diff options
Diffstat (limited to 'lib/diameter/doc/src/diameter.xml')
| -rw-r--r-- | lib/diameter/doc/src/diameter.xml | 255 |
1 files changed, 189 insertions, 66 deletions
diff --git a/lib/diameter/doc/src/diameter.xml b/lib/diameter/doc/src/diameter.xml index 2cbe48ecce..6b84b22eb5 100644 --- a/lib/diameter/doc/src/diameter.xml +++ b/lib/diameter/doc/src/diameter.xml @@ -397,10 +397,10 @@ from the peer offers it.</p> Note that each tuple communicates one or more AVP values. It is an error to specify duplicate tuples.</p> -<marker id="evaluable"/> +<marker id="eval"/> </item> -<tag><c>evaluable() = {M,F,A} | fun() | [evaluable() | A]</c></tag> +<tag><c>eval() = {M,F,A} | fun() | [eval() | A]</c></tag> <item> <p> An expression that can be evaluated as a function in the following @@ -418,7 +418,7 @@ eval(F) -> </pre> <p> -Applying an <c>&evaluable;</c> +Applying an <c>&eval;</c> <c>E</c> to an argument list <c>A</c> is meant in the sense of <c>eval([E|A])</c>.</p> @@ -484,11 +484,11 @@ Matches only those peers whose Origin-Realm has the specified value, or all peers if the atom <c>any</c>.</p> </item> -<tag><c>{eval, &evaluable;}</c></tag> +<tag><c>{eval, &eval;}</c></tag> <item> <p> Matches only those peers for which the specified -<c>&evaluable;</c> returns +<c>&eval;</c> returns <c>true</c> when applied to the connection's <c>diameter_caps</c> record. Any other return value or exception is equivalent to <c>false</c>.</p> @@ -650,7 +650,7 @@ Result = ResultCode | {capabilities_cb, CB, ResultCode|discard} Caps = #diameter_caps{} Pkt = #diameter_packet{} ResultCode = integer() -CB = &evaluable; +CB = &eval; </pre> <p> @@ -798,15 +798,31 @@ be matched by corresponding &capability; configuration, of </item> <tag> -<marker id="incoming_maxlen"/><c>{incoming_maxlen, 0..16777215}</c></tag> +<marker id="decode_format"/> +<c>{decode_format, record | list | map | none}</c></tag> <item> <p> -Bound on the expected size of incoming Diameter messages. -Messages larger than the specified number of bytes are discarded.</p> +The format of decoded messages and grouped AVPs in the <c>msg</c> field +of diameter_packet records and <c>value</c> field of diameter_avp +records respectively. +If <c>record</c> then a record whose definition is generated from the +dictionary file in question. +If <c>list</c> or <c>map</c> then a <c>[Name | Avps]</c> pair where +<c>Avps</c> is a list of AVP name/values pairs or a map keyed on +AVP names respectively. +If <c>none</c> then the atom-value message name, or <c>undefined</c> +for a Grouped AVP. +See also &codec_message;.</p> <p> -Defaults to <c>16777215</c>, the maximum value of the 24-bit Message -Length field in a Diameter Header.</p> +Defaults to <c>record</c>.</p> + +<note> +<p> +AVPs are decoded into a list of diameter_avp records in <c>avps</c> +field of diameter_packet records independently of +<c>decode_format</c>.</p> +</note> </item> @@ -814,7 +830,7 @@ Length field in a Diameter Header.</p> | node | nodes | [node()] - | evaluable()}</c></tag> + | eval()}</c></tag> <item> <p> The degree to which the service allows multiple transport @@ -825,7 +841,7 @@ at capabilities exchange.</p> If <c>[node()]</c> then a connection is rejected if another already exists on any of the specified nodes. Types <c>false</c>, <c>node</c>, <c>nodes</c> and -&evaluable; are equivalent to +&eval; are equivalent to <c>[]</c>, <c>[node()]</c>, <c>[node()|nodes()]</c> and the evaluated value respectively, evaluation of each expression taking place whenever a new connection is to be established. @@ -840,7 +856,7 @@ by their own peer and watchdog state machines.</p> Defaults to <c>nodes</c>.</p> </item> -<tag><c>{sequence, {H,N} | &evaluable;}</c></tag> +<tag><c>{sequence, {H,N} | &eval;}</c></tag> <item> <p> A constant value <c>H</c> for the topmost <c>32-N</c> bits of @@ -875,7 +891,7 @@ outgoing requests.</p> </warning> </item> -<tag><c>{share_peers, boolean() | [node()] | evaluable()}</c></tag> +<tag><c>{share_peers, boolean() | [node()] | eval()}</c></tag> <item> <p> Nodes to which peer connections established on the local @@ -888,7 +904,7 @@ configured to use them: see <c>use_shared_peers</c> below.</p> If <c>false</c> then peers are not shared. If <c>[node()]</c> then peers are shared with the specified list of nodes. -If <c>evaluable()</c> then peers are shared with the nodes returned +If <c>eval()</c> then peers are shared with the nodes returned by the specified function, evaluated whenever a peer connection becomes available or a remote service requests information about local connections. @@ -914,59 +930,36 @@ of a single Diameter node across multiple Erlang nodes.