I am building a application that can encrypt and decrypt files, in c#. The encryption seems like its working (I think its working) however the decryption gives me the exception "The input data is not a complete block." I have tried almost everything I could find online so I thought I should come here. Here is the decryption code:
static void decryptAES (/*byte[] buffer,*/string filePath,byte[] key, byte[] IV)
{
Console.WriteLine("1");
using (AesCryptoServiceProvider AES = new AesCryptoServiceProvider())
{
AES.Padding = PaddingMode.PKCS7;
AES.Key = key;
AES.BlockSize = 128;
AES.KeySize = 128;
AES.IV = IV;
using (FileStream fStream = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite))
{
using (ICryptoTransform crypt = AES.CreateDecryptor(key, IV))
{
using (CryptoStream crStream = new CryptoStream(fStream, crypt, CryptoStreamMode.Read))
{
using (StreamReader reader = new StreamReader(crStream))
{
//breaks here
string data = reader.ReadToEnd();
File.WriteAllText(filePath, data);
File.Move(filePath, filePath.Replace(".encrypted", ""));
}
}
}
}
}
}
It breaks on the line with the comment //breaks here by the way.
Thanks.
Here is the encrypt function
static void encryptAES(byte[] filesBytes,string
filePath,AesCryptoServiceProvider aes)
{
using (FileStream fStream = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite))
{
using (ICryptoTransform crypt = aes.CreateEncryptor(aes.Key, aes.IV))
{
using (CryptoStream csStream = new CryptoStream(fStream, crypt, CryptoStreamMode.Write))
{
csStream.Write(filesBytes, 0, filesBytes.Length);
}
try { File.Move(filePath, filePath + ".encrypted"); }
catch (UnauthorizedAccessException)
{
}
}
}
}
And here is the key generation:
static AesCryptoServiceProvider generateAES()
{
AesCryptoServiceProvider a = new AesCryptoServiceProvider();
a.Padding = PaddingMode.PKCS7;
a.BlockSize =128;
a.KeySize = 128;
a.GenerateIV();
a.GenerateKey();
return a;
}
Here is how I stored the IV and AES Key:
private static void dumpKeys(AesCryptoServiceProvider aes)
{
foreach (byte b in aes.Key)
{
Console.Write(b);
}
Console.WriteLine();
foreach (byte b in aes.IV)
{
Console.Write(b);
}
byte[] encryptedKey = encryptRSA(aes.Key);
byte[] encryptedIV = encryptRSA(aes.IV);
Directory.CreateDirectory(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + #"\Keys");
File.WriteAllBytes(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + #"\Keys\0000000000000.Key", encryptedKey);
File.WriteAllBytes(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + #"\Keys\1111111111111.IV", encryptedIV);
}
And here is how I retrieve the key and iv data:
byte[] AESKey = decrypt(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + #"\Keys\0000000000000.Key");
byte[] AESIV = decrypt(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + #"\Keys\1111111111111.IV");
static byte[] decrypt(string path)
{
using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider())
{
RSA.FromXmlString(Properties.Resources.privateKey);
byte[] unencrypted = RSA.Decrypt(File.ReadAllBytes(path), true);
foreach (byte b in unencrypted)
{
Console.Write(b);
}
Console.WriteLine();
return unencrypted;
}
}
Btw I store a public RSA key in my resources file and I use that to decrypt the key.
Thanks
So far, so good. Do you extract the generated Key and IV? I modified your decryption function to an encryption function...
