root / slirp / ip_input.c @ 460fec67
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/*
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* Copyright (c) 1982, 1986, 1988, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
|
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)ip_input.c 8.2 (Berkeley) 1/4/94
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* ip_input.c,v 1.11 1994/11/16 10:17:08 jkh Exp
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*/
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/*
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* Changes and additions relating to SLiRP are
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* Copyright (c) 1995 Danny Gasparovski.
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*
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* Please read the file COPYRIGHT for the
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* terms and conditions of the copyright.
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*/
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#include <slirp.h> |
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#include <osdep.h> |
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#include "ip_icmp.h" |
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|
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static struct ip *ip_reass(Slirp *slirp, struct ip *ip, struct ipq *fp); |
| 46 |
static void ip_freef(Slirp *slirp, struct ipq *fp); |
| 47 |
static void ip_enq(register struct ipasfrag *p, |
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register struct ipasfrag *prev); |
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static void ip_deq(register struct ipasfrag *p); |
| 50 |
|
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/*
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* IP initialization: fill in IP protocol switch table.
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* All protocols not implemented in kernel go to raw IP protocol handler.
|
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*/
|
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void
|
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ip_init(Slirp *slirp) |
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{
|
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slirp->ipq.ip_link.next = slirp->ipq.ip_link.prev = &slirp->ipq.ip_link; |
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udp_init(slirp); |
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tcp_init(slirp); |
| 61 |
} |
| 62 |
|
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/*
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* Ip input routine. Checksum and byte swap header. If fragmented
|
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* try to reassemble. Process options. Pass to next level.
|
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*/
|
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void
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ip_input(struct mbuf *m)
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{
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Slirp *slirp = m->slirp; |
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register struct ip *ip; |
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int hlen;
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|
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DEBUG_CALL("ip_input");
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DEBUG_ARG("m = %lx", (long)m); |
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DEBUG_ARG("m_len = %d", m->m_len);
|
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|
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if (m->m_len < sizeof (struct ip)) { |
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return;
|
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} |
| 81 |
|
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ip = mtod(m, struct ip *);
|
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|
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if (ip->ip_v != IPVERSION) {
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goto bad;
|
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} |
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|
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hlen = ip->ip_hl << 2;
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if (hlen<sizeof(struct ip ) || hlen>m->m_len) {/* min header length */ |
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goto bad; /* or packet too short */ |
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} |
| 92 |
|
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/* keep ip header intact for ICMP reply
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* ip->ip_sum = cksum(m, hlen);
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* if (ip->ip_sum) {
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*/
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if(cksum(m,hlen)) {
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goto bad;
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} |
| 100 |
|
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/*
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* Convert fields to host representation.
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*/
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NTOHS(ip->ip_len); |
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if (ip->ip_len < hlen) {
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goto bad;
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} |
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NTOHS(ip->ip_id); |
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NTOHS(ip->ip_off); |
| 110 |
|
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/*
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* Check that the amount of data in the buffers
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* is as at least much as the IP header would have us expect.
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* Trim mbufs if longer than we expect.
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* Drop packet if shorter than we expect.
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*/
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if (m->m_len < ip->ip_len) {
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goto bad;
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} |
| 120 |
|
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if (slirp->restricted) {
|
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if ((ip->ip_dst.s_addr & slirp->vnetwork_mask.s_addr) ==
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slirp->vnetwork_addr.s_addr) {
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if (ip->ip_dst.s_addr == 0xffffffff && ip->ip_p != IPPROTO_UDP) |
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goto bad;
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} else {
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uint32_t inv_mask = ~slirp->vnetwork_mask.s_addr; |
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struct ex_list *ex_ptr;
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|
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if ((ip->ip_dst.s_addr & inv_mask) == inv_mask) {
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goto bad;
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} |
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for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next)
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if (ex_ptr->ex_addr.s_addr == ip->ip_dst.s_addr)
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break;
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|
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if (!ex_ptr)
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goto bad;
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} |
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} |
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|
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/* Should drop packet if mbuf too long? hmmm... */
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if (m->m_len > ip->ip_len)
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m_adj(m, ip->ip_len - m->m_len); |
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|
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/* check ip_ttl for a correct ICMP reply */
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if(ip->ip_ttl==0 || ip->ip_ttl==1) { |
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icmp_error(m, ICMP_TIMXCEED,ICMP_TIMXCEED_INTRANS, 0,"ttl"); |
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goto bad;
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} |
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|
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/*
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* If offset or IP_MF are set, must reassemble.
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* Otherwise, nothing need be done.
