registrar Module
Jan Janak
FhG FOKUS
Edited by
Jan Janak
Edited by
Bogdan-Andrei Iancu
Copyright © 2003 FhG FOKUS
Revision History
Revision $Revision: 6606 $ $Date: 2009-09-23 17:34:55 +0300
(Wed, 23 Sep 2009) $
__________________________________________________________
Table of Contents
1. Admin Guide
1.1. Overview
1.1.1. PATH support
1.2. Dependencies
1.2.1. OpenSIPS Modules
1.2.2. External Libraries or Applications
1.3. Exported Parameters
1.3.1. default_expires (integer)
1.3.2. min_expires (integer)
1.3.3. max_expires (integer)
1.3.4. default_q (integer)
1.3.5. tcp_persistent_flag (integer)
1.3.6. realm_prefix (string)
1.3.7. case_sensitive (integer)
1.3.8. received_avp (str)
1.3.9. received_param (string)
1.3.10. max_contacts (integer)
1.3.11. retry_after (integer)
1.3.12. sock_hdr_name (string)
1.4. Exported Functions
1.4.1. save(domain [,flags ,[aor]])
1.4.2. lookup(domain [, flags [, aor]])
1.4.3. registered(domain [,AOR[, callid]])
1.4.4. add_sock_hdr(hdr_name)
1.5. Exported Statistics
1.5.1. max_expires
1.5.2. max_contacts
1.5.3. defaults_expires
1.5.4. accepted_regs
1.5.5. rejected_regs
2. Frequently Asked Questions
List of Examples
1.1. Set default_expires parameter
1.2. Set min_expires parameter
1.3. Set max_expires parameter
1.4. Set default_q parameter
1.5. Set tcp_persistent_flag parameter
1.6. Set realm_prefix parameter
1.7. Set case_sensitive parameter
1.8. Set received_avp parameter
1.9. Set received_param parameter
1.10. Set max_contacts parameter
1.11. Set retry_after parameter
1.12. Set sock_hdr_namer parameter
1.13. save usage
1.14. lookup usage
1.15. registered usage
1.16. add_sock_hdr usage
Chapter 1. Admin Guide
1.1. Overview
The module contains REGISTER processing logic.
1.1.1. PATH support
Register module includes Path support (according to RFC 3327)
for usage in registrars and home-proxies.
A call to save(...) stores, if path-support is enabled in the
registrar-module, the values of the Path Header(s) along with
the contact into usrloc. There are three modes regarding the
reply to a REGISTER including one or more Path HFs:
* off - stores the value of the Path headers into usrloc
without passing it back to the UAC in the reply.
* lazy - stores the Path header and passes it back to the UAC
if Path-support is indicated by the "path" param in the
Supported HF.
* strict - rejects the registration with "420 Bad Extension"
if there's a Path header but no support for it is indicated
by the UAC. Otherwise it's stored and passed back to the
UAC.
A call to lookup(...) always uses the path header if found, and
inserts it as Route HF either in front of the first Route HF,
or after the last Via HF if no Route is present. It also sets
the destination uri to the first Path uri, thus overwriting the
received-uri, because NAT has to be handled at the
outbound-proxy of the UAC (the first hop after client's NAT).
The whole process is transparent to the user, so no config
changes are required beside setting the registrar-parameters
"use_path" and "path_mode".
1.2. Dependencies
1.2.1. OpenSIPS Modules
The following modules must be loaded before this module:
* usrloc - User Location Module.
* signaling - Signaling module.
1.2.2. External Libraries or Applications
The following libraries or applications must be installed
before running OpenSIPS with this module loaded:
* None.
1.3. Exported Parameters
1.3.1. default_expires (integer)
If the processed message contains neither Expires HFs nor
expires contact parameters, this value will be used for newly
created usrloc records. The parameter contains number of second
to expire (for example use 3600 for one hour).
Default value is 3600.
Example 1.1. Set default_expires parameter
...
modparam("registrar", "default_expires", 1800)
...
1.3.2. min_expires (integer)
The minimum expires value of a Contact, values lower than this
minimum will be automatically set to the minimum. Value 0
disables the checking.
Default value is 60.
Example 1.2. Set min_expires parameter
...
modparam("registrar", "min_expires", 60)
...
