1diameter(3) Erlang Module Definition diameter(3)
2
6 diameter - Main API of the diameter application.
7
9 This module provides the interface with which a user can implement a
10 Diameter node that sends and receives messages using the Diameter pro‐
11 tocol as defined in RFC 6733.
12 Basic usage consists of creating a representation of a locally imple‐
14 mented Diameter node and its capabilities with start_service/2, adding
15 transport capability using add_transport/2 and sending Diameter re‐
16 quests and receiving Diameter answers with call/4. Incoming Diameter
17 requests are communicated as callbacks to a diameter_app(3) callback
18 modules as specified in the service configuration.
19 Beware the difference between diameter (not capitalized) and Diameter
21 (capitalized). The former refers to the Erlang application named diame‐
22 ter whose main api is defined here, the latter to Diameter protocol in
23 the sense of RFC 6733.
24 The diameter application must be started before calling most functions
26 in this module.
27
29 Address():
30 DiameterIdentity():
33 Grouped():
36 OctetString():
39 Time():
42 Unsigned32():
45 UTF8String():
48 Types corresponding to RFC 6733 AVP Data Formats. Defined in diame‐
49 ter_dict(4).
50 application_alias() = term():
52 Name identifying a Diameter application in service configuration.
53 Passed to call/4 when sending requests defined by the application.
54 application_module() = Mod | [Mod | ExtraArgs] | #diameter_call‐
56 back{}:
57 Mod = atom()
60 ExtraArgs = list()
61 Module implementing the callback interface defined in diame‐
64 ter_app(3), along with any extra arguments to be appended to those
65 documented. Note that extra arguments specific to an outgoing re‐
66 quest can be specified to call/4, in which case those are appended
67 to any module-specific extra arguments.
68 Specifying a #diameter_callback{} record allows individual func‐
70 tions to be configured in place of the usual diameter_app(3) call‐
71 backs. See diameter_callback.erl for details.
72 application_opt():
74 Options defining a Diameter application. Has one of the following
75 types.
76 {alias, application_alias()}:
78 Unique identifier for the application in the scope of the ser‐
79 vice. Defaults to the value of the dictionary option.
80 {dictionary, atom()}:
82 Name of an encode/decode module for the Diameter messages defined
83 by the application. These modules are generated from files whose
84 format is documented in diameter_dict(4).
85 {module, application_module()}:
87 Callback module in which messages of the Diameter application are
88 handled. See diameter_app(3) for the required interface and se‐
89 mantics.
90 {state, term()}:
92 Initial callback state. The prevailing state is passed to some
93 diameter_app(3) callbacks, which can then return a new state. De‐
94 faults to the value of the alias option.
95 {call_mutates_state, true|false}:
97 Whether or not the pick_peer/4 application callback can modify
98 the application state. Defaults to false.
99 Warning:
101 pick_peer/4 callbacks are serialized when this option is true,
102 which is a potential performance bottleneck. A simple Diameter
103 client may suffer no ill effects from using mutable state but a
104 server or agent that responds to incoming request should probably
105 avoid it.
106 {answer_errors, callback|report|discard}:
109 Manner in which incoming answer messages containing decode errors
110 are handled.
111 If callback then errors result in a handle_answer/4 callback in
113 the same fashion as for handle_request/3, with errors communi‐
114 cated in the errors field of the #diameter_packet{} passed to the
115 callback. If report then an answer containing errors is discarded
116 without a callback and a warning report is written to the log. If
117 discard then an answer containing errors is silently discarded
118 without a callback. In both the report and discard cases the re‐
119 turn value for the call/4 invocation in question is as if a call‐
120 back had taken place and returned {error, failure}.
121 Defaults to discard.
123 {request_errors, answer_3xxx|answer|callback}:
125 Manner in which incoming requests are handled when an error other
126 than 3007 (DIAMETER_APPLICATION_UNSUPPORTED, which cannot be as‐
127 sociated with an application callback module), is detected.
128 If answer_3xxx then requests are answered without a handle_re‐
130 quest/3 callback taking place. If answer then even 5xxx errors
131 are answered without a callback unless the connection in question
132 has configured the RFC 3588 common dictionary as noted below. If
133 callback then a handle_request/3 callback always takes place and
134 its return value determines the answer sent to the peer, if any.
135 Defaults to answer_3xxx.
137 Note:
139 Answers sent by diameter set the E-bit in the Diameter Header.
140 Since RFC 3588 allows only 3xxx result codes in an answer-message,
141 answer has the same semantics as answer_3xxx when the transport in
142 question has been configured with diameter_gen_base_rfc3588 as its
143 common dictionary. Since RFC 6733 allows both 3xxx and 5xxx result
144 codes in an answer-message, a transport with diame‐
145 ter_gen_base_rfc6733 as its common dictionary does distinguish be‐
146 tween answer_3xxx and answer.
147 call_opt():
150 Options available to call/4 when sending an outgoing Diameter re‐
151 quest. Has one of the following types.
152 {extra, list()}:
154 Extra arguments to append to callbacks to the callback module in
155 question. These are appended to any extra arguments configured on
156 the callback itself. Multiple options append to the argument
157 list.
158 {filter, peer_filter()}:
160 Filter to apply to the list of available peers before passing it
161 to the pick_peer/4 callback for the application in question. Mul‐
162 tiple options are equivalent a single all filter on the corre‐
163 sponding list of filters. Defaults to none.
164 {peer, diameter_app:peer_ref()}:
166 Peer to which the request in question can be sent, preempting the
167 selection of peers having advertised support for the Diameter ap‐
168 plication in question. Multiple options can be specified, and
169 their order is respected in the candidate lists passed to a sub‐
170 sequent pick_peer/4 callback.
171 {timeout, Unsigned32()}:
173 Number of milliseconds after which the request should timeout.
174 Defaults to 5000.
175 detach:
177 Cause call/4 to return ok as soon as the request in question has
178 been encoded, instead of waiting for and returning the result
179 from a subsequent handle_answer/4 or handle_error/4 callback.
180 An invalid option will cause call/4 to fail.
182 capability():
184 AVP values sent in outgoing CER or CEA messages during capabilities
185 exchange. Can be configured both on a service and a transport, val‐
186 ues on the latter taking precedence. Has one of the following
187 types.
188 {'Origin-Host', DiameterIdentity()}:
190 {'Origin-Realm', DiameterIdentity()}:
193 {'Host-IP-Address', [Address()]}:
196 An address list is available to the start function of a transport
197 module, which can return a new list for use in the subsequent CER
198 or CEA. Host-IP-Address need not be specified if the transport
199 module in question communicates an address list as described in
200 diameter_transport(3)
201 {'Vendor-Id', Unsigned32()}:
203 {'Product-Name', UTF8String()}:
206 {'Origin-State-Id', Unsigned32()}:
209 Origin-State-Id is optional but, if configured, will be included
210 in outgoing CER/CEA and DWR/DWA messages. Setting a value of 0
211 (zero) is equivalent to not setting a value, as documented in RFC
212 6733. The function origin_state_id/0 can be used as to retrieve a
213 value that is computed when the diameter application is started.
