&adminguide;

- - &adminguide; - -

- Overview - - Enum module implements [i_]enum_query functions that make an enum query - based on the user part of the current Request-URI. These functions - assume that the user part consists of an international phone number - of the form +decimal-digits, where the number of digits is at - least 2 and at most 15. Out of this number - enum_query forms a domain name, - where the digits are in reverse order and separated by dots followed by - domain suffix that by default is e164.arpa.. For example, - if the user part is +35831234567, the domain - name will be 7.6.5.4.3.2.1.3.8.5.3.e164.arpa.. - i_enum_query operates in a similar - fashion. The only difference is that it adds a label (default "i") - to branch off from the default, user-ENUM tree to an infrastructure ENUM tree. - - - After forming the domain name, - enum_query queries - DNS for its NAPTR records. From the possible response - enum_query chooses those records, - whose flags field has string value "u", and whose services field has - string value "e2u+[service:]sip" or - "e2u+type[:subtype][+type[:subtype]...]" (case is ignored in both - cases), and whose regexp field is of the form !pattern!replacement!. - - - Then enum_query sorts the chosen - NAPTR records based on their <order, preference>. After sorting, - enum_query replaces the current - Request URI by applying regexp of the most preferred NAPTR record its - user part and appends to the request new branches by applying regexp of - each remaining NAPTR record to the user part of the - current Request URI. If a new URI is a tel URI, - enum_query appends to it as tel - URI parameters the value of tel_uri_params module parameter. Finally, - enum_query associates a q value - with each new URI based on the <order, preference> of the - corresponding NAPTR record. - - - When using enum_query without any - parameters, it searches for NAPTRs with service type "e2u+sip" in the - default enum tree. When using - enum_query with a single parameter, - this parameter will be used as enum tree. When using - enum_query - with two parameters, the functionality depends on the first letter in - the second parameter. When the first letter is not a '+' sign, the - second parameter will be used to search for NAPTRs with service type - "e2u+parameter:sip". When the second parameter starts with a '+' sign, - the ENUM lookup also supports compound NAPTRs - (e.g. "e2u+voice:sip+video:sip") and searching for multiple service - types within one lookup. Multiple service types must be separeted - by a '+' sign. - - - Most of the time you want to route based on the RURI. On rare occasions - you may wish to route based on something else. The function - enum_pv_query mimics the behavior - of the enum_query function except the - E.164 number in its pseudo variable argument is used for the enum lookup instead of the user - part of the RURI. Obviously the user part of the RURI is still used in the - NAPTR regexp. - - - Enum query returns 1 if the current Request URI was replaced - and -1 if not. - - - In addition to standard ENUM, support for ISN (ITAD Subscriber - Numbers) is provided as well. To allow ISN lookups to resolve, - a different formatting algorithm is expected by the DNS server. - Whereas a ENUM NAPTR record expects a DNS query of the form - 9.8.7.6.5.4.3.2.1., ISN method expects a DNS query of - the form 6.5.1212.. That is, a valid ISN number includes - a prefix of '56' in the example. The rest of the number is a - ITAD (Internet Telephony Administrative Domain) as defined - in RFCs 3872 and 2871, and as allocated by the IANA in - http://www.iana.org/assignments/trip-parameters. The ITAD is - left intact and not refersed as ENUM requires. To learn more - about ISN please refer to documents at www.freenum.org. - - - To complete a ISN lookup on the user part of the Request-URI, - isn_query() is used instead of enum_query(). - - - Enum module also implements is_from_user_enum function. - This function does an enum lookup on the from user and - returns true if found, false otherwise. - -

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- Dependencies - - The module depends on the following modules (in the other words the - listed modules must be loaded before this module): - - - No dependencies. - - - -

- -

- Exported Parameters -

- <varname>domain_suffix</varname> (string) - - The domain suffix to be added to the domain name obtained from - the digits of an E164 number. Can be overridden - by a parameter to enum_query. - - - Default value is e164.arpa. - - - Setting domain_suffix module parameter - -modparam("enum", "domain_suffix", "e1234.arpa.") - - -

- -

- <varname>tel_uri_params</varname> (string) - - A string whose contents is appended to each new tel URI in the - request as tel URI parameters. - - - - Currently &osips; does not support tel URIs. This means that at present - tel_uri_params is appended as URI parameters to every URI. - - - - Default value is - - - Setting tel_uri_params module parameter - -modparam("enum", "tel_uri_params", ";npdi") - - -

- <varname>i_enum_suffix</varname> (string) - - The domain suffix to be used for i_enum_query() lookups. - Can be overridden by a parameter to i_enum_query. - - - Default value is e164.arpa. - - - Setting i_enum_suffix module parameter - -modparam("enum", "i_enum_suffix", "e1234.arpa.") - - -

- <varname>isn_suffix</varname> (string) - - The domain suffix to be used for isn_query() lookups. Can - be overridden by a parameter to isn_query. - - - Default value is freenum.org. - - - Setting isn_suffix module parameter - -modparam("enum", "isn_suffix", "freenum.org.") - - -

- <varname>branchlabel</varname> (string) - - This parameter determines which label i_enum_query() will use - to branch off to the infrastructure ENUM tree. - - - Default value is "i" - - - Setting branchlabel module parameter - -modparam("enum", "branchlabel", "i") - - -

