616 lines
15 KiB
C
616 lines
15 KiB
C
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/** @file
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This file implements the RFC2236: IGMP v2.
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Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR>
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SPDX-License-Identifier: BSD-2-Clause-Patent
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**/
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#include "Ip4Impl.h"
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//
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// Route Alert option in IGMP report to direct routers to
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// examine the packet more closely.
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//
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UINT32 mRouteAlertOption = 0x00000494;
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/**
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Init the IGMP control data of the IP4 service instance, configure
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MNP to receive ALL SYSTEM multicast.
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@param[in, out] IpSb The IP4 service whose IGMP is to be initialized.
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@retval EFI_SUCCESS IGMP of the IpSb is successfully initialized.
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@retval EFI_OUT_OF_RESOURCES Failed to allocate resource to initialize IGMP.
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@retval Others Failed to initialize the IGMP of IpSb.
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**/
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EFI_STATUS
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Ip4InitIgmp (
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IN OUT IP4_SERVICE *IpSb
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)
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{
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IGMP_SERVICE_DATA *IgmpCtrl;
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EFI_MANAGED_NETWORK_PROTOCOL *Mnp;
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IGMP_GROUP *Group;
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EFI_STATUS Status;
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IgmpCtrl = &IpSb->IgmpCtrl;
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//
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// Configure MNP to receive ALL_SYSTEM multicast
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//
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Group = AllocatePool (sizeof (IGMP_GROUP));
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if (Group == NULL) {
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return EFI_OUT_OF_RESOURCES;
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}
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Mnp = IpSb->Mnp;
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Group->Address = IP4_ALLSYSTEM_ADDRESS;
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Group->RefCnt = 1;
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Group->DelayTime = 0;
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Group->ReportByUs = FALSE;
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Status = Ip4GetMulticastMac (Mnp, IP4_ALLSYSTEM_ADDRESS, &Group->Mac);
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if (EFI_ERROR (Status)) {
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goto ON_ERROR;
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}
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Status = Mnp->Groups (Mnp, TRUE, &Group->Mac);
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if (EFI_ERROR (Status) && (Status != EFI_ALREADY_STARTED)) {
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goto ON_ERROR;
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}
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InsertHeadList (&IgmpCtrl->Groups, &Group->Link);
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return EFI_SUCCESS;
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ON_ERROR:
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FreePool (Group);
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return Status;
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}
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/**
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Find the IGMP_GROUP structure which contains the status of multicast
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group Address in this IGMP control block
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@param[in] IgmpCtrl The IGMP control block to search from.
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@param[in] Address The multicast address to search.
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@return NULL if the multicast address isn't in the IGMP control block. Otherwise
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the point to the IGMP_GROUP which contains the status of multicast group
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for Address.
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**/
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IGMP_GROUP *
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Ip4FindGroup (
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IN IGMP_SERVICE_DATA *IgmpCtrl,
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IN IP4_ADDR Address
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)
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{
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LIST_ENTRY *Entry;
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IGMP_GROUP *Group;
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NET_LIST_FOR_EACH (Entry, &IgmpCtrl->Groups) {
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Group = NET_LIST_USER_STRUCT (Entry, IGMP_GROUP, Link);
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if (Group->Address == Address) {
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return Group;
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}
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}
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return NULL;
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}
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/**
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Count the number of IP4 multicast groups that are mapped to the
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same MAC address. Several IP4 multicast address may be mapped to
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the same MAC address.
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@param[in] IgmpCtrl The IGMP control block to search in.
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@param[in] Mac The MAC address to search.
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@return The number of the IP4 multicast group that mapped to the same
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multicast group Mac.
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**/
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INTN
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Ip4FindMac (
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IN IGMP_SERVICE_DATA *IgmpCtrl,
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IN EFI_MAC_ADDRESS *Mac
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)
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{
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LIST_ENTRY *Entry;
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IGMP_GROUP *Group;
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INTN Count;
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Count = 0;
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NET_LIST_FOR_EACH (Entry, &IgmpCtrl->Groups) {
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Group = NET_LIST_USER_STRUCT (Entry, IGMP_GROUP, Link);
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if (NET_MAC_EQUAL (&Group->Mac, Mac, sizeof (EFI_MAC_ADDRESS))) {
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Count++;
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}
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}
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return Count;
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}
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/**
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Send an IGMP protocol message to the Dst, such as IGMP v1 membership report.