214 {'Supported-Vendor-Id', [Unsigned32()]}:
216 {'Auth-Application-Id', [Unsigned32()]}:
219 {'Inband-Security-Id', [Unsigned32()]}:
222 Inband-Security-Id defaults to the empty list, which is equiva‐
223 lent to a list containing only 0 (NO_INBAND_SECURITY). If 1 (TLS)
224 is specified then TLS is selected if the CER/CEA received from
225 the peer offers it.
226 {'Acct-Application-Id', [Unsigned32()]}:
228 {'Vendor-Specific-Application-Id', [Grouped()]}:
231 {'Firmware-Revision', Unsigned32()}:
234 Note that each tuple communicates one or more AVP values. It is an
237 error to specify duplicate tuples.
238 eval() = {M,F,A} | fun() | [eval() | A]:
240 An expression that can be evaluated as a function in the following
241 sense.
242 eval([{M,F,A} | T]) ->
244 apply(M, F, T ++ A);
245 eval([[F|A] | T]) ->
246 eval([F | T ++ A]);
247 eval([F|A]) ->
248 apply(F, A);
249 eval(F) ->
250 eval([F]).
251 Applying an eval() E to an argument list A is meant in the sense of
254 eval([E|A]).
255 Warning:
257 Beware of using fun expressions of the form fun Name/Arity in situa‐
258 tions in which the fun is not short-lived and code is to be upgraded
259 at runtime since any processes retaining such a fun will have a ref‐
260 erence to old code. In particular, such a value is typically inappro‐
261 priate in configuration passed to start_service/2 or add_transport/2.
262 peer_filter() = term():
265 Filter passed to call/4 in order to select candidate peers for a
266 pick_peer/4 callback. Has one of the following types.
267 none:
269 Matches any peer. This is a convenience that provides a filter
270 equivalent to no filter.
271 host:
273 Matches only those peers whose Origin-Host has the same value as
274 Destination-Host in the outgoing request in question, or any peer
275 if the request does not contain a Destination-Host AVP.
276 realm:
278 Matches only those peers whose Origin-Realm has the same value as
279 Destination-Realm in the outgoing request in question, or any
280 peer if the request does not contain a Destination-Realm AVP.
281 {host, any|DiameterIdentity()}:
283 Matches only those peers whose Origin-Host has the specified
284 value, or all peers if the atom any.
285 {realm, any|DiameterIdentity()}:
287 Matches only those peers whose Origin-Realm has the specified
288 value, or all peers if the atom any.
289 {eval, eval()}:
291 Matches only those peers for which the specified eval() returns
292 true when applied to the connection's diameter_caps record. Any
293 other return value or exception is equivalent to false.
294 {neg, peer_filter()}:
296 Matches only those peers not matched by the specified filter.
297 {all, [peer_filter()]}:
299 Matches only those peers matched by each filter in the specified
300 list.
301 {any, [peer_filter()]}:
303 Matches only those peers matched by at least one filter in the
304 specified list. The resulting list will be in match order, peers
305 matching the first filter of the list sorting before those
306 matched by the second, and so on.
307 {first, [peer_filter()]}:
309 Like any, but stops at the first filter for which there are
310 matches, which can be much more efficient when there are many
311 peers. For example, the following filter causes only peers best
312 matching both the host and realm filters to be presented.
313 {first, [{all, [host, realm]}, realm]}
315 An invalid filter is equivalent to {any,[]}, a filter that matches
318 no peer.
319 Note:
321 The host and realm filters cause the Destination-Host and Destina‐
322 tion-Realm AVPs to be extracted from the outgoing request, assuming
323 it to be a record- or list-valued diameter_codec:message(), and as‐
324 suming at most one of each AVP. If this is not the case then the
325 {host|realm, DiameterIdentity()} filters must be used to achieve the
326 desired result. An empty DiameterIdentity() (which should not be typ‐
327 ical) matches all hosts/realms for the purposes of filtering.
328 Warning:
331 A host filter is not typically desirable when setting Destination-
332 Host since it will remove peer agents from the candidates list.
333 service_event() = #diameter_event{service = service_name(), info =
336 service_event_info()}:
337 An event message sent to processes that have subscribed to these
338 using subscribe/1.
339 service_event_info() = term():
341 The info field of a service_event() record. Can have one of the
342 following types.
343 start:
345 stop:
348 The service is being started or stopped. No event precedes a
349 start event. No event follows a stop event, and this event im‐
350 plies the termination of all transport processes.
351 {up, Ref, Peer, Config, Pkt}:
353 {up, Ref, Peer, Config}:
356 {down, Ref, Peer, Config}:
359 Ref = transport_ref()
362 Peer = diameter_app:peer()
363 Config = {connect|listen, [transport_opt()]}
364 Pkt = #diameter_packet{}
365 The RFC 3539 watchdog state machine has transitioned into (up) or
368 out of (down) the OKAY state. If a #diameter_packet{} is present
369 in an up event then there has been a capabilities exchange on a
370 newly established transport connection and the record contains
371 the received CER or CEA.
372 Note that a single up or down event for a given peer corresponds
374 to multiple peer_up/3 or peer_down/3 callbacks, one for each of
375 the Diameter applications negotiated during capabilities ex‐
376 change. That is, the event communicates connectivity with the
377 peer as a whole while the callbacks communicate connectivity with
378 respect to individual Diameter applications.
379 {reconnect, Ref, Opts}:
381 Ref = transport_ref()
384 Opts = [transport_opt()]
385 A connecting transport is attempting to establish/reestablish a
388 transport connection with a peer following connect_timer or
389 watchdog_timer expiry.
390 {closed, Ref, Reason, Config}:
392 Ref = transport_ref()
395 Config = {connect|listen, [transport_opt()]}
396 Capabilities exchange has failed. Reason can have one of the fol‐
399 lowing types.
400 {'CER', Result, Caps, Pkt}:
402 Result = ResultCode | {capabilities_cb, CB, ResultCode|discard}
405 Caps = #diameter_caps{}
406 Pkt = #diameter_packet{}
407 ResultCode = integer()
408 CB = eval()
409 An incoming CER has been answered with the indicated result
412 code, or discarded. Caps contains pairs of values, for the lo‐
413 cal node and remote peer respectively. Pkt contains the CER in
414 question. In the case of rejection by a capabilities callback,
415 the tuple contains the rejecting callback.
416 {'CER', Caps, {ResultCode, Pkt}}:
418 ResultCode = integer()
421 Caps = #diameter_caps{}
422 Pkt = #diameter_packet{}
423 An incoming CER contained errors and has been answered with the
426 indicated result code. Caps contains values for the local node
427 only. Pkt contains the CER in question.
428 {'CER', timeout}:
430 An expected CER was not received within capx_timeout of connec‐
431 tion establishment.
