blob: b0d42dcd82c4912b63c9ccc1e35f659d38176105 [file] [log] [blame]
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -08001/*
2 * Neighbor Discovery snooping for Proxy ARP
3 * Copyright (c) 2014, Qualcomm Atheros, Inc.
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "utils/includes.h"
10#include <netinet/ip6.h>
11#include <netinet/icmp6.h>
12
13#include "utils/common.h"
14#include "l2_packet/l2_packet.h"
15#include "hostapd.h"
16#include "sta_info.h"
17#include "ap_drv_ops.h"
18#include "list.h"
19#include "x_snoop.h"
20
21struct ip6addr {
22 struct in6_addr addr;
23 struct dl_list list;
24};
25
26struct icmpv6_ndmsg {
27 struct ip6_hdr ipv6h;
28 struct icmp6_hdr icmp6h;
29 struct in6_addr target_addr;
30 u8 opt_type;
31 u8 len;
32 u8 opt_lladdr[0];
33} STRUCT_PACKED;
34
35#define ROUTER_ADVERTISEMENT 134
36#define NEIGHBOR_SOLICITATION 135
37#define NEIGHBOR_ADVERTISEMENT 136
38#define SOURCE_LL_ADDR 1
39
40static int sta_ip6addr_add(struct sta_info *sta, struct in6_addr *addr)
41{
42 struct ip6addr *ip6addr;
43
44 ip6addr = os_zalloc(sizeof(*ip6addr));
45 if (!ip6addr)
46 return -1;
47
48 os_memcpy(&ip6addr->addr, addr, sizeof(*addr));
49
50 dl_list_add_tail(&sta->ip6addr, &ip6addr->list);
51
52 return 0;
53}
54
55
56void sta_ip6addr_del(struct hostapd_data *hapd, struct sta_info *sta)
57{
58 struct ip6addr *ip6addr, *prev;
59
60 dl_list_for_each_safe(ip6addr, prev, &sta->ip6addr, struct ip6addr,
61 list) {
62 hostapd_drv_br_delete_ip_neigh(hapd, 6, (u8 *) &ip6addr->addr);
63 os_free(ip6addr);
64 }
65}
66
67
68static int sta_has_ip6addr(struct sta_info *sta, struct in6_addr *addr)
69{
70 struct ip6addr *ip6addr;
71
72 dl_list_for_each(ip6addr, &sta->ip6addr, struct ip6addr, list) {
73 if (ip6addr->addr.s6_addr32[0] == addr->s6_addr32[0] &&
74 ip6addr->addr.s6_addr32[1] == addr->s6_addr32[1] &&
75 ip6addr->addr.s6_addr32[2] == addr->s6_addr32[2] &&
76 ip6addr->addr.s6_addr32[3] == addr->s6_addr32[3])
77 return 1;
78 }
79
80 return 0;
81}
82
83
84static void handle_ndisc(void *ctx, const u8 *src_addr, const u8 *buf,
85 size_t len)
86{
87 struct hostapd_data *hapd = ctx;
88 struct icmpv6_ndmsg *msg;
89 struct in6_addr *saddr;
90 struct sta_info *sta;
91 int res;
92 char addrtxt[INET6_ADDRSTRLEN + 1];
93
94 if (len < ETH_HLEN + sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr))
95 return;
96 msg = (struct icmpv6_ndmsg *) &buf[ETH_HLEN];
97 switch (msg->icmp6h.icmp6_type) {
98 case NEIGHBOR_SOLICITATION:
99 if (len < ETH_HLEN + sizeof(*msg))
100 return;
101 if (msg->opt_type != SOURCE_LL_ADDR)
102 return;
103
104 saddr = &msg->ipv6h.ip6_src;
105 if (!(saddr->s6_addr32[0] == 0 && saddr->s6_addr32[1] == 0 &&
106 saddr->s6_addr32[2] == 0 && saddr->s6_addr32[3] == 0)) {
107 if (len < ETH_HLEN + sizeof(*msg) + ETH_ALEN)
108 return;
109 sta = ap_get_sta(hapd, msg->opt_lladdr);
110 if (!sta)
111 return;
112
113 if (sta_has_ip6addr(sta, saddr))
114 return;
115
116 if (inet_ntop(AF_INET6, saddr, addrtxt, sizeof(addrtxt))
117 == NULL)
118 addrtxt[0] = '\0';
119 wpa_printf(MSG_DEBUG, "ndisc_snoop: Learned new IPv6 address %s for "
120 MACSTR, addrtxt, MAC2STR(sta->addr));
121 hostapd_drv_br_delete_ip_neigh(hapd, 6, (u8 *) saddr);
122 res = hostapd_drv_br_add_ip_neigh(hapd, 6, (u8 *) saddr,
123 128, sta->addr);
124 if (res) {
125 wpa_printf(MSG_ERROR,
126 "ndisc_snoop: Adding ip neigh failed: %d",
127 res);
128 return;
129 }
130
131 if (sta_ip6addr_add(sta, saddr))
132 return;
133 }
134 break;
135 case ROUTER_ADVERTISEMENT:
136 if (!hapd->conf->disable_dgaf)
137 return;
138 /* fall through */
139 case NEIGHBOR_ADVERTISEMENT:
140 for (sta = hapd->sta_list; sta; sta = sta->next) {
141 if (!(sta->flags & WLAN_STA_AUTHORIZED))
142 continue;
143 x_snoop_mcast_to_ucast_convert_send(hapd, sta,
144 (u8 *) buf, len);
145 }
146 break;
147 default:
148 break;
149 }
150}
151
152
153int ndisc_snoop_init(struct hostapd_data *hapd)
154{
155 hapd->sock_ndisc = x_snoop_get_l2_packet(hapd, handle_ndisc,
156 L2_PACKET_FILTER_NDISC);
157 if (hapd->sock_ndisc == NULL) {
158 wpa_printf(MSG_DEBUG,
159 "ndisc_snoop: Failed to initialize L2 packet processing for NDISC packets: %s",
160 strerror(errno));
161 return -1;
162 }
163
164 return 0;
165}
166
167
168void ndisc_snoop_deinit(struct hostapd_data *hapd)
169{
170 l2_packet_deinit(hapd->sock_ndisc);
171}