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C#

SFTP Auth Failure Reason (AuthenticatePwPk)

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This example demonstrates how to determine the failure reason for the case where both a password and private key are required for authentication. If authentication fails, was it because of an invalid private key, or an invalid password?

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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.

// Load a private key to be used for SSH authentication.
Chilkat.SshKey key = new Chilkat.SshKey();
key.Password = "key_password";

success = key.FromOpenSshPrivateKey(key.LoadText("qa_data/my_private_key_file"));
if (success == false) {
    Debug.WriteLine(key.LastErrorText);
    return;
}

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

success = sftp.Connect("sftp.example.com",22);
if (success == false) {
    Debug.WriteLine(sftp.LastErrorText);
    return;
}

// Authenticate using both a password and private key.
success = sftp.AuthenticatePwPk("myLogin","myPassword",key);
if (success == true) {
    Debug.WriteLine("Authentication is successful!");
    return;
}

// If we get here, it means the authentication failed.
// Examine the last JSON data..

Chilkat.JsonObject json = new Chilkat.JsonObject();
sftp.GetLastJsonData(json);

json.EmitCompact = false;

// This is the JSON if the key is correct, but the password is incorrect:

// {
//   "public_key_type": "rsa",
//   "partialAuthResult": "publickey success. continue to authenticate with password...",
//   "authResult": "failed",
//   "authFailReason": "Password is incorrect"
// }

// This is the JSON if the key is incorrect.  We won't know if the password is also incorrect until
// the key is made correct so that authentication proceeds to check the password.

// {
//   "public_key_type": "rsa",
//   "authResult": "failed",
//   "authFailReason": "Key is incorrect"
// }

// To get the authResult anbd authFailReason:
Debug.WriteLine("authResult: " + json.StringOf("authResult"));
Debug.WriteLine("authFailReason: " + json.StringOf("authFailReason"));