dialog Module


Table of Contents

1. Admin Guide
1.1. Overview
1.2. How it works
1.3. Dialog profiling
1.4. Dialog clustering
1.5. Dependencies
1.5.1. OpenSIPS Modules
1.5.2. External Libraries or Applications
1.6. Exported Parameters
1.6.1. enable_stats (integer)
1.6.2. hash_size (integer)
1.6.3. log_profile_hash_size (integer)
1.6.4. rr_param (string)
1.6.5. default_timeout (integer)
1.6.6. dlg_extra_hdrs (string)
1.6.7. dlg_match_mode (integer)
1.6.8. db_url (string)
1.6.9. db_mode (integer)
1.6.10. db_update_period (integer)
1.6.11. options_ping_interval (integer)
1.6.12. reinvite_ping_interval (integer)
1.6.13. table_name (string)
1.6.14. call_id_column (string)
1.6.15. from_uri_column (string)
1.6.16. from_tag_column (string)
1.6.17. to_uri_column (string)
1.6.18. to_tag_column (string)
1.6.19. from_cseq_column (string)
1.6.20. to_cseq_column (string)
1.6.21. from_route_column (string)
1.6.22. to_route_column (string)
1.6.23. from_contact_column (string)
1.6.24. to_contact_column (string)
1.6.25. from_sock_column (string)
1.6.26. to_sock_column (string)
1.6.27. dlg_id_column (string)
1.6.28. state_column (string)
1.6.29. start_time_column (string)
1.6.30. timeout_column (string)
1.6.31. profiles_column (string)
1.6.32. vars_column (string)
1.6.33. sflags_column (string)
1.6.34. mflags_column (string)
1.6.35. flags_column (string)
1.6.36. profiles_with_value (string)
1.6.37. profiles_no_value (string)
1.6.38. db_flush_vals_profiles (int)
1.6.39. timer_bulk_del_no (int)
1.6.40. cachedb_url (string)
1.6.41. profile_value_prefix (string)
1.6.42. profile_no_value_prefix (string)
1.6.43. profile_size_prefix (string)
1.6.44. profile_timeout (int)
1.6.45. dialog_replication_cluster (int)
1.6.46. profile_replication_cluster (int)
1.6.47. replicate_profiles_buffer (string)
1.6.48. replicate_profiles_check (string)
1.6.49. replicate_profiles_timer (string)
1.6.50. replicate_profiles_expire (string)
1.6.51. dlg_sharing_tag (string)
1.7. Exported Functions
1.7.1. create_dialog()
1.7.2. match_dialog([dlg_match_mode])
1.7.3. validate_dialog()
1.7.4. fix_route_dialog()
1.7.5. get_dialog_info(attr,var,key,key_val)
1.7.6. get_dialog_vals(names,vals,callid)
1.7.7. set_dlg_profile(profile,[value])
1.7.8. unset_dlg_profile(profile,[value])
1.7.9. is_in_profile(profile,[value])
1.7.10. get_profile_size(profile,[value],size)
1.7.11. set_dlg_flag(idx)
1.7.12. test_and_set_dlg_flag(idx, value)
1.7.13. reset_dlg_flag(idx)
1.7.14. is_dlg_flag_set(idx)
1.7.15. store_dlg_value(name,val)
1.7.16. fetch_dlg_value(name,pvar)
1.7.17. set_dlg_sharing_tag(tag_name)
1.8. Exported Statistics
1.8.1. active_dialogs
1.8.2. early_dialogs
1.8.3. processed_dialogs
1.8.4. expired_dialogs
1.8.5. failed_dialogs
1.8.6. create_sent
1.8.7. update_sent
1.8.8. delete_sent
1.8.9. create_recv
1.8.10. update_recv
1.8.11. delete_recv
1.9. Exported MI Functions
1.9.1. dlg_list
1.9.2. dlg_list_ctx
1.9.3. dlg_end_dlg
1.9.4. profile_get_size
1.9.5. profile_list_dlgs
1.9.6. profile_get_values
1.9.7. profile_end_dlgs
1.9.8. dlg_db_sync
1.9.9. dlg_cluster_sync
1.9.10. dlg_restore_db
1.9.11. list_all_profiles
1.9.12. dlg_set_sharing_tag_active
1.9.13. dlg_list_sharing_tags
1.10. Exported Pseudo-Variables
1.10.1. $DLG_count
1.10.2. $DLG_status
1.10.3. $DLG_lifetime
1.10.4. $DLG_flags
1.10.5. $DLG_dir
1.10.6. $DLG_did
1.10.7. $DLG_end_reason
1.10.8. $DLG_timeout
1.10.9. $dlg_val(name)
1.11. Exported Events
1.11.1. E_DLG_STATE_CHANGED
2. Developer Guide
2.1. Available Functions
2.1.1. register_dlgcb (dialog, type, cb, param, free_param_cb)
3. Frequently Asked Questions
4. Contributors
4.1. By Commit Statistics
4.2. By Commit Activity
5. Documentation
5.1. Contributors

List of Tables

4.1. Top contributors by DevScore(1), authored commits(2) and lines added/removed(3)
4.2. Most recently active contributors(1) to this module

List of Examples

1.1. Set enable_stats parameter
1.2. Set hash_size parameter
1.3. Set hash_size parameter
1.4. Set rr_param parameter
1.5. Set default_timeout parameter
1.6. Set dlf_extra_hdrs parameter
1.7. Set dlg_match_mode parameter
1.8. Set db_url parameter
1.9. Set db_mode parameter
1.10. Set db_update_period parameter
1.11. Set options_ping_interval parameter
1.12. Set reinvite_ping_interval parameter
1.13. Set table_name parameter
1.14. Set call_id_column parameter
1.15. Set from_uri_column parameter
1.16. Set from_tag_column parameter
1.17. Set to_uri_column parameter
1.18. Set to_tag_column parameter
1.19. Set from_cseq_column parameter
1.20. Set to_cseq_column parameter
1.21. Set from_route_column parameter
1.22. Set to_route_column parameter
1.23. Set from_contact_column parameter
1.24. Set to_contact_column parameter
1.25. Set from_sock_column parameter
1.26. Set to_sock_column parameter
1.27. Set dlg_id_column parameter
1.28. Set state_column parameter
1.29. Set start_time_column parameter
1.30. Set timeout_column parameter
1.31. Set profiles_column parameter
1.32. Set vars_column parameter
1.33. Set sflags_column parameter
1.34. Set mflags_column parameter
1.35. Set flags_column parameter
1.36. Set profiles_with_value parameter
1.37. Set profiles_no_value parameter
1.38. Set db_flush_vals_profiles parameter
1.39. Set timer_bulk_del_no parameter
1.40. Set cachedb_url parameter
1.41. Set profile_value_prefix parameter
1.42. Set profile_no_value_prefix parameter
1.43. Set profile_size_prefix parameter
1.44. Set profile_timeout parameter
1.45. Set dialog_replication_cluster parameter
1.46. Set profile_replication_cluster parameter
1.47. Set replicate_profiles_buffer parameter
1.48. Set replicate_profiles_check parameter
1.49. Set replicate_profiles_timer parameter
1.50. Set replicate_profiles_expire parameter
1.51. Set dlg_sharing_tag parameter
1.52. create_dialog() usage
1.53. match_dialog() usage
1.54. validate_dialog() usage
1.55. fix_route_dialog() usage
1.56. get_dialog_info usage
1.57. get_dialog_vals usage
1.58. set_dlg_profile usage
1.59. unset_dlg_profile usage
1.60. is_in_profile usage
1.61. get_profile_size usage
1.62. set_dlg_flag usage
1.63. test_and_set_dlg_flag usage
1.64. reset_dlg_flag usage
1.65. is_dlg_flag_set usage
1.66. store_dlg_value usage
1.67. fetch_dlg_value usage
1.68. set_dlg_sharing_tag usage

Chapter 1. Admin Guide

1.1. Overview

The dialog module provides dialog awareness to the OpenSIPS proxy. Its functionality is to keep trace of the current dialogs, to offer information about them (like how many dialogs are active).