432 {'CEA', Result, Caps, Pkt}:
434 Result = ResultCode | atom() | {capabilities_cb, CB, ResultCode|discard}
437 Caps = #diameter_caps{}
438 Pkt = #diameter_packet{}
439 ResultCode = integer()
440 An incoming CEA has been rejected for the indicated reason. An
443 integer-valued Result indicates the result code sent by the
444 peer. Caps contains pairs of values for the local node and re‐
445 mote peer. Pkt contains the CEA in question. In the case of re‐
446 jection by a capabilities callback, the tuple contains the re‐
447 jecting callback.
448 {'CEA', Caps, Pkt}:
450 Caps = #diameter_caps{}
453 Pkt = #diameter_packet{}
454 An incoming CEA contained errors and has been rejected. Caps
457 contains only values for the local node. Pkt contains the CEA
458 in question.
459 {'CEA', timeout}:
461 An expected CEA was not received within capx_timeout of connec‐
462 tion establishment.
463 {watchdog, Ref, PeerRef, {From, To}, Config}:
465 Ref = transport_ref()
468 PeerRef = diameter_app:peer_ref()
469 From, To = initial | okay | suspect | down | reopen
470 Config = {connect|listen, [transport_opt()]}
471 An RFC 3539 watchdog state machine has changed state.
474 any():
476 For forward compatibility, a subscriber should be prepared to re‐
477 ceive info fields of forms other than the above.
478 service_name() = term():
480 Name of a service as passed to start_service/2 and with which the
481 service is identified. There can be at most one service with a
482 given name on a given node. Note that erlang:make_ref/0 can be used
483 to generate a service name that is somewhat unique.
484 service_opt():
486 Option passed to start_service/2. Can be any capability() as well
487 as the following.
488 {application, [application_opt()]}:
490 A Diameter application supported by the service.
491 A service must configure one tuple for each Diameter application
493 it intends to support. For an outgoing request, the relevant ap‐
494 plication_alias() is passed to call/4, while for an incoming re‐
495 quest the application identifier in the message header determines
496 the application, the identifier being specified in the applica‐
497 tion's dictionary file.
498 Warning:
500 The capabilities advertised by a node must match its configured ap‐
501 plications. In particular, application configuration must be
502 matched by corresponding capability() configuration, of *-Applica‐
503 tion-Id AVPs in particular.
504 {decode_format, record | list | map | none}:
507 The format of decoded messages and grouped AVPs in the msg field
508 of diameter_packet records and value field of diameter_avp
509 records respectively. If record then a record whose definition is
510 generated from the dictionary file in question. If list or map
511 then a [Name | Avps] pair where Avps is a list of AVP name/values
512 pairs or a map keyed on AVP names respectively. If none then the
513 atom-value message name, or undefined for a Grouped AVP. See also
514 diameter_codec:message().
515 Defaults to record.
517 Note:
519 AVPs are decoded into a list of diameter_avp records in avps field
520 of diameter_packet records independently of decode_format.
521 {restrict_connections, false | node | nodes | [node()] | eval()}:
524 The degree to which the service allows multiple transport connec‐
525 tions to the same peer, as identified by its Origin-Host at capa‐
526 bilities exchange.
527 If [node()] then a connection is rejected if another already ex‐
529 ists on any of the specified nodes. Types false, node, nodes and
530 eval() are equivalent to [], [node()], [node()|nodes()] and the
531 evaluated value respectively, evaluation of each expression tak‐
532 ing place whenever a new connection is to be established. Note
533 that false allows an unlimited number of connections to be estab‐
534 lished with the same peer.
535 Multiple connections are independent and governed by their own
537 peer and watchdog state machines.
538 Defaults to nodes.
540 {sequence, {H,N} | eval()}:
542 A constant value H for the topmost 32-N bits of of 32-bit End-to-
543 End and Hop-by-Hop Identifiers generated by the service, either
544 explicitly or as a return value of a function to be evaluated at
545 start_service/2. In particular, an identifier Id is mapped to a
546 new identifier as follows.
547 (H bsl N) bor (Id band ((1 bsl N) - 1))
549 Note that RFC 6733 requires that End-to-End Identifiers remain
552 unique for a period of at least 4 minutes and that this and the
553 call rate places a lower bound on appropriate values of N: at a
554 rate of R requests per second, an N-bit counter traverses all of
555 its values in (1 bsl N) div (R*60) minutes, so the bound is
556 4*R*60 =< 1 bsl N.
557 N must lie in the range 0..32 and H must be a non-negative inte‐
559 ger less than 1 bsl (32-N).
560 Defaults to {0,32}.
562 Warning:
564 Multiple Erlang nodes implementing the same Diameter node should be
565 configured with different sequence masks to ensure that each node
566 uses a unique range of End-to-End and Hop-by-Hop Identifiers for
567 outgoing requests.
568 {share_peers, boolean() | [node()] | eval()}:
571 Nodes to which peer connections established on the local Erlang
572 node are communicated. Shared peers become available in the re‐
573 mote candidates list passed to pick_peer/4 callbacks on remote
574 nodes whose services are configured to use them: see
575 use_shared_peers below.
576 If false then peers are not shared. If [node()] then peers are
578 shared with the specified list of nodes. If eval() then peers are
579 shared with the nodes returned by the specified function, evalu‐
580 ated whenever a peer connection becomes available or a remote
581 service requests information about local connections. The value
582 true is equivalent to fun erlang:nodes/0. The value node() in a
583 list is ignored, so a collection of services can all be config‐
584 ured to share with the same list of nodes.
585 Defaults to false.
587 Note:
589 Peers are only shared with services of the same name for the pur‐
590 pose of sending outgoing requests. Since the value of the applica‐
591 tion_opt() alias, passed to call/4, is the handle for identifying a
592 peer as a suitable candidate, services that share peers must use
593 the same aliases to identify their supported applications. They
594 should typically also configure identical capabilities(), since by
595 sharing peer connections they are distributing the implementation
596 of a single Diameter node across multiple Erlang nodes.
597 {strict_arities, boolean() | encode | decode}:
600 Whether or not to require that the number of AVPs in a message or
601 grouped AVP agree with those specified in the dictionary in ques‐
602 tion when passing messages to diameter_app(3) callbacks. If true
603 then mismatches in an outgoing messages cause message encoding to
604 fail, while mismatches in an incoming message are reported as
605 5005/5009 errors in the errors field of the diameter_packet
606 record passed to handle_request/3 or handle_answer/4 callbacks.
607 If false then neither error is enforced/detected. If encode or
608 decode then errors are only enforced/detected on outgoing or in‐
609 coming messages respectively.
610 Defaults to true.
612 Note:
614 Disabling arity checks affects the form of messages at encode/de‐
615 code. In particular, decoded AVPs are represented as lists of val‐
616 ues, regardless of the AVP's arity (ie. expected number in the mes‐
617 sage/AVP grammar in question), and values are expected to be sup‐
618 plied as lists at encode. This differs from the historic decode be‐
619 haviour of representing AVPs of arity 1 as bare values, not wrapped
620 in a list.
