[squid-users] Squid Redirection Scripting

[Willsz.net]

On 11/04/2017 8:48, Amos Jeffries wrote:
> On 10/04/2017 8:26 p.m., Willsz.net wrote:
>>
>> Hi, folks
>>
>> Hi, I used Perl Scripting for 1 year couple ago. But this script doesn't
>> work with new version Squid.
>
> Please explain "doesn't work".
> Does it make all your traffic divert to cat pictures now?
>   something else?

Thank Amos,

Let me explain more detail, something like this:

root:~# cat /usr/local/bin/squid-rdr
#!/usr/local/bin/perl

$|=1;

while (<>) {
chomp;
@X = split;
$url = $X[0];

     if ( $url =~ m{ ^https?://(?:
         ad[0-9]?        |
         ad[szvx]?[0-9]? |
         ads[0-9]?       |
         adsbox          |
         adserver        |
         adservices?     |
         adserving       |
         adv             |
         advertising     |
         banners?        |
         adserver)\.(.*) }x ) {
             print "http://somedomain.com/null.png\n";
     }

     else {
         print "$url\n";
     }
}

root:~# chown squid:squid /usr/local/bin/squid-rdr
root:~# chmod 755 /usr/local/bin/squid-rdr

Afterward, I add in /usr/local/etc/squid/squid.conf:

url_rewrite_program /usr/local/bin/squid-rdr
url_rewrite_children 32 startup=0 idle=1 concurrency=0
url_rewrite_bypass on

root:~# /usr/local/etc/rc.d/squid.sh reload
Reload proxy system...

Trying to browse some URL, so I get this error message and I failed to 
retrieve web-page.

root:~# tail /var/log/squid/cache.log
2017/04/11 12:24:38 kid1| helperOpenServers: Starting 1/32 'squid-rdr' 
processes
2017/04/11 12:24:38 kid1| assertion failed: ../src/base/Lock.h:30: 
"count_ == 0"


> What was your previous version of Squid.
>  2.7?  3.5.23?  something else?

Sorry, I forgot exactly version, maybe squid-3.5.13/squid-3.5.14. Which 
I remember at that time, I was hit by DDoS. So I change to latest version.

>> Here's my script:
>>
>> #!/usr/local/bin/perl
>>
>> $|=1;
>>
>> while (<>) {
>> chomp;
>> @X = split;
>> $url = $X[0];
>>
>>     if ( $url =~ m{ ^https?://(?:
>>         ad[0-9]?        |
>>         ad[szvx]?[0-9]? |
>>         ads[0-9]?       |
>>         adsbox          |
>>         adserver        |
>>         adservices?     |
>>         adserving       |
>>         adv             |
>>         advertising     |
>>         banners?        |
>>         adserver)\.(.*) }x ) {
>
> Does that regex actually work?
>
> 1) I've never known URLs to contain long series of whitespaces like that.
>
> 2) ad[szvx]?[0-9]? matches the same things as ad[0-9]? and ads[0-9]? and
> adv.

Yes, that script work in previous version of Squid.

>
>>             print "http://somedomain.com/null.png\n";
>>     }
>>
>>     else {
>>         print "$url\n";
>>     }
>> }
>>
>> Anyone guide me to make it work?
>>
>
> From the overall structure and output I am guessing that this is a Squid
> URL re-writer or Store-ID helper.
>
>
> IMO you should replace this simple helper with ACLs. Like so:
>
> squid.conf:
>  acl adverts_domain dtsdom_regex "/etc/squid/adverts_domain.regex"
>  deny_info 302:http://somedomain.com/null.png adverts_domain
>  http_access deny adverts_domain
>
> /etc/squid/adverts_domain.regex:
>    ad[szvx]?[0-9]?\.
>    adsbox\.
>    adserv(er|ing|ices?)\.
>    adv(ertising)?\.
>    banners?\.

OK, let me try first. Thank you Amos.