SSH to a Cisco Switch - Processing "More" Responses

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Demonstrates connecting to a Cisco switch, entering privileged mode with the ena command, and running a command whose response is paged. Each page ends with --More-- and requires a SPACE character to request the next page.

Note: QuickShell allocates a PTY, which is what a network device console expects. The device presents an interactive prompt, and each command's output is read up to the next prompt.

use chilkat();

$success = 0;

#  This example requires the Chilkat API to have been previously unlocked.
#  See Global Unlock Sample for sample code.

#  Demonstrates connecting to a Cisco switch, entering privileged mode, and running a command
#  whose response is paged -- each page ends with "--More--" and requires a SPACE character to
#  request the next page.

$ssh = chilkat::CkSsh->new();

$port = 22;
$success = $ssh->Connect("172.16.16.100",$port);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  Normally you would not hard-code the password in source.  You should instead obtain it
#  from an interactive prompt, environment variable, or a secrets vault.
$password = "mySshPassword";

$success = $ssh->AuthenticatePw("mySshLogin",$password);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

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

#  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
#  which means no limit -- without it, this call waits forever if the received data never
#  contains a match.
$ssh->put_ReadTimeoutMs(15000);

$caseSensitive = 1;

#  In unprivileged mode the switch prompt ends with ">".
$success = $ssh->ChannelReceiveUntilMatch($channelNum,">","utf-8",$caseSensitive);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$received = $ssh->getReceivedText($channelNum,"utf-8");
if ($ssh->get_LastMethodSuccess() == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

print $received . "\r\n";

#  Send "ena" to enter privileged mode.  Cisco devices expect a bare CR to terminate a command.
$success = $ssh->ChannelSendString($channelNum,"ena\r","utf-8");
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$success = $ssh->ChannelReceiveUntilMatch($channelNum,"Password:","utf-8",$caseSensitive);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$received = $ssh->getReceivedText($channelNum,"utf-8");
if ($ssh->get_LastMethodSuccess() == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

print $received . "\r\n";

#  The enable password is separate from the login password, and likewise should come from a
#  secure source rather than being hard-coded.
$enablePassword = "myEnablePassword";
$success = $ssh->ChannelSendString($channelNum,$enablePassword,"utf-8");
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$success = $ssh->ChannelSendString($channelNum,"\r","utf-8");
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  In privileged mode the prompt ends with "#" instead of ">".
$success = $ssh->ChannelReceiveUntilMatch($channelNum,"#","utf-8",$caseSensitive);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

$received = $ssh->getReceivedText($channelNum,"utf-8");
if ($ssh->get_LastMethodSuccess() == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

print $received . "\r\n";

#  Run a command whose output is delivered a page at a time.
$success = $ssh->ChannelSendString($channelNum,"show running-config\r","utf-8");
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  Each read ends either at the device prompt (output complete) or at "--More--" (another page
#  is waiting).  Match the full prompt rather than a bare "#", because "#" also appears inside
#  configuration text and would match too early.
$saMatch = chilkat::CkStringArray->new();
$saMatch->Append("MySwitchName#");
$saMatch->Append("--More--");

$sbReceived = chilkat::CkStringBuilder->new();
$moreComing = 1;

while ($moreComing) {
    $success = $ssh->ChannelReceiveUntilMatchN($channelNum,$saMatch,"utf-8",$caseSensitive);
    if ($success == 0) {
        print $ssh->lastErrorText() . "\r\n";
        exit;
    }

    $sbReceived->Clear();
    $pageText = $ssh->getReceivedText($channelNum,"utf-8");
    if ($ssh->get_LastMethodSuccess() == 0) {
        print $ssh->lastErrorText() . "\r\n";
        exit;
    }

    $sbReceived->Append($pageText);
    print $pageText . "\r\n";

    #  If this page ended with "--More--", send a SPACE to request the next page.
    $moreComing = $sbReceived->Contains("--More--",$caseSensitive);
    if ($moreComing) {
        $success = $ssh->ChannelSendString($channelNum," ","utf-8");
        if ($success == 0) {
            print $ssh->lastErrorText() . "\r\n";
            exit;
        }

    }

}

$ssh->Disconnect();