The Right Hump

Probably the only thing about the N900 that I have found really annoying is the lack of support for the 'Standard' IMAP Sent Items feature. You know the one, where your sent mail goes after you send it.

On the N900 the email application (modest), has a local sent items folder, and it is possible to manually move the items (in bulk) to the IMAP sent items folder, but what a pain.

Anyway, since I have now got fully working server-side filtering (Sieve) I decided it should be possible to solve this problem, server-side.

Since all my outgoing mail goes via Exim, on my own server, I can work out that its being sent from the N900 (I have a different 'from' address). So I can get exim to deliver a copy of the mail to myself. Then I can get Sieve to deliver the mail to my Sent Items.

First I need to add a system filter to exim:

I add the following line to /etc/exim4/conf.d/main/02_exim4-config_options

system_filter=/etc/exim4/system.filter

Exim will now evaluate the rules in /etc/exim4/system.filter before routing the mail.

Create a rule:

if $sender_address is "n900_from_address@wherever.com" then unseen deliver some_local_user@here.com endif

Then add a Sieve rule:

if envelope :is "from" "n900_from_address@wherever.com" { fileinto :flags ["\\Seen"] "INBOX.Sent"; stop; }

Categories: Debian, Linux

One of the problems (and best things) with using IMAP is that you really need to have you email rules and filters server side if you intend to use more than one client.

Sieve Avelsieve , and a Thunderbird plugin .

Since the LinkStation is already short of memory and CPU I've been thinking of re-vamping the e-mail handling for quite a while.

The current configuration uses exim & courier (IMAP and POP3). I have wanted to get rid of POP3 entirely, but the lack of server-side rules made that undesirable (I don't like the idea of client-side rules, very inefficient with large messages).

Exim and Courier are currently tied together, since SMTP user authentication is currently done through the courier-authdaemon (yet another unnecessary process).

The plan is as follows:

1. Remove the tie between Exim and Courier, this will involve making Exim authenticate using PAM.
2. Convert users mailboxes from Courier format to Dovecot (this is only required for users with mail in their Maildir.
3. Install and Configure Dovecot IMAP, POP3 IMAPS, and POP3S
4. Have exim perform its local delivery using the Dovecot Local Delivery Agent (LDA)
5. Configure Sieve
6. Install & Configure Avelsieve

Step 1.

PAM authentication for Exim.

It turns out that the exim-heavy Debian package is already built with PAM support, so we dont have too much to do.

Create a file /etc/pam.d/exim

#%PAM-1.0 @include common-auth @include common-account @include common-session

Add Debian-exim to the shadow group

adduser Debian-exim shadow

Create the auth configuration for Exim. I am using Exim split configuration, so the configuration should go in /etc/exim4/conf.d/auth . I removed the previous auth files leaving only 00_exim4-config_header . Create a file 30_exim4-config_pam_auth .

# /etc/exim4/conf.d/auth/30_exim4-config_pam_auth login: driver = plaintext public_name = LOGIN server_prompts = "Username:: : Password::" server_condition = "${if pam{$1:$2}{1}{0}}" server_set_id = $1 .ifndef AUTH_SERVER_ALLOW_NOTLS_PASSWORDS server_advertise_condition = ${if eq{$tls_cipher}{}{}{*}} .endif

The server is configured only to offer LOGIN authentication when the connection is encrypted, otherwise we'll have cleartext passwords flying all over the 'net.

Step 2.

Although Maildir is some kind of standard, it seems the IMAP and POP servers keep control files with the directory. If the Maildir contains mails (read or unread), it needs to be converted to work with Dovecot, otherwise the mail client will download all the mail again, and wont have a record of which mail is read and unread etc.

This process did not seem to work 100%, Thunderbird still insisted on downloading a bunch of mails, however for the most part everything was fine, and no mail was lost.

Other ideas for converting the Maildir are to copy all mails locally (to local folders in Thunderbird), recreate the Maildir, and then copy them back from Thunderbird, after Dovecot has been upgraded. The Dovecot Wiki has a number of pages on migration.

I used this script , following the instructions from here .

Step 3.

Dovecot configuration is pretty easy. The Debian packages come pre-configured with pretty much everything ready to go.