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* (We could look in the reassembly queue to see
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* if the packet was previously fragmented,
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* but it's not worth the time; just let them time out.)
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*
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* XXX This should fail, don't fragment yet
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*/
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if (ip->ip_off &~ IP_DF) {
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register struct ipq *fp; |
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struct qlink *l;
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/*
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* Look for queue of fragments
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* of this datagram.
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*/
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for (l = slirp->ipq.ip_link.next; l != &slirp->ipq.ip_link;
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l = l->next) {
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fp = container_of(l, struct ipq, ip_link);
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if (ip->ip_id == fp->ipq_id &&
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ip->ip_src.s_addr == fp->ipq_src.s_addr && |
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ip->ip_dst.s_addr == fp->ipq_dst.s_addr && |
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ip->ip_p == fp->ipq_p) |
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goto found;
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} |
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fp = NULL;
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found:
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|
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/*
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* Adjust ip_len to not reflect header,
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* set ip_mff if more fragments are expected,
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* convert offset of this to bytes.
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*/
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ip->ip_len -= hlen; |
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if (ip->ip_off & IP_MF)
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ip->ip_tos |= 1;
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else
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ip->ip_tos &= ~1;
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|
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ip->ip_off <<= 3;
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|
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/*
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* If datagram marked as having more fragments
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* or if this is not the first fragment,
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* attempt reassembly; if it succeeds, proceed.
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*/
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if (ip->ip_tos & 1 || ip->ip_off) { |
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ip = ip_reass(slirp, ip, fp); |
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if (ip == NULL) |
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return;
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m = dtom(slirp, ip); |
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} else
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if (fp)
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ip_freef(slirp, fp); |
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} else
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ip->ip_len -= hlen; |
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|
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/*
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* Switch out to protocol's input routine.
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*/
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switch (ip->ip_p) {
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case IPPROTO_TCP:
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tcp_input(m, hlen, (struct socket *)NULL); |
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break;
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case IPPROTO_UDP:
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udp_input(m, hlen); |
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break;
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case IPPROTO_ICMP:
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icmp_input(m, hlen); |
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break;
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default:
|
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m_free(m); |
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} |
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return;
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bad:
|
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m_freem(m); |
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return;
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} |
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|
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#define iptofrag(P) ((struct ipasfrag *)(((char*)(P)) - sizeof(struct qlink))) |
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#define fragtoip(P) ((struct ip*)(((char*)(P)) + sizeof(struct qlink))) |
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/*
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* Take incoming datagram fragment and try to
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* reassemble it into whole datagram. If a chain for
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* reassembly of this datagram already exists, then it
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* is given as fp; otherwise have to make a chain.
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*/
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static struct ip * |
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ip_reass(Slirp *slirp, struct ip *ip, struct ipq *fp) |
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{
|
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register struct mbuf *m = dtom(slirp, ip); |
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register struct ipasfrag *q; |
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int hlen = ip->ip_hl << 2; |
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int i, next;
|
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|
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DEBUG_CALL("ip_reass");
|
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DEBUG_ARG("ip = %lx", (long)ip); |
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DEBUG_ARG("fp = %lx", (long)fp); |
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DEBUG_ARG("m = %lx", (long)m); |
| 252 |
|
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/*
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* Presence of header sizes in mbufs
|
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* would confuse code below.
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* Fragment m_data is concatenated.
|
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*/
|
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m->m_data += hlen; |
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m->m_len -= hlen; |
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|
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/*
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* If first fragment to arrive, create a reassembly queue.
|
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*/
|
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if (fp == NULL) { |
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struct mbuf *t = m_get(slirp);
|
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|
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if (t == NULL) { |
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goto dropfrag;
|
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} |
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fp = mtod(t, struct ipq *);
|
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insque(&fp->ip_link, &slirp->ipq.ip_link); |
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fp->ipq_ttl = IPFRAGTTL; |
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fp->ipq_p = ip->ip_p; |
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fp->ipq_id = ip->ip_id; |
| 275 |
fp->frag_link.next = fp->frag_link.prev = &fp->frag_link; |
| 276 |
fp->ipq_src = ip->ip_src; |
| 277 |
fp->ipq_dst = ip->ip_dst; |
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q = (struct ipasfrag *)fp;
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goto insert;
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} |
| 281 |
|
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/*
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* Find a segment which begins after this one does.
|
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*/
|
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for (q = fp->frag_link.next; q != (struct ipasfrag *)&fp->frag_link; |
| 286 |
q = q->ipf_next) |
| 287 |
if (q->ipf_off > ip->ip_off)
|
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break;
|
| 289 |
|
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/*
|
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* If there is a preceding segment, it may provide some of
|
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* our data already. If so, drop the data from the incoming
|
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* segment. If it provides all of our data, drop us.
