SSH -- Running Commands that Prompt for Additional Input, such as "su"

Demonstrates how to run a shell command via SSH where the shell command prompts for additional input from the client. This example demonstrates "su".

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use chilkat();

#  Important: It is helpful to send the contents of the
#  ssh.LastErrorText property when requesting support.

$ssh = new chilkat::CkSsh();

#  Any string automatically begins a fully-functional 30-day trial.
$success = $ssh->UnlockComponent("30-day trial");
if ($success != 1) {
    print $ssh->lastErrorText() . "\n";
    exit;
}

#  Hostname may be an IP address or hostname:
$hostname = "192.168.1.117";
$port = 22;

#  Keep a session log, which is available via the SessionLog
#  property:
$ssh->put_KeepSessionLog(1);

$success = $ssh->Connect($hostname,$port);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  When reading, if no additional data arrives for more than
#  5 seconds, then abort:
$ssh->put_IdleTimeoutMs(5000);

#  SSH Server Authentication
#  If there is no login/password required, you must still call
#  AuthenticatePw and use any values for login/password.
$success = $ssh->AuthenticatePw("chilkat","myPassword");
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Open a session channel.

$channelNum = $ssh->OpenSessionChannel();
if ($channelNum < 0) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Request a pseudo-terminal
$termType = "dumb";
$widthInChars = 120;
$heightInChars = 40;
$pixWidth = 0;
$pixHeight = 0;
$success = $ssh->SendReqPty($channelNum,$termType,$widthInChars,$heightInChars,$pixWidth,$pixHeight);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Start a shell on the channel:
$success = $ssh->SendReqShell($channelNum);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Send the su command.
#  (The SSH server I'm using for testing is a Linux Ubuntu
#  system running OpenSSH.  It is important in this case to send a bare-LF
#  and not a CRLF.)

$cmd = "su\n";
$success = $ssh->ChannelSendString($channelNum,$cmd,"ansi");
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Read until we get the prompt for the password:
$success = $ssh->ChannelReceiveUntilMatch($channelNum,"Password:","ansi",1);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Display what we've received so far:
print $ssh->getReceivedText($channelNum,"ansi") . "\r\n";

#  Send the password.
#  Again, make sure it uses a bare-LF and not a CRLF.

$password = "myPassword\n";
$success = $ssh->ChannelSendString($channelNum,$password,"ansi");
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Read the response until we get the shell prompt (assuming it's successful)
#  In my case, the shell prompt is: "root@ubuntu:/home/chilkat# "
#  It will be different in your case.
$success = $ssh->ChannelReceiveUntilMatch($channelNum,'root@ubuntu:/home/chilkat#',"ansi",1);
if ($success != 1) {
    #  Check the last-error information and the session log...
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    #  Check to see what was received.
    print $ssh->getReceivedText($channelNum,"ansi") . "\r\n";
    exit;
}

#  Display what we've received so far.  This clears
#  the internal receive buffer, which is important.
#  After we send the command, we'll be reading until
#  the next command prompt.  If the command prompt
#  is already in the internal receive buffer, we'll think we're
#  already finished...
print $ssh->getReceivedText($channelNum,"ansi") . "\r\n";

#  Send a command.  In this case, we are sending the "ls" command:
$cmd = "ls\n";
$success = $ssh->ChannelSendString($channelNum,$cmd,"ansi");
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Read until the next command prompt:
$success = $ssh->ChannelReceiveUntilMatch($channelNum,'root@ubuntu:/home/chilkat#',"ansi",1);
if ($success != 1) {
    #  Check the last-error information and the session log...
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    #  Check to see what was received.
    print $ssh->getReceivedText($channelNum,"ansi") . "\r\n";
    exit;
}

#  Display the command output:
print $ssh->getReceivedText($channelNum,"ansi") . "\r\n";

#  You may continue sending additional commands.
#  The technique is: send the command, read until the next command prompt,
#  and then fetch/clear the internal receive buffer.

#  We're done, so shut it down..

#  Send an EOF.  This tells the server that no more data will
#  be sent on this channel.  The channel remains open, and
#  the SSH client may still receive output on this channel.
$success = $ssh->ChannelSendEof($channelNum);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Close the channel:
$success = $ssh->ChannelSendClose($channelNum);
if ($success != 1) {
    print $ssh->lastErrorText() . "\r\n";
    print $ssh->sessionLog() . "\r\n";
    exit;
}

#  Disconnect
$ssh->Disconnect();