The basic Dovecot config (all comments removed) looks like this:

protocols = imap imaps pop3 pop3s


listen = * disable_plaintext_auth = no shutdown_clients = yes log_timestamp = "%Y-%m-%d %H:%M:%S "


ssl = yes ssl_cert_file = /etc/ssl/certs/CERT.crt ssl_key_file = /etc/ssl/private/PRIVATE.key


mail_location = maildir:~/Maildir


namespace private { prefix = INBOX. separator = . inbox = yes }


mail_privileged_group = mail


protocol imap { } protocol pop3 { pop3_uidl_format = %08Xu%08Xv }


protocol lda { postmaster_address = postmaster }


auth default { mechanisms = plain passdb pam { args = dovecot } userdb passwd { } user = root


}

NOTE:

It looks like we are allowing plaintext authentication....we are, however our firewall blocks the non-TLS ports from the outside world, so a plain-text password should only ever be passed on the LAN.

Step 4.

As it happens, everything should be up-and-running just fine now. Mail can be delivered, and collected, however the main thrust of this exercise is to get us into a state where we can run have Sieve rules running against received mails. The Dovecot Sieve implementation is a plugin to deliver , the Dovecot Local Delivery Agent. This means that we need to tell exim to use this program to perform local delivery.

Once again Debian make this particularly easy for us:

First create the config for exim:

#/etc/exim4/conf.d/transport/30_exim4-config_dovecot_delivery


dovecot_delivery: driver = pipe command = /usr/lib/dovecot/deliver message_prefix = message_suffix = log_output delivery_date_add envelope_to_add return_path_add #group = mail #mode = 0660 temp_errors = 64 : 69 : 70: 71 : 72 : 73 : 74 : 75 : 78

This defines the transport for the delivery, now we just tell exim to use this transport, edit /etc/exim4/update-exim4.conf.conf and change the dc_localdelivery setting:

dc_localdelivery='dovecot_delivery'

Be sure to restart exim after making these changes.

At this point end-to-end functionality should be tested. Everything should be working as before.

Step 5.

After completing this step we should have 2 pieces of new functionality.

1. Dovecot deliver should evaluate Sieve scripts during mail delivery
2. The Dovecot daemon should listen on port 4190 for Managesieve requests, which allows us to update Sieve scripts remotely

We need to make a couple of modifications to the Dovecot configuration, dovecot.conf .

Modify the protocols line

protocols = imap imaps pop3 pop3s managesieve

This enables the managesieve protocol in Dovecot, however by default Dovecot seems to listen on port 2000. This will most likely be changed in a future versions, since IANA have assigned the port now according to this .

Add the following section to the Dovecot configuration, the make it listen on 4190:

protocol managesieve { listen = localhost:4190 }

Since I am planning only to allow script editing via Avelsieve, I have chosen to only have this listen on localhost, Change 'localhost' to a '*' for all interfaces, but you may want to confirm that the connection is such that you are not passing passwords in cleartext across the net.

Now we need to configure the Dovecot LDA to run sieve scripts:

protocol lda { postmaster_address = postmaster mail_plugins = sieve }

And configure the delivery plugin itself:

plugin { sieve=~/.dovecot.sieve sieve_dir=~/sieve }

See the Dovecot Sieve page for all of the options.

You should be able to check its working using the sieve-connect util, but thats far too much like hard work, we'll use Avelsieve.

Step 6.

Avelsieve is a plugin for SquirrelMail. The last release was over a year ago now, so I dont know how active the development is, but it looks promising enough. There is a Debian package in unstable, which seems to have everything configured.

I had to make one other modification to my system, but that may just be because of the way I am configured...

The Avelsieve client makes use of the Scriptaculous JS library, which although was installed by the Debian package, I needed to make a symlink at the root of my web server to ensure these files were loadable via HTTP.

# cd <WEBROOT>


# ln -s /usr/share/javascript/

Job Done!

Categories: Debian, Linux

After updating debian sid, the propriatary NVIDIA driver no longer loads. Its because the kernel is now built with 'nouveau' support.

nouveau is an open source kernel driver for the nVidia cards. Its not quite as fully featured as the propriatary one, and since I want the 3d support, I'm stuck.

Just

echo 'blacklist nouveau' >> /etc/modprobe.d/blacklist.conf

To prevent the nouveax module being loaded at boot

Categories: Debian

 

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