GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: usr.sbin/ospf6d/packet.c Lines: 0 141 0.0 %
Date: 2017-11-13 Branches: 0 94 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: packet.c,v 1.14 2015/05/05 01:26:37 jsg Exp $ */
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/*
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 * Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
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 *
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 * Permission to use, copy, modify, and distribute this software for any
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 * purpose with or without fee is hereby granted, provided that the above
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 * copyright notice and this permission notice appear in all copies.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 */
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/uio.h>
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#include <netinet/in.h>
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#include <netinet/ip.h>
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#include <netinet/ip6.h>
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#include <arpa/inet.h>
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#include <net/if_dl.h>
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#include <errno.h>
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#include <event.h>
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#include <limits.h>
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#include <stdlib.h>
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#include <string.h>
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#include "ospf6d.h"
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#include "ospf6.h"
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#include "log.h"
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#include "ospfe.h"
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int		 ip_hdr_sanity_check(const struct ip6_hdr *, u_int16_t);
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int		 ospf_hdr_sanity_check(struct ospf_hdr *, u_int16_t,
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		    const struct iface *, struct in6_addr *);
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struct iface	*find_iface(struct ospfd_conf *, unsigned int,
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		    struct in6_addr *);
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int
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gen_ospf_hdr(struct ibuf *buf, struct iface *iface, u_int8_t type)
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{
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	struct ospf_hdr	ospf_hdr;
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	bzero(&ospf_hdr, sizeof(ospf_hdr));
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	ospf_hdr.version = OSPF6_VERSION;
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	ospf_hdr.type = type;
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	ospf_hdr.rtr_id = ospfe_router_id();
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	if (iface->type != IF_TYPE_VIRTUALLINK)
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		ospf_hdr.area_id = iface->area_id.s_addr;
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	ospf_hdr.instance = DEFAULT_INSTANCE_ID;
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	ospf_hdr.zero = 0;		/* must be zero */
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	return (ibuf_add(buf, &ospf_hdr, sizeof(ospf_hdr)));
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}
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int
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upd_ospf_hdr(struct ibuf *buf, struct iface *iface)
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{
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	struct ospf_hdr	*ospf_hdr;
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	if ((ospf_hdr = ibuf_seek(buf, 0, sizeof(*ospf_hdr))) == NULL)
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		fatalx("upd_ospf_hdr: buf_seek failed");
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	/* update length */
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	if (buf->wpos > USHRT_MAX)
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		fatalx("upd_ospf_hdr: resulting ospf packet too big");
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	ospf_hdr->len = htons((u_int16_t)buf->wpos);
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	ospf_hdr->chksum = 0; /* calculated via IPV6_CHECKSUM */
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	return (0);
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}
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/* send and receive packets */
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int
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send_packet(struct iface *iface, void *pkt, size_t len,
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    struct in6_addr *dst)
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{
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	struct sockaddr_in6	 sa6;
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	/* setup buffer */
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	bzero(&sa6, sizeof(sa6));
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	sa6.sin6_family = AF_INET6;
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	sa6.sin6_len = sizeof(sa6);
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	sa6.sin6_addr = *dst;
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	/* don't we all love link local scope and all the needed hacks for it */
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	if (IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MC_LINKLOCAL(dst))
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		sa6.sin6_scope_id = iface->ifindex;
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	/* set outgoing interface for multicast traffic */
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	if (IN6_IS_ADDR_MULTICAST(dst))
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		if (if_set_mcast(iface) == -1) {
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			log_warn("send_packet: error setting multicast "
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			    "interface, %s", iface->name);
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			return (-1);
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		}
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	if (sendto(iface->fd, pkt, len, 0, (struct sockaddr *)&sa6,
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	    sizeof(sa6)) == -1) {
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		log_warn("send_packet: error sending packet on interface %s",
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		    iface->name);
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		return (-1);
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	}
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	return (0);
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}
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void
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recv_packet(int fd, short event, void *bula)
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{
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	union {
