How to Encrypt and Decrypt

Question

How to encrypt json object using aes256 with cbc and pkcs5 padding. i did with base64 i dont have idea about aes256 pls help me Thanks in Advance

Jaya Prakash · Answer

@Rajkiran Swain sir, Pls provide code also for Decryption thank you.

Rajkiran Swain · Answer

Sure, I can help you with that. Here's an example code snippet in C# that uses the built-in System.Security.Cryptography library to encrypt a JSON object using AES-256 with CBC mode and PKCS5 padding in ASP.NET: using System; using System.IO; using System.Text; using System.Security.Cryptography; using Newtonsoft.Json; // Define the JSON object to encrypt var data = new { name = "John Doe", age = 30, email = "john.doe@example.com" }; // Convert the JSON object to a string var json_data = JsonConvert.SerializeObject(data); // Define the encryption key and initialization vector (IV) var key = Encoding.UTF8.GetBytes("secretkey1234567"); // 16-byte key for AES-256 var iv = Encoding.UTF8.GetBytes("initialvector123"); // 16-byte IV for CBC mode // Create a new AES cipher with CBC mode and PKCS5 padding var aes = Aes.Create(); aes.Mode = CipherMode.CBC; aes.Padding = PaddingMode.PKCS7; aes.KeySize = 256; aes.BlockSize = 128; aes.Key = key; aes.IV = iv; // Convert the data to a byte array var json_bytes = Encoding.UTF8.GetBytes(json_data); // Pad the data to a multiple of 16 bytes using PKCS5 padding var block_size = aes.BlockSize / 8; var padding = block_size - (json_bytes.Length % block_size); var padded_data = new byte[json_bytes.Length + padding]; Array.Copy(json_bytes, padded_data, json_bytes.Length); for (int i = json_bytes.Length; i

Amit Mohanty · Answer

Try this using System; using System.Security.Cryptography; using System.Text; using Newtonsoft.Json; public class Program { public static void Main() { // Sample JSON object var jsonObject = new { Name = "Amit", Age = 35, Address = "Hyderabad" }; // Generate a random 256-bit encryption key and a 128-bit initialization vector (IV) byte[] key = new byte[32]; using (var rng = new RNGCryptoServiceProvider()) { rng.GetBytes(key); } byte[] iv = new byte[16]; using (var rng = new RNGCryptoServiceProvider()) { rng.GetBytes(iv); } // Convert the JSON object to a string and encode it in UTF-8 format string jsonString = JsonConvert.SerializeObject(jsonObject); byte[] jsonBytes = Encoding.UTF8.GetBytes(jsonString); // Encrypt the JSON bytes using the AES cipher with CBC mode and PKCS5 padding byte[] encryptedBytes; using (Aes aes = Aes.Create()) { aes.Key = key; aes.IV = iv; aes.Mode = CipherMode.CBC; aes.Padding = PaddingMode.PKCS7; using (var encryptor = aes.CreateEncryptor()) { encryptedBytes = encryptor.TransformFinalBlock(jsonBytes, 0, jsonBytes.Length); } } string encryptedString = Encoding.UTF8.GetString(encryptedBytes); // Decrypt the encrypted bytes using the same AES cipher with CBC mode and PKCS5 padding byte[] decryptedBytes; using (Aes aes = Aes.Create()) { aes.Key = key; aes.IV = iv; aes.Mode = CipherMode.CBC; aes.Padding = PaddingMode.PKCS7; using (var decryptor = aes.CreateDecryptor()) { decryptedBytes = decryptor.TransformFinalBlock(encryptedBytes, 0, encryptedBytes.Length); } } // Convert the decrypted bytes back to a JSON object string decryptedString = Encoding.UTF8.GetString(decryptedBytes); var decryptedJsonObject = JsonConvert.DeserializeObject(decryptedString); // Print the original and decrypted JSON objects Console.WriteLine("Original JSON object: " + jsonString); Console.WriteLine("Encrypted JSON object: " + encryptedString); Console.WriteLine("Decrypted JSON object: " + decryptedString); } }

Amit Mohanty · Answer

Hey Jaya Prakash, can you please provide sample of your json data ?

Jaya Prakash · Answer

@Amit Not Working sir, throwing exception the input data is not a complete block.