• discovery purposes only.
• negotiation but only as an initiator (client).
• negotiation but only as a responder.
• negotiation as an initiator or responder.
• synchronization but only as an initiator (recipient).
• synchronization but only as a responder and/or flooder.
• synchronization as an initiator, responder, and/or flooder.

• Authorization of ASAs is not defined as part of GRASP and is a subject for future study.
• User-supplied explicit locators for an objective are not supported. The GRASP core will supply the locator, using the IP address of the node concerned.
• The rapid mode of GRASP (Section 2.5.4 of RFC 8990) is not supported.

1. In multithreading, the operating system and language will provide the necessary support for asynchronous operations, including creation of new threads, context switching between threads, queues, locks, and implicit wait states. In this case, API calls can be treated as simple synchronous function calls within their own thread, even if the function includes wait states, blocking, and queueing. Concurrent operations will each run in their own threads. For example, the discover() call may not return until discovery results have arrived or a timeout has occurred. If the ASA has other work to do, the discover() call must be in a thread of its own.
2. In an event loop implementation with polling, blocking calls are not acceptable. Therefore, all calls must be non-blocking, and the main loop could support multiple GRASP sessions in parallel by repeatedly polling each one for a change of state. To facilitate this, the API implementation would provide non-blocking versions of all the functions that otherwise involve blocking and queueing. In these calls, a 'noReply' code will be returned by each call instead of blocking, until such time as the event for which it is waiting (or a failure) has occurred. Thus, for example, discover() would return 'noReply' instead of waiting until discovery has succeeded or timed out. The discover() call would be repeated in every cycle of the main loop until it completes. Effectively, it becomes a polling call.
3. It was noted earlier that some GRASP messages are not idempotent; in particular, this applies to each step in a negotiation session -- sending the same message twice might produce unintended side effects. This is not affected by event loop polling: repeating a call after a 'noReply' does not repeat a message; it simply checks whether a reply has been received.
4. In an event loop implementation with callbacks, the ASA programmer would provide a callback function for each asynchronous operation. This would be called asynchronously when a reply is received or a failure such as a timeout occurs.

Registration:

These functions allow an ASA to register itself with the GRASP core and allow a registered ASA to register the GRASP objectives that it will manipulate.

Discovery:

This function allows an ASA that needs to initiate negotiation or synchronization of a particular objective to discover a peer willing to respond.

Negotiation:

These functions allow an ASA to act as an initiator (requester) or responder (listener) for a GRASP negotiation session. After initiation, negotiation is a symmetric process, so most of the functions can be used by either party.

Synchronization:

These functions allow an ASA to act as an initiator (requester) or responder (listener and data source) for a GRASP synchronization session.

Flooding:

These functions allow an ASA to send and receive an objective that is flooded to all nodes of the ACP.

1 - Declined:

used to indicate that the other end has sent a GRASP Negotiation End message (M_END) with a Decline option (O_DECLINE).

2 - No reply:

used in non-blocking calls to indicate that the other end has sent no reply so far (see Section 2.2).

3 - Unspecified error:

used when no more specific error codes apply.

name (UTF-8 string):

The objective's name

neg (Boolean flag):

True if objective supports negotiation (default False)

synch (Boolean flag):

True if objective supports synchronization (default False)

dry (Boolean flag):

True if objective supports dry-run negotiation (default False)

Note 1:

Only one of 'synch' or 'neg' may be True.

Note 2:

'dry' must not be True unless 'neg' is also True.

Note 3:

In some programming languages, the preferred implementation may be to represent the Boolean flags as bits in a single byte, which is how they are encoded in GRASP messages. In other languages, an enumeration might be preferable.

loop_count (unsigned integer, uint8_t):

Limit on negotiation steps, etc. (default GRASP_DEF_LOOPCT; see [RFC 8990]). The 'loop_count' is set to a suitable value by the initiator of a negotiation, to prevent indefinite loops. It is also used to limit the propagation of discovery and flood messages.

value:

A specific data structure expressing the value of the objective. The format is language dependent, with the constraint that it can be validly represented in CBOR [RFC 8949].