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		struct cmsghdr hdr;
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		char	buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
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	} cmsgbuf;
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	struct msghdr		 msg;
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	struct iovec		 iov;
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	struct in6_addr		 addr, dest;
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	struct sockaddr_in6	 src;
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	struct ospfd_conf	*xconf = bula;
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	struct ospf_hdr		*ospf_hdr;
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	struct iface		*iface;
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	struct nbr		*nbr = NULL;
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	char			*buf;
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	struct cmsghdr		*cmsg;
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	ssize_t			 r;
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	u_int16_t		 len;
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	int			 l;
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	unsigned int		 ifindex = 0;
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	if (event != EV_READ)
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		return;
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	/* setup buffer */
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	bzero(&msg, sizeof(msg));
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	iov.iov_base = buf = pkt_ptr;
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	iov.iov_len = READ_BUF_SIZE;
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	msg.msg_name = &src;
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	msg.msg_namelen = sizeof(src);
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	msg.msg_iov = &iov;
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	msg.msg_iovlen = 1;
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	msg.msg_control = &cmsgbuf.buf;
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	msg.msg_controllen = sizeof(cmsgbuf.buf);
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	if ((r = recvmsg(fd, &msg, 0)) == -1) {
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		if (errno != EAGAIN && errno != EINTR)
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			log_debug("recv_packet: read error: %s",
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			    strerror(errno));
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		return;
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	}
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	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
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	    cmsg = CMSG_NXTHDR(&msg, cmsg)) {
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		if (cmsg->cmsg_level == IPPROTO_IPV6 &&
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		    cmsg->cmsg_type == IPV6_PKTINFO) {
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			ifindex = ((struct in6_pktinfo *)
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			    CMSG_DATA(cmsg))->ipi6_ifindex;
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			dest = ((struct in6_pktinfo *)
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			    CMSG_DATA(cmsg))->ipi6_addr;
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			break;
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		}
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	}
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	/* find a matching interface */
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	if ((iface = find_iface(xconf, ifindex, &src.sin6_addr)) == NULL) {
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		/* XXX add a counter here */
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		return;
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	}
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	/*
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	 * Packet needs to be sent to AllSPFRouters or AllDRouters
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	 * or to the address of the interface itself.
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	 * AllDRouters is only valid for DR and BDR but this is checked later.
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	 */
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	inet_pton(AF_INET6, AllSPFRouters, &addr);
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	if (!IN6_ARE_ADDR_EQUAL(&dest, &addr)) {
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		inet_pton(AF_INET6, AllDRouters, &addr);
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		if (!IN6_ARE_ADDR_EQUAL(&dest, &addr)) {
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			if (!IN6_ARE_ADDR_EQUAL(&dest, &iface->addr)) {
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				log_debug("recv_packet: packet sent to wrong "
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				    "address %s, interface %s",
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				    log_in6addr(&dest), iface->name);
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				return;
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			}
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		}
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	}
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	len = (u_int16_t)r;
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	/* OSPF header sanity checks */
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	if (len < sizeof(*ospf_hdr)) {
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		log_debug("recv_packet: bad packet size");
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		return;
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	}
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	ospf_hdr = (struct ospf_hdr *)buf;
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	if ((l = ospf_hdr_sanity_check(ospf_hdr, len, iface, &dest)) == -1)
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		return;
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	nbr = nbr_find_id(iface, ospf_hdr->rtr_id);
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	if (ospf_hdr->type != PACKET_TYPE_HELLO && nbr == NULL) {
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		log_debug("recv_packet: unknown neighbor ID");
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		return;
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	}
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	buf += sizeof(*ospf_hdr);
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	len = l - sizeof(*ospf_hdr);
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	/* switch OSPF packet type */
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	switch (ospf_hdr->type) {
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	case PACKET_TYPE_HELLO:
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		inet_pton(AF_INET6, AllDRouters, &addr);
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		if (IN6_ARE_ADDR_EQUAL(&dest, &addr)) {
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			log_debug("recv_packet: invalid destination IP "
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			     "address");
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			break;
