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Lua Requires Chilkat v11.0.0+

POP3 over Multiple Hop SSH

Demonstrates how to read POP3 email (using TCP or TLS) tunneled through mulitple-hop SSH. The scheme looks like this:
Application => ServerSSH1 => ServerSSH2 => POP3Server

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Lua
local chilkat = require("chilkat")

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

local ssh1 = chilkat.Ssh.new()

-- Connect directly to the 1st SSH server.
local success = ssh1:connect("serverssh1.com", 22)
if not success then
    print(ssh1.last_error_text)
    return
end

-- Authenticate using login/password:
success = ssh1:authenticate_pw("ssh1Login", "ssh1Password")
if not success then
    print(ssh1.last_error_text)
    return
end

-- Connect through the 1st SSH connection to reach a 2nd SSH server.
-- Note: Any number of SSH connections may be simultaneously tunneled through a single
-- existing SSH connection.
local ssh2 = chilkat.Ssh.new()
success = ssh2:connect_through_ssh(ssh1, "serverssh2.com", 22)
if not success then
    print(ssh2.last_error_text)
    return
end

-- Authenticate with ssh2...
success = ssh2:authenticate_pw("ssh2Login", "ssh2Password")
if not success then
    print(ssh2.last_error_text)
    return
end

local mailman = chilkat.MailMan.new()

-- Tell the mailman object to connect to the POP3 server though the ssh2 tunnel (which itself is routed through ssh1).
-- The connection looks like this:  Application => ServerSSH1 => ServerSSH2 => POP3Server
success = mailman:use_ssh(ssh2)
if not success then
    print(mailman.last_error_text)
    return
end

-- Set the POP3 server's hostname
mailman.mail_host = "pop.example.com"

-- Set the POP3 login/password.
mailman.pop_username = "myLogin"
mailman.pop_password = "myPassword"

-- Establish the POP3 connection through the ssh2 tunnel.
success = mailman:pop3_begin_session()
if not success then
    print(mailman.last_error_text)
    return
end

-- Get the number of messages in the mailbox.
local numMessages = mailman:get_mailbox_count()

local email = chilkat.Email.new()
local i = 1
while i <= numMessages do
    -- Fetch by the message number (not by the UIDL)
    success = mailman:fetch_one(false, 0, i, email)
    if not success then
        print(mailman.last_error_text)
        return
    end

    print(email.from .. ": " .. email.subject .. "\n")

    i = i + 1
end

-- Close the connection with the POP3 server.  (This closes the tunnel through ssh2)
-- The connection with ssh2 is still alive, and may be used for more connections.
success = mailman:pop3_end_session()

-- Close the connection with ssh2.  (This closes the the tunnel through ssh1.)
-- The connection with ssh1 is still alive, and may be used for more connections.

ssh2:disconnect()

ssh1:disconnect()