• An important advantage of CBOR is that the value of an objective can be completely opaque to the GRASP core yet pass transparently through it to and from the ASA. Although the GRASP core must validate the format and syntax of GRASP messages, it cannot validate the value of an objective; all it can do is detect malformed CBOR. The handling of decoding errors depends on the CBOR library in use, but a corresponding error code ('CBORfail') is defined in the API and will be returned to the ASA if a faulty message can be assigned to a current GRASP session. However, it is the responsibility of each ASA to validate the value of a received objective, as discussed in Section 5.3 of RFC 8949. If the programming language in use is suitably object-oriented, the GRASP API may deserialize the value and present it to the ASA as an object. If not, it will be presented as a CBOR data item. In all cases, the syntax and semantics of the objective value are the responsibility of the ASA.
• A requirement for all language mappings and all API implementations is that, regardless of what other options exist for a language-specific representation of the value, there is always an option to use a raw CBOR data item as the value. The API will then wrap this with CBOR Tag 24 as an encoded CBOR data item for transmission via GRASP, and unwrap it after reception. By this means, ASAs will be able to communicate regardless of programming language.

 typedef struct {
    unsigned char *name;
    uint8_t flags;            // flag bits as defined by GRASP
    uint8_t loop_count;
    uint32_t value_size;      // size of value in bytes
    cbor_mutable_data cbor_value;
                             // CBOR bytestring (libcbor/cbor/data.h)
                 } objective;

 class objective:
    """A GRASP objective"""
    def __init__(self, name):
        self.name = name        #Unique name (string)
        self.negotiate = False  #True if negotiation supported
        self.dryrun = False     #True if dry-run supported
        self.synch = False      #True if synchronization supported
        self.loop_count = GRASP_DEF_LOOPCT  # Default starting value
        self.value = None       #Place holder; any Python object

locator:

The actual locator, either an IP address or an ASCII string.

ifi (unsigned integer):

The interface identifier index via which this was discovered (of limited use to most ASAs).

expire (system dependent type):

The time on the local system clock when this locator will expire from the cache.

The following covers all locator types currently supported by GRASP:

• is_ipaddress (Boolean) - True if the locator is an IP address.
• is_fqdn (Boolean) - True if the locator is a Fully Qualified Domain Name (FQDN).
• is_uri (Boolean) - True if the locator is a URI.

These options are mutually exclusive. Depending on the programming language, they could be represented as a bit pattern or an enumeration.

diverted (Boolean):

True if the locator was discovered via a Divert option.

protocol (unsigned integer):

Applicable transport protocol (IPPROTO_TCP or IPPROTO_UDP). These constants are defined in the CDDL specification of GRASP [RFC 8990].

port (unsigned integer):

Applicable port number.

objective:

An objective.

locator:

The asa_locator associated with the objective, or a null value.

• discover() whose callback would be discovery_received().
• request_negotiate() whose callback would be negotiate_step_received().
• negotiate_step() whose callback would be negotiate_step_received().
• listen_negotiate() whose callback would be negotiate_step_received().
• synchronize() whose callback would be synchronization_received().

