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我迷失了自我，我需要帮助才能朝着正确的方向前进:) 我有 nodejs 服务器，它必须与用 C# 编写的服务器交换一些关键数据，所以在这种情况下，我希望我的数据被加密不知何故。我在考虑 AES，为了安全地交换密钥，我想使用 ECDH，但我不知道如何让它正常工作......如果我想正确的方式，我可以让我的 C#“allice”像这样：

ECDiffieHellman alice = ECDiffieHellman.Create(ECCurve.NamedCurves.brainpoolP192t1);
var aliceKey = alice.PublicKey;
var ketyToExport = Convert.ToBase64String(aliceKey.ToByteArray());
//send ketyToExport to nodejs
//KEY FROM nodejs
var key1 = Convert.FromBase64String("BIzSJ1dmTXpSS8rqkVFISZ+vumhqXYMWfWoU5vB9GHhOtxxDInu/GZ92VJpqhrE3vw==").ToList();
var keyType = new byte[] { 0x45, 0x43, 0x4B, 0x31 };
var keyLength = new byte[] { 0x20, 0x00, 0x00, 0x00 };
key1.RemoveAt(0);
key1 = keyType.Concat(keyLength).Concat(key1).ToList();
byte[] bobKeyBytes = key1.ToArray();
//and I have a problem with that line bellow, I do not know how to make it work
var aliceSecret = alice.DeriveKeyMaterial(/*ECDiffieHellmanPublicKey bobKeyBytes*/);

而nodejs“鲍勃”的一面是这样的：

const crypto = require("crypto");
const bob = crypto.createECDH('brainpoolP192t1')
const bobKey = bob.generateKeys('base64');
var bobLength = Buffer.from(bobKey, 'base64').length;
//send bobkey to c#
//recive alicekey
var tmp = "RUNLUBgAAAAR9C7kO2o+vxNT/UBvvEuJHNdI8NfU4fUxUT431ER1q3kJbeUVHepoG5SWUM2NHj8="
var aliceKeyBuffer = Buffer.from(tmp, 'base64');
var aliceKey = Buffer.alloc(bobLength)
aliceKeyBuffer.copy(aliceKey, 1, 8);
aliceKey[0] = 4;
bob.computeSecret(aliceKey);
//create aes 
//get mesage and iv ...

好的，所以我已经对所有这些进行了一些调整，但现在我不知道如何处理这条线如何让它工作...... var aliceSecret = alice.DeriveKeyMaterial(/*ECDiffieHellmanPublicKey bobKeyBytes*/);

#BIG EDIT 我从 ByteArray 获得了 ECDiffieHellmanPublicKey 的帮助（使用 ECDiffieHellman NamedCurves） ，现在我遇到了另一个问题 -_- 我的节点 js 代码没有从上面更改，但 c# 看起来像：

using (ECDiffieHellman alice = ECDiffieHellman.Create(ECCurve.NamedCurves.brainpoolP256r1))
{
    var alicePublicKey = Convert.ToBase64String(alice.PublicKey.ToByteArray());
    //NODEJS brainpoolP256r1 publickey 
    var key1 = Convert.FromBase64String("BASsbkule53ARqlMBA8hYysyyoRi3xGxGnSzIJ2fS5FlLniQD/zYiiGUVydmO/BBkQwVTUo5f4OMCxVNtQ/LuMQ=");
    byte[] keyX = new byte[key1.Length / 2];
    byte[] keyY = new byte[keyX.Length];
    Buffer.BlockCopy(key1, 1, keyX, 0, keyX.Length);
    Buffer.BlockCopy(key1, 1 + keyX.Length, keyY, 0, keyY.Length);
    ECParameters parameters = new ECParameters
    {
        Curve = ECCurve.NamedCurves.brainpoolP256r1,
        Q =
        {
            X = keyX,
            Y = keyY,
        },
    };
    byte[] derivedKey;
    using (ECDiffieHellman bob = ECDiffieHellman.Create(parameters))
    using (ECDiffieHellmanPublicKey bobPublic = bob.PublicKey)
    {
        derivedKey = alice.DeriveKeyFromHash(bobPublic, HashAlgorithmName.SHA256);
    }
    var aliceKey = Convert.ToBase64String(derivedKey);
    byte[] encryptedMessage = null;
    byte[] iv = null;
    // Send(aliceKey, "Secret message", out encryptedMessage, out iv);
}

它正在工作，但它给了bob.computeSecret(aliceKey)我不同的密钥......如果 我 认为正确的话，它们应该是平等的。我想错了吗？iIoH9aJoWf3666QQ6X+kj4iUKrk9j+hbRuXbhgs7YzM=alice.DeriveKeyFromHash(bobPublic, HashAlgorithmName.SHA256);wJ7O4Hm2Jxs1FcLx6KaMmENvqdTQJPZ/YNSs1+MQDOQ=

#编辑完成！！

因此，在 js 文件末尾添加此代码给了我我需要的东西。

const hash = crypto.createHash('sha256');
var tt = bob.computeSecret(aliceKey);
hash.update(tt);
console.log(hash.digest('base64'));
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2 回答 2

