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[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [libnetworking/] [netinet/] [ip_input.c] - Blame information for rev 773

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/*
 * Copyright (c) 1982, 1986, 1988, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)ip_input.c  8.2 (Berkeley) 1/4/94
 * $Id: ip_input.c,v 1.2 2001-09-27 12:01:55 chris Exp $
 *      $ANA: ip_input.c,v 1.5 1996/09/18 14:34:59 wollman Exp $
 */
 
#define _IP_VHL
 
#include "opt_ipfw.h"
 
#include <stddef.h>
 
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/sysctl.h>
 
#include <net/if.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/netisr.h>
 
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/in_var.h>
#include <netinet/ip_var.h>
#include <netinet/ip_icmp.h>
#include <machine/in_cksum.h>
 
#include <sys/socketvar.h>
 
#ifdef IPFIREWALL
#include <netinet/ip_fw.h>
#endif
 
int rsvp_on = 0;
static int ip_rsvp_on;
struct socket *ip_rsvpd;
 
static int      ipforwarding = 0;
SYSCTL_INT(_net_inet_ip, IPCTL_FORWARDING, forwarding, CTLFLAG_RW,
        &ipforwarding, 0, "");
 
static int      ipsendredirects = 1; /* XXX */
SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_RW,
        &ipsendredirects, 0, "");
 
int     ip_defttl = IPDEFTTL;
SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_RW,
        &ip_defttl, 0, "");
 
static int      ip_dosourceroute = 0;
SYSCTL_INT(_net_inet_ip, IPCTL_SOURCEROUTE, sourceroute, CTLFLAG_RW,
        &ip_dosourceroute, 0, "");
 
static int      ip_acceptsourceroute = 0;
SYSCTL_INT(_net_inet_ip, IPCTL_ACCEPTSOURCEROUTE, accept_sourceroute,
        CTLFLAG_RW, &ip_acceptsourceroute, 0, "");
#ifdef DIAGNOSTIC
static int      ipprintfs = 0;
#endif
 
extern  struct domain inetdomain;
extern  struct protosw inetsw[];
u_char  ip_protox[IPPROTO_MAX];
static int      ipqmaxlen = IFQ_MAXLEN;
struct  in_ifaddr *in_ifaddr;                   /* first inet address */
struct  ifqueue ipintrq;
SYSCTL_INT(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen, CTLFLAG_RD,
        &ipintrq.ifq_maxlen, 0, "");
SYSCTL_INT(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops, CTLFLAG_RD,
        &ipintrq.ifq_drops, 0, "");
 
struct ipstat ipstat;
 
/* Packet reassembly stuff */
#define IPREASS_NHASH_LOG2      6
#define IPREASS_NHASH           (1 << IPREASS_NHASH_LOG2)
#define IPREASS_HMASK           (IPREASS_NHASH - 1)
#define IPREASS_HASH(x,y) \
        (((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK)
 
static struct ipq ipq[IPREASS_NHASH];
static int    nipq = 0;         /* total # of reass queues */
static int    maxnipq;
 
#ifdef IPCTL_DEFMTU
SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW,
        &ip_mtu, 0, "");
#endif
 
#if !defined(COMPAT_IPFW) || COMPAT_IPFW == 1
#undef COMPAT_IPFW
#define COMPAT_IPFW 1
#else
#undef COMPAT_IPFW
#endif
 
#ifdef COMPAT_IPFW
/* Firewall hooks */
ip_fw_chk_t *ip_fw_chk_ptr;
ip_fw_ctl_t *ip_fw_ctl_ptr;
 
/* IP Network Address Translation (NAT) hooks */
ip_nat_t *ip_nat_ptr;
ip_nat_ctl_t *ip_nat_ctl_ptr;
#endif
 
/*
 * We need to save the IP options in case a protocol wants to respond
 * to an incoming packet over the same route if the packet got here
 * using IP source routing.  This allows connection establishment and
 * maintenance when the remote end is on a network that is not known
 * to us.
 */
static int      ip_nhops = 0;
static  struct ip_srcrt {
        struct  in_addr dst;                    /* final destination */
        char    nop;                            /* one NOP to align */
        char    srcopt[IPOPT_OFFSET + 1];       /* OPTVAL, OLEN and OFFSET */
        struct  in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)];
} ip_srcrt;
 
#ifdef IPDIVERT
/*
 * Shared variable between ip_input() and ip_reass() to communicate
 * about which packets, once assembled from fragments, get diverted,
 * and to which port.
 */
static u_short  frag_divert_port;
#endif
 
static void save_rte __P((u_char *, struct in_addr));
static void      ip_deq __P((struct ipasfrag *));
static int       ip_dooptions __P((struct mbuf *));
static void      ip_enq __P((struct ipasfrag *, struct ipasfrag *));
static void      ip_forward __P((struct mbuf *, int));
static void      ip_freef __P((struct ipq *));
static struct ip *
         ip_reass __P((struct ipasfrag *, struct ipq *, struct ipq *));
static struct in_ifaddr *
         ip_rtaddr __P((struct in_addr));
void    ipintr __P((void));
/*
 * IP initialization: fill in IP protocol switch table.
 * All protocols not implemented in kernel go to raw IP protocol handler.
 */
void
ip_init()
{
        register struct protosw *pr;
        register int i;
 
        pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
        if (pr == 0)
                panic("ip_init");
        for (i = 0; i < IPPROTO_MAX; i++)
                ip_protox[i] = pr - inetsw;
        for (pr = inetdomain.dom_protosw;
            pr < inetdomain.dom_protoswNPROTOSW; pr++)
                if (pr->pr_domain->dom_family == PF_INET &&
                    pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW)
                        ip_protox[pr->pr_protocol] = pr - inetsw;
 
        for (i = 0; i < IPREASS_NHASH; i++)
            ipq[i].next = ipq[i].prev = &ipq[i];
 
        maxnipq = nmbclusters/4;
 
        ip_id = rtems_bsdnet_seconds_since_boot() & 0xffff;
        ipintrq.ifq_maxlen = ipqmaxlen;
#ifdef IPFIREWALL
        ip_fw_init();
#endif
#ifdef IPNAT
        ip_nat_init();
#endif
 