Aside tracking, the dialog module offers functionalities like flags and attributes per dialog (persistent data across dialog), dialog profiling and dialog termination (on timeout base or external triggered).

The module, via an internal API, also provide the foundation to build on top of it more complex dialog-based functionalities via other OpenSIPS modules.

1.2. How it works

To create the dialog associated with an initial request, you must call the create_dialog() function, with or without parameter.

The dialog is automatically destroyed when a BYE is received. In case of no BYE, the dialog lifetime is controlled via the default timeout (see default_timeout - default_timeout) and custom timeout (see $DLG_timeout - $DLG_timeout).

1.3. Dialog profiling

Dialog profiling is a mechanism that helps in classifying, sorting and keeping trace of certain types of dialogs, using whatever properties of the dialog (like caller, destination, type of calls, etc). Dialogs can be dynamically added in different (and several) profile tables - logically, each profile table can have a special meaning (like dialogs outside the domain, dialogs terminated to PSTN, etc).

There are two types of profiles:

  • with no value - a dialog simply belongs to a profile. (like outbound calls profile). There is no other additional information to describe the dialog's belonging to the profile;

  • with value - a dialog belongs to a profile having a certain value (like in caller profile, where the value is the caller ID). The belonging of the dialog to the profile is strictly related to the value.

A dialog can be added to multiple profiles in the same time.

Profiles are visible (at the moment) in the request route (for initial and sequential requests) and in the branch, failure and reply routes of the original request.

Dialog profiles can also be used in distributed systems, using the OpenSIPS CacheDB Interface or the clusterer module. This feature allows you to share dialog profile information with multiple OpenSIPS instaces that use the same CacheDB backend or are part of an OpenSIPS cluster. In order to do that, the cachedb_url or profile_replication_cluster parameters must be defined. Also, the profile must be marked as shared, by adding one of the '/s' or '/b' suffixes to the name of the profile in the profiles_with_value or profiles_no_value parameters.

1.4. Dialog clustering

Dialog replication is a mechanism used to mirror all dialog changes taking place in one OpenSIPS instance to one or multiple other instances. The process is simplified by using the clusterer module which facilitates the management of a cluster of OpenSIPS nodes and the sending of replication-related BIN packets (binary-encoded, using proto_bin). This feature is useful in achieving High Availability and/or Load Balancing for ongoing calls.

Configuring both receival and sending of dialog replication packets is trivial and can be done by using the dialog_replication_cluster parameter. But in addition to just sharing data, in order to properly cluster dialogs you will need to manage which node in the cluster is doing certain actions on certain dialogs using the sharing tags mechanism. For details and configuration examples on how this would work in different usage scenarios, see this article.

The following actions will not be performed for a dialog marked with a sharing tag that is in the "backup" state:

  • sending Re-Invite or OPTIONS pings to end-points

  • generating BYE requests or any other actions(like producing CDRs) upon dialog expiration

  • sending replication packets on dialog events(update, delete)

  • counting the dialog in the profiles that it belongs; only if profile replication is also enabled

In addition to the event-driven replication, an OpenSIPS instance will first try to learn all the dialog information from antoher node in the cluster at startup. The data synchronization mechanism requires defining one of the nodes in the cluster as a "seed" node. See the clusterer module for details on how to do this and why is it needed.

In the context of dialog replication, using a database as a failsafe for obtaining restart persistency for dialog data is useful in case all nodes in the cluster are down. This approach makes the most sense if a separate, local DB is used for each node in the cluster. In consequence dialogs loaded from the database at startup are dropped and also deleted from the DB once the sync from cluster is complete. This is done for dialogs that are not reconfirmed as being active in the meantime (SIP updates, received in sync data).

Also configuring profile replication via the profile_replication_cluster parameter is not necessary when dialog replication is already configured. The profile information is included in the dialog updates sent in the dialog replication cluster. The profiles must still be marked for sharing though in the profiles_with_value or profiles_no_value parameters.

A scenario were both profile and dialog replication should be configured is when a platform has multiple POPs, where separate dialog replication clusters are configured for HA purposes, and a cluster for globally shared profiles is also required. In this case, proper counting for dialogs is ensured by using the sharing tags mechanism(in order to avoid counting each dialog twice, both on the active and backup node for that dialog).

1.5. Dependencies

1.5.1. OpenSIPS Modules

The following modules must be loaded before this module:

  • TM - Transaction module

  • RR - Record-Route module

  • clusterer - if replication_cluster parameter is set (contact replication via clusterer module)

1.5.2. External Libraries or Applications

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

  • None.

1.6. Exported Parameters

1.6.1. enable_stats (integer)

If the statistics support should be enabled or not. Via statistic variables, the module provide information about the dialog processing. Set it to zero to disable or to non-zero to enable it.

Default value is 1 (enabled).

Example 1.1. Set enable_stats parameter

...
modparam("dialog", "enable_stats", 0)
...

1.6.2. hash_size (integer)

The size of the hash table internally used to keep the dialogs. A larger table is much faster but consumes more memory. The hash size must be a power of 2 number.

IMPORTANT: If dialogs' information should be stored in a database, a constant hash_size should be used, otherwise the restored process will not take place. If you really want to modify the hash_size you must delete all table's rows before restarting OpenSIPS.

Default value is 4096.

Example 1.2. Set hash_size parameter

...
modparam("dialog", "hash_size", 1024)
...

1.6.3. log_profile_hash_size (integer)

The size of the hash table internally used to store profile->dialog associations. A larger table can provide more parallel operations but consumes more memory. The hash size is provided as the base 2 logarithm(e.g. log_profile_hash_size =4 means the table has 2^4 entries).

Default value is 4.

Example 1.3. Set hash_size parameter

...
modparam("dialog", "log_profile_hash_size", 5) #set a table size of 32
...

1.6.4. rr_param (string)

Name of the Record-Route parameter to be added with the dialog cookie. It is used for fast dialog matching of the sequential requests.

Default value is did.

Example 1.4. Set rr_param parameter

...
modparam("dialog", "rr_param", "xyz")
...

1.6.5. default_timeout (integer)

The default dialog timeout (in seconds) if no custom one is set.

Default value is 43200 (12 hours).

Example 1.5. Set default_timeout parameter

...
modparam("dialog", "default_timeout", 21600)
...

1.6.6. dlg_extra_hdrs (string)

A string containing the extra headers (full format, with EOH) to be added in the requests generated by the module (like BYEs).

Default value is NULL.

Example 1.6. Set dlf_extra_hdrs parameter

...
modparam("dialog", "dlg_extra_hdrs", "Hint: credit expired\r\n")
...

1.6.7. dlg_match_mode (integer)

How the seqential requests should be matched against the known dialogs. The modes are a combination between matching based on a cookie (DID) stored as cookie in Record-Route header and the matching based on SIP elements (as in RFC3261).

The supported modes are:

  • 0 - DID_ONLY - the match is done exclusively based on DID;

  • 1 - DID_FALLBACK - the match is first tried based on DID and if not present, it will fallback to SIP matching;

  • 2 - DID_NONE - the match is done exclusively based on SIP elements; no DID information is added in RR.