public static void Main()
{
var f = #"q:\test.txt";
AesCryptoServiceProvider AES = new AesCryptoServiceProvider();
AES.Padding = PaddingMode.PKCS7;
AES.Mode = CipherMode.CBC;
AES.BlockSize = 128;
AES.KeySize = 128;
AES.GenerateKey();
AES.GenerateIV();
var key = AES.Key;
var iv = AES.IV;
encryptAES(AES, f, key, iv);
decryptAES(AES, f + ".encrypted", key, iv);
}
static void encryptAES(SymmetricAlgorithm algo, string filePath, byte[] key, byte[] IV)
{
using (FileStream fin = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
using (FileStream fout = new FileStream(filePath + ".encrypted", FileMode.OpenOrCreate, FileAccess.Write))
{
using (ICryptoTransform crypt = algo.CreateEncryptor(key, IV))
{
using (CryptoStream crStream = new CryptoStream(fout, crypt, CryptoStreamMode.Write))
{
fin.CopyTo(crStream);
}
}
}
}
}
static void decryptAES(SymmetricAlgorithm algo, string filePath, byte[] key, byte[] IV)
{
using (FileStream fStream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
using (ICryptoTransform crypt = algo.CreateDecryptor(key, IV))
{
using (CryptoStream crStream = new CryptoStream(fStream, crypt, CryptoStreamMode.Read))
{
using (StreamReader reader = new StreamReader(crStream))
{
string data = reader.ReadToEnd();
File.WriteAllText(filePath.Replace(".encrypted", ".restored"), data);
}
}
}
}
}
Tested it with your code, slightly modified (changed FileMode.Open to FileMode.OpenOrCreate, Added File.Delete before File.Move and merged File.WriteAllText with File.Move) and it works. So a) please review your code. b) If it still fails, provide more details, a single codeblock with every function and a Main-method that calls your functions to reproduce your failure...
static AesCryptoServiceProvider generateAES()
{
AesCryptoServiceProvider a = new AesCryptoServiceProvider();
a.Padding = PaddingMode.PKCS7;
a.BlockSize = 128;
a.KeySize = 128;
a.GenerateIV();
a.GenerateKey();
return a;
}
static void encryptAES(byte[] filesBytes, string filePath, AesCryptoServiceProvider aes)
{
using (FileStream fStream = new FileStream(filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite))
{
using (ICryptoTransform crypt = aes.CreateEncryptor(aes.Key, aes.IV))
{
using (CryptoStream csStream = new CryptoStream(fStream, crypt, CryptoStreamMode.Write))
{
csStream.Write(filesBytes, 0, filesBytes.Length);
}
try {
File.Delete(filePath + ".encrypted");
File.Move(filePath, filePath + ".encrypted");
}
catch (UnauthorizedAccessException)
{
}
}
}
}
static void decryptAES(/*byte[] buffer,*/string filePath, byte[] key, byte[] IV)
{
using (AesCryptoServiceProvider AES = new AesCryptoServiceProvider())
{
AES.Padding = PaddingMode.PKCS7;
AES.Key = key;
AES.BlockSize = 128;
AES.KeySize = 128;
AES.IV = IV;
using (FileStream fStream = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite))
{
using (ICryptoTransform crypt = AES.CreateDecryptor(key, IV))
{
using (CryptoStream crStream = new CryptoStream(fStream, crypt, CryptoStreamMode.Read))
{
using (StreamReader reader = new StreamReader(crStream))
{
//breaks here
string data = reader.ReadToEnd();
File.WriteAllText(filePath.Replace(".encrypted", ""), data);
}
}
}
}
}
}
Related
My problem is that the created encrypted zip file is unable to open after decrypting it. It says the compressed file is invalid. File it self almost doubled it's initial space after decrypting from 15 KB to 27 KB. The problem occours on zip files, when I encrypted and decryped a xml file it worked just fine. Below my whole code.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using System.IO;
namespace EDI
{
public class EncryptionHelper
{
public void Main()
{
var file = #"C:\Temp\test.zip";
AesCryptoServiceProvider AES = new AesCryptoServiceProvider();
AES.Padding = PaddingMode.PKCS7;
AES.Mode = CipherMode.CBC;
AES.BlockSize = 128;
AES.KeySize = 128;
AES.GenerateKey();
AES.GenerateIV();
var key = AES.Key;
var iv = AES.IV;
encryptAES(AES, file, key, iv);
decryptAES(AES, file + ".encrypted", key, iv);
}
public void encryptAES(SymmetricAlgorithm algo, string filePath, byte[] key, byte[] IV)
{
using (FileStream fin = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
using (FileStream fout = new FileStream(filePath + ".encrypted", FileMode.OpenOrCreate, FileAccess.Write))
{
using (ICryptoTransform crypt = algo.CreateEncryptor(key, IV))
{
using (CryptoStream crStream = new CryptoStream(fout, crypt, CryptoStreamMode.Write))
{
fin.CopyTo(crStream);
}
}
}
}
}
public void decryptAES(SymmetricAlgorithm algo, string filePath, byte[] key, byte[] IV)
{
using (FileStream fStream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
using (ICryptoTransform crypt = algo.CreateDecryptor(key, IV))
{
using (CryptoStream crStream = new CryptoStream(fStream, crypt, CryptoStreamMode.Read))
{
using (StreamReader reader = new StreamReader(crStream))
{
string data = reader.ReadToEnd();
File.WriteAllText(filePath.Replace(".encrypted", ".restored"), data);
}
}
}
}
}
}
}
Edit to show the fix.