}
 
static struct   sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET };
static struct   route ipforward_rt;
 
/*
 * Ip input routine.  Checksum and byte swap header.  If fragmented
 * try to reassemble.  Process options.  Pass to next level.
 */
void
ip_input(struct mbuf *m)
{
        struct ip *ip;
        struct ipq *fp;
        struct in_ifaddr *ia;
        int    i, hlen;
        u_short sum;
 
#ifdef  DIAGNOSTIC
        if ((m->m_flags & M_PKTHDR) == 0)
                panic("ip_input no HDR");
#endif
        /*
         * If no IP addresses have been set yet but the interfaces
         * are receiving, can't do anything with incoming packets yet.
         */
        if (in_ifaddr == NULL)
                goto bad;
        ipstat.ips_total++;
 
        if (m->m_pkthdr.len < sizeof(struct ip))
                goto tooshort;
 
#if defined(DIAGNOSTIC) && defined(ORIGINAL_FREEBSD_CODE)
        if (m->m_len < sizeof(struct ip))
                panic("ipintr mbuf too short");
#endif
 
        if (m->m_len < sizeof (struct ip) &&
            (m = m_pullup(m, sizeof (struct ip))) == 0) {
                ipstat.ips_toosmall++;
                return;
        }
        ip = mtod(m, struct ip *);
 
        if (IP_VHL_V(ip->ip_vhl) != IPVERSION) {
                ipstat.ips_badvers++;
                goto bad;
        }
 
        hlen = IP_VHL_HL(ip->ip_vhl) << 2;
        if (hlen < sizeof(struct ip)) { /* minimum header length */
                ipstat.ips_badhlen++;
                goto bad;
        }
        if (hlen > m->m_len) {
                if ((m = m_pullup(m, hlen)) == 0) {
                        ipstat.ips_badhlen++;
                        return;
                }
                ip = mtod(m, struct ip *);
        }
        if (hlen == sizeof(struct ip)) {
                sum = in_cksum_hdr(ip);
        } else {
                sum = in_cksum(m, hlen);
        }
        if (sum) {
                ipstat.ips_badsum++;
                goto bad;
        }
 
        /*
         * Convert fields to host representation.
         */
        NTOHS(ip->ip_len);
        if (ip->ip_len < hlen) {
                ipstat.ips_badlen++;
                goto bad;
        }
        NTOHS(ip->ip_id);
        NTOHS(ip->ip_off);
 
        /*
         * Check that the amount of data in the buffers
         * is as at least much as the IP header would have us expect.
         * Trim mbufs if longer than we expect.
         * Drop packet if shorter than we expect.
         */
        if (m->m_pkthdr.len < ip->ip_len) {
tooshort:
                ipstat.ips_tooshort++;
                goto bad;
        }
        if (m->m_pkthdr.len > ip->ip_len) {
                if (m->m_len == m->m_pkthdr.len) {
                        m->m_len = ip->ip_len;
                        m->m_pkthdr.len = ip->ip_len;
                } else
                        m_adj(m, ip->ip_len - m->m_pkthdr.len);
        }
        /*
         * IpHack's section.
         * Right now when no processing on packet has done
         * and it is still fresh out of network we do our black
         * deals with it.
         * - Firewall: deny/allow/divert
         * - Xlate: translate packet's addr/port (NAT).
         * - Wrap: fake packet's addr/port <unimpl.>
         * - Encapsulate: put it in another IP and send out. <unimp.>
         */
 
#ifdef COMPAT_IPFW
        if (ip_fw_chk_ptr) {
#ifdef IPDIVERT
                u_short port;
 
                port = (*ip_fw_chk_ptr)(&ip, hlen, NULL, ip_divert_ignore, &m);
                ip_divert_ignore = 0;
                if (port) {                     /* Divert packet */
                        frag_divert_port = port;
                        goto ours;
                }
#else
                /* If ipfw says divert, we have to just drop packet */
                if ((*ip_fw_chk_ptr)(&ip, hlen, NULL, 0, &m)) {
                        m_freem(m);
                        m = NULL;
                }
#endif
                if (!m)
                        return;
        }
 
        if (ip_nat_ptr && !(*ip_nat_ptr)(&ip, &m, m->m_pkthdr.rcvif, IP_NAT_IN))
                return;
#endif
 
        /*
         * Process options and, if not destined for us,
         * ship it on.  ip_dooptions returns 1 when an
         * error was detected (causing an icmp message
         * to be sent and the original packet to be freed).
         */
        ip_nhops = 0;            /* for source routed packets */
        if (hlen > sizeof (struct ip) && ip_dooptions(m))
                return;
 
        /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no
         * matter if it is destined to another node, or whether it is
         * a multicast one, RSVP wants it! and prevents it from being forwarded
         * anywhere else. Also checks if the rsvp daemon is running before
         * grabbing the packet.
         */
        if (rsvp_on && ip->ip_p==IPPROTO_RSVP)
                goto ours;
 
