encoder As New UTF8Encoding

Dim inputInBytes() As Byte = Encoding.UTF8.GetBytes(plainText)

'Create a new AES Service Provider

Dim aesProvider As New RijndaelManaged

'Declare the key size

aesProvider.KeySize = 256

aesProvider.BlockSize = 256

'Set the aes key

aesProvider.Key() = _key





'----------Generate a new IV each time the encrypt function is called:



aesProvider.GenerateIV()

_encryptInitVector = aesProvider.IV



'The ICryptTransform interface uses the Aes crypt provider along with

'encryption key and initialization vector info

'Generate an ICryptoTransform object with the provider create encryptor

Dim cryptoTransform As ICryptoTransform = aesProvider.CreateEncryptor()

' Crypto functions need a stream to output the encrypted info.

'We want to use a memory stream

Dim encryptedStream As New MemoryStream

Dim cryptStream As New CryptoStream(encryptedStream, cryptoTransform,
CryptoStreamMode.Write)

'Write the encrypted information to he stream. Flush the information

'When done to ensure everything is out of the buffer.

cryptStream.Write(inputInBytes, 0, inputInBytes.Length)

cryptStream.FlushFinalBlock()

encryptedStream.Position = 0

'Read the stream back into a byte array and return it

Dim result(encryptedStream.Length - 1) As Byte

encryptedStream.Read(result, 0, encryptedStream.Length)

cryptStream.Close()

Return result

End Function





Friend Overloads Function Encrypt(ByVal plainText As String, ByVal iV As
Byte()) As Byte()

'Declare a UTF8Encoding object so that we can use the GetByte

'method to transform the plain Text into a Byte Array

'Dim utf8encoder As New UTF8Encoding

Dim inputInBytes() As Byte = Encoding.UTF8.GetBytes(plainText)

'Create a new AES Service Provider

Dim aesProvider As New RijndaelManaged

'Declare the key size

aesProvider.KeySize = 256

aesProvider.BlockSize = 256

'Get the aes key from the config handler



'Set the aes key

aesProvider.Key() = _key





'Use the iv Passed in as a parameter



_encryptInitVector = iV





'The ICryptTransform interface uses the Aes crypt provider along with

'encryption key and initialization vector info

'Generate an ICryptoTransform object with the provider create encryptor

Dim cryptoTransform As ICryptoTransform = aesProvider.CreateEncryptor()

' Crypto functions need a stream to output the encrypted info.

'We want to use a memory stream

Dim encryptedStream As New MemoryStream

Dim cryptStream As New CryptoStream(encryptedStream, cryptoTransform,
CryptoStreamMode.Write)

'Write the encrypted information to he stream. Flush the information

'When done to ensure everything is out of the buffer.

cryptStream.Write(inputInBytes, 0, inputInBytes.Length)

cryptStream.FlushFinalBlock()

encryptedStream.Position = 0

'Read the stream back into a byte array and return it

Dim result(encryptedStream.Length - 1) As Byte

encryptedStream.Read(result, 0, encryptedStream.Length)

cryptStream.Close()

Return result

End Function

'---------------------------End Function Encrypt

'----------------------------Function Decrypt

Friend Function Decrypt(ByVal inputInBytes() As Byte, ByVal iVInBytes() As
Byte) As String

'UTFEncoding is used to transform the decrypted Byte Array

'information back into a string.

'Dim utf8encoder As New UTF8Encoding

Dim aesProvider As New RijndaelManaged

'Declare the key size and block size

aesProvider.KeySize = 256

aesProvider.BlockSize = 256

'Get the Aes Key

Dim aesKeyBytes() As Byte = _key

'Get the crypto transform object from the provider given the

'key and iv vector

Dim cryptoTransform As ICryptoTransform =
aesProvider.CreateDecryptor(aesKeyBytes, iVInBytes)

'Provide memory stream

Dim decryptedStream As New MemoryStream

Dim cryptStream As New CryptoStream(decryptedStream, cryptoTransform,
CryptoStreamMode.Write)

cryptStream.Write(inputInBytes, 0, inputInBytes.Length)

cryptStream.FlushFinalBlock()

decryptedStream.Position = 0

'Read the memory stream and convert it back to a string

Dim result(decryptedStream.Length - 1) As Byte

decryptedStream.Read(result, 0, decryptedStream.Length)

cryptStream.Close()

'Dim myUTF As New UTF8Encoding

Return Encoding.UTF8.GetString(result)

End Function

End Class

Cor Ligthert said:
Phil,

I hate decrypting problems, however I have the idea that you at least miss
the streaming, for which you can use to avoid a disk the memorystream.

http://msdn2.microsoft.com/en-us/library/system.io.memorystream.aspx

I answered it because I saw no answers so don't expect much help from this
beside this.