1.3.3. max_expires (integer)
The maximum expires value of a Contact, values higher than this
maximum will be automatically set to the maximum. Value 0
disables the checking.
Default value is 0.
Example 1.3. Set max_expires parameter
...
modparam("registrar", "max_expires", 120)
...
1.3.4. default_q (integer)
The parameter represents default q value for new contacts.
Because OpenSIPS doesn't support float parameter types, the
value in the parameter is divided by 1000 and stored as float.
For example, if you want default_q to be 0.38, use value 380
here.
Default value is 0.
Example 1.4. Set default_q parameter
...
modparam("registrar", "default_q", 1000)
...
1.3.5. tcp_persistent_flag (integer)
The parameter specifies the message flag to be used to control
the module behaviour regarding TCP connections. If the flag is
set for a REGISTER via TCP containing a TCP contact, the
module, via the "save()" functions will set the lifetime of the
TCP connection to the contact expire value. By doing this, the
TCP connection will stay on as long as the contact is valid.
Default value is -1 (disabled).
Example 1.5. Set tcp_persistent_flag parameter
...
modparam("registrar", "tcp_persistent_flag", 7)
...
1.3.6. realm_prefix (string)
Prefix to be automatically strip from realm. As an alternative
to SRV records (not all SIP clients support SRV lookup), a
subdomain of the master domain can be defined for SIP purposes
(like sip.mydomain.net pointing to same IP address as the SRV
record for mydomain.net). By ignoring the realm_prefix "sip.",
at registration, sip.mydomain.net will be equivalent to
mydomain.net .
Default value is NULL (none).
Example 1.6. Set realm_prefix parameter
...
modparam("registrar", "realm_prefix", "sip.")
...
1.3.7. case_sensitive (integer)
If set to 1 then AOR comparison will be case sensitive (as
RFC3261 instructs), if set to 0 then AOR comparison will be
case insensitive.
Default value is 1.
Example 1.7. Set case_sensitive parameter
...
modparam("registrar", "case_sensitive", 0)
...
1.3.8. received_avp (str)
Registrar will store the value of the AVP configured by this
parameter in the received column in the user location database.
It will leave the column empty if the AVP is empty. The AVP
should contain a SIP URI consisting of the source IP, port, and
protocol of the REGISTER message being processed.
Note
The value of this parameter should be the same as the value of
corresponding parameter of nathelper module.
Default value is "NULL" (disabled).
Example 1.8. Set received_avp parameter
...
modparam("registrar", "received_avp", "$avp(s:rcv)")
...
1.3.9. received_param (string)
The name of the parameter that will be appended to Contacts of
200 OK when the received URI was set by nathelper module.
Default value is "received".
Example 1.9. Set received_param parameter
...
modparam("registrar", "received_param", "rcv")
...
1.3.10. max_contacts (integer)
The parameter can be used to limit the number of contacts per
AOR (Address of Record) in the user location database. Value 0
disables the check.
This is the default value and will be used only if no other
value (for max_contacts) is passed as parameter to the save()
function. That's it - the function paramter overwride this
global parameter.
Default value is 0.
Example 1.10. Set max_contacts parameter
...
# Allow no more than 10 contacts per AOR
modparam("registrar", "max_contacts", 10)
...
1.3.11. retry_after (integer)
The registrar can generate 5xx reply to REGISTER in various
situations. It can, for example, happen when the max_contacts
parameter is set and the processing of REGISTER request would
exceed the limit. In this case the registrar would generate
"503 Service Unavailable" response.
If you want to add the Retry-After header field in 5xx replies,
set this parameter to a value grater than zero (0 means do not
add the header field). See section 20.33 of RFC3261 for more
details.
Default value is 0 (disabled).
Example 1.11. Set retry_after parameter
...
modparam("registrar", "retry_after", 30)
...
1.3.12. sock_hdr_name (string)
Header which contains a socket description (proto:IP:port) to
override the received socket info. The header will be search
and used only if the flag 's' (Socket header) is set at
"save()" time.
This make sens only in multiple replicated servers scenarios.
Default value is NULL.
Example 1.12. Set sock_hdr_namer parameter
...
modparam("registrar", "sock_hdr_name", "Sock-Info")
...
