(Objective-C) Write PKCS1 or PKCS8 Public Key PEM

Demonstrates how to write either PKCS1 or PKCS8 format PEM files. PKCS1 public keys have this PEM format:

-----BEGIN RSA PUBLIC KEY-----
BASE64 ENCODED DATA
-----END RSA PUBLIC KEY-----

-----BEGIN PUBLIC KEY-----
BASE64 ENCODED DATA
-----END PUBLIC KEY-----

Chilkat Objective-C Library Downloads MAC OS X (Cocoa) Libs iOS Libs

#import <CkoGlobal.h>
#import <CkoPem.h>

// Unlock the Chilkat API.
// Starting in v9.5.0.49, all Chilkat classes can be unlocked at once at the beginning of a program
// by calling UnlockBundle.  It requires a Bundle unlock code.
CkoGlobal *chilkatGlob = [[CkoGlobal alloc] init];
BOOL success = [chilkatGlob UnlockBundle: @"Anything for 30-day trial."];
if (success != YES) {
    NSLog(@"%@",chilkatGlob.LastErrorText);
    return;
}

CkoPem *pem = [[CkoPem alloc] init];

// Load a public key from a PEM file.
// (Assume the PEM contains at least one public key..)
success = [pem LoadPemFile: @"/Users/chilkat/testData/pem/myPublicKey.pem"];
if (success != YES) {
    NSLog(@"%@",pem.LastErrorText);
    return;
}

int i;
int numPublicKeys = [pem.NumPublicKeys intValue];
if (numPublicKeys == 0) {
    NSLog(@"%@",(@"Error: Expected the PEM to contain public keys."));
    return;
}

// Get each public key as PEM, first in PKCS1 format, then in PKCS8.
for (i = 1; i <= numPublicKeys; i++) {

    // First output to PKCS1 PEM format:
    NSLog(@"%@",@"This is PKCS1 format:");
    pem.PublicKeyFormat = @"pkcs1";
    NSLog(@"%@",[pem ToPem]);

    // Now PKCS8 PEM format:
    NSLog(@"%@",@"This is PKCS8 format:");
    pem.PublicKeyFormat = @"pkcs8";
    NSLog(@"%@",[pem ToPem]);

}