1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** NetX Component */
16 /** */
17 /** Internet Group Management Protocol (IGMP) */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22 #define NX_SOURCE_CODE
23
24
25 /* Include necessary system files. */
26
27 #include "nx_api.h"
28 #include "nx_igmp.h"
29
30
31 #ifndef NX_DISABLE_IPV4
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _nx_igmp_multicast_check PORTABLE C */
37 /* 6.1 */
38 /* AUTHOR */
39 /* */
40 /* Yuxin Zhou, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This function checks the list of joined multicast addresses to see */
45 /* if the incoming address matches. If the specified group is */
46 /* "all hosts" or if a match is found, NX_TRUE is returned to the */
47 /* caller. */
48 /* */
49 /* INPUT */
50 /* */
51 /* ip_ptr IP instance pointer */
52 /* group Multicast group IP address */
53 /* nx_interface Pointer to interface */
54 /* */
55 /* OUTPUT */
56 /* */
57 /* NX_TRUE If a match is found */
58 /* NX_FALSE Otherwise */
59 /* */
60 /* CALLS */
61 /* */
62 /* None */
63 /* */
64 /* CALLED BY */
65 /* */
66 /* _nx_ipv4_packet_receive Raw IP packet receive */
67 /* */
68 /* RELEASE HISTORY */
69 /* */
70 /* DATE NAME DESCRIPTION */
71 /* */
72 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */
73 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
74 /* resulting in version 6.1 */
75 /* */
76 /**************************************************************************/
_nx_igmp_multicast_check(NX_IP * ip_ptr,ULONG group,NX_INTERFACE * nx_interface)77 UINT _nx_igmp_multicast_check(NX_IP *ip_ptr, ULONG group, NX_INTERFACE *nx_interface)
78 {
79
80 UINT i;
81
82 /* Check for "all hosts" group. We always assume all hosts membership. */
83 /*lint -e{835} -e{845} suppress operating on zero. */
84 if (group == NX_ALL_HOSTS_ADDRESS)
85 {
86 return(NX_TRUE);
87 }
88
89 /* Loop through the IP multicast join list to find the matching group that is being
90 responded to by another host on this same network. */
91
92 for (i = 0; i < NX_MAX_MULTICAST_GROUPS; i++)
93 {
94
95 /* Check for a match. */
96 if ((ip_ptr -> nx_ipv4_multicast_entry[i].nx_ipv4_multicast_join_list == group) &&
97 (nx_interface == ip_ptr -> nx_ipv4_multicast_entry[i].nx_ipv4_multicast_join_interface_list))
98 {
99 return(NX_TRUE);
100 }
101 }
102
103 /* Otherwise, we have searched the entire list, return false. */
104 return(NX_FALSE);
105 }
106 #endif /* !NX_DISABLE_IPV4 */
107
108
