cpl_c Module

The following modules must be loaded before this module:

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

A SQL URL have to be given to the module for knowing where the database containing the table with CPL scripts is locates. If required a user name and password can be specified for allowing the module to connect to the database server.

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

...
modparam("cpl_c","db_url","dbdriver://username:password@dbhost/dbname")
...

Indicates the name of the table that store the CPL scripts. This table must be locate into the database specified by “db_url” parameter. For more about the format of the CPL table please see the modules/cpl_c/init.mysql file.

Default value is “cpl”.

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modparam("cpl_c","cpl_table","cpl")
...

Indicates the name of the column used for storing the username.

Default value is “username”.

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modparam("cpl_c","username_column","username")
...

Indicates the name of the column used for storing the domain.

Default value is “domain”.

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modparam("cpl_c","domain_column","domain")
...

Indicates the name of the column used for storing the the XML version of the cpl script.

Default value is “cpl_xml”.

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modparam("cpl_c","cpl_xml_column","cpl_xml")
...

Indicates the name of the column used for storing the the binary version of the cpl script (compiled version).

Default value is “cpl_bin”.

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modparam("cpl_c","cpl_bin_column","cpl_bin")
...

Points to the DTD file describing the CPL grammar. The file name may include also the path to the file. This path can be absolute or relative (be careful the path will be relative to the starting directory of OpenSIPS).

This parameter is MANDATORY!

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modparam("cpl_c","cpl_dtd_file","/etc/opensips/cpl-06.dtd")
...

Points to a directory where should be created all the log file generated by the LOG CPL node. A log file per user will be created (on demand) having the name username.log.

If this parameter is absent, the logging will be disabled without generating error on execution.

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modparam("cpl_c","log_dir","/var/log/opensips/cpl")
...

Tells for how many time is allow to have recurse for PROXY CPL node If it has value 2, when doing proxy, only twice the proxy action will be re-triggered by a redirect response; the third time, the proxy execution will end by going on REDIRECTION branch. The recurse feature can be disable by setting this parameter to 0

Default value of this parameter is 0.

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modparam("cpl_c","proxy_recurse",2)
...

Before doing proxy (forward), a script route can be executed. All modifications made by that route will be reflected only for the current branch.

Default value of this parameter is NULL (none).

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modparam("cpl_c","proxy_route", "1")
...

Tells if the username matching should be perform case sensitive or not. Set it to a non zero value to force a case sensitive handling of usernames.

Default value of this parameter is 0.

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modparam("cpl_c","case_sensitive",1)
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Defines a prefix for the domain part which should be ignored in handling users and scripts.

Default value of this parameter is empty string.

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modparam("cpl_c","realm_prefix","sip.")
...

Used by lookup tag to indicate where to perform user location. Basically this is the name of the usrloc domain (table) where the user registrations are kept.

If set to empty string, the lookup node will be disabled - no user location will be performed.

Default value of this parameter is NULL.

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modparam("cpl_c","lookup_domain","location")
...

Tells if the lookup tag should append branches (to do parallel forking) if user_location lookup returns more than one contact. Set it to a non zero value to enable parallel forking for location lookup tag.

Default value of this parameter is 0.

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modparam("cpl_c","lookup_append_branches",1)
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Indicates if the domain part of the URI should be used in user identification (otherwise only username part will be used).

Default value is “0 (disabled)”.

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modparam("cpl_c","use_domain",1)
...

Starts the execution of the CPL script. The user name is fetched from new_uri or requested uri or from To header -in this order- (for incoming execution) or from FROM header (for outgoing execution). Regarding the stateful/stateless message processing, the function is very flexible, being able to run in different modes (see below the"mode" parameter). Normally this function will end script execution. There is no guaranty that the CPL script interpretation ended when OpenSIPS script ended also (for the same INVITE ;-)) - this can happen when the CPL script does a PROXY and the script interpretation pause after proxying and it will be resume when some reply is received (this can happen in a different process of OpenSIPS).

If the function returns true to script, if value "1" is returned, the SIP server should continue with the normal behavior as if no script existed; if value (2) is returned, it means no script was found, so nothing was done.

When some error is reported (a false return code), the function itself haven't sent any SIP error reply (this can be done from script).

Meaning of the parameters is as follows:

This function can be used from REQUEST_ROUTE.

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cpl_run_script("incoming","force_stateful");
...

This function MUST be called only for REGISTER requests. It checks if the current REGISTER request is related or not with CPL script upload/download/ remove. If it is, all the needed operation will be done. For checking if the REGISTER is CPL related, the function looks fist to "Content-Type" header. If it exists and has a the mime type set to "application/cpl+xml" means this is a CPL script upload/remove operation. The distinction between to case is made by looking at "Content-Disposition" header; id its value is "script;action=store", means it's an upload; if it's "script;action=remove", means it's a remove operation; other values are considered to be errors. If no "Content-Type" header is present, the function looks to "Accept" header and if it contains the "*" or "application/cpl-xml" the request it will be consider one for downloading CPL scripts. The functions returns to script only if the REGISTER is not related to CPL. In other case, the function will send by itself the necessary replies (stateless - using sl), including for errors.

This function can be used from REQUEST_ROUTE.

...
if ($rm=="REGISTER") {
    cpl_process_register();
}
...

Same as “cpl_process_register” without internally generating the reply. All information (script) is appended to the reply but without sending it out.

Main purpose of this function is to allow integration between CPL and UserLocation services via same REGISTER messages.

This function can be used from REQUEST_ROUTE.

...
if ($rm=="REGISTER") {
    cpl_process_register();
    # continue with usrloc part
    save("location");
}
...

For the given user, loads the XML cpl file, compiles it into binary format and stores both format into database.

Name: LOAD_CPL

Parameters:

MI FIFO Command format:

                 :LOAD_CPL:_reply_fifo_file_
                 username
                 cpl_filename
                 _empty_line_

For the given user, removes the entire database record (XML cpl and binary cpl); user with empty cpl scripts are not accepted.

Name: REMOVE_CPL

Parameters:

MI FIFO Command format:

                 :REMOVE_CPL:_reply_fifo_file_
                 username
                 _empty_line_

For the given user, returns the CPL script in XML format.

Name: GET_CPL

Parameters:

MI FIFO Command format:

                 :GET_CPL:_reply_fifo_file_
                 username
                 _empty_line_

Before running OpenSIPS with cpl_c, you have to setup the database table where the module will store the CPL scripts. For that, if the table was not created by the installation script or you choose to install everything by yourself you can use the cpc-create.sql SQL script in the database directories in the opensips/scripts folder as template. Database and table name can be set with module parameters so they can be changed, but the name of the columns must be as they are in the SQL script. You can also find the complete database documentation on the project webpage, https://opensips.org/docs/db/db-schema-devel.html.