如何使用.pem文件中提供的公钥验证签名？

Question

如何使用.pem文件中提供的公钥验证签名？

我使用流动的代码:

RSACryptoServiceProvider CrRsa;

var reader21 = File.OpenText(@"C:GTLpublicKey.pem");
var x = new PemReader(reader21);
var y = (RsaKeyParameters)x.ReadObject();

CrRsa = (RSACryptoServiceProvider)RSACryptoServiceProvider.Create();
RSAParameters pa = new RSAParameters();
pa.Modulus = y.Modulus.ToByteArray();
pa.Exponent = y.Exponent.ToByteArray();
CrRsa.ImportParameters(pa);

y返回null,导致错误pa.Modulus = y.Modulus.ToByteArray();

Answer 1

RSACryptoServiceProvider RSAVerifier = new RSACryptoServiceProvider();

//Read public Key From Text File.

StreamReader PubKeyReader = File.OpenText(txtPublicKeyFile.Text);

string publicKey = PubKeyReader.ReadToEnd();

//Adding public key to RSACryptoServiceProvider object.

RSAVerifier.FromXmlString(publicKey);

//Reading the Signature to verify.

FileStream Signature = new FileStream(txtVerifySign.Text, FileMode.Open, FileAccess.Read);

BinaryReader SignatureReader = new BinaryReader(Signature);

byte[] SignatureData = SignatureReader.ReadBytes((int)Signature.Length);

//Reading the Signed File for Verification.

FileStream Verifyfile = new FileStream(txtVerifyFile.Text, FileMode.Open, FileAccess.Read);

BinaryReader VerifyFileReader = new BinaryReader(Verifyfile);

byte[] VerifyFileData = VerifyFileReader.ReadBytes((int)Verifyfile.Length);

//Comparing.

bool isValidsignature = RSAVerifier.VerifyData(VerifyFileData, "SHA1", SignatureData);

if (isValidsignature)

{

      Signature.Close();

      Verifyfile.Close();

}

else

{


    Signature.Close();

    Verifyfile.Close();

}