1 /* $NetBSD: fsm.c,v 1.16 2022/06/26 17:55:38 riastradh Exp $ */
2
3 /*-
4 * Copyright (c) 2010 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Mihai Chelaru <kefren@NetBSD.org>
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/types.h>
33 #include <sys/socket.h>
34 #include <arpa/inet.h>
35 #include <netinet/in.h>
36 #include <net/if.h>
37
38 #include <ifaddrs.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <strings.h>
42
43 #include "ldp.h"
44 #include "ldp_peer.h"
45 #include "socketops.h"
46 #include "ldp_errors.h"
47 #include "fsm.h"
48
49 char my_ldp_id[20];
50 struct sockaddr mplssockaddr;
51
52 /* Process a hello */
53 void
run_ldp_hello(const struct ldp_pdu * pduid,const struct hello_tlv * ht,const struct sockaddr * padd,const struct in_addr * ladd,int mysock,bool may_connect)54 run_ldp_hello(const struct ldp_pdu * pduid, const struct hello_tlv * ht,
55 const struct sockaddr * padd, const struct in_addr * ladd, int mysock,
56 bool may_connect)
57 {
58 struct ldp_peer *peer = NULL;
59 const struct transport_address_tlv *trtlv;
60 struct hello_info *hi = NULL;
61 union sockunion traddr;
62 struct in_addr ldp_id;
63
64 if ((!pduid) || (!ht))
65 return;
66
67 debugp("Hello received for address: %s\n", inet_ntoa(*ladd));
68 debugp("Hello: Type: 0x%.4X Length: %.2d ID: %.8X\n", ht->type,
69 ht->length, ht->messageid);
70
71 if (ht->length <= 4) /* Common hello parameters */
72 return;
73 debugp("Common hello Type: 0x%.4X Length: %.2d"
74 " Hold time: %d\n", ntohs(ht->ch.type), ntohs(ht->ch.length),
75 ht->ch.holdtime);
76
77 memset(&traddr, 0, sizeof(traddr));
78 /* Check transport TLV */
79 if (pduid->length - PDU_PAYLOAD_LENGTH -
80 sizeof(struct hello_tlv) >= 8) {
81 trtlv = (const struct transport_address_tlv *)(ht + 1);
82 if (trtlv->type == htons(TLV_IPV4_TRANSPORT)) {
83 traddr.sin.sin_family = AF_INET;
84 traddr.sin.sin_len = sizeof(struct sockaddr_in);
85 memcpy(&traddr.sin.sin_addr,
86 &trtlv->address, sizeof(struct in_addr));
87 } else if (trtlv->type == htons(TLV_IPV6_TRANSPORT)) {
88 traddr.sin6.sin6_family = AF_INET6;
89 traddr.sin6.sin6_len = sizeof(struct sockaddr_in6);
90 memcpy(&traddr.sin6.sin6_addr,
91 &trtlv->address, sizeof(struct in6_addr));
92 } else
93 warnp("Unknown AF %x for transport address\n",
94 ntohs(trtlv->type));
95 } else {
96 /* Use LDP ID as transport address */
97 traddr.sin.sin_family = AF_INET;
98 traddr.sin.sin_len = sizeof(struct sockaddr_in);
99 memcpy(&traddr.sin.sin_addr,
100 &pduid->ldp_id, sizeof(struct in_addr));
101 }
102 /* Add it to hello list or just update timer */
103 SLIST_FOREACH(hi, &hello_info_head, infos)
104 if (hi->ldp_id.s_addr == pduid->ldp_id.s_addr &&
105 sockaddr_cmp(&hi->transport_address.sa, &traddr.sa) == 0)
106 break;
107 if (hi == NULL) {
108 hi = calloc(1, sizeof(*hi));
109 if (!hi) {
110 fatalp("Cannot alloc a hello info structure");
111 return;
112 }
113 hi->ldp_id.s_addr = pduid->ldp_id.s_addr;
114 memcpy(&hi->transport_address, &traddr, traddr.sa.sa_len);
115 SLIST_INSERT_HEAD(&hello_info_head, hi, infos);
116 may_connect = false;
117 }
118
119 /* Update expire timer */
120 if (ht->ch.holdtime != 0)
121 hi->keepalive = ntohs(ht->ch.holdtime);
122 else {
123 if (ntohs(ht->ch.res) >> 15 == 0)
124 hi->keepalive = LDP_HELLO_KEEP;
125 else
126 hi->keepalive = LDP_THELLO_KEEP;
127 }
128
129 ldp_id = pduid->ldp_id;
130 if (!get_ldp_peer_by_id(&ldp_id)) {
131 /*
132 * RFC 5036 2.5.2: If A1 > A2, LSR1 plays the active role;
133 * otherwise it is passive.
