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Spam Blocking Engine for OpenBSD

Posted by michael on from the two-scoops-white-rice dept.

mkeke writes "In a post over at OpenBSD Journal, Theo states that he has written a spam blocker that works with pf and Spews. It looks darn cool :)"

6 of 278 comments (clear)

  1. Spews = /m\ by joeszilagyi · · Score: 5, Insightful

    Why even bother with Spews? Why not Spamcop, who doesn't block half the planet?

    --
    Dude, where's my packet?
    1. Re:Spews = /m\ by Just+Some+Guy · · Score: 5, Insightful
      Your company was paying that ISP. Thus it was also supporting spam.

      I understand the principle involved, and admit a fair bit of sympathy for that point of view. However, for some of us, switching ISPs isn't a luxury we have. I live in a small Midwest town. My options are:

      • DSL/wireless via the local dominant ISP
      • DSL via MSN
      • Cable modem
      • Dialup via one of those "unlimited access for only $6.95!!!!" companies
      Out of that list, the first option is the only one viable for hosting servers, since the rest either block service ports, have onerous TOS contracts, or just aren't serious connections.

      Say that I discover that the local ISP (which has probably a 98% market share here) has some customers with open relays. What do I do? Buy a T1 and contract with Qwest, or get out of online business altogether?

      In practicality, I don't have the option to switch, regardless of my ISPs policies.

      Fortunately, the provider is run by a great set of people, and employees several real system administrators, so I don't really have to worry about this hypothetical problem. That's a Good Thing, because I'm pretty well stuck where I am.

      --
      Dewey, what part of this looks like authorities should be involved?
  2. SPEWS is necessary & effective at hurting spam by Charles+Dodgeson · · Score: 5, Insightful
    Time and again we see case after case of some provider that
    1. Let some customers spam
    2. ignored abuse complaints
    3. did nothing while when that particular spammer's IP was listed.
    4. Only took action against a spammer when the SPEWS listing expanded to include non-spamming customers
    5. Whinged that SPEWS was unfair and not the right way to do things
    Every day SPEWS proves itself necessary and effective at getting otherwise unwilling providers to remove their spammers. Note that SPEWS uses an escalation process. The provider has to ignore complaints for a while to have the IP range expanded to include non-spammers

    If you can suggest something that is half as effective at raising the cost for spammers as SPEWS, please suggest it. SPEWS forces providers to decide whether they want to host exclusively spammers or host exclusively non-spammers.

    But if your goal is merely to filter spam (making life easier for the spammers) then you are right. SPEWS is not the way to do that.

    --
    Prime numbers are exactly what Alan Greenspan says they are -S. Minsky
  3. I'm Disappointed by TerryAtWork · · Score: 4, Insightful

    I remember when I applied for a Mead mailing list and got a nasty letter back saying 'your SPAM has been rejected!' just because I sent it from a Rogers.com address, so I know what it's like to be blacklisted like in SPEWS, and it sucks. That's not the way to do it.

    Also, this new spam program retaliates and the law is very nasty about vigilantism and retaliation, perhaps because it threatens their monopoly. I don't want to see a spammer WIN in court, do you?

    Also, program like popfile doe a great job of removing spam.

    My advice is to forget kicking the spammers ass and just make their work vanish down a black hole like it will WHEN BAYESIAN TECHNIQUES ARE USED AT THE ISP END hint hint...

    --
    It's Christmas everyday with BitTorrent.
  4. Re:SPEWS is necessary & effective at hurting s by jamie · · Score: 5, Insightful
    "If you can suggest something that is half as effective at raising the cost for spammers as SPEWS, please suggest it. SPEWS forces providers to decide whether they want to host exclusively spammers or host exclusively non-spammers."

    First of all, I don't think most network administrators -- or their bosses -- know what they're getting into when they use Spews to police their network. If you are an admin who signs your company up for it, be prepared to have this conversation:

    Boss: Hey, can you check to see if there's some kind of network trouble. I haven't gotten a reply email from a client in three days.

    You: (after checking) Ah, that mail server is spam-friendly, we reject their mail.

    Boss: (confused) They're not a spammer, they're our best client.

    You: No, but they buy bandwidth from someone who buys bandwidth from someone who...

    Boss: What?

    You: We're using SPEWS, which is the most effective tool at stopping spam around the world! It forces providers to decide whether...

    Boss: I don't give a damn, you work for me, not people around the world. Your job is to make the email work, not be a do-gooder. You may have cost this company a contract. Now get the damn mail working and tell me how many times you bounced my client's mail so I can decide whether you still have a job.

    And -- you think Spews is effective? After being put on their list I had a grand total of one person unable to receive my mail. I have a dozen other people using my server to send and receive mail to hundreds of people, and according to my logs, among all of us, the sum total of people who couldn't get our email was two. That's the most pitiful boycott I've ever seen.

  5. Re:Good concept - quality of execution pending by Dunark · · Score: 4, Insightful

    I don't see the hypocrisy. If a neighbor of mine allows people to cross his property so they can dump garbage on my property, where do I get the obligation to accept the garbage? What's wrong with me putting up a fence and letting the garbage pile up on his side?

    If someone wishes to run an open relay and be a conduit for spam, why should he be granted immunity from consequences?