-/* ip_output.c 6.2 83/10/22 */
+/*
+ * Copyright (c) 1982, 1986 Regents of the University of California.
+ * All rights reserved. The Berkeley software License Agreement
+ * specifies the terms and conditions for redistribution.
+ *
+ * @(#)ip_output.c 7.6 (Berkeley) %G%
+ */
-#include "../h/param.h"
-#include "../h/mbuf.h"
-#include "../h/errno.h"
-#include "../h/socket.h"
-#include "../h/socketvar.h"
+#include "param.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 "../netinet/in.h"
-#include "../netinet/in_systm.h"
-#include "../netinet/ip.h"
-#include "../netinet/ip_var.h"
+#include "in.h"
+#include "in_pcb.h"
+#include "in_systm.h"
+#include "in_var.h"
+#include "ip.h"
+#include "ip_var.h"
#ifdef vax
-#include "../vax/mtpr.h"
+#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(m, opt, ro, flags)
struct mbuf *m;
struct mbuf *opt;
struct route *ro;
int flags;
{
- register struct ip *ip = mtod(m, struct ip *);
+ register struct ip *ip;
register struct ifnet *ifp;
int len, hlen = sizeof (struct ip), off, error = 0;
struct route iproute;
- struct sockaddr *dst;
+ struct sockaddr_in *dst;
- if (opt) /* XXX */
- (void) m_free(opt); /* XXX */
+ if (opt)
+ m = ip_insertoptions(m, opt, &hlen);
+ ip = mtod(m, struct ip *);
/*
* Fill in IP header.
*/
- ip->ip_hl = hlen >> 2;
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;
/*
* Route packet.
ro = &iproute;
bzero((caddr_t)ro, sizeof (*ro));
}
- dst = &ro->ro_dst;
+ 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) {
- ro->ro_dst.sa_family = AF_INET;
- ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = ip->ip_dst;
- /*
- * If routing to interface only,
- * short circuit routing lookup.
- */
- if (flags & IP_ROUTETOIF) {
- ifp = if_ifonnetof(in_netof(ip->ip_dst));
- if (ifp == 0) {
+ dst->sin_family = AF_INET;
+ dst->sin_addr = ip->ip_dst;
+ }
+ /*
+ * If routing to interface only,
+ * short circuit routing lookup.
+ */
+ if (flags & IP_ROUTETOIF) {
+ struct in_ifaddr *ia;
+
+ ia = (struct in_ifaddr *)ifa_ifwithdstaddr(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 || (ifp = ro->ro_rt->rt_ifp) == 0) {
+ if (in_localaddr(ip->ip_dst))
+ error = EHOSTUNREACH;
+ else
error = ENETUNREACH;
- goto bad;
- }
- goto gotif;
+ goto bad;
}
- rtalloc(ro);
- }
- if (ro->ro_rt == 0 || (ifp = ro->ro_rt->rt_ifp) == 0) {
- error = ENETUNREACH;
- goto bad;
+ ro->ro_rt->rt_use++;
+ if (ro->ro_rt->rt_flags & RTF_GATEWAY)
+ dst = (struct sockaddr_in *)&ro->ro_rt->rt_gateway;
}
- ro->ro_rt->rt_use++;
- if (ro->ro_rt->rt_flags & (RTF_GATEWAY|RTF_HOST))
- dst = &ro->ro_rt->rt_gateway;
-gotif:
#ifndef notdef
/*
* If source address not specified yet, use address
* of outgoing interface.
*/
- if (in_lnaof(ip->ip_src) == INADDR_ANY)
- ip->ip_src.s_addr =
- ((struct sockaddr_in *)&ifp->if_addr)->sin_addr.s_addr;
-#endif
+ if (ip->ip_src.s_addr == INADDR_ANY) {
+ register struct in_ifaddr *ia;
+ for (ia = in_ifaddr; ia; ia = ia->ia_next)
+ if (ia->ia_ifp == ifp) {
+ ip->ip_src = IA_SIN(ia)->sin_addr;
+ break;
+ }
+ }
+#endif
/*
* Look for broadcast address and
* and verify user is allowed to send
* such a packet.
