5
我正在嘗試將簽名時間屬性添加到使用SignedCMS簽名的文件中。爲PKCS7簽名CMS添加簽名時間?
private byte[] signFile(byte[] fileContent, X509Certificate2 verificationCert)
{
ContentInfo contentInfo = new ContentInfo(fileContent);
SignedCms signedCMS = new SignedCms(contentInfo);
CmsSigner cmsSigner = new CmsSigner(SubjectIdentifierType.IssuerAndSerialNumber, verificationCert);
Oid signedDate = new Oid("1.2.840.113549.1.9.5"); //oid for PKCS #9 signing time
signedDate.Value = DateTime.Now.ToString();
CryptographicAttributeObject cryptoAtty = new CryptographicAttributeObject(signedDate);
cmsSigner.SignedAttributes.Add(cryptoAtty);
signedCMS.ComputeSignature(cmsSigner, false);
byte[] encoded = signedCMS.Encode();
return encoded;
}
會發生錯誤的編碼:
CryptographicException: The object identifier is poorly formatted.
如何正確添加簽約時間任何想法?我想我可能必須將簽名時間轉換爲ASN.1編碼對象,並將其添加到cryptoAtty
的值。如何將日期/時間轉換爲ASN.1編碼對象?