Perl

SSH Tunnel Per-Client Logging and Client Identifier

Demonstrates the ClientLogDir and ClientIdentifier properties. When ClientLogDir is set, a separate log file is created for each tunnel client; ClientIdentifier is the SSH client-identification string sent during the handshake.

Note: The log paths are relative to the application's current working directory. Absolute paths may also be used.

Background: When many clients share one tunnel, a single combined log is hard to follow, so ClientLogDir gives each connection its own file — the fastest way to diagnose one misbehaving client. ClientIdentifier sets the version string the server sees; overriding the default is occasionally needed for compatibility with servers that key behavior off the client identification, or simply to label your application in server logs.

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Perl

use chilkat();

$success = 0;

#  Demonstrates the SshTunnel per-client logging properties ClientLogDir and ClientIdentifier.

$tunnel = chilkat::CkSshTunnel->new();

#  When ClientLogDir is set, a separate log file is created for each tunnel client in this
#  directory, which is useful for troubleshooting individual connections.
$tunnel->put_ClientLogDir("qa_output/client_logs");

#  The SSH client-identification string sent to the SSH server during the handshake.
$tunnel->put_ClientIdentifier("SSH-2.0-MyTunnelApp_1.0");

$tunnel->put_DestHostname("db.internal.example.com");
$tunnel->put_DestPort(5432);

$sshPort = 22;
$success = $tunnel->Connect("ssh.example.com",$sshPort);
if ($success == 0) {
    print $tunnel->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 = $tunnel->AuthenticatePw("mySshLogin",$password);
if ($success == 0) {
    print $tunnel->lastErrorText() . "\r\n";
    exit;
}

$listenPort = 1080;
$success = $tunnel->BeginAccepting($listenPort);
if ($success == 0) {
    print $tunnel->lastErrorText() . "\r\n";
    exit;
}

print "Tunnel running; each client is logged in " . $tunnel->clientLogDir() . "\r\n";

$waitForThreadExit = 1;
$success = $tunnel->CloseTunnel($waitForThreadExit);
if ($success == 0) {
    print $tunnel->lastErrorText() . "\r\n";
    exit;
}