621 {string_decode, boolean()}:
624 Whether or not to decode AVPs of type OctetString() and its de‐
625 rived types DiameterIdentity(), DiameterURI(), IPFilterRule(),
626 QoSFilterRule(), and UTF8String(). If true then AVPs of these
627 types are decoded to string(). If false then values are retained
628 as binary().
629 Defaults to true.
631 Warning:
633 This option should be set to false since a sufficiently malicious
634 peer can otherwise cause large amounts of memory to be consumed
635 when decoded Diameter messages are passed between processes. The
636 default value is for backwards compatibility.
637 {traffic_counters, boolean()}:
640 Whether or not to count application-specific messages; those for
641 which diameter_app(3) callbacks take place. If false then only
642 messages handled by diameter itself are counted: CER/CEA,
643 DWR/DWA, DPR/DPA.
644 Defaults to true.
646 Note:
648 Disabling counters is a performance improvement, but means that the
649 omitted counters are not returned by service_info/2.
650 {use_shared_peers, boolean() | [node()] | eval()}:
653 Nodes from which communicated peers are made available in the re‐
654 mote candidates list of pick_peer/4 callbacks.
655 If false then remote peers are not used. If [node()] then only
657 peers from the specified list of nodes are used. If eval() then
658 only peers returned by the specified function are used, evaluated
659 whenever a remote service communicates information about an
660 available peer connection. The value true is equivalent to fun
661 erlang:nodes/0. The value node() in a list is ignored.
662 Defaults to false.
664 Note:
666 A service that does not use shared peers will always pass the empty
667 list as the second argument of pick_peer/4 callbacks.
668 Warning:
671 Sending a request over a peer connection on a remote node is less
672 efficient than sending it over a local connection. It may be
673 preferable to make use of the service_opt() restrict_connections
674 and maintain a dedicated connection on each node from which re‐
675 quests are sent.
676 transport_opt():
679 Any transport option except applications, capabilities, trans‐
680 port_config, and transport_module. Used as defaults for transport
681 configuration, values passed to add_transport/2 overriding values
682 configured on the service.
683 transport_opt():
685 Option passed to add_transport/2. Has one of the following types.
686 {applications, [application_alias()]}:
688 Diameter applications to which the transport should be re‐
689 stricted. Defaults to all applications configured on the service
690 in question. Applications not configured on the service in ques‐
691 tion are ignored.
692 Warning:
694 The capabilities advertised by a node must match its configured ap‐
695 plications. In particular, setting applications on a transport typ‐
696 ically implies having to set matching *-Application-Id AVPs in a
697 capabilities() tuple.
698 {avp_dictionaries, [module()]}:
701 A list of alternate dictionary modules with which to encode/de‐
702 code AVPs that are not defined by the dictionary of the applica‐
703 tion in question. At decode, such AVPs are represented as diame‐
704 ter_avp records in the 'AVP' field of a decoded message or
705 Grouped AVP, the first alternate that succeeds in decoding the
706 AVP setting the record's value field. At encode, values in an
707 'AVP' list can be passed as AVP name/value 2-tuples, and it is an
708 encode error for no alternate to define the AVP of such a tuple.
709 Defaults to the empty list.
711 Note:
713 The motivation for alternate dictionaries is RFC 7683, Diameter
714 Overload Indication Conveyance (DOIC), which defines AVPs to be
715 piggybacked onto existing application messages rather than defining
716 an application of its own. The DOIC dictionary is provided by the
717 diameter application, as module diameter_gen_doic_rfc7683, but al‐
718 ternate dictionaries can be used to encode/decode any set of AVPs
719 not known to an application dictionary.
720 {capabilities, [capability()]}:
723 AVPs used to construct outgoing CER/CEA messages. Values take
724 precedence over any specified on the service in question.
725 Specifying a capability as a transport option may be particularly
727 appropriate for Inband-Security-Id, in case TLS is desired over
728 TCP as implemented by diameter_tcp(3).
729 {capabilities_cb, eval()}:
731 Callback invoked upon reception of CER/CEA during capabilities
732 exchange in order to ask whether or not the connection should be
733 accepted. Applied to the transport_ref() and #diameter_caps{}
734 record of the connection.
735 The return value can have one of the following types.
737 ok:
739 Accept the connection.
740 integer():
742 Causes an incoming CER to be answered with the specified Re‐
743 sult-Code.
744 discard:
746 Causes an incoming CER to be discarded without CEA being sent.
747 unknown:
749 Equivalent to returning 3010, DIAMETER_UNKNOWN_PEER.
750 Returning anything but ok or a 2xxx series result code causes the
752 transport connection to be broken. Multiple capabilities_cb op‐
753 tions can be specified, in which case the corresponding callbacks
754 are applied until either all return ok or one does not.
755 {capx_timeout, Unsigned32()}:
757 Number of milliseconds after which a transport process having an
758 established transport connection will be terminated if the ex‐
759 pected capabilities exchange message (CER or CEA) is not received
760 from the peer. For a connecting transport, the timing of connec‐
761 tion attempts is governed by connect_timer or watchdog_timer ex‐
762 piry. For a listening transport, the peer determines the timing.
763 Defaults to 10000.
765 {connect_timer, Tc}:
767 Tc = Unsigned32()
770 For a connecting transport, the RFC 6733 Tc timer, in millisec‐
773 onds. This timer determines the frequency with which a transport
774 attempts to establish an initial connection with its peer follow‐
775 ing transport configuration. Once an initial connection has been
776 established, watchdog_timer determines the frequency of reconnec‐
777 tion attempts, as required by RFC 3539.
778 For a listening transport, the timer specifies the time after
780 which a previously connected peer will be forgotten: a connection
781 after this time is regarded as an initial connection rather than
782 reestablishment, causing the RFC 3539 state machine to pass to
783 state OKAY rather than REOPEN. Note that these semantics are not
784 governed by the RFC and that a listening transport's con‐
785 nect_timer should be greater than its peer's Tw plus jitter.
786 Defaults to 30000 for a connecting transport and 60000 for a lis‐
788 tening transport.
789 {disconnect_cb, eval()}:
791 Callback invoked prior to terminating the transport process of a
792 transport connection having watchdog state OKAY. Applied to ap‐
793 plication|service|transport and the transport_ref() and diame‐
794 ter_app:peer() in question: application indicates that the diame‐
795 ter application is being stopped, service that the service in
796 question is being stopped by stop_service/1, and transport that
797 the transport in question is being removed by remove_transport/2.
798 The return value can have one of the following types.
800 {dpr, [option()]}:
802 Send Disconnect-Peer-Request to the peer, the transport process
803 being terminated following reception of Disconnect-Peer-Answer
804 or timeout. An option() can be one of the following.
805 {cause, 0|rebooting|1|busy|2|goaway}:
807 Disconnect-Cause to send, REBOOTING, BUSY and
808 DO_NOT_WANT_TO_TALK_TO_YOU respectively. Defaults to reboot‐
809 ing for Reason=service|application and goaway for Rea‐
810 son=transport.
