Due to a lack of complete examples, here's a simple SSH2 class for connecting to a server, authenticating with public key authentication, verifying the server's fingerprint, issuing commands and reading their STDOUT and properly disconnecting. Note: You may need to make sure you commands produce output so the response can be pulled. Some people suggest that the command is not executed until you pull the response back.
<?php
class NiceSSH {
// SSH Host
private $ssh_host = 'myserver.example.com';
// SSH Port
private $ssh_port = 22;
// SSH Server Fingerprint
private $ssh_server_fp = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';
// SSH Username
private $ssh_auth_user = 'username';
// SSH Public Key File
private $ssh_auth_pub = '/home/username/.ssh/id_rsa.pub';
// SSH Private Key File
private $ssh_auth_priv = '/home/username/.ssh/id_rsa';
// SSH Private Key Passphrase (null == no passphrase)
private $ssh_auth_pass;
// SSH Connection
private $connection;
public function connect() {
if (!($this->connection = ssh2_connect($this->ssh_host, $this->ssh_port))) {
throw new Exception('Cannot connect to server');
}
$fingerprint = ssh2_fingerprint($this->connection, SSH2_FINGERPRINT_MD5 | SSH2_FINGERPRINT_HEX);
if (strcmp($this->ssh_server_fp, $fingerprint) !== 0) {
throw new Exception('Unable to verify server identity!');
}
if (!ssh2_auth_pubkey_file($this->connection, $this->ssh_auth_user, $this->ssh_auth_pub, $this->ssh_auth_priv, $this->ssh_auth_pass)) {
throw new Exception('Autentication rejected by server');
}
}
public function exec($cmd) {
if (!($stream = ssh2_exec($this->connection, $cmd))) {
throw new Exception('SSH command failed');
}
stream_set_blocking($stream, true);
$data = "";
while ($buf = fread($stream, 4096)) {
$data .= $buf;
}
fclose($stream);
return $data;
}
public function disconnect() {
$this->exec('echo "EXITING" && exit;');
$this->connection = null;
}
public function __destruct() {
$this->disconnect();
}
}
?>
[EDIT BY danbrown AT php DOT net: Contains two bugfixes suggested by 'AlainC' in user note #109185 (removed) on 26-JUN-2012.]