• register_asa() All ASAs must use this call before issuing any other API calls.
  • Input parameter:
    • name of the ASA (UTF-8 string)
  • Return value:
    • errorcode (unsigned integer)
    • asa_handle (unsigned integer)
  • This initializes the state in the GRASP module for the calling entity (the ASA). In the case of success, an 'asa_handle' is returned, which the ASA must present in all subsequent calls. In the case of failure, the ASA has not been authorized and cannot operate. The 'asa_handle' value is undefined.
• deregister_asa()
  • Input parameters:
    • asa_handle (unsigned integer)
    • name of the ASA (UTF-8 string)
  • Return value:
    • errorcode (unsigned integer)
  • This removes all state in the GRASP module for the calling entity (the ASA) and deregisters any objectives it has registered. Note that these actions must also happen automatically if an ASA exits.
  • Note -- the ASA name is, strictly speaking, redundant in this call but is present to detect and reject erroneous deregistrations.
• register_objective() ASAs must use this call for any objective whose value they need to transmit by negotiation, synchronization, or flooding.
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
    • ttl (unsigned integer -- default GRASP_DEF_TIMEOUT)
    • discoverable (Boolean -- default False)
    • overlap (Boolean -- default False)
    • local (Boolean -- default False)
  • Return value:
    • errorcode (unsigned integer)
  • This registers an objective that this ASA may modify and transmit to other ASAs by flooding or negotiation. It is not necessary to register an objective that is only received by GRASP synchronization or flooding. The 'objective' becomes a candidate for discovery. However, discovery responses should not be enabled until the ASA calls listen_negotiate() or listen_synchronize(), showing that it is able to act as a responder. The ASA may negotiate the objective or send synchronization or flood data. Registration is not needed for "read-only" operations, i.e., the ASA only wants to receive synchronization or flooded data for the objective concerned.
  • The 'ttl' parameter is the valid lifetime (time to live) in milliseconds of any discovery response generated for this objective. The default value should be the GRASP default timeout (GRASP_DEF_TIMEOUT; see [RFC 8990]).
  • If the parameter 'discoverable' is True, the objective is immediately discoverable. This is intended for objectives that are only defined for GRASP discovery and that do not support negotiation or synchronization.
  • If the parameter 'overlap' is True, more than one ASA may register this objective in the same GRASP instance. This is of value for life cycle management of ASAs [ASA-GUIDE] and must be used consistently for a given objective (always True or always False).
  • If the parameter 'local' is True, discovery must return a link-local address. This feature is for objectives that must be restricted to the local link.
  • This call may be repeated for multiple objectives.
• deregister_objective()
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
  • Return value:
    • errorcode (unsigned integer)
  • The 'objective' must have been registered by the calling ASA; if not, this call fails. Otherwise, it removes all state in the GRASP module for the given objective.

• discover() This function may be used by any ASA to discover peers handling a given objective.
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
    • timeout (unsigned integer)
    • minimum_TTL (unsigned integer)
  • Return values:
    • errorcode (unsigned integer)
    • locator_list (structure)
  • This returns a list of discovered 'asa_locators' for the given objective. An empty list means that no locators were discovered within the timeout. Note that this structure includes all the fields described in Section 2.3.2.5.
  • The parameter 'minimum_TTL' must be greater than or equal to zero. Any locally cached locators for the objective whose remaining time to live in milliseconds is less than or equal to 'minimum_TTL' are deleted first. Thus, 'minimum_TTL' = 0 will flush all entries. Note that this will not affect sessions already in progress using the deleted locators.
  • If the parameter 'timeout' is zero, any remaining locally cached locators for the objective are returned immediately, and no other action is taken. (Thus, a call with 'minimum_TTL' and 'timeout' both equal to zero is pointless.)
  • If the parameter 'timeout' is greater than zero, GRASP discovery is performed, and all results obtained before the timeout in milliseconds expires are returned. If no results are obtained, an empty list is returned after the timeout. That is not an error condition. GRASP discovery is not a deterministic process. If there are multiple nodes handling an objective, none, some, or all of them will be discovered before the timeout expires.
  • Asynchronous Mechanisms:

    Threaded implementation:

    This should be called in a separate thread if asynchronous operation is required.

    Event loop implementation:

    An additional in/out 'session_handle' parameter is used. If the 'errorcode' parameter has the value 2 ('noReply'), no response has been received so far. The 'session_handle' parameter must be presented in subsequent calls. A callback may be used in the case of a non-zero timeout.

Initiator                         Responder
---------                         ---------

                                  listen_negotiate() \ Await request
                         
request_negotiate()
          M_REQ_NEG      ->       negotiate_step()   \ Open session,
                         <-      M_NEGOTIATE         / start negotiation
negotiate_step()
        M_NEGOTIATE      ->       negotiate_step()   \ Continue
                         <-      M_NEGOTIATE         / negotiation
                         ...
negotiate_wait()                                     \ Insert
        M_WAIT           ->                          / delay
negotiate_step()
        M_NEGOTIATE      ->       negotiate_step()   \ Continue
                         <-      M_NEGOTIATE         / negotiation
negotiate_step()
        M_NEGOTIATE      ->       end_negotiate()    \ End
                         <-      M_END               / negotiation

