The proxy is now running on my local server which sits behind the real gateway. Besides making the device use the server as gateway and enable NAT on the server this single iptables rule is all that is needed:

iptables -t nat -A PREROUTING -s $CLIENT_IP -p tcp --dport 80 -j REDIRECT --to-port 8080

I’m using Ubuntu 11.10 on amd64.

I don’t really know the best way to do this, but I did it by adding the following line to hooks/post-update:

git push --mirror git@gitorious.org:licq/debian.git

This way the mirror will always be updated when I push to the “real” repository.

Get it by running

% gbp-clone --pristine-tar git://gitorious.org/licq/debian.git

or clone it on Gitorious and send me merge requests

For now I’ll settle with the fact that I have at least contributed something to my favorite OS. Even if it took some convincing to get it in. But then again, I’m glad they don’t just accept patches from any random Joe Developer without reviewing it.

alias cless='LESSOPEN="| highlight --ansi --force %s" less -NR'

Tip: If you’d like more colors, replace –ansi with –xterm256.

We’ll start with exim. First of all, we’ll need a router that will pass all incoming email through dspam. Since I use ldap to store all domains and users, it might look a bit intimidating. But, as always, the documentation is your friend. Anyhow, the interesting part is the condition.

dspam_router:
  driver = accept
  no_verify
  domains = +virtual_domains
  hide local_parts = ${lookup ldap {user=LDAP_USER pass=LDAP_PASS \
    ldap:///dc=${quote_ldap_dn:$domain},ou=domains,dc=ejohansson,dc=se?uid?one?\
    (&(objectClass=posixAccount)(uid=${quote_ldap:$local_part}@$domain))}\
    {${extract{1}{@}{$value}}} fail}
  local_part_suffix = +*
  local_part_suffix_optional

  # When to scan a message :
  # - it isn't already scanned
  # - it isn't local
  # - it is less than 512k in size
  condition = "${if and {\
    {!eq {$received_protocol}{spam-scanned}}\
    {!eq {$received_protocol}{local}}\
    { <= {$message_size}{512k}}\
    } {1}{0}}"
  headers_add = "X-FILTER-DSPAM: by $primary_hostname on $tod_full"
  transport = dspam_spamcheck

If the message matched the condition, it will be sent to the dspam_spamcheck transport. Which looks like follows.

dspam_spamcheck:
  driver = pipe
  command = "/usr/bin/dspam --deliver=innocent,spam \
    --user '${lc:$local_part}@${lc:$domain}' -- \
    -f '$sender_address' %u"
  home_directory = "/var/spool/dspam"
  current_directory = "/var/spool/dspam"
  user = dspam
  group = dspam
  log_output = true

  return_fail_output = true
  return_path_add = false
  message_prefix =
  message_suffix =

This will check the message and then send it to exim, to have it pass through the exim router chain once more. But this time, since we'll be using the spam-scanned protocol, it wont match the condition in dspam_router. But for this to work, we need to set the delivery agent in dspam.conf.

TrustedDeliveryAgent "/usr/sbin/exim4 -oMr spam-scanned"

Then we need to give the dspam user right to set the received protocol. We do this by adding dspam to the list of trusted_users in our exim conf.

See the configuration files for more details and the DSPAM wiki for even some more.

If you have comments or would like me too explain something a bit more, please don't hesitate to leave a comment or drop me a mail.

/me like! (more)

receive_packet failed on eth1: Network is down

The only thing I noticed was that even though I explicitly set the rate to 11M, it was set to 54M after running dhclient. So it seemed like dhclient was doing something funny. But I was unable to pinpoint the exact problem and left it be for the time.

Today I found a solution in this thread. It’s not a permanent solution, rather some kind of a hack, but it works.

First bring up the interface.

# ifconfig eth1 up

Next, and this is the key, associate the interface at the same time as dhclient is DHCPDISCOVERing. Run this command in one terminal.

# dhclient eth1

When you get output similar to this

DHCPDISCOVER on eth1 to 255.255.255.255 port 67 interval 7

you run this command in another terminal.

# iwconfig eth1 channel 11 rate 11M essid "Erik" enc <secret password>

Of course you’ll have to replace “Erik” etc with your settings.

And, once again, I’m able to say: the wireless network card (AirPort Extreme) is now working.