added standard curve25519 decryption

This commit is contained in:
Kevin Froman 2020-05-09 23:19:47 -05:00
parent bbeaa837a9
commit d25e94816e
No known key found for this signature in database
GPG Key ID: BF1CE85F428B8CE3
2 changed files with 44 additions and 4 deletions

View File

@ -13,6 +13,32 @@ namespace Curve25519Tests
{ {
} }
[Test]
public void TestCurve25519Decrypt()
{
var alice = PublicKeyBox.GenerateKeyPair();
var bob = PublicKeyBox.GenerateKeyPair();
string message = "Hello World";
byte[] message_bytes = UTF8Encoding.UTF8.GetBytes(message);
byte[] nonce = Sodium.PublicKeyBox.GenerateNonce();
byte[] encrypted =
Sodium.PublicKeyBox.Create(
message,
nonce,
alice.PrivateKey,
bob.PublicKey
);
byte[] both = new byte[nonce.Length + encrypted.Length];
Buffer.BlockCopy(nonce, 0, both, 0, nonce.Length);
Buffer.BlockCopy(encrypted, 0, both, nonce.Length, encrypted.Length);
byte[] decrypted = chestcrypto.Curve25519.decrypt(bob.PrivateKey, alice.PublicKey, both);
string decrypted_string = Encoding.UTF8.GetString(decrypted, 0, decrypted.Length);
if (! decrypted_string.Equals(message)){
Assert.Fail();
}
}
[Test] [Test]
public void TestCurve25519Encrypt() public void TestCurve25519Encrypt()
{ {
@ -26,15 +52,13 @@ namespace Curve25519Tests
byte[] encrypted_without_nonce = new byte[encrypted_with_nonce.Length - 24]; byte[] encrypted_without_nonce = new byte[encrypted_with_nonce.Length - 24];
int counter = 0; int counter = 0;
Console.WriteLine(encrypted_without_nonce.Length);
for (int i = 24; i < encrypted_with_nonce.Length; i++){ for (int i = 24; i < encrypted_with_nonce.Length; i++){
//Console.WriteLine(counter);
encrypted_without_nonce[counter] = encrypted_with_nonce[i]; encrypted_without_nonce[counter] = encrypted_with_nonce[i];
counter += 1; counter += 1;
} }
for (int i = 0; i < chestcrypto.Curve25519.NONCE_BYTE_AMOUNT; i++){ for (int i = 0; i < chestcrypto.Curve25519.NONCE_BYTE_AMOUNT; i++){
//Console.WriteLine(i);
used_nonce[i] = encrypted_with_nonce[i]; used_nonce[i] = encrypted_with_nonce[i];
} }
for (int i = 0; i < chestcrypto.Curve25519.NONCE_BYTE_AMOUNT; i++){ for (int i = 0; i < chestcrypto.Curve25519.NONCE_BYTE_AMOUNT; i++){
@ -44,7 +68,6 @@ namespace Curve25519Tests
} }
byte[] decrypted = PublicKeyBox.Open(encrypted_without_nonce, used_nonce, bob.PrivateKey, alice.PublicKey); byte[] decrypted = PublicKeyBox.Open(encrypted_without_nonce, used_nonce, bob.PrivateKey, alice.PublicKey);
if (!Encoding.UTF8.GetString(decrypted, 0, decrypted.Length).Equals(message)){ if (!Encoding.UTF8.GetString(decrypted, 0, decrypted.Length).Equals(message)){
Console.WriteLine(Encoding.UTF8.GetString(decrypted, 0, decrypted.Length));
Assert.Fail(); Assert.Fail();
} }
} }

View File

@ -5,6 +5,7 @@ namespace chestcrypto {
public static int NONCE_BYTE_AMOUNT = 24; public static int NONCE_BYTE_AMOUNT = 24;
public static byte[] encrypt(byte[] privkey, byte[] pubkey, byte[] message){ public static byte[] encrypt(byte[] privkey, byte[] pubkey, byte[] message){
// Take a byte message and priv/pubkey for authenticated encryption and return encrypted data with prepended nonce
byte[] nonce = Sodium.PublicKeyBox.GenerateNonce(); byte[] nonce = Sodium.PublicKeyBox.GenerateNonce();
return ByteCombiner.Combine return ByteCombiner.Combine
(nonce, (nonce,
@ -15,5 +16,21 @@ namespace chestcrypto {
pubkey pubkey
)); ));
} }
public static byte[] decrypt(byte[] privkey, byte[] pubkey, byte[] message){
byte[] nonce = new byte[NONCE_BYTE_AMOUNT];
byte[] encrypted = new byte[message.Length - NONCE_BYTE_AMOUNT];
int counter = 0;
for (int i = 0; i < message.Length; i++){
if (i < NONCE_BYTE_AMOUNT){
nonce[i] = message[i];
continue;
}
encrypted[counter] = message[i];
counter += 1;
}
return Sodium.PublicKeyBox.Open(encrypted, nonce, privkey, pubkey);
}
} }
} }