Default value is 0 (DID_ONLY).

Example 1.7. Set dlg_match_mode parameter

...
modparam("dialog", "dlg_match_mode", 1)
...

1.6.8. db_url (string)

If you want to store the information about the dialogs in a database a database url must be specified.

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

Example 1.8. Set db_url parameter

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

1.6.9. db_mode (integer)

Describe how to push into the DB the dialogs' information from memory.

The supported modes are:

  • 0 - NO_DB - the memory content is not flushed into DB;

  • 1 - REALTIME - any dialog information changes will be reflected into the database immediately.

  • 2 - DELAYED - the dialog information changes will be flushed into the DB periodically, based on a timer routine.

  • 3 - SHUTDOWN - the dialog information will be flushed into DB only at shutdown - no runtime updates.

Default value is 0.

Example 1.9. Set db_mode parameter

...
modparam("dialog", "db_mode", 1)
...

1.6.10. db_update_period (integer)

The interval (seconds) at which to update dialogs' information if you chose to store the dialogs' info at a given interval. A too short interval will generate intensive database operations, a too large one will not notice short dialogs.

Default value is 60.

Example 1.10. Set db_update_period parameter

...
modparam("dialog", "db_update_period", 120)
...

1.6.11. options_ping_interval (integer)

The interval (seconds) at which OpenSIPS will generate in-dialog OPTIONS pings for one or both of the involved parties.

Default value is 30.

Example 1.11. Set options_ping_interval parameter

...
modparam("dialog", "options_ping_interval", 20)
...

1.6.12. reinvite_ping_interval (integer)

The interval (seconds) at which OpenSIPS will generate in-dialog Re-INVITE pings for one or both of the involved parties.

Important: the ping timeout detection is performed every time this interval ticks, not when the re-INVITE transaction times out! Consequently, please make sure that the timeouts for re-INVITE transactions (e.g. the "fr_timeout" modparam of the "tm" module or its $T_fr_timeout variable) are always lower than the value of this parameter! Failing to ensure this ordering of timeouts may possibly lead to re-INVITE pings never ending a disconnected dialog due to pings getting retried before getting a chance to properly time out.

Default value is 300.

Example 1.12. Set reinvite_ping_interval parameter

...
modparam("dialog", "reinvite_ping_interval", 600)
...

1.6.13. table_name (string)

If you want to store the information about the dialogs in a database a table name must be specified.

Default value is dialog.

Example 1.13. Set table_name parameter

...
modparam("dialog", "table_name", "my_dialog")
...

1.6.14. call_id_column (string)

The column's name in the database to store the dialogs' callid.

Default value is callid.

Example 1.14. Set call_id_column parameter

...
modparam("dialog", "call_id_column", "callid_c_name")
...

1.6.15. from_uri_column (string)

The column's name in the database to store the caller's sip address.

Default value is from_uri.

Example 1.15. Set from_uri_column parameter

...
modparam("dialog", "from_uri_column", "from_uri_c_name")
...

1.6.16. from_tag_column (string)

The column's name in the database to store the From tag from the Invite request.

Default value is from_tag.

Example 1.16. Set from_tag_column parameter

...
modparam("dialog", "from_tag_column", "from_tag_c_name")
...

1.6.17. to_uri_column (string)

The column's name in the database to store the calee's sip address.

Default value is to_uri.

Example 1.17. Set to_uri_column parameter

...
modparam("dialog", "to_uri_column", "to_uri_c_name")
...

1.6.18. to_tag_column (string)

The column's name in the database to store the To tag from the 200 OK response to the Invite request, if present.

Default value is to_tag.

Example 1.18. Set to_tag_column parameter

...
modparam("dialog", "to_tag_column", "to_tag_c_name")
...

1.6.19. from_cseq_column (string)

The column's name in the database to store the cseq from caller side.

Default value is caller_cseq.

Example 1.19. Set from_cseq_column parameter

...
modparam("dialog", "from_cseq_column", "from_cseq_c_name")
...

1.6.20. to_cseq_column (string)

The column's name in the database to store the cseq from callee side.

Default value is callee_cseq.

Example 1.20. Set to_cseq_column parameter

...
modparam("dialog", "to_cseq_column", "to_cseq_c_name")
...

1.6.21. from_route_column (string)

The column's name in the database to store the route records from caller side (proxy to caller).

Default value is caller_route_set.

Example 1.21. Set from_route_column parameter

...
modparam("dialog", "from_route_column", "from_route_c_name")
...

1.6.22. to_route_column (string)

The column's name in the database to store the route records from callee side (proxy to callee).

Default value is callee_route_set.

Example 1.22. Set to_route_column parameter

...
modparam("dialog", "to_route_column", "to_route_c_name")
...

1.6.23. from_contact_column (string)

The column's name in the database to store the caller's contact uri.

Default value is caller_contact.

Example 1.23. Set from_contact_column parameter

...
modparam("dialog", "from_contact_column", "from_contact_c_name")
...

1.6.24. to_contact_column (string)

The column's name in the database to store the callee's contact uri.

Default value is callee_contact.

Example 1.24. Set to_contact_column parameter

...
modparam("dialog", "to_contact_column", "to_contact_c_name")
...

1.6.25. from_sock_column (string)

The column's name in the database to store the information about the local interface receiving the traffic from caller.

Default value is caller_sock.

Example 1.25. Set from_sock_column parameter

...
modparam("dialog", "from_sock_column", "from_sock_c_name")
...

1.6.26. to_sock_column (string)

The column's name in the database to store information about the local interface receiving the traffic from callee.

Default value is callee_sock.

Example 1.26. Set to_sock_column parameter

...
modparam("dialog", "to_sock_column", "to_sock_c_name")
...

1.6.27. dlg_id_column (string)

The column's name in the database to store the dialogs' id information.

Default value is dlg_id.

Example 1.27. Set dlg_id_column parameter

...
modparam("dialog", "dlg_id_column", "dlg_id_c_name")
...

1.6.28. state_column (string)

The column's name in the database to store the dialogs' state information.

Default value is state.

Example 1.28. Set state_column parameter

...
modparam("dialog", "state_column", "state_c_name")
...

1.6.29. start_time_column (string)

The column's name in the database to store the dialogs' start time information.

Default value is start_time.

Example 1.29. Set start_time_column parameter

...
modparam("dialog", "start_time_column", "start_time_c_name")
...

1.6.30. timeout_column (string)

The column's name in the database to store the dialogs' timeout.

Default value is timeout.

Example 1.30. Set timeout_column parameter

...
modparam("dialog", "timeout_column", "timeout_c_name")
...

1.6.31. profiles_column (string)

The column's name in the database to store the dialogs' profiles.

Default value is profiles.

Example 1.31. Set profiles_column parameter

...
modparam("dialog", "profiles_column", "profiles_c_name")
...

1.6.32. vars_column (string)

The column's name in the database to store the dialogs' vars.

Default value is vars.

Example 1.32. Set vars_column parameter

...
modparam("dialog", "vars_column", "vars_c_name")
...

1.6.33. sflags_column (string)

The column's name in the database to store the dialogs' script flags.

Default value is script_flags.

Example 1.33. Set sflags_column parameter

...
modparam("dialog", "sflags_column", "sflags_c_name")
...

1.6.34. mflags_column (string)

The column's name in the database to store the dialogs' module flags.

Default value is module_flags.

Example 1.34. Set mflags_column parameter

...
modparam("dialog", "mflags_column", "mflags_c_name")
...

