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Chilkat2-Python

SMTP over Multiple Hop SSH

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

The ConnectThroughSsh and UseSsh methods are added in Chilkat version 9.5.0.55 to accomplish this task.

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Chilkat2-Python
import sys
import chilkat2

success = False

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

ssh1 = chilkat2.Ssh()

# Connect directly to the 1st SSH server.
success = ssh1.Connect("serverssh1.com",22)
if (success != True):
    print(ssh1.LastErrorText)
    sys.exit()

# Authenticate using login/password:
success = ssh1.AuthenticatePw("ssh1Login","ssh1Password")
if (success != True):
    print(ssh1.LastErrorText)
    sys.exit()

# 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.
ssh2 = chilkat2.Ssh()
success = ssh2.ConnectThroughSsh(ssh1,"serverssh2.com",22)
if (success != True):
    print(ssh2.LastErrorText)
    sys.exit()

# Authenticate with ssh2...
success = ssh2.AuthenticatePw("ssh2Login","ssh2Password")
if (success != True):
    print(ssh2.LastErrorText)
    sys.exit()

mailman = chilkat2.MailMan()

# Tell the mailman object to connect to the SMTP server though the ssh2 tunnel (which itself is routed through ssh1).
# The connection looks like this:  Application => ServerSSH1 => ServerSSH2 => SMTPServer
success = mailman.UseSsh(ssh2)
if (success != True):
    print(mailman.LastErrorText)
    sys.exit()

# Set the SMTP server.
mailman.SmtpHost = "smtp.someserver.com"

# Set the SMTP login/password (if required)
mailman.SmtpUsername = "myUsername"
mailman.SmtpPassword = "myPassword"

# Create a new email object
email = chilkat2.Email()

email.Subject = "This is a test"
email.Body = "This is a test"
email.From = "Chilkat Support <support@chilkatsoft.com>"
success = email.AddTo("Chilkat Admin","admin@chilkatsoft.com")

success = mailman.SendEmail(email)
if (success != True):
    print(mailman.LastErrorText)
    sys.exit()

# Close the connection with the server.  This closes the tunnel through ssh2.
success = mailman.CloseSmtpConnection()
if (success != True):
    print("Connection to SMTP server not closed cleanly.")

print("Mail Sent!")

# 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()