Objective-C

secp256k1 Key Generation and Keccak-256

See more ECC Examples

Starting in v11.0.0, Chilkat supports both secp256k1 key generation and Keccak-256 directly. These algorithms are typically used for Bitcoin and Ethereum. Objective-C

#import <CkoPrng.h>
#import <NSString.h>
#import <CkoEcc.h>
#import <CkoPrivateKey.h>
#import <CkoStringBuilder.h>
#import <CkoBinData.h>

BOOL success = NO;

// 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 ECDSA private key.
CkoPrng *fortuna = [[CkoPrng alloc] init];
NSString *entropy = [fortuna GetEntropy: [NSNumber numberWithInt: 32] encoding: @"base64"];
success = [fortuna AddEntropy: entropy encoding: @"base64"];

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

// Generate a random ECDSA private key on the secp256k1 curve.
CkoPrivateKey *privKey = [[CkoPrivateKey alloc] init];
success = [ecc GenKey: @"secp256k1" prng: fortuna privKey: privKey];
if (success == NO) {
    NSLog(@"%@",ecc.LastErrorText);
    return;
}

NSLog(@"%@",@"Successfully generated a sec256k1 key.");

// Show how to compute the Keccak-256 hash in a few ways.
CkoStringBuilder *sb = [[CkoStringBuilder alloc] init];
[sb Append: @"hello"];

NSLog(@"%@%@",@"keccak-256: ",[sb GetHash: @"keccak-256" encoding: @"hex_lower" charset: @"utf-8"]);

// Output:
// keccak-256: 1c8aff950685c2ed4bc3174f3472287b56d9517b9c948127319a09a7a36deac8

// To keccak-256 hash binary data
CkoBinData *bd = [[CkoBinData alloc] init];
[bd AppendEncoded: @"00010203040506" encoding: @"hex"];

NSLog(@"%@%@",@"keccak-256: ",[bd GetHash: @"keccak-256" encoding: @"hex_lower"]);

// Output:
// keccak-256: 801560412425120fa609be232d6fa71c7f64f42aee7977267687dcc0a2f5aa63