Domain Module

Juha Heinanen

Edited by

Juha Heinanen


Table of Contents

1. Admin Guide
1. Overview
2. Dependencies
3. Parameters
3.1. db_url (string)
3.2. domain_table (string)
3.3. domain_attrs_table (string)
3.4. did_col (string)
3.5. domain_col (string)
3.6. name_col (string)
3.7. type_col (string)
3.8. value_col (string)
3.9. register_myself (integer)
4. Functions
4.1. is_from_local()
4.2. is_uri_host_local()
4.3. is_domain_local(pseudo_variable)
4.4. lookup_domain(domain[, prefix])
5. MI Commands
5.1. domain_reload
5.2. domain_dump
6. Exported RPC Commands
6.1. domain.reload
6.2. domain.dump
7. Known Limitations
2. Developer Guide
1. Available Functions
1.1. is_domain_local(domain)

List of Examples

1.1. Setting db_url parameter
1.2. Setting domain_table parameter
1.3. Setting domain_attrs_table parameter
1.4. Setting did_col parameter
1.5. Setting domain_col parameter
1.6. Setting name_col parameter
1.7. Setting name_col parameter
1.8. Setting value_col parameter
1.9. register_myself example
1.10. is_from_local usage
1.11. is_uri_host_local usage
1.12. is_domain_local usage
1.13. lookup_domain

Chapter 1. Admin Guide

1. Overview

Domain module implements checks that based on domain table determine if a domain is “local”. A “local” domain is one that the proxy is responsible for. SIP URIs of local users must have hostpart that is equal to one of these domains.

Domain module reads the contents of domain and domain_attrs tables into cache memory when the module is loaded. Any changes in domain or domain_attrs tables must thus be followed by “domain.reload” rpc command in order to reflect them in module behavior.

Caching is implemented using a hash table. The size of the hash table is given by HASH_SIZE constant defined in domain_mod.h. Its “factory default” value is 128.

2. Dependencies

The module depends on the following modules (in the other words the listed modules must be loaded before this module):

  • database -- Any database module

3. Parameters

3.1. db_url (string)

This is URL of the database to be used.

Default value is “mysql://kamailioro:kamailioro@localhost/kamailio

Example 1.1. Setting db_url parameter

modparam("domain", "db_url", "mysql://ser:pass@db_host/ser")

3.2. domain_table (string)

Name of table containing names of local domains that the proxy is responsible for.

Default value is “domain”.

Example 1.2. Setting domain_table parameter

modparam("domain", "domain_table", "new_name")

3.3. domain_attrs_table (string)

Name of table containing attributes of local domains.

Default value is “domain_attrs”.

Example 1.3. Setting domain_attrs_table parameter

modparam("domain", "domain_attrs_table", "local_domain_attributes")

3.4. did_col (string)

Name of column containing domain id (did) of domain in domain and domain_attrs tables. In domain table, a did column value may be NULL, which means that it has same value as domain column.

Default value is “did”.

Example 1.4. Setting did_col parameter

modparam("domain", "did_col", "domain_did")

3.5. domain_col (string)

Name of column containing domain name in domain table.

Default value is “domain”.

Example 1.5. Setting domain_col parameter

modparam("domain", "domain_col", "domain_name")

3.6. name_col (string)

Name of column containing attribute name in domain_attrs table.

Default value is “name”.

Example 1.6. Setting name_col parameter

modparam("domain", "name_col", "attr_name")

3.7. type_col (string)

Name of column containing attribute type in domain_attrs table. Type value 0 is integer and type value 2 is string.

Default value is “type”.

Example 1.7. Setting name_col parameter

modparam("domain", "type_col", "attr_type")

3.8. value_col (string)

Name of column containing attribute value in domain_attrs table.

Default value is “value”.

Example 1.8. Setting value_col parameter

modparam("domain", "value_col", "attr_value")

3.9. register_myself (integer)

Register the list of domains to match 'myself' check: 0 means no myself registration, 1 means enable myself registration.

