homepage/legacy/posts/2013-06-27.01/article.html

define(`TITLE', `Children Protection for Postfix-based EMail-Server')
define(`DATE', `2013-06-27')
define(`CONTENT', `
This small tool implements a whitelist on a Postfix mail-server. It prevents certain recipient addresses (your kids ones) from receiving mail from any not whitelisted address. Any mail from not whitelisted senders is redirected to a delegate (a parent).

Code is here <a href="http://files.a385e-5.de/files/ChildProt-0.9.tar.gz">http://files.a385e-5.de/files/ChildProt-0.9.tar.gz</a>

Configure it by adding this line into the <em>master.cf</em> of the Postfix installation:
<pre>childprot unix  -       n       n       -       25      spawn user=mail argv=/opt/sbin/ChildProt</pre>
and this to the <em>main.cf</em>:
<pre class="brush: text; gutter: false">smtpd_recipient_restrictions =
  [...]
  check_policy_service unix:private/childprot
  [...]</pre>
The restricted recipients and the whitelists are stored in an SQLite3 database:
<pre class="brush: sql; gutter: false">CREATE TABLE child_address_t (
  child INTEGER REFERENCES child_t(id),
  address TEXT
);

CREATE TABLE child_t (
  id INTEGER PRIMARY KEY,
  name TEXT,
  delegate TEXT
);

CREATE TABLE whitelist_t (
  child INTEGER REFERENCES child_t(id),
  address TEXT
);

CREATE VIEW child_v AS
  SELECT c.id as id,
         c.delegate as delegate,
         ca.address as address
  FROM child_t c,
       child_address_t ca
  WHERE c.id = ca.child;</pre>
Restricted persons together with their delegates are added to the table <em>child_t</em>, multiple addresses can be assigned to those persons in <em>child_address_t</em>. Whitelists per person are maintained in <em>whitelist_t</em>.

The tool is querying the view <em>child_v</em>.

&nbsp;

&nbsp;
')