Objective-C

RSA Sign with PKCS8 Encrypted Key

See more RSA Examples

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature. Objective-C

#import <CkoPrivateKey.h>
#import <CkoRsa.h>
#import <NSString.h>

BOOL success = NO;

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

CkoPrivateKey *pkey = [[CkoPrivateKey alloc] init];

// Load the private key from an RSA PEM file:
success = [pkey LoadPkcs8EncryptedFile: @"privateKey.key" password: @"myPassword"];

CkoRsa *rsa = [[CkoRsa alloc] init];

// Import the private key into the RSA object:
success = [rsa UsePrivateKey: pkey];
if (success == NO) {
    NSLog(@"%@",rsa.LastErrorText);
    return;
}

// Return the signature in hex
rsa.EncodingMode = @"hex";

NSString *strData = @"This is the string to be signed.";

// Sign the string using the sha-1 hash algorithm.
// Other valid choices are "md2", "sha256", "sha384", "sha512",  and "md5".
NSString *hexSig = [rsa SignStringENC: strData hashAlg: @"sha-1"];

NSLog(@"%@",hexSig);