(Objective-C) Generate an ECC Key (Public and Private)

Demonstrates how to generate an ECC key and save both public and private parts.

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#import <CkoPrng.h>
#import <NSString.h>
#import <CkoEcc.h>
#import <CkoPrivateKey.h>
#import <CkoPublicKey.h>

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

// Create a Fortuna PRNG and seed it with system entropy.
// This will be our source of random data for generating the ECC private key.
CkoPrng *fortuna = [[CkoPrng alloc] init];
NSString *entropy = [fortuna GetEntropy: [NSNumber numberWithInt: 32] encoding: @"base64"];
BOOL success = [fortuna AddEntropy: entropy encoding: @"base64"];

CkoEcc *ecc = [[CkoEcc alloc] init];

// Generate a random ECC private key on the secp256r1 curve.
// Chilkat also supports other curves, such as secp384r1, secp521r1, and secp256k1.

CkoPrivateKey *privKey = [ecc GenEccKey: @"secp256r1" prng: fortuna];
if (ecc.LastMethodSuccess == NO) {
    NSLog(@"%@",ecc.LastErrorText);
    return;
}

// Save the private key to PKCS8 encrypted PEM
// (The private key can be saved in a variety of different formats. See the online reference documentation.)
success = [privKey SavePkcs8EncryptedPemFile: @"pemPassword" path: @"qa_output/eccPrivKey.pem"];
if (success != YES) {
    NSLog(@"%@",privKey.LastErrorText);
}

// The private key PEM looks like this:

// 	-----BEGIN ENCRYPTED PRIVATE KEY-----
// 	MIHFMEAGCSqGSIb3DQEFDTAzMBsGCSqGSIb3DQEFDDAOBAhUmn+1/lwCIwICCAAw
// 	FAYIKoZIhvcNAwcECPlyNXAXZO+oBIGAIvxvTENXJWbrCwSjh0QNxLecBotUpfI5
// 	auOonLmwVMyt1ahMmNyVo/D+pnKQSE41Fg8fApM0DCDKZUOVCCcK1qirIsMPQkGp
// 	klPJbvrQRVYgzBtU31uNB5y2wqhrIeepal1HXBvbkUK0nfJMbcdz/XAEIQu2HhTD
// 	t6LMScPQld4=
// 	-----END ENCRYPTED PRIVATE KEY-----

// Now get the public key part from the private key.
// (A public key is actually a subset of the private key.)
CkoPublicKey *pubKey = [privKey GetPublicKey];

// Save the public key to a PEM file.
// (The public key can be saved in a variety of different formats. See the online reference documentation.)
// For ECC keys, the 1st argument (bPreferPkcs1) is ignored and unused.
BOOL bPreferPkcs1 = NO;
success = [pubKey SavePemFile: bPreferPkcs1 path: @"qa_output/eccPubKey.pem"];

// The public key PEM looks like this:

// 	-----BEGIN PUBLIC KEY-----
// 	MIIBSzCCAQMGByqGSM49AgEwgfcCAQEwLAYHKoZIzj0BAQIhAP////8AAAABAAAA
// 	AAAAAAAAAAAA////////////////MFsEIP////8AAAABAAAAAAAAAAAAAAAA////
// 	///////////8BCBaxjXYqjqT57PrvVV2mIa8ZR0GsMxTsPY7zjw+J9JgSwMVAMSd
// 	NgiG5wSTamZ44ROdJreBn36QBEEEaxfR8uEsQkf4vOblY6RA8ncDfYEt6zOg9KE5
// 	RdiYwpZP40Li/hp/m47n60p8D54WK84zV2sxXs7LtkBoN79R9QIhAP////8AAAAA
// 	//////////+85vqtpxeehPO5ysL8YyVRAgEBA0IABGdOH8uM6SfX3mdV+TR0mWp2
// 	gfVRPlxWxwhOiowuNByBxmQz7ZR4CJY1XcN2zkUo5pzW73ZhGwgd2XTOvqPqG40=
// 	-----END PUBLIC KEY-----
// 

NSLog(@"%@",@"finished.");