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@param[in] IpSb The IP4 service instance that requests the
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transmission.
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@param[in] Dst The destinaton to send to.
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@param[in] Type The IGMP message type, such as IGMP v1 membership
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report.
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@param[in] Group The group address in the IGMP message head.
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@retval EFI_OUT_OF_RESOURCES Failed to allocate memory to build the message.
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@retval EFI_SUCCESS The IGMP message is successfully send.
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@retval Others Failed to send the IGMP message.
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**/
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EFI_STATUS
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Ip4SendIgmpMessage (
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IN IP4_SERVICE *IpSb,
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IN IP4_ADDR Dst,
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IN UINT8 Type,
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IN IP4_ADDR Group
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)
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{
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IP4_HEAD Head;
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NET_BUF *Packet;
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IGMP_HEAD *Igmp;
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//
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// Allocate a net buffer to hold the message
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//
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Packet = NetbufAlloc (IP4_MAX_HEADLEN + sizeof (IGMP_HEAD));
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if (Packet == NULL) {
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return EFI_OUT_OF_RESOURCES;
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}
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//
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// Fill in the IGMP and IP header, then transmit the message
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//
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NetbufReserve (Packet, IP4_MAX_HEADLEN);
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Igmp = (IGMP_HEAD *) NetbufAllocSpace (Packet, sizeof (IGMP_HEAD), FALSE);
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if (Igmp == NULL) {
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return EFI_OUT_OF_RESOURCES;
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}
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Igmp->Type = Type;
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Igmp->MaxRespTime = 0;
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Igmp->Checksum = 0;
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Igmp->Group = HTONL (Group);
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Igmp->Checksum = (UINT16) (~NetblockChecksum ((UINT8 *) Igmp, sizeof (IGMP_HEAD)));
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Head.Tos = 0;
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Head.Protocol = IP4_PROTO_IGMP;
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Head.Ttl = 1;
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Head.Fragment = 0;
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Head.Dst = Dst;
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Head.Src = IP4_ALLZERO_ADDRESS;
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return Ip4Output (
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IpSb,
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NULL,
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Packet,
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&Head,
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(UINT8 *) &mRouteAlertOption,
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sizeof (UINT32),
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IP4_ALLZERO_ADDRESS,
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Ip4SysPacketSent,
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NULL
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);
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}
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/**
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Send an IGMP membership report. Depends on whether the server is
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v1 or v2, it will send either a V1 or V2 membership report.
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@param[in] IpSb The IP4 service instance that requests the
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transmission.
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@param[in] Group The group address to report.
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@retval EFI_OUT_OF_RESOURCES Failed to allocate memory to build the message.
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@retval EFI_SUCCESS The IGMP report message is successfully send.
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@retval Others Failed to send the report.
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**/
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EFI_STATUS
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Ip4SendIgmpReport (
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IN IP4_SERVICE *IpSb,
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IN IP4_ADDR Group
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)
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{
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if (IpSb->IgmpCtrl.Igmpv1QuerySeen != 0) {
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return Ip4SendIgmpMessage (IpSb, Group, IGMP_V1_MEMBERSHIP_REPORT, Group);
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} else {
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return Ip4SendIgmpMessage (IpSb, Group, IGMP_V2_MEMBERSHIP_REPORT, Group);
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}
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}
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/**
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Join the multicast group on behalf of this IP4 child
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@param[in] IpInstance The IP4 child that wants to join the group.
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@param[in] Address The group to join.
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@retval EFI_SUCCESS Successfully join the multicast group.
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@retval EFI_OUT_OF_RESOURCES Failed to allocate resources.
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@retval Others Failed to join the multicast group.
