I'm getting the following exception when i try to encrypt a byte array with a EC public key :
java.security.InvalidKeyException: No installed provider supports this key:
sun.security.ec.ECPublicKeyImpl
This exception is generated when i call Cipher.init(). The lines below show what I did in my program:
ECPublicKey publicKey ;
ECPrivateKey privateKey;
//Generating key paire (public and private keys)
KeyPairGenerator keyGen = KeyPairGenerator.getInstance("EC", "SunEC");
SecureRandom random = SecureRandom.getInstance("SHA1PRNG", "SUN");
keyGen.initialize(571, random);
KeyPair pair = keyGen.generateKeyPair();
privateKey = (ECPrivateKey) pair.getPrivate();
publicKey = (ECPublicKey) pair.getPublic();
// get an AES cipher object with CTR encription mode
Cipher cipher = Cipher.getInstance("AES/CTR/NoPadding");
// encrypt the sharedSecret using the public key
cipher.init(Cipher.ENCRYPT_MODE, publicKey);**
byte[] result = cipher.doFinal(data);
Must I add a provider to support this public key ??
Finally, I found the source of this exception. The problem was initialization of cipher :
//This is the wrong initialization
Cipher cipher = Cipher.getInstance("AES/CTR/NoPadding");
//This is the right initialization
Cipher cipher = Cipher.getInstance("AES/CTR/NoPadding","SunJCE");
But now, i have another exception which is (it is less important than the previous one) :
java.security.InvalidKeyException: Invalid AES key length: 170 bytes
So what must I use as encrypting algorithm with ECDSA public key now ?
Related
I use AES algoritm to make a udp request in local subnet (192.168.1.x).
The Playstore shows me a warning because I use static secret key.
// Console alert refers to this method
public byte[] encryptionUtil(String key, String iv, byte[] plainText) {
Cipher cipher = Cipher.getInstance(“AES/GCM/NoPadding”);
SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), “AES”);
GCMParameterSpec paramSpec = new GCMParameterSpec(256, iv.getBytes());
cipher.init(Cipher.ENCRYPT_MODE, keySpec, paramSpec);
return cipher.doFinal(plainText);
}
// The unsafe key and initialisation vector are here and should be changed
byte[] cipherText = encryptionUtil(“abcdef...”, “010203040506”, plainText);
I'm try to make a iv random and send it in the udp packet, I publish the apk again but the playstore make the warning again.
What is the solution?
for the implementation of an API I use, I need to provide a certificate, which consists of 2 byte arrays one for the public key and the other one for private key.
My initial idea was to do this with X509Certificate object of .Net. But I am struggling to get the private key bytes.
var certificate = new X509Certificate2("testCert.pfx", password, X509KeyStorageFlags.Exportable);
byte[] myPublicKey = certificate.GetRawCertData();
byte[] privateKey = ???
I've tried to export the key, but I can't export the private key standalone.
And:
certificate.PrivateKey.ToXmlString(true);
is not available on a Ubuntu System :-(
Do you have any ideas, how to get the private bytes from certificates?
May be X509Certificate2 is not the best solution for this...
Use an approrpiate method of these X509Certificate2 extension methods:
GetRSAPrivateKey(X509Certificate2) -- for RSA keys
GetDSAPrivateKey(X509Certificate2) -- for DSA keys
GetECDsaPrivateKey(X509Certificate2) -- for EC keys
Extension method you need to use depends on asymmtric key algorithm.
I am working with encryption using AES. My customer is encrypting some of the sensitive data while posting the data to my web API. And my code will decrypt these fields before insert them to the database.
Originally we agree to use a fixed secret key. Below is the code:
public class AESEncryptor {
private static final String ALGO = "AES";
private static final String keyVal = "!5Po4#j82Adsu39/*na3n5";
public static String encrypt(String data) {
try {
Key key = genKey();
Cipher c = Cipher.getInstance(ALGO);
c.init(Cipher.ENCRYPT_MODE, key);
byte[] encVal = c.doFinal(data.getBytes());
return Base64.encodeBase64String(encVal);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public static String decrypt (String encryptedData) throws Exception{
Key key = genKey();
Cipher c = Cipher.getInstance(ALGO);
c.init(Cipher.DECRYPT_MODE, key);
byte[] data = Base64.decodeBase64(encryptedData);
byte[] decByptes = c.doFinal(data);
return new String(decByptes);
}
private static Key genKey() throws Exception {
fixKeyLength();
return new SecretKeySpec(keyVal.getBytes(), ALGO);
}
}
Then the other party suggested we should switch to KeyGenerator to generate a random secure key. Something like the following.