        /*
         * Check our list of addresses, to see if the packet is for us.
         */
        for (ia = in_ifaddr; ia; ia = ia->ia_next) {
#define satosin(sa)     ((struct sockaddr_in *)(sa))
 
                if (IA_SIN(ia)->sin_addr.s_addr == ip->ip_dst.s_addr)
                        goto ours;
#ifdef BOOTP_COMPAT
                if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY)
                        goto ours;
#endif
                if (ia->ia_ifp && ia->ia_ifp->if_flags & IFF_BROADCAST) {
                        if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
                            ip->ip_dst.s_addr)
                                goto ours;
                        if (ip->ip_dst.s_addr == ia->ia_netbroadcast.s_addr)
                                goto ours;
                }
        }
        if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
                struct in_multi *inm;
                if (ip_mrouter) {
                        /*
                         * If we are acting as a multicast router, all
                         * incoming multicast packets are passed to the
                         * kernel-level multicast forwarding function.
                         * The packet is returned (relatively) intact; if
                         * ip_mforward() returns a non-zero value, the packet
                         * must be discarded, else it may be accepted below.
                         *
                         * (The IP ident field is put in the same byte order
                         * as expected when ip_mforward() is called from
                         * ip_output().)
                         */
                        ip->ip_id = htons(ip->ip_id);
                        if (ip_mforward(ip, m->m_pkthdr.rcvif, m, 0) != 0) {
                                ipstat.ips_cantforward++;
                                m_freem(m);
                                return;
                        }
                        ip->ip_id = ntohs(ip->ip_id);
 
                        /*
                         * The process-level routing demon needs to receive
                         * all multicast IGMP packets, whether or not this
                         * host belongs to their destination groups.
                         */
                        if (ip->ip_p == IPPROTO_IGMP)
                                goto ours;
                        ipstat.ips_forward++;
                }
                /*
                 * See if we belong to the destination multicast group on the
                 * arrival interface.
                 */
                IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
                if (inm == NULL) {
                        ipstat.ips_cantforward++;
                        m_freem(m);
                        return;
                }
                goto ours;
        }
        if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST)
                goto ours;
        if (ip->ip_dst.s_addr == INADDR_ANY)
                goto ours;
 
        /*
         * Not for us; forward if possible and desirable.
         */
        if (ipforwarding == 0) {
                ipstat.ips_cantforward++;
                m_freem(m);
        } else
                ip_forward(m, 0);
        return;
 
ours:
 
        /*
         * If offset or IP_MF are set, must reassemble.
         * Otherwise, nothing need be done.
         * (We could look in the reassembly queue to see
         * if the packet was previously fragmented,
         * but it's not worth the time; just let them time out.)
         */
        if (ip->ip_off &~ (IP_DF | IP_RF)) {
                if (m->m_flags & M_EXT) {               /* XXX */
                        if ((m = m_pullup(m, sizeof (struct ip))) == 0) {
                                ipstat.ips_toosmall++;
#ifdef IPDIVERT
                                frag_divert_port = 0;
#endif
                                return;
                        }
                        ip = mtod(m, struct ip *);
                }
                sum = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id);
                /*
                 * Look for queue of fragments
                 * of this datagram.
                 */
                for (fp = ipq[sum].next; fp != &ipq[sum]; fp = fp->next)
                        if (ip->ip_id == fp->ipq_id &&
                            ip->ip_src.s_addr == fp->ipq_src.s_addr &&
                            ip->ip_dst.s_addr == fp->ipq_dst.s_addr &&
                            ip->ip_p == fp->ipq_p)
                                goto found;
 
                fp = 0;
 
                /* check if there's a place for the new queue */
                if (nipq > maxnipq) {
                    /*
                     * drop something from the tail of the current queue
                     * before proceeding further
                     */
                    if (ipq[sum].prev == &ipq[sum]) {   /* gak */
                        for (i = 0; i < IPREASS_NHASH; i++) {
                            if (ipq[i].prev != &ipq[i]) {
                                ip_freef(ipq[i].prev);
                                break;
                            }
                        }
                    } else
                        ip_freef(ipq[sum].prev);
                }
found:
                /*
                 * Adjust ip_len to not reflect header,
                 * set ip_mff if more fragments are expected,
                 * convert offset of this to bytes.
                 */
                ip->ip_len -= hlen;
                ((struct ipasfrag *)ip)->ipf_mff &= ~1;
                if (ip->ip_off & IP_MF)
                        ((struct ipasfrag *)ip)->ipf_mff |= 1;
                ip->ip_off <<= 3;
 
                /*
                 * If datagram marked as having more fragments
                 * or if this is not the first fragment,
                 * attempt reassembly; if it succeeds, proceed.
                 */
                if (((struct ipasfrag *)ip)->ipf_mff & 1 || ip->ip_off) {
                        ipstat.ips_fragments++;
                        ip = ip_reass((struct ipasfrag *)ip, fp, &ipq[sum]);
                        if (ip == 0)
                                return;
                        ipstat.ips_reassembled++;
                        m = dtom(ip);
#ifdef IPDIVERT
                        if (frag_divert_port) {
                                ip->ip_len += hlen;
                                HTONS(ip->ip_len);
                                HTONS(ip->ip_off);
                                HTONS(ip->ip_id);
                                ip->ip_sum = 0;
                                ip->ip_sum = in_cksum_hdr(ip);
                                NTOHS(ip->ip_id);
                                NTOHS(ip->ip_off);
                                NTOHS(ip->ip_len);
                                ip->ip_len -= hlen;
                        }
#endif
                } else
                        if (fp)
                                ip_freef(fp);
        } else
                ip->ip_len -= hlen;
 
#ifdef IPDIVERT
        /*
         * Divert reassembled packets to the divert protocol if required
         */
        if (frag_divert_port) {
                ipstat.ips_delivered++;
                ip_divert_port = frag_divert_port;
                frag_divert_port = 0;
                (*inetsw[ip_protox[IPPROTO_DIVERT]].pr_input)(m, hlen);
                return;
        }
 
        /* Don't let packets divert themselves */
        if (ip->ip_p == IPPROTO_DIVERT) {
                ipstat.ips_noproto++;
                goto bad;
        }
#endif
 
        /*
         * Switch out to protocol's input routine.
         */
        ipstat.ips_delivered++;
        (*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen);
        return;
bad:
        m_freem(m);
}
 
/*
 * IP software interrupt routine - to go away sometime soon
 */
void
ipintr(void)
{
        int s;
        struct mbuf *m;
 
        while(1) {
                s = splimp();
                IF_DEQUEUE(&ipintrq, m);
                splx(s);
                if (m == 0)
                        return;
                ip_input(m);
        }
}
 