1.6.35. flags_column (string)

The column's name in the database to store the dialogs' flags.

Default value is flags.

Example 1.35. Set flags_column parameter

...
modparam("dialog", "flags_column", "flags_c_name")
...

1.6.36. profiles_with_value (string)

List of names for profiles with values. Flags /b or /s allow sharing profiles between OpenSIPS instances using the clusterer module or a CacheDB backend, respectively.

Default value is empty.

Example 1.36. Set profiles_with_value parameter

...
modparam("dialog", "profiles_with_value", "caller ; my_profile; share/s; repl/b;")
...

1.6.37. profiles_no_value (string)

List of names for profiles without values. Flags /b or /s allow sharing profiles between OpenSIPS instances using the clusterer module or a CacheDB backend, respectively.

Default value is empty.

Example 1.37. Set profiles_no_value parameter

...
modparam("dialog", "profiles_no_value", "inbound ; outbound ; shared/s; repl/b;")
...

1.6.38. db_flush_vals_profiles (int)

Pushes dialog values, profiles and flags into the database along with other dialog state information (see db_mode 1 and 2).

Default value is empty.

Example 1.38. Set db_flush_vals_profiles parameter

...
modparam("dialog", "db_flush_vals_profiles", 1)
...

1.6.39. timer_bulk_del_no (int)

The number of dialogs that should be attempted to be deleted at the same time ( a single query ) from the DB back-end.

Default value is 1.

Example 1.39. Set timer_bulk_del_no parameter

...
modparam("dialog", "timer_bulk_del_no", 10)
...

1.6.40. cachedb_url (string)

Enables distributed dialog profiles and specifies the backend that should be used by the CacheDB interface.

Default value is empty.

Example 1.40. Set cachedb_url parameter

...
modparam("dialog", "cachedb_url", "redis://127.0.0.1:6379")
...

1.6.41. profile_value_prefix (string)

Specifies what prefix should be added to the profiles with value when they are inserted into CacheDB backed. This is only used when distributed profiles are enabled.

Default value is dlg_val_.

Example 1.41. Set profile_value_prefix parameter

...
modparam("dialog", "profile_value_prefix", "dlgv_")
...

1.6.42. profile_no_value_prefix (string)

Specifies what prefix should be added to the profiles without value when they are inserted into CacheDB backed. This is only used when distributed profiles are enabled.

Default value is dlg_noval_.

Example 1.42. Set profile_no_value_prefix parameter

...
modparam("dialog", "profile_no_value_prefix", "dlgnv_")
...

1.6.43. profile_size_prefix (string)

Specifies what prefix should be added to the entity that holds the profiles with value size in CacheDB backed. This is only used when distributed profiles are enabled.

Default value is dlg_size_.

Example 1.43. Set profile_size_prefix parameter

...
modparam("dialog", "profile_size_prefix", "dlgs_")
...

1.6.44. profile_timeout (int)

Specifies how long a dialog profile should be kept in the CacheDB until it expires. This is only used when distributed profiles are enabled.

Default value is 86400.

Example 1.44. Set profile_timeout parameter

...
modparam("dialog", "profile_timeout", "43200")
...

1.6.45. dialog_replication_cluster (int)

Specifies the cluster ID for dialog replication using the clusterer module. This enables sending and receiving all the dialog-related events (creation, update and deletion) in the cluster.

Default value is 0 (no replication).

Example 1.45. Set dialog_replication_cluster parameter

...
modparam("dialog", "dialog_replication_cluster", 1)
...

1.6.46. profile_replication_cluster (int)

Specifies the cluster ID for profile replication using the clusterer module. This enables sending and receiving the profile information (value, dialog count) in the cluster.

Default value is 0 (no replication).

Example 1.46. Set profile_replication_cluster parameter

...
modparam("dialog", "profile_replication_cluster", 1)
...

1.6.47. replicate_profiles_buffer (string)

Used to specify the length of the buffer used by the binary replication, in bytes. Usually this should be big enough to hold as much data as possible, but small enough to avoid UDP fragmentation. The recommended value is the smallest MTU between all the replication instances.

Default value is 1400 bytes.

Example 1.47. Set replicate_profiles_buffer parameter

...
modparam("dialog", "replicate_profiles_buffer", 500)
...

1.6.48. replicate_profiles_check (string)

Timer in seconds, used to specify how often the module should check whether old, replicated profiles values are obsolete and should be removed. should replicate its profiles to the other instances.

Default value is 10 s.

Example 1.48. Set replicate_profiles_check parameter

...
modparam("dialog", "replicate_profiles_check", 100)
...

1.6.49. replicate_profiles_timer (string)

Timer in milliseconds, used to specify how often the module should replicate its profiles to the other instances.

Default value is 10 ms.

Example 1.49. Set replicate_profiles_timer parameter

...
modparam("dialog", "replicate_profiles_timer", 100)
...

1.6.50. replicate_profiles_expire (string)

Timer in seconds, used to specify when the profiles counters received from a different instance should no longer be taken into account. This is used to prevent obsolete values, in case an instance stops replicating its counters.

Default value is 10 s.

Example 1.50. Set replicate_profiles_expire parameter

...
modparam("dialog", "replicate_profiles_expire", 10)
...

1.6.51. dlg_sharing_tag (string)

This parameter can be set(mutiple times) in order to define a sharing tag, along with its initial state, that is useful when replicating dialogs.

Format: "tag_name=state" where state may have the "active" or "backup" values.

If this parameter is not defined for a specific tag encountered at runtime (local or replicated dialog marked with that tag), it will have the initial state of backup.

For more details see the Dialog clustering chapter.

Example 1.51. Set dlg_sharing_tag parameter

...
modparam("dialog", "dlg_sharing_tag", "vip1=active")
...

1.7. Exported Functions

1.7.1.  create_dialog()

The function creats the dialog for the currently processed request. The request must be an initial request. Optionally,the function also receives a string parameter, which specifies whether the dialog end-points should be pinged via SIP options messages. The parameter can be "P" to specify to only ping the caller, "p" to only ping the callee or "Pp" to ping both dialog sides. If the extra string parameter is provided and one end-point fails to respond to a options ping, OpenSIPS will terminate the dialog from the middle. Also, the end-points can be pinged via in-dialog Re-INVITE SIP messages. This behaviour is controlled via the "R" flags for pinging the caller side, and the "r" flag for re-invite pinging the callee side. If one end-points fails to re-negotiate the session via the Re-INVITE pings, OpenSIPS will terminate the dialog from the middle The string parameter can also contain "B" to activate the bye on timeout behavior.

NOTE: both RE-INVITE and OPTIONS pinging cannot be enabled at the same time for a single dialog leg. If both flags ("PR" or "pr") are provided only RE-INVITE pinging will be used.

The function returns true if the dialog was successfully created or if the dialog was previously created.

This function can be used from REQUEST_ROUTE.

Example 1.52. create_dialog() usage

...
create_dialog();
...
#ping caller
create_dialog("P");
...
#ping caller and callee
create_dialog("Pp");

#bye on timeout
create_dialog("B");
...

1.7.2.  match_dialog([dlg_match_mode])

This function is to be used to match a sequential (in-dialog) request to an ongoing dialog.

By default, dialog matching is performed according to the dlg_match_mode module parameter. A specific matching mode may be enforced by specifying the optional "dlg_match_mode" parameter. Possible values for this parameter are "DID_ONLY", "DID_FALLBACK" and "DID_NONE".

