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PHP Extension

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?

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$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.
$key = new CkSshKey();
$key->put_Password('key_password');

$success = $key->FromOpenSshPrivateKey($key->loadText('qa_data/my_private_key_file'));
if ($success == false) {
    print $key->lastErrorText() . "\n";
    exit;
}

$sftp = new CkSFtp();

$success = $sftp->Connect('sftp.example.com',22);
if ($success == false) {
    print $sftp->lastErrorText() . "\n";
    exit;
}

// Authenticate using both a password and private key.
$success = $sftp->AuthenticatePwPk('myLogin','myPassword',$key);
if ($success == true) {
    print 'Authentication is successful!' . "\n";
    exit;
}

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

$json = new CkJsonObject();
$sftp->GetLastJsonData($json);

$json->put_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:
print 'authResult: ' . $json->stringOf('authResult') . "\n";
print 'authFailReason: ' . $json->stringOf('authFailReason') . "\n";

?>