ASP.NET AES 암호화 클래스

C#

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            // 클래스 호출
            Security AES = new Security();
            // 키32자리
            string key = "12345678901234567890123456789012";

            // 암호화 문자열
            string str = "암호화할 문자열입니다.";
            // 암호화된 문자열
            string result1 = AES.AES_encrypt(str, key);

            // 암호화된 문자열 출력
            Console.WriteLine(result1);

            // 복호화된 문자열
            string result2 = AES.AES_decrypt(result1, key);
            // 복호화된 문자열 출력
            Console.WriteLine(result2);

        }
    }

    public class Security
    {
        public string AES_encrypt(string input, string key)
        {
            RijndaelManaged aes = new RijndaelManaged();
            aes.KeySize = 256;
            aes.BlockSize = 128;
            aes.Mode = CipherMode.CBC;
            aes.Padding = PaddingMode.PKCS7;
            aes.Key = Encoding.UTF8.GetBytes(key);
            aes.IV = new Byte[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
            var encrypt = aes.CreateEncryptor(aes.Key, aes.IV);
            Byte[] xBuff = null;
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, encrypt, CryptoStreamMode.Write))
                {
                    Byte[] xXml = Encoding.UTF8.GetBytes(input);
                    cs.Write(xXml, 0, xXml.Length);
                }
                xBuff = ms.ToArray();
            }
            return Convert.ToBase64String(xBuff);
        }

        public string AES_decrypt(string input, string key)
        {
            if (input == "") { return ""; }
            RijndaelManaged aes = new RijndaelManaged();
            aes.KeySize = 256;
            aes.BlockSize = 128;
            aes.Mode = CipherMode.CBC;
            aes.Padding = PaddingMode.PKCS7;
            aes.Key = Encoding.UTF8.GetBytes(key);
            aes.IV = new Byte[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
            var decrypt = aes.CreateDecryptor();
            Byte[] xBuff = null;

            using (MemoryStream ms = new MemoryStream())
            {
                try
                {
                    using (CryptoStream cs = new CryptoStream(ms, decrypt, CryptoStreamMode.Write))
                    {
                        Byte[] xXml = Convert.FromBase64String(input);
                        cs.Write(xXml, 0, xXml.Length);
                    }
                }
                catch
                {
                    return "";
                }
                xBuff = ms.ToArray();
            }
            if (xBuff.Length > 0)
            {
                string Output = Encoding.UTF8.GetString(xBuff);
                return Output.Trim();
            }
            else
            {
                return "";
            }
        }
    }
}

---

Visual Basic

Imports System.IO
Imports System.Security.Cryptography
Imports System.Text

Module Module1

    Sub Main()
        '클래스 호출
        Dim AES As Security = New Security()
        '키32자리
        Dim key As String = "12345678901234567890123456789012"

        '암호화 문자열
        Dim str As String = "암호화할 문자열입니다."

        '암호화된 문자열
        Dim result1 As String = AES.AES_encrypt(str, key)

        '암호화된 문자열 출력
        Console.WriteLine(result1)

        '복호화된 문자열
        Dim result2 As String = AES.AES_decrypt(result1, key)
        '복호화된 문자열 출력
        Console.WriteLine(result2)
    End Sub

    Private Class Security
        Function AES_encrypt(ByVal input As String, ByVal key As String) As String
            Dim aes As RijndaelManaged = New RijndaelManaged
            aes.KeySize = 256
            aes.BlockSize = 128
            aes.Mode = CipherMode.CBC
            aes.Padding = PaddingMode.PKCS7
            aes.Key = Encoding.UTF8.GetBytes(key)
            aes.IV = New Byte() {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
            Dim encrypt = aes.CreateEncryptor(aes.Key, aes.IV)
            Dim xBuff As Byte() = Nothing
            Using ms As MemoryStream = New MemoryStream()
                Using cs As CryptoStream = New CryptoStream(ms, encrypt, CryptoStreamMode.Write)
                    Dim xXml As Byte() = Encoding.UTF8.GetBytes(input)
                    cs.Write(xXml, 0, xXml.Length)
                End Using
                xBuff = ms.ToArray()
            End Using
            Dim Output As String = Convert.ToBase64String(xBuff)
            Return Output
        End Function

        Function AES_decrypt(ByVal input As String, ByVal key As String) As String
            If input = "" Then Return ""
            Dim aes As RijndaelManaged = New RijndaelManaged
            aes.KeySize = 256
            aes.BlockSize = 128
            aes.Mode = CipherMode.CBC
            aes.Padding = PaddingMode.PKCS7
            aes.Key = Encoding.UTF8.GetBytes(key)
            aes.IV = New Byte() {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
            Dim decrypt = aes.CreateDecryptor()
            Dim xBuff As Byte() = Nothing
            Using ms As MemoryStream = New MemoryStream()
                Try
                    Using cs As CryptoStream = New CryptoStream(ms, decrypt, CryptoStreamMode.Write)
                        Dim xXml As Byte() = Convert.FromBase64String(input)
                        cs.Write(xXml, 0, xXml.Length)
                    End Using
                Catch ex As Exception

                End Try
                xBuff = ms.ToArray()
            End Using
            If IsDBNull(xBuff) Then
                Return ""
            Else
                Dim Output As String = Encoding.UTF8.GetString(xBuff)
                Return Output.Trim()
            End If
        End Function
    End Class
End Module