- <varname>bl_algorithm</varname> (string) - - This parameter determines which algorithm i_enum_query() will use - to select the position in the DNS tree where the infrastructure tree - branches off the user ENUM tree. - - - If set to "cc", i_enum_query() will always inserts the - label at the country-code level. - Examples: i.1.e164.arpa, i.3.4.e164.arpa, i.2.5.3.e164.arpa - - - If set to "txt", i_enum_query() will look for a TXT record at - [branchlabel].[reverse-country-code].[i_enum_suffix] to indicate after how many digits the - label should in inserted. - - Zone file example - -i.1.e164.arpa. IN TXT "4" -9.9.9.8.7.6.5.i.4.3.2.1.e164.arpa. IN NAPTR "NAPTR content for +1 234 5678 999" - - - - - If set to "ebl", i_enum_query() will look for an EBL (ENUM Branch Label) record at - [branchlabel].[reverse-country-code].[i_enum_suffix]. See http://www.ietf.org/internet-drafts/draft-lendl-enum-branch-location-record-00.txt for a description of that record and the - meaning of the fields. The RR type for the EBL has not been allocated yet. - This version of the code uses 65300. See resolve.h. - - Zone file example - -i.1.e164.arpa. TYPE65300 \# 14 ( - 04 ; position - 01 69 ; separator - 04 65 31 36 34 04 61 72 70 61 00 ; e164.arpa -; ) -9.9.9.8.7.6.5.i.4.3.2.1.e164.arpa. IN NAPTR "NAPTR content for +1 234 5678 999" - - - - - - Default value is cc - - - Setting the bl_algorithm module parameter - -modparam("enum", "bl_algorithm", "txt") - - -

- -

- Exported Functions -

- - <function moreinfo="none">enum_query(["suffix"[,"service"]])</function> - - - The function performs an enum query and rewrites the Request-URI with - the result of the query. See for more - information. - - Meaning of the parameters is as follows: - - - suffix - Suffix to be appended to the - domain name. - - - - service - Service string to be used in - the service field. - - - - - This function can be used from REQUEST_ROUTE. - - - <function moreinfo="none">enum_query</function> usage - -... -# search for "e2u+sip" in freenum.org -enum_query("freenum.org."); -... -# search for "e2u+sip" in default tree (configured as parameter) -enum_query(); -... -# search for "e2u+voice:sip" in e164.arpa -enum_query("e164.arpa.","voice"); -... -# search for service type "sip" or "voice:sip" or "video:sip" -# note the '+' sign in front of the second parameter -enum_query("e164.arpa.","+sip+voice:sip+video:sip"); -... -# quering for service sip and voice:sip -enum_query("e164.arpa."); -enum_query("e164.arpa.","voice"); -# or use instead -enum_query("e164.arpa.","+sip+voice:sip"); -... - - -

- -

- - <function moreinfo="none">enum_pv_query("pvar"[,"suffix"[,"service"]])</function> - - - The function performs an enum query on E.164 number stored - in its pseudo variable argument and rewrites the Request-URI with - the result of the query. See for more - information. - - Meaning of the parameters is as follows: - - - pvar - Pseudo - variable that holds an E.164 number on which enum - query is performed. - - - - suffix - Suffix to be appended to the - domain name. - - - - service - Service string to be used in - the service field. - - - - - This function can be used from REQUEST_ROUTE. - - - <function moreinfo="none">enum_pv_query</function> usage - -... -# search for "e2u+sip" in freenum.org -enum_pv_query("$avp(i:100)", "freenum.org."); -... -# search for "e2u+sip" in default tree (configured as parameter) -enum_pv_query("$fU"); -... -# search for "e2u+voice:sip" in e164.arpa -enum_pv_query("$avp(i:100)","e164.arpa.","voice"); -... -# search for service type "sip" or "voice:sip" or "video:sip" -# note the '+' sign in front of the second parameter -enum_pv_query("$fU","e164.arpa.","+sip+voice:sip+video:sip"); -... -# quering for service sip and voice:sip -enum_pv_query("$avp(i:100)","e164.arpa."); -enum_pv_query("$avp(i:100)","e164.arpa.","voice"); -# or use instead -enum_pv_query("$avp(i:100)","e164.arpa.","+sip+voice:sip"); -... - - -

- -

- - <function moreinfo="none">i_enum_query(["suffix"[,"service"]])</function> - - - The function performs an enum query and rewrites the Request-URI with - the result of the query. This the Infrastructure-ENUM version of enum_query(). - The only difference to enum_query() is in the calculation of the - FQDN where NAPTR records are looked for. - - - See ftp://ftp.rfc-editor.org/in-notes/internet-drafts/draft-haberler-carrier-enum-01.txt - for the rationale behind this function. - -

- -

- - <function moreinfo="none">isn_query(["suffix"[,"service"]])</function> - - - The function performs a ISN query and rewrites the Request-URI with - the result of the query. See for more - information. - - Meaning of the parameters is as follows: - - - suffix - Suffix to be appended to the - domain name. - - - - service - Service string to be used in - the service field. - - - - - This function can be used from REQUEST_ROUTE. - - - See ftp://ftp.ietf.org/rfc/rfc3872.txt and - ftp://ftp.ietf.org/rfc/rfc2871.txt for information - regarding the ITAD part of the ISN string. - - - <function moreinfo="none">isn_query</function> usage - -... -# search for "e2u+sip" in freenum.org -isn_query("freenum.org."); -... -# search for "e2u+sip" in default tree (configured as parameter) -isn_query(); -... -# search for "e2u+voice:sip" in freenum.org -isn_query("freenum.org.","voice"); -... - - -

- -

- <function moreinfo="none">is_from_user_enum()</function> - - Checks if the user part of from URI - is found in an enum lookup. - Returns 1 if yes and -1 if not. - - - This function can be used from REQUEST_ROUTE. - - - <function moreinfo="none">is_from_user_enum</function> usage - -... -if (is_from_user_enum()) { - .... -}; -... - - -