Cor


Phil C. said:
I've been having trouble getting a byte array back as a datatable column
with this code:
Public Class RegisteredCustomerVerify
''' -----------------------------------------------------------------------------
''' <summary>
''' Friend Function ValidEmail
''' Pass plaintext email address to stored proc that must use
''' aes key and decrypt each row of customer table and compare the
''' email address to the passed email
''' </summary>
''' <param name="plaintextEmailAddress"></param>
''' <returns>Returns True (email match) or False (no Email
match)</returns>
''' <remarks>
''' </remarks>
''' <history>
''' [SmallFry] 9/17/2005 Created
''' </history>
''' -----------------------------------------------------------------------------
Friend Function IfRegistered(ByVal plaintextEmailAddress As String,
ByVal pass As String) As Boolean
Dim custDs As New DataSet
'custDs = SqlHelper.ExecuteDataset(connectionString(),
CommandType.StoredProcedure, "GetCustomerTable")
Dim cn As New SqlConnection(connectionString())
Dim cmd As New SqlDataAdapter
cmd.SelectCommand = New SqlCommand
With cmd.SelectCommand
.Connection = cn
.CommandText = "GetCustomerTable"
.CommandType = CommandType.StoredProcedure
End With
cmd.Fill(custDs, "Customers")
Dim dRow As DataRow
Dim dCol As DataColumn
Dim aes As New AesCryptClass
Dim iVByteArray As Byte()
Dim emailAddressByteArray() As Byte
Dim decryptedEmailAddress As String
Dim passByteArray() As Byte
Dim saltHsh As New SaltedHash
For Each dRow In custDs.Tables.Item(0).Rows
'Get the IV value and the encrypted email value of each row
If Not (dRow("IV").Equals(System.DBNull.Value) And
dRow("EmailAddress").Equals(System.DBNull.Value)) Then

'Dim ivSqlBinary As New SqlBinary(dRow("IV"))
Dim type As Type = dRow.Table.Columns("IV").DataType()
type.ToString()
iVByteArray = dRow("IV")
emailAddressByteArray =
Encoding.UTF8.GetBytes(dRow("EmailAddress"))
passByteArray = Encoding.UTF8.GetBytes(dRow("Password"))
decryptedEmailAddress = aes.Decrypt(emailAddressByteArray,
iVByteArray)
If plaintextEmailAddress = decryptedEmailAddress And _
saltHsh.ComparePasswords(passByteArray,
Encoding.UTF8.GetBytes(pass)) Then
Return True
End If
End If
Next
Return False
End Function


In the debugger (code in asterisked section below), I am getting the
table "item" as <cannot view indexed property>
which led me to read this article:
http://dotnet247.com/247reference/msgs/17/86113.aspx
which states:

Mark Miller
There's a subtle problem with your code. The Rows property of a
DataTable
returns a DataRowCollection, not a DataRow. The indexer you are
attempting
to use ([0, DataRowVersion.Current]) only exists in DataRow. Further
this
indexer returns an object, as in row["columnName"] (ie. a column
value), not
a DataRow.

The only indexer in DataRowCollection is DataRow this[int index]
{get;}.

So, the correct way to write your code would be:

string fieldValue = updateDataSet.Tables[0].Rows[0][0,
DataRowVersion.Current];

This will return the current version of the value in the first
column, in
the first row, of the first table.

--

---Mark



but I think I am doing it correctly.

Any ideas would be appreciated.


Below is the expanded tree from my debugger window on the datatable:

******************************************************************
- custDs {System.Data.DataSet} System.Data.DataSet
CaseSensitive False Boolean
Container Nothing System.ComponentModel.IContainer
DataSetName "NewDataSet" String
+ DefaultViewManager {System.Data.DataViewManager}
System.Data.DataViewManager
DesignMode False Boolean
EnforceConstraints True Boolean
+ ExtendedProperties {System.Data.PropertyCollection}
System.Data.PropertyCollection
HasErrors False Boolean
+ Locale {System.Globalization.CultureInfo}
System.Globalization.CultureInfo
Namespace "" String
Prefix "" String
+ Relations
{System.Data.DataRelationCollection.DataSetRelationCollection}
System.Data.DataRelationCollection
Site Nothing System.ComponentModel.ISite
- Tables {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
- [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
Count 1 Integer
IsReadOnly False Boolean
IsSynchronized False Boolean
Item <cannot view indexed property> System.Data.DataTable
- SyncRoot {System.Data.DataTableCollection} Object
+ [System.Data.DataTableCollection] {System.Data.DataTableCollection}
System.Data.DataTableCollection
<cannot view indexed property> Expression expected.
+ custDs.Tables {System.Data.DataTableCollection}
System.Data.DataTableCollection
*********************************************************************************************
Click to expand...
Click to expand...
 
