PHP ssh2_auth_pubkey_file not working with encrypted private key

Question

I am using ssh2 in PHP, as follows:

$connection = ssh2_connect($host, $port);
ssh2_auth_pubkey_file($connection, $username, $pubKey, $privKey, $passphrase);

This results in the error message:

ssh2_auth_pubkey_file(): Authentication failed for username using public key

I am however, able to connect fine by using sftp directly in a terminal.

$ sftp -oPort=PORT -i /path/to/private/key USER@HOST

(The sftp command responds to ask for the passphrase, and it then connects.)

I'm at a bit of a loss with debugging this - the ssh2 commands are asking for and being provided with all the relevant information to connect, and I can connect fine using sftp directly in a terminal. What might the problem be?

Answer 1

I ended up ditching ssh2 for phpseclib.

First, load the private key as follows:

$key = new Crypt_RSA();
$key->setPassword($passphrase);
$key->loadKey(file_get_contents($keyPath));

Then login using the key:

$sftp = new Net_SFTP($host, $port);
$loginResult = $sftp->login($username, $key);