NETISR_SET(NETISR_IP, ipintr);
 
/*
 * Take incoming datagram fragment and try to
 * reassemble it into whole datagram.  If a chain for
 * reassembly of this datagram already exists, then it
 * is given as fp; otherwise have to make a chain.
 */
static struct ip *
ip_reass(ip, fp, where)
        register struct ipasfrag *ip;
        register struct ipq *fp;
        struct   ipq    *where;
{
        register struct mbuf *m = dtom(ip);
        register struct ipasfrag *q;
        struct mbuf *t;
        int hlen = ip->ip_hl << 2;
        int i, next;
 
        /*
         * Presence of header sizes in mbufs
         * would confuse code below.
         */
        m->m_data += hlen;
        m->m_len -= hlen;
 
        /*
         * If first fragment to arrive, create a reassembly queue.
         */
        if (fp == 0) {
                if ((t = m_get(M_DONTWAIT, MT_FTABLE)) == NULL)
                        goto dropfrag;
                fp = mtod(t, struct ipq *);
                insque(fp, where);
                nipq++;
                fp->ipq_ttl = IPFRAGTTL;
                fp->ipq_p = ip->ip_p;
                fp->ipq_id = ip->ip_id;
                fp->ipq_next = fp->ipq_prev = (struct ipasfrag *)fp;
                fp->ipq_src = ((struct ip *)ip)->ip_src;
                fp->ipq_dst = ((struct ip *)ip)->ip_dst;
#ifdef IPDIVERT
                fp->ipq_divert = 0;
#endif
                q = (struct ipasfrag *)fp;
                goto insert;
        }
 
        /*
         * Find a segment which begins after this one does.
         */
        for (q = fp->ipq_next; q != (struct ipasfrag *)fp; q = q->ipf_next)
                if (q->ip_off > ip->ip_off)
                        break;
 
        /*
         * If there is a preceding segment, it may provide some of
         * our data already.  If so, drop the data from the incoming
         * segment.  If it provides all of our data, drop us.
         */
        if (q->ipf_prev != (struct ipasfrag *)fp) {
                i = q->ipf_prev->ip_off + q->ipf_prev->ip_len - ip->ip_off;
                if (i > 0) {
                        if (i >= ip->ip_len)
                                goto dropfrag;
                        m_adj(dtom(ip), i);
                        ip->ip_off += i;
                        ip->ip_len -= i;
                }
        }
 
        /*
         * While we overlap succeeding segments trim them or,
         * if they are completely covered, dequeue them.
         */
        while (q != (struct ipasfrag *)fp && ip->ip_off + ip->ip_len > q->ip_off) {
                struct mbuf *m0;
 
                i = (ip->ip_off + ip->ip_len) - q->ip_off;
                if (i < q->ip_len) {
                        q->ip_len -= i;
                        q->ip_off += i;
                        m_adj(dtom(q), i);
                        break;
                }
                m0 = dtom(q);
                q = q->ipf_next;
                ip_deq(q->ipf_prev);
                m_freem(m0);
        }
 
insert:
 
#ifdef IPDIVERT
        /*
         * Any fragment diverting causes the whole packet to divert
         */
        if (frag_divert_port != 0)
                fp->ipq_divert = frag_divert_port;
        frag_divert_port = 0;
#endif
 
        /*
         * Stick new segment in its place;
         * check for complete reassembly.
         */
        ip_enq(ip, q->ipf_prev);
        next = 0;
        for (q = fp->ipq_next; q != (struct ipasfrag *)fp; q = q->ipf_next) {
                if (q->ip_off != next)
                        return (0);
                next += q->ip_len;
        }
        if (q->ipf_prev->ipf_mff & 1)
                return (0);
 
        /*
         * Reassembly is complete.  Make sure the packet is a sane size.
         */
        if (next + (IP_VHL_HL(((struct ip *)fp->ipq_next)->ip_vhl) << 2)
                                                        > IP_MAXPACKET) {
                ipstat.ips_toolong++;
                ip_freef(fp);
                return (0);
        }
 
        /*
         * Concatenate fragments.
         */
        q = fp->ipq_next;
        m = dtom(q);
        t = m->m_next;
        m->m_next = 0;
        m_cat(m, t);
        q = q->ipf_next;
        while (q != (struct ipasfrag *)fp) {
                t = dtom(q);
                q = q->ipf_next;
                m_cat(m, t);
        }
 
#ifdef IPDIVERT
        /*
         * Record divert port for packet, if any
         */
        frag_divert_port = fp->ipq_divert;
#endif
 
        /*
         * Create header for new ip packet by
         * modifying header of first packet;
         * dequeue and discard fragment reassembly header.
         * Make header visible.
         */
        ip = fp->ipq_next;
        ip->ip_len = next;
        ip->ipf_mff &= ~1;
        ((struct ip *)ip)->ip_src = fp->ipq_src;
        ((struct ip *)ip)->ip_dst = fp->ipq_dst;
        remque(fp);
        nipq--;
        (void) m_free(dtom(fp));
        m = dtom(ip);
        m->m_len += (ip->ip_hl << 2);
        m->m_data -= (ip->ip_hl << 2);
        /* some debugging cruft by sklower, below, will go away soon */
        if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */
                register int plen = 0;
                for (t = m; m; m = m->m_next)
                        plen += m->m_len;
                t->m_pkthdr.len = plen;
        }
        return ((struct ip *)ip);
 
dropfrag:
        ipstat.ips_fragdropped++;
        m_freem(m);
        return (0);
}
 
