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-rw-r--r--sys/netinet/ip_output.c614
1 files changed, 614 insertions, 0 deletions
diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c
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index 000000000000..ec5a5dd4527d
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+++ b/sys/netinet/ip_output.c
@@ -0,0 +1,614 @@
+/*
+ * Copyright (c) 1982, 1986, 1988, 1990 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.
+ *
+ * from: @(#)ip_output.c 7.23 (Berkeley) 11/12/90
+ * $Id: ip_output.c,v 1.3 1993/10/19 09:14:15 davidg Exp $
+ */
+
+#include "param.h"
+#include "malloc.h"
+#include "mbuf.h"
+#include "errno.h"
+#include "protosw.h"
+#include "socket.h"
+#include "socketvar.h"
+
+#include "../net/if.h"
+#include "../net/route.h"
+
+#include "in.h"
+#include "in_systm.h"
+#include "ip.h"
+#include "in_pcb.h"
+#include "in_var.h"
+#include "ip_var.h"
+
+#ifdef vax
+#include "machine/mtpr.h"
+#endif
+
+struct mbuf *ip_insertoptions();
+
+/*
+ * IP output. The packet in mbuf chain m contains a skeletal IP
+ * header (with len, off, ttl, proto, tos, src, dst).
+ * The mbuf chain containing the packet will be freed.
+ * The mbuf opt, if present, will not be freed.
+ */
+ip_output(m0, opt, ro, flags)
+ struct mbuf *m0;
+ struct mbuf *opt;
+ struct route *ro;
+ int flags;
+{
+ register struct ip *ip, *mhip;
+ register struct ifnet *ifp;
+ register struct mbuf *m = m0;
+ register int hlen = sizeof (struct ip);
+ int len, off, error = 0;
+ struct route iproute;
+ struct sockaddr_in *dst;
+ struct in_ifaddr *ia;
+
+#ifdef DIAGNOSTIC
+ if ((m->m_flags & M_PKTHDR) == 0)
+ panic("ip_output no HDR");
+#endif
+ if (opt) {
+ m = ip_insertoptions(m, opt, &len);
+ hlen = len;
+ }
+ ip = mtod(m, struct ip *);
+ /*
+ * Fill in IP header.
+ */
+ if ((flags & IP_FORWARDING) == 0) {
+ ip->ip_v = IPVERSION;
+ ip->ip_off &= IP_DF;
+ ip->ip_id = htons(ip_id++);
+ ip->ip_hl = hlen >> 2;
+ } else {
+ hlen = ip->ip_hl << 2;
+ ipstat.ips_localout++;
+ }
+ /*
+ * Route packet.
+ */
+ if (ro == 0) {
+ ro = &iproute;
+ bzero((caddr_t)ro, sizeof (*ro));
+ }
+ dst = (struct sockaddr_in *)&ro->ro_dst;
+ /*
+ * If there is a cached route,
+ * check that it is to the same destination
+ * and is still up. If not, free it and try again.
+ */
+ if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
+ dst->sin_addr.s_addr != ip->ip_dst.s_addr)) {
+ RTFREE(ro->ro_rt);
+ ro->ro_rt = (struct rtentry *)0;
+ }
+ if (ro->ro_rt == 0) {
+ dst->sin_family = AF_INET;
+ dst->sin_len = sizeof(*dst);
+ dst->sin_addr = ip->ip_dst;
+ }
+ /*
+ * If routing to interface only,
+ * short circuit routing lookup.
+ */
+ if (flags & IP_ROUTETOIF) {
+
+ ia = (struct in_ifaddr *)ifa_ifwithdstaddr((struct sockaddr *)dst);
+ if (ia == 0)
+ ia = in_iaonnetof(in_netof(ip->ip_dst));
+ if (ia == 0) {
+ error = ENETUNREACH;
+ goto bad;
+ }
+ ifp = ia->ia_ifp;
+ } else {
+ if (ro->ro_rt == 0)
+ rtalloc(ro);
+ if (ro->ro_rt == 0) {
+ error = EHOSTUNREACH;
+ goto bad;
+ }
+ ia = (struct in_ifaddr *)ro->ro_rt->rt_ifa;
+ ifp = ro->ro_rt->rt_ifp;
+ ro->ro_rt->rt_use++;
+ if (ro->ro_rt->rt_flags & RTF_GATEWAY)
+ dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
+ }
+#ifndef notdef
+ /*
+ * If source address not specified yet, use address
+ * of outgoing interface.
+ */
+ if (ip->ip_src.s_addr == INADDR_ANY)
+ ip->ip_src = IA_SIN(ia)->sin_addr;
+#endif
+
+ /*
+ * Verify that we have any chance at all of being able to queue
+ * the packet or packet fragments
+ */
+ if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >=
+ ifp->if_snd.ifq_maxlen) {
+ error = ENOBUFS;
+ goto bad;
+ }
+
+ /*
+ * Look for broadcast address and
+ * and verify user is allowed to send
+ * such a packet.
