AppStd/Modules
8
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

jj: FileContainer Version 0.0.2

Browse Source
This commit is contained in:
Jonathan Jenne
2018-11-21 17:03:05 +01:00
parent 0f105b6ebf
commit 7b2ae3abc3
6 changed files with 190 additions and 241 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
Filesystem/Encryption.vb
View File

@@ -8,12 +8,19 @@ Imports DigitalData.Modules.Logging
Friend Class Encryption
' This constant is used to determine the keysize of the encryption algorithm in bits.
' We divide this by 8 within the code below to get the equivalent number of bytes.
Private Const KEYSIZE As Integer = 256
Private Const KEY_SIZE As Integer = 256
' This constant determines the number of iterations for the password bytes generation function.
Private Const DERIVATION_ITERATIONS As Integer = 1000
Private Const BLOCK_SIZE As Integer = 256
Private _paddingMode As PaddingMode = PaddingMode.Zeros
Private _cipherMode As CipherMode = CipherMode.CBC
Private ReadOnly _password As String
Private _logger As Logger
Public Sub New(LogConfig As LogConfig, Password As String)
_logger = LogConfig.GetLogger()
@@ -37,11 +44,12 @@ Friend Class Encryption
Dim oSaltStringBytes = Generate256BitsOfRandomEntropy()
Dim oIvStringBytes = Generate256BitsOfRandomEntropy()
Using oPassword = New Rfc2898DeriveBytes(_password, oSaltStringBytes, DERIVATION_ITERATIONS)
Dim oKeyBytes = oPassword.GetBytes(KEYSIZE / 8)
Dim oKeyBytes = oPassword.GetBytes(KEY_SIZE / 8)
Using oSymmetricKey = New RijndaelManaged()
oSymmetricKey.BlockSize = 256
oSymmetricKey.Mode = CipherMode.CBC
oSymmetricKey.Padding = PaddingMode.PKCS7
oSymmetricKey.BlockSize = BLOCK_SIZE
oSymmetricKey.Mode = _cipherMode
oSymmetricKey.Padding = _paddingMode
Using oEncryptor = oSymmetricKey.CreateEncryptor(oKeyBytes, oIvStringBytes)
Using oMemoryStream = New MemoryStream()
Using oCryptoStream = New CryptoStream(oMemoryStream, oEncryptor, CryptoStreamMode.Write)
@@ -76,18 +84,18 @@ Friend Class Encryption
' Get the complete stream of bytes that represent:
' [32 bytes of Salt] + [32 bytes of IV] + [n bytes of CipherText]
' Get the saltbytes by extracting the first 32 bytes from the supplied cipherText bytes.
Dim oSaltStringBytes = cipherTextBytesWithSaltAndIv.Take(KEYSIZE / 8).ToArray()
Dim oSaltStringBytes = cipherTextBytesWithSaltAndIv.Take(KEY_SIZE / 8).ToArray()
' Get the IV bytes by extracting the next 32 bytes from the supplied cipherText bytes.
Dim oIvStringBytes = cipherTextBytesWithSaltAndIv.Skip(KEYSIZE / 8).Take(KEYSIZE / 8).ToArray()
Dim oIvStringBytes = cipherTextBytesWithSaltAndIv.Skip(KEY_SIZE / 8).Take(KEY_SIZE / 8).ToArray()
' Get the actual cipher text bytes by removing the first 64 bytes from the cipherText string.
Dim oCipherTextBytes = cipherTextBytesWithSaltAndIv.Skip((KEYSIZE / 8) * 2).Take(cipherTextBytesWithSaltAndIv.Length - ((KEYSIZE / 8) * 2)).ToArray()
Dim oCipherTextBytes = cipherTextBytesWithSaltAndIv.Skip((KEY_SIZE / 8) * 2).Take(cipherTextBytesWithSaltAndIv.Length - ((KEY_SIZE / 8) * 2)).ToArray()
Using oPassword = New Rfc2898DeriveBytes(_password, oSaltStringBytes, DERIVATION_ITERATIONS)
Dim oKeyBytes = oPassword.GetBytes(KEYSIZE / 8)
Dim oKeyBytes = oPassword.GetBytes(KEY_SIZE / 8)
Using oSymmetricKey = New RijndaelManaged()
oSymmetricKey.BlockSize = 256
oSymmetricKey.Mode = CipherMode.CBC
oSymmetricKey.Padding = PaddingMode.PKCS7
oSymmetricKey.BlockSize = BLOCK_SIZE
oSymmetricKey.Mode = _cipherMode
oSymmetricKey.Padding = _paddingMode
Using oDecryptor = oSymmetricKey.CreateDecryptor(oKeyBytes, oIvStringBytes)
Using oMemoryStream = New MemoryStream(oCipherTextBytes)
Using oCryptoStream = New CryptoStream(oMemoryStream, oDecryptor, CryptoStreamMode.Read)