ElGamal 签名未验证

Question

我想从此 link https://csharp.hotexamples.com/examples/Portable.Licensing.Security.Cryptography.ElGamal/ElGamalKeyStruct/-/php-elgamalkeystruct-class-examples.html

实施 ElGamal 加密

这是我到目前为止尝试过的方法，但没有成功

string lic = "abcdefghijklmnopqrstuvwxyz";
byte[] licenseKey = Encoding.UTF8.GetBytes(lic);

ElGamalKeyStruct key = new ElGamalKeyStruct();
key.P = new BigInteger(123567890);
key.G = new BigInteger(1234567890);
key.Y = new BigInteger(1234567890);
key.X = new BigInteger(0); //zero

byte[] signature = CreateSignature(licenseKey, key);
bool verified = VerifySignature(licenseKey, signature, key);

VerifySignature总是returnsfalse.

Answer 1

P 必须是素数。请参阅 here（即您使用的代码出自的电子书）：

Create a random prime number, p. This number is the ElGamal "modulus." The number of bits required to represent p is the size of the public key, so that if p is represented using 1024 bits, then the key created by following the protocol is a 1024-bit key. We will select 607 as our example value.

如果您查看文本，就会找到生成 El Gamal 密钥的代码（CreateKeyPair() 方法）

ElGamal 签名未验证

ElGamal signature not verified

c#

encryption

elgamal