SipCapture Module

Alexandr Dubovikov

Edited by

Alexandr Dubovikov

Table of Contents

1. Admin Guide
1. Overview
2. Dependencies
2.1. Kamailio Modules
2.2. External Libraries or Applications
3. Parameters
3.1. db_url (str)
3.2. table_name (str)
3.3. mt_mode (str)
3.4. hash_source (str)
3.5. db_insert_mode (integer)
3.6. capture_on (integer)
3.7. capture_mode (integer)
3.8. hep_capture_on (integer)
3.9. raw_ipip_capture_on (integer)
3.10. raw_moni_capture_on (integer)
3.11. raw_socket_listen (string)
3.12. raw_interface (string)
3.13. raw_sock_children (integer)
3.14. promiscuous_on (integer)
3.15. raw_moni_bpf_on (integer)
3.16. capture_node (str)
3.17. insert_retries (integer)
3.18. insert_retry_timeout (integer)
3.19. callid_aleg_header (str)
4. MI Commands
4.1. sip_capture
5. RPC Commands
5.1. sipcapture.status param
6. Database setup
7. Limitations

List of Examples

1.1. Set db_url parameter
1.2. Set sip_capture parameter
1.3. Set mt_mode parameter
1.4. Set mt_mode parameter
1.5. db_insert_mode example
1.6. Set capture_on parameter
1.7. capture_mode example
1.8. Set hep_capture_on parameter
1.9. Set raw_ipip_capture_on parameter
1.10. Set raw_moni_capture_on parameter
1.11. Set raw_socket_listen parameter
1.12. Set raw_interface parameter
1.13. Set raw_sock_children parameter
1.14. Set promiscous_on parameter
1.15. Set raw_moni_bpf_on parameter
1.16. Set capture_node parameter
1.17. Set insert_retries parameter
1.18. Set insert_retry_timeout parameter
1.19. Set callid_aleg_header parameter

Chapter 1. Admin Guide

1. Overview

The sipcapture module stores incoming/outgoing SIP messages in database.

Kamailio can capture SIP messages in three modes

  • IPIP encapsulation. (ETHHDR+IPHDR+IPHDR+UDPHDR).

  • Monitoring/mirroring port.

  • Homer encapsulation protocol mode (HEP v1, v2, v3).

The capturing can be turned on/off using mi or rpc commands. Example:

kamctl fifo sip_capture on

kamctl fifo sip_capture off

2. Dependencies

2.1. Kamailio Modules

The following modules must be loaded before this module:

  • database module - mysql, postrgress, dbtext, unixodbc...

2.2. External Libraries or Applications

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

  • None.

3. Parameters

3.1. db_url (str)

Database URL.

Default value is "".

Example 1.1. Set db_url parameter

modparam("sipcapture", "db_url", "mysql://user:passwd@host/dbname")

3.2. table_name (str)

Name of the table's name used to store the SIP messages. Can contain multiple tables, separated by "|".

Default value is "sip_capture".

Example 1.2. Set sip_capture parameter

modparam("sipcapture", "table_name", "homer_capture")
modparam("sipcapture", "table_name", "homer_capture1|homer_capture2");

3.3. mt_mode (str)

Name of the mode used for storing data in multiple tables. Modes can be "rand" (random), "round_robin" (use a round_robin algorithm) or "hash" (use hashing to determine the table to store). These modes are only triggered if there is more than one table specified in table_name parameter, separated by "|".

Default value is "rand".

Example 1.3. Set mt_mode parameter

modparam("sipcapture", "mt_mode", "hash")

3.4. hash_source (str)

The field of the SIP message used for hashing, when mt_mode is set to "hash". The value can be "call_id", "to_user" or "from_user".

Default value is "call_id".

Example 1.4. Set mt_mode parameter

modparam("sipcapture", "hash_source", "to_user")

3.5. db_insert_mode (integer)

If set to 1, use INSERT DELAYED to store sip message into capture table when the DB driver has support for it. If no INSERT DELAYED support is offered by DB driver, then standard INSERT is used.

If set to 2, use ASYNC INSERT to store sip message into capture table when the DB driver has support for it. If no ASYNC INSERT support is offered by DB driver, then standard INSERT is used.

Default value is 0 (no INSERT DELAYED).

Example 1.5. db_insert_mode example

modparam("sipcapture", "db_insert_mode", 1)

3.6. capture_on (integer)

Parameter to enable/disable capture globaly (on(1)/off(0))

Default value is "0".

Example 1.6. Set capture_on parameter

modparam("sipcapture", "capture_on", 1)

3.7. capture_mode (integer)

This parameter can be used for defining a capture mode which can be used in the sip_capture calls as a parameter. A capture mode has a name and some parameters. It must be defined in the format: name=>param1=val1;param2=val2;... The parameters are db_url, table_name, mt_mode and hash_source (optional). Multiple capture modes can be defined by using this parameter multiple times. After this, the capture modes can be used like: sip_capture ("", "CAPTURE_MODE");

Example 1.7. capture_mode example

modparam("sipcapture", "capture_mode", "mode1=>db_url=mysql://user:passwd@host/dbname1;table_name=homer_capture1|homer_capture2;mt_mode=hash;hash_source=call_id;")
modparam("sipcapture", "capture_mode", "mode2=>db_url=mysql://user:passwd@host/dbname2;table_name=homer_capture3|homer_capture4;mt_mode=rand;")

3.8. hep_capture_on (integer)

Parameter to enable/disable capture of HEP (on(1)/off(0))

Default value is "0".