using (FileStream writer = new FileStream(filePath + ".decrypted", FileMode.Create, FileAccess.Write))
// using (Read reader = new StreamReader(crStream))
{
// string data = reader.ReadToEnd();
// File.WriteAllText(filePath.Replace(".encrypted", ".restored"), data);
crStream.CopyTo(writer);
}
Sonarlint is warning me a bout a critical security risk on my encrypt routines
I don't understand why it triggers the first aes.CreateEncryptor(aes.Key, aes.IV); but not the second
Sonar gives me an example on how to fix it, but if the IV is generated randomly, how do I get it back in the decrypt part ?
and why is the sonar example called Encrypt() and not generateRandomIV() ?
I found these on SO I believe
Can someone help me out?
public static string EncryptString(string plainText, string key)
{
byte[] iv = new byte[16];
byte[] array;
using (Aes aes = Aes.Create())
{
aes.Key = Encoding.UTF8.GetBytes(key);
aes.IV = iv;
ICryptoTransform encryptor = aes.CreateEncryptor(aes.Key, aes.IV);
using (MemoryStream memoryStream = new MemoryStream())
{
using (CryptoStream cryptoStream = new CryptoStream((Stream)memoryStream, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter streamWriter = new StreamWriter((Stream)cryptoStream))
{
streamWriter.Write(plainText);
}
array = memoryStream.ToArray();
}
}
}
return Convert.ToBase64String(array);
}
public static string DecryptString(string cipherText, string key)
{
byte[] iv = new byte[16];
byte[] buffer = Convert.FromBase64String(cipherText);
using (Aes aes = Aes.Create())
{
aes.Key = Encoding.UTF8.GetBytes(key);
aes.IV = iv;
ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, aes.IV);
using (MemoryStream memoryStream = new MemoryStream(buffer))
{
using (CryptoStream cryptoStream = new CryptoStream((Stream)memoryStream, decryptor, CryptoStreamMode.Read))
{
using (StreamReader streamReader = new StreamReader((Stream)cryptoStream))
{
return streamReader.ReadToEnd();
}
}
}
}
}
sonar example:
public byte[] Encrypt(byte[] key, byte[] data, MemoryStream target)
{
using var aes = new AesCryptoServiceProvider();
var encryptor = aes.CreateEncryptor(key, aes.IV); // aes.IV is automatically generated to random secure value
using var cryptoStream = new CryptoStream(target, encryptor, CryptoStreamMode.Write);
cryptoStream.Write(data);
return aes.IV;
}
I have problem with reading from encrypted files. have 2 sources of files, one is Rapsberry PI (Java), the second is desktop appliaction (.Net 4.6.1).
When I'm creating a encrypted file on my device and then want to read it in my desktop app, there is no problem with decrypting and encoding to string.
In the same app I create the same file, adding next element to list in the file on each 5s. When I read the file in my app, I got Unexpected end when reading json. path error.
I have checked models and they are both the same and valid.
For encryption/decryption I'm using AES algorithm.