                                                     \ Process results 

• request_negotiate() This function is used by any ASA to initiate negotiation of a GRASP objective as a requester (client).
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
    • peer (asa_locator)
    • timeout (unsigned integer)
  • Return values:
    • errorcode (unsigned integer)
    • session_handle (structure) (undefined unless successful)
    • proffered_objective (structure) (undefined unless successful)
    • reason (string) (empty unless negotiation declined)
  • This function opens a negotiation session between two ASAs. Note that GRASP currently does not support multiparty negotiation, which would need to be added as an extended function.
  • The 'objective' parameter must include the requested value, and its loop count should be set to a suitable starting value by the ASA. If not, the GRASP default will apply.
  • Note that a given negotiation session may or may not be a dry-run negotiation; the two modes must not be mixed in a single session.
  • The 'peer' parameter is the target node; it must be an 'asa_locator' as returned by discover(). If 'peer' is null, GRASP discovery is automatically performed first to find a suitable peer (i.e., any node that supports the objective in question).
  • The 'timeout' parameter is described in Section 2.3.2.3.
  • If the 'errorcode' return value is 0, the negotiation has successfully started. There are then two cases:
    1. The 'session_handle' parameter is null. In this case, the negotiation has succeeded with one exchange of messages, and the peer has accepted the request. The returned 'proffered_objective' contains the value accepted by the peer, which is therefore equal to the value in the requested 'objective'. For this reason, no session handle is needed, since the session has ended.
    2. The 'session_handle' parameter is not null. In this case, negotiation must continue. The 'session_handle' must be presented in all subsequent negotiation steps. The returned 'proffered_objective' contains the first value proffered by the negotiation peer in the first exchange of messages; in other words, it is a counter-offer. The contents of this instance of the objective must be used to prepare the next negotiation step (see negotiate_step() below) because it contains the updated loop count, sent by the negotiation peer. The GRASP code automatically decrements the loop count by 1 at each step and returns an error if it becomes zero. Since this terminates the negotiation, the other end will experience a timeout, which will terminate the other end of the session. This function must be followed by calls to 'negotiate_step' and/or 'negotiate_wait' and/or 'end_negotiate' until the negotiation ends. 'request_negotiate' may then be called again to start a new negotiation.
  • If the 'errorcode' parameter has the value 1 ('declined'), the negotiation has been declined by the peer (M_END and O_DECLINE features of GRASP). The 'reason' string is then available for information and diagnostic use, but it may be a null string. For this and any other error code, an exponential backoff is recommended before any retry (see Section 3).
  • Asynchronous Mechanisms:

    Threaded implementation:

    This should be called in a separate thread if asynchronous operation is required.

    Event loop implementation:

    The 'session_handle' parameter is used to distinguish multiple simultaneous sessions. If the 'errorcode' parameter has the value 2 ('noReply'), no response has been received so far. The 'session_handle' parameter must be presented in subsequent calls.
  • Use of dry-run mode must be consistent within a GRASP session. The state of the 'dry' flag in the initial request_negotiate() call must be the same in all subsequent negotiation steps of the same session. The semantics of the dry-run mode are built into the ASA; GRASP merely carries the flag bit.
  • Special note for the ACP infrastructure ASA: It is likely that this ASA will need to discover and negotiate with its peers in each of its on-link neighbors. It will therefore need to know not only the link-local IP address but also the physical interface and transport port for connecting to each neighbor. One implementation approach to this is to include these details in the 'session_handle' data structure, which is opaque to normal ASAs.
• listen_negotiate() This function is used by an ASA to start acting as a negotiation responder (listener) for a given GRASP objective.
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
  • Return values:
    • errorcode (unsigned integer)
    • session_handle (structure) (undefined unless successful)
    • requested_objective (structure) (undefined unless successful)
  • This function instructs GRASP to listen for negotiation requests for the given 'objective'. It also enables discovery responses for the objective, as mentioned under register_objective() in Section 2.3.3.
  • Asynchronous Mechanisms:

    Threaded implementation:

    It will block waiting for an incoming request, so it should be called in a separate thread if asynchronous operation is required. Unless there is an unexpected failure, this call only returns after an incoming negotiation request. If the ASA supports multiple simultaneous transactions, a new sub-thread must be spawned for each new session, so that listen_negotiate() can be called again immediately.

