rfc3542.Advanced Sockets Application Program Inter

NetworkWorkingGroupW.StevensRequestforComments:3542M.ThomasObsoletes:2292ConsultantCategory:InformationalE.NordmarkSunT.JinmeiToshibaMay2003AdvancedSocketsApplicationProgramInterface(API)forIPv6StatusofthisMemoThismemoprovidesinformationfortheInternetcommunity.ItdoesnotspecifyanInternetstandardofanykind.Distributionofthismemoisunlimited.CopyrightNoticeCopyright(C)TheInternetSociety(2003).AllRightsReserved.AbstractThisdocumentprovidessocketsApplicationProgramInterface(API)tosupportadvancedIPv6applications,asasupplementtoaseparatespecification,RFC3493.TheexpectedapplicationsincludePing,Traceroute,routingdaemonsandthelike,whichtypicallyuserawsocketstoaccessIPv6orICMPv6headerfields.ThisdocumentproposessomeportableinterfacesforapplicationsthatuserawsocketsunderIPv6.ThereareotherfeaturesofIPv6thatsomeapplicationswillneedtoaccess:interfaceidentification(specifyingtheoutgoinginterfaceanddeterminingtheincominginterface),IPv6extensionheaders,andpathMaximumTransmissionUnit(MTU)information.ThisdocumentprovidesAPIaccesstothesefeaturestoo.Additionally,someextendedinterfacestolibrariesforthercommandsaredefined.TheextensionwillprovidebetterbackwardcompatibilitytoexistingimplementationsthatarenotIPv6-capable.Stevens,etal.Informational[Page1]RFC3542AdvancedSocketsAPIforIPv6May2003TableofContents1.Introduction..............................................32.CommonStructuresandDefinitions.........................52.1Theip6_hdrStructure................................62.1.1IPv6NextHeaderValues.......................62.1.2IPv6ExtensionHeaders........................72.1.3IPv6Options..................................82.2Theicmp6_hdrStructure..............................102.2.1ICMPv6TypeandCodeValues...................102.2.2ICMPv6NeighborDiscoveryDefinitions.........112.2.3MulticastListenerDiscoveryDefinitions......142.2.4ICMPv6RouterRenumberingDefinitions.........142.3AddressTestingMacros...............................162.4ProtocolsFile.......................................163.IPv6RawSockets..........................................173.1Checksums............................................183.2ICMPv6TypeFiltering................................193.3ICMPv6VerificationofReceivedPackets..............224.AccesstoIPv6andExtensionHeaders......................224.1TCPImplications.....................................244.2UDPandRawSocketImplications......................255.ExtensionstoSocketAncillaryData.......................265.1CMSG_NXTHDR..........................................265.2CMSG_SPACE...........................................265.3CMSG_LEN.............................................276.PacketInformation........................................276.1Specifying/ReceivingtheInterface...................286.2Specifying/ReceivingSource/DestinationAddress......296.3Specifying/ReceivingtheHopLimit...................296.4SpecifyingtheNextHopAddress......................306.5Specifying/ReceivingtheTrafficClassvalue.........316.6AdditionalErrorswithsendmsg()andsetsockopt()....326.7SummaryofOutgoingInterfaceSelection..............327.RoutingHeaderOption.....................................337.1inet6_rth_space......................................357.2inet6_rth_init.......................................357.3inet6_rth_add........................................367.4inet6_rth_reverse....................................367.5inet6_rth_segments...................................367.6inet6_rth_getaddr....................................368.Hop-By-HopOptions........................................378.1ReceivingHop-by-HopOptions.........................388.2SendingHop-by-HopOptions...........................389.DestinationOptions.......................................399.1ReceivingDestinationOptions........................399.2SendingDestinationOptions..........................3910.Hop-by-HopandDestinationOptionsProcessing.............40Stevens,etal.Informational[Page2]RFC3542AdvancedSocketsAPIforIPv6May200310.1inet6_opt_init......................................4110.2inet6_opt_append....................................4110.3inet6_opt_finish....................................4210.4inet6_opt_set_val...................................4210.5inet6_opt_next......................................4210.6inet6_opt_find......................................4310.7inet6_opt_get_val...................................4311.AdditionalAdvancedAPIFunctions.........................4411.1SendingwiththeMinimumMTU........................4411.2SendingwithoutFragmentation.......................4511.3PathMTUDiscoveryandUDP..........................4611.4DeterminingtheCurrentPathMTU....................4712.OrderingofAncillaryDataandIPv6ExtensionHeaders.....4813.IPv6-SpecificOptionswithIPv4-MappedIPv6Addresses.....5014.Extendedinterfacesforrresvport,rcmdandrexec.........5114.1rresvport_af........................................5114.2rcmd_af.............................................5114.3rexec_af............................................5215.SummaryofNewDefinition