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**/
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EFI_STATUS
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Ip4JoinGroup (
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IN IP4_PROTOCOL *IpInstance,
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IN IP4_ADDR Address
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)
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{
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EFI_MANAGED_NETWORK_PROTOCOL *Mnp;
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IP4_SERVICE *IpSb;
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IGMP_SERVICE_DATA *IgmpCtrl;
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IGMP_GROUP *Group;
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EFI_STATUS Status;
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IpSb = IpInstance->Service;
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IgmpCtrl = &IpSb->IgmpCtrl;
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Mnp = IpSb->Mnp;
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//
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// If the IP service already is a member in the group, just
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// increase the refernce count and return.
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//
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Group = Ip4FindGroup (IgmpCtrl, Address);
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if (Group != NULL) {
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Group->RefCnt++;
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return EFI_SUCCESS;
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}
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//
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// Otherwise, create a new IGMP_GROUP, Get the multicast's MAC address,
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// send a report, then direct MNP to receive the multicast.
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//
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Group = AllocatePool (sizeof (IGMP_GROUP));
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if (Group == NULL) {
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return EFI_OUT_OF_RESOURCES;
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}
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Group->Address = Address;
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Group->RefCnt = 1;
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Group->DelayTime = IGMP_UNSOLICIATED_REPORT;
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Group->ReportByUs = TRUE;
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Status = Ip4GetMulticastMac (Mnp, Address, &Group->Mac);
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if (EFI_ERROR (Status)) {
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goto ON_ERROR;
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}
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Status = Ip4SendIgmpReport (IpSb, Address);
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if (EFI_ERROR (Status)) {
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goto ON_ERROR;
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}
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Status = Mnp->Groups (Mnp, TRUE, &Group->Mac);
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if (EFI_ERROR (Status) && (Status != EFI_ALREADY_STARTED)) {
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goto ON_ERROR;
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}
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InsertHeadList (&IgmpCtrl->Groups, &Group->Link);
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return EFI_SUCCESS;
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ON_ERROR:
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FreePool (Group);
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return Status;
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}
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/**
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Leave the IP4 multicast group on behalf of IpInstance.
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@param[in] IpInstance The IP4 child that wants to leave the group
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address.
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@param[in] Address The group address to leave.
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@retval EFI_NOT_FOUND The IP4 service instance isn't in the group.
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@retval EFI_SUCCESS Successfully leave the multicast group.
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@retval Others Failed to leave the multicast group.
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**/
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EFI_STATUS
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Ip4LeaveGroup (
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IN IP4_PROTOCOL *IpInstance,
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IN IP4_ADDR Address
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)
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{
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EFI_MANAGED_NETWORK_PROTOCOL *Mnp;
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IP4_SERVICE *IpSb;
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IGMP_SERVICE_DATA *IgmpCtrl;
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IGMP_GROUP *Group;
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EFI_STATUS Status;
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IpSb = IpInstance->Service;
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IgmpCtrl = &IpSb->IgmpCtrl;
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Mnp = IpSb->Mnp;
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Group = Ip4FindGroup (IgmpCtrl, Address);
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if (Group == NULL) {
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return EFI_NOT_FOUND;
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}
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//
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// If more than one instance is in the group, decrease
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// the RefCnt then return.
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//
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if (--Group->RefCnt > 0) {
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return EFI_SUCCESS;
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}
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//
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// If multiple IP4 group addresses are mapped to the same
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// multicast MAC address, don't configure the MNP to leave
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// the MAC.
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//
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if (Ip4FindMac (IgmpCtrl, &Group->Mac) == 1) {
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Status = Mnp->Groups (Mnp, FALSE, &Group->Mac);
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if (EFI_ERROR (Status) && (Status != EFI_NOT_FOUND)) {
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return Status;
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}
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}
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//
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// Send a leave report if the membership is reported by us
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// and we are talking IGMPv2.
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//
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if (Group->ReportByUs && IgmpCtrl->Igmpv1QuerySeen == 0) {
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Ip4SendIgmpMessage (IpSb, IP4_ALLROUTER_ADDRESS, IGMP_LEAVE_GROUP, Group->Address);
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}
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RemoveEntryList (&Group->Link);
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FreePool (Group);
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return EFI_SUCCESS;
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}
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/**
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Handle the received IGMP message for the IP4 service instance.