As sequential requests are automatically matched to the dialog when doing "loose_route()" from script, this function is intended to: (A) control the place in your script where the dialog matching is done and (B) to cope with bogus sequential requests that do not have Route headers, so they are not handled by loose_route().

The function returns true if a dialog exists for the request.

This function can be used from REQUEST_ROUTE.

Example 1.53. match_dialog() usage

...
    if (has_totag()) {
        loose_route();

        # example 1: match according to dlg_match_mode
        if ($DLG_status == NULL && !match_dialog())
            xlog("cannot match request to a dialog\n");

        # example 2: override dlg_match_mode
        if ($DLG_status == NULL && !match_dialog("DID_FALLBACK"))
            xlog("cannot match request to a dialog\n");
    }
...

1.7.3.  validate_dialog()

The function checks the current received requests against the dialog (internal data) it belongs to. Performing several tests, the function will help to detect the bogus injected in-dialog requests (like malicious BYEs).

The performed tests are related to CSEQ sequence checking and routing information checking (contact and route set).

The function returns true if a dialog exists for the request and if the request is valid (according to dialog data). If the request is invalid, the following return codes are returned :

  • -1 - invalid cseq

  • -2 - invalid remote target

  • -3 - invalid route set

  • -4 - other errors ( parsing, no dlg, etc )

This function can be used from REQUEST_ROUTE.

Example 1.54. validate_dialog() usage

...
    if (has_totag()) {
        loose_route();
        if ($DLG_status!=NULL && !validate_dialog() ) {
            xlog(" in-dialog bogus request \n");
        } else {
            xlog(" in-dialog valid request - $DLG_dir !\n");
        }
    }
...

1.7.4.  fix_route_dialog()

The function forces an in dialog SIP message to contain the ruri, route headers and dst_uri, as specified by the internal data of the dialog it belongs to. The function will prevent the existence of bogus injected in-dialog requests ( like malicious BYEs )

This function can be used from REQUEST_ROUTE.

Example 1.55. fix_route_dialog() usage

...
    if (has_totag()) {
        loose_route();
        if ($DLG_status!=NULL)
            if (!validate_dialog())
                fix_route_dialog();
    }
...

1.7.5.  get_dialog_info(attr,var,key,key_val)

The function extracts a dialog value from another dialog. It first searches through all existing (ongoing) dialogs for a dialog that has a dialog variable named "key" with the value "key_val" (so a dialog where $dlg_val(key)=="key_val"). If found, it returns the value of the dialog variable "attr" from the found dialog in the "var" pseudo-variable, otherwise nothing is written in "var", and a negative error code is returned.

NOTE: the function does not require to be called in the context of a dialog - you can use it whenever / whereever for searching for other dialogs.

Meaning of the parameters is as follows:

  • attr - the name of the dialog variable (from the found dialog) to be returned;

  • var - a pvar where to store the value of the "attr" dialog variable

  • key - name of a dialog variable to be used a search key (when looking after the target dialog)

  • key_val - the value of the dialog variable that is used as key in searching the target dialog.

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

Example 1.56. get_dialog_info usage

...
if ( get_dialog_info("callee","$var(x)","caller","$fu") ) {
	xlog("caller $fU has another ongoing, talking to callee $var(x)\n")
}

# create dialog for current call and place the caller and callee attributes
create_dialog();
$dlg_val(caller) = $fu;
$dlg_val(callee) = $ru;
...

1.7.6.  get_dialog_vals(names,vals,callid)

The function fetches all the dialog variables of another dialog. It first searches through all existing (ongoing) dialogs based on the given SIP CallID. If found, it returns all the dialog variables as two parallel arrays of names and values (using the given variables "names" and "vals"). As these variables have to hold arrays, they must be AVPs.

NOTE: the function does not require to be called in the context of a dialog - you can use it whenever / whereever for searching for other dialogs.

Meaning of the parameters is as follows:

  • names - the name of an AVP variable to hold all the names of the variables from the found dialog.

  • vals - the name of an AVP variable to hold all the values of the variables from the found dialog.

  • callid - the callid of a dialog to be searched (and have the variables fetched).

This function can be used from any type of route.

Example 1.57. get_dialog_vals usage

...
if ( get_dialog_vals("$avp(d_names)","$avp(d_vals)","$var(callid)") ) {
	xlog("the call $var(callid) has the variables:\n);
	$var(i) = 0;
	while ( $(avp(d_names)[$var(i)])!=NULL ) {
		xlog("var $var(i) is $(avp(d_names)[$var(i)])='$(avp(d_vals)[$var(i)])'\n");
		$var(i) = $var(i) + 1;
	}
}
...

1.7.7.  set_dlg_profile(profile,[value])

Inserts the current dialog into a profile. Note that if the profile does not support values, this will be silently discarded. A dialog may be inserted in the same profile multiple times.

NOTE: the dialog must be created before using this function (use create_dialog() function before).

Meaning of the parameters is as follows:

  • profile - name of the profile to be added to; pseudo-variables are supported.

  • value (optional) - string value to define the belonging of the dialog to the profile - note that the profile must support values. Pseudo-variables are supported.

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

Example 1.58. set_dlg_profile usage

...
set_dlg_profile("inbound_call");
set_dlg_profile("caller","$fu");
...

1.7.8.  unset_dlg_profile(profile,[value])

Removes the current dialog from a profile.

NOTE: the dialog must be created before using this function (use create_dialog() function before).

Meaning of the parameters is as follows:

  • profile - name of the profile to be removed from; pseudo-variables are supported.

  • value (optional) - string value to define the belonging of the dialog to the profile - note that the profile must support values. Pseudo-variables are supported.

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

Example 1.59. unset_dlg_profile usage

...
unset_dlg_profile("inbound_call");
unset_dlg_profile("caller","$fu");
...

1.7.9.  is_in_profile(profile,[value])

Checks if the current dialog belongs to a profile. If the profile supports values, the check can be reinforced to take into account a specific value - if the dialog was inserted into the profile for a specific value. If no value is passed, only simply belonging of the dialog to the profile is checked. Note that if the profile does not support values, this will be silently discarded.

NOTE: the dialog must be created before using this function (use create_dialog() function before).

Meaning of the parameters is as follows:

  • profile - name of the profile to be checked against; pseudo-variables are supported.

  • value (optional) - string value to toughen the check. Pseudo-variables are supported.

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

Example 1.60. is_in_profile usage

...
if (is_in_profile("inbound_call")) {
	log("this request belongs to a inbound call\n");
}
...
if (is_in_profile("caller","XX")) {
	log("this request belongs to a call of user XX\n");
}
...

1.7.10.  get_profile_size(profile,[value],size)

Returns the number of dialogs belonging to a profile. If the profile supports values, the check can be reinforced to take into account a specific value - how many dialogs were inserted into the profile with a specific value. If not value is passed, only simply belonging of the dialog to the profile is checked. Note that the profile does not supports values, this will be silently discarded.

Meaning of the parameters is as follows:

  • profile - name of the profile to get the size for; pseudo-variables are supported.

  • value (optional) - string value to toughen the check; pseudo-variables are supported.

  • size - an AVP or script variable to return the profile size in.

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

Example 1.61. get_profile_size usage

modparam("dialog", "profiles_no_value", "inboundCalls")
modparam("dialog", "profiles_with_value", "caller")
...
get_profile_size("inboundCalls",,"$var(size)");
xlog("inboundCalls: $var(size)\n");
...
get_profile_size("caller", "$fu", "$var(size)");
xlog("currently, the user $fu has $var(size) active outgoing calls\n");
...