Default value is 0 (disable).

Example 1.9. register_myself example

modparam("domain", "register_myself", 1)

4. Functions

4.1. is_from_local()

Checks based on domain table if host part of From header uri is one of the local domains that the proxy is responsible for

This function can be used from REQUEST_ROUTE, FAILURE_ROUTE, BRANCH_ROUTE, and LOCAL_ROUTE.

Example 1.10. is_from_local usage

...
if (is_from_local()) {
	...
};
...

4.2. is_uri_host_local()

If called from route or failure route block, checks based on domain table if host part of Request-URI is one of the local domains that the proxy is responsible for. If called from branch route, the test is made on host part of URI of first branch, which thus must have been appended to the transaction before is_uri_host_local() is called.

This function can be used from REQUEST_ROUTE, FAILURE_ROUTE, BRANCH_ROUTE, and LOCAL_ROUTE.

Example 1.11. is_uri_host_local usage

...
if (is_uri_host_local()) {
	...
};
...

4.3. is_domain_local(pseudo_variable)

This function checks if the domain contained in the pseudo_variable is local.

This function is a generalized form of the is_from_local() and is_uri_host_local() functions, being able to completely replace them and also extends them by allowing the domain to be taken from any of the above mentioned sources. The following equivalences exist:

  • is_domain_local("$rd") is same as is_uri_host_local()

  • is_domain_local("$fd") is same as is_from_local()

This function can be used from REQUEST_ROUTE, FAILURE_ROUTE, BRANCH_ROUTE, and LOCAL_ROUTE.

Example 1.12. is_domain_local usage

...
if (is_domain_local("$rd")) {
	...
};
if (is_domain_local("$fd")) {
	...
};
if (is_domain_local("$avp(some_avp_alias)")) {
	...
};
if (is_domain_local("$avp(i:850)")) {
	...
};
if (is_domain_local("$avp(s:some_avp)")) {
	...
};
...

4.4. lookup_domain(domain[, prefix])

This function checks if domain given in domain argument (pseudo variable) is local and, if so, adds attributes associated with domain's id (did) to AVPs. If prefix argument (string) is given, names of attributes are prefixes by it. In addition to attributes given in domain_attrs table, AVP did containing did of domain is added.

This function can be used from REQUEST_ROUTE, FAILURE_ROUTE, BRANCH_ROUTE, and LOCAL_ROUTE.

Example 1.13. lookup_domain

...
if (lookup_domain("$fd", "from_")) {
    xlog("L_INFO", "did of domain $fd is $avp(from_did)\n");
}
...

5. MI Commands

5.1. domain_reload

Causes domain module to re-read the contents of domain table into cache memory.

Name: domain_reload

Parameters: none

MI FIFO Command Format:

		:domain_reload:_reply_fifo_file_
		_empty_line_

5.2. domain_dump

Causes domain module to dump hash indexes and domain names in its cache memory.

Name: domain_dump

Parameters: none

MI FIFO Command Format:

		:domain_dump:_reply_fifo_file_
		_empty_line_

6. Exported RPC Commands

6.1. domain.reload

Causes domain module to re-read the contents of domain table into cache memory.

Name: domain.reload

Parameters: none

Example:

		kamcmd domain.reload

6.2. domain.dump

Causes domain module to dump domain names in its cache memory.

Name: domain.dump

Parameters: none

Example:

		kamcmd domain.dump

7. Known Limitations

There is an unlikely race condition on domain reload. If a process uses a table, which is reloaded at the same time twice through FIFO or RPC, the second reload will delete the original table still in use by the process.

Chapter 2. Developer Guide

The module provides is_domain_local API function for use by other Kamailio modules.

1. Available Functions

1.1.  is_domain_local(domain)

Checks if domain given in str* parameter is local.

The function returns 1 if domain is local and -1 if domain is not local or if an error occurred.