Tcl

Use an Existing Socket SSH Tunnel

Demonstrates the Chilkat MailMan.UseSshTunnel method, which configures MailMan to use an existing SSH tunnel provided by a Socket object for its SMTP and POP3 connections. This example opens and authenticates a tunnel on a Socket, hands it to MailMan, and then verifies an SMTP login through it.

Background: Sharing one already-established SSH tunnel across objects avoids opening (and authenticating) a separate SSH connection for every component that needs to reach the remote network. Here the tunnel lives on a Socket object, which MailMan then routes its SMTP/POP3 traffic through. It is the Socket-based sibling of UseSsh, which shares an Ssh object instead.

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Tcl


load ./chilkat.dll

set success 0

#  Demonstrates the MailMan.UseSshTunnel method, which configures MailMan to use an existing
#  SSH tunnel provided by a Socket object for its SMTP and POP3 connections.

#  Open and authenticate the SSH tunnel using a Socket object.
set sshTunnel [new_CkSocket]

set success [CkSocket_SshOpenTunnel $sshTunnel "ssh.example.com" 22]
if {$success == 0} then {
    puts [CkSocket_lastErrorText $sshTunnel]
    delete_CkSocket $sshTunnel
    exit
}

set success [CkSocket_SshAuthenticatePw $sshTunnel "sshUser" "sshPassword"]
if {$success == 0} then {
    puts [CkSocket_lastErrorText $sshTunnel]
    delete_CkSocket $sshTunnel
    exit
}

set mailman [new_CkMailMan]

#  Configure the SMTP server connection.  These connections will travel through the tunnel.
CkMailMan_put_SmtpHost $mailman "smtp.example.com"
CkMailMan_put_SmtpPort $mailman 465
CkMailMan_put_SmtpSsl $mailman 1
CkMailMan_put_SmtpUsername $mailman "user@example.com"
CkMailMan_put_SmtpPassword $mailman "myPassword"

#  Tell MailMan to route its connections through the existing tunnel.
set success [CkMailMan_UseSshTunnel $mailman $sshTunnel]
if {$success == 0} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkSocket $sshTunnel
    delete_CkMailMan $mailman
    exit
}

#  SMTP operations now travel through the shared SSH tunnel.
set success [CkMailMan_VerifySmtpLogin $mailman]
if {$success == 0} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkSocket $sshTunnel
    delete_CkMailMan $mailman
    exit
}

puts "Authenticated with the SMTP server through the SSH tunnel."

delete_CkSocket $sshTunnel
delete_CkMailMan $mailman