Daniel Stenberg wrote:

> On Thu, 7 Mar 2002, David Burley wrote:
>
> > I know from looking at what I am posting to them "curl -v" that the post
> > data, the unique values anyways, are unique for each and every instance.
> > The cookie files are also being stored independently of one another and are
> > being deleted after each round of requests.
> >
> > Thus, I come to the conclusion that something must be common between the
> > instances of cURL. Else, I would think that they would detect multiple
> > instances with one copy of cURL and one copy of Internet Explorer open and
> > they do not. Could the commonalities be coming from the SSL implementation
> > (in other words... not cURL or libcURL's problem)?
>
> Actually, I fail to see how this is a problem at all. I think this is just a
> matter of the site having a stupid check that doesn't work for generic
> user-agents.

The check maybe stupider than you think. The site might be allowing one
connection from each of any given user-agent (MSIE, Mozilla, etc) at a
particular originating IP.

If so, curl-from-a-script + MSIE is OK. curl-from-a-script twice would not be
OK on the occasions when the scripts invoke curl simultaneously.

Just for grins, David, try making several copies of your script and add
different "--user-agent" options to the curl invocations - let one copy use the
default, set another to "Mozilla/4.0", another to the id string for MSIE, etc.
Crank them all up at the same time and see what falls out of the woodwork.

If it works, there's your method for defeating the check - just make sure no two
copies of the script fake the same user-agent...

I have absolutely no clue why that would be a useful thing to check... :)

> [...] How do the site detect multiple simultaneous connects anwyay? It would
> probably check for the same remote IP address for more than one TCP connect,
> and then I can't see how curl can circumvent that!

But the site apparently allows IE + curl, but not IE + (2 x curl), so it isn't
just counting connects from the same IP...

Ralph Mitchell
Received on 2002-03-08