PyBitmessage-2021-04-27/src/class_smtpServer.py
2020-01-15 16:17:26 +05:30

215 lines
7.1 KiB
Python

"""
SMTP server thread
"""
import asyncore
import base64
import email
import logging
import re
import signal
import smtpd
import threading
import time
from email.header import decode_header
from email.parser import Parser
import queues
from addresses import decodeAddress
from bmconfigparser import BMConfigParser
from helper_ackPayload import genAckPayload
from helper_sql import sqlExecute
from network.threads import StoppableThread
from version import softwareVersion
SMTPDOMAIN = "bmaddr.lan"
LISTENPORT = 8425
logger = logging.getLogger('default')
# pylint: disable=attribute-defined-outside-init
class smtpServerChannel(smtpd.SMTPChannel):
"""Asyncore channel for SMTP protocol (server)"""
def smtp_EHLO(self, arg):
"""Process an EHLO"""
if not arg:
self.push('501 Syntax: HELO hostname')
return
self.push('250-PyBitmessage %s' % softwareVersion)
self.push('250 AUTH PLAIN')
def smtp_AUTH(self, arg):
"""Process AUTH"""
if not arg or arg[0:5] not in ["PLAIN"]:
self.push('501 Syntax: AUTH PLAIN')
return
authstring = arg[6:]
try:
decoded = base64.b64decode(authstring)
correctauth = "\x00" + BMConfigParser().safeGet(
"bitmessagesettings", "smtpdusername", "") + "\x00" + BMConfigParser().safeGet(
"bitmessagesettings", "smtpdpassword", "")
logger.debug('authstring: %s / %s', correctauth, decoded)
if correctauth == decoded:
self.auth = True
self.push('235 2.7.0 Authentication successful')
else:
raise Exception("Auth fail")
except:
self.push('501 Authentication fail')
def smtp_DATA(self, arg):
"""Process DATA"""
if not hasattr(self, "auth") or not self.auth:
self.push('530 Authentication required')
return
smtpd.SMTPChannel.smtp_DATA(self, arg)
class smtpServerPyBitmessage(smtpd.SMTPServer):
"""Asyncore SMTP server class"""
def handle_accept(self):
"""Accept a connection"""
pair = self.accept()
if pair is not None:
conn, addr = pair
# print >> DEBUGSTREAM, 'Incoming connection from %s' % repr(addr)
self.channel = smtpServerChannel(self, conn, addr)
def send(self, fromAddress, toAddress, subject, message):
"""Send a bitmessage"""
# pylint: disable=arguments-differ
streamNumber, ripe = decodeAddress(toAddress)[2:]
stealthLevel = BMConfigParser().safeGetInt('bitmessagesettings', 'ackstealthlevel')
ackdata = genAckPayload(streamNumber, stealthLevel)
sqlExecute(
'''INSERT INTO sent VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)''',
'',
toAddress,
ripe,
fromAddress,
subject,
message,
ackdata,
int(time.time()), # sentTime (this will never change)
int(time.time()), # lastActionTime
0, # sleepTill time. This will get set when the POW gets done.
'msgqueued',
0, # retryNumber
'sent', # folder
2, # encodingtype
# not necessary to have a TTL higher than 2 days
min(BMConfigParser().getint('bitmessagesettings', 'ttl'), 86400 * 2)
)
queues.workerQueue.put(('sendmessage', toAddress))
def decode_header(self, hdr):
"""Email header decoding"""
ret = []
for h in decode_header(self.msg_headers[hdr]):
if h[1]:
ret.append(unicode(h[0], h[1]))
else:
ret.append(h[0].decode("utf-8", errors='replace'))
return ret
def process_message(self, peer, mailfrom, rcpttos, data):
"""Process an email"""
# pylint: disable=too-many-locals, too-many-branches
# print 'Receiving message from:', peer
p = re.compile(".*<([^>]+)>")
if not hasattr(self.channel, "auth") or not self.channel.auth:
logger.error('Missing or invalid auth')
return
try:
self.msg_headers = Parser().parsestr(data)
except:
logger.error('Invalid headers')
return
try:
sender, domain = p.sub(r'\1', mailfrom).split("@")
if domain != SMTPDOMAIN:
raise Exception("Bad domain %s" % domain)
if sender not in BMConfigParser().addresses():
raise Exception("Nonexisting user %s" % sender)
except Exception as err:
logger.debug('Bad envelope from %s: %r', mailfrom, err)
msg_from = self.decode_header("from")
try:
msg_from = p.sub(r'\1', self.decode_header("from")[0])
sender, domain = msg_from.split("@")
if domain != SMTPDOMAIN:
raise Exception("Bad domain %s" % domain)
if sender not in BMConfigParser().addresses():
raise Exception("Nonexisting user %s" % sender)
except Exception as err:
logger.error('Bad headers from %s: %r', msg_from, err)
return
try:
msg_subject = self.decode_header('subject')[0]
except:
msg_subject = "Subject missing..."
msg_tmp = email.message_from_string(data)
body = u''
for part in msg_tmp.walk():
if part and part.get_content_type() == "text/plain":
body += part.get_payload(decode=1).decode(part.get_content_charset('utf-8'), errors='replace')
for to in rcpttos:
try:
rcpt, domain = p.sub(r'\1', to).split("@")
if domain != SMTPDOMAIN:
raise Exception("Bad domain %s" % domain)
logger.debug(
'Sending %s to %s about %s', sender, rcpt, msg_subject)
self.send(sender, rcpt, msg_subject, body)
logger.info('Relayed %s to %s', sender, rcpt)
except Exception as err:
logger.error('Bad to %s: %r', to, err)
continue
return
class smtpServer(StoppableThread):
"""SMTP server thread"""
def __init__(self, _=None):
super(smtpServer, self).__init__(name="smtpServerThread")
self.server = smtpServerPyBitmessage(('127.0.0.1', LISTENPORT), None)
def stopThread(self):
super(smtpServer, self).stopThread()
self.server.close()
return
def run(self):
asyncore.loop(1)
def signals(_, __):
"""Signal handler"""
logger.warning('Got signal, terminating')
for thread in threading.enumerate():
if thread.isAlive() and isinstance(thread, StoppableThread):
thread.stopThread()
def runServer():
"""Run SMTP server as a standalone python process"""
logger.warning('Running SMTPd thread')
smtpThread = smtpServer()
smtpThread.start()
signal.signal(signal.SIGINT, signals)
signal.signal(signal.SIGTERM, signals)
logger.warning('Processing')
smtpThread.join()
logger.warning('The end')
if __name__ == "__main__":
runServer()