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Objective-C

Generate ed25519 Key and Save to PuTTY Format

See more SSH Key Examples

Generates an ED25519 key and saves to PuTTY format.

Note: This example requires Chilkat v9.5.0.83 or greater.

Chilkat Objective-C Downloads

Objective-C
#import <CkoSshKey.h>
#import <NSString.h>

BOOL success = NO;

// Note: Requires Chilkat v9.5.0.83 or greater.

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

CkoSshKey *key = [[CkoSshKey alloc] init];

success = [key GenerateEd25519Key];
if (success != YES) {
    NSLog(@"%@",key.LastErrorText);
    return;
}

// We can optionally set a comment to be included in the exported key.
key.Comment = @"This is my new ed25519 key.";

// Export the ed25519 private key to unencrypted PuTTY format:
BOOL exportEncrypted = NO;
NSString *exportedKey = [key ToPuttyPrivateKey: exportEncrypted];
success = [key SaveText: exportedKey path: @"qa_output/privkey_putty_unencrypted.ppk"];

// The unencrypted PuTTY key looks like this:

// 	PuTTY-User-Key-File-2: ssh-ed25519
// 	Encryption: none
// 	Comment: This is my new ed25519 key.
// 	Public-Lines: 2
// 	AAAAC3NzaC1lZDI1NTE5AAAAIJn6m7yKzkAAHXzzjE1zv4RqtdE8r5eTegcpbNDF
// 	OPYs
// 	Private-Lines: 1
// 	AAAAIFgwbZ38AR9Oiw930wsCcCGymQRBa2Y7qBq6R3HCe9VL
// 	Private-MAC: 892573676dd13ef70b6ab7ef219decdfbd5b1857

// Export the ed25519 private key to encrypted PuTTY format:
key.Password = @"secret";
exportEncrypted = YES;
exportedKey = [key ToPuttyPrivateKey: exportEncrypted];
success = [key SaveText: exportedKey path: @"qa_output/privkey_putty_encrypted.ppk"];

// The encrypted PuTTY key looks like this:

// 	PuTTY-User-Key-File-2: ssh-ed25519
// 	Encryption: aes256-cbc
// 	Comment: This is my new ed25519 key.
// 	Public-Lines: 2
// 	AAAAC3NzaC1lZDI1NTE5AAAAIJn6m7yKzkAAHXzzjE1zv4RqtdE8r5eTegcpbNDF
// 	OPYs
// 	Private-Lines: 1
// 	aIa9mY22htPElPgWhtXesp97662JECxaSsnNqvhD06P+o18immv8ohn73vI/bhQB
// 	Private-MAC: 312221dc90660859fe68df300767f8f779046815

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