</p> </note> </item> -<tag><c>{spawn_opt, [term()]}</c></tag> -<item> -<p> -Options list passed to &spawn_opt; when spawning a process for an -incoming Diameter request, unless the transport in question -specifies another value. -Options <c>monitor</c> and <c>link</c> are ignored.</p> - -<p> -Defaults to the empty list.</p> -</item> - <tag> -<marker id="strict_mbit"/><c>{strict_mbit, boolean()}</c></tag> +<marker id="strict_arities"/><c>{strict_arities, boolean() + | encode + | decode}</c></tag> <item> <p> -Whether or not to regard an AVP setting the M-bit as erroneous when -the command grammar in question does not explicitly allow the AVP. -If <c>true</c> then such AVPs are regarded as 5001 errors, -DIAMETER_AVP_UNSUPPORTED. -If <c>false</c> then the M-bit is ignored and policing -it becomes the receiver's responsibility.</p> +Whether or not to require that the number of AVPs in a message or +grouped AVP agree with those specified in the dictionary in question +when passing messages to &man_app; callbacks. +If <c>true</c> then mismatches in an outgoing messages cause message +encoding to fail, while mismatches in an incoming message are reported +as 5005/5009 errors in the errors field of the diameter_packet record +passed to &app_handle_request; or &app_handle_answer; callbacks. +If <c>false</c> then neither error is enforced/detected. +If <c>encode</c> or <c>decode</c> then errors are only +enforced/detected on outgoing or incoming messages respectively.</p> <p> Defaults to <c>true</c>.</p> -<warning> -<p> -RFC 6733 is unclear about the semantics of the M-bit. -One the one hand, the CCF specification in section 3.2 documents AVP -in a command grammar as meaning <em>any</em> arbitrary AVP; on the -other hand, 1.3.4 states that AVPs setting the M-bit cannot be added -to an existing command: the modified command must instead be -placed in a new Diameter application.</p> -<p> -The reason for the latter is presumably interoperability: -allowing arbitrary AVPs setting the M-bit in a command makes its -interpretation implementation-dependent, since there's no -guarantee that all implementations will understand the same set of -arbitrary AVPs in the context of a given command. -However, interpreting <c>AVP</c> in a command grammar as any -AVP, regardless of M-bit, renders 1.3.4 meaningless, since the receiver -can simply ignore any AVP it thinks isn't relevant, regardless of the -sender's intent.</p> +<note> <p> -Beware of confusing mandatory in the sense of the M-bit with mandatory -in the sense of the command grammar. -The former is a semantic requirement: that the receiver understand the -semantics of the AVP in the context in question. -The latter is a syntactic requirement: whether or not the AVP must -occur in the message in question.</p> -</warning> - +Disabling arity checks affects the form of messages at encode/decode. +In particular, decoded AVPs are represented as lists of values, +regardless of the AVP's arity (ie. expected number in the message/AVP +grammar in question), and values are expected to be supplied as lists +at encode. +This differs from the historic decode behaviour of representing AVPs +of arity 1 as bare values, not wrapped in a list.</p> +</note> </item> <tag> @@ -993,7 +986,27 @@ The default value is for backwards compatibility.</p> </item> -<tag><c>{use_shared_peers, boolean() | [node()] | evaluable()}</c></tag> +<tag> +<marker id="traffic_counters"/><c>{traffic_counters, boolean()}</c></tag> +<item> +<p> +Whether or not to count application-specific messages; those for which +&man_app; callbacks take place. +If false then only messages handled by diameter itself are counted: +CER/CEA, DWR/DWA, DPR/DPA.</p> + +<p> +Defaults to <c>true</c>.</p> + +<note> +<p> +Disabling counters is a performance improvement, but means that the +omitted counters are not returned by &service_info;.</p> +</note> + +</item> + +<tag><c>{use_shared_peers, boolean() | [node()] | eval()}</c></tag> <item> <p> Nodes from which communicated peers are made available in @@ -1003,7 +1016,7 @@ the remote candidates list of &app_pick_peer; callbacks.</p> If <c>false</c> then remote peers are not used. If <c>[node()]</c> then only peers from the specified list of nodes are used. -If <c>evaluable()</c> then only peers returned by the specified +If <c>eval()</c> then only peers returned by the specified function are used, evaluated whenever a remote service communicates information about an available peer connection. The value <c>true</c> is equivalent to <c>fun &nodes;</c>. @@ -1028,6 +1041,15 @@ each node from which requests are sent.</p> </warning> </item> +<tag><c>&transport_opt;</c></tag> +<item> +<p> +Any transport option except <c>applications</c> or +<c>capabilities</c>. +Used as defaults for transport configuration, values passed to +&add_transport; overriding values configured on the service.