I have beening running webserver at my home linux computer for two years http://pingpongit.homelinux.com . I am using DynDNS http://www/dyndns.com free dynamic dns services to resolve my home dynamic IP.

I need to run a dynmaic dns update client to update the record once my IP changed. I am having problem using the popular ddclient, it just won't update for some reason. It is written in Perl, I am comfortable with Perl, but just could not figure out why. I ended up with another update client called addns.pl http://www.funtaff.com/software/addns.pl/ which works for me. but one side effect is that addns.pl does not have http ssl support which is recommended to encrypt the communication. so I modified the addns.pl to support http ssl, here is the patch I added:

--- addns.orig 2006-09-24 13:52:08.699253528 -0700
+++ addns 2006-09-24 13:54:22.933846768 -0700
@@ -7,7 +7,7 @@
# Version 1.2
# www.funtaff.com

-use IO::Socket;
+use IO::Socket::SSL;
use Sys::Hostname;
use integer;
use English;
@@ -288,7 +288,7 @@

chomp( $coded = encode_base64("$uname:$passwd") );

- $msg = "GET http://$server_host/nic/update?";
+ $msg = "GET https://$server_host/nic/update?";
$msg .= "system=$system_type";
$msg .= "&hostname=$updt_host";

@@ -311,25 +311,18 @@
$msg .= "\r\n";

#tcp code
- my ( $proto, $iaddr, $sin, @return );
- my $socket_type = 'tcp';
-
- $proto = getprotobyname($socket_type);
- socket( UpdaTe, PF_INET, SOCK_STREAM, $proto ) || die "socket: $!";
- $iaddr = gethostbyname($connect_host);
- $sin = sockaddr_in( $port, $iaddr );
-
- connect( UpdaTe, $sin ) || die "connect: $!";
- output( "$curr_host: performing update, ip=$ip", 1, 1 );
-
- if ( $debug > 1 ) {
- print "\n--Client Request--\n";
- print "$msg\n";
+ my $sock = IO::Socket::SSL->new(
+ PeerAddr => $connect_host,
+ PeerPort => $port,
+ Proto => 'tcp',
+ );
+ defined $sock or output("cannot connect to $connect_host:$port socket: $@");
+ my @return;
+ if ( defined $sock ) {
+ syswrite $sock, $msg;
}
-
- send( UpdaTe, $msg, 0 );
- @return = <UpdaTe>;
- close(UpdaTe);
+ @return = <$sock>;
+ $sock->close;

if ( $debug > 1 ) {
print "--Server Response--\n";


--- addns.conf.orig 2006-09-24 14:24:18.617861304 -0700
+++ addns.conf 2006-09-24 13:48:46.059059520 -0700
@@ -13,8 +13,9 @@
iface = "eth0"
username = "user"
password = "password"
- server_port = 80
+ server_port = 443
server_host = members.dyndns.org
+ mx_host = my mx host
}

I also added my mx host so that I could relay my registed dyndns subdomain and have my email address as vincent at pingpongit.homelinux.com.

I spent a little time to read the Amavis and Amavis::AV package section of Amavisd-new-2.3.3. It has two ways to call clamav which is configured in /etc/amavisd.conf, calling Mail::CLamAV is memory hungry, talking to clamav unix socket is much more efficient :

!!!Note: the Line number which has '!!!' in front is the trace that subroutine are calling each other.



----------
@av_scanners = (
# ### http://www.clamav.net/
['ClamAV-clamd',
\&ask_daemon, ["CONTSCAN {}\n", "/var/run/clamav/clamd.sock"],
qr/\bOK$/, qr/\bFOUND$/,
qr/^.*?: (?!Infected Archive)(.*) FOUND$/ ],
# # NOTE: the easiest is to run clamd under the same user as amavisd; match the
# # socket name (LocalSocket) in clamav.conf to the socket name in this entry
# # When running chrooted one may prefer: ["CONTSCAN {}\n","$MYHOME/clamd"],

# ### http://www.clamav.net/ and CPAN (memory-hungry! clamd is preferred)
# ['Mail::ClamAV', \&ask_clamav, "*", [0], [1], qr/^INFECTED: (.+)/],
.....snip...
.....snip....
);