+ */
+ if (in_broadcast(dst->sin_addr)) {
+ if ((ifp->if_flags & IFF_BROADCAST) == 0) {
+ error = EADDRNOTAVAIL;
+ goto bad;
+ }
+ if ((flags & IP_ALLOWBROADCAST) == 0) {
+ error = EACCES;
+ goto bad;
+ }
+ /* don't allow broadcast messages to be fragmented */
+ if ((u_short)ip->ip_len > ifp->if_mtu) {
+ error = EMSGSIZE;
+ goto bad;
+ }
+ m->m_flags |= M_BCAST;
+ }
+
+ /*
+ * If small enough for interface, can just send directly.
+ */
+ if ((u_short)ip->ip_len <= ifp->if_mtu) {
+ ip->ip_len = htons((u_short)ip->ip_len);
+ ip->ip_off = htons((u_short)ip->ip_off);
+ ip->ip_sum = 0;
+ ip->ip_sum = in_cksum(m, hlen);
+ error = (*ifp->if_output)(ifp, m,
+ (struct sockaddr *)dst, ro->ro_rt);
+ goto done;
+ }
+ ipstat.ips_fragmented++;
+ /*
+ * Too large for interface; fragment if possible.
+ * Must be able to put at least 8 bytes per fragment.
+ */
+ if (ip->ip_off & IP_DF) {
+ error = EMSGSIZE;
+ goto bad;
+ }
+ len = (ifp->if_mtu - hlen) &~ 7;
+ if (len < 8) {
+ error = EMSGSIZE;
+ goto bad;
+ }
+
+ {
+ int mhlen, firstlen = len;
+ struct mbuf **mnext = &m->m_nextpkt;
+
+ /*
+ * Loop through length of segment after first fragment,
+ * make new header and copy data of each part and link onto chain.
+ */
+ m0 = m;
+ mhlen = sizeof (struct ip);
+ for (off = hlen + len; off < (u_short)ip->ip_len; off += len) {
+ MGETHDR(m, M_DONTWAIT, MT_HEADER);
+ if (m == 0) {
+ error = ENOBUFS;
+ goto sendorfree;
+ }
+ m->m_data += max_linkhdr;
+ mhip = mtod(m, struct ip *);
+ *mhip = *ip;
+ if (hlen > sizeof (struct ip)) {
+ mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
+ mhip->ip_hl = mhlen >> 2;
+ }
+ m->m_len = mhlen;
+ mhip->ip_off = ((off - hlen) >> 3) + (ip->ip_off & ~IP_MF);
+ if (ip->ip_off & IP_MF)
+ mhip->ip_off |= IP_MF;
+ if (off + len >= (u_short)ip->ip_len)
+ len = (u_short)ip->ip_len - off;
+ else
+ mhip->ip_off |= IP_MF;
+ mhip->ip_len = htons((u_short)(len + mhlen));
+ m->m_next = m_copy(m0, off, len);
+ if (m->m_next == 0) {
+ error = ENOBUFS; /* ??? */
+ goto sendorfree;
+ }
+ m->m_pkthdr.len = mhlen + len;
+ m->m_pkthdr.rcvif = (struct ifnet *)0;
+ mhip->ip_off = htons((u_short)mhip->ip_off);
+ mhip->ip_sum = 0;
+ mhip->ip_sum = in_cksum(m, mhlen);
+ *mnext = m;
+ mnext = &m->m_nextpkt;
+ ipstat.ips_ofragments++;
+ }
+ /*
+ * Update first fragment by trimming what's been copied out
+ * and updating header, then send each fragment (in order).
+ */
+ m = m0;
+ m_adj(m, hlen + firstlen - (u_short)ip->ip_len);
+ m->m_pkthdr.len = hlen + firstlen;
+ ip->ip_len = htons((u_short)m->m_pkthdr.len);
+ ip->ip_off = htons((u_short)(ip->ip_off | IP_MF));
+ ip->ip_sum = 0;
+ ip->ip_sum = in_cksum(m, hlen);
+sendorfree:
+ for (m = m0; m; m = m0) {
+ m0 = m->m_nextpkt;
+ m->m_nextpkt = 0;
+ if (error == 0)
+ error = (*ifp->if_output)(ifp, m,
+ (struct sockaddr *)dst, ro->ro_rt);
+ else
+ m_freem(m);
+ }
+ }
+done:
+ if (ro == &iproute && (flags & IP_ROUTETOIF) == 0 && ro->ro_rt)
+ RTFREE(ro->ro_rt);
+ return (error);
+bad:
+ m_freem(m0);
+ goto done;
+}
+
+/*
+ * Insert IP options into preformed packet.