    Event loop implementation:

    A 'session_handle' parameter is used to distinguish individual sessions. If the ASA supports multiple simultaneous transactions, a new event must be inserted in the event loop for each new session, so that listen_negotiate() can be reactivated immediately.
  • This call only returns (threaded model) or triggers (event loop) after an incoming negotiation request. When this occurs, 'requested_objective' contains the first value requested by the negotiation peer. The contents of this instance of the objective must be used in the subsequent negotiation call because it contains the loop count sent by the negotiation peer. The 'session_handle' must be presented in all subsequent negotiation steps.
  • This function must be followed by calls to 'negotiate_step' and/or 'negotiate_wait' and/or 'end_negotiate' until the negotiation ends.
  • If an ASA is capable of handling multiple negotiations simultaneously, it may call 'listen_negotiate' simultaneously from multiple threads, or insert multiple events. The API and GRASP implementation must support re-entrant use of the listening state and the negotiation calls. Simultaneous sessions will be distinguished by the threads or events themselves, the GRASP session handles, and the underlying unicast transport sockets.
• stop_listen_negotiate() This function is used by an ASA to stop acting as a responder (listener) for a given GRASP objective.
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
  • Return value:
    • errorcode (unsigned integer)
  • Instructs GRASP to stop listening for negotiation requests for the given objective, i.e., cancels 'listen_negotiate'.
  • Asynchronous Mechanisms:

    Threaded implementation:

    Must be called from a different thread than 'listen_negotiate'.

    Event loop implementation:

    No special considerations.
• negotiate_step() This function is used by either ASA in a negotiation session to make the next step in negotiation.
  • Input parameters:
    • asa_handle (unsigned integer)
    • session_handle (structure)
    • objective (structure)
    • timeout (unsigned integer) as described in Section 2.3.2.3
  • Return values:
    • Exactly as for 'request_negotiate'
  • Executes the next negotiation step with the peer. The 'objective' parameter contains the next value being proffered by the ASA in this step. It must also contain the latest 'loop_count' value received from request_negotiate() or negotiate_step().
  • Asynchronous Mechanisms:

    Threaded implementation:

    Usually called in the same thread as the preceding 'request_negotiate' or 'listen_negotiate', with the same value of 'session_handle'.

    Event loop implementation:

    Must use the same value of 'session_handle' returned by the preceding 'request_negotiate' or 'listen_negotiate'.
• negotiate_wait() This function is used by either ASA in a negotiation session to delay the next step in negotiation.
  • Input parameters:
    • asa_handle (unsigned integer)
    • session_handle (structure)
    • timeout (unsigned integer)
  • Return value:
    • errorcode (unsigned integer)
  • Requests the remote peer to delay the negotiation session by 'timeout' milliseconds, thereby extending the original timeout. This function simply triggers a GRASP Confirm Waiting message (see [RFC 8990] for details).
  • Asynchronous Mechanisms:

    Threaded implementation:

    Called in the same thread as the preceding 'request_negotiate' or 'listen_negotiate', with the same value of 'session_handle'.

    Event loop implementation:

    Must use the same value of 'session_handle' returned by the preceding 'request_negotiate' or 'listen_negotiate'.
• end_negotiate() This function is used by either ASA in a negotiation session to end a negotiation.
  • Input parameters:
    • asa_handle (unsigned integer)
    • session_handle (structure)
    • result (Boolean)
    • reason (UTF-8 string)
  • Return value:
    • errorcode (unsigned integer)
  • End the negotiation session: 'result' = True for accept (successful negotiation), and False for decline (failed negotiation). 'reason' = string describing reason for decline (may be null; ignored if accept).
  • Asynchronous Mechanisms:

    Threaded implementation:

    Called in the same thread as the preceding 'request_negotiate' or 'listen_negotiate', with the same value of 'session_handle'.