811 {timeout, Unsigned32()}:
813 Number of milliseconds after which the transport process is
814 terminated if DPA has not been received. Defaults to the
815 value of dpa_timeout.
816 dpr:
818 Equivalent to {dpr, []}.
819 close:
821 Terminate the transport process without Disconnect-Peer-Request
822 being sent to the peer.
823 ignore:
825 Equivalent to not having configured the callback.
826 Multiple disconnect_cb options can be specified, in which case
828 the corresponding callbacks are applied until one of them returns
829 a value other than ignore. All callbacks returning ignore is
830 equivalent to not having configured them.
831 Defaults to a single callback returning dpr.
833 {dpa_timeout, Unsigned32()}:
835 Number of milliseconds after which a transport connection is ter‐
836 minated following an outgoing DPR if DPA is not received.
837 Defaults to 1000.
839 {dpr_timeout, Unsigned32()}:
841 Number of milliseconds after which a transport connection is ter‐
842 minated following an incoming DPR if the peer does not close the
843 connection.
844 Defaults to 5000.
846 {incoming_maxlen, 0..16777215}:
848 Bound on the expected size of incoming Diameter messages. Mes‐
849 sages larger than the specified number of bytes are discarded.
850 Defaults to 16777215, the maximum value of the 24-bit Message
852 Length field in a Diameter Header.
853 {length_errors, exit|handle|discard}:
855 How to deal with errors in the Message Length field of the Diame‐
856 ter Header in an incoming message. An error in this context is
857 that the length is not at least 20 bytes (the length of a
858 Header), is not a multiple of 4 (a valid length) or is not the
859 length of the message in question, as received over the transport
860 interface documented in diameter_transport(3).
861 If exit then the transport process in question exits. If handle
863 then the message is processed as usual, a resulting handle_re‐
864 quest/3 or handle_answer/4 callback (if one takes place) indicat‐
865 ing the 5015 error (DIAMETER_INVALID_MESSAGE_LENGTH). If discard
866 then the message in question is silently discarded.
867 Defaults to exit.
869 Note:
871 The default value reflects the fact that a transport module for a
872 stream-oriented transport like TCP may not be able to recover from
873 a message length error since such a transport must use the Message
874 Length header to divide the incoming byte stream into individual
875 Diameter messages. An invalid length leaves it with no reliable way
876 to rediscover message boundaries, which may result in the failure
877 of subsequent messages. See diameter_tcp(3) for the behaviour of
878 that module.
879 {pool_size, pos_integer()}:
882 Number of transport processes to start. For a listening trans‐
883 port, determines the size of the pool of accepting transport pro‐
884 cesses, a larger number being desirable for processing multiple
885 concurrent peer connection attempts. For a connecting transport,
886 determines the number of connections to the peer in question that
887 will be attempted to be establshed: the service_opt(): re‐
888 strict_connections should also be configured on the service in
889 question to allow multiple connections to the same peer.
890 {spawn_opt, [term()] | {M,F,A}}:
892 An options list passed to erlang:spawn_opt/2 to spawn a handler
893 process for an incoming Diameter request on the local node, or an
894 MFA that returns the pid of a handler process.
895 Options monitor and link are ignored in the list-valued case. An
897 MFA is applied with an additional term prepended to its argument
898 list, and should return either the pid of the handler process
899 that invokes diameter_traffic:request/1 on the argument in order
900 to process the request, or the atom discard. The handler process
901 need not be local, and diameter need not be started on the remote
902 node, but diameter and relevant application callbacks must be on
903 the code path.
904 Defaults to the empty list.
906 {strict_capx, boolean()]}:
908 Whether or not to enforce the RFC 6733 requirement that any mes‐
909 sage before capabilities exchange should close the peer connec‐
910 tion. If false then unexpected messages are discarded.
911 Defaults to true. Changing this results in non-standard behav‐
913 iour, but can be useful in case peers are known to be behave
914 badly.
915 {strict_mbit, boolean()}:
917 Whether or not to regard an AVP setting the M-bit as erroneous
918 when the command grammar in question does not explicitly allow
919 the AVP. If true then such AVPs are regarded as 5001 errors, DI‐
920 AMETER_AVP_UNSUPPORTED. If false then the M-bit is ignored and
921 policing it becomes the receiver's responsibility.
922 Defaults to true.
924 Warning:
926 RFC 6733 is unclear about the semantics of the M-bit. One the one
927 hand, the CCF specification in section 3.2 documents AVP in a com‐
928 mand grammar as meaning any arbitrary AVP; on the other hand, 1.3.4
929 states that AVPs setting the M-bit cannot be added to an existing
930 command: the modified command must instead be placed in a new Diam‐
931 eter application.
932 The reason for the latter is presumably interoperability: allowing
934 arbitrary AVPs setting the M-bit in a command makes its interpreta‐
935 tion implementation-dependent, since there's no guarantee that all
936 implementations will understand the same set of arbitrary AVPs in
937 the context of a given command. However, interpreting AVP in a com‐
938 mand grammar as any AVP, regardless of M-bit, renders 1.3.4 mean‐
939 ingless, since the receiver can simply ignore any AVP it thinks
940 isn't relevant, regardless of the sender's intent.
941 Beware of confusing mandatory in the sense of the M-bit with manda‐
943 tory in the sense of the command grammar. The former is a semantic
944 requirement: that the receiver understand the semantics of the AVP
945 in the context in question. The latter is a syntactic requirement:
946 whether or not the AVP must occur in the message in question.
947 {transport_config, term()}:
950 {transport_config, term(), Unsigned32() | infinity}:
953 Term passed as the third argument to the start/3 function of the
954 relevant transport module in order to start a transport process.
955 Defaults to the empty list.
956 The 3-tuple form additionally specifies an interval, in millisec‐
958 onds, after which a started transport process should be termi‐
959 nated if it has not yet established a connection. For example,
960 the following options on a connecting transport request a connec‐
961 tion with one peer over SCTP or another (typically the same) over
962 TCP.
963 {transport_module, diameter_sctp}
965 {transport_config, SctpOpts, 5000}
966 {transport_module, diameter_tcp}
967 {transport_config, TcpOpts}
968 To listen on both SCTP and TCP, define one transport for each.
971 {transport_module, atom()}:
973 Module implementing a transport process as defined in diame‐
974 ter_transport(3). Defaults to diameter_tcp.
975 Multiple transport_module and transport_config options are al‐
977 lowed. The order of these is significant in this case (and only
978 in this case), a transport_module being paired with the first
979 transport_config following it in the options list, or the default
980 value for trailing modules. Transport starts will be attempted
981 with each of the modules in order until one establishes a connec‐
982 tion within the corresponding timeout (see below) or all fail.
983 {watchdog_config, [{okay|suspect, non_neg_integer()}]}:
985 Configuration that alters the behaviour of the watchdog state ma‐
986 chine. On key okay, the non-negative number of answered DWR mes‐
987 sages before transitioning from REOPEN to OKAY. On key suspect,
988 the number of watchdog timeouts before transitioning from OKAY to
989 SUSPECT when DWR is unanswered, or 0 to not make the transition.
990 Defaults to [{okay, 3}, {suspect, 1}]. Not specifying a key is
992 equivalent to specifying the default value for that key.
