1/*
2 * Copyright (c) 2004-2021 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29/*
30 * multicast_util.c:
31 * - keep track of multicast addresses added to one interface based on the
32 * actual multicast addresses in another
33 * - used by VLAN and BOND
34 */
35
36/*
37 * Modification History:
38 *
39 * April 29, 2004 Dieter Siegmund (dieter@apple.com)
40 * - created
41 */
42
43#include <net/multicast_list.h>
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/malloc.h>
47#include <net/if_dl.h>
48
49#include <net/sockaddr_utils.h>
50
51__private_extern__ void
52multicast_list_init(struct multicast_list * mc_list)
53{
54 SLIST_INIT(mc_list);
55 return;
56}
57
58/*
59 * Function: multicast_list_remove
60 * Purpose:
61 * Remove the given list of multicast addresses from the interface and from
62 * the multicast list structure.
63 */
64__private_extern__ int
65multicast_list_remove(struct multicast_list * mc_list)
66{
67 int error;
68 struct multicast_entry * mc;
69 int result = 0;
70
71 while ((mc = SLIST_FIRST(mc_list)) != NULL) {
72 error = ifnet_remove_multicast(multicast: mc->mc_ifma);
73 if (error != 0) {
74 result = error;
75 }
76 SLIST_REMOVE_HEAD(mc_list, mc_entries);
77 ifmaddr_release(ifmaddr: mc->mc_ifma);
78 kfree_type(struct multicast_entry, mc);
79 }
80 return result;
81}
82
83/*
84 * Function: multicast_list_program
85 * Purpose:
86 * Program the multicast filter on "target_ifp" using the values from
87 * "source_ifp", and saving the result in "mc_list"
88 *
89 * We build a new list of multicast addresses while programming the new list.
90 * If that completes successfully, we remove the old list, and return the
91 * new list.
92 *
93 * If it fails, we remove what we've added to the new list, and
94 * return an error.
95 */
96__private_extern__ int
97multicast_list_program(struct multicast_list * mc_list,
98 struct ifnet * source_ifp,
99 struct ifnet * target_ifp)
100{
101 u_char alen;
102 int error = 0;
103 int i;
104 struct multicast_entry * mc = NULL;
105 struct multicast_list new_mc_list;
106 struct sockaddr_dl source_sdl = {};
107 ifmultiaddr_t * source_multicast_list;
108 struct sockaddr_dl target_sdl;
109
110 alen = target_ifp->if_addrlen;
111 bzero(s: (char *)&target_sdl, n: sizeof(target_sdl));
112 target_sdl.sdl_len = sizeof(target_sdl);
113 target_sdl.sdl_family = AF_LINK;
114 target_sdl.sdl_type = target_ifp->if_type;
115 target_sdl.sdl_alen = alen;
116 target_sdl.sdl_index = target_ifp->if_index;
117
118 /* build a new list */
119 multicast_list_init(mc_list: &new_mc_list);
120 error = ifnet_get_multicast_list(interface: source_ifp, addresses: &source_multicast_list);
121 if (error != 0) {
122 printf("multicast_list_program: "
123 "ifnet_get_multicast_list(%s%d) failed, %d\n",
124 source_ifp->if_name, source_ifp->if_unit, error);
125 return error;
126 }
127 for (i = 0; source_multicast_list[i] != NULL; i++) {
128 if (ifmaddr_address(ifmaddr: source_multicast_list[i],
129 SA(&source_sdl),
130 addr_size: sizeof(source_sdl)) != 0
131 || source_sdl.sdl_family != AF_LINK) {
132 continue;
133 }
134 mc = kalloc_type(struct multicast_entry, Z_WAITOK | Z_NOFAIL);
135 bcopy(LLADDR(&source_sdl), LLADDR(&target_sdl), n: alen);
136 error = ifnet_add_multicast(interface: target_ifp, SA(&target_sdl),
137 multicast: &mc->mc_ifma);
138 if (error != 0) {
139 kfree_type(struct multicast_entry, mc);
140 break;
141 }
142 SLIST_INSERT_HEAD(&new_mc_list, mc, mc_entries);
143 }
144 if (error != 0) {
145 /* restore previous state */
146 (void)multicast_list_remove(mc_list: &new_mc_list);
147 } else {
148 /* remove the old entries, and return the new list */
149 (void)multicast_list_remove(mc_list);
150 *mc_list = new_mc_list;
151 }
152 ifnet_free_multicast_list(multicasts: source_multicast_list);
153 return error;
154}
155