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fsm.c revision 1.7
      1 /* $NetBSD: fsm.c,v 1.7 2013/01/26 17:29:55 kefren 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 (at) 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 /* Processing a hello */
     53 void
     54 run_ldp_hello(struct ldp_pdu * pduid, struct hello_tlv * ht,
     55     struct sockaddr * padd, struct in_addr * ladd, int mysock)
     56 {
     57 	struct ldp_peer *peer = NULL;
     58 	union sockunion peer_addr;
     59 	struct transport_address_tlv *trtlv;
     60 	struct hello_info *hi;
     61 
     62 	if ((!pduid) || (!ht))
     63 		return;
     64 
     65 	debugp("Hello received for address: %s\n", inet_ntoa(*ladd));
     66 	debugp("Hello: Type: 0x%.4X Length: %.2d ID: %.8X\n", ht->type,
     67 	    ht->length, ht->messageid);
     68 
     69 	/* Add it to hello list or just update timer */
     70 	SLIST_FOREACH(hi, &hello_info_head, infos)
     71 		if (hi->ldp_id.s_addr == pduid->ldp_id.s_addr)
     72 			break;
     73 	if (hi == NULL) {
     74 		hi = malloc(sizeof(*hi));
     75 		if (!hi) {
     76 			fatalp("Cannot alloc a hello info structure");
     77 			return;
     78 		}
     79 		hi->ldp_id.s_addr = pduid->ldp_id.s_addr;
     80 		SLIST_INSERT_HEAD(&hello_info_head, hi, infos);
     81 	} else
     82 		/* Just update timer */
     83 		hi->keepalive = LDP_HELLO_KEEP;
     84 
     85 	if (ht->length <= 4)	/* Common hello parameters */
     86 		return;
     87 	ht->ch.type = ntohs(ht->ch.type);
     88 	ht->ch.length = ntohs(ht->ch.length);
     89 	ht->ch.holdtime = ntohs(ht->ch.holdtime);
     90 	ht->ch.res = ntohs(ht->ch.res);
     91 	debugp("Common hello Type: 0x%.4X Length: %.2d R:%d T:%d"
     92 	    " Hold time: %d\n", ht->ch.type, ht->ch.length,
     93 	    ht->ch.tr / 2, ht->ch.tr % 2, ht->ch.holdtime);
     94 	if (ht->ch.holdtime != 0)
     95 		hi->keepalive = ht->ch.holdtime;
     96 	else {
     97 		if (ht->ch.res >> 15 == 0)
     98 			hi->keepalive = LDP_HELLO_KEEP;
     99 		else
    100 			hi->keepalive = LDP_THELLO_KEEP;
    101 	}
    102 	if (!get_ldp_peer_by_id(&pduid->ldp_id)) {
    103 		/* Check transport TLV */
    104 		if (pduid->length - PDU_PAYLOAD_LENGTH -
    105 		    sizeof(struct hello_tlv) > 3) {
    106 			trtlv = (struct transport_address_tlv *) &ht[1];
    107 			if (trtlv->type == TLV_IPV4_TRANSPORT) {
    108 				peer_addr.sin.sin_family = AF_INET;
    109 				peer_addr.sin.sin_len =
    110 				    sizeof(struct sockaddr_in);
    111 				memcpy(&peer_addr.sin.sin_addr, &trtlv->address,
    112 				    sizeof(struct in_addr));
    113 			} else if (trtlv->type == TLV_IPV6_TRANSPORT) {
    114 				peer_addr.sin6.sin6_family = AF_INET6;
    115 				peer_addr.sin6.sin6_len =
    116 				    sizeof(struct sockaddr_in6);
    117 				memcpy(&peer_addr.sin6.sin6_addr,
    118 				    &trtlv->address, sizeof(struct in6_addr));
    119 			}
    120 		} else {
    121 			trtlv = NULL;
    122 			peer_addr.sin.sin_family = AF_INET;
    123 			peer_addr.sin.sin_len = sizeof(struct sockaddr_in);
    124 			memcpy(&peer_addr.sin.sin_addr, &pduid->ldp_id,
    125 			    sizeof(struct in_addr));
    126 		}
    127 		/*
    128 		 * RFC 5036 2.5.2: If A1 > A2, LSR1 plays the active role;
    129 		 * otherwise it is passive.
