1/*
2 * Copyright (c) 2020 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#include <kern/zalloc.h>
29#include <net/if.h>
30#include <net/if_var.h>
31#include <netinet/in.h>
32#include <netinet6/in6_var.h>
33#include <netinet6/in6_ifattach.h>
34#include <netinet/ip6.h>
35#include <netinet6/ip6_var.h>
36#include <netinet6/nd6.h>
37#include <netinet6/scope6_var.h>
38#include <sys/mcache.h>
39
40#define NDRTI_ZONE_NAME "nd6_route_info" /* zone name */
41
42static struct nd_route_info *nd6_rti_lookup(struct nd_route_info *);
43
44static KALLOC_TYPE_DEFINE(ndrti_zone, struct nd_route_info, NET_KT_DEFAULT);
45
46static boolean_t nd6_rti_list_busy = FALSE; /* protected by nd6_mutex */
47
48
49void
50nd6_rti_list_wait(const char *func)
51{
52 LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
53 while (nd6_rti_list_busy) {
54 nd6log2(debug, "%s: someone else is operating "
55 "on rti list. Entering sleep.\n", func);
56 (void) msleep(chan: &nd6_rti_list_busy, nd6_mutex, pri: (PZERO - 1),
57 wmesg: func, NULL);
58 LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
59 }
60 nd6_rti_list_busy = TRUE;
61}
62
63void
64nd6_rti_list_signal_done(void)
65{
66 LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
67 nd6_rti_list_busy = FALSE;
68 wakeup(chan: &nd6_rti_list_busy);
69}
70
71struct nd_route_info *
72ndrti_alloc(void)
73{
74 return zalloc_flags(ndrti_zone, Z_WAITOK | Z_ZERO);
75}
76
77void
78ndrti_free(struct nd_route_info *rti)
79{
80 if (!TAILQ_EMPTY(&rti->nd_rti_router_list)) {
81 panic("%s: rti freed with non-empty router list", __func__);
82 }
83 zfree(ndrti_zone, rti);
84}
85
86static struct nd_route_info *
87nd6_rti_lookup(struct nd_route_info *rti)
88{
89 struct nd_route_info *tmp_rti = NULL;
90
91 LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
92
93 TAILQ_FOREACH(tmp_rti, &nd_rti_list, nd_rti_entry) {
94 if (IN6_ARE_ADDR_EQUAL(&tmp_rti->nd_rti_prefix, &rti->nd_rti_prefix) &&
95 tmp_rti->nd_rti_prefixlen == rti->nd_rti_prefixlen) {
96 break;
97 }
98 }
99 return tmp_rti;
100}
101
102void
103nd6_rtilist_update(struct nd_route_info *new_rti, struct nd_defrouter *dr)
104{
105 struct nd_route_info *rti = NULL;
106
107 lck_mtx_lock(nd6_mutex);
108 VERIFY(new_rti != NULL && dr != NULL);
109 nd6_rti_list_wait(func: __func__);
110
111 if ((rti = nd6_rti_lookup(rti: new_rti)) != NULL) {
112 (void)defrtrlist_update(dr, &rti->nd_rti_router_list);
113 /*
114 * The above may have removed an entry from default router list.
115 * If it did and the list is now empty, remove the rti as well.
116 */
117 if (TAILQ_EMPTY(&rti->nd_rti_router_list)) {
118 TAILQ_REMOVE(&nd_rti_list, rti, nd_rti_entry);
119 ndrti_free(rti);
120 }
121 } else if (dr->rtlifetime != 0) {
122 rti = ndrti_alloc();
123 TAILQ_INIT(&rti->nd_rti_router_list);
124 rti->nd_rti_prefix = new_rti->nd_rti_prefix;
125 rti->nd_rti_prefixlen = new_rti->nd_rti_prefixlen;
126 (void)defrtrlist_update(dr, &rti->nd_rti_router_list);
127 TAILQ_INSERT_HEAD(&nd_rti_list, rti, nd_rti_entry);
128 }
129 /* If rti doesn't exist and lifetime is 0, simply ignore */
130 nd6_rti_list_signal_done();
131 lck_mtx_unlock(nd6_mutex);
132}
133
134void
135nd6_rti_purge(struct nd_route_info *new_rti)
136{
137 VERIFY(new_rti != NULL);
138 LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
139
140 struct nd_route_info *rti = NULL;
141 nd6_rti_list_wait(func: __func__);
142
143 if ((rti = nd6_rti_lookup(rti: new_rti)) != NULL) {
144 struct nd_defrouter *dr = NULL;
145 struct nd_defrouter *ndr = NULL;
146
147 TAILQ_FOREACH_SAFE(dr, &rti->nd_rti_router_list, dr_entry, ndr) {
148 TAILQ_REMOVE(&rti->nd_rti_router_list, dr, dr_entry);
149 defrtrlist_del(dr, &rti->nd_rti_router_list);
150 NDDR_REMREF(dr);
151 }
152 TAILQ_REMOVE(&nd_rti_list, rti, nd_rti_entry);
153 ndrti_free(rti);
154 }
155 nd6_rti_list_signal_done();
156}
157