Fri Jun 18 18:48:04 UTC 2004
On Jun 16, 2004, at 10:52 PM, Clive Cleland wrote: > Perhaps you could recognise the missing body in the application that > makes > the dccifd calls? The message passes through that application anyway, > so it > should be fairly straightforward to observe a missing body, and act > accordingly. Well, if we wanted to throw away (or otherwise consistently treat) all empty bodied messages I could do something about them in the 'connector' software I'm writing. But unless I reinvent DCC, or otherwise maintain a database of messages I've seen I wouldn't have a way to judge one empty message from another. I think the approach I'm going to suggest for handling these empty messages is to add a threshold for the Message-ID header. That will at least catch the truly identical (and rfc compliant ;-) messages. And On Jun 16, 2004, at 10:10 PM, Vernon Schryver wrote: >> From: Robert Thille <firstname.lastname@example.org> > > >> However, with the DCCIFD_REJECT_AT set at '10', sending 11 identical >> messages with empty bodies doesn't get any messages rejected. > > All three DCC body checksums require some minimal bits on which > to compute their sums. Right. I wasn't sure that Fuz1 and Fuz2 were just body checksums, or over the whole message (body and header). > >> I'm guessing that the problem is the '-t CMN' part, since the man page >> lists CMN as 'Body, Fuz1, Fuz2'. Do Fuz1 and Fuz2 cover the headers, >> or are they just 'fuzzy' checksums of the body? > > The Fuz1, Fuz2, and Body checksums are only of the SMTP body after > the blank line separating the headers from the rest. Useful information. > The best way to figure out what is going on is to turn on logging by > setting DCCM_LOG_AT or DCCIFD_LOG_AT to 0 in dcc_conf or turning on > "option log-all" in your main or a per-user whiteclnt file. The > resulting log files will have the checksums and their counts. I've got LOG_AT set to 1, and am getting log files which are helpful (though not so much in the case where they are all zero :-) > The idea of the DCC is to count targets of substantially identical > messages. "Substantially identical" gets boring near empty and > nearly empty messages such as "thanks" and "test". Well, you can have 'empty' messages which are SPAM and are exactly, or very nearly identical: spammer creates a single message, puts a URL in the subject, and does a rcpt-to to many users at many systems around the net. By the time DCC would see it, it would have a new 'Received' header, but would otherwise be identical. While not a large portion of SPAM I see, I can see those messages becoming 'interesting' if DCC widely deployed and does not address them. Also, I think the other engineers and manager types may see mail (spam) which appears empty, because they have HTML rendering disabled, or remote-image loading turned off, and so overestimate the amount of spam they receive with empty bodies. > I'll spare you the rant trigged by such familiar and destructive "QA" > noise. Why are so many QA groups rewarded only for shouting "BUG" and > never penalized for shoddy work? Well, in my case, I would defend our QA guy. He's just now been tasked with testing this and isn't fully familiar with DCC. My description of 'as configured it should reject the 11th+ of a series of identical messages' should have been amended to include 'non-empty'. > Why do most test suites contain > orders of magnitude more and worse bugs than the code they purport to > test? I think in most cases it's due to lack of resources, or the quality of the resources allocated to test vs. development. But these questions are rhetorical aren't they? :-) > Why do the pointy haired hire so many hopeless political hacks > as test czars? ... but I'm trying to spare you. To keep them company? To have someone they can relate to? Oops, there I go again, answering rhetorical questions... :-) BTW, I noticed that my first mail to the list got graylisted by the rhyolite.com email server. Is that something that happens to everyone, or is there some list I (or my IPs) have gotten onto that I don't want to be on? Thanks, Robert -- Robert Thille 7575 Meadowlark Dr.; Sebastopol, CA 95472 Home: 707.824.9753 Office/VOIP: 707.780.1560 Cell: 707.217.7544 Robert.Thille@rangat.org YIM:rthille http://www.rangat.org/rthille Cyclist, Mountain Biker, Freediver, Kayaker, Rock Climber, Hiker, Geek May your spirit dive deep the blue, where the fish are many and large!
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