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Re: cURL crashes with HTTPS proxies

From: Daniel Stenberg <daniel_at_haxx.se>
Date: Sat, 2 Dec 2006 22:32:22 +0100 (CET)

On Sat, 2 Dec 2006, Andreas Rieke wrote:

> From a linux machine (redhat enterprise 3), I do HTTPS requests to a host
> where only the name is known. I use cURL 7.16.0 and c-ares 1.3.2 and even
> tried the daily snapshots (c-ares-1.3.3-20061129 and curl-7.16.1-20061129)
> with the same results. The proxies used are Aladdin, Bluecoat and squid
> (yes, the connection is going via 3 proxies), and each of these in fact only
> works as a proxy and does NOT open the SSL tunnel.

How do you tell libcurl to go through 3 proxies?

> My client tries to connect to the server periodically every 5 seconds, and
> to make things even more complex, the first connections work fine. However,
> after about 50 seconds, cURL crashes within curl_multi_perform (and I even
> do not know if it crashes within c-ares or within cURL).

You don't know? How about building with debug and check with a debugger?

> I was able to find a workaround using the old version cURL 7.15.3 and c-ares
> 1.3.0 where I did not find a single crash within 2 days. I also tried the
> current version with a single squid proxy, also without any crashes or
> problems.

Now that's interestng. In libcurl's view, what really differs between using
one or more proxies? I can't see how it makes any difference...

> However, I would rather use the current versions of both c-ares and cURL
> instead of running old ones.

And we rather fix the bugs!

> Does anybody have an idea about changes from the old to the new versions
> mentionend which could cause the problem?

7.16.0 introduced a lot of internal changes due to the added pipelining
support, but since you compared with 7.15.3 we can also add the whole
curl_multi_socket() API internal remake.

To put it short: I don't think it helps trying to track source code changes
from the working version to the crashing one, I think we need to figure out
why the existing code crashes and fix it!

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Received on 2006-12-02