/*
 * Free a fragment reassembly header and all
 * associated datagrams.
 */
static void
ip_freef(fp)
        struct ipq *fp;
{
        register struct ipasfrag *q, *p;
 
        for (q = fp->ipq_next; q != (struct ipasfrag *)fp; q = p) {
                p = q->ipf_next;
                ip_deq(q);
                m_freem(dtom(q));
        }
        remque(fp);
        (void) m_free(dtom(fp));
        nipq--;
}
 
/*
 * Put an ip fragment on a reassembly chain.
 * Like insque, but pointers in middle of structure.
 */
static void
ip_enq(p, prev)
        register struct ipasfrag *p, *prev;
{
 
        p->ipf_prev = prev;
        p->ipf_next = prev->ipf_next;
        prev->ipf_next->ipf_prev = p;
        prev->ipf_next = p;
}
 
/*
 * To ip_enq as remque is to insque.
 */
static void
ip_deq(p)
        register struct ipasfrag *p;
{
 
        p->ipf_prev->ipf_next = p->ipf_next;
        p->ipf_next->ipf_prev = p->ipf_prev;
}
 
/*
 * IP timer processing;
 * if a timer expires on a reassembly
 * queue, discard it.
 */
void
ip_slowtimo()
{
        register struct ipq *fp;
        int s = splnet();
        int i;
 
        for (i = 0; i < IPREASS_NHASH; i++) {
                fp = ipq[i].next;
                if (fp == 0)
                        continue;
                while (fp != &ipq[i]) {
                        --fp->ipq_ttl;
                        fp = fp->next;
                        if (fp->prev->ipq_ttl == 0) {
                                ipstat.ips_fragtimeout++;
                                ip_freef(fp->prev);
                        }
                }
        }
        splx(s);
}
 
/*
 * Drain off all datagram fragments.
 */
void
ip_drain()
{
        int     i;
 
        for (i = 0; i < IPREASS_NHASH; i++) {
                while (ipq[i].next != &ipq[i]) {
                        ipstat.ips_fragdropped++;
                        ip_freef(ipq[i].next);
                }
        }
        in_rtqdrain();
}
 
/*
 * Do option processing on a datagram,
 * possibly discarding it if bad options are encountered,
 * or forwarding it if source-routed.
 * Returns 1 if packet has been forwarded/freed,
 * 0 if the packet should be processed further.
 */
static int
ip_dooptions(m)
        struct mbuf *m;
{
        register struct ip *ip = mtod(m, struct ip *);
        register u_char *cp;
        register struct ip_timestamp *ipt;
        register struct in_ifaddr *ia;
        int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
        struct in_addr *sin, dst;
        n_time ntime;
 
        dst = ip->ip_dst;
        cp = (u_char *)(ip + 1);
        cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip);
        for (; cnt > 0; cnt -= optlen, cp += optlen) {
                opt = cp[IPOPT_OPTVAL];
                if (opt == IPOPT_EOL)
                        break;
                if (opt == IPOPT_NOP)
                        optlen = 1;
                else {
                        optlen = cp[IPOPT_OLEN];
                        if (optlen <= 0 || optlen > cnt) {
                                code = &cp[IPOPT_OLEN] - (u_char *)ip;
                                goto bad;
                        }
                }
                switch (opt) {
 
                default:
                        break;
 
                /*
                 * Source routing with record.
                 * Find interface with current destination address.
                 * If none on this machine then drop if strictly routed,
                 * or do nothing if loosely routed.
                 * Record interface address and bring up next address
                 * component.  If strictly routed make sure next
                 * address is on directly accessible net.
                 */
                case IPOPT_LSRR:
                case IPOPT_SSRR:
                        if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
                                code = &cp[IPOPT_OFFSET] - (u_char *)ip;
                                goto bad;
                        }
                        ipaddr.sin_addr = ip->ip_dst;
                        ia = (struct in_ifaddr *)
                                ifa_ifwithaddr((struct sockaddr *)&ipaddr);
                        if (ia == 0) {
                                if (opt == IPOPT_SSRR) {
                                        type = ICMP_UNREACH;
                                        code = ICMP_UNREACH_SRCFAIL;
                                        goto bad;
                                }
                                if (!ip_dosourceroute)
                                        goto nosourcerouting;
                                /*
                                 * Loose routing, and not at next destination
                                 * yet; nothing to do except forward.
                                 */
                                break;
                        }
                        off--;                  /* 0 origin */
                        if (off > optlen - sizeof(struct in_addr)) {
                                /*
                                 * End of source route.  Should be for us.
                                 */
                                if (!ip_acceptsourceroute)
                                        goto nosourcerouting;
                                save_rte(cp, ip->ip_src);
                                break;
                        }
 
                        if (!ip_dosourceroute) {
                                char buf[4*sizeof "123"];
 
nosourcerouting:
                                strcpy(buf, inet_ntoa(ip->ip_dst));
                                log(LOG_WARNING,
                                    "attempted source route from %s to %s\n",
                                    inet_ntoa(ip->ip_src), buf);
                                type = ICMP_UNREACH;
                                code = ICMP_UNREACH_SRCFAIL;
                                goto bad;
                        }
 
                        /*
                         * locate outgoing interface
                         */
                        (void)memcpy(&ipaddr.sin_addr, cp + off,
                            sizeof(ipaddr.sin_addr));
 
