pdt Module

Elena-Ramona Modroiu

Edited by

Elena-Ramona Modroiu


Table of Contents
1. User's Guide
1.1. Overview
1.2. Dependencies
1.2.1. OpenSER Modules
1.2.2. External Libraries or Applications
1.3. Exported Parameters
1.3.1. db_url (string)
1.3.2. db_table (string)
1.3.3. sdomain_column (string)
1.3.4. prefix_column (string)
1.3.5. domain_column (string)
1.3.6. prefix (string)
1.3.7. hsize_2pow (integer)
1.3.8. sync_time (integer)
1.3.9. clean_time (integer)
1.4. Exported Functions
1.4.1. prefix2domain(rewrite_mode, multidomain_mode)
1.4.2. prefix2domain(rewrite_mode)
1.4.3. prefix2domain()
1.5. Exported MI Functions
1.5.1. pdt_add
1.5.2. pdt_delete
1.5.3. pdt_list
1.6. Installation & Running
2. Developer's Guide
3. Frequently Asked Questions
List of Examples
1-1. prefix-domain translation
1-2. Set db_url parameter
1-3. Set db_table parameter
1-4. Set sdomain_column parameter
1-5. Set prefix_column parameter
1-6. Set domain_column parameter
1-7. Set prefix parameter
1-8. Set hsize_2pow parameter
1-9. Set sync_time parameter
1-10. Set clean_time parameter
1-11. prefix2domain usage

Chapter 1. User's Guide

1.1. Overview

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.

<prefix><userid><:password>@<mydomain.com> ...

and the result will be:

<userid><:password>@<domain[:port]>...

Example 1-1. 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 and the MySQL script to create the database needed by PDT are located in './doc/'.

  • 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).


1.2. Dependencies

1.2.1. OpenSER Modules

The following modules must be loaded before this module:

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


1.2.2. External Libraries or Applications

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

  • None.


1.3. Exported Parameters

1.3.1. db_url (string)

SQL URL of database--username, password, host, port and database (ex: mysql://username:password@hostname.com/database)

Default value is "mysql://root@127.0.0.1/pdt".

Example 1-2. Set db_url parameter

...
modparam("pdt", "db_url", "mysql://user:xxx@127.0.0.1/ser")
...

1.3.2. db_table (string)

Table name.

Default value is "pdt".

Example 1-3. Set db_table parameter

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

1.3.3. sdomain_column (string)

Name of 'sdomain' column.

Default value is "sdomain".

Example 1-4. Set sdomain_column parameter

...
modparam("pdt", "domain_column", "source_domain")
...

1.3.4. prefix_column (string)

Name of 'prefix' column.

Default value is "prefix".

Example 1-5. Set prefix_column parameter

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

1.3.5. domain_column (string)

Name of 'domain' column.

Default value is "domain".

Example 1-6. Set domain_column parameter

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

1.3.6. prefix (string)

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.

Example 1-7. Set prefix parameter

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

1.3.7. hsize_2pow (integer)

Number of the hash entries = 2^hash_size.

Default value is 4.

Example 1-8. Set hsize_2pow parameter

...
modparam("pdt", "hsize_2pow", 4)
...

1.3.8. sync_time (integer)

Time in seconds to synchronize the cache of each process with the changes made through FIFO. Any prefix-domain change made through FIFO is guaranteed to have efect after this period of time past.

Default value is 600.

Example 1-9. Set sync_time parameter

...
modparam("pdt", "sync_time", 300)
...

1.3.9. clean_time (integer)

Time in seconds to clean the changes inserted via FIFO. The changes will be removed from FIFO diff list only when all OpenSER processes applied these changes.

Default value is 900.

Example 1-10. Set clean_time parameter

...
modparam("pdt", "clean_time", 600)
...

1.4. Exported Functions

1.4.1. 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. If the parameter is missing or it has the value "0", then the prefix is removed along with the leading prefix. If the value is "1", only the leading prefix is removed. If the values is "2" the user part of the URI is not changed.

The "multidomain_mode" parameter specifies the kind of multidomain support to use. There are three possible values:

  • 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.

This function can be used from REQUEST_ROUTE, FAILURE_ROUTE.

Example 1-11. prefix2domain usage

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

1.4.2. prefix2domain(rewrite_mode)

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

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

1.4.3. prefix2domain()

The same as prefix2domain("0", "0").

...
prefix2domain();
...

1.5. Exported MI Functions

The modules uses only the cache to look up domains. If you want to add or delete a new prefix-domain pair you have to use MI FIFO commands. All changes made via these commands are applied to database, while the database is loaded only at OpenSER start up time.


1.5.1. pdt_add

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:

		:pdt_add:_reply_fifo_file_
		_sdomain_
		_prefix_
		_domain_
		_empty_line_
		

1.5.2. pdt_delete

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:

		:pdt_delete:_reply_fifo_file_
		_sdomain_
		_domain_
		_empty_line_
		

1.5.3. pdt_list

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:

		: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'.


1.6. Installation & Running

Make sure you have created the table needed by this module.

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


Chapter 2. Developer's Guide

The module does not provide any API to use in other OpenSER modules.


Chapter 3. Frequently Asked Questions

3.1. Where can I find more about OpenSER?
3.2. Where can I post a question about this module?
3.3. How can I report a bug?

3.1. Where can I find more about OpenSER?

3.2. Where can I post a question about this module?

First at all check if your question was already answered on one of our mailing lists:

E-mails regarding any stable OpenSER release should be sent to and e-mails regarding development versions should be sent to .

If you want to keep the mail private, send it to .

3.3. How can I report a bug?

Please follow the guidelines provided at: http://sourceforge.net/tracker/?group_id=139143.