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Objective-C

SFTP Public-Key Authentication (id_ed25519)

See more SFTP Examples

Demonstrates how to authenticate with an SSH/SFTP server using publickey authentication with an Ed25519 private key (id_ed25519).

Chilkat Objective-C Downloads

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

BOOL success = NO;

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

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

// The id_ed25519 file should contain something like this:
// (You can open it in a text editor..)

// -----BEGIN OPENSSH PRIVATE KEY-----
// b3BlbnNzaC1rZXktdjEAAAAACmFlczI1Ni1jdHIAAAAGYmNyeXB0AAAAGAAAABDIeK9+Xw
// 6Do9gnhtrJu5iJAAAAZAAAAAEAAAAzAAAAC3NzaC1lZDI1NTE5AAAAIMh/Ge7fjQCssmVd
// BqjYZbRAI0pY8IrnB6J1yLetq34OAAAAoMVP7cvy4hTiAINA3I4v55OonkpKza8mzfUW18
// RDQeYL3ovCVaAYOGcCpf/SW3QiY6tnXq+5WDEfJ7Z/kQ0nl2+1wSLOytxpyO+IY0rRtLrX
// 6e/agR4nbZpt/MFG6xqcNASbtDgg+9IWGvDrtXOLFofx07/zml+UjFL0tXRpCjOxeqKyXH
// t8SRgdT97d9/bYPwapaXY+b2DVVy5/LVx4Sq8=
// -----END OPENSSH PRIVATE KEY-----

NSString *privKeyText = [key LoadText: @"c:/temp/id_ed25519"];
if (key.LastMethodSuccess != YES) {
    NSLog(@"%@",key.LastErrorText);
    return;
}

// If your private key was saved encrypted, then you'll need the password.
// In this example, the password "blahblah" is valid for the above key -- which is a real Ed25519 key generated/saved from puttygen.
key.Password = @"blahblah";

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

CkoSFtp *sftp = [[CkoSFtp alloc] init];

// Set some timeouts, in milliseconds:
sftp.ConnectTimeoutMs = [NSNumber numberWithInt:5000];
sftp.IdleTimeoutMs = [NSNumber numberWithInt:15000];

NSString *hostname = @"sftp.example.com";
int port = 22;
success = [sftp Connect: hostname port: [NSNumber numberWithInt: port]];
if (success != YES) {
    NSLog(@"%@",sftp.LastErrorText);
    return;
}

// Authenticate with the SSH server.  Chilkat SFTP supports
// both password-based authenication as well as public-key
// authentication.  
success = [sftp AuthenticatePk: @"myLogin" privateKey: key];
if (success != YES) {
    NSLog(@"%@",sftp.LastErrorText);
    return;
}

NSLog(@"%@",sftp.LastErrorText);
NSLog(@"%@",@"Public-Key Authentication Successful!");

// Now go do whatever you're app needs to do...