Kamaelia Grey

Michael Sparks , [email protected]

Kamaelia Grey

Relevant disclosure?- Kamaelia came out of my day work @ BBC Research- Kamaelia grey came out of my personal frustration, and has nothing to do with the BBC :-)

Drastic Spam reduction through Greylisting

Greylisting made easy through natural concurrency

Natural concurrency made easy through Kamaelia

... since that's what Kamaelia is for

Kamaelia Grey

Problem?

Spam was getting ridiculous

One weekend the number of emails to home address topped 1000

96% was spam

4% wasn't, but was mainly mailing lists

Around 1% interesting

Next to impossible to find

NB: I run my own mail server :-)

Kamaelia

Day project at the BBC since 2003

Toolkit for making concurrency easy to work with in the context of

Networking (servers/clients)

Multimedia

TV

Pretty much anything

Designed to make writing servers fast, scalable & reliable

Greylisting 1

Client connects, wants to send us mail

Have we let their email through before?

YES!

I CAN HAZACCEPT ALL UR EMAIL

Greylisting

Client connects, wants to send us mail

Have we seen them before?

NO!

KTHXBYE

Greylisting

Client comes back after KTHXBYE

Is it a resend of the same message after a reasonable delay?

Greylisting



YES!

I CAN HAZACCEPT ALL UR EMAIL

Greylisting



NO!

KTHXBYE

Where?

Here!

Requirements

Python 2.3 onwards

Must run your own mail server already

Requires Kamaelia, but the tar ball includes that.

I developed it under Linux

I've got it deployed on Mac OS X

Mail serving

UNTRUSTEDINTERNET

Mail serving

UNTRUSTEDINTERNETMAILSERVER25

Mail serving

UNTRUSTEDINTERNETMAILSERVER25

Mail serving

UNTRUSTEDINTERNETMAILSERVER

25

Greylisting


8025

Greylisting


8025KamGrey25

Greylisting


8025KamGrey25

Installing

Grab the code & install

python setup.py install

Configure

edit /etc/greylist.conf

then run

/etc/init.d/kamaeliagrey start

I actually just use

App/runGreylister.sh

Basic config

port = 25servername = mail.cerenity.orgserverid = Kamaelia-SMTP 1.0smtp_ip = 192.168.2.9smtp_port = 8025inactivity_timeout = 60greylist_log = /var/log/greylist.loggreylist_debuglog = /var/log/greylist-debug.logattempters_db = /var/spool/attempters.dbmgreylisted_db = /var/spool/greylisted.dbm

Local config

allowed_senders: 127.0.0.1

allowed_sender_nets: 192.168.2

allowed_domains: private.thwackety.com thwackety.com thwackety.net yeoldeclue.com michaelsparks.info lansdowneresidents.org polinasparks.com pixienest.com kamaelia.org owiki.org cerenity.org

Exceptions

# Standard triples which always allows delivery to domains we consider# accepting for.## Format:# IP address, mail-from id, recipient id#whitelisted_triples: 213.38.186.202

Exceptions

# Some non-standard triples for which we always allow delivery# to domains we consider accepting for.# Format:# claimed sender name, IP prefix, recipient#whitelisted_nonstandard_triples: listmail.artsfb.org.uk 62.73.155.19 mx-out.facebook.com 204.15.20 mx-out.facebook.com 204.15.20 fallbackmx-out.facebook.com 204.15.20 fallbackmx-out.facebook.com 204.15.20

Logging?

Standard log:/var/log/greylist.log

20071106172215.940 | dsl88.241-20782.ttnet.net.tr | 88.241.81.46 | | | DEFERRED |
20071106172231.269 | dsl88.241-20782.ttnet.net.tr | 88.241.81.46 | | | DEFERRED |20071106172238.610 | 34-148.privatnet.cz | 88.146.148.34 | | | DEFERRED |20071106172244.333 | dsl88.241-20782.ttnet.net.tr | 88.241.81.46 | | | DEFERRED |20071106172247.885 | mta410.k.cheetahmail.com | 208.49.63.136 | | | ACCEPTED |

Logging?

Debug log:/var/log/greylist.log250 OK250 ACCEPTED451 4.7.1 Please try again later220 mail.cerenity.org ESMTP Kamaelia-SMTP 1.0 Tue Nov 6 17:26:01 2007500 Command Not Recognised250 mail.cerenity.org Hello lse 89.252.24.7250 OKNote this is what's being sent over SMTP

But also...

Debug log:/var/log/greylist-debug.log

*debug* THREADS['Kamaelia.Chassis.Pipeline.Pipeline_7', 'Kamaelia.Internet.Selector.Selector_11', '__main__.GreylistServer_8', '__main__.PeriodicWakeup_5', '__main__.TCPS_10', '__main__.WakeableIntrospector_6']

Note this says the current internal components running

Internals


['Kamaelia.Chassis.Pipeline.Pipeline_7', 'Kamaelia.Internet.Selector.Selector_11',
'__main__.GreylistServer_8',
'__main__.PeriodicWakeup_5',
'__main__.TCPS_10',
'__main__.WakeableIntrospector_6']


Internals


Kamaelia.Internet.Selector.Selector_11 wakes system on network events
__main__.TCPS_10 sits inside and handles listening for
'__main__.GreylistServer_8 A configured network server
Kamaelia.Chassis.Pipeline.Pipeline_7 For debugging'__main__.PeriodicWakeup_5 For debugging
'__main__.WakeableIntrospector_6 For debugging


No connection!

