Jump to content

Annoying bug in Spamcop HTTP POST handling


iixii

Recommended Posts

Hi,

when submitting spam through the html form, my browser (Opera) sends the POST request with the HTTP header item "Expect: 100-continue" if the spam is bigger than 10 KB. This is a way of checking that the receiving server really wants so much data, instead of potentially sending it in vain. Quoting RFC 2616:

- Upon receiving a request which includes an Expect request-header field with the "100-continue" expectation, an origin server MUST either respond with 100 (Continue) status and continue to read from the input stream, or respond with a final status code. The origin server MUST NOT wait for the request body before sending the 100 (Continue) response.

The latter is precisely what spamcop does: It responds nothing, and after a certain delay the browser assumes that the server doesn't support 100-continue and sends the data, and then spamcop sends the 100 (Continue) response, naturally confusing the browser.

Please fix this. If it's difficult to get the "100-continue" sent at the right time, i.e. before any data arrives, a simpler fix would be to just not send it at all.

Link to comment
Share on other sites

And yet another situation ..... there are two Topics already underway dealing with (alleged) problems with dealing with some Akamai servers. The point being, you are probably not talking directly to www.spamcop.net hardware .. rather going through some Akamai server somewhere. If you take a look at those other Topics, you'll find that I'm already waiting for a response from them ....

On the other hand, there are other users that use an Opera browser and say things work fine. So we start some of the same confusion as seen in those other referenced Topics. Back to the additional datum of where you are connecting from, where your "local Akamaized server" is sitting at, and what kind of connectivity issues might be involved right there, and if there is a configuration setting that might be different on your system .... (things are not always as simple as they seem)

Link to comment
Share on other sites

And yet another situation ..... there are two Topics already underway dealing with (alleged) problems with dealing with some Akamai servers.  The point being, you are probably not talking directly to www.spamcop.net hardware .. rather going through some Akamai server somewhere.

Dang, you're right.

If you take a look at those other Topics, you'll find that I'm already waiting for a response from them ....

Oh dear, I don't have high hopes...

On the other hand, there are other users that use an Opera browser and say things work fine.

This only happens when submitting spam that is bigger than 10 KB through the HTTP-form. Probably the other Opera users just don't report spam that way.

where you are connecting from

Schwerte, Germany.

where your "local Akamaized server" is sitting at

212.187.169.229, in Frankfurt

and what kind of connectivity issues might be involved right there

None, there are no problems whatsoever connecting to the server, it's just an HTTP protocol thing.

and if there is a configuration setting that might be different on your system ....

Nope, the server mishandles "Expect: 100-continue", regardless of any other headers, and this is definitely a server bug.

In this case, it would be interesting how Akamai forwards the traffic to Spamcop, which ultimately processes it and creates the responses. If it acts as an HTTP proxy, then it's Akamai's fault. If it forwards traffic on the TCP level, then it's a Spamcop bug. Anyone know more about that? Akamai's site is spectacularly uninformative when it comes to technical issues. Just marketing crap, blarg!

Link to comment
Share on other sites

This only happens when submitting spam that is bigger than 10 KB through the HTTP-form. Probably the other Opera users just don't report spam that way.

23027[/snapback]

I use Opera 6.06, and haven't noticed the specific problem you see, but I haven't been checking Ethereal logs either. If you could describe the symptoms I might be able to confirm. "Confuses the browser" is vague.

I do occasionally have tabs that get stuck; it can happen after any request to SpamCop for a page. The symptom is that the page will just sit waiting forever. The reload symbol is active, the status bar has the timer counting how long it's been waiting. The longest I've let one run is 10 minutes. Hitting reload fixes it right up. Usually when I hit the stop button part of the page has been loaded, and it seems that usually the .css sheet is missing.

It only happens once in a while, which might correspond to the "only emails over 10Kb" threshold or might not; I haven't been paying attention. I'll leave Ethereal up tomorrow and see though.

Actually, I think I am probably seeing something else. This "stuckness" can happen on any SpamCop page, and often happens when retrieving the "Send Reports" page, which is outside the scope of your problem.

I'd just put mine down to network/SpamCop load.

...Stu

Link to comment
Share on other sites

I use Opera 6.06, and haven't noticed the specific problem you see, but I haven't been checking Ethereal logs either. If you could describe the symptoms I might be able to confirm. "Confuses the browser" is vague.

