C＃使用SignedCms驗證數字簽名

Question

我得到CryptographicException「哈希值不正確。」我試過verifyCms.CheckSignature（true）; （同樣的錯誤） 我試圖在ContentInfo添加整個郵件（發件人，主題，正文，HTML Sectione ...）（同樣的錯誤）

public static bool Verify(byte[] signature, X509Certificate2 certificate) 
{ 
     X509Certificate2 cert=new X509Certificate2(@"D:\Work\Digital Signature\smime.p7s"); 
    certificate = cert; 

    if(signature == null) 
     throw new ArgumentNullException("signature"); 
    if(certificate == null) 
     throw new ArgumentNullException("certificate"); 

    //the text from the body of the mail  
    string text = "FINAL TEST SIGNED"; 
    //hash the text 
    // Methode 3 for Hashing 
      System.Security.Cryptography.SHA1 hash3 = System.Security.Cryptography.SHA1.Create(); 
      System.Text.UnicodeEncoding encoder = new System.Text.UnicodeEncoding(); 
      byte[] combined = encoder.GetBytes(text); 
      byte[] hash3byte = hash3.ComputeHash(combined); 

    //Adding the text from the email, to a contentInfo 
     ContentInfo content = new ContentInfo(hash3byte); 

    // decode the signature 
    SignedCms verifyCms = new SignedCms(content,true); 
    verifyCms.Decode(signature); 

    // verify it 
    try 
    { 
     verifyCms.CheckSignature(new X509Certificate2Collection(certificate), false); 
     return true; 
    } 
    catch(CryptographicException) 
    { 
     return false; 
    } 
} 

問題出在哪裏？

Answer 1

你可以看到我的帖子 How to Use RSAEncryption to create PKCS7/CMS with SHA1 digest?

只是改變的Oid「SHA1」給你所需要的算法。