1.4. Exported Functions
1.4.1. save(domain [,flags ,[aor]])
The function processes a REGISTER message. It can add, remove
or modify usrloc records depending on Contact and Expires HFs
in the REGISTER message. On success, 200 OK will be returned
listing all contacts that are currently in usrloc. On an error,
error message will be send with a short description in reason
phrase.
Meaning of the parameters is as follows:
* domain - Logical domain within registrar. If database is
used then this must be name of the table which stores the
contacts.
* flags (optional)- string of the following flags:
+ 'm' (Memory only) - save the contacts only in memory
cache without no DB operation;
+ 'r' (no Reply) - do not generate a SIP reply to the
current REGISTER request.
+ 's' (Socket header) - look into REGISTER request for a
header which contains a socket description
(proto:IP:port). This socket info will be stored by
register instead of the received socket info.
+ 'cnn' (max Contacts) - this flag can be used to limit
the number of contacts for this AOR (Address of
Record) in the user location database. Value 0
disables the check. This parameter overrides the
global "max_contacts" module parameter.
+ 'f' (force registration) - this flag can be used to
force the registration of NEW contacts even if the
maximum number of contacts is reached. In such a case,
older contacts will be removed to make space to the
new ones, without exceeding the maximum allowed
number. This flag makes sense only if "cxx" is used.
+ 'p0' (Path support - 'off' mode) The Path header is
saved into usrloc, but is never included in the reply.
+ 'p1' (Path support - lazy mode) The Path header is
saved into usrloc, but is only included in the reply
if path support is indicated in the registration
request by the "path" option of the "Supported"
header.
+ 'p2' (Path support - strict mode) The path header is
only saved into usrloc, if path support is indicated
in the registration request by the "path" option of
the "Supported" header. If no path support is
indicated, the request is rejected with "420 - Bad
Extension" and the header "Unsupported: path" is
included in the reply along with the received "Path"
header. This mode is the one recommended by RFC-3327.
+ 'v' (path receiVed) if set, the "received" parameter
of the first Path URI of a registration is set as
received-uri and the NAT branch flag is set for this
contact. This is useful if the registrar is placed
behind a SIP loadbalancer, which passes the nat'ed UAC
address as "received" parameter in it's Path uri.
This parameter is a string composed of a set of flags.
* aor (optional) - Variable contain a custom AOR; if missing,
the AOR will be taken from the default place - the TO
header URI.
This function can be used from REQUEST_ROUTE.
Example 1.13. save usage
...
# save into 'location', no flags, use default AOR (TO URI)
save("location");
...
# save into 'location', do not update DB, max 5 contacts per AOR,
# use default AOR (TO URI)
save("location","mc5");
...
# save into 'location', no flags, use as AOR the FROM URI
save("location","","$fu");
...
# save into 'location',no DB update, no reply to send, take AOR from AVP
save("location","mr", "$avp(i:1)");
...
1.4.2. lookup(domain [, flags [, aor]])
The functions extracts username from Request-URI and tries to
find all contacts for the username in usrloc. If there are no
such contacts, -1 will be returned. If there are such contacts,
Request-URI will be overwritten with the contact that has the
highest q value and optionally the rest will be appended to the
message (depending on append_branches parameter value).
If the method_filtering option is enabled, the lookup function
will return only the contacts that support the method of the
processed request.
Meaning of the parameters is as follows:
* domain - Name of table that should be used for the lookup.
* flags(optional)
+ 'b' (no Branches) - this flag controls how lookup
function processes multiple contacts. If there are
multiple contacts for the given username in usrloc and
this flag is not set, Request-URI will be overwritten
with the highest-q rated contact and the rest will be
appended to sip_msg structure and can be later used by
tm for forking. If the flag is set, only Request-URI
will be overwritten with the highest-q rated contact
and the rest will be left unprocessed.
+ 'm' (Method filtering) - this flag tells if the
contact filtering based on supported methods should be
performed during lookup.
* AOR (optional)- AOR to lookup for; if missing, the RURI is
used as AOR; This can be a variable.
Return codes:
* 1 - contacts found and returned.
-1 - no contact found.
-2 - contacts found, but method not supported.
-3 - internal error during processing.
This function can be used from REQUEST_ROUTE, FAILURE_ROUTE.
