我一直在尝试使用C#的Bouncy Castle API找到如何进行PBKDF2密钥派生。
但目前我真的一无所知。
我曾尝试阅读Pkcs5S2ParametersGenerator.cs和PBKDF2Params.cs文件，但我真的无法弄清楚该如何做。
根据我迄今为止所做的研究，PBKDF2需要一个字符串（或char[]），即密码、盐和迭代次数。
到目前为止，最有前途且最明显的是PBKDF2Params和Pkcs5S2ParametersGenerator。
但这些都似乎不接受字符串或char[]。
有没有人在C#中完成了这个过程或者对此有任何线索？ 或者有谁已经在Java中实现了BouncyCastle并可以提供帮助吗？
先谢谢大家 :)
更新: 我已经找到了如何在Bouncy Castle中实现此操作。请参见下面的答案 :)
BouncyCastle.Crypto.dll添加为项目的引用。using System;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Crypto.Digests;
using Org.BouncyCastle.Crypto.Macs;
using Org.BouncyCastle.Math;
using Org.BouncyCastle.Security;
namespace PBKDF2_PKCS5
{
class PBKDF2
{
private readonly IMac hMac = new HMac(new Sha1Digest());
private void F(
byte[] P,
byte[] S,
int c,
byte[] iBuf,
byte[] outBytes,
int outOff)
{
byte[] state = new byte[hMac.GetMacSize()];
ICipherParameters param = new KeyParameter(P);
hMac.Init(param);
if (S != null)
{
hMac.BlockUpdate(S, 0, S.Length);
}
hMac.BlockUpdate(iBuf, 0, iBuf.Length);
hMac.DoFinal(state, 0);
Array.Copy(state, 0, outBytes, outOff, state.Length);
for (int count = 1; count != c; count++)
{
hMac.Init(param);
hMac.BlockUpdate(state, 0, state.Length);
hMac.DoFinal(state, 0);
for (int j = 0; j != state.Length; j++)
{
outBytes[outOff + j] ^= state[j];
}
}
}
private void IntToOctet(
byte[] Buffer,
int i)
{
Buffer[0] = (byte)((uint)i >> 24);
Buffer[1] = (byte)((uint)i >> 16);
Buffer[2] = (byte)((uint)i >> 8);
Buffer[3] = (byte)i;
}
// Use this function to retrieve a derived key.
// dkLen is in octets, how much bytes you want when the function to return.
// mPassword is the password converted to bytes.
// mSalt is the salt converted to bytes
// mIterationCount is the how much iterations you want to perform.
public byte[] GenerateDerivedKey(
int dkLen,
byte[] mPassword,
byte[] mSalt,
int mIterationCount
)
{
int hLen = hMac.GetMacSize();
int l = (dkLen + hLen - 1) / hLen;
byte[] iBuf = new byte[4];
byte[] outBytes = new byte[l * hLen];
for (int i = 1; i <= l; i++)
{
IntToOctet(iBuf, i);
F(mPassword, mSalt, mIterationCount, iBuf, outBytes, (i - 1) * hLen);
}
//By this time outBytes will contain the derived key + more bytes.
// According to the PKCS #5 v2.0: Password-Based Cryptography Standard (www.truecrypt.org/docs/pkcs5v2-0.pdf)
// we have to "extract the first dkLen octets to produce a derived key".
//I am creating a byte array with the size of dkLen and then using
//Buffer.BlockCopy to copy ONLY the dkLen amount of bytes to it
// And finally returning it :D
byte[] output = new byte[dkLen];
Buffer.BlockCopy(outBytes, 0, output, 0, dkLen);
return output;
}
}
}
如何使用这个函数？很简单！ :) 以下是一个非常简单的示例，其中密码和盐由用户提供。
private void cmdDeriveKey_Click(object sender, EventArgs e)
{
byte[] salt = ASCIIEncoding.UTF8.GetBytes(txtSalt.Text);
PBKDF2 passwordDerive = new PBKDF2();
// I want the key to be used for AES-128, thus I want the derived key to be
// 128 bits. Thus I will be using 128/8 = 16 for dkLen (Derived Key Length) .
//Similarly if you wanted a 256 bit key, dkLen would be 256/8 = 32.
byte[] result = passwordDerive.GenerateDerivedKey(16, ASCIIEncoding.UTF8.GetBytes(txtPassword.Text), salt, 1000);
//result would now contain the derived key. Use it for whatever cryptographic purpose now :)
//The following code is ONLY to show the derived key in a Textbox.
string x = "";
for (int i = 0; i < result.Length; i++)
{
x += result[i].ToString("X");
}
txtResult.Text = x;
}
RNGCryptoServiceProvider 作为盐。请确保引用 System.Security.Cryptography 命名空间。RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
byte[] salt = new byte[16];
rng.GetBytes(salt);
我曾经也遇到过这个问题，找到了一种更直接的方法。至少在Bouncy Castle 1.7版本中，您可以像下面这样做（使用Org.BouncyCastle.Crypto的VB代码）：
Dim bcKeyDer As New Generators.Pkcs5S2ParametersGenerator()
bcKeyDer.Init(password, salt, keyIterations)
Dim bcparam As Parameters.KeyParameter = bcKeyDer.GenerateDerivedParameters("aes256", 256)
Dim key1() As Byte = bcparam.GetKey()
我已经将其与.NET的System.Security.Cryptography进行了测试，它有效！