    Event loop implementation:

    Must use the same value of 'session_handle' returned by the preceding 'request_negotiate' or 'listen_negotiate'.

• synchronize() This function is used by any ASA to cause synchronization of a GRASP objective as a requester (client).
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
    • peer (asa_locator)
    • timeout (unsigned integer)
  • Return values:
    • errorcode (unsigned integer)
    • result (structure) (undefined unless successful)
  • This call requests the synchronized value of the given 'objective'.
  • If the 'peer' parameter is null, and the objective is already available in the local cache, the flooded objective is returned immediately in the 'result' parameter. In this case, the 'timeout' is ignored.
  • If the 'peer' parameter is not null, or a cached value is not available, synchronization with a discovered ASA is performed. If successful, the retrieved objective is returned in the 'result' value.
  • The 'peer' parameter is an 'asa_locator' as returned by discover(). If 'peer' is null, GRASP discovery is automatically performed first to find a suitable peer (i.e., any node that supports the objective in question).
  • The 'timeout' parameter is described in Section 2.3.2.3.
  • This call should be repeated whenever the latest value is needed.
  • Asynchronous Mechanisms:

    Threaded implementation:

    Call in a separate thread if asynchronous operation is required.

    Event loop implementation:

    An additional in/out 'session_handle' parameter is used, as in request_negotiate(). If the 'errorcode' parameter has the value 2 ('noReply'), no response has been received so far. The 'session_handle' parameter must be presented in subsequent calls.
  • In the case of failure, an exponential backoff is recommended before retrying (Section 3).
• listen_synchronize() This function is used by an ASA to start acting as a synchronization responder (listener) for a given GRASP objective.
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
  • Return value:
    • errorcode (unsigned integer)
  • This instructs GRASP to listen for synchronization requests for the given objective and to respond with the value given in the 'objective' parameter. It also enables discovery responses for the objective, as mentioned under register_objective() in Section 2.3.3.
  • This call is non-blocking and may be repeated whenever the value changes.
• stop_listen_synchronize() This function is used by an ASA to stop acting as a synchronization responder (listener) for a given GRASP objective.
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
  • Return value:
    • errorcode (unsigned integer)
  • This call instructs GRASP to stop listening for synchronization requests for the given 'objective', i.e., it cancels a previous listen_synchronize.
• flood() This function is used by an ASA to flood one or more GRASP objectives throughout the Autonomic Network. Note that each GRASP node caches all flooded objectives that it receives, until each one's time to live expires. Cached objectives are tagged with their origin as well as an expiry time, so multiple copies of the same objective may be cached simultaneously. Further details are given in "Flood Synchronization Message" (Section 2.8.11 of RFC 8990).
  • Input parameters:
    • asa_handle (unsigned integer)
    • ttl (unsigned integer)
    • tagged_objective_list (structure)
  • Return value:
    • errorcode (unsigned integer)
  • This call instructs GRASP to flood the given synchronization objective(s) and their value(s) and associated locator(s) to all GRASP nodes.
  • The 'ttl' parameter is the valid lifetime (time to live) of the flooded data in milliseconds (0 = infinity).
  • The 'tagged_objective_list' parameter is a list of one or more 'tagged_objective' couplets. The 'locator' parameter that tags each objective is normally null but may be a valid 'asa_locator'. Infrastructure ASAs needing to flood an {address, protocol, port} 3-tuple with an objective create an asa_locator object to do so. If the IP address in that locator is the unspecified address ('::'), it is replaced by the link-local address of the sending node in each copy of the flood multicast, which will be forced to have a loop count of 1. This feature is for objectives that must be restricted to the local link.
  • The function checks that the ASA registered each objective.
  • This call may be repeated whenever any value changes.
• get_flood() This function is used by any ASA to obtain the current value of a flooded GRASP objective.
  • Input parameters:
    • asa_handle (unsigned integer)
    • objective (structure)
  • Return values:
    • errorcode (unsigned integer)
    • tagged_objective_list (structure) (undefined unless successful)
  • This call instructs GRASP to return the given synchronization objective if it has been flooded and its lifetime has not expired.
  • The 'tagged_objective_list' parameter is a list of 'tagged_objective' couplets, each one being a copy of the flooded objective and a corresponding locator. Thus, if the same objective has been flooded by multiple ASAs, the recipient can distinguish the copies.
  • Note that this call is for advanced ASAs. In a simple case, an ASA can simply call synchronize() in order to get a valid flooded objective.
• expire_flood() This function may be used by an ASA to expire specific entries in the local GRASP flood cache.
  • Input parameters:
    • asa_handle (unsigned integer)
    • tagged_objective (structure)
  • Return value:
    • errorcode (unsigned integer)
  • This is a call that can only be used after a preceding call to get_flood() by an ASA that is capable of deciding that the flooded value is stale or invalid. Use with care.
  • The 'tagged_objective' parameter is the one to be expired.