1.7.11.  set_dlg_flag(idx)

Sets the dialog flag index idx to true. The dialog flags are dialog persistent and they can be accessed (set and test) for all requests belonging to the dialog.

The flag index can be between 0 and 31.

NOTE: the dialog must be created before using this function (use create_dialog() function before).

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

Example 1.62. set_dlg_flag usage

...
set_dlg_flag("3");
...

1.7.12.  test_and_set_dlg_flag(idx, value)

Atomically checks if the dialog flag index idx is equal to value. If true, changes the value with the opposite one. This operation is done under the dialog lock.

The flag index can be between 0 and 31.

The value should be 0 (false) or 1 (true).

NOTE: the dialog must be created before using this function (use create_dialog() function before).

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

Example 1.63. test_and_set_dlg_flag usage

...
test_and_set_dlg_flag("3", "0");
...

1.7.13.  reset_dlg_flag(idx)

Resets the dialog flag index idx to false. The dialog flags are dialog persistent and they can be accessed (set and test) for all requests belonging to the dialog.

The flag index can be between 0 and 31.

NOTE: the dialog must be created before using this function (use create_dialog() function before).

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

Example 1.64. reset_dlg_flag usage

...
reset_dlg_flag("16");
...

1.7.14.  is_dlg_flag_set(idx)

Returns true if the dialog flag index idx is set. The dialog flags are dialog persistent and they can be accessed (set and test) for all requests belonging to the dialog.

The flag index can be between 0 and 31.

NOTE: the dialog must be created before using this function (use create_dialog() function before).

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

Example 1.65. is_dlg_flag_set usage

...
if (is_dlg_flag_set("16")) {
	xlog("dialog flag 16 is set\n");
}
...

1.7.15.  store_dlg_value(name,val)

Attaches to the dialog the value val under the name name. The values attached to dialogs are dialog persistent and they can be accessed (read and write) for all requests belonging to the dialog.

Parameter val may contain pseudo-variables.

NOTE: the dialog must be created before using this function (use create_dialog() function before).

Same functionality may be obtain by assigning a value to pseudo variable $dlg_val(name).

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

Example 1.66. store_dlg_value usage

...
store_dlg_value("inv_src_ip","$si");
store_dlg_value("account type","prepaid");
# or
$dlg_val(account_type) = "prepaid";
...

1.7.16.  fetch_dlg_value(name,pvar)

Fetches from the dialog the value of attribute named name. The values attached to dialogs are dialog persistent and they can be accessed (read and write) for all requests belonging to the dialog.

Parameter pvar may be a script var ($var) or and avp ($avp).

NOTE: the dialog must be created before using this function (use create_dialog() function before).

Same functionality may be obtain by reading the pseudo variable $dlg_val(name).

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

Example 1.67. fetch_dlg_value usage

...
fetch_dlg_value("inv_src_ip","$avp(2)");
fetch_dlg_value("account type","$var(account)");
# or
$var(account) = $dlg_val(account_type);
...

1.7.17.  set_dlg_sharing_tag(tag_name)

Marks the current dialog with the sharing tag tag_name. From this point on, actions like in-dialog pinging, BYEs on timeout etc. will depend on the tag state(no action in "backup" state, normal operation in "active" state).

If the tag is not already defined through the dlg_sharing_tag parameter and/or have it's state changed by the dlg_set_sharing_tag_active MI command, the initial state will be backup.

For more details see the Dialog clustering chapter.

NOTE: the dialog must be created before using this function (use create_dialog() function before).

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

Example 1.68. set_dlg_sharing_tag usage

...
set_dlg_sharing_tag("vip1");
...

1.8. Exported Statistics

1.8.1. active_dialogs

Returns the number of current active dialogs (may be confirmed or not).

1.8.2. early_dialogs

Returns the number of early dialogs.

1.8.3. processed_dialogs

Returns the total number of processed dialogs (terminated, expired or active) from the startup.

1.8.4. expired_dialogs

Returns the total number of expired dialogs from the startup.

1.8.5. failed_dialogs

Returns the number of failed dialogs ( dialogs were never established due to whatever reasons - internal error, negative reply, cancelled, etc )

1.8.6. create_sent

Returns the number of replicated dialog create requests send to other OpenSIPS instances.

1.8.7. update_sent

Returns the number of replicated dialog update requests send to other OpenSIPS instances.

1.8.8. delete_sent

Returns the number of replicated dialog delete requests send to other OpenSIPS instances.

1.8.9. create_recv

Returns the number of dialog create events received from other OpenSIPS instances.

1.8.10. update_recv

Returns the number of dialog update events received from other OpenSIPS instances.

1.8.11. delete_recv

Returns the number of dialog delete events received from other OpenSIPS instances.

1.9. Exported MI Functions

1.9.1.  dlg_list

Lists the description of the dialogs (calls). If no parameter is given, all dialogs will be listed. If a dialog identifier is passed as parameter (callid and fromtag), only that dialog will be listed. If a index and conter parameter is passed, it will list only a number of "counter" dialogs starting with index (as offset) - this is used to get only section of dialogs.

Name: dlg_list

Parameters (with dialog idetification):

  • callid (optional) - callid if a single dialog to be listed.

  • from_tag (optional, but cannot be present without the callid parameter) - fromtag (as per initial request) of the dialog to be listed. entry

Parameters (with dialog counting):

  • index - offset where the dialog listing should start.

  • counter - how many dialogs should be listed (starting from the offset)

MI FIFO Command Format:

		## list all ongoing dialogs
		opensipsctl fifo dlg_list
		## list the dialog by callid and From TAG
		opensipsctl fifo dlg_list abcdrssfrs122444@192.168.1.1 AAdfeEFF33
		## list 10 dialogs, starting from the position 40
		## (in the list of all ongoing dialogs)
		opensipsctl fifo dlg_list 40 10
		

1.9.2. dlg_list_ctx

The same as the dlg_list but including in the dialog description the associated context from modules sitting on top of the dialog module. This function also prints the dialog's values. In case of binary values, the non-printable chars are represented in hex (e.g. \x00)

Name: dlg_list_ctx

Parameters: see dlg_list

MI FIFO Command Format:

		opensipsctl fifo dlg_list_ctx
		

1.9.3. dlg_end_dlg

Terminates an ongoing dialog. If dialog is established, BYEs are sent in both directions. If dialog is in unconfirmed or early state, a CANCEL will be sent to the callee side, that will trigger a 487 from the callee, which, when relayed, will also end the dialog on the caller's side.

Name: dlg_end_dlg

Parameters are:

  • dialog_id - this is an identifier of the dialog - it can be either (1) the numerical unique ID of the dialog (as provided by dlg_list), either (2) the SIP Call-ID of the dialog.

  • extra_hdrs - (optional) string containg the extra headers (full format) to be added to the BYE requests.

The "dialog_id" value can be get via the "dlg_list" MI command.

MI FIFO Command Format:

		# terminate the dialog via the internal Dialog-ID
		opensipsctl fifo dlg_end_dlg 1391569858236
		# terminate the dialog via its SIP Call-ID
		opensipsctl fifo dlg_end_dlg Y2IwYjQ2YmE2ZDg5MWVkNDNkZGIwZjAzNGM1ZDY
		

1.9.4. profile_get_size

Returns the number of dialogs belonging to a profile. If the profile supports values, the check can be reinforced to take into account a specific value - how many dialogs were inserted into the profile with a specific value. If not value is passed, only simply belonging of the dialog to the profile is checked. Note that the profile does not supports values, this will be silently discarded.

Name: profile_get_size

Parameters:

  • profile - name of the profile to get the value for.