There is my code from my desktop app:
Writing data:
Aes myAes = Aes.Create();
myAes.Key = Encoding.ASCII.GetBytes("abcde");
byte[] roundtrip = EncryptStringToBytes_Aes(output, myAes.Key, myAes.IV);
DirectoryInfo info = new DirectoryInfo(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments));
string pathSave =info + "\\test.plkx";
using (FileStream sourceStream = new FileStream (pathSave , FileMode.Append))
{
sourceStream.Write(roundtrip, 0, roundtrip.Length);
};
The method byte[] EncryptStringToBytes_Aes(string plainText, byte[] Key, byte[] IV)
using (Aes aesAlg = Aes.Create())
{
aesAlg.Key = Key;
aesAlg.IV = IV;
aesAlg.Mode = CipherMode.ECB;
// Create a decrytor to perform the stream transform.
ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);
// Create the streams used for encryption.
using (MemoryStream msEncrypt = new MemoryStream())
{
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
//Write all data to the stream.
swEncrypt.Write(plainText);
}
encrypted = msEncrypt.ToArray();
}
}
}
// Return the encrypted bytes from the memory stream.
return encrypted;
There is my reader:
byte[] data = null;
data = new byte[fileStream.Length];
fileStream.Position = 0;
fileStream.Read(data, 0, (int)fileStream.Length);
Aes myAes = Aes.Create();
myAes.Key = Encoding.ASCII.GetBytes("abcde");
byte[] roundtrip = DecryptStringFromBytes_Aes(data, myAes.Key, myAes.IV);
return new MemoryStream(roundtrip);
And byte[] DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV) method:
byte[] plaintext = null;
using (Aes aesAlg = Aes.Create())
{
aesAlg.Mode = CipherMode.ECB;
aesAlg.Key = Key;
aesAlg.IV = IV;
ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
using (MemoryStream msDecrypt = new MemoryStream())
{
using (var csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Write))
{
csDecrypt.Write(cipherText, 0, cipherText.Length);
}
plaintext = msDecrypt.ToArray();
var ads = ASCIIEncoding.ASCII.GetString(plaintext);
//There I got exception
var ab = DeserializeStream(new MemoryStream(plaintext));
}
}
return plaintext;
DeserializeStream method:
public RecorderValueTest DeserializeStream(MemoryStream stream)
{
RecorderValueTest r = new RecorderValueTest();
using (BsonDataReader reader = new BsonDataReader(stream))
{
JsonSerializer serializer = new JsonSerializer();
r = serializer.Deserialize<RecorderValueTest>(reader);
}
return r;
}
edit
I have tried this:
xxx = new xxx
{
data = listRecord,
};
string output = JsonConvert.SerializeObject(plkx);
try
{
using (BsonDataReader reader = new BsonDataReader(new MemoryStream(Encoding.UTF8.GetBytes(output))))
{
JsonSerializer serializer = new JsonSerializer();
var r = serializer.Deserialize<xxx>(reader);
}
} catch (Exception exc)
{ }
and still get the same error while deserialization. JsonConvert.DeserializeObject<xxx>(plkx); also didn't work.
I have a Security class that Encode and Decode string, but when I try do decode - something going wrong.
Here is my Security class:
class Security
{
public static String encrypt(String imput, String key)
{
String cipherText;
var rijndael = new RijndaelManaged()
{
Key = Encoding.Unicode.GetBytes(key),
Mode = CipherMode.ECB,
BlockSize = 128,
Padding = PaddingMode.Zeros,
};
ICryptoTransform encryptor = rijndael.CreateEncryptor(rijndael.Key, null);
using (var memoryStream = new MemoryStream())
{
using (var cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
{
using (var streamWriter = new StreamWriter(cryptoStream))
{
streamWriter.Write(imput);
streamWriter.Flush();
}
cipherText = Convert.ToBase64String(memoryStream.ToArray());
}
}
return cipherText;
}
public static String decrypt(String imput, String key)
{
byte[] data = Convert.FromBase64String(imput);
String decrypted;
using (RijndaelManaged rijAlg = new RijndaelManaged())
{
rijAlg.Key = Encoding.UTF8.GetBytes(key);
rijAlg.Mode = CipherMode.ECB;
rijAlg.BlockSize = 128;
rijAlg.Padding = PaddingMode.Zeros;
ICryptoTransform decryptor = rijAlg.CreateDecryptor(rijAlg.Key, null);
using (MemoryStream msDecrypt = new MemoryStream(data))
{
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
decrypted = srDecrypt.ReadToEnd();
}
}
}
}
return decrypted;
}
}
In program.cs:
String A = Security.encrypt("text", "1234567891234567");
A = Security.decrypt(A, "1234567891234567");
Finaly it return something like that: �%����;\0�\a��f6 , but I need original string. Where I made a mistake?
