I'm trying to block hotlinking of images from just some particular
domains.
I've created a .htaccess file as shown below. Some times this
seems to work, and sometimes it doesn't. I'm baffled by
the inconsistent results.
Here are two successive lines from the log file (wrapped for clarity).
In the first case the image is blocked, but in the second it's not.
I've also had the condition where the image is blocked for one
request, but not for a subsequent one from the same site.
Any ideas what's going on?

log file:
------- first request
66.XXXX - - [19/May/2005:10:28:49 -0400]
"GET /panoramic_horizontal/hawaii/maui/images/maui_sunset_hpan.jpg
HTTP/1.1"
304 - "http://www.xanga.com/home.aspx?user=lisalyn"
"Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.8)
Gecko/20050511 Firefox/1.0.4"
-------second request
66.XXXX - - [19/May/2005:10:29:16 -0400]
"GET /panoramic_horizontal/scenic/images/sunset_over_water2.jpg
HTTP/1.1"
200 36747 "http://www.xanga.com/home.aspx?user=MILESmayLIEbetweenUS"
"Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.8)
Gecko/20050511 Firefox/1.0.4"

---- .htaccess file:

RewriteEngine On
RewriteCond %{HTTP_REFERER} ^http://(www\.)?xanga\.com/ [NC,OR]
RewriteCond %{HTTP_REFERER} ^http://(www\.)?myspace\.com/ [NC]
RewriteRule \.(jpe?g|gif|bmp|png)$ - [F,L]
---------
Thanks in advance for any suggestions.

--
Robert D Feinman
Landscapes, Cityscapes and Panoramic Photographs
http://robertdfeinman.com
mail: robertdfeinman@netscape.net

Robert Feinman <robertdfeinman@netscape.net> wrote:
> I've created a .htaccess file as shown below. Some times this
> seems to work, and sometimes it doesn't. I'm baffled by
> the inconsistent results.

> Any ideas what's going on?

> RewriteCond %{HTTP_REFERER} ^http://(www\.)?xanga\.com/ [NC,OR]
> RewriteCond %{HTTP_REFERER} ^http://(www\.)?myspace\.com/ [NC]

There's no requirement for a browser to tell you the referrer, and even
if it does it might be spoofed. Basically, you shouldn't rely on it.

Chris

In article <6ah0m2-cu5.ln1@news.roaima.co.uk>, chris-usenet@roaima.co.uk
says...
> Robert Feinman <robertdfeinman@netscape.net> wrote:
> > I've created a .htaccess file as shown below. Some times this
> > seems to work, and sometimes it doesn't. I'm baffled by
> > the inconsistent results.
>
> > Any ideas what's going on?
>
> > RewriteCond %{HTTP_REFERER} ^http://(www\.)?xanga\.com/ [NC,OR]
> > RewriteCond %{HTTP_REFERER} ^http://(www\.)?myspace\.com/ [NC]
>
> There's no requirement for a browser to tell you the referrer, and even
> if it does it might be spoofed. Basically, you shouldn't rely on it.
>
> Chris
>
That's not the problem. The problem is that for requests where the
referrer matches the conditions above the rewrite is not taking place.
I'm not trying to block everything, just the ones I listed.

--
Robert D Feinman
Landscapes, Cityscapes and Panoramic Photographs
http://robertdfeinman.com
mail: robertdfeinman@netscape.net

Robert Feinman <robertdfeinman@netscape.net> writes:
> That's not the problem. The problem is that for requests where the
> referrer matches the conditions above the rewrite is not taking place.
> I'm not trying to block everything, just the ones I listed.

Setting the rewrite log level to 9 and examining the log output is
often useful in debugging this type of problem.