Sample code for 30+ languages & platforms
Objective-C

Duplicate Java Secure Token Creation

See more RSA Examples

Demonstrates how to duplicate some Java code that creates an RSA signature to create a base64 token.

Chilkat Objective-C Downloads

Objective-C
#import <CkoDateTime.h>
#import <NSString.h>
#import <CkoStringBuilder.h>
#import <CkoCert.h>
#import <CkoRsa.h>

BOOL success = NO;

// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// This example duplicates the following Java code:

// public X509Certificate2 cert = new X509Certificate2(@"Some path to p12/p12file_name.p12","Password_for_p12"); 
// 
// public string GenerateSignToken(double timeValidityMin){ 
//   string equalsSign = ":="; 
//   string timeCreated = DateTime.Now.ToString("yyyy-MM-ddTHH:mm:ss.fffzzz"); 
//   string tokenTimeInfo = "validityTimeMinutes" + equalsSign + timeValidityMin + ";"+"timeCreated" + equalsSign + timeCreated; 
//   string signature = SignData(tokenTimeInfo); 
//   string secureToken = tokenTimeInfo + ";" + "signature" + equalsSign + signature; 
//   return Base64UrlEncode(secureToken); 
// } 
//  
// public string SignData(string stringToSign){ 
//   byte[] dataToSign = Encoding.UTF8.GetBytes(stringToSign); 
//   RSACryptoServiceProvider privKey = (RSACryptoServiceProvider)cert.PrivateKey; 
//   CspKeyContainerInfo containerInfo = new RSACryptoServiceProvider().CspKeyContainerInfo; 
//   CspParameters cspparams = new CspParameters(containerInfo.ProviderType, containerInfo.ProviderName, privKey.CspKeyContainerInfo.KeyContainerName); 
//   privKey = new RSACryptoServiceProvider(cspparams); 
//   string id = CryptoConfig.MapNameToOID("SHA256"); 
//   byte[] sign = privKey.SignData(dataToSign, id); 
//   bool res = privKey.VerifyData(dataToSign, id, sign); 
//   return Convert.ToBase64String(sign).Replace('+', '-').Replace('/', '_').Replace("=", ""); 
// } 
//  
// private static string Base64UrlEncode(string input){ 
//   var inputBytes = Encoding.UTF8.GetBytes(input); 
//   return Convert.ToBase64String(inputBytes).Replace('+', '-').Replace('/', '_').Replace("=", ""); 
// } 

CkoDateTime *dt = [[CkoDateTime alloc] init];
[dt SetFromCurrentSystemTime];
NSString *timeCreated = [dt GetAsTimestamp: YES];

// Such as 2019-04-01T19:35:44-05:00
NSLog(@"%@",timeCreated);

CkoStringBuilder *sbToken = [[CkoStringBuilder alloc] init];
[sbToken Append: @"validityTimeMinutes:=10.0;timeCreated:="];
[sbToken Append: timeCreated];

CkoCert *cert = [[CkoCert alloc] init];
success = [cert LoadPfxFile: @"Some path to p12/p12file_name.p12" password: @"Password_for_p12"];
if (success != YES) {
    NSLog(@"%@",cert.LastErrorText);
    return;
}

CkoRsa *rsa = [[CkoRsa alloc] init];
success = [rsa SetX509Cert: cert usePrivateKey: YES];
if (success != YES) {
    NSLog(@"%@",rsa.LastErrorText);
    return;
}

rsa.EncodingMode = @"base64url";

NSString *signature = [rsa SignStringENC: [sbToken GetAsString] hashAlg: @"sha256"];
if (rsa.LastMethodSuccess == NO) {
    NSLog(@"%@",rsa.LastErrorText);
    return;
}

[sbToken Append: @";signature:="];
[sbToken Append: signature];

// Base64URL encode the result
[sbToken Encode: @"base64url" charset: @"utf-8"];
NSString *token = [sbToken GetAsString];

NSLog(@"%@",token);