993 Warning:
995 The default value is as required by RFC 3539: changing it results
996 in non-standard behaviour that should only be used to simulate mis‐
997 behaving nodes during test.
998 {watchdog_timer, TwInit}:
1001 TwInit = Unsigned32()
1004 | {M,F,A}
1005 The RFC 3539 watchdog timer. An integer value is interpreted as
1008 the RFC's TwInit in milliseconds, a jitter of +/- 2 seconds being
1009 added at each rearming of the timer to compute the RFC's Tw. An
1010 MFA is expected to return the RFC's Tw directly, with jitter ap‐
1011 plied, allowing the jitter calculation to be performed by the
1012 callback.
1013 An integer value must be at least 6000 as required by RFC 3539.
1015 Defaults to 30000.
1016 Unrecognized options are silently ignored but are returned unmodi‐
1018 fied by service_info/2 and can be referred to in predicate func‐
1019 tions passed to remove_transport/2.
1020 transport_ref() = reference():
1022 Reference returned by add_transport/2 that identifies the configu‐
1023 ration.
1024
1026 add_transport(SvcName, {connect|listen, [Opt]}) -> {ok, Ref} | {error,
1027 Reason}
1028 Types:
1030 SvcName = service_name()
1032 Opt = transport_opt()
1033 Ref = transport_ref()
1034 Reason = term()
1035 Add transport capability to a service.
1037 The service will start transport processes as required in order
1039 to establish a connection with the peer, either by connecting to
1040 the peer (connect) or by accepting incoming connection requests
1041 (listen). A connecting transport establishes transport connec‐
1042 tions with at most one peer, an listening transport potentially
1043 with many.
1044 The diameter application takes responsibility for exchanging
1046 CER/CEA with the peer. Upon successful completion of capabili‐
1047 ties exchange the service calls each relevant application mod‐
1048 ule's peer_up/3 callback after which the caller can exchange Di‐
1049 ameter messages with the peer over the transport. In addition to
1050 CER/CEA, the service takes responsibility for the handling of
1051 DWR/DWA and required by RFC 3539, as well as for DPR/DPA.
1052 The returned reference uniquely identifies the transport within
1054 the scope of the service. Note that the function returns before
1055 a transport connection has been established.
1056 Note:
1058 It is not an error to add a transport to a service that has not
1059 yet been configured: a service can be started after configuring
1060 its transports.
1061 call(SvcName, App, Request, [Opt]) -> Answer | ok | {error, Reason}
1064 Types:
1066 SvcName = service_name()
1068 App = application_alias()
1069 Request = diameter_codec:message()
1070 Answer = term()
1071 Opt = call_opt()
1072 Send a Diameter request message.
1074 App specifies the Diameter application in which the request is
1076 defined and callbacks to the corresponding callback module will
1077 follow as described below and in diameter_app(3). Unless the de‐
1078 tach option is specified, the call returns either when an answer
1079 message is received from the peer or an error occurs. In the an‐
1080 swer case, the return value is as returned by a handle_answer/4
1081 callback. In the error case, whether or not the error is re‐
1082 turned directly by diameter or from a handle_error/4 callback
1083 depends on whether or not the outgoing request is successfully
1084 encoded for transmission to the peer, the cases being documented
1085 below.
1086 If there are no suitable peers, or if pick_peer/4 rejects them
1088 by returning false, then {error,no_connection} is returned. Oth‐
1089 erwise pick_peer/4 is followed by a prepare_request/3 callback,
1090 the message is encoded and then sent.
1091 There are several error cases which may prevent an answer from
1093 being received and passed to a handle_answer/4 callback:
1094 * If the initial encode of the outgoing request fails, then
1096 the request process fails and {error,encode} is returned.
1097 * If the request is successfully encoded and sent but the an‐
1099 swer times out then a handle_error/4 callback takes place
1100 with Reason = timeout.
1101 * If the request is successfully encoded and sent but the ser‐
1103 vice in question is stopped before an answer is received
1104 then a handle_error/4 callback takes place with Reason =
1105 cancel.
1106 * If the transport connection with the peer goes down after
1108 the request has been sent but before an answer has been re‐
1109 ceived then an attempt is made to resend the request to an
1110 alternate peer. If no such peer is available, or if the sub‐
1111 sequent pick_peer/4 callback rejects the candidates, then a
1112 handle_error/4 callback takes place with Reason = failover.
1113 If a peer is selected then a prepare_retransmit/3 callback
1114 takes place, after which the semantics are the same as fol‐
1115 lowing an initial prepare_request/3 callback.
1116 * If an encode error takes place during retransmission then
1118 the request process fails and {error,failure} is returned.
1119 * If an application callback made in processing the request
1121 fails (pick_peer, prepare_request, prepare_retransmit, han‐
1122 dle_answer or handle_error) then either {error,encode} or
1123 {error,failure} is returned depending on whether or not
1124 there has been an attempt to send the request over the
1125 transport.
1126 Note that {error,encode} is the only return value which guaran‐
1128 tees that the request has not been sent over the transport con‐
1129 nection.
1130 origin_state_id() -> Unsigned32()
1132 Return a reasonable value for use as Origin-State-Id in outgoing
1134 messages.
1135 The value returned is the number of seconds since
1137 19680120T031408Z, the first value that can be encoded as a Diam‐
1138 eter Time(), at the time the diameter application was started.
1139 remove_transport(SvcName, Pred) -> ok | {error, Reason}
1141 Types:
1143 SvcName = service_name()
1145 Pred = Fun | MFA | transport_ref() | list() | true | false
1146 Fun = fun((transport_ref(), connect|listen, list()) -> bool‐
1148 ean())
1149 | fun((transport_ref(), list()) -> boolean())
1150 | fun((list()) -> boolean())
1151 MFA = {atom(), atom(), list()}
1152 Reason = term()
1153 Remove previously added transports.
1155 Pred determines which transports to remove. An arity-3-valued
1157 Pred removes all transports for which Pred(Ref, Type, Opts) re‐
1158 turns true, where Type and Opts are as passed to add_transport/2
1159 and Ref is as returned by it. The remaining forms are equivalent
1160 to an arity-3 fun as follows.
1161 Pred = fun(transport_ref(), list()): fun(Ref, _, Opts) -> Pred(Ref, Opts) end
1163 Pred = fun(list()): fun(_, _, Opts) -> Pred(Opts) end
1164 Pred = transport_ref(): fun(Ref, _, _) -> Pred == Ref end
1165 Pred = list(): fun(_, _, Opts) -> [] == Pred -- Opts end
1166 Pred = true: fun(_, _, _) -> true end
1167 Pred = false: fun(_, _, _) -> false end
1168 Pred = {M,F,A}: fun(Ref, Type, Opts) -> apply(M, F, [Ref, Type, Opts | A]) end
1169 Removing a transport causes the corresponding transport pro‐
1172 cesses to be terminated. Whether or not a DPR message is sent to
1173 a peer is controlled by value of disconnect_cb configured on the
1174 transport.