#@av_scanners is a list of n-tuples, where fields semantics is:
# @av_scanners is a list of n-tuples, where fields semantics is:
# 1. av scanner plain name, to be used in log and reports;
# 2. scanner program name; this string will be submitted to subroutine
# find_external_programs(), which will try to find the full program path
# name during startup; if program is not found, this scanner is disabled.
# Besides a simple string (full program path name or just the basename
# to be looked for in PATH), this may be an array ref of alternative
# program names or full paths - the first match in the list will be used;
# As a special case for more complex scanners, this field may be
# a subroutine reference, and the whole n-tuple is passed to it as args.
# 3. command arguments to be given to the scanner program;
# a substring {} will be replaced by the directory name to be scanned, i.e.
# "$tempdir/parts", a "*" will be replaced by base file names of parts;
# 4. an array ref of av scanner exit status values, or a regexp (to be
# matched against scanner output), indicating NO VIRUSES found;
# a special case is a value undef, which does not claim file to be clean
# (i.e. it never matches, similar to []), but suppresses a failure warning;
# to be used when the result is inconclusive (useful for specialized and
# quick partial scanners such as jpeg checker);
# 5. an array ref of av scanner exit status values, or a regexp (to be
# matched against scanner output), indicating VIRUSES WERE FOUND;
# Note: the virus match prevails over a 'not found' match, so it is safe
# even if the no. 4. matches for viruses too;
# 6. a regexp (to be matched against scanner output), returning a list
# of virus names found, or a sub ref, returning such a list when given
# scanner output as argument;
# 7. and 8.: (optional) subroutines to be executed before and after scanner
# (e.g. to set environment or current directory);
# see examples for these at KasperskyLab AVP and NAI uvscan.

-------------------------


The package Amavis is doing the main work of amavisd including if doing virus scan, spam scan...

7627 package Amavis;
7628 require 5.005; # need qr operator and \z in regexps
7629 use strict;
7630 use re 'taint';
......snip.........
8407 ### The heart of the program
8408 ### user customizable Net::Server hook
8409 sub process_request {
.....snip....

8834 # Checks the message stored on a file. File must already
8835 # be open on file handle $msginfo->mail_text; it need not be positioned
8836 # properly, check_mail must not close the file handle.
8837 #
8838 sub check_mail($$$) {
.........snip.......


9187 my ($av_ret);
9188 eval {
9189 my ( $vn, $ds );
9190 ( $av_ret, $av_output, $vn, $ds ) =
!!!9191 Amavis::AV::virus_scan( $tempdir, $child_task_count == 1,
!!!9192 $parts_root );
9193 @virusname = @$vn;
9194 @detecting_scanners = @$ds; # copy
9195 };
......snip........
9254 # consider doing spam scanning
9255 if ( !$extra_code_antispam ) {
9256 do_log( 5, "no anti-spam code loaded, skipping spam_scan" );
9257 }
9258 elsif (@virusname) {
9259 do_log( 5, "infected contents, skipping spam_scan" );
9260 }
9261 elsif ($banned_filename_all) {
9262 do_log( 5, "banned contents, skipping spam_scan" );
9263 }

...........snip.........
9281 else {
9282 $which_section = "spam_scan";
9283 ( $spam_level, $spam_status, $spam_report, $autolearn_status ) =
9284 Amavis::SpamControl::spam_scan( $conn, $msginfo );


........snip........


11424 #
11425 # Main program starts here
11426 #
11427
11428 # Read dynamic source code, and logging and notification message templates
11429 # from the end of this file (pseudo file handle DATA)
11430 #
11431 $Amavis::Conf::notify_spam_admin_templ = ''; # not used
11432 $Amavis::Conf::notify_spam_recips_templ = ''; # not used
11433 do {
11434 local ($/) = "__DATA__\n"; # set line terminator to this string
11435 chomp( $_ = <Amavis::DATA> ) for (
.............snip..........

