支付相关-算法知识2

参考资料：Enveloped and Signed CMS/PKCS #7 Message

资料地址：https://docs.microsoft.com/en-us/previous-versions/bb885086(v=vs.90)?redirectedfrom=MSDN

参考资料：

资料地址：

File name: Examples/CSharp/AsposePDF/DigitallySign.cs

using System.IO;
using System;
using Aspose.Pdf;
using Aspose.Pdf.Facades;
using System.Collections;
using Aspose.Pdf.Forms;

namespace Aspose.Pdf.Examples.CSharp.AsposePDF.SecuritySignatures
{
    public class DigitallySign
    {
        public static void Run()
        {
            try
            {
                // ExStart:DigitallySign
                // The path to the documents directory.
                string dataDir = RunExamples.GetDataDir_AsposePdf_SecuritySignatures();
                string pbxFile = "";
                string inFile = dataDir + @"DigitallySign.pdf";
                string outFile = dataDir + @"DigitallySign_out.pdf";
                using (Document document = new Document(inFile))
                {
                    using (PdfFileSignature signature = new PdfFileSignature(document))
                    {
                        PKCS7 pkcs = new PKCS7(pbxFile, "WebSales"); // Use PKCS7/PKCS7Detached objects
                        DocMDPSignature docMdpSignature = new DocMDPSignature(pkcs, DocMDPAccessPermissions.FillingInForms);
                        System.Drawing.Rectangle rect = new System.Drawing.Rectangle(100, 100, 200, 100);
                        // Set signature appearance
                        signature.SignatureAppearance = dataDir + @"aspose-logo.jpg";
                        // Create any of the three signature types
                        signature.Certify(1, "Signature Reason", "Contact", "Location", true, rect, docMdpSignature);
                        // Save output PDF file
                        signature.Save(outFile);
                    }
                }

                using (Document document = new Document(outFile))
                {
                    using (PdfFileSignature signature = new PdfFileSignature(document))
                    {
                        IList sigNames = signature.GetSignNames();
                        if (sigNames.Count > 0) // Any signatures?
                        {
                            if (signature.VerifySigned(sigNames[0] as string)) // Verify first one
                            {
                                if (signature.IsCertified) // Certified?
                                {
                                    if (signature.GetAccessPermissions() == DocMDPAccessPermissions.FillingInForms) // Get access permission
                                    {
                                        // Do something
                                    }
                                }
                            }
                        }
                    }
                }
                // ExEnd:DigitallySign
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }
    }
}

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参考资料：Encrypt and Decrypt Data with C#

资料地址：https://www.codeproject.com/articles/14151/encrypt-and-decrypt-data-with-csharp-2

public static string Encrypt(string toEncrypt, bool useHashing)
{
    byte[] keyArray;
    byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);

    System.Configuration.AppSettingsReader settingsReader = new AppSettingsReader();
    // Get the key from config file

    string key = (string)settingsReader.GetValue("SecurityKey", typeof(String));
    //System.Windows.Forms.MessageBox.Show(key);
    //If hashing use get hashcode regards to your key
    if (useHashing)
    {
        MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
        keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
        //Always release the resources and flush data
        //of the Cryptographic service provide. Best Practice

        hashmd5.Clear();
    }
    else
        keyArray = UTF8Encoding.UTF8.GetBytes(key);

    TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
    //set the secret key for the tripleDES algorithm
    tdes.Key = keyArray;
    //mode of operation. there are other 4 modes. We choose ECB(Electronic code Book)
    tdes.Mode = CipherMode.ECB;
    //padding mode(if any extra byte added)
    tdes.Padding = PaddingMode.PKCS7;

    ICryptoTransform cTransform = tdes.CreateEncryptor();
    //transform the specified region of bytes array to resultArray
    byte[] resultArray = cTransform.TransformFinalBlock
            (toEncryptArray, 0, toEncryptArray.Length);
    //Release resources held by TripleDes Encryptor
    tdes.Clear();
    //Return the encrypted data into unreadable string format
    return Convert.ToBase64String(resultArray, 0, resultArray.Length);
}

public static string Decrypt(string cipherString, bool useHashing)
{
    byte[] keyArray;
    //get the byte code of the string

    byte[] toEncryptArray = Convert.FromBase64String(cipherString);

    System.Configuration.AppSettingsReader settingsReader = new AppSettingsReader();
    //Get your key from config file to open the lock!
    string key = (string)settingsReader.GetValue("SecurityKey", typeof(String));

    if (useHashing)
    {
        //if hashing was used get the hash code with regards to your key
        MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
        keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
        //release any resource held by the MD5CryptoServiceProvider

        hashmd5.Clear();
    }
    else
    {
        //if hashing was not implemented get the byte code of the key
        keyArray = UTF8Encoding.UTF8.GetBytes(key);
     }

    TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
    //set the secret key for the tripleDES algorithm
    tdes.Key = keyArray;
    //mode of operation. there are other 4 modes.
    //We choose ECB(Electronic code Book)

    tdes.Mode = CipherMode.ECB;
    //padding mode(if any extra byte added)
    tdes.Padding = PaddingMode.PKCS7;

    ICryptoTransform cTransform = tdes.CreateDecryptor();
    byte[] resultArray = cTransform.TransformFinalBlock
            (toEncryptArray, 0, toEncryptArray.Length);
    //Release resources held by TripleDes Encryptor
    tdes.Clear();
    //return the Clear decrypted TEXT
    return UTF8Encoding.UTF8.GetString(resultArray);
}

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参考资料：https://www.c-sharpcorner.com/UploadFile/f8fa6c/data-encryption-and-decryption-in-C-Sharp/

资料地址：Data Encryption And Decryption in C#

using System;  
using System.Security.Cryptography;  
using System.Text;  
   
namespace DataEncrypterDecrypter  
{  
    public class CryptoEngine  
    {  
        public static string Encrypt(string input, string key)  
        {  
            byte[] inputArray = UTF8Encoding.UTF8.GetBytes(input);  
            TripleDESCryptoServiceProvider tripleDES = new TripleDESCryptoServiceProvider();  
            tripleDES.Key = UTF8Encoding.UTF8.GetBytes(key);  
            tripleDES.Mode = CipherMode.ECB;  
            tripleDES.Padding = PaddingMode.PKCS7;  
            ICryptoTransform cTransform = tripleDES.CreateEncryptor();  
            byte[] resultArray = cTransform.TransformFinalBlock(inputArray, 0, inputArray.Length);  
            tripleDES.Clear();  
            return Convert.ToBase64String(resultArray, 0, resultArray.Length);  
        }  
        public static string Decrypt(string input, string key)  
        {  
            byte[] inputArray = Convert.FromBase64String(input);  
            TripleDESCryptoServiceProvider tripleDES = new TripleDESCryptoServiceProvider();  
            tripleDES.Key = UTF8Encoding.UTF8.GetBytes(key);  
            tripleDES.Mode = CipherMode.ECB;  
            tripleDES.Padding = PaddingMode.PKCS7;  
            ICryptoTransform cTransform = tripleDES.CreateDecryptor();  
            byte[] resultArray = cTransform.TransformFinalBlock(inputArray, 0, inputArray.Length);  
            tripleDES.Clear();   
            return UTF8Encoding.UTF8.GetString(resultArray);  
        }  
    }  
}