  • value (optional)- string value to toughen the check;

MI FIFO Command Format:

		opensipsctl fifo profile_get_size inbound_calls
		

1.9.5. profile_list_dlgs

Lists all the dialogs belonging to a profile. If the profile supports values, the check can be reinforced to take into account a specific value - list only the dialogs that were inserted into the profile with that specific value. If not value is passed, all dialogs belonging to the profile will be listed. Note that the profile does not supports values, this will be silently discarded. Also, when using shared profiles using the CacheDB interface, this command will only display the local dialogs.

Name: profile_list_dlgs

Parameters:

  • profile - name of the profile to list the dialog for.

  • value (optional)- string value to toughen the check;

MI FIFO Command Format:

		opensipsctl fifo profile_list_dlgs inbound_calls
		

1.9.6. profile_get_values

Lists all the values belonging to a profile along with their count. If the profile does not support values a total count will be returned. Note that this function does not work for shared profiles over the CacheDB interface.

Name: profile_get_values

Parameters:

  • profile - name of the profile to list the dialog for.

MI FIFO Command Format:

		opensipsctl fifo profile_get_values inbound_calls
		

1.9.7. profile_end_dlgs

Terminate all ongoing dialogs from a specified profile, on a single dialog it performs the same operations as the command dlg_end_dlg

Name: profile_end_dlgs

Parameters:

  • profile - name of the profile that will have its dialogs termianted

  • value - (optional) if the profile supports values terminate only the dialogs with the specified value

MI FIFO Command Format:

		opensipsctl fifo profile_end_dlgs inbound_calls
		

1.9.8. dlg_db_sync

Will synchronize the information about the dialogs from the database with the OpenSIPS internal memory. To be used mainly for transferring OpenSIPS dialog information from one server to another.

Name: dlg_db_sync

It takes no parameters

MI FIFO Command Format:

		opensipsctl fifo dlg_db_sync
		

1.9.9. dlg_cluster_sync

This command will only take effect if dialog replication is enabled.

The current node will locate a suitable donor node within the dialog_replication_cluster and issue a sync request to it. The donor node will then push all the dialog information to the current node, via the the binary interface. For dialogs that already exist in memory, the information will be not be treated as an update but discarded instead.

Name: dlg_cluster_sync

It takes no parameters

MI FIFO Command Format:

		opensipsctl fifo dlg_cluster_sync
		

1.9.10. dlg_restore_db

Restores the dialog table after a potential desynchronization event. The table is truncated, then populated with CONFIRMED dialogs from memory.

Name: dlg_restore_db

It takes no parameters

MI FIFO Command Format:

		opensipsctl fifo dlg_restore_db
		

1.9.11. list_all_profiles

Lists all the dialog profiles, along with 1 or 0 if the given profile has/does not have an associated value.

Name: list_all_profiles

Parameters: It takes no parameters

MI FIFO Command Format:

		opensipsctl fifo list_all_profiles
		

1.9.12. dlg_set_sharing_tag_active

Set the given sharing tag to the active state. The information about this change is also broadcasted in the cluster in order to force any other node that may be active on this tag to step down to backup.

For more details see the Dialog clustering chapter.

Name: dlg_set_sharing_tag_active

Parameters: tag - name of the tag to be set active

MI FIFO Command Format:

		opensipsctl fifo dlg_set_sharing_tag_active vip1
		

1.9.13. dlg_list_sharing_tags

Lists all known sharing tags and their states.

For more details on sharing tags see the Dialog clustering chapter.

Name: dlg_list_sharing_tags

Parameters: Command takes no parameters

MI FIFO Command Format:

		opensipsctl fifo dlg_list_sharing_tags
		

1.10. Exported Pseudo-Variables

1.10.1. $DLG_count

Returns the number of current active dialogs (may be confirmed or not).

1.10.2. $DLG_status

Returns the status of the dialog corresponding to the processed sequential request. This PV will be available only for sequential requests, after doing loose_route().

Value may be:

  • NULL - Dialog not found.

  • 1 - Dialog unconfirmed (created but no reply received at all)

  • 2 - Dialog in early state (created provisional reply received, but no final reply received yet)

  • 3 - Confirmed by a final reply but no ACK received yet.

  • 4 - Confirmed by a final reply and ACK received.

  • 5 - Dialog ended.

1.10.3. $DLG_lifetime

Returns the duration (in seconds) of the dialog corresponding to the processed sequential request. The duration is calculated from the dialog confirmation and the current moment. This PV will be available only for sequential requests, after doing loose_route().

NULL will be returned if there is no dialog for the request.

1.10.4. $DLG_flags

Returns the dialog flags array (as a single integer value) of the dialog corresponding to the processed sequential request. This PV will be available only for sequential requests, after doing loose_route().

NULL will be returned if there is no dialog for the request.

1.10.5. $DLG_dir

Returns the direction of the request in dialog (as "upstream" string if the request is generated by callee or "downstream" string if the request is generated by caller) - to be used for sequential request. This PV will be available only for sequential requests (not for replies), after doing loose_route().

NULL will be returned if there is no dialog for the request.

1.10.6. $DLG_did

Returns the id of the dialog corresponding to the processed sequential request. The output format is entry ':' id (as returned by the dlg_list MI function). This PV will be available only for sequential requests, after doing loose_route().

NULL will be returned if there is no dialog for the request.

1.10.7. $DLG_end_reason

Returns the reason for the dialog termination. It can be one of the following :

  • Upstream BYE - Callee has sent a BYE

  • Downstream BYE - Caller has sent a BYE

  • Lifetime Timeout - Dialog lifetime expired

  • MI Termination - Dialog ended via the MI interface

  • Ping Timeout - Dialog ended because no reply to in-dialog pings

  • RTPProxy Timeout - Media timeout signaled by RTPProxy

NULL will be returned if there is no dialog for the request, or if the dialog is not ended in the current context.

1.10.8. $DLG_timeout

Used to set the dialog lifetime (in seconds). When read, the variable returns the number of seconds until the dialog expires and is destroyed. Note that reading the variable is only possible after the dialog is created (for initial requests) or after doing loose_route() (for sequential requests). Important notice: using this variable with a REALTIME db_mode is very inefficient, because every time the dialog value is changed, a database update is done.

NULL will be returned if there is no dialog for the request, otherwise the number of seconds until the dialog expiration.

1.10.9. $dlg_val(name)

This is a read/write variable that allows access to the dialog attribute named name. This PV will be available only for sequential requests, after doing loose_route().

NULL will be returned if there is no dialog for the request.

1.11. Exported Events

1.11.1.  E_DLG_STATE_CHANGED

This event is raised when the dialog state is changed.

Parameters:

  • hash_entry - the entry in the dialog table. This is used, along with the hash_id, to uniquely identify the dialog.

  • hash_id - the id in the dialog table. This is used, along with the hash_entry, to uniquely identify the dialog.

  • callid - the callid.

  • from_tag - the From tag.

  • to_tag - the To tag.

  • old_state - the old state of the dialog.

  • new_state - the new state of the dialog.

Chapter 2. Developer Guide

2.1. Available Functions

2.1.1.  register_dlgcb (dialog, type, cb, param, free_param_cb)

Register a new callback to the dialog.

Meaning of the parameters is as follows:

  • struct dlg_cell* dlg - dialog to register callback to. If maybe NULL only for DLG_CREATED callback type, which is not a per dialog type.

  • int type - types of callbacks; more types may be register for the same callback function; only DLG_CREATED must be register alone. Possible types:

    • DLGCB_LOADED - called when a dialog is loaded from the database, or received by a node using the cluster replication.

