我感兴趣的是,为什么加密/解密只能在磁盘文件上使用小的0字节大小,但是停止使用较大的文件,我会收到错误The input data is not a complete block
和Index was outside the bounds of the array
。
我使用ECDiffieHellmanCng在两侧生成相同的对称密钥。
加密端密钥交换:
using (ECDiffieHellmanCng sendingMode = new ECDiffieHellmanCng())
{
sendingMode.KeyDerivationFunction = ECDiffieHellmanKeyDerivationFunction.Hash;
sendingMode.HashAlgorithm = CngAlgorithm.Sha256;
sendersPublicKey = sendingMode.PublicKey.ToByteArray();
CngKey secretKey = CngKey.Import(receiversPublicKey, CngKeyBlobFormat.EccPublicBlob);
sendersKey = sendingMode.DeriveKeyMaterial(CngKey.Import(receiversPublicKey, CngKeyBlobFormat.EccPublicBlob));
byte[] encryptedFile = null;
byte[] ivFile = null;
byte[] fileBytes = File.ReadAllBytes(fileToSendPath);
Encryption(sendersKey, fileBytes, out encryptedFile, out ivFile);
}
接收方交流:
using (ECDiffieHellmanCng receivingMode = new ECDiffieHellmanCng())
{
receivingMode.KeyDerivationFunction = ECDiffieHellmanKeyDerivationFunction.Hash;
receivingMode.HashAlgorithm = CngAlgorithm.Sha256;
receiversPublicKey = receivingMode.PublicKey.ToByteArray();
CngKey secretKey = CngKey.Import(sendersPublicKey, CngKeyBlobFormat.EccPublicBlob);
receiversKey = receivingMode.DeriveKeyMaterial(CngKey.Import(sendersPublicKey, CngKeyBlobFormat.EccPublicBlob));
byte[] decryptedFile = new byte[50000000];
Decryption(encryptedFile, ivFile, out decryptedFile);
}
加密/解密方法:
private void Encryption(byte[] key, byte[] unencryptedMessage,out byte[] encryptedMessage, out byte[] iv)
{
using (Aes aes = new AesCryptoServiceProvider())
{
aes.Key = key;
iv = aes.IV;
// Encrypt the message
using (MemoryStream ciphertext = new MemoryStream())
using (CryptoStream cs = new CryptoStream(ciphertext, aes.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(unencryptedMessage, 0, unencryptedMessage.Length);
cs.Close();
encryptedMessage = ciphertext.ToArray();
}
}
}
private void Decryption(byte[] encryptedMessage, byte[] iv, out byte[] decryptedMessage)
{
using (Aes aes = new AesCryptoServiceProvider())
{
aes.Key = receiversKey;
aes.IV = iv;
// Decrypt the message
using (MemoryStream decryptedBytes = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(decryptedBytes, aes.CreateDecryptor(), CryptoStreamMode.Write))
{
cs.Write(encryptedMessage, 0, encryptedMessage.Length);
cs.Close();
decryptedMessage = decryptedBytes.ToArray();
}
}
}
}
答案 0 :(得分:1)
AES是一种分组密码,要求输入为块大小倍数,AES为16字节。简单的解决方案是使用PKCS#7(néePKCS#5)填充选项,填充将在加密时透明地添加,并在解密时删除。