Example 1.8. Set hep_capture_on parameter

modparam("sipcapture", "hep_capture_on", 1)

3.9. raw_ipip_capture_on (integer)

Parameter to enable/disable IPIP capturing (on(1)/off(0))

Default value is "0".

Example 1.9. Set raw_ipip_capture_on parameter

modparam("sipcapture", "raw_ipip_capture_on", 1)

3.10. raw_moni_capture_on (integer)

Parameter to enable/disable monitoring/mirroring port capturing (on(1)/off(0)) Only one mode on raw socket can be enabled! Monitoring port capturing currently supported only on Linux.

Default value is "0".

Example 1.10. Set raw_moni_capture_on parameter

modparam("sipcapture", "raw_moni_capture_on", 1)

3.11. raw_socket_listen (string)

Parameter indicate an listen IP address of RAW socket for IPIP capturing. You can also define a port/portrange for IPIP/Mirroring mode, to capture SIP messages in specific ports:

"" - the source/destination port of the SIP message must be equal 5060

"" - the source/destination port of the SIP message must be equal or be between 5060 and 5090.

The port/portrange must be defined if you are planning to use mirroring capture! In this case, the part with IP address will be ignored, but to make parser happy, use i.e.

Default value is "".

Example 1.11. Set raw_socket_listen parameter

modparam("sipcapture", "raw_socket_listen", "")
modparam("sipcapture", "raw_socket_listen", "")

3.12. raw_interface (string)

Name of the interface to bind on the raw socket.

Default value is "".

Example 1.12. Set raw_interface parameter

modparam("sipcapture", "raw_interface", "eth0")

3.13. raw_sock_children (integer)

Parameter define how many children that must be created to listen the raw socket.

Default value is "1".

Example 1.13. Set raw_sock_children parameter

modparam("sipcapture", "raw_sock_children", 6)

3.14. promiscuous_on (integer)

Parameter to enable/disable promiscuous mode on the raw socket. Linux only.

Default value is "0".

Example 1.14. Set promiscous_on parameter

modparam("sipcapture", "promiscuous_on", 1)

3.15. raw_moni_bpf_on (integer)

Activate Linux Socket Filter (LSF based on BPF) on the mirroring interface. The structure is defined in linux/filter.h. The default LSF accept a port/portrange from the raw_socket_listen param. Currently LSF supported only on Linux.

Default value is "0".

Example 1.15. Set raw_moni_bpf_on parameter

modparam("sipcapture", "raw_moni_bpf_on", 1)

3.16. capture_node (str)

Name of the capture node.

Default value is "homer01".

Example 1.16. Set capture_node parameter

modparam("sipcapture", "capture_node", "homer03")

3.17. insert_retries (integer)

The number of times Kamailio should retry to write to the Homer database in case the first attempt failed. The retry is also limited timewise by the insert_retry_timeout parameter. Values allowed range from 0 to 500.

Default value is 0 (no retries).

Example 1.17. Set insert_retries parameter

modparam("sipcapture", "insert_retries", 5)

3.18. insert_retry_timeout (integer)

The time limit in seconds Kamailio retries to write to the Homer database in case the first attempt failed. This parameter is only used together with the insert_retries parameter. Values allowed range from 0 to 300.

Default value is 60 seconds.

Example 1.18. Set insert_retry_timeout parameter

modparam("sipcapture", "insert_retry_timeout", 10)

3.19. callid_aleg_header (str)

Header name used to correlate A-leg with B-leg. It can take a list of headers, separated by semicolon, e.g. "X-CID0;X-CID1". First match wins.

Default value is "X-CID".

Example 1.19. Set callid_aleg_header parameter

modparam("sipcapture", "callid_aleg_header", "X-CallIDALeg")

4. MI Commands

4.1.  sip_capture

Name: sip_capture


  • capture_mode : turns on/off SIP message capturing. Possible values are:

    • on

    • off

    The parameter is optional - if missing, the command will return the status of the SIP message capturing (as string on or off ) without changing anything.

MI FIFO Command Format:


5. RPC Commands

5.1.  sipcapture.status param

Name: sipcapture.status


  • on or off: turns on/off SIP message capturing. Possible values are:

    • on

    • off

  • check does not change sipcapture status, just reports the current status.

6. Database setup

Before running Kamailio with the sipcapture module, you have to setup the database tables where the module will store the data. For that, if the table were not created by the installation script or you choose to install everything by yourself you can use the sipcapture_create.sql, SQL script in the sql folder of sipcapture module as template. You can also find the complete database documentation on the project webpage,

7. Limitations

  • 1. Only one capturing mode on RAW socket is supported: IPIP or monitoring/mirroring port. Don't activate both at the same time.
  • 2. By default MySQL doesn't support INSERT DELAYED for partitioning table. You can patch MySQL (
  • 3. Mirroring port capturing works only on Linux.