                        if (opt == IPOPT_SSRR) {
#define INA     struct in_ifaddr *
#define SA      struct sockaddr *
                            if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0)
                                ia = (INA)ifa_ifwithnet((SA)&ipaddr);
                        } else
                                ia = ip_rtaddr(ipaddr.sin_addr);
                        if (ia == 0) {
                                type = ICMP_UNREACH;
                                code = ICMP_UNREACH_SRCFAIL;
                                goto bad;
                        }
                        ip->ip_dst = ipaddr.sin_addr;
                        (void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
                            sizeof(struct in_addr));
                        cp[IPOPT_OFFSET] += sizeof(struct in_addr);
                        /*
                         * Let ip_intr's mcast routing check handle mcast pkts
                         */
                        forward = !IN_MULTICAST(ntohl(ip->ip_dst.s_addr));
                        break;
 
                case IPOPT_RR:
                        if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
                                code = &cp[IPOPT_OFFSET] - (u_char *)ip;
                                goto bad;
                        }
                        /*
                         * If no space remains, ignore.
                         */
                        off--;                  /* 0 origin */
                        if (off > optlen - sizeof(struct in_addr))
                                break;
                        (void)memcpy(&ipaddr.sin_addr, &ip->ip_dst,
                            sizeof(ipaddr.sin_addr));
                        /*
                         * locate outgoing interface; if we're the destination,
                         * use the incoming interface (should be same).
                         */
                        if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 &&
                            (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) {
                                type = ICMP_UNREACH;
                                code = ICMP_UNREACH_HOST;
                                goto bad;
                        }
                        (void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
                            sizeof(struct in_addr));
                        cp[IPOPT_OFFSET] += sizeof(struct in_addr);
                        break;
 
                case IPOPT_TS:
                        code = cp - (u_char *)ip;
                        ipt = (struct ip_timestamp *)cp;
                        if (ipt->ipt_len < 5)
                                goto bad;
                        if (ipt->ipt_ptr > ipt->ipt_len - sizeof (long)) {
                                if (++ipt->ipt_oflw == 0)
                                        goto bad;
                                break;
                        }
                        sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1);
                        switch (ipt->ipt_flg) {
 
                        case IPOPT_TS_TSONLY:
                                break;
 
                        case IPOPT_TS_TSANDADDR:
                                if (ipt->ipt_ptr + sizeof(n_time) +
                                    sizeof(struct in_addr) > ipt->ipt_len)
                                        goto bad;
                                ipaddr.sin_addr = dst;
                                ia = (INA)ifaof_ifpforaddr((SA)&ipaddr,
                                                            m->m_pkthdr.rcvif);
                                if (ia == 0)
                                        continue;
                                (void)memcpy(sin, &IA_SIN(ia)->sin_addr,
                                    sizeof(struct in_addr));
                                ipt->ipt_ptr += sizeof(struct in_addr);
                                break;
 
                        case IPOPT_TS_PRESPEC:
                                if (ipt->ipt_ptr + sizeof(n_time) +
                                    sizeof(struct in_addr) > ipt->ipt_len)
                                        goto bad;
                                (void)memcpy(&ipaddr.sin_addr, sin,
                                    sizeof(struct in_addr));
                                if (ifa_ifwithaddr((SA)&ipaddr) == 0)
                                        continue;
                                ipt->ipt_ptr += sizeof(struct in_addr);
                                break;
 
                        default:
                                goto bad;
                        }
                        ntime = iptime();
                        (void)memcpy(cp + ipt->ipt_ptr - 1, &ntime,
                            sizeof(n_time));
                        ipt->ipt_ptr += sizeof(n_time);
                }
        }
        if (forward && ipforwarding) {
                ip_forward(m, 1);
                return (1);
        }
        return (0);
bad:
        ip->ip_len -= IP_VHL_HL(ip->ip_vhl) << 2;   /* XXX icmp_error adds in hdr length */
        icmp_error(m, type, code, 0, 0);
        ipstat.ips_badoptions++;
        return (1);
}
 
/*
 * Given address of next destination (final or next hop),
 * return internet address info of interface to be used to get there.
 */
static struct in_ifaddr *
ip_rtaddr(dst)
         struct in_addr dst;
{
        register struct sockaddr_in *sin;
 
        sin = (struct sockaddr_in *) &ipforward_rt.ro_dst;
 
        if (ipforward_rt.ro_rt == 0 || dst.s_addr != sin->sin_addr.s_addr) {
                if (ipforward_rt.ro_rt) {
                        RTFREE(ipforward_rt.ro_rt);
                        ipforward_rt.ro_rt = 0;
                }
                sin->sin_family = AF_INET;
                sin->sin_len = sizeof(*sin);
                sin->sin_addr = dst;
 
                rtalloc_ign(&ipforward_rt, RTF_PRCLONING);
        }
        if (ipforward_rt.ro_rt == 0)
                return ((struct in_ifaddr *)0);
        return ((struct in_ifaddr *) ipforward_rt.ro_rt->rt_ifa);
}
 
/*
 * Save incoming source route for use in replies,
 * to be picked up later by ip_srcroute if the receiver is interested.
 */
void
save_rte(option, dst)
        u_char *option;
        struct in_addr dst;
{
        unsigned olen;
 
        olen = option[IPOPT_OLEN];
#ifdef DIAGNOSTIC
        if (ipprintfs)
                printf("save_rte: olen %d\n", olen);
#endif
        if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst)))
                return;
        bcopy(option, ip_srcrt.srcopt, olen);
        ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
        ip_srcrt.dst = dst;
}
 
/*
 * Retrieve incoming source route for use in replies,
 * in the same form used by setsockopt.
 * The first hop is placed before the options, will be removed later.
 */
struct mbuf *
ip_srcroute()
{
        register struct in_addr *p, *q;
        register struct mbuf *m;
 
        if (ip_nhops == 0)
                return ((struct mbuf *)0);
        m = m_get(M_DONTWAIT, MT_SOOPTS);
        if (m == 0)
                return ((struct mbuf *)0);
 
#define OPTSIZ  (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt))
 
        /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */
        m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) +
            OPTSIZ;
#ifdef DIAGNOSTIC
        if (ipprintfs)
                printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len);
#endif
 
        /*
         * First save first hop for return route
         */
        p = &ip_srcrt.route[ip_nhops - 1];
        *(mtod(m, struct in_addr *)) = *p--;
#ifdef DIAGNOSTIC
        if (ipprintfs)
                printf(" hops %lx", ntohl(mtod(m, struct in_addr *)->s_addr));
#endif
 