Use the same encoding in both methods, either Encoding.Unicode or Encoding.UTF8
Please help me modify this code to encrypt/decrypt in blocks instead of huge byte arrays! the code that converts the file and calls the encryption class is:
Console.Write("Enter File Path: ");
docPath = Console.ReadLine();
extension = docPath.Substring(docPath.IndexOf(".")).Trim();
byte[] binarydata = File.ReadAllBytes(docPath);
text = System.Convert.ToBase64String(binarydata, 0, binarydata.Length);
var Encrypted = AESCryptography.Encrypt(text, m.ToString(), extension);
using (FileStream fs = File.Create(docPath.Substring(0,docPath.IndexOf(".")) + ".aent"))
{
Byte[] info = new UTF8Encoding(true).GetBytes(Encrypted);
// Add some information to the file.
fs.Write(info, 0, info.Length);
}
And the class that does the actual encryption is this:
public static class AESCryptography
{
private const int keysize = 256;
public static string Encrypt(string plainText, string passPhrase, string extention)
{
byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);
using (PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null))
{
byte[] keyBytes = password.GetBytes(keysize / 8);
using (RijndaelManaged symmetricKey = new RijndaelManaged())
{
symmetricKey.GenerateIV();
symmetricKey.Mode = CipherMode.CBC;
using (ICryptoTransform encryptor = symmetricKey.CreateEncryptor(keyBytes, symmetricKey.IV))
{
using (MemoryStream memoryStream = new MemoryStream())
{
using (CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
{
cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
cryptoStream.FlushFinalBlock();
byte[] cipherTextBytes = memoryStream.ToArray();
return Convert.ToBase64String(cipherTextBytes) + "\n" + Convert.ToBase64String(symmetricKey.IV) + "\n" + extention;
}
}
}
}
}
}
public static string Decrypt(string cipherText, string passPhrase, string initVector)
{
byte[] initVectorBytes = Convert.FromBase64String(initVector);
byte[] cipherTextBytes = Convert.FromBase64String(cipherText);
using (PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null))
{
byte[] keyBytes = password.GetBytes(keysize / 8);
using (RijndaelManaged symmetricKey = new RijndaelManaged())
{
symmetricKey.Mode = CipherMode.CBC;
using (ICryptoTransform decryptor = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes))
{
using (MemoryStream memoryStream = new MemoryStream(cipherTextBytes))
{
using (CryptoStream cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read))
{
byte[] plainTextBytes = new byte[cipherTextBytes.Length];
int decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
return Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount);
}
}
}
}
}
}
}
I need the encryption class to be able to encrypt files as big as ~2.5GB.
I have tried multiple times, most didn't work others didn't even encrypt!
Please Help! I need to present this tomorrow!
You can 'chain' streams to encrypt large files, so you don't need to hold them in memory.
See answer from anton-gogolev https://stackoverflow.com/a/38629596/1776231 for question AES-Encrypt-then-MAC a large file with .NET
using(var encryptedFileStream = File.OpenWrite("..."))
using(var macCryptoStream = new CryptoStream(encryptedFileStream, mac, CryptoStreamMode.Write))
using(var encryptCryptoStream = new CryptoStream(macCryptoStream, encryptor, CryptoStreamMode.Write))
using(var inputFileStream = File.OpenRead("..."))
inputFileStream.CopyTo(encryptCryptoStream);