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@param[in] IpSb The IP4 service instance that received the message.
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@param[in] Head The IP4 header of the received message.
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@param[in] Packet The IGMP message, without IP4 header.
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@retval EFI_INVALID_PARAMETER The IGMP message is malformated.
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@retval EFI_SUCCESS The IGMP message is successfully processed.
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**/
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EFI_STATUS
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Ip4IgmpHandle (
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IN IP4_SERVICE *IpSb,
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IN IP4_HEAD *Head,
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IN NET_BUF *Packet
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)
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{
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IGMP_SERVICE_DATA *IgmpCtrl;
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IGMP_HEAD Igmp;
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IGMP_GROUP *Group;
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IP4_ADDR Address;
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LIST_ENTRY *Entry;
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IgmpCtrl = &IpSb->IgmpCtrl;
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//
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// Must checksum over the whole packet, later IGMP version
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// may employ message longer than 8 bytes. IP's header has
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// already been trimmed off.
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//
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if ((Packet->TotalSize < sizeof (Igmp)) || (NetbufChecksum (Packet) != 0)) {
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NetbufFree (Packet);
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return EFI_INVALID_PARAMETER;
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}
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//
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// Copy the packet in case it is fragmented
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//
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NetbufCopy (Packet, 0, sizeof (IGMP_HEAD), (UINT8 *)&Igmp);
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switch (Igmp.Type) {
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case IGMP_MEMBERSHIP_QUERY:
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//
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// If MaxRespTime is zero, it is most likely that we are
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// talking to a V1 router
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//
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if (Igmp.MaxRespTime == 0) {
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IgmpCtrl->Igmpv1QuerySeen = IGMP_V1ROUTER_PRESENT;
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Igmp.MaxRespTime = 100;
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}
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//
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// Igmp is ticking once per second but MaxRespTime is in
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// the unit of 100ms.
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//
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Igmp.MaxRespTime /= 10;
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Address = NTOHL (Igmp.Group);
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if (Address == IP4_ALLSYSTEM_ADDRESS) {
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break;
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}
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NET_LIST_FOR_EACH (Entry, &IgmpCtrl->Groups) {
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Group = NET_LIST_USER_STRUCT (Entry, IGMP_GROUP, Link);
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//
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// If address is all zero, all the memberships will be reported.
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// otherwise only one is reported.
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//
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if ((Address == IP4_ALLZERO_ADDRESS) || (Address == Group->Address)) {
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//
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// If the timer is pending, only update it if the time left
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// is longer than the MaxRespTime. TODO: randomize the DelayTime.
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//
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||
|
if ((Group->DelayTime == 0) || (Group->DelayTime > Igmp.MaxRespTime)) {
|
||
|
Group->DelayTime = MAX (1, Igmp.MaxRespTime);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
break;
|
||
|
|
||
|
case IGMP_V1_MEMBERSHIP_REPORT:
|
||
|
case IGMP_V2_MEMBERSHIP_REPORT:
|
||
|
Address = NTOHL (Igmp.Group);
|
||
|
Group = Ip4FindGroup (IgmpCtrl, Address);
|
||
|
|
||
|
if ((Group != NULL) && (Group->DelayTime > 0)) {
|
||
|
Group->DelayTime = 0;
|
||
|
Group->ReportByUs = FALSE;
|
||
|
}
|
||
|
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
NetbufFree (Packet);
|
||
|
return EFI_SUCCESS;
|
||
|
}
|
||
|
|
||
|
|
||
|
/**
|
||
|
The periodical timer function for IGMP. It does the following
|
||
|
things:
|
||
|
1. Decrease the Igmpv1QuerySeen to make it possible to refresh
|
||
|
the IGMP server type.
|
||
|
2. Decrease the report timer for each IGMP group in "delaying
|
||
|
member" state.
|
||
|
|
||
|
@param[in] IpSb The IP4 service instance that is ticking.