KeyGenerator keyGen = KeyGenerator.getInstance("AES");
keyGen.init(256);
SecretKey key = keyGen.generateKey();
final byte[] nonce = new byte[32];
SecureRandom random = SecureRandom.getInstanceStrong();
random.nextBytes(nonce);
Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");
GCMParameterSpec spec = new GCMParameterSpec(16 * 8, nonce);
cipher.init(Cipher.ENCRYPT_MODE, key, spec);
I am not sure that is possible. Because the correct decryption relies on the same key for encryption. If the key is random, how would my API know what key to use every time? Or is there a solution to handle this situation?
There is no solution to handle this problem. Symmetric encryption requires that both parties know the key in order to encrypt and decrypt. If the key is random each time, then you need a way to communicate the key.
The scheme you have designed is quite poor, since a fixed key means that the key being compromised will bring down the whole system. You're also using ECB mode, which is inherently insecure. No authentication either.
If you want to communicate data securely from one party to another, use TLS with client authentication. This is the industry standard way to solve this problem and you don't have to get your hands dirty with the crypto.
I would like to use encryption to send traffic to my F5 BIG IP load balancer and have it use its own native CRYPTO:: methods to decrypt a base64 encoded string.
I am able to encrypt and decrypt a string within the appliance and within a Visual Studio 2012 console application but I cannot decrypt an encrypted string in the opposing environment.
Any suggestion here as to how to get the following keys in a compatible format that CRYPTO or C# understands would go a long way!
// C# key and vector declaration:
private const string AesIV = #"!QAZ2WSX#EDC4RFV";
private const string AesKey = #"5TGB&YHN7UJM(IK<";
It appears that in CRYPTO:: it needs it in hex format, I tried to convert it as seen below but that didnt help me.
C# console app code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using System.Security.Cryptography;
using System.Threading;
namespace ssoconsole_encrypt
{
class Program
{
private const string AesIV = #"!QAZ2WSX#EDC4RFV";
private const string AesKey = #"5TGB&YHN7UJM(IK<";
// set key "abed1ddc04fbb05856bca4a0ca60f21e"
//set iv "d78d86d9084eb9239694c9a733904037"
// set key "56bca4a0ca60f21e"
// set iv "39694c9a73390403"
/// <summary>
/// AES Encryption
/// </summary>
///
static public string Encrypt(string text)
{
// AesCryptoServiceProvider
AesCryptoServiceProvider aes = new AesCryptoServiceProvider();
aes.BlockSize = 128;
aes.KeySize = 256;
aes.IV = Encoding.UTF8.GetBytes(AesIV);
aes.Key = Encoding.UTF8.GetBytes(AesKey);
string keyme = BitConverter.ToString(aes.Key);
string ivme = BitConverter.ToString(aes.IV);
Console.WriteLine(string.Format("The converted key is: {0}",keyme));
Console.WriteLine(string.Format("The converted iv is: {0}", ivme));
Console.WriteLine(System.Text.Encoding.UTF8.GetString(aes.Key));
// Thread.Sleep(10000);
//Console.WriteLine(aes.Key.ToString());
aes.Mode = CipherMode.CBC;
aes.Padding = PaddingMode.PKCS7;
// aes.Padding = PaddingMode.Zeros;
// Convert string to byte array
//byte[] src = Encoding.Unicode.GetBytes(text);
byte[] src = Encoding.UTF8.GetBytes(text);
// encryption
using (ICryptoTransform encrypt = aes.CreateEncryptor())
{
byte[] dest = encrypt.TransformFinalBlock(src, 0, src.Length);
// Convert byte array to Base64 strings
return Convert.ToBase64String(dest);
}
}
/// <summary>
/// AES decryption
/// </summary>
static public string Decrypt(string text)
{
// AesCryptoServiceProvider
AesCryptoServiceProvider aes = new AesCryptoServiceProvider();
aes.BlockSize = 128;
aes.KeySize = 256;
aes.IV = Encoding.UTF8.GetBytes(AesIV);
aes.Key = Encoding.UTF8.GetBytes(AesKey);
//aes.IV = Encoding.UTF8.GetBytes(#"01020304050607080900010203040506");
//aes.Key = Encoding.UTF8.GetBytes(#"01020304050607080900010203040506");
aes.Mode = CipherMode.CBC;
aes.Padding = PaddingMode.PKCS7;
// Convert Base64 strings to byte array
byte[] src = System.Convert.FromBase64String(text);
try
{
// decryption
using (ICryptoTransform decrypt = aes.CreateDecryptor())
{
byte[] dest = decrypt.TransformFinalBlock(src, 0, src.Length);
// return Encoding.Unicode.GetString(dest);