1175 service_info(SvcName, Info) -> term()
1177 Types:
1179 SvcName = service_name()
1181 Info = Item | [Info]
1182 Item = atom()
1183 Return information about a started service. Requesting info for
1185 an unknown service causes undefined to be returned. Requesting a
1186 list of items causes a tagged list to be returned.
1187 Item can be one of the following.
1189 'Origin-Host':
1191 'Origin-Realm':
1194 'Vendor-Id':
1197 'Product-Name':
1200 'Origin-State-Id':
1203 'Host-IP-Address':
1206 'Supported-Vendor':
1209 'Auth-Application-Id':
1212 'Inband-Security-Id':
1215 'Acct-Application-Id':
1218 'Vendor-Specific-Application-Id':
1221 'Firmware-Revision':
1224 Return a capability value as configured with start_ser‐
1225 vice/2.
1226 applications:
1228 Return the list of applications as configured with
1229 start_service/2.
1230 capabilities:
1232 Return a tagged list of all capabilities values as config‐
1233 ured with start_service/2.
1234 transport:
1236 Return a list containing one entry for each of the service's
1237 transport as configured with add_transport/2. Each entry is
1238 a tagged list containing both configuration and information
1239 about established peer connections. An example return value
1240 with for a client service with Origin-Host "client.exam‐
1241 ple.com" configured with a single transport connected to
1242 "server.example.com" might look as follows.
1243 [[{ref,#Ref<0.0.0.93>},
1245 {type,connect},
1246 {options,[{transport_module,diameter_tcp},
1247 {transport_config,[{ip,{127,0,0,1}},
1248 {raddr,{127,0,0,1}},
1249 {rport,3868},
1250 {reuseaddr,true}]}]},
1251 {watchdog,{<0.66.0>,-576460736368485571,okay}},
1252 {peer,{<0.67.0>,-576460736357885808}},
1253 {apps,[{0,common}]},
1254 {caps,[{origin_host,{"client.example.com","server.example.com"}},
1255 {origin_realm,{"example.com","example.com"}},
1256 {host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
1257 {vendor_id,{0,193}},
1258 {product_name,{"Client","Server"}},
1259 {origin_state_id,{[],[]}},
1260 {supported_vendor_id,{[],[]}},
1261 {auth_application_id,{[0],[0]}},
1262 {inband_security_id,{[],[0]}},
1263 {acct_application_id,{[],[]}},
1264 {vendor_specific_application_id,{[],[]}},
1265 {firmware_revision,{[],[]}},
1266 {avp,{[],[]}}]},
1267 {port,[{owner,<0.69.0>},
1268 {module,diameter_tcp},
1269 {socket,{{127,0,0,1},48758}},
1270 {peer,{{127,0,0,1},3868}},
1271 {statistics,[{recv_oct,656},
1272 {recv_cnt,6},
1273 {recv_max,148},
1274 {recv_avg,109},
1275 {recv_dvi,19},
1276 {send_oct,836},
1277 {send_cnt,6},
1278 {send_max,184},
1279 {send_avg,139},
1280 {send_pend,0}]}]},
1281 {statistics,[{{{0,258,0},recv},3},
1282 {{{0,258,1},send},3},
1283 {{{0,258,0},recv,{'Result-Code',2001}},3},
1284 {{{0,257,0},recv},1},
1285 {{{0,257,1},send},1},
1286 {{{0,257,0},recv,{'Result-Code',2001}},1},
1287 {{{0,280,1},recv},2},
1288 {{{0,280,0},send},2},
1289 {{{0,280,0},send,{'Result-Code',2001}},2}]}]]
1290 Here ref is a transport_ref() and options the corresponding
1293 transport_opt() list passed to add_transport/2. The watchdog
1294 entry shows the state of a connection's RFC 3539 watchdog
1295 state machine. The peer entry identifies the diame‐
1296 ter_app:peer_ref() for which there will have been peer_up/3
1297 callbacks for the Diameter applications identified by the
1298 apps entry, common being the application_alias(). The caps
1299 entry identifies the capabilities sent by the local node and
1300 received from the peer during capabilities exchange. The
1301 port entry displays socket-level information about the
1302 transport connection. The statistics entry presents Diame‐
1303 ter-level counters, an entry like {{{0,280,1},recv},2} say‐
1304 ing that the client has received 2 DWR messages: {0,280,1} =
1305 {Application_Id, Command_Code, R_Flag}.
1306 Note that watchdog, peer, apps, caps and port entries depend
1308 on connectivity with the peer and may not be present. Note
1309 also that the statistics entry presents values accumulated
1310 during the lifetime of the transport configuration.
1311 A listening transport presents its information slightly dif‐
1313 ferently since there may be multiple accepted connections
1314 for the same transport_ref(). The transport info returned by
1315 a server with a single client connection might look as fol‐
1316 lows.
1317 [[{ref,#Ref<0.0.0.61>},
1319 {type,listen},
1320 {options,[{transport_module,diameter_tcp},
1321 {transport_config,[{reuseaddr,true},
1322 {ip,{127,0,0,1}},
1323 {port,3868}]}]},
1324 {accept,[[{watchdog,{<0.56.0>,-576460739249514012,okay}},
1325 {peer,{<0.58.0>,-576460638229179167}},
1326 {apps,[{0,common}]},
1327 {caps,[{origin_host,{"server.example.com","client.example.com"}},
1328 {origin_realm,{"example.com","example.com"}},
1329 {host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
1330 {vendor_id,{193,0}},
1331 {product_name,{"Server","Client"}},
1332 {origin_state_id,{[],[]}},
1333 {supported_vendor_id,{[],[]}},
1334 {auth_application_id,{[0],[0]}},
1335 {inband_security_id,{[],[]}},
1336 {acct_application_id,{[],[]}},
1337 {vendor_specific_application_id,{[],[]}},
1338 {firmware_revision,{[],[]}},
1339 {avp,{[],[]}}]},
1340 {port,[{owner,<0.62.0>},
1341 {module,diameter_tcp},
1342 {socket,{{127,0,0,1},3868}},
1343 {peer,{{127,0,0,1},48758}},
1344 {statistics,[{recv_oct,1576},
1345 {recv_cnt,16},
1346 {recv_max,184},
1347 {recv_avg,98},
1348 {recv_dvi,26},
1349 {send_oct,1396},
1350 {send_cnt,16},
1351 {send_max,148},
1352 {send_avg,87},
1353 {send_pend,0}]}]}],
1354 [{watchdog,{<0.72.0>,-576460638229717546,initial}}]]},
1355 {statistics,[{{{0,280,0},recv},7},
1356 {{{0,280,1},send},7},
1357 {{{0,280,0},recv,{'Result-Code',2001}},7},
1358 {{{0,258,1},recv},3},
1359 {{{0,258,0},send},3},
1360 {{{0,258,0},send,{'Result-Code',2001}},3},
1361 {{{0,280,1},recv},5},
1362 {{{0,280,0},send},5},
1363 {{{0,280,0},send,{'Result-Code',2001}},5},
1364 {{{0,257,1},recv},1},
1365 {{{0,257,0},send},1},
1366 {{{0,257,0},send,{'Result-Code',2001}},1}]}]]
1367 The information presented here is as in the connect case ex‐
1370 cept that the client connections are grouped under an accept
1371 tuple.
