xref: /openbsd-src/usr.sbin/ldpd/init.c (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
1 /*	$OpenBSD: init.c,v 1.14 2013/10/15 20:21:25 renato Exp $ */
2 
3 /*
4  * Copyright (c) 2009 Michele Marchetto <michele@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/socket.h>
21 #include <sys/uio.h>
22 
23 #include <netinet/in.h>
24 #include <netinet/in_systm.h>
25 #include <netinet/ip.h>
26 #include <arpa/inet.h>
27 #include <net/if_dl.h>
28 #include <unistd.h>
29 
30 #include <errno.h>
31 #include <event.h>
32 #include <stdlib.h>
33 #include <string.h>
34 
35 #include "ldpd.h"
36 #include "ldp.h"
37 #include "log.h"
38 #include "ldpe.h"
39 
40 extern struct ldpd_conf        *leconf;
41 
42 int	gen_init_prms_tlv(struct ibuf *, struct nbr *, u_int16_t);
43 int	tlv_decode_opt_init_prms(char *, u_int16_t);
44 
45 void
46 send_init(struct nbr *nbr)
47 {
48 	struct ibuf		*buf;
49 	u_int16_t		 size;
50 
51 	log_debug("send_init: neighbor ID %s", inet_ntoa(nbr->id));
52 
53 	if ((buf = ibuf_open(LDP_MAX_LEN)) == NULL)
54 		fatal("send_init");
55 
56 	size = LDP_HDR_SIZE + sizeof(struct ldp_msg) + SESS_PRMS_SIZE;
57 
58 	gen_ldp_hdr(buf, size);
59 
60 	size -= LDP_HDR_SIZE;
61 
62 	gen_msg_tlv(buf, MSG_TYPE_INIT, size);
63 
64 	size -= sizeof(struct ldp_msg);
65 
66 	gen_init_prms_tlv(buf, nbr, size);
67 
68 	evbuf_enqueue(&nbr->tcp->wbuf, buf);
69 }
70 
71 int
72 recv_init(struct nbr *nbr, char *buf, u_int16_t len)
73 {
74 	struct ldp_msg		init;
75 	struct sess_prms_tlv	sess;
76 
77 	log_debug("recv_init: neighbor ID %s", inet_ntoa(nbr->id));
78 
79 	bcopy(buf, &init, sizeof(init));
80 
81 	buf += sizeof(struct ldp_msg);
82 	len -= sizeof(struct ldp_msg);
83 
84 	if (len < SESS_PRMS_SIZE) {
85 		session_shutdown(nbr, S_BAD_MSG_LEN, init.msgid, init.type);
86 		return (-1);
87 	}
88 	bcopy(buf, &sess, sizeof(sess));
89 
90 	if (ntohs(sess.length) != SESS_PRMS_SIZE - TLV_HDR_LEN ||
91 	    ntohs(sess.length) > len - TLV_HDR_LEN) {
92 		session_shutdown(nbr, S_BAD_TLV_LEN, init.msgid, init.type);
93 		return (-1);
94 	}
95 
96 	if (ntohs(sess.proto_version) != LDP_VERSION) {
97 		session_shutdown(nbr, S_BAD_PROTO_VER, init.msgid, init.type);
98 		return (-1);
99 	}
100 
101 	buf += SESS_PRMS_SIZE;
102 	len -= SESS_PRMS_SIZE;
103 
104 	/* just ignore all optional TLVs for now */
105 	if (tlv_decode_opt_init_prms(buf, len) == -1) {
106 		session_shutdown(nbr, S_BAD_TLV_VAL, init.msgid, init.type);
107 		return (-1);
108 	}
109 
110 	nbr->keepalive = min(leconf->keepalive, ntohs(sess.keepalive_time));
111 
112 	if (!nbr_pending_idtimer(nbr))
113 		nbr_fsm(nbr, NBR_EVT_INIT_RCVD);
114 
115 	return (ntohs(init.length));
116 }
117 
118 int
119 gen_init_prms_tlv(struct ibuf *buf, struct nbr *nbr, u_int16_t size)
120 {
121 	struct sess_prms_tlv	parms;
122 
123 	/* We want just the size of the value */
124 	size -= TLV_HDR_LEN;
125 
126 	bzero(&parms, sizeof(parms));
127 	parms.type = htons(TLV_TYPE_COMMONSESSION);
128 	parms.length = htons(size);
129 	parms.proto_version = htons(LDP_VERSION);
130 	parms.keepalive_time = htons(leconf->keepalive);
131 	parms.reserved = 0;
132 	parms.pvlim = 0;
133 	parms.max_pdu_len = 0;
134 	parms.lsr_id = nbr->id.s_addr;
135 	parms.lspace_id = 0;
136 
137 	return (ibuf_add(buf, &parms, SESS_PRMS_SIZE));
138 }
139 
140 int
141 tlv_decode_opt_init_prms(char *buf, u_int16_t len)
142 {
143 	struct tlv	tlv;
144 	int		cons = 0;
145 	u_int16_t	tlv_len;
146 
147 	 while (len >= sizeof(tlv)) {
148 		bcopy(buf, &tlv, sizeof(tlv));
149 		tlv_len = ntohs(tlv.length);
150 		switch (ntohs(tlv.type)) {
151 		case TLV_TYPE_ATMSESSIONPAR:
152 			log_warnx("ATM session parameter present");
153 			return (-1);
154 		case TLV_TYPE_FRSESSION:
155 			log_warnx("FR session parameter present");
156 			return (-1);
157 		default:
158 			/* if unknown flag set, ignore TLV */
159 			if (!(ntohs(tlv.type) & UNKNOWN_FLAG))
160 				return (-1);
161 			break;
162 		}
163 		buf += TLV_HDR_LEN + tlv_len;
164 		len -= TLV_HDR_LEN + tlv_len;
165 		cons += TLV_HDR_LEN + tlv_len;
166 	}
167 
168 	return (cons);
169 }
170