[squid-users] TCP_DENIED/403 errors when ads blocking is activated

[Nicolas]

Hello,

I installed squid on one of my servers, in order to block ads.

When I do not activate ads blocking, it works fine.
However, when I do activate ads blocking, some website are not accessible.
I can browse www.google.com for example, but I can't access www.linuxhint.com and a LOT of other websites.

Here's what appears in access.log :
1670071413.742      0 192.168.228.145 TCP_DENIED/403 3985 CONNECT linuxhint.com:443 - HIER_NONE/- text/html

Here's my squid.conf file :
acl localnet src 0.0.0.1-0.255.255.255  # RFC 1122 "this" network (LAN)
acl localnet src 10.0.0.0/8             # RFC 1918 local private network (LAN)
acl localnet src 100.64.0.0/10          # RFC 6598 shared address space (CGN)
acl localnet src 169.254.0.0/16         # RFC 3927 link-local (directly plugged) machines
acl localnet src 172.16.0.0/12          # RFC 1918 local private network (LAN)
acl localnet src 192.168.0.0/16         # RFC 1918 local private network (LAN)
acl localnet src fc00::/7               # RFC 4193 local private network range
acl localnet src fe80::/10              # RFC 4291 link-local (directly plugged) machines
acl SSL_ports port 443
acl Safe_ports port 80          # http
acl Safe_ports port 21          # ftp
acl Safe_ports port 443         # https
acl Safe_ports port 70          # gopher
acl Safe_ports port 210         # wais
acl Safe_ports port 1025-65535  # unregistered ports
acl Safe_ports port 280         # http-mgmt
acl Safe_ports port 488         # gss-http
acl Safe_ports port 591         # filemaker
acl Safe_ports port 777         # multiling http
acl CONNECT method CONNECT
acl ads dstdom_regex "/etc/squid/ad_block.txt"
http_access deny ads
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
http_access allow localhost manager
http_access deny manager
include /etc/squid/conf.d/*
http_access allow localnet
http_access allow localhost
http_access deny all
http_port 8080
cache_dir ufs /cachesquid 600 16 256
coredump_dir /var/spool/squid
refresh_pattern ^ftp:           1440    20%     10080
refresh_pattern ^gopher:        1440    0%      1440
refresh_pattern -i (/cgi-bin/|\?) 0     0%      0
refresh_pattern .               0       20%     4320

Here's how I got the ad_block.txt file :
curl -sS -L --compressed "http://pgl.yoyo.org/adservers/serverlist.php?hostformat=nohtml&showintro=0&mimetype=plaintext" > /etc/squid/ad_block.txt
which is on my server :
-rw-r--r-- 1 root root 60609  2 déc.  16:40 /etc/squid/ad_block.txt

I don't see anything special in that file, which contains for example :
1-1ads.com
101com.com
101order.com
123freeavatars.com
180hits.de
180searchassistant.com

There's only one occurence of linux in that file :
grep -i "linux" /etc/squid/ad_block.txt
banner.linux.se

Do you know why I got those 403 errors? I gave one example only (www.linuxhint.com) but a LOT of websites are not accessible anymore as soon as I add that line in the squid.conf file :
http_access deny ads

Thank you for your help.

Nicolas.