    • DLGCB_SAVED

    • DLG_CREATED - called when a new dialog is created - it's a global type (not associated to any dialog)

    • DLG_FAILED - called when the dialog was negatively replied (non-2xx) - it's a per dialog type.

    • DLG_CONFIRMED - called when the dialog is confirmed (2xx replied) - it's a per dialog type.

    • DLG_REQ_WITHIN - called when the dialog matches a sequential request - it's a per dialog type.

    • DLG_TERMINATED - called when the dialog is terminated via BYE, or by the mi dlg_end_dlg command - it's a per dialog type.

    • DLG_EXPIRED - called when the dialog expires without receiving a BYE - it's a per dialog type. Note that when using replication sharing tags, this callback is only executed by the node that has the Active tag.

    • DLGCB_EARLY - called when the dialog is created in an early state (18x replied) - it's a per dialog type.

    • DLGCB_RESPONSE_FWDED - called when the dialog matches a reply to the initial INVITE request - it's a per dialog type.

    • DLGCB_RESPONSE_WITHIN - called when the dialog matches a reply to a subsequent in dialog request - it's a per dialog type.

    • DLGCB_MI_CONTEXT - called when the mi dlg_list_ctx command is invoked - it's a per dialog type.

    • DLGCB_DESTROY

  • dialog_cb cb - callback function to be called. Prototype is: void (dialog_cb) (struct dlg_cell* dlg, int type, struct dlg_cb_params * params);

  • void *param - parameter to be passed to the callback function.

  • param_free callback_param_free - callback function to be called to free the param. Prototype is: void (param_free_cb) (void *param);

Chapter 3. Frequently Asked Questions

3.1.

What happened with topology_hiding() function?

The respective functionality was moved into the topology_hiding module. Function prototype has remained the same.

3.2.

What happened with use_tight_match parameter?

The parameter was removed with version 1.3 as the option of tight matching became mandatory and not configurable. Now, the tight matching is done all the time (when using DID matching).

3.3.

What happened with bye_on_timeout_flag parameter?

The parameter was removed in a dialog module parameter restructuring. To keep the bye on timeout behavior, you need to provide a "B" string parameter to the create_dialog() function.

3.4.

What happened with dlg_flag parameter?

The parameter is considered obsolete. The only way to create a dialog is to call the create_dialog() function

3.5.

Where can I find more about OpenSIPS?

Take a look at https://opensips.org/.

3.6.

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 OpenSIPS 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 .

3.7.

How can I report a bug?

Please follow the guidelines provided at: https://github.com/OpenSIPS/opensips/issues.

Chapter 4. Contributors

4.1. By Commit Statistics

Table 4.1. Top contributors by DevScore(1), authored commits(2) and lines added/removed(3)

 NameDevScoreCommitsLines ++Lines --
1. Bogdan-Andrei Iancu (@bogdan-iancu)396250117492953
2. Vlad Paiu (@vladpaiu)23613461712950
3. Razvan Crainea (@razvancrainea)1781383249729
4. Liviu Chircu (@liviuchircu)1389727181044
5. Vlad Patrascu (@rvlad-patrascu)1156924481414
6. Ovidiu Sas (@ovidiusas)2822486110
7. Dan Pascu (@danpascu)2622160106
8. Eseanu Marius Cristian (@eseanucristian)196722341
9. Daniel-Constantin Mierla (@miconda)16137666
10. Henning Westerholt (@henningw)1610172187

All remaining contributors: Anca Vamanu, Ionut Ionita (@ionutrazvanionita), Andrei Dragus, Ionel Cerghit (@ionel-cerghit), Walter Doekes (@wdoekes), John Riordan, Hugues Mitonneau, Carsten Bock, Jerome Martin, Klaus Darilion, Jarrod Baumann (@jarrodb), Michel Bensoussan, Richard Revels, Elena-Ramona Modroiu, Tavis Paquette, Andrei Datcu (@andrei-datcu), Jeffrey Magder, Ron Winacott, Andy Pyles, Julián Moreno Patiño, Konstantin Bokarius, Alex Massover, Damien Sandras (@dsandras), Alex Hermann, Dusan Klinec (@ph4r05), Norman Brandinger (@NormB), UnixDev, Zero King (@l2dy), Eliot Gable, Ryan Bullock (@rrb3942), Nick Altmann (@nikbyte), 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. Regarding imported patches/code, we do our best to count the work on behalf of the proper owner, as per the "fix_authors" and "mod_renames" arrays in opensips/doc/build-contrib.sh. If you identify any patches/commits which do not get properly attributed to you, please submit a pull request which extends "fix_authors" and/or "mod_renames".

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

4.2. By Commit Activity

Table 4.2. Most recently active contributors(1) to this module

 NameCommit Activity
1. Razvan Crainea (@razvancrainea)Aug 2010 - Apr 2021
2. Bogdan-Andrei Iancu (@bogdan-iancu)Apr 2006 - Jan 2021
3. Ovidiu Sas (@ovidiusas)Feb 2008 - Sep 2020
4. Liviu Chircu (@liviuchircu)Aug 2012 - Aug 2020
5. Vlad Patrascu (@rvlad-patrascu)Jul 2016 - Jul 2020
6. Zero King (@l2dy)Mar 2020 - Mar 2020
7. Ionel Cerghit (@ionel-cerghit)Jul 2015 - Dec 2016
8. Vlad Paiu (@vladpaiu)Oct 2010 - Aug 2016
9. Jarrod Baumann (@jarrodb)Apr 2015 - Apr 2016
10. Ionut Ionita (@ionutrazvanionita)Oct 2014 - Feb 2016

All remaining contributors: Julián Moreno Patiño, Dusan Klinec (@ph4r05), Walter Doekes (@wdoekes), Eseanu Marius Cristian (@eseanucristian), Andrei Datcu (@andrei-datcu), Nick Altmann (@nikbyte), Norman Brandinger (@NormB), Damien Sandras (@dsandras), Ryan Bullock (@rrb3942), Anca Vamanu, Alex Massover, Andrei Dragus, John Riordan, Hugues Mitonneau, Richard Revels, UnixDev, Dan Pascu (@danpascu), Alex Hermann, Henning Westerholt (@henningw), Carsten Bock, Klaus Darilion, Daniel-Constantin Mierla (@miconda), Konstantin Bokarius, Edson Gellert Schubert, Jerome Martin, Tavis Paquette, Michel Bensoussan, Eliot Gable, Andy Pyles, Elena-Ramona Modroiu, Jeffrey Magder, Ron Winacott.

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

Chapter 5. Documentation

5.1. Contributors

Last edited by: Razvan Crainea (@razvancrainea), Vlad Patrascu (@rvlad-patrascu), Zero King (@l2dy), Liviu Chircu (@liviuchircu), Bogdan-Andrei Iancu (@bogdan-iancu), Julián Moreno Patiño, Ionut Ionita (@ionutrazvanionita), Vlad Paiu (@vladpaiu), Ionel Cerghit (@ionel-cerghit), Walter Doekes (@wdoekes), Eseanu Marius Cristian (@eseanucristian), Norman Brandinger (@NormB), Anca Vamanu, Andrei Dragus, Hugues Mitonneau, Klaus Darilion, Henning Westerholt (@henningw), Ovidiu Sas (@ovidiusas), Daniel-Constantin Mierla (@miconda), Konstantin Bokarius, Edson Gellert Schubert, Dan Pascu (@danpascu), Michel Bensoussan, Andy Pyles, Elena-Ramona Modroiu.

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