SignedCms ComputeSignature抛出CryptographicException＆＃34;参数不正确。＆＃34;

Question

我尝试使用http://www.debenu.com/kb/advanced-options-signing-pdf-files/

签署pdf

但是在调用时会抛出异常

// Sign the file data (generates an SHA-1 hash and
// signs that hash)
byte[] enc = SignData(fileData, cert); //throw exception

这是我的SignData函数

    private static byte[] SignData(byte[] inputData, X509Certificate2 cert)
    {
        // Create an SHA-1 hash of the file data
        SHA1 sha = new SHA1CryptoServiceProvider();
        byte[] sha1Result = sha.ComputeHash(inputData);

        CmsSigner cmsSigner = new CmsSigner(cert);
        cmsSigner.IncludeOption = X509IncludeOption.WholeChain;
        cmsSigner.DigestAlgorithm = new Oid("SHA1");

        // Sign the hash using the certificate
        // This could be changed to use a hardware device (eg. smartcard)
        ContentInfo content = new ContentInfo(sha1Result);
        SignedCms signedCms = new SignedCms(SubjectIdentifierType.IssuerAndSerialNumber, content, true);
        signedCms.ComputeSignature(cmsSigner, false); //throw "The parameter is incorrect." 
        return signedCms.Encode();
    }

获取testSig

时没关系

    byte[] randomData = new byte[1];
    randomData[0] = 123;
    byte[] testSig = SignData(randomData, cert);

EDIT 当我使用来自usb令牌的cert时抛出此错误。如果我选择其他证书有私钥，则不会抛出错误