11798 # set up Net::Server configuration
11799 my $server = bless {
11800 server => {
........snip........
11846
11847 %content% = 'amavisd (master)';
11848 $server->run; # transfer control to Net::Server
11849
11850 # shouldn't get here
11851 exit 1;
11852

End package Amavis

package Amavis::AV;

....
.....

#ask_daemon is a subroutine available for calling from @av_scanners list entries;
#it has the same args and returns as run_av() below

!!!15028 sub ask_daemon { ask_av(\&ask_daemon_internal, @_) }

# ask_av is a common subroutine available to be used by ask_daemon, ask_clamav,
# ask_sophos_savi and similar front-end routines used in @av_scanners entries.
# It traverses supplied files or directory ($bare_fnames) and calls a supplied
# subroutine for each file to be scanned, summarizing the final av scan result.
# It has the same args and returns as run_av() below, prepended by a checking
# subroutine argument.
15291 sub ask_av {
15292 my($code) = shift; # strip away the first argument, a subroutine ref
15293 my($bare_fnames,$names_to_parts,$tempdir, $av_name,$command,$args,
15294 $sts_clean,$sts_infected,$how_to_get_names) = @_;
15295 my($query_template) = ref $args eq 'ARRAY' ? $args->[0] : $args;
.....snip.....
.....
!!!15310 my($t_status,$t_output) = &$code($query, @_);
.....
...
do_log(3,"$av_name result: clean") if defined($scan_status) && !$scan_status;
($scan_status,$output,\@virusname);
}

subroutine ask_daemon_internal is doing the actual virus scanning work

# same args and returns as run_av() below,
# but prepended by a $query, which is the string to be sent to the daemon.
# Handles both UNIX and INET domain sockets.
# More than one socket may be specified for redundancy, they will be tried
# one after the other until one succeeds.
#
15201 sub ask_daemon_internal {
15202 my($query, # expanded query template, often a command and a file or dir name
15203 $bare_fnames,$names_to_parts,$tempdir, $av_name,$command,$args,
15204 $sts_clean,$sts_infected,$how_to_get_names, # regexps
15205 ) = @_;
........snip......
15237 # UGLY: bypass send method in IO::Socket to be able to retrieve
15238 # status/errno directly from 'send', not from 'getpeername':
15239 defined send($st_sock{$socketname}, $query, 0)
15240 or die "Can't send to socket $socketname: $!\n";
15241 my($rv); my($buff) = ''; undef $!;
!!!15242 while (defined($rv = $st_sock{$socketname}->recv($buff,8192,0))) {
*15243 $output .= $buff;
15244 last if $multisession || $buff eq '';
15245 undef $!;
........snip.......
15282 (0,$output); # return synthesised status and result string
15283 }

# Call a virus scanner and parse its output.
# Returns a triplet (or die in case of failure).
# The first element of the triplet is interpreted as follows:
# - true if virus found,
# - 0 if no viruses found,
# - undef if it did not complete its job;
# the second element is a string, the text as provided by the virus scanner;
# the third element is ref to a list of virus names found (if any).
# (it is guaranteed the list will be nonempty if virus was found)
#
15356 sub run_av {
15357 # first three args are prepended, not part of n-tuple
15358 my($bare_fnames, # a ref to a list of filenames to scan (basenames)
15359 $names_to_parts, # ref to a hash that maps base file names to parts object
15360 $tempdir, # temporary directory
15361 $av_name, $command, $args,
15362 $sts_clean, # a ref to a list of status values, or a regexp
15363 $sts_infected, # a ref to a list of status values, or a regexp
15364 $how_to_get_names, # ref to sub, or a regexp to get list of virus names
15365 $pre_code, $post_code, # routines to be invoked before and after av
15366 ) = @_;
15367 my($scan_status,$virusnames,$error_str); my($output) = '';
15368 &$pre_code(@_) if defined $pre_code;
!!!15369 if (ref($command) eq 'CODE') {
!!!15370 do_log(3,"Using $av_name: (built-in interface)");
!!!15371 ($scan_status,$output,$virusnames) = &$command(@_);
15372 } else {
........snip.........
15431 ($scan_status, $output, $virusnames);
15432 }


