(Objective-C) Load EC Public Key from X,Y Values

Demonstrates how to load an EC public key from X and Y values.

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#import <NSString.h>
#import <CkoJsonObject.h>
#import <CkoPublicKey.h>

BOOL success;

// We have the following x and y values in base64 (for an EC point on the P-256 curve).
NSString *x = @"Dn7uB1O7kgk74G6qfQwFJESeDnxO6lLjGZFWZJE16tw";
NSString *y = @"iOWA5DInzK6nuUGvHJbMVq1Dpj248FqSV2teN3HzmhU";

// Build a JWK that looks like this:

// {
//   "kty": "EC",
//   "crv": "P-256",
//   "x": "Dn7uB1O7kgk74G6qfQwFJESeDnxO6lLjGZFWZJE16tw",
//   "y": "iOWA5DInzK6nuUGvHJbMVq1Dpj248FqSV2teN3HzmhU"
// }

CkoJsonObject *json = [[CkoJsonObject alloc] init];
[json UpdateString: @"kty" value: @"EC"];
[json UpdateString: @"crv" value: @"P-256"];
[json UpdateString: @"x" value: x];
[json UpdateString: @"y" value: y];

// Load from the JWK.
CkoPublicKey *pubkey = [[CkoPublicKey alloc] init];
success = [pubkey LoadFromString: [json Emit]];
if (success == NO) {
    NSLog(@"%@",pubkey.LastErrorText);
    return;
}

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