        /*
         * Copy option fields and padding (nop) to mbuf.
         */
        ip_srcrt.nop = IPOPT_NOP;
        ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF;
        (void)memcpy(mtod(m, caddr_t) + sizeof(struct in_addr),
            &ip_srcrt.nop, OPTSIZ);
        q = (struct in_addr *)(mtod(m, caddr_t) +
            sizeof(struct in_addr) + OPTSIZ);
#undef OPTSIZ
        /*
         * Record return path as an IP source route,
         * reversing the path (pointers are now aligned).
         */
        while (p >= ip_srcrt.route) {
#ifdef DIAGNOSTIC
                if (ipprintfs)
                        printf(" %lx", ntohl(q->s_addr));
#endif
                *q++ = *p--;
        }
        /*
         * Last hop goes to final destination.
         */
        *q = ip_srcrt.dst;
#ifdef DIAGNOSTIC
        if (ipprintfs)
                printf(" %lx\n", ntohl(q->s_addr));
#endif
        return (m);
}
 
/*
 * Strip out IP options, at higher
 * level protocol in the kernel.
 * Second argument is buffer to which options
 * will be moved, and return value is their length.
 * XXX should be deleted; last arg currently ignored.
 */
void
ip_stripoptions(m, mopt)
        register struct mbuf *m;
        struct mbuf *mopt;
{
        register int i;
        struct ip *ip = mtod(m, struct ip *);
        register caddr_t opts;
        int olen;
 
        olen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip);
        opts = (caddr_t)(ip + 1);
        i = m->m_len - (sizeof (struct ip) + olen);
        bcopy(opts + olen, opts, (unsigned)i);
        m->m_len -= olen;
        if (m->m_flags & M_PKTHDR)
                m->m_pkthdr.len -= olen;
        ip->ip_vhl = IP_MAKE_VHL(IPVERSION, sizeof(struct ip) >> 2);
}
 
u_char inetctlerrmap[PRC_NCMDS] = {
        0,               0,               0,               0,
        0,               EMSGSIZE,       EHOSTDOWN,      EHOSTUNREACH,
        EHOSTUNREACH,   EHOSTUNREACH,   ECONNREFUSED,   ECONNREFUSED,
        EMSGSIZE,       EHOSTUNREACH,   0,               0,
        0,               0,               0,               0,
        ENOPROTOOPT
};
 
/*
 * Forward a packet.  If some error occurs return the sender
 * an icmp packet.  Note we can't always generate a meaningful
 * icmp message because icmp doesn't have a large enough repertoire
 * of codes and types.
 *
 * If not forwarding, just drop the packet.  This could be confusing
 * if ipforwarding was zero but some routing protocol was advancing
 * us as a gateway to somewhere.  However, we must let the routing
 * protocol deal with that.
 *
 * The srcrt parameter indicates whether the packet is being forwarded
 * via a source route.
 */
static void
ip_forward(m, srcrt)
        struct mbuf *m;
        int srcrt;
{
        register struct ip *ip = mtod(m, struct ip *);
        register struct sockaddr_in *sin;
        register struct rtentry *rt;
        int error, type = 0, code = 0;
        struct mbuf *mcopy;
        n_long dest;
        struct ifnet *destifp;
 
        dest = 0;
#ifdef DIAGNOSTIC
        if (ipprintfs)
                printf("forward: src %lx dst %lx ttl %x\n",
                        ip->ip_src.s_addr, ip->ip_dst.s_addr, ip->ip_ttl);
#endif
 
 
        if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) {
                ipstat.ips_cantforward++;
                m_freem(m);
                return;
        }
        HTONS(ip->ip_id);
        if (ip->ip_ttl <= IPTTLDEC) {
                icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0);
                return;
        }
        ip->ip_ttl -= IPTTLDEC;
 
        sin = (struct sockaddr_in *)&ipforward_rt.ro_dst;
        if ((rt = ipforward_rt.ro_rt) == 0 ||
            ip->ip_dst.s_addr != sin->sin_addr.s_addr) {
                if (ipforward_rt.ro_rt) {
                        RTFREE(ipforward_rt.ro_rt);
                        ipforward_rt.ro_rt = 0;
                }
                sin->sin_family = AF_INET;
                sin->sin_len = sizeof(*sin);
                sin->sin_addr = ip->ip_dst;
 
                rtalloc_ign(&ipforward_rt, RTF_PRCLONING);
                if (ipforward_rt.ro_rt == 0) {
                        icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0);
                        return;
                }
                rt = ipforward_rt.ro_rt;
        }
 
        /*
         * Save at most 64 bytes of the packet in case
         * we need to generate an ICMP message to the src.
         */
        mcopy = m_copy(m, 0, imin((int)ip->ip_len, 64));
 
        /*
         * If forwarding packet using same interface that it came in on,
         * perhaps should send a redirect to sender to shortcut a hop.
         * Only send redirect if source is sending directly to us,
         * and if packet was not source routed (or has any options).
         * Also, don't send redirect if forwarding using a default route
         * or a route modified by a redirect.
         */
#define satosin(sa)     ((struct sockaddr_in *)(sa))
        if (rt->rt_ifp == m->m_pkthdr.rcvif &&
            (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
            satosin(rt_key(rt))->sin_addr.s_addr != 0 &&
            ipsendredirects && !srcrt) {
#define RTA(rt) ((struct in_ifaddr *)(rt->rt_ifa))
                u_long src = ntohl(ip->ip_src.s_addr);
 
                if (RTA(rt) &&
                    (src & RTA(rt)->ia_subnetmask) == RTA(rt)->ia_subnet) {
                    if (rt->rt_flags & RTF_GATEWAY)
                        dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
                    else
                        dest = ip->ip_dst.s_addr;
                    /* Router requirements says to only send host redirects */
                    type = ICMP_REDIRECT;
                    code = ICMP_REDIRECT_HOST;
#ifdef DIAGNOSTIC
                    if (ipprintfs)
                        printf("redirect (%d) to %lx\n", code, (u_long)dest);
#endif
                }
        }
 