return Encoding.UTF8.GetString(dest);
}
}
catch (CryptographicException e)
{
return e.ToString();
}
}
static void Main()
{
string username = "jschoombee";
string encrypted = Encrypt(username);
string decrypted = Decrypt(encrypted);
// string decrypted = Decrypt("epvhTN55JnnVV9DBn1Cbsg==");
// string decrypted = Decrypt(encrypted);
Console.WriteLine(string.Format("jschoombee encrypted is : {0}",encrypted));
Console.WriteLine(string.Format("the Decrypted username for jp is : {0}", decrypted));
Thread.Sleep(1000000);
}
}
}
This is the Console Output:
The converted key is: 35-54-47-42-26-59-48-4E-37-55-4A-4D-28-49-4B-3C
The converted iv is: 21-51-41-5A-32-57-53-58-23-45-44-43-34-52-46-56
5TGB&YHN7UJM(IK<
jschoombee encrypted is : tGG9Un6VqcAOTQawlxwRXg==
the Decrypted username for jp is : jschoombee
This it the F5 / TCL code:
when RULE_INIT {
set static::hexkey "355447422659484E37554A4D28494B3C"
log local0.info"====Rule_Init===="
log local0.info "Key is $static::hexkey"
log local0.info"================="
}
when HTTP_REQUEST_DATA {
set iv "2151415A325753582345444334524656"
set text_to_encrypt "jschoombee"
set enc_out_no_binary [CRYPTO::encrypt -alg aes-256-cbc -keyhex $static::hexkey -ivhex $iv $text_to_encrypt]
set dec_in [CRYPTO::decrypt -alg aes-256-cbc -keyhex $static::hexkey -ivhex $iv $enc_out_no_binary]
log local0.info "The decrypted NO binary $dec_in"
log local0.info "The Encrypted NO binary Base64 is: [b64encode "$enc_out_no_binary"]"
binary scan $enc_out_no_binary H* enc_hex
log local0.info "The Encrypted NO binary Hex is: $enc_hex"
log local0.info "This is the IV $iv"
HTTP::release
}
The F5/TCL Output Log File:
Feb 11 13:05:45 AMS4-LB-01 info tmm1[9650]: <HTTP_REQUEST_DATA>: The decrypted NO binary jschoombee
Feb 11 13:05:45 AMS4-LB-01 info tmm1[9650]: <HTTP_REQUEST_DATA>: The Encrypted NO binary Base64 is: Rlz4cC9SlpRyON4cZI+dtQ==
Feb 11 13:05:45 AMS4-LB-01 info tmm1[9650]: <HTTP_REQUEST_DATA>: The Encrypted NO binary Hex is: 465cf8702f5296947238de1c648f9db5
Feb 11 13:05:45 AMS4-LB-01 info tmm1[9650]: <HTTP_REQUEST_DATA>: This is the IV 2151415A325753582345444334524656
There are some very strange things happening in your code regarding the key and IV.
First of all the key you've specified is 16 characters. In UTF-8 those result in 16 bytes. You are however specifying a key of 32 bytes (256 bits) in your C# code. Also be warned that many libraries (incorrectly) use AES-256 to mean Rijndael with a 256 bit block size. It's probably better to just use AES-128 and focus on making your protocol and code secure.
Second, a key can never be a character string. A character string normally is restricted with regards to which values can be used. E.g. control codes cannot be entered. This means that your key will never reach its intended strength. If you want to use a static key, you should specify it in hexadecimals as you do in your F5 code.
A static IV does not make much sense. The whole idea of the IV is to make sure that you will generate a different ciphertext if you encrypt a block with a value already processed. So please use a random IV, and place it in front of your ciphertext.
You seem to have the hang on using encoding/decoding on your plaintext (UTF-8) and ciphertext (Base 64). So please try and follow the advice given above and try again.
I have to write a standalone java program to decrypt password from file,using Symmetric key for password decryption. I didn't work with encryption and decryption before. can anybody give any suggestion how can i do this.I need your guidance.
maybe you need something like this
private static final String ALGORITHM = "AES";
....
....
Key key = new SecretKeySpec(new String("here is your symmetric key").getBytes(), ALGORITHM);
Cipher c = Cipher.getInstance(ALGORITHM);
//dencript mode (passes the key)
c.init(Cipher.DECRYPT_MODE, key);
//Decode base64 to get bytes
byte[] encBytes = new BASE64Decoder().decodeBuffer(encryptedValue);
// Decrypt
byte[] plainTxtBytes = c.doFinal(encBytes);
// Decode
String decryptedValue = new String(plainTxtBytes , "UTF-8");
Here are some resources:
http://www.javamex.com/tutorials/cryptography/symmetric.shtml
http://www.java2s.com/Code/Java/Security/EncryptionandDecryptionusingSymmetricKeys.htm
http://www.flexiprovider.de/examples/ExampleCrypt.html (This uses files as well)