Cor,

There is no problem with decryption. The encryption/decryption classes
do use memory streams and work just fine.

'--------------------------Function Encrypt---------------------------

Friend Overloads Function Encrypt(ByVal plainText As String) As Byte()

'Declare a UTF8Encoding object so that we can use the GetByte

'method to transform the plain Text into a Byte Array

'Dim utf8encoder As New UTF8Encoding

Dim inputInBytes() As Byte = Encoding.UTF8.GetBytes(plainText)

'Create a new AES Service Provider

Dim aesProvider As New RijndaelManaged

'Declare the key size

aesProvider.KeySize = 256

aesProvider.BlockSize = 256

'Set the aes key

aesProvider.Key() = _key





'----------Generate a new IV each time the encrypt function is called:



aesProvider.GenerateIV()

_encryptInitVector = aesProvider.IV



'The ICryptTransform interface uses the Aes crypt provider along with

'encryption key and initialization vector info

'Generate an ICryptoTransform object with the provider create encryptor

Dim cryptoTransform As ICryptoTransform = aesProvider.CreateEncryptor()

' Crypto functions need a stream to output the encrypted info.

'We want to use a memory stream

Dim encryptedStream As New MemoryStream

Dim cryptStream As New CryptoStream(encryptedStream, cryptoTransform,
CryptoStreamMode.Write)

'Write the encrypted information to he stream. Flush the information

'When done to ensure everything is out of the buffer.

cryptStream.Write(inputInBytes, 0, inputInBytes.Length)

cryptStream.FlushFinalBlock()

encryptedStream.Position = 0

'Read the stream back into a byte array and return it

Dim result(encryptedStream.Length - 1) As Byte

encryptedStream.Read(result, 0, encryptedStream.Length)

cryptStream.Close()

Return result

End Function





Friend Overloads Function Encrypt(ByVal plainText As String, ByVal iV As
Byte()) As Byte()

'Declare a UTF8Encoding object so that we can use the GetByte

'method to transform the plain Text into a Byte Array

'Dim utf8encoder As New UTF8Encoding

Dim inputInBytes() As Byte = Encoding.UTF8.GetBytes(plainText)

'Create a new AES Service Provider

Dim aesProvider As New RijndaelManaged

'Declare the key size

aesProvider.KeySize = 256

aesProvider.BlockSize = 256

'Get the aes key from the config handler



'Set the aes key

aesProvider.Key() = _key





'Use the iv Passed in as a parameter



_encryptInitVector = iV





'The ICryptTransform interface uses the Aes crypt provider along with

'encryption key and initialization vector info

'Generate an ICryptoTransform object with the provider create encryptor

Dim cryptoTransform As ICryptoTransform = aesProvider.CreateEncryptor()

' Crypto functions need a stream to output the encrypted info.

'We want to use a memory stream

Dim encryptedStream As New MemoryStream

Dim cryptStream As New CryptoStream(encryptedStream, cryptoTransform,
CryptoStreamMode.Write)

'Write the encrypted information to he stream. Flush the information

'When done to ensure everything is out of the buffer.

cryptStream.Write(inputInBytes, 0, inputInBytes.Length)

cryptStream.FlushFinalBlock()

encryptedStream.Position = 0

'Read the stream back into a byte array and return it

Dim result(encryptedStream.Length - 1) As Byte

encryptedStream.Read(result, 0, encryptedStream.Length)

cryptStream.Close()

Return result

End Function

'---------------------------End Function Encrypt

'----------------------------Function Decrypt

Friend Function Decrypt(ByVal inputInBytes() As Byte, ByVal iVInBytes()
As
Byte) As String

'UTFEncoding is used to transform the decrypted Byte Array

'information back into a string.

'Dim utf8encoder As New UTF8Encoding

Dim aesProvider As New RijndaelManaged

'Declare the key size and block size

aesProvider.KeySize = 256

aesProvider.BlockSize = 256

'Get the Aes Key

Dim aesKeyBytes() As Byte = _key

'Get the crypto transform object from the provider given the

'key and iv vector

Dim cryptoTransform As ICryptoTransform =
aesProvider.CreateDecryptor(aesKeyBytes, iVInBytes)

'Provide memory stream

Dim decryptedStream As New MemoryStream

Dim cryptStream As New CryptoStream(decryptedStream, cryptoTransform,
CryptoStreamMode.Write)

cryptStream.Write(inputInBytes, 0, inputInBytes.Length)

cryptStream.FlushFinalBlock()

decryptedStream.Position = 0

'Read the memory stream and convert it back to a string

Dim result(decryptedStream.Length - 1) As Byte

decryptedStream.Read(result, 0, decryptedStream.Length)

cryptStream.Close()

'Dim myUTF As New UTF8Encoding

Return Encoding.UTF8.GetString(result)

End Function

End Class
 
Back
Top