xref: /openbsd-src/usr.sbin/ldpd/init.c (revision d13be5d47e4149db2549a9828e244d59dbc43f15)
1 /*	$OpenBSD: init.c,v 1.7 2011/01/10 12:02:48 claudio 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 int	gen_init_prms_tlv(struct ibuf *, struct nbr *, u_int16_t);
41 int	tlv_decode_opt_init_prms(char *, u_int16_t);
42 
43 void
44 send_init(struct nbr *nbr)
45 {
46 	struct ibuf		*buf;
47 	u_int16_t		 size;
48 
49 	if (nbr->iface->passive)
50 		return;
51 
52 	log_debug("send_init: neighbor ID %s", inet_ntoa(nbr->id));
53 
54 	if ((buf = ibuf_open(LDP_MAX_LEN)) == NULL)
55 		fatal("send_init");
56 
57 	size = LDP_HDR_SIZE + sizeof(struct ldp_msg) + SESS_PRMS_SIZE;
58 
59 	gen_ldp_hdr(buf, nbr->iface, size);
60 
61 	size -= LDP_HDR_SIZE;
62 
63 	gen_msg_tlv(buf, MSG_TYPE_INIT, size);
64 
65 	size -= sizeof(struct ldp_msg);
66 
67 	gen_init_prms_tlv(buf, nbr, size);
68 
69 	evbuf_enqueue(&nbr->wbuf, buf);
70 }
71 
72 int
73 recv_init(struct nbr *nbr, char *buf, u_int16_t len)
74 {
75 	struct ldp_msg		init;
76 	struct sess_prms_tlv	sess;
77 
78 	log_debug("recv_init: neighbor ID %s", inet_ntoa(nbr->id));
79 
80 	bcopy(buf, &init, sizeof(init));
81 
82 	buf += sizeof(struct ldp_msg);
83 	len -= sizeof(struct ldp_msg);
84 
85 	if (len < SESS_PRMS_SIZE) {
86 		session_shutdown(nbr, S_BAD_MSG_LEN, init.msgid, init.type);
87 		return (-1);
88 	}
89 	bcopy(buf, &sess, sizeof(sess));
90 
91 	if (ntohs(sess.length) != SESS_PRMS_SIZE - TLV_HDR_LEN ||
92 	    ntohs(sess.length) > len - TLV_HDR_LEN) {
93 		session_shutdown(nbr, S_BAD_TLV_LEN, init.msgid, init.type);
94 		return (-1);
95 	}
96 
97 	buf += SESS_PRMS_SIZE;
98 	len -= SESS_PRMS_SIZE;
99 
100 	/* just ignore all optional TLVs for now */
101 	if (tlv_decode_opt_init_prms(buf, len) == -1) {
102 		session_shutdown(nbr, S_BAD_TLV_VAL, init.msgid, init.type);
103 		return (-1);
104 	}
105 
106 	if (nbr->iface->keepalive < ntohs(sess.keepalive_time))
107 		nbr->keepalive = nbr->iface->keepalive;
108 	else
109 		nbr->keepalive = ntohs(sess.keepalive_time);
110 
111 	nbr_fsm(nbr, NBR_EVT_INIT_RCVD);
112 
113 	return (ntohs(init.length));
114 }
115 
116 int
117 gen_init_prms_tlv(struct ibuf *buf, struct nbr *nbr, u_int16_t size)
118 {
119 	struct sess_prms_tlv	parms;
120 
121 	/* We want just the size of the value */
122 	size -= TLV_HDR_LEN;
123 
124 	bzero(&parms, sizeof(parms));
125 	parms.type = htons(TLV_TYPE_COMMONSESSION);
126 	parms.length = htons(size);
127 	parms.proto_version = htons(LDP_VERSION);
128 	parms.keepalive_time = htons(nbr->iface->keepalive);
129 	parms.reserved = 0;
130 	parms.pvlim = 0;
131 	parms.max_pdu_len = 0;
132 	parms.lsr_id = nbr->id.s_addr;
133 	/* XXX: nbr lspace */
134 	parms.lspace_id = 0;
135 
136 	return (ibuf_add(buf, &parms, SESS_PRMS_SIZE));
137 }
138 
139 int
140 tlv_decode_opt_init_prms(char *buf, u_int16_t len)
141 {
142 	struct tlv	tlv;
143 	int		cons = 0;
144 	u_int16_t	tlv_len;
145 
146 	 while (len >= sizeof(tlv)) {
147 		bcopy(buf, &tlv, sizeof(tlv));
148 		tlv_len = ntohs(tlv.length);
149 		switch (ntohs(tlv.type)) {
150 		case TLV_TYPE_ATMSESSIONPAR:
151 			log_warnx("ATM session parameter present");
152 			return (-1);
153 		case TLV_TYPE_FRSESSION:
154 			log_warnx("FR session parameter present");
155 			return (-1);
156 		default:
157 			/* if unknown flag set, ignore TLV */
158 			if (!(ntohs(tlv.type) & UNKNOWN_FLAG))
159 				return (-1);
160 			break;
161 		}
162 		buf += TLV_HDR_LEN + tlv_len;
163 		len -= TLV_HDR_LEN + tlv_len;
164 		cons += TLV_HDR_LEN + tlv_len;
165 	}
166 
167 	return (cons);
168 }
169