TCPServerGreylistServerSelector

New connection!

TCPServerGreylistServerSelectorConnectedSocketAdapterGreyListingPolicy

More connections!

TCPServerGreylistServerSelectorConnectedSocketAdapterGreyListingPolicy

ConnectedSocketAdapterGreyListingPolicy



Accepted!

GreyListingPolicyTCPClientMAILSERVER8025

ConnectedSocketAdapter

Rejected!


Greylisting

GreyListingPolicyConcreteMailHandlerMailHandlerISAISA

Internals

The following pages are intended as a walk through of the key highlights of the code-base. It skips the body of the code since that's best looked at by scrolling through code and chatting rather than dumping into slides.

In a presentation its easy to say this, and then after going through slides giving road pointers go through the code.

Presentation files are a little more limited.

The code referred to is here: http://tinyurl.com/2sbjxl

Internals

class MailHandler(Axon.Component.component): logfile = "greylist.log" debuglogfile = "greylist-debug.log"

Internals

class MailHandler(Axon.Component.component): def __init__(self,**argd): def logging_recv_connection(self): def getline(self): def handleCommand(self,command): def noteToLog(self, line): def noteToDebugLog(self, line): def netPrint(self, *args): def lastline(self): def main(self):

Internals

class ConcreteMailHandler(MailHandler): Inboxes = { "inbox" : "Data from the client connecting to the server comes in here", "control" : "Shutdown & control messages regarding client side socket handling", "tcp_inbox" : "This is where we get respones from the real SMTP server", "tcp_control" : "This is where we get shutdown information from the real SMTP server", } Outboxes = { "outbox" : "Data sent here goes back the the client connecting to the server", "signal" : "Shutdown & control messages regarding client side socket handling", "tcp_outbox" : "Data sent here is sent to the real SMTP server", "tcp_signal" : "We send messages here to shutdown the connection to the real SMTP connection", } peer = "*** UNDEFINED ***" peerport = "*** UNDEFINED ***" local = "*** UNDEFINED ***" localport = "*** UNDEFINED ***" servername = "Testing.server.local" serverid = "MPS SMTP 1.0" smtp_ip = "192.168.2.9" smtp_port = 25

Internals

class ConcreteMailHandler(MailHandler): def connectToRealSMTPServer(self): def __init__(self, **argv): def error(self, message): def RelayError(self): def handleConnect(self): def handleEhlo(self,command): def handleHelo(self,command): def handleHelp(self,command): def handleVrfy(self,command): def handleRset(self,command): def handleNoop(self,command): def handleMail(self,command): def handleRcpt(self,command): def handleData(self, command): def handleQuit(self,command): def shouldWeAcceptMail(self): return False # Default policy - don't accept any email def deferMail(self): def acceptMail(self): def getline_fromsmtpserver(self): def handleDisconnect(self):

Internals

class GreyListingPolicy(ConcreteMailHandler): allowed_senders = [] allowed_sender_nets = [] allowed_domains = [ ]

Internals

class GreyListingPolicy(ConcreteMailHandler): (continued) def shouldWeAcceptMail(self): def sentFromAllowedIPAddress(self): def sentFromAllowedNetwork(self): def sentToADomainWeForwardFor(self): def isGreylisted(self, recipient): def whiteListed(self, recipient): def logResult(self):

Internals

class GreylistServer(MoreComplexServer): logfile = config["greylist_log"] debuglogfile = config["greylist_debuglog"] socketOptions=(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) port = config["port"] class TCPS(TCPServer): CSA = NoActivityTimeout(ConnectedSocketAdapter,
timeout=config["inactivity_timeout"], debug=False)....

Internals

class GreylistServer(MoreComplexServer): (continued)# ... class protocol(GreyListingPolicy): servername = config["servername"] serverid = config["serverid"] smtp_ip = config["smtp_ip"] smtp_port = config["smtp_port"] allowed_senders = config["allowed_senders"] allowed_sender_nets = config["allowed_sender_nets"] allowed_domains = config["allowed_domains"] whitelisted_triples = config["whitelisted_triples"] whitelisted_nonstandard_triples =
config["whitelisted_nonstandard_triples"]

And that...

Saves me having to wade through now literally tens of thousands of spams over the past two months:

# grep DEFERRED /var/log/greylist.log |wc -l 73798

Time to write?

2 days start to finish including protocol

Bug fixes ~1-2 days tops

Questions?

Thank you :-)I hope it's useful to you :)

Click to edit the title text format

Click to edit the outline text format

Second Outline Level

Third Outline Level

Fourth Outline Level

Fifth Outline Level

Sixth Outline Level

Seventh Outline Level

Eighth Outline Level

Ninth Outline Level

http://kamaelia.sourceforge.net/KamaeliaGrey

Kamaelia Grey

Technology

Transcript of Kamaelia Grey