Example 1.14. lookup usage
...
lookup("location"); # simple lookup
#or
lookup("location","m"); # lookup with method filtering
#or
lookup("location","","$var(aor)"); # simple lookup with AOR from PV
switch ($retcode) {
case -1:
case -3:
sl_send_reply("404", "Not Found");
exit;
case -2:
sl_send_reply("405", "Not Found");
exit;
};
...
1.4.3. registered(domain [,AOR[, callid]])
The function returns true if an AOR is registered, false
otherwise. The function does not modify the message being
process.
NOTE: if called for a reply (from onreply_route), you must pass
an AOR (as parameter), otherwise the function will fail.
Meaning of the parameters is as follows:
* domain - Name of table that should be used for the lookup.
* AOR (optional)- AOR to lookup for; if missing, the RURI is
used as AOR; This can be a variable.
* callid (optional)- callid to check if a contact if
registered with this callid (this may help you to make
distinction between newly registered contact (callid not
registered so far) and re-registration (callid already
registered).
This function can be used from REQUEST_ROUTE, FAILURE_ROUTE,
BRANCH_ROUTE, ONREPLY_ROUTE, LOCAL_ROUTE.
Example 1.15. registered usage
...
if (registered("location")) {
sl_send_reply("100", "Trying");
...
};
if (registered("location","$fu")) {
xlog("caller is registered\n");
}
...
1.4.4. add_sock_hdr(hdr_name)
Adds to the current REGISTER request a new header with
"hdr_name" which contains the description of the received
socket (proto:ip:port)
This make sens only in multiple replicated servers scenarios.
Meaning of the parameters is as follows:
* hdr_name - header name to be used.
This function can be used from REQUEST_ROUTE.
Example 1.16. add_sock_hdr usage
...
add_sock_hdr("Sock-Info");
...
1.5. Exported Statistics
1.5.1. max_expires
Value of max_expires parameter.
1.5.2. max_contacts
The value of max_contacts parameter.
1.5.3. defaults_expires
The value of default_expires parameter.
1.5.4. accepted_regs
Number of accepted registrations.
1.5.5. rejected_regs
Number of rejected registrations.
Chapter 2. Frequently Asked Questions
2.1.
What happend with the old "append_branch" module parameter?
It was removed as global option, as the "lookup" function takes
this option via the flag "b" (append Branches) See the
documentation of the "lookup" function.
2.2.
What happend with the old "method_filtering" module parameter?
It was removed as global option, as the "lookup" function takes
this option via the flag "m" (Method filtering) See the
documentation of the "lookup" function.
2.3.
What happend with the old "sock_flag" module parameter?
It was removed as global option, as the "save" function takes
this option via the flag "s" (Socket header) See the
documentation of the "save" function.
2.4.
What happend with the old "use_path" and "path_mode" module
parameters?
They were removed as global option, as the "save" function
takes these options via the flag "px" (path support) See the
documentation of the "save" function.
2.5.
What happend with the old "path_use_received" module parameter?
It was removed as global option, as the "save" function takes
this option via the flag "v" (path receiVed) See the
documentation of the "save" function.
2.6.
What happend with the old "nat_flag" module parameter?
It was removed, as the module internally loads this value from
the "USRLOC" module (see the "nat_bflag" USRLOC parameter).
2.7.
What happend with the old "use_domain" module parameter?
It was removed, as the module internally loads this option from
the "USRLOC" module. This was done in order to simplify the
configuration.
2.8.
What happend with the old "save_noreply" and "save_memory"
functions?
There functions were merged into the new "save(domain,flags)"
functions. If a reply should be sent or if the DB should be
updated also is controlled via the flags.
2.9.
Where can I find more about OpenSIPS?
Take a look at http://www.opensips.org/.
2.10.
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:
* User Mailing List -
http://lists.opensips.org/cgi-bin/mailman/listinfo/users
* Developer Mailing List -
http://lists.opensips.org/cgi-bin/mailman/listinfo/devel
E-mails regarding any stable OpenSIPS release should be sent to
<users@lists.opensips.org> and e-mails regarding development
versions should be sent to <devel@lists.opensips.org>.
If you want to keep the mail private, send it to
<users@lists.opensips.org>.
2.11.
How can I report a bug?
Please follow the guidelines provided at:
http://sourceforge.net/tracker/?group_id=232389.
2.12.
What happened to the desc_time_order parameter?
It was removed, as its functionality was mmigrate into usrloc
module, were there is a parameter with the same name.