*/
- if (in_lnaof(((struct sockaddr_in *)dst)->sin_addr) == INADDR_ANY) {
+ if (in_broadcast(dst->sin_addr)) {
if ((ifp->if_flags & IFF_BROADCAST) == 0) {
error = EADDRNOTAVAIL;
goto bad;
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, dst);
+ error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst);
goto done;
}
mh->m_len = sizeof (struct ip) + olen;
} else
mh->m_len = sizeof (struct ip);
- mhip->ip_off = off >> 3;
+ mhip->ip_off = (off >> 3) + (ip->ip_off & ~IP_MF);
+ if (ip->ip_off & IP_MF)
+ mhip->ip_off |= IP_MF;
if (off + len >= ip->ip_len-hlen)
len = mhip->ip_len = ip->ip_len - hlen - off;
else {
mhip->ip_off = htons((u_short)mhip->ip_off);
mhip->ip_sum = 0;
mhip->ip_sum = in_cksum(mh, hlen);
- if (error = (*ifp->if_output)(ifp, mh, dst))
+ if (error = (*ifp->if_output)(ifp, mh, (struct sockaddr *)dst))
break;
}
- m_freem(m);
- goto done;
-
bad:
m_freem(m);
done:
return (error);
}
+/*
+ * 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 (p->ipopt_dst.s_addr)
+ ip->ip_dst = p->ipopt_dst;
+ if (m->m_off >= MMAXOFF || MMINOFF + optlen > m->m_off) {
+ MGET(n, M_DONTWAIT, MT_HEADER);
+ if (n == 0)
+ return (m);
+ m->m_len -= sizeof(struct ip);
+ m->m_off += sizeof(struct ip);
+ n->m_next = m;
+ m = n;
+ m->m_off = MMAXOFF - sizeof(struct ip) - optlen;
+ m->m_len = optlen + sizeof(struct ip);
+ bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
+ } else {
+ m->m_off -= optlen;
+ m->m_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.
* If off is 0 all options are copied
if (opt == IPOPT_NOP)
optlen = 1;
else
- optlen = cp[1];
+ optlen = cp[IPOPT_OLEN];
if (optlen > cnt) /* XXX */
optlen = cnt; /* XXX */
if (off == 0 || IPOPT_COPIED(opt)) {
*dp++ = IPOPT_EOL;
return (optlen);
}
+
+/*
+ * IP socket option processing.
+ */
+ip_ctloutput(op, so, level, optname, m)
+ int op;
+ struct socket *so;
+ int level, optname;
+ struct mbuf **m;
+{
+ int error = 0;
+ struct inpcb *inp = sotoinpcb(so);
+
+ if (level != IPPROTO_IP)
+ error = EINVAL;
+ else switch (op) {
+
+ case PRCO_SETOPT:
+ switch (optname) {
+ case IP_OPTIONS:
+ return (ip_pcbopts(&inp->inp_options, *m));
+
+ default:
+ error = EINVAL;
+ break;
+ }
+ break;
+
+ case PRCO_GETOPT:
+ switch (optname) {
+ case IP_OPTIONS:
+ *m = m_get(M_WAIT, MT_SOOPTS);
+ if (inp->inp_options) {
+ (*m)->m_off = inp->inp_options->m_off;
+ (*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;
+ default:
+ error = EINVAL;
+ break;
+ }
+ break;
+ }
+ if (op == PRCO_SETOPT && *m)
+ (void)m_free(*m);
+ 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.
+ */
+ip_pcbopts(pcbopt, m)
+ 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 MAX_IPOPTLEN >= MMAXOFF - MMINOFF
+ if (m->m_off + m->m_len + sizeof(struct in_addr) > MAX_IPOPTLEN)
+ goto bad;
+#else
+ if (m->m_off + m->m_len + sizeof(struct in_addr) > MMAXOFF)
+ goto bad;
+#endif
+ 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;
+ }
+ }
+ *pcbopt = m;
+ return (0);
+
+bad:
+ (void)m_free(m);
+ return (EINVAL);
+}