Well, after Opera has sent the whole form content, the server replies:

HTTP/1.1 100 Continue

Expires: Sat, 15 Jan 2005 08:43:29 GMT

Cache-Control: max-age=0, no-cache, no-store

Pragma: no-cache

Date: Sat, 15 Jan 2005 08:43:29 GMT

Transfer-Encoding: chunked

Connection: keep-alive

Connection: Transfer-Encoding

000001C2

HTTP/1.1 100 Continue

HTTP/1.1 100 Continue

<snipped a bunch of further HTTP/1.1 100 Continue lines>

Naturally, Opera thinks this is the reply to the form post, and just displays a text page with the HTTP/1.1 100 Continue lines.

However, because the 100-continue didn't arrive when it should, Opera concludes that the server doesn't support expect-continue and will not send it on subsequent requests. Thus the error will only occur once per session.

I do occasionally have tabs that get stuck; <...> It only happens once in a while, which might correspond to the "only emails over 10Kb" threshold or might not; I haven't been paying attention. I'll leave Ethereal up tomorrow and see though.

I haven't used Opera 6 for quite a while, but I just checked the source and can confirm that it handles http-continue exactly like Opera 7. Thus, it should also exhibit the problem.

Link to comment
Share on other sites

Well, after Opera has sent the whole form content, the server replies:

HTTP/1.1 100 Continue

<snipped a bunch of further HTTP/1.1 100 Continue lines>

Naturally, Opera thinks this is the reply to the form post, and just displays a text page with the HTTP/1.1 100 Continue lines.

Ok, that I haven't seen.

However, because the 100-continue didn't arrive when it should, Opera concludes that the server doesn't support expect-continue and will not send it on subsequent requests. Thus the error will only occur once per session.

I haven't used Opera 6 for quite a while, but I just checked the source and can confirm that it handles http-continue exactly like Opera 7. Thus, it should also exhibit the problem.

23146[/snapback]

I'll check with Ethereal on the next large spam I get and report.

...Stu

Link to comment
Share on other sites

Ok, that I haven't seen.

I'll check with Ethereal on the next large spam I get and report.

23193[/snapback]

Ok, on a spam Outlook claims is 22 Kb I see Opera 6.06 send the POST, but it does not contain the Expect: 100-continue header. Probably why I don't see this problem.

...Stu

Link to comment
Share on other sites

Just an oh-by-the-way ... I had sent a good-sizd e-mail upstream, referencing a number of Topics here, a response from an Akamai support guy, etc ... unfortuntely, I was composing that e-mail when this Forum thing "went dark" <g> ... anyway, yes, data is headed in Julian's direction <g>

Link to comment
Share on other sites

  • 1 month later...
  • 2 months later...

No idea who that person is at this point. A bit of a side note, the IPB forum just went to an alpha version of the next version of this application, and they are running into all kinds of issues trying to support Opera ... and again, can't help but notice that there aren't a lot of other folks expressing complaints with this same problem ..???

However, how about taking a look at another connection problem work through and try something similar ... in theory jumping around whatever Akamai server you're now using and see if that makes any difference ... jump to my specific post in that discussion http://forum.spamcop.net/forums/index.php?...indpost&p=26799

Link to comment
Share on other sites

jumping around whatever Akamai server you're now using and see if that makes any difference

Sadly, it doesn't. I tried an US server by entering

66.77.165.146 www.spamcop.net

66.77.165.137 mailsc.spamcop.net

in my hosts file, but it exhibits the same symptoms.

and again, can't help but notice that there aren't a lot of other folks expressing complaints with this same problem

Which probably only means that there are very few people manually submitting large spams using Opera. And of those few, probably no-one else bothers to report such a problem.

I tested the above US servers with Opera 6.06, 7.54 and 8.01, and in all cases, reporting a spam >10kB shows the problem, viz. a page full of "HTTP/1.1 100 Continue".

Link to comment
Share on other sites

The following sent upstream;

http://forum.spamcop.net/forums/index.php?showtopic=3435

Bit of an ancient Topic, but apparently still an issue for

this user. Various versions of Opera, packet sniffer in

use, submitting 'large' spams via the web-form ... though

kicked up once before, I can't recall a specific answer

on this one. Short of recommending use of other tools,

any clues?

The developer of the web-forum app rolled out an

alpha of the new version last week, and Opera support

has been a major issue due to things that Opera

doesn't support. Whether there's a connection or

not, I have no idea

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...