        error = ip_output(m, (struct mbuf *)0, &ipforward_rt,
                          IP_FORWARDING, 0);
        if (error)
                ipstat.ips_cantforward++;
        else {
                ipstat.ips_forward++;
                if (type)
                        ipstat.ips_redirectsent++;
                else {
                        if (mcopy)
                                m_freem(mcopy);
                        return;
                }
        }
        if (mcopy == NULL)
                return;
        destifp = NULL;
 
        switch (error) {
 
        case 0:                          /* forwarded, but need redirect */
                /* type, code set above */
                break;
 
        case ENETUNREACH:               /* shouldn't happen, checked above */
        case EHOSTUNREACH:
        case ENETDOWN:
        case EHOSTDOWN:
        default:
                type = ICMP_UNREACH;
                code = ICMP_UNREACH_HOST;
                break;
 
        case EMSGSIZE:
                type = ICMP_UNREACH;
                code = ICMP_UNREACH_NEEDFRAG;
                if (ipforward_rt.ro_rt)
                        destifp = ipforward_rt.ro_rt->rt_ifp;
                ipstat.ips_cantfrag++;
                break;
 
        case ENOBUFS:
                type = ICMP_SOURCEQUENCH;
                code = 0;
                break;
        }
        icmp_error(mcopy, type, code, dest, destifp);
}
 
void
ip_savecontrol(inp, mp, ip, m)
        register struct inpcb *inp;
        register struct mbuf **mp;
        register struct ip *ip;
        register struct mbuf *m;
{
        if (inp->inp_socket->so_options & SO_TIMESTAMP) {
                struct timeval tv;
 
                microtime(&tv);
                *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
                        SCM_TIMESTAMP, SOL_SOCKET);
                if (*mp)
                        mp = &(*mp)->m_next;
        }
        if (inp->inp_flags & INP_RECVDSTADDR) {
                *mp = sbcreatecontrol((caddr_t) &ip->ip_dst,
                    sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
                if (*mp)
                        mp = &(*mp)->m_next;
        }
#ifdef notyet
        /* XXX
         * Moving these out of udp_input() made them even more broken
         * than they already were.
         */
        /* options were tossed already */
        if (inp->inp_flags & INP_RECVOPTS) {
                *mp = sbcreatecontrol((caddr_t) opts_deleted_above,
                    sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
                if (*mp)
                        mp = &(*mp)->m_next;
        }
        /* ip_srcroute doesn't do what we want here, need to fix */
        if (inp->inp_flags & INP_RECVRETOPTS) {
                *mp = sbcreatecontrol((caddr_t) ip_srcroute(),
                    sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
                if (*mp)
                        mp = &(*mp)->m_next;
        }
#endif
        if (inp->inp_flags & INP_RECVIF) {
                struct sockaddr_dl sdl;
 
                sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]);
                sdl.sdl_family = AF_LINK;
                sdl.sdl_index = m->m_pkthdr.rcvif ?
                        m->m_pkthdr.rcvif->if_index : 0;
                sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0;
                *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len,
                        IP_RECVIF, IPPROTO_IP);
                if (*mp)
                        mp = &(*mp)->m_next;
        }
}
 
int
ip_rsvp_init(struct socket *so)
{
        if (so->so_type != SOCK_RAW ||
            so->so_proto->pr_protocol != IPPROTO_RSVP)
          return EOPNOTSUPP;
 
        if (ip_rsvpd != NULL)
          return EADDRINUSE;
 
        ip_rsvpd = so;
        /*
         * This may seem silly, but we need to be sure we don't over-increment
         * the RSVP counter, in case something slips up.
         */
        if (!ip_rsvp_on) {
                ip_rsvp_on = 1;
                rsvp_on++;
        }
 
        return 0;
}
 
int
ip_rsvp_done(void)
{
        ip_rsvpd = NULL;
        /*
         * This may seem silly, but we need to be sure we don't over-decrement
         * the RSVP counter, in case something slips up.
         */
        if (ip_rsvp_on) {
                ip_rsvp_on = 0;
                rsvp_on--;
        }
        return 0;
}
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[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [libnetworking/] [netinet/] [ip_input.c] - Blame information for rev 773

Line No.	Rev	Author	Line
1	30	unneback	`/*`
2			`* Copyright (c) 1982, 1986, 1988, 1993`
3			`* The Regents of the University of California. All rights reserved.`
4			`*`
5			`* Redistribution and use in source and binary forms, with or without`
6			`* modification, are permitted provided that the following conditions`
7			`* are met:`
8			`* 1. Redistributions of source code must retain the above copyright`
9			`* notice, this list of conditions and the following disclaimer.`
10			`* 2. Redistributions in binary form must reproduce the above copyright`
11			`* notice, this list of conditions and the following disclaimer in the`
12			`* documentation and/or other materials provided with the distribution.`
13			`* 3. All advertising materials mentioning features or use of this software`
14			`* must display the following acknowledgement:`
15			`* This product includes software developed by the University of`
16			`* California, Berkeley and its contributors.`
17			`* 4. Neither the name of the University nor the names of its contributors`
18			`* may be used to endorse or promote products derived from this software`
19			`* without specific prior written permission.`
20			`*`
21			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22			`* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE`
23			`* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE`
24			`* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE`
25			`* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL`
26			`* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS`
27			`* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)`
28			`* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT`
29			`* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY`
30			`* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF`
31			`* SUCH DAMAGE.`
32			`*`
33			`* @(#)ip_input.c 8.2 (Berkeley) 1/4/94`
34			`* $Id: ip_input.c,v 1.2 2001-09-27 12:01:55 chris Exp $`
35			`* $ANA: ip_input.c,v 1.5 1996/09/18 14:34:59 wollman Exp $`
36			`*/`
37
38			`#define _IP_VHL`
39
40			`#include "opt_ipfw.h"`