2

＃＃解决方案＃＃

C＃

class Program
{
    static void Main(string[] args)
    {
        using (ECDiffieHellman alice = ECDiffieHellman.Create(ECCurve.NamedCurves.brainpoolP256r1))
        {
            var alicePublicKey = Convert.ToBase64String(alice.PublicKey.ToByteArray());
            //send alicePublicKey
            var nodejsKey = ""; //NODEJS brainpoolP256r1 publickey  base64
            byte[] nodejsKeyBytes= Convert.FromBase64String(nodejsKey);

            var aliceKey = Convert.ToBase64String(getDeriveKey(nodejsKeyBytes,alice));
            byte[] encryptedMessage = null;
            byte[] iv = null;
            // Send(aliceKey, "Secret message", out encryptedMessage, out iv);
        }
    }
    static byte[] getDeriveKey(byte[] key1, ECDiffieHellman alice)
    {
        byte[] keyX = new byte[key1.Length / 2];
        byte[] keyY = new byte[keyX.Length];
        Buffer.BlockCopy(key1, 1, keyX, 0, keyX.Length);
        Buffer.BlockCopy(key1, 1 + keyX.Length, keyY, 0, keyY.Length);
        ECParameters parameters = new ECParameters
        {
            Curve = ECCurve.NamedCurves.brainpoolP256r1,
            Q =
            {
                X = keyX,
                Y = keyY,
            },
        };
        byte[] derivedKey;
        using (ECDiffieHellman bob = ECDiffieHellman.Create(parameters))
        using (ECDiffieHellmanPublicKey bobPublic = bob.PublicKey)
        {
            return derivedKey = alice.DeriveKeyFromHash(bobPublic, HashAlgorithmName.SHA256);
        }
    }
}

节点

const crypto = require("crypto");
const bob = crypto.createECDH('brainpoolP256r1')
bob.generateKeys();
const bobKey = bob.getPublicKey('base64');
var bobLength = Buffer.from(bobKey, 'base64').length;
//send bobkey to c#
//recive alicekey

var alicePublicKey = "RUNLUCAAAAB/xP7JhSIhYIYAijyC2zHu7obB5CwfK/ynQPxcRAIhBI6OLRRcHyPo61AhfSZN3qA2vGDfWO2mrdWWvqqhVaDf";
var aliceKeyBuffer = Buffer.from(alicePublicKey, 'base64');
var aliceKey = Buffer.alloc(bobLength)
aliceKeyBuffer.copy(aliceKey, 1, 8);
aliceKey[0] = 4;
const hash = crypto.createHash('sha256');
var tt = bob.computeSecret(aliceKey);
var bobSecretKey = hash.update(tt).digest('base64');

非常感谢@bartonjs和@Maarten Bodewes

于 2018-12-03T16:56:14.000 回答
1

上面的回答对我帮助很大。我正在使用secp521r1/nistP521在 NodeJS 和 C# 中生成密钥。就我而言，调用alice.PublicKey.ToByteArray()会导致异常：

Unhandled exception. System.PlatformNotSupportedException: Operation is not supported on this platform.
   at System.Security.Cryptography.ECDiffieHellmanImplementation.ECDiffieHellmanSecurityTransforms.ECDiffieHellmanSecurityTransformsPublicKey.ToByteArray()

根据此处dotnet 运行时团队记录的问题：

ECDiffieHellmanPublicKey.ToByteArray() 没有（标准）定义的导出格式。ECDiffieHellmanPublicKeyCng 使用的版本是特定于 Windows 的，仅适用于 NIST P-256 (secp256r1)、NIST P-384 (secp384r1) 和 NIST P-521 (secp521r1)。

要创建密钥的副本，您应该使用 ExportParameters() 方法来获取丰富的 ECParameters 对象；然后可以通过 ECDiffieHellman.Create(ECParameters) 发送并读取该对象的 PublicKey 属性以取回 ECDiffieHellmanPublicKey 的第二个实例。

假设我将我的 X 和 Y 从 Alice 发送给 Bob（我使用 hex 而不是 base64），在 NodeJS 端到达相同共享密钥的相应过程如下所示：

// Alice's public key X, Y coordinates from DotNet Core
const aliceHexX = '00248F624728B17196B22005742C13D80D3DFF75BCA74AF865195E5A29F41C013653B0931BC544245402EDD7922F38692F38DCCF780CF1A9E27D3CFB5E09E53883C0';
const aliceHexY = '0043517F3B2EF33ED70EFA2BC4163E9B99558A7C2ECB7C659A12EA4024633CFA8B9FC997F0A42D30759B4280FDADC13A67A3E7BB0227047C907FAAE92E7716E8A10D';

const alicePublicKeyXBytes = Buffer.from(aliceHexX, 'hex');
const alicePublicKeyYBytes = Buffer.from(aliceHexY, 'hex');
const alicePublicKey = Buffer.concat([Buffer.from([0x04]), alicePublicKeyXBytes, alicePublicKeyYBytes])
const bobSecret = bob.computeSecret(alicePublicKey);

const hash = crypto.createHash('sha256');
hash.update(bobSecret);
const sharedSecret = hash.digest('hex');
console.log(`Shared Secret: ${sharedSecret.toString('hex')}`);
于 2020-04-24T17:40:42.740 回答