How to encrypt data in rsa/ecb/pkcs1Padding in Csharp

#1

Can anyone provide code in cSharp

#2

Kindly use this https://www.devglan.com/online-tools/rsa-encryption-decryption

#3

I need C# implementation of RSA encryption and decryption with Cipher Type - RSA/ECB/PKCS1Padding.

#4

Try This code.

String pubB64 = PHRConstants.publickey;
String text = strText;
byte[] textBytes = System.Text.Encoding.UTF8.GetBytes(text);
byte[] publicKeyBytes = Convert.FromBase64String(pubB64);

        var keyLengthBits = 2048;  // need to know length of public key in advance!
        byte[] exponent = new byte[3];
        byte[] modulus = new byte[keyLengthBits / 8];
        Array.Copy(publicKeyBytes, publicKeyBytes.Length - exponent.Length, exponent, 0, exponent.Length);
        Array.Copy(publicKeyBytes, publicKeyBytes.Length - exponent.Length - 2 - modulus.Length, modulus, 0, modulus.Length);

        RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
        RSAParameters rsaKeyInfo = rsa.ExportParameters(false);
        rsaKeyInfo.Modulus = modulus;
        rsaKeyInfo.Exponent = exponent;
        rsa.ImportParameters(rsaKeyInfo);
        byte[] encrypted = rsa.Encrypt(textBytes, RSAEncryptionPadding.Pkcs1);
        return Convert.ToBase64String(encrypted);
#5

@ ChinmayGokhale can you Please confirm that below code is working for you or not ?

#6

@AyushAgarwal i try this code and generate encrypted OTP with public key , but API https://healthidsbx.abdm.gov.in/api/v2/document/verify/mobile/otp gives error msg as incorrect OTP . can you please guide us in issue.

#7

Please use this C# method for encrypting the data for V2 API

using System.Reflection;
using System.Security.Cryptography;

public async static Task RsaEncode(string message, bool encode = true)
{
try
{
if (encode && !string.IsNullOrEmpty(message))
{
byte[] byteData = Encoding.UTF8.GetBytes(message);
string path = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), @“abdm_public_key.pem”);
string publicKeyString = File.ReadAllText(path);
var rsaPublicKey = RSA.Create();
rsaPublicKey.ImportFromPem(publicKeyString);
byte[] bytesEncrypted = rsaPublicKey.Encrypt(byteData, RSAEncryptionPadding.Pkcs1);
return await Task.FromResult(Convert.ToBase64String(bytesEncrypted));
}
else
{
return await Task.FromResult(message);
}
}
catch (Exception ex)
{
ex.ToString();
}

return await Task.FromResult(string.Empty);
}

#8

can someone pls provide the code in java as well

#9

i have used this code to encryt aadhar. but when i posted that encrypted value, im getting respone as invalid loginid