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PDT module

This module translates a numerical prefix into a domain and updates accordingly the request URI.

The module looks up at the R-URI part of a message and if the user part begins with an established prefix it will update the URI. Updating the uri consists of: remove the prefix from the user part of the uri and keep the rest as the user part of the new uri. The host and port are changed with the domain matched for the leading prefix and the domain in From URI.

<:password>@<mydomain.com> …

and the result will be:

<:password>@<domain[:port]>…

prefix-domain translation
prefix=123, domain(FROM)=siphub.org
entry in database:
sdomain=siphub.org
domain[123]=alpha.org
domain[124]=beta.org
domain[125]=gamma.org
The RURI will be updated in the following way"
sip:12391001@mydomain.com => sip:91001@alpha.org

The prefix could be prefixed by other digits. These digits will not be used to look up the domain (the classic example, 00 used for international calls, then follows the country prefix). For more information on this, see ‘prefix’ parameter.

  • A sample config file is located in ’./doc/’.
  • MySQL script to create the database needed by PDT is located in ’../../scripts/mysql/pdt-create.sql’ The database is loaded by OpenSIPS only at start up time and only cache is used to lookup domains. Check the MI Functions for adding/deleting prefix-domain pairs or reloading from database at runtime.
  • Sample shell scripts to manage prefix-domain pairs are also located in ’./doc/’ (pdt_fifo_add.sh, pdt_fifo_delete.sh, pdt_fifo_list.sh).

The following modules must be loaded before this module:

  • A OpenSIPS database module (e.g., mysql, dbtext).

The following libraries or applications must be installed before running OpenSIPS with this module loaded:

  • None.

URL of the database table to be used.

Default value is “mysql://opensips:opensipsrw@localhost/opensips”.

Set db_url parameter
...
modparam("pdt", "db_url", "dbdriver://username:password@dbhost/dbname")
...

Table name.

Default value is “pdt”.

Set db_table parameter
...
modparam("pdt", "db_table", "pdt")
...

Name of ‘sdomain’ column.

Default value is “sdomain”.

Set sdomain_column parameter
...
modparam("pdt", "domain_column", "source_domain")
...

Name of ‘prefix’ column.

Default value is “prefix”.

Set prefix_column parameter
...
modparam("pdt", "prefix_column", "prefix")
...

Name of ‘domain’ column.

Default value is “domain”.

Set domain_column parameter
...
modparam("pdt", "domain_column", "hostname")
...

Default leading prefix who denotes what URI needs to be translated - if it is NULL the module will not check the R-URI against it and the PDT prefix is considered starting from the first digit. Otherwise, the module will check first if the R-URI starts with it and will skip it to look up the domain.

Default value is NULL.

Set prefix parameter
...
modparam("pdt", "prefix", "00")
...

The list with characters allowed in prefix.

Default value is “0123456789”.

Set char_list parameter
...
modparam("pdt", "char_list", "0123456789*+")
...

Module will check if destination domain is duplicated for same source domain (1 - check; 0 - don’t check).

Default value is 1.

Set check_domain parameter
...
modparam("pdt", "check_domain", 0)
...

prefix2domain(rewrite_mode, multidomain_mode)

Section titled “prefix2domain(rewrite_mode, multidomain_mode)”

Build a new URI if it is necessary. Returns 1 when the translation was made or there was nothing to translate (user part of the URI is empty, it does not match the prefix parameter or there is no domain associated with a possible prefix from user part). Returns -1 in error cases.

The translation is done based on lookup up for a entry in the database where the sdomain equals the domain in FROM uri, and the prefix matches the beginning of the user part of the RURI. If such an entry is found, then the domain in RURI is updated with the domain of this entry (sdomain, prefix, domain).

There is also the possibility to have the translation of URI regardless of source domain. This can be achieved inserting in the database entries where sdomain has the value ”*”.

The “rewrite_mode” parameter specifies whether to strip or not the prefix from user part. The possible values are:

  • 0: the prefix is removed along with the leading prefix.
  • 1: only the leading prefix is removed.
  • 2: the user part of the URI is not changed.
  • $PV : any PV holding one of the above values.

The “multidomain_mode” parameter specifies the kind of multidomain support to use. The possible values are:

  • 0 : Translation of URI regardless of source domain.
  • 1 : Translation of URI using as source domain the domain in From-URI.
  • 2 : Translation of URI using as source domain the domain in From-URI. In case there is no entry for the required sdomain, it tries the translation using ”*” as sdomain.
  • $PV : any PV holding one of the above values.

This function can be used from REQUEST_ROUTE, FAILURE_ROUTE.

prefix2domain usage
...
prefix2domain("2", "2");
...
$var(a) = 1;
prefix2domain("$var(a)", "2");
...

The same as prefix2domain(rewrite_mode, “0”), that is without multidomain support, translation of URI being done regardless of the source domain.