</p> +</item> + </taglist> <marker id="transport_opt"/> @@ -1061,6 +1083,37 @@ implies having to set matching *-Application-Id AVPs in a </item> <tag> +<marker id="avp_dictionaries"/><c>{avp_dictionaries, [module()]}</c></tag> +<item> +<p> +A list of alternate dictionary modules with which to encode/decode +AVPs that are not defined by the dictionary of the application in +question. +At decode, such AVPs are represented as diameter_avp records in the +<c>'AVP'</c> field of a decoded message or Grouped AVP, the first +alternate that succeeds in decoding the AVP setting the record's value +field. +At encode, values in an <c>'AVP'</c> list can be passed as AVP +name/value 2-tuples, and it is an encode error for no alternate to +define the AVP of such a tuple.</p> + +<p> +Defaults to the empty list.</p> + +<note> +<p> +The motivation for alternate dictionaries is RFC 7683, Diameter +Overload Indication Conveyance (DOIC), which defines AVPs to +be piggybacked onto existing application messages rather than defining +an application of its own. +The DOIC dictionary is provided by the diameter application, as module +<c>diameter_gen_doic_rfc7683</c>, but alternate dictionaries can be +used to encode/decode any set of AVPs not known to an application +dictionary.</p> +</note> +</item> + +<tag> <marker id="capabilities"/><c>{capabilities, [&capability;]}</c></tag> <item> <p> @@ -1075,7 +1128,7 @@ TLS is desired over TCP as implemented by &man_tcp;.</p> </item> <tag> -<marker id="capabilities_cb"/><c>{capabilities_cb, &evaluable;}</c></tag> +<marker id="capabilities_cb"/><c>{capabilities_cb, &eval;}</c></tag> <item> <p> Callback invoked upon reception of CER/CEA during capabilities @@ -1169,7 +1222,7 @@ transport.</p> </item> <tag> -<marker id="disconnect_cb"/><c>{disconnect_cb, &evaluable;}</c></tag> +<marker id="disconnect_cb"/><c>{disconnect_cb, &eval;}</c></tag> <item> <p> Callback invoked prior to terminating the transport process of a @@ -1269,6 +1322,19 @@ Defaults to 5000.</p> </item> <tag> +<marker id="incoming_maxlen"/><c>{incoming_maxlen, 0..16777215}</c></tag> +<item> +<p> +Bound on the expected size of incoming Diameter messages. +Messages larger than the specified number of bytes are discarded.</p> + +<p> +Defaults to <c>16777215</c>, the maximum value of the 24-bit Message +Length field in a Diameter Header.</p> + +</item> + +<tag> <marker id="length_errors"/><c>{length_errors, exit|handle|discard}</c></tag> <item> <p> @@ -1326,7 +1392,64 @@ incoming Diameter request. Options <c>monitor</c> and <c>link</c> are ignored.</p> <p> -Defaults to the list configured on the service if not specified.</p> +Defaults to the empty list.</p> +</item> + +<tag> +<marker id="strict_capx"/><c>{strict_capx, boolean()]}</c></tag> +<item> +<p> +Whether or not to enforce the RFC 6733 requirement that any message +before capabilities exchange should close the peer connection. +If false then unexpected messages are discarded.</p> + +<p> +Defaults to true. +Changing this results in non-standard behaviour, but can be useful in +case peers are known to be behave badly.</p> +</item> + +<tag> +<marker id="strict_mbit"/><c>{strict_mbit, boolean()}</c></tag> +<item> +<p> +Whether or not to regard an AVP setting the M-bit as erroneous when +the command grammar in question does not explicitly allow the AVP. +If <c>true</c> then such AVPs are regarded as 5001 errors, +DIAMETER_AVP_UNSUPPORTED. +If <c>false</c> then the M-bit is ignored and policing +it becomes the receiver's responsibility.</p> + +<p> +Defaults to <c>true</c>.</p> + +<warning> +<p> +RFC 6733 is unclear about the semantics of the M-bit. +One the one hand, the CCF specification in section 3.2 documents AVP +in a command grammar as meaning <em>any</em> arbitrary AVP; on the +other hand, 1.3.4 states that AVPs setting the M-bit cannot be added +to an existing command: the modified command must instead be +placed in a new Diameter application.</p> +<p> +The reason for the latter is presumably interoperability: +allowing arbitrary AVPs setting the M-bit in a command makes its +interpretation implementation-dependent, since there's no +guarantee that all implementations will understand the same set of +arbitrary AVPs in the context of a given command. +However, interpreting <c>AVP</c> in a command grammar as any +AVP, regardless of M-bit, renders 1.3.4 meaningless, since the receiver +can simply ignore any AVP it thinks isn't relevant, regardless of the +sender's intent.</p> +<p> +Beware of confusing mandatory in the sense of the M-bit with mandatory +in the sense of the command grammar. +The former is a semantic requirement: that the receiver understand the +semantics of the AVP in the context in question. +The latter is a syntactic requirement: whether or not the AVP must +occur in the message in question.</p> +</warning> + </item> <tag> |