(PowerShell) POP3 SSH Tunneling (Port Forwarding)

Demonstrates how to connect to a POP3 server through an SSH tunnel. Reads a POP3 mailbox and display the FROM and SUBJECT header fields of each email.

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

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

# The mailman object is used for receiving (POP3) 
# and sending (SMTP) email.
$mailman = New-Object Chilkat.MailMan

# The SSH hostname may be a hostname or an 
# IP address, such as "192.168.1.108".
# The port is typically 22 (the standard port for SSH).
$sshHostname = "sftp.example.com"
$sshPort = 22

# Connect to an SSH server and establish the SSH tunnel:
$success = $mailman.SshOpenTunnel($sshHostname,$sshPort)
if ($success -ne $true) {
    $($mailman.LastErrorText)
    exit
}

# Authenticate with the SSH server via a login/password
# or with a public key.
# This example demonstrates SSH password authentication.
# Note: This is not authenticating with the POP3 server, it is
# for authenticating with the SSH server, which is separate.
$success = $mailman.SshAuthenticatePw("ssh_login","ssh_password")
if ($success -ne $true) {
    $($mailman.LastErrorText)
    exit
}

# OK, the SSH tunnel is setup.  The mailman may
# be used exactly the same as usual, except all communications
# are now sent through the SSH tunnel.

# The SSH tunnel may be kept open for any number of 
# POP3 connections.  

# Set the POP3 server's hostname
$mailman.MailHost = "mail.my-pop3-server.com"

# Set the POP3 settings for your POP3 server:
$mailman.PopUsername = "pop3_login"
$mailman.PopPassword = "pop3_password"
$mailman.MailPort = 995
$mailman.PopSsl = $true

# Connect to the POP3 server through the already-established SSH tunnel:
$success = $mailman.Pop3BeginSession()
if ($success -ne $true) {
    $($mailman.LastErrorText)
    exit
}

# A visual inspection of the LastErrorText after
# a successful POP3 connection will confirm the SSH tunneling.
# Note: If the POP3 connection uses SSL/TLS, then the SSL/TLS 
# secure channel will be wrapped within the SSH tunnel.
$($mailman.LastErrorText)

# How many messages are in the POP3 inbox?
$numToDownload = $mailman.GetMailboxCount()
if ($numToDownload -gt 5) {
    $numToDownload = 5
}

if ($numToDownload -eq 0) {
    exit
}

# Download a max of 5 messages

for ($i = 1; $i -le $numToDownload; $i++) {
    $email = $mailman.FetchByMsgnum($i)
    if ($mailman.LastMethodSuccess -eq $false) {
        $($mailman.LastErrorText)
        exit
    }

    $($email.From)
    $($email.Subject)
    $("----")

}

# Close the connection with the POP3 server, leaving the SSH tunnel open for subsequent POP3 connections.
$success = $mailman.Pop3EndSession()
if ($success -ne $true) {
    $($mailman.LastErrorText)
    exit
}

# Try connecting to a different POP3 server through the same aleady setup SSH tunnel:
# Set the POP3 server's hostname
$mailman.MailHost = "mail.my-pop3-server2.com"

# Set the POP3 settings for your POP3 server:
$mailman.PopUsername = "pop3_login2"
$mailman.PopPassword = "pop3_password2"
$mailman.MailPort = 110
$mailman.PopSsl = $false

$success = $mailman.Pop3BeginSession()
if ($success -ne $true) {
    $($mailman.LastErrorText)
    exit
}

# Review the LastErrorText to see that the connection was made via the SSH tunnel:
$($mailman.LastErrorText)

$success = $mailman.Pop3EndSession()
if ($success -ne $true) {
    $($mailman.LastErrorText)
    exit
}

# Close the SSH tunnel.
$success = $mailman.SshCloseTunnel()
if ($success -ne $true) {
    $($mailman.LastErrorText)
    exit
}