+ * Adjust IP destination as required for IP source routing,
+ * as indicated by a non-zero in_addr at the start of the options.
+ */
+struct mbuf *
+ip_insertoptions(m, opt, phlen)
+ register struct mbuf *m;
+ struct mbuf *opt;
+ int *phlen;
+{
+ register struct ipoption *p = mtod(opt, struct ipoption *);
+ struct mbuf *n;
+ register struct ip *ip = mtod(m, struct ip *);
+ unsigned optlen;
+
+ optlen = opt->m_len - sizeof(p->ipopt_dst);
+ if (optlen + (u_short)ip->ip_len > IP_MAXPACKET)
+ return (m); /* XXX should fail */
+ if (p->ipopt_dst.s_addr)
+ ip->ip_dst = p->ipopt_dst;
+ if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
+ MGETHDR(n, M_DONTWAIT, MT_HEADER);
+ if (n == 0)
+ return (m);
+ n->m_pkthdr.len = m->m_pkthdr.len + optlen;
+ m->m_len -= sizeof(struct ip);
+ m->m_data += sizeof(struct ip);
+ n->m_next = m;
+ m = n;
+ m->m_len = optlen + sizeof(struct ip);
+ m->m_data += max_linkhdr;
+ bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
+ } else {
+ m->m_data -= optlen;
+ m->m_len += optlen;
+ m->m_pkthdr.len += optlen;
+ ovbcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
+ }
+ ip = mtod(m, struct ip *);
+ bcopy((caddr_t)p->ipopt_list, (caddr_t)(ip + 1), (unsigned)optlen);
+ *phlen = sizeof(struct ip) + optlen;
+ ip->ip_len += optlen;
+ return (m);
+}
+
+/*
+ * Copy options from ip to jp,
+ * omitting those not copied during fragmentation.
+ */
+ip_optcopy(ip, jp)
+ struct ip *ip, *jp;
+{
+ register u_char *cp, *dp;
+ int opt, optlen, cnt;
+
+ cp = (u_char *)(ip + 1);
+ dp = (u_char *)(jp + 1);
+ cnt = (ip->ip_hl << 2) - sizeof (struct ip);
+ for (; cnt > 0; cnt -= optlen, cp += optlen) {
+ opt = cp[0];
+ if (opt == IPOPT_EOL)
+ break;
+ if (opt == IPOPT_NOP)
+ optlen = 1;
+ else
+ optlen = cp[IPOPT_OLEN];
+ /* bogus lengths should have been caught by ip_dooptions */
+ if (optlen > cnt)
+ optlen = cnt;
+ if (IPOPT_COPIED(opt)) {
+ bcopy((caddr_t)cp, (caddr_t)dp, (unsigned)optlen);
+ dp += optlen;
+ }
+ }
+ for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
+ *dp++ = IPOPT_EOL;
+ return (optlen);
+}
+
+/*
+ * IP socket option processing.
+ */
+ip_ctloutput(op, so, level, optname, mp)
+ int op;
+ struct socket *so;
+ int level, optname;
+ struct mbuf **mp;
+{
+ register struct inpcb *inp = sotoinpcb(so);
+ register struct mbuf *m = *mp;
+ register int optval;
+ int error = 0;
+
+ if (level != IPPROTO_IP)
+ error = EINVAL;
+ else switch (op) {
+
+ case PRCO_SETOPT:
+ switch (optname) {
+ case IP_OPTIONS:
+#ifdef notyet
+ case IP_RETOPTS:
+ return (ip_pcbopts(optname, &inp->inp_options, m));
+#else
+ return (ip_pcbopts(&inp->inp_options, m));
+#endif
+
+ case IP_TOS:
+ case IP_TTL:
+ case IP_RECVOPTS:
+ case IP_RECVRETOPTS:
+ case IP_RECVDSTADDR:
+ if (m->m_len != sizeof(int))
+ error = EINVAL;
+ else {
+ optval = *mtod(m, int *);
+ switch (optname) {
+
+ case IP_TOS:
+ inp->inp_ip.ip_tos = optval;
+ break;
+
+ case IP_TTL:
+ inp->inp_ip.ip_ttl = optval;
+ break;
+#define OPTSET(bit) \
+ if (optval) \
+ inp->inp_flags |= bit; \
+ else \
+ inp->inp_flags &= ~bit;
+
+ case IP_RECVOPTS:
+ OPTSET(INP_RECVOPTS);
+ break;
+
+ case IP_RECVRETOPTS:
+ OPTSET(INP_RECVRETOPTS);
+ break;
+
+ case IP_RECVDSTADDR:
+ OPTSET(INP_RECVDSTADDR);
+ break;
+ }
+ }
+ break;
+#undef OPTSET
+
+ default:
+ error = EINVAL;
+ break;
+ }
+ if (m)
+ (void)m_free(m);
+ break;
+
+ case PRCO_GETOPT:
+ switch (optname) {
+ case IP_OPTIONS:
+ case IP_RETOPTS:
+ *mp = m = m_get(M_WAIT, MT_SOOPTS);
+ if (inp->inp_options) {
+ m->m_len = inp->inp_options->m_len;
+ bcopy(mtod(inp->inp_options, caddr_t),
+ mtod(m, caddr_t), (unsigned)m->m_len);
+ } else
+ m->m_len = 0;
+ break;
+
+ case IP_TOS:
+ case IP_TTL:
+ case IP_RECVOPTS:
+ case IP_RECVRETOPTS:
+ case IP_RECVDSTADDR:
+ *mp = m = m_get(M_WAIT, MT_SOOPTS);
+ m->m_len = sizeof(int);
+ switch (optname) {
+
+ case IP_TOS:
+ optval = inp->inp_ip.ip_tos;
+ break;
+
+ case IP_TTL:
+ optval = inp->inp_ip.ip_ttl;
+ break;
+
+#define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
+
+ case IP_RECVOPTS:
+ optval = OPTBIT(INP_RECVOPTS);
+ break;
+
+ case IP_RECVRETOPTS:
+ optval = OPTBIT(INP_RECVRETOPTS);
+ break;
+
+ case IP_RECVDSTADDR:
+ optval = OPTBIT(INP_RECVDSTADDR);
+ break;
+ }
+ *mtod(m, int *) = optval;
+ break;
+
+ default:
+ error = EINVAL;
+ break;
+ }
+ break;
+ }
+ return (error);
+}
+
+/*
+ * Set up IP options in pcb for insertion in output packets.
+ * Store in mbuf with pointer in pcbopt, adding pseudo-option
+ * with destination address if source routed.
+ */
+#ifdef notyet
+ip_pcbopts(optname, pcbopt, m)
+ int optname;
+#else
+ip_pcbopts(pcbopt, m)
+#endif
+ struct mbuf **pcbopt;
+ register struct mbuf *m;
+{
+ register cnt, optlen;
+ register u_char *cp;
+ u_char opt;
+
+ /* turn off any old options */
+ if (*pcbopt)
+ (void)m_free(*pcbopt);
+ *pcbopt = 0;
+ if (m == (struct mbuf *)0 || m->m_len == 0) {
+ /*
+ * Only turning off any previous options.
+ */
+ if (m)
+ (void)m_free(m);
+ return (0);
+ }
+
+#ifndef vax
+ if (m->m_len % sizeof(long))
+ goto bad;
+#endif
+ /*
+ * IP first-hop destination address will be stored before
+ * actual options; move other options back
+ * and clear it when none present.
+ */
+ if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
+ goto bad;
+ cnt = m->m_len;
+ m->m_len += sizeof(struct in_addr);
+ cp = mtod(m, u_char *) + sizeof(struct in_addr);
+ ovbcopy(mtod(m, caddr_t), (caddr_t)cp, (unsigned)cnt);
+ bzero(mtod(m, caddr_t), sizeof(struct in_addr));
+
+ 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 <= IPOPT_OLEN || optlen > cnt)
+ goto bad;
+ }
+ switch (opt) {
+
+ default:
+ break;
+
+ case IPOPT_LSRR:
+ case IPOPT_SSRR:
+ /*
+ * user process specifies route as:
+ * ->A->B->C->D
+ * D must be our final destination (but we can't
+ * check that since we may not have connected yet).
+ * A is first hop destination, which doesn't appear in
+ * actual IP option, but is stored before the options.
+ */
+ if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
+ goto bad;
+ m->m_len -= sizeof(struct in_addr);
+ cnt -= sizeof(struct in_addr);
+ optlen -= sizeof(struct in_addr);
+ cp[IPOPT_OLEN] = optlen;
+ /*
+ * Move first hop before start of options.
+ */
+ bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
+ sizeof(struct in_addr));
+ /*
+ * Then copy rest of options back
+ * to close up the deleted entry.
+ */
+ ovbcopy((caddr_t)(&cp[IPOPT_OFFSET+1] +
+ sizeof(struct in_addr)),
+ (caddr_t)&cp[IPOPT_OFFSET+1],
+ (unsigned)cnt + sizeof(struct in_addr));
+ break;
+ }
+ }
+ if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
+ goto bad;
+ *pcbopt = m;
+ return (0);
+
+bad:
+ (void)m_free(m);
+ return (EINVAL);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2026-03-28 05:26:05 +0000