15434 sub virus_scan($$$) {
15435 my($tempdir,$firsttime,$parts_root) = @_;
15436 my($scan_status,$output,@virusname,@detecting_scanners);
15437 cy($anyone_done); my($anyone_tried);
15438 my($bare_fnames_ref,$names_to_parts);
.............................
15455 if (!@$bare_fnames_ref) { # no files to scan?
15456 ($this_status,$this_output,$this_vn) = (0, '', []); # declare clean
15457 } else { # call virus scanner
15458 eval {
15459 ($this_status,$this_output,$this_vn) =
!!!15460 run_av($bare_fnames_ref,$names_to_parts,$tempdir, @$av);
15461 };
....................

15491 ($scan_status, $output, \@virusname, \@detecting_scanners); # return a quad
15492 }

....
....

1;

#END package Amavis::AV

I am still cutomizing SpamPD and hope to add virus scan engine features...

I have been running Amavisd-new for 2 years which works pretty well. But I have a very inconvienent way to release a false positive email to users. I decided to experiment open source MailZu and let user do their quarantine management. MailZu requires that Amavisd-new log mail information to SQL database like MySQL, PostgreSQL.... see the install details on http://www.mailzu.net/docs/INSTALL

There are couple of things need to be considered:

MailZu needs php compiled with imap and socket because MailZu needs imap to connect to imap server and socket to talk to Amavisd AMP protocol to release quarantined email. So I decided to upgrade my Apache/PHP/OpenSSL installation to the latest package.

Here is my upgraded system info and compile options:

Apache/2.2.3 (Unix) mod_ssl/2.2.3 OpenSSL/0.9.8 DAV/2 PHP/5.1.6

Apache: './configure --enable-so --enable-dav --enable-ssl --with-ssl=/usr/local/ssl

PHP: './configure' '--with-apxs2=/usr/local/apache2/bin/apxs' '--with-mysql' '--with-pgsql=/usr/local/pgsql' '--with-imap=/usr/local/imap-c-client' '--enable-sockets'

Note:
1,The Spam/Virus is quarantined to my new MySQL database (4.1.20), but PHP is compiled with the old mysql client library (3.23.58) because the password format is still in 3.23.58 format
2, To compile php with imap, it needs the imap c client *.h and *.c files see http://ca.php.net/imap for more detailes. I ran into problem with imap c client compiling and installation for some reason. But I found I have a left over imap c client folder which contains all the *.h and *.c files while I compile Pine4.64 sometime ago. so copied *.h, *.c to /usr/local/imap-c-client/include and /usr/local/imap-c-client/lib and copied c-client.a to /usr/local/imap-c-client/lib/libc-client.a. I put the folder tar files on http://mcli.brc.ub.ca/imap-c-client.tar

The relevant Amavisd-new config:

+$inet_socket_port = [10024, 9998]; # accept SMTP on this local TCP port
# (default is undef, i.e. disabled)

+$virus_quarantine_method = $spam_quarantine_method =
+ $banned_files_quarantine_method = $bad_header_quarantine_method = 'sql:';

+$sa_quarantine_cutoff_level = 20; # dflt: undef, which disables this feature

+ @storage_sql_dsn = ( ['DBI:mysql:database=mail;host=127.0.0.1;port=3306', 'user', 'password']); # none, same, or separate database
#

+ $policy_bank{'AM.PDP'} = {
+ log_level => 3,
+ inet_acl => [ qw ( 127.0.0.1 [::1] MailZu-host ) ],
+ protocol=>'AM.PDP', # Amavis policy delegation protocol (new milter helper)
+ };
+

+ $interface_policy{'9998'} = 'AM.PDP';

Today, I finally got the order of SAMSUNG 800MHZ ECC for the odd computer I got from my friend. What I mean odd computer is that the mother board only take pair ECC RAMBUS memory, and each time if I unplugged memory, I have to unplug the video card too, then plug memory card and video card back in order. Now it is upraded from 128MB to 512MB, finally I could got a machine to do spam filtering and custom programing test.