ICMP_NoMatchAssoc.seq - Ignore the ICMP message if the association cannot be found
To check the receiver silently discard ICMP message if the payload of the ICMP message cannot locate the association.
./ICMP_NoMatchAssoc.seq [-tooloption ...] -pkt ./ICMP_NoMatchAssoc.def -tooloption : v6eval tool option See Also: ../common/STD_PKT_COMMON.def ../common/SCTP_COMMON.def
Association not established between endpoint A and B. Also arrange the data in endpoint B such that upper layers send Associate primitive to startup an association with endpoint A.
Endpoint A Endpoint B ULP (CLOSED) (CLOSED)
<----- Associate <---------------- INIT ICMP -----------------> Silently discard (the association cannot be found) <---------------- INIT
TEST DESCRIPTION:
1. Attempt to terminate an association between endpoint A and endpoint B by sending ICMP message with which association cannot be found. 2. Check A: ICMP message is silently discard. 3. Check B: INIT message is sent again after expiry of T1-Init timer.
None
RFC 4960
Appendix C. ICMP Handling
Whenever an ICMP message is received by an SCTP endpoint, the following procedures MUST be followed to ensure proper utilization of the information being provided by layer 3.
ICMP1) An implementation MAY ignore all ICMPv4 messages where the type field is not set to "Destination Unreachable".
ICMP2) An implementation MAY ignore all ICMPv6 messages where the type field is not "Destination Unreachable", "Parameter Problem",, or "Packet Too Big".
ICMP3) An implementation MAY ignore any ICMPv4 messages where the code does not indicate "Protocol Unreachable" or "Fragmentation Needed".
ICMP4) An implementation MAY ignore all ICMPv6 messages of type "Parameter Problem" if the code is not "Unrecognized Next Header Type Encountered".
ICMP5) An implementation MUST use the payload of the ICMP message (v4 or v6) to locate the association that sent the message to which ICMP is responding. If the association cannot be found, an implementation SHOULD ignore the ICMP message.
ICMP6) An implementation MUST validate that the Verification Tag contained in the ICMP message matches the Verification Tag of the peer. If the Verification Tag is not 0 and does NOT match, discard the ICMP message. If it is 0 and the ICMP message contains enough bytes to verify that the chunk type is an INIT chunk and that the Initiate Tag matches the tag of the peer, continue with ICMP7. If the ICMP message is too short or the chunk type or the Initiate Tag does not match, silently discard the packet.
ICMP7) If the ICMP message is either a v6 "Packet Too Big" or a v4 "Fragmentation Needed", an implementation MAY process this information as defined for PATH MTU discovery.
ICMP8) If the ICMP code is an "Unrecognized Next Header Type Encountered" or a "Protocol Unreachable", an implementation MUST treat this message as an abort with the T bit set if it does not contain an INIT chunk. If it does contain an INIT chunk and the association is in the COOKIE-WAIT state, handle the ICMP message like an ABORT.
ICMP9) If the ICMPv6 code is "Destination Unreachable", the implementation MAY mark the destination into the unreachable state or alternatively increment the path error counter.
Note that these procedures differ from [RFC1122] and from its requirements for processing of port-unreachable messages and the requirements that an implementation MUST abort associations in response to a "protocol unreachable" message. Port-unreachable messages are not processed, since an implementation will send an ABORT, not a port unreachable. The stricter handling of the "protocol unreachable" message is due to security concerns for hosts that do NOT support SCTP.