Function route_output

freebsd/net/rtsock.c:988–1182

ARGSUSED*/

/*ARGSUSED*/
static int
route_output(struct mbuf *m, struct socket *so, ...)
{
	struct rt_msghdr *rtm = NULL;
	struct rtentry *rt = NULL;
	struct rt_addrinfo info;
	struct epoch_tracker et;
#ifdef INET6
	struct sockaddr_storage ss;
	struct sockaddr_in6 *sin6;
	int i, rti_need_deembed = 0;
#endif
	int alloc_len = 0, len, error = 0, fibnum;
	sa_family_t saf = AF_UNSPEC;
	struct rib_cmd_info rc;
	struct nhop_object *nh;

	fibnum = so->so_fibnum;
#define senderr(e) { error = e; goto flush;}
	if (m == NULL || ((m->m_len < sizeof(long)) &&
		       (m = m_pullup(m, sizeof(long))) == NULL))
		return (ENOBUFS);
	if ((m->m_flags & M_PKTHDR) == 0)
		panic("route_output");
	NET_EPOCH_ENTER(et);
	len = m->m_pkthdr.len;
	if (len < sizeof(*rtm) ||
	    len != mtod(m, struct rt_msghdr *)->rtm_msglen)
		senderr(EINVAL);

	/*
	 * Most of current messages are in range 200-240 bytes,
	 * minimize possible re-allocation on reply using larger size
	 * buffer aligned on 1k boundaty.
	 */
	alloc_len = roundup2(len, 1024);
	if ((rtm = malloc(alloc_len, M_TEMP, M_NOWAIT)) == NULL)
		senderr(ENOBUFS);

	m_copydata(m, 0, len, (caddr_t)rtm);
	bzero(&info, sizeof(info));
	nh = NULL;

	if (rtm->rtm_version != RTM_VERSION) {
		/* Do not touch message since format is unknown */
		free(rtm, M_TEMP);
		rtm = NULL;
		senderr(EPROTONOSUPPORT);
	}

	/*
	 * Starting from here, it is possible
	 * to alter original message and insert
	 * caller PID and error value.
	 */

	if ((error = fill_addrinfo(rtm, len, fibnum, &info)) != 0) {
		senderr(error);