Objective-C

Get ECC Private Key in JWK Format (JSON Web Key)

See more ECC Examples

Demonstrates how to get an ECC private key in JWK (JSON Web Key) format.

Note: This example requires Chilkat v9.5.0.66 or later.

Objective-C

#import <CkoStringBuilder.h>
#import <CkoPrivateKey.h>
#import <NSString.h>
#import <CkoJsonObject.h>

BOOL success = NO;

//  Note: This example requires Chilkat v9.5.0.66 or later.

//  Load a PEM file into memory.
CkoStringBuilder *sbPem = [[CkoStringBuilder alloc] init];
success = [sbPem LoadFile: @"qa_data/pem/ecc_privKey.pem" charset: @"utf-8"];
if (success != YES) {
    NSLog(@"%@",@"Failed to load PEM file.");
    return;
}

//  Load the PEM into a private key object.
CkoPrivateKey *privKey = [[CkoPrivateKey alloc] init];
success = [privKey LoadPem: [sbPem GetAsString]];
if (success != YES) {
    NSLog(@"%@",privKey.LastErrorText);
    return;
}

//  Get the private key in JWK format:
NSString *jwk = [privKey GetJwk];

//  The GetJwk method will return the JWK in the most compact JSON format possible,
//  as a single line with no extra whitespace.  To get a more human-readable JWK (for this example),
//  load into a Chilkat JSON object and emit non-compact:

CkoJsonObject *json = [[CkoJsonObject alloc] init];
[json Load: jwk];
json.EmitCompact = NO;
NSLog(@"%@",@"ECC Private Key in JWK format:");
NSLog(@"%@",[json Emit]);

//  Sample output:
//  { 
//    "kty": "EC",
//    "crv": "P-256",
//    "x": "oBUyo8CQAFPeYPvv78ylh5MwFZjTCLQeb042TjiMJxE",
//    "y": "vvQyxZkUjJQUPU_0bCy3Pj5qQdfu8jwEfqEeYGZ95CU",
//    "d": "EbVzfPnZPxfAyxqEZV05laAoJAl-_6Xt2O4mOB611sM"
//  }
//  

//  Additional information can be added like this:
[json AppendString: @"use" value: @"enc"];
[json AppendString: @"kid" value: @"123ABC"];

//  Now examine the JSON:
NSLog(@"%@",[json Emit]);

//  { 
//    "kty": "EC",
//    "crv": "P-256",
//    "x": "oBUyo8CQAFPeYPvv78ylh5MwFZjTCLQeb042TjiMJxE",
//    "y": "vvQyxZkUjJQUPU_0bCy3Pj5qQdfu8jwEfqEeYGZ95CU",
//    "d": "EbVzfPnZPxfAyxqEZV05laAoJAl-_6Xt2O4mOB611sM",
//    "use": "enc",
//    "kid": "123ABC"
//  }