(PECL ssh2 >= 0.9.0)
ssh2_connect — Connect to an SSH server
$host
[, int $port = 22
[, array $methods
[, array $callbacks
]]] )Establish a connection to a remote SSH server.
Once connected, the client should verify the server's hostkey using ssh2_fingerprint(), then authenticate using either password or public key.
host
port
methods
methods may be an associative array with up to four parameters
as described below.
| Index | Meaning | Supported Values* |
|---|---|---|
| kex | List of key exchange methods to advertise, comma separated in order of preference. | diffie-hellman-group1-sha1, diffie-hellman-group14-sha1, and diffie-hellman-group-exchange-sha1 |
| hostkey | List of hostkey methods to advertise, comma separated in order of preference. | ssh-rsa and ssh-dss |
| client_to_server | Associative array containing crypt, compression, and message authentication code (MAC) method preferences for messages sent from client to server. | |
| server_to_client | Associative array containing crypt, compression, and message authentication code (MAC) method preferences for messages sent from server to client. |
* - Supported Values are dependent on methods supported by underlying library. See » libssh2 documentation for additional information.
| Index | Meaning | Supported Values* |
|---|---|---|
| crypt | List of crypto methods to advertise, comma separated in order of preference. | rijndael-cbc@lysator.liu.se, aes256-cbc, aes192-cbc, aes128-cbc, 3des-cbc, blowfish-cbc, cast128-cbc, arcfour, and none** |
| comp | List of compression methods to advertise, comma separated in order of preference. | zlib and none |
| mac | List of MAC methods to advertise, comma separated in order of preference. | hmac-sha1, hmac-sha1-96, hmac-ripemd160, hmac-ripemd160@openssh.com, and none** |
Note: Crypt and MAC method "none"
For security reasons, none is disabled by the underlying » libssh2 library unless explicitly enabled during build time by using the appropriate ./configure options. See documentation for the underlying library for more information.
callbacks
callbacks may be an associative array with any
or all of the following parameters.
| Index | Meaning | Prototype |
|---|---|---|
| ignore |
Name of function to call when an
SSH2_MSG_IGNORE packet is received
|
void ignore_cb($message) |
| debug |
Name of function to call when an
SSH2_MSG_DEBUG packet is received
|
void debug_cb($message, $language, $always_display) |
| macerror |
Name of function to call when a packet is received but the
message authentication code failed. If the callback returns
TRUE, the mismatch will be ignored, otherwise the connection
will be terminated.
|
bool macerror_cb($packet) |
| disconnect |
Name of function to call when an
SSH2_MSG_DISCONNECT packet is received
|
void disconnect_cb($reason, $message, $language) |
Returns a resource on success, or FALSE on error.
Example #1 ssh2_connect() example
Open a connection forcing 3des-cbc when sending packets, any strength aes cipher when receiving packets, no compression in either direction, and Group1 key exchange.
<?php
/* Notify the user if the server terminates the connection */
function my_ssh_disconnect($reason, $message, $language) {
printf("Server disconnected with reason code [%d] and message: %s\n",
$reason, $message);
}
$methods = array(
'kex' => 'diffie-hellman-group1-sha1',
'client_to_server' => array(
'crypt' => '3des-cbc',
'comp' => 'none'),
'server_to_client' => array(
'crypt' => 'aes256-cbc,aes192-cbc,aes128-cbc',
'comp' => 'none'));
$callbacks = array('disconnect' => 'my_ssh_disconnect');
$connection = ssh2_connect('shell.example.com', 22, $methods, $callbacks);
if (!$connection) die('Connection failed');
?>
Steve Kamerman (2011-07-05 15:06:07)
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.]
suri dot suribala dot com (2005-02-24 05:00:09)
With Sara's help, I have the following SS2 class that is quite flexible. If anyone improves it, please feel free to let me know.
<?php
// ssh protocols
// note: once openShell method is used, cmdExec does not work
class ssh2 {
private $host = 'host';
private $user = 'user';
private $port = '22';
private $password = 'password';
private $con = null;
private $shell_type = 'xterm';
private $shell = null;
private $log = '';
function __construct($host='', $port='' ) {
if( $host!='' ) $this->host = $host;
if( $port!='' ) $this->port = $port;
$this->con = ssh2_connect($this->host, $this->port);
if( !$this->con ) {
$this->log .= "Connection failed !";
}
}
function authPassword( $user = '', $password = '' ) {
if( $user!='' ) $this->user = $user;
if( $password!='' ) $this->password = $password;
if( !ssh2_auth_password( $this->con, $this->user, $this->password ) ) {
$this->log .= "Authorization failed !";
}
}
function openShell( $shell_type = '' ) {
if ( $shell_type != '' ) $this->shell_type = $shell_type;
$this->shell = ssh2_shell( $this->con, $this->shell_type );
if( !$this->shell ) $this->log .= " Shell connection failed !";
}
function writeShell( $command = '' ) {
fwrite($this->shell, $command."\n");
}
function cmdExec( ) {
$argc = func_num_args();
$argv = func_get_args();
$cmd = '';
for( $i=0; $i<$argc ; $i++) {
if( $i != ($argc-1) ) {
$cmd .= $argv[$i]." && ";
}else{
$cmd .= $argv[$i];
}
}
echo $cmd;
$stream = ssh2_exec( $this->con, $cmd );
stream_set_blocking( $stream, true );
return fread( $stream, 4096 );
}
function getLog() {
return $this->log;
}
}
?>