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		}
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		recv_hello(iface, &src.sin6_addr, ospf_hdr->rtr_id, buf, len);
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		break;
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	case PACKET_TYPE_DD:
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		recv_db_description(nbr, buf, len);
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		break;
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	case PACKET_TYPE_LS_REQUEST:
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		recv_ls_req(nbr, buf, len);
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		break;
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	case PACKET_TYPE_LS_UPDATE:
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		recv_ls_update(nbr, buf, len);
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		break;
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	case PACKET_TYPE_LS_ACK:
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		recv_ls_ack(nbr, buf, len);
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		break;
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	default:
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		log_debug("recv_packet: unknown OSPF packet type, interface %s",
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		    iface->name);
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	}
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}
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int
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ospf_hdr_sanity_check(struct ospf_hdr *ospf_hdr, u_int16_t len,
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    const struct iface *iface, struct in6_addr *dst)
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{
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	struct in6_addr		 addr;
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	struct in_addr		 id;
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	if (ospf_hdr->version != OSPF6_VERSION) {
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		log_debug("recv_packet: invalid OSPF version %d",
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		    ospf_hdr->version);
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		return (-1);
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	}
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	if (ntohs(ospf_hdr->len) > len ||
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	    len <= sizeof(struct ospf_hdr)) {
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		log_debug("recv_packet: invalid OSPF packet length %d",
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		    ntohs(ospf_hdr->len));
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		return (-1);
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	}
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	if (iface->type != IF_TYPE_VIRTUALLINK) {
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		if (ospf_hdr->area_id != iface->area_id.s_addr) {
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			id.s_addr = ospf_hdr->area_id;
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			log_debug("recv_packet: invalid area ID %s, "
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			    "interface %s", inet_ntoa(id), iface->name);
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			return (-1);
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		}
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	} else {
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		if (ospf_hdr->area_id != 0) {
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			id.s_addr = ospf_hdr->area_id;
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			log_debug("recv_packet: invalid area ID %s, "
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			    "interface %s", inet_ntoa(id), iface->name);
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			return (-1);
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		}
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	}
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	if (iface->type == IF_TYPE_BROADCAST || iface->type == IF_TYPE_NBMA) {
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		if (inet_pton(AF_INET6, AllDRouters, &addr) == 0)
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			fatalx("recv_packet: inet_pton");
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		if (IN6_ARE_ADDR_EQUAL(dst, &addr) &&
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		    (iface->state & IF_STA_DRORBDR) == 0) {
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			log_debug("recv_packet: invalid destination IP in "
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			    "state %s, interface %s",
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			    if_state_name(iface->state), iface->name);
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			return (-1);
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		}
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	}
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	return (ntohs(ospf_hdr->len));
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}
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struct iface *
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find_iface(struct ospfd_conf *xconf, unsigned int ifindex, struct in6_addr *src)
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{
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	struct area	*area;
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	struct iface	*iface, *match = NULL;
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	/*
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	 * Returned interface needs to be active.
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	 * Virtual-Links have higher precedence so the full interface
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	 * list needs to be scanned for possible matches.
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	 */
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	LIST_FOREACH(area, &xconf->area_list, entry) {
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		LIST_FOREACH(iface, &area->iface_list, entry) {
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			switch (iface->type) {
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			case IF_TYPE_VIRTUALLINK:
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				if (IN6_ARE_ADDR_EQUAL(src, &iface->dst) &&
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				    !(iface->cflags & F_IFACE_PASSIVE))
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					return (iface);
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				break;
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			default:
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				if (ifindex == iface->ifindex &&
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				    !(iface->cflags & F_IFACE_PASSIVE))
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					match = iface;
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				break;
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			}
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		}
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	}
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	return (match);
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}