• send_invalid() This function may be used by any ASA to stop an ongoing GRASP session.
  • Input parameters:
    • asa_handle (unsigned integer)
    • session_handle (structure)
    • info (bytes)
  • Return value:
    • errorcode (unsigned integer)
  • Sends a GRASP Invalid message (M_INVALID), as described in [RFC 8990]. It should not be used if end_negotiate() would be sufficient. Note that this message may be used in response to any unicast GRASP message that the receiver cannot interpret correctly. In most cases, this message will be generated internally by a GRASP implementation. 'info' = optional diagnostic data supplied by the ASA. It may be raw bytes from the invalid message.

[RFC8610]

H. Birkholz, C. Vigano, and C. Bormann, "Concise Data Definition Language (CDDL): A Notational Convention to Express Concise Binary Object Representation (CBOR) and JSON Data Structures", RFC 8610, DOI 10.17487/RFC8610, June 2019,
<https://www.rfc-editor.org/info/rfc8610>.

[RFC8949]

C. Bormann, and P. Hoffman, "Concise Binary Object Representation (CBOR)", STD 94, RFC 8949, DOI 10.17487/RFC8949, December 2020,
<https://www.rfc-editor.org/info/rfc8949>.

[RFC8990]

C Bormann, B Carpenter, and B Liu, "GeneRic Autonomic Signaling Protocol (GRASP)", RFC 8990, DOI 10.17487/RFC8990, May 2021,
<https://www.rfc-editor.org/info/rfc8990>.

[ANIMA-COORD]

, and , "Autonomic Functions Coordination", Internet-Draft draft-ciavaglia-anima-coordination-01, March 2016,
<https://tools.ietf.org/html/draft-ciavaglia-anima-coordination-01>.

[ASA-GUIDE]

Nokia, , , , and , "Guidelines for Autonomic Service Agents", Internet-Draft draft-ietf-anima-asa-guidelines-00, November 2020,
<https://tools.ietf.org/html/draft-ietf-anima-asa-guidelines-00>.

[GRASP-DISTRIB]

School of Computer Science, University of Auckland, , , , , , and , "Information Distribution over GRASP", Internet-Draft draft-ietf-anima-grasp-distribution-02, March 2021,
<https://tools.ietf.org/html/draft-ietf-anima-grasp-distribution-02>.

[libcbor]

P Kalvoda, "libcbor - libcbor 0.8.0 documentation", April 2021,
<https://libcbor.readthedocs.io/>.

[RFC8993]

M Behringer, B Carpenter, T Eckert, L Ciavaglia, and J Nobre, "A Reference Model for Autonomic Networking", RFC 8993, DOI 10.17487/RFC8993, May 2021,
<https://www.rfc-editor.org/info/rfc8993>.

[RFC8994]

T Eckert, M Behringer, and S Bjarnason, "An Autonomic Control Plane (ACP)", RFC 8994, DOI 10.17487/RFC8994, May 2021,
<https://www.rfc-editor.org/info/rfc8994>.

[RFC8995]

M Pritikin, M Richardson, T Eckert, M Behringer, and K Watsen, "Bootstrapping Remote Secure Key Infrastructure (BRSKI)", RFC 8995, DOI 10.17487/RFC8995, May 2021,
<https://www.rfc-editor.org/info/rfc8995>.

Brian E. Carpenter

Bing Liu

Wendong Wang

Xiangyang Gong