squid proxy - howto allow tcp connect - getting TCP_DENIAL/400 with ERR_INVALID_DOMAIN
I'm having a device which needs to connect to an internet service on tcp:80 but the network has no direct internet access. So I'm using a squid proxy to solve this.
The device allows me to enter proxyserver, port, username and password.
I figured out, that the device uses http CONNECT instead of http GET (which is working fine with my browser).
When the device tries to connect, it gets an http error 400. The squid access.log gives me only this:
1338885433.033 0 172.22.140.129 TCP_DENIED/400 1728 CONNECT :0 - NONE/- text/html
So I captured the packets to really see whats going on:
Request from device:
CONNECT mydomain.com:0 HTTP/1.0 User-agent: Sequencer/5.5.0.5539
Answer from squid:
HTTP/1.0 400 Bad Request squid/2.7.STABLE9 X-Squid-Error: ERR_INVALID_URL 0 close
My squid.conf:
auth_param basic program /usr/lib/squid/pam_auth auth_param basic children 5 auth_param basic realm Squid proxy-caching web server auth_param basic credentialsttl 2 hours auth_param basic casesensitive off acl all src all acl manager proto cache_object acl localhost src 127.0.0.1/32 acl to_localhost dst 127.0.0.0/8 0.0.0.0/32 acl localnet src 10.0.0.0/8 # RFC1918 possible internal network acl localnet src 172.16.0.0/12 # RFC1918 possible internal network acl localnet src 192.168.0.0/16 # RFC1918 possible internal network acl SSL_ports port 443 # https acl SSL_ports port 563 # snews acl SSL_ports port 873 # rsync 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 Safe_ports port 631 # cups acl Safe_ports port 873 # rsync acl Safe_ports port 901 # SWAT acl purge method PURGE acl CONNECT method CONNECT acl checkpw proxy_auth REQUIRED http_access allow manager localhost http_access deny manager http_access allow purge localhost http_access deny purge http_access deny !Safe_ports http_access allow CONNECT http_access allow localnet http_access allow localhost http_access allow checkpw all http_access deny all icp_access allow localnet icp_access deny all http_port 3128 hierarchy_stoplist cgi-bin ? access_log /var/log/squid/access.log squid debug_options ALL,1 33,2 28,9 refresh_pattern ^ftp: 1440 20% 10080 refresh_pattern ^gopher: 1440 0% 1440 refresh_pattern -i (/cgi-bin/|\?) 0 0% 0 refresh_pattern (Release|Packages(.gz)*)$ 0 20% 2880 refresh_pattern . 0 20% 4320 acl shoutcast rep_header X-HTTP09-First-Line ^ICY.[0-9] upgrade_http0.9 deny shoutcast acl apache rep_header Server ^Apache broken_vary_encoding allow apache extension_methods REPORT MERGE MKACTIVITY CHECKOUT hosts_file /etc/hosts forwarded_for off coredump_dir /var/spool/squid
Is there any solution to get rid of the ERR_INVALID_URL? Did I missunderstood the concept of the squid proxy or is the request from the device invalid?
Please let me know if any other information is needed.
Thank you in advance, Christian.
Answer
I resolved the same error by commenting out from the default squid.conf:
# Deny CONNECT to other than secure SSL ports
#http_access deny CONNECT !SSL_ports
By default Squid is set up to not allow CONNECT to non-SSL ports. If you want to test without SSL you can disable this by commenting out the line above.