134 */
135 if (may_connect == true &&
136 (hi->transport_address.sa.sa_family == AF_INET &&
137 ntohl(hi->transport_address.sin.sin_addr.s_addr) <
138 ntohl(ladd->s_addr))) {
139 peer = ldp_peer_new(&ldp_id, padd,
140 &hi->transport_address.sa,
141 ntohs(ht->ch.holdtime), 0);
142 if (peer == NULL)
143 return;
144 if (peer->state == LDP_PEER_CONNECTED)
145 send_initialize(peer);
146 }
147 }
148 }
149
150 struct address_list_tlv *
build_address_list_tlv(void)151 build_address_list_tlv(void)
152 {
153 struct address_list_tlv *t;
154 struct ifaddrs *ifa, *ifb;
155 struct sockaddr_in *sa;
156 char *ia;
157 uint16_t adrcount = 0;
158
159 if (getifaddrs(&ifa) == -1)
160 return NULL;
161
162 /* Find out the number of addresses */
163 /* Ignore loopback */
164 for (ifb = ifa; ifb; ifb = ifb->ifa_next)
165 if ((ifb->ifa_addr->sa_family == AF_INET) &&
166 (ifb->ifa_flags & IFF_UP)) {
167 sa = (struct sockaddr_in *) ifb->ifa_addr;
168 if (ntohl(sa->sin_addr.s_addr) >> 24 != IN_LOOPBACKNET)
169 adrcount++;
170 }
171 t = malloc(sizeof(*t) + (adrcount - 1) * sizeof(struct in_addr));
172
173 if (!t) {
174 fatalp("build_address_list_tlv: malloc problem\n");
175 freeifaddrs(ifa);
176 return NULL;
177 }
178
179 t->type = htons(LDP_ADDRESS);
180 t->length = htons(sizeof(struct address_list_tlv) - TLV_TYPE_LENGTH
181 + (adrcount - 1) * sizeof(struct in_addr));
182 t->messageid = htonl(get_message_id());
183
184 t->a_type = htons(TLV_ADDRESS_LIST);
185 t->a_length = htons(sizeof(t->a_af) +
186 adrcount * sizeof(struct in_addr));
187 t->a_af = htons(LDP_AF_INET);
188
189 ia = (void *)&t->a_address;
190 for (adrcount = 0, ifb = ifa; ifb; ifb = ifb->ifa_next) {
191 if ((ifb->ifa_addr->sa_family != AF_INET) ||
192 (!(ifb->ifa_flags & IFF_UP)))
193 continue;
194 sa = (struct sockaddr_in *) ifb->ifa_addr;
195 if (ntohl(sa->sin_addr.s_addr) >> 24 == IN_LOOPBACKNET)
196 continue;
197 memcpy(ia + adrcount*sizeof(struct in_addr), &sa->sin_addr,
198 sizeof(struct in_addr));
199 adrcount++;
200 }
201 freeifaddrs(ifa);
202
203 return t;
204 }
205
206 /*
207 * Calculate LDP ID
208 * Get also mpls pseudo-interface address
209 */
210 int
set_my_ldp_id()211 set_my_ldp_id()
212 {
213 struct ifaddrs *ifa, *ifb;
214 struct in_addr a;
215 struct sockaddr_in *sa;
216
217 a.s_addr = 0;
218 my_ldp_id[0] = '\0';
219 mplssockaddr.sa_len = 0;
220
221 if (getifaddrs(&ifa) == -1)
222 return LDP_E_GENERIC;
223
224 for (ifb = ifa; ifb; ifb = ifb->ifa_next)
225 if(ifb->ifa_flags & IFF_UP) {
226 if (strncmp("mpls", ifb->ifa_name, 4) == 0 &&
227 ifb->ifa_addr->sa_family == AF_LINK)
228 memcpy(&mplssockaddr, ifb->ifa_addr,
229 ifb->ifa_addr->sa_len);
230
231 if (ifb->ifa_addr->sa_family != AF_INET)
232 continue;
233
234 sa = (struct sockaddr_in *) ifb->ifa_addr;
235 if (ntohl(sa->sin_addr.s_addr) >> 24 == IN_LOOPBACKNET)
236 continue; /* No 127/8 */
237 if (ntohl(sa->sin_addr.s_addr) > ntohl(a.s_addr))
238 a.s_addr = sa->sin_addr.s_addr;
239 }
240 freeifaddrs(ifa);
241 debugp("LDP ID: %s\n", inet_ntoa(a));
242 strlcpy(my_ldp_id, inet_ntoa(a), INET_ADDRSTRLEN);
243 setproctitle("LDP ID: %s", my_ldp_id);
244 return LDP_E_OK;
245 }
246