gpg-lacre/test/relay.py

83 lines
1.8 KiB
Python

#!/usr/local/bin/python2
#
# This quick-and-dirty script supports only the happy case of SMTP session,
# i.e. what gpg-mailgate/gpg-lacre needs to deliver encrypted email.
#
# It listens on the port given as the only command-line argument and consumes a
# message, then prints it to standard output. The goal is to be able to
# compare that output with expected clear-text or encrypted message body.
#
import sys
import socket
EXIT_UNAVAILABLE = 1
BUFFER_SIZE = 4096
EOM = "\r\n.\r\n"
LAST_LINE = -3
def welcome(msg):
return "220 %s\r\n" % (msg)
def ok(msg = "OK"):
return "250 %s\r\n" % (msg)
def bye():
return "251 Bye"
def provide_message():
return "354 Enter a message, ending it with a '.' on a line by itself\r\n"
def receive_and_confirm(session):
session.recv(BUFFER_SIZE)
session.sendall(ok())
def serve(port):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
s.bind(('', port))
s.listen(1)
except socket.error as e:
print("Cannot connect", e)
sys.exit(EXIT_UNAVAILABLE)
(conn, addr) = s.accept()
conn.sendall(welcome("TEST SERVER"))
receive_and_confirm(conn) # Ignore HELO/EHLO
receive_and_confirm(conn) # Ignore sender address
receive_and_confirm(conn) # Ignore recipient address
data = conn.recv(BUFFER_SIZE)
conn.sendall(provide_message())
# Consume until we get <CR><LF>.<CR><LF>, the end-of-message marker.
message = ''
while not message.endswith(EOM):
message += conn.recv(BUFFER_SIZE)
conn.sendall(ok("OK, id=test"))
conn.recv(BUFFER_SIZE)
conn.sendall(bye())
conn.close()
# Trim EOM marker as we're only interested in the message body.
return message[:-len(EOM)]
def error(msg):
print("ERROR: %s" % (msg))
sys.exit(1)
if len(sys.argv) < 2:
error("Usage: relay.py PORT_NUMBER")
port = int(sys.argv[1])
body = serve(port)
print(body)