1372 Whether or not the transport_opt() pool_size has been con‐
1374 figured affects the format of the listing in the case of a
1375 connecting transport, since a value greater than 1 implies
1376 multiple transport processes for the same transport_ref(),
1377 as in the listening case. The format in this case is similar
1378 to the listening case, with a pool tuple in place of an ac‐
1379 cept tuple.
1380 connections:
1382 Return a list containing one entry for every established
1383 transport connection whose watchdog state machine is not in
1384 the down state. This is a flat view of transport info which
1385 lists only active connections and for which Diameter-level
1386 statistics are accumulated only for the lifetime of the
1387 transport connection. A return value for the server above
1388 might look as follows.
1389 [[{ref,#Ref<0.0.0.61>},
1391 {type,accept},
1392 {options,[{transport_module,diameter_tcp},
1393 {transport_config,[{reuseaddr,true},
1394 {ip,{127,0,0,1}},
1395 {port,3868}]}]},
1396 {watchdog,{<0.56.0>,-576460739249514012,okay}},
1397 {peer,{<0.58.0>,-576460638229179167}},
1398 {apps,[{0,common}]},
1399 {caps,[{origin_host,{"server.example.com","client.example.com"}},
1400 {origin_realm,{"example.com","example.com"}},
1401 {host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
1402 {vendor_id,{193,0}},
1403 {product_name,{"Server","Client"}},
1404 {origin_state_id,{[],[]}},
1405 {supported_vendor_id,{[],[]}},
1406 {auth_application_id,{[0],[0]}},
1407 {inband_security_id,{[],[]}},
1408 {acct_application_id,{[],[]}},
1409 {vendor_specific_application_id,{[],[]}},
1410 {firmware_revision,{[],[]}},
1411 {avp,{[],[]}}]},
1412 {port,[{owner,<0.62.0>},
1413 {module,diameter_tcp},
1414 {socket,{{127,0,0,1},3868}},
1415 {peer,{{127,0,0,1},48758}},
1416 {statistics,[{recv_oct,10124},
1417 {recv_cnt,132},
1418 {recv_max,184},
1419 {recv_avg,76},
1420 {recv_dvi,9},
1421 {send_oct,10016},
1422 {send_cnt,132},
1423 {send_max,148},
1424 {send_avg,75},
1425 {send_pend,0}]}]},
1426 {statistics,[{{{0,280,0},recv},62},
1427 {{{0,280,1},send},62},
1428 {{{0,280,0},recv,{'Result-Code',2001}},62},
1429 {{{0,258,1},recv},3},
1430 {{{0,258,0},send},3},
1431 {{{0,258,0},send,{'Result-Code',2001}},3},
1432 {{{0,280,1},recv},66},
1433 {{{0,280,0},send},66},
1434 {{{0,280,0},send,{'Result-Code',2001}},66},
1435 {{{0,257,1},recv},1},
1436 {{{0,257,0},send},1},
1437 {{{0,257,0},send,{'Result-Code',2001}},1}]}]]
1438 Note that there may be multiple entries with the same ref,
1441 in contrast to transport info.
1442 statistics:
1444 Return a {{Counter, Ref}, non_neg_integer()} list of counter
1445 values. Ref can be either a transport_ref() or a diame‐
1446 ter_app:peer_ref(). Entries for the latter are folded into
1447 corresponding entries for the former as peer connections go
1448 down. Entries for both are removed at remove_transport/2.
1449 The Diameter-level statistics returned by transport and con‐
1450 nections info are based upon these entries.
1451 diameter_app:peer_ref():
1453 Return transport configuration associated with a single
1454 peer, as passed to add_transport/2. The returned list is
1455 empty if the peer is unknown. Otherwise it contains the ref,
1456 type and options tuples as in transport and connections info
1457 above. For example:
1458 [{ref,#Ref<0.0.0.61>},
1460 {type,accept},
1461 {options,[{transport_module,diameter_tcp},
1462 {transport_config,[{reuseaddr,true},
1463 {ip,{127,0,0,1}},
1464 {port,3868}]}]}]
1465 services() -> [SvcName]
1468 Types:
1470 SvcName = service_name()
1472 Return the list of started services.
1474 session_id(Ident) -> OctetString()
1476 Types:
1478 Ident = DiameterIdentity()
1480 Return a value for a Session-Id AVP.
1482 The value has the form required by section 8.8 of RFC 6733.
1484 Ident should be the Origin-Host of the peer from which the mes‐
1485 sage containing the returned value will be sent.
1486 start() -> ok | {error, Reason}
1488 Start the diameter application.
1490 The diameter application must be started before starting a ser‐
1492 vice. In a production system this is typically accomplished by a
1493 boot file, not by calling start/0 explicitly.
1494 start_service(SvcName, Options) -> ok | {error, Reason}
1496 Types:
1498 SvcName = service_name()
1500 Options = [service_opt()]
1501 Reason = term()
1502 Start a diameter service.
1504 A service defines a locally-implemented Diameter node, specify‐
1506 ing the capabilities to be advertised during capabilities ex‐
1507 change. Transports are added to a service using add_transport/2.
1508 Note:
1510 A transport can both override its service's capabilities and re‐
1511 strict its supported Diameter applications so "service = Diame‐
1512 ter node as identified by Origin-Host" is not necessarily the
1513 case.
1514 stop() -> ok | {error, Reason}
1517 Stop the diameter application.
1519 stop_service(SvcName) -> ok | {error, Reason}
1521 Types:
1523 SvcName = service_name()
1525 Reason = term()
1526 Stop a diameter service.
1528 Stopping a service causes all associated transport connections
1530 to be broken. A DPR message will be sent as in the case of re‐
1531 move_transport/2.
1532 Note:
1534 Stopping a service does not remove any associated transports:
1535 remove_transport/2 must be called to remove transport configura‐
1536 tion.
1537 subscribe(SvcName) -> true
1540 Types:
1542 SvcName = service_name()
1544 Subscribe to service_event() messages from a service.
1546 It is not an error to subscribe to events from a service that
1548 does not yet exist. Doing so before adding transports is re‐
1549 quired to guarantee the reception of all transport-related
1550 events.
1551 unsubscribe(SvcName) -> true
1553 Types:
1555 SvcName = service_name()
1557 Unsubscribe to event messages from a service.
1559
1561 diameter_app(3), diameter_transport(3), diameter_dict(4)
1562Ericsson AB diameter 2.2.4 diameter(3)