...
prefix2domain("2");
...

The same as prefix2domain(“0”, “0”).

...
prefix2domain();
...

The database is loaded by OpenSIPS at start up time. The module uses only the cache to look up domains. If you want to add or delete a new prefix-domain pair at runtime you have to use MI FIFO commands. All changes made via these commands are applied to database and the cache is updated correspondingly.

Adds a new sdomain-prefix-domain entry.

Name: pdt_add

Parameters:

  • sdomain : source domain
  • prefix: prefix
  • domain: domain corresponding to a pair of source domain and prefix

MI FIFO Command Format:

Terminal window
:pdt_add:_reply_fifo_file_
_sdomain_
_prefix_
_domain_
_empty_line_

Removes a sdomain-prefix-domain entry.

Name: pdt_delete

Parameters:

  • sdomain : a source domain
  • domain: a domain associated via a prefix with the source domain

MI FIFO Command Format:

Terminal window
:pdt_delete:_reply_fifo_file_
_sdomain_
_domain_
_empty_line_

Produces a listing of the entries prefixes/domains/sdomains.

Name: pdt_list

Parameters:

  • sdomain : a source domain value.
  • prefix : a prefix value
  • domain: a domain value

”.” (dot) means NULL value

The comparison operation is ‘START WITH’ — if domain is ‘a’ then all domains starting with ‘a’ are listed.

MI FIFO Command Format:

Terminal window
:pdt_list:_reply_fifo_file_
_sdomain_
_prefix_
_domain_
_empty_line_

Examples:

  • “pdt_list siph 2 .” : Lists the entries where sdomain is starting with ‘siph’, prefix is starting with ‘2’ and domain is anything
  • “pdt_list siph 2” : Lists the entries where sdomain is starting with ‘siph’, prefix is starting with ‘2’ and domain is anything
  • “pdt_list . 2 open” : Lists the entries where sdomain is anything, prefix starts with ‘2’ and domain starts with ‘open’.

Reload all sdomain-prefix-domain records from database.

Name: pdt_reload

Parameters:

  • none

MI FIFO Command Format:

Terminal window
:pdt_reload:_reply_fifo_file_
_empty_line_

Example shell scripts for MI FIFO commands are placed in ’./doc/’ (pdt_fifo_add.sh, pdt_fifo_delete.sh, pdt_fifo_list.sh).

Top contributors by DevScore(1), authored commits(2) and lines added/removed(3)

#NameDevScoreCommitsLines++Lines—
1.Elena-Ramona Modroiu781822802359
2.Elena-Ramona Modroiu611234661121
3.Bogdan-Andrei Iancu (@bogdan-iancu)55306981135
4.Daniel-Constantin Mierla (@miconda)15136138
5.Jan Janak (@janakj)14857317
6.Stefan Darius (@dariusstefan)11452361
7.Henning Westerholt (@henningw)966496
8.Andrei Pelinescu-Onciul532118
9.Ancuta Onofrei51117132
10.Razvan Crainea (@razvancrainea)421454

All remaining contributors: Anca Vamanu, Konstantin Bokarius, Edson Gellert Schubert.

(1) DevScore = author_commits + author_lines_added / (project_lines_added / project_commits) + author_lines_deleted / (project_lines_deleted / project_commits)

(2) including any documentation-related commits, excluding merge commits

(3) ignoring whitespace edits, renamed files and auto-generated files

#NameCommit Activity
1.Stefan Darius (@dariusstefan)Jun 2026 - Jul 2026
2.Razvan Crainea (@razvancrainea)Dec 2010 - Jun 2026
3.Bogdan-Andrei Iancu (@bogdan-iancu)Nov 2003 - Apr 2011
4.Anca VamanuFeb 2009 - Feb 2009
5.Elena-Ramona ModroiuOct 2005 - Jun 2008
6.Daniel-Constantin Mierla (@miconda)Jul 2006 - Mar 2008
7.Konstantin BokariusMar 2008 - Mar 2008
8.Edson Gellert SchubertFeb 2008 - Feb 2008
9.Henning Westerholt (@henningw)May 2007 - Jan 2008
10.Ancuta OnofreiSep 2007 - Sep 2007

All remaining contributors: Elena-Ramona Modroiu, Jan Janak (@janakj), Andrei Pelinescu-Onciul.

(1) including any documentation-related commits, excluding merge commits

Last edited by: Razvan Crainea (@razvancrainea), Bogdan-Andrei Iancu (@bogdan-iancu), Elena-Ramona Modroiu, Daniel-Constantin Mierla (@miconda), Konstantin Bokarius, Edson Gellert Schubert, Henning Westerholt (@henningw), Elena-Ramona Modroiu, Jan Janak (@janakj).

All documentation files (i.e. .md extension) are licensed under the Creative Common License 4.0