    130 		 */
    131 		/* XXX: check for IPv6 too */
    132 		if (peer_addr.sa.sa_family == AF_INET &&
    133 		    ntohl(peer_addr.sin.sin_addr.s_addr)< ntohl(ladd->s_addr)) {
    134 			peer = ldp_peer_new(&pduid->ldp_id, padd,
    135 				trtlv != NULL ? &peer_addr.sa : NULL,
    136 				ht->ch.holdtime, 0);
    137 			if (!peer)
    138 				return;
    139 			if (peer && peer->state == LDP_PEER_CONNECTED)
    140 				send_initialize(peer);
    141 		}
    142 	}
    143 }
    144 
    145 struct address_list_tlv *
    146 build_address_list_tlv(void)
    147 {
    148 	struct address_list_tlv *t;
    149 	struct ifaddrs *ifa, *ifb;
    150 	struct sockaddr_in *sa;
    151 	struct in_addr *ia;
    152 	uint16_t       adrcount = 0;
    153 
    154 	if (getifaddrs(&ifa) == -1)
    155 		return NULL;
    156 
    157 	/* Find out the number of addresses */
    158 	/* Ignore loopback */
    159 	for (ifb = ifa; ifb; ifb = ifb->ifa_next)
    160 		if ((ifb->ifa_addr->sa_family == AF_INET) &&
    161 		    (ifb->ifa_flags & IFF_UP)) {
    162 			sa = (struct sockaddr_in *) ifb->ifa_addr;
    163 			if (ntohl(sa->sin_addr.s_addr) >> 24 != IN_LOOPBACKNET)
    164 				adrcount++;
    165 		}
    166 	t = malloc(sizeof(*t) + (adrcount - 1) * sizeof(struct in_addr));
    167 
    168 	if (!t) {
    169 		fatalp("build_address_list_tlv: malloc problem\n");
    170 		freeifaddrs(ifa);
    171 		return NULL;
    172 	}
    173 
    174 	t->type = htons(LDP_ADDRESS);
    175 	t->length = htons(sizeof(struct address_list_tlv) - TLV_TYPE_LENGTH
    176 			  + (adrcount - 1) * sizeof(struct in_addr));
    177 	t->messageid = htonl(get_message_id());
    178 
    179 	t->a_type = htons(TLV_ADDRESS_LIST);
    180 	t->a_length = htons(sizeof(t->a_af) +
    181 	    adrcount * sizeof(struct in_addr));
    182 	t->a_af = htons(LDP_AF_INET);
    183 
    184 	ia = &t->a_address;
    185 	for (adrcount = 0, ifb = ifa; ifb; ifb = ifb->ifa_next) {
    186 		if ((ifb->ifa_addr->sa_family != AF_INET) ||
    187 		    (!(ifb->ifa_flags & IFF_UP)) ||
    188 		    (ifb->ifa_flags & IFF_LOOPBACK))
    189 			continue;
    190 		sa = (struct sockaddr_in *) ifb->ifa_addr;
    191 		memcpy(&ia[adrcount], &sa->sin_addr, sizeof(struct in_addr));
    192 		adrcount++;
    193 	}
    194 	freeifaddrs(ifa);
    195 
    196 	add_my_if_addrs(ia, adrcount);
    197 	return t;
    198 }
    199 
    200 /*
    201  * Calculate LDP ID
    202  * Get also mpls pseudo-interface address
    203  */
    204 int
    205 set_my_ldp_id()
    206 {
    207 	struct ifaddrs *ifa, *ifb;
    208 	struct in_addr  a;
    209 	struct sockaddr_in *sa;
    210 
    211 	a.s_addr = 0;
    212 	my_ldp_id[0] = '\0';
    213 	mplssockaddr.sa_len = 0;
    214 
    215 	if (getifaddrs(&ifa) == -1)
    216 		return LDP_E_GENERIC;
    217 
    218 	for (ifb = ifa; ifb; ifb = ifb->ifa_next)
    219 		if(ifb->ifa_flags & IFF_UP) {
    220 			if (strncmp("mpls", ifb->ifa_name, 4) == 0 &&
    221 			    ifb->ifa_addr->sa_family == AF_LINK)
    222 				memcpy(&mplssockaddr, ifb->ifa_addr,
    223 				    ifb->ifa_addr->sa_len);
    224 
    225 			if (ifb->ifa_addr->sa_family != AF_INET)
    226 				continue;
    227 
    228 			sa = (struct sockaddr_in *) ifb->ifa_addr;
    229 			if (ntohl(sa->sin_addr.s_addr) >> 24 == IN_LOOPBACKNET)
    230 				continue;	/* No 127/8 */
    231 			if (ntohl(sa->sin_addr.s_addr) > ntohl(a.s_addr))
    232 				a.s_addr = sa->sin_addr.s_addr;
    233 		}
    234 	freeifaddrs(ifa);
    235 	debugp("LDP ID: %s\n", inet_ntoa(a));
    236 	strlcpy(my_ldp_id, inet_ntoa(a), INET_ADDRSTRLEN);
    237 	return LDP_E_OK;
    238 }
    239