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C#

SFTP Public-Key Authentication (id_ed25519)

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

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C#
bool success = false;

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

Chilkat.SshKey key = new Chilkat.SshKey();

//  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-----

string privKeyText = key.LoadText("c:/temp/id_ed25519");
if (key.LastMethodSuccess != true) {
    Debug.WriteLine(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 != true) {
    Debug.WriteLine(key.LastErrorText);
    return;
}

Chilkat.SFtp sftp = new Chilkat.SFtp();

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

string hostname = "sftp.example.com";
int port = 22;
success = sftp.Connect(hostname,port);
if (success != true) {
    Debug.WriteLine(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",key);
if (success != true) {
    Debug.WriteLine(sftp.LastErrorText);
    return;
}

Debug.WriteLine(sftp.LastErrorText);
Debug.WriteLine("Public-Key Authentication Successful!");

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