|
||
|
|
||
|
**/
|
||
|
VOID
|
||
|
Ip4IgmpTicking (
|
||
|
IN IP4_SERVICE *IpSb
|
||
|
)
|
||
|
{
|
||
|
IGMP_SERVICE_DATA *IgmpCtrl;
|
||
|
LIST_ENTRY *Entry;
|
||
|
IGMP_GROUP *Group;
|
||
|
|
||
|
IgmpCtrl = &IpSb->IgmpCtrl;
|
||
|
|
||
|
if (IgmpCtrl->Igmpv1QuerySeen > 0) {
|
||
|
IgmpCtrl->Igmpv1QuerySeen--;
|
||
|
}
|
||
|
|
||
|
//
|
||
|
// Decrease the report timer for each IGMP group in "delaying member"
|
||
|
//
|
||
|
NET_LIST_FOR_EACH (Entry, &IgmpCtrl->Groups) {
|
||
|
Group = NET_LIST_USER_STRUCT (Entry, IGMP_GROUP, Link);
|
||
|
ASSERT (Group->DelayTime >= 0);
|
||
|
|
||
|
if (Group->DelayTime > 0) {
|
||
|
Group->DelayTime--;
|
||
|
|
||
|
if (Group->DelayTime == 0) {
|
||
|
Ip4SendIgmpReport (IpSb, Group->Address);
|
||
|
Group->ReportByUs = TRUE;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
|
||
|
/**
|
||
|
Add a group address to the array of group addresses.
|
||
|
The caller should make sure that no duplicated address
|
||
|
existed in the array. Although the function doesn't
|
||
|
assume the byte order of the both Source and Addr, the
|
||
|
network byte order is used by the caller.
|
||
|
|
||
|
@param[in] Source The array of group addresses to add to.
|
||
|
@param[in] Count The number of group addresses in the Source.
|
||
|
@param[in] Addr The IP4 multicast address to add.
|
||
|
|
||
|
@return NULL if failed to allocate memory for the new groups,
|
||
|
otherwise the new combined group addresses.
|
||
|
|
||
|
**/
|
||
|
IP4_ADDR *
|
||
|
Ip4CombineGroups (
|
||
|
IN IP4_ADDR *Source,
|
||
|
IN UINT32 Count,
|
||
|
IN IP4_ADDR Addr
|
||
|
)
|
||
|
{
|
||
|
IP4_ADDR *Groups;
|
||
|
|
||
|
Groups = AllocatePool (sizeof (IP4_ADDR) * (Count + 1));
|
||
|
|
||
|
if (Groups == NULL) {
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
CopyMem (Groups, Source, Count * sizeof (IP4_ADDR));
|
||
|
Groups[Count] = Addr;
|
||
|
|
||
|
return Groups;
|
||
|
}
|
||
|
|
||
|
|
||
|
/**
|
||
|
Remove a group address from the array of group addresses.
|
||
|
Although the function doesn't assume the byte order of the
|
||
|
both Groups and Addr, the network byte order is used by
|
||
|
the caller.
|
||
|
|
||
|
@param Groups The array of group addresses to remove from.
|
||
|
@param Count The number of group addresses in the Groups.
|
||
|
@param Addr The IP4 multicast address to remove.
|
||
|
|
||
|
@return The nubmer of group addresses in the Groups after remove.
|
||
|
It is Count if the Addr isn't in the Groups.
|
||
|
|
||
|
**/
|
||
|
INTN
|
||
|
Ip4RemoveGroupAddr (
|
||
|
IN OUT IP4_ADDR *Groups,
|
||
|
IN UINT32 Count,
|
||
|
IN IP4_ADDR Addr
|
||
|
)
|
||
|
{
|
||
|
UINT32 Index;
|
||
|
|
||
|
for (Index = 0; Index < Count; Index++) {
|
||
|
if (Groups[Index] == Addr) {
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
while (Index < Count - 1) {
|
||
|
Groups[Index] = Groups[Index + 1];
|
||
|
Index++;
|
||
|
}
|
||
|
|
||
|
return Index;
|
||
|
}
|