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*/
|
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if (q->ipf_prev != &fp->frag_link) {
|
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struct ipasfrag *pq = q->ipf_prev;
|
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i = pq->ipf_off + pq->ipf_len - ip->ip_off; |
| 298 |
if (i > 0) { |
| 299 |
if (i >= ip->ip_len)
|
| 300 |
goto dropfrag;
|
| 301 |
m_adj(dtom(slirp, ip), i); |
| 302 |
ip->ip_off += i; |
| 303 |
ip->ip_len -= i; |
| 304 |
} |
| 305 |
} |
| 306 |
|
| 307 |
/*
|
| 308 |
* While we overlap succeeding segments trim them or,
|
| 309 |
* if they are completely covered, dequeue them.
|
| 310 |
*/
|
| 311 |
while (q != (struct ipasfrag*)&fp->frag_link && |
| 312 |
ip->ip_off + ip->ip_len > q->ipf_off) {
|
| 313 |
i = (ip->ip_off + ip->ip_len) - q->ipf_off; |
| 314 |
if (i < q->ipf_len) {
|
| 315 |
q->ipf_len -= i; |
| 316 |
q->ipf_off += i; |
| 317 |
m_adj(dtom(slirp, q), i); |
| 318 |
break;
|
| 319 |
} |
| 320 |
q = q->ipf_next; |
| 321 |
m_freem(dtom(slirp, q->ipf_prev)); |
| 322 |
ip_deq(q->ipf_prev); |
| 323 |
} |
| 324 |
|
| 325 |
insert:
|
| 326 |
/*
|
| 327 |
* Stick new segment in its place;
|
| 328 |
* check for complete reassembly.
|
| 329 |
*/
|
| 330 |
ip_enq(iptofrag(ip), q->ipf_prev); |
| 331 |
next = 0;
|
| 332 |
for (q = fp->frag_link.next; q != (struct ipasfrag*)&fp->frag_link; |
| 333 |
q = q->ipf_next) {
|
| 334 |
if (q->ipf_off != next)
|
| 335 |
return NULL; |
| 336 |
next += q->ipf_len; |
| 337 |
} |
| 338 |
if (((struct ipasfrag *)(q->ipf_prev))->ipf_tos & 1) |
| 339 |
return NULL; |
| 340 |
|
| 341 |
/*
|
| 342 |
* Reassembly is complete; concatenate fragments.
|
| 343 |
*/
|
| 344 |
q = fp->frag_link.next; |
| 345 |
m = dtom(slirp, q); |
| 346 |
|
| 347 |
q = (struct ipasfrag *) q->ipf_next;
|
| 348 |
while (q != (struct ipasfrag*)&fp->frag_link) { |
| 349 |
struct mbuf *t = dtom(slirp, q);
|
| 350 |
q = (struct ipasfrag *) q->ipf_next;
|
| 351 |
m_cat(m, t); |
| 352 |
} |
| 353 |
|
| 354 |
/*
|
| 355 |
* Create header for new ip packet by
|
| 356 |
* modifying header of first packet;
|
| 357 |
* dequeue and discard fragment reassembly header.
|
| 358 |
* Make header visible.
|
| 359 |
*/
|
| 360 |
q = fp->frag_link.next; |
| 361 |
|
| 362 |
/*
|
| 363 |
* If the fragments concatenated to an mbuf that's
|
| 364 |
* bigger than the total size of the fragment, then and
|
| 365 |
* m_ext buffer was alloced. But fp->ipq_next points to
|
| 366 |
* the old buffer (in the mbuf), so we must point ip
|
| 367 |
* into the new buffer.
|
| 368 |
*/
|
| 369 |
if (m->m_flags & M_EXT) {
|
| 370 |
int delta = (char *)q - m->m_dat; |
| 371 |
q = (struct ipasfrag *)(m->m_ext + delta);
|
| 372 |
} |
| 373 |
|
| 374 |
ip = fragtoip(q); |
| 375 |
ip->ip_len = next; |
| 376 |
ip->ip_tos &= ~1;
|
| 377 |
ip->ip_src = fp->ipq_src; |
| 378 |
ip->ip_dst = fp->ipq_dst; |
| 379 |
remque(&fp->ip_link); |
| 380 |
(void) m_free(dtom(slirp, fp));
|
| 381 |
m->m_len += (ip->ip_hl << 2);
|
| 382 |
m->m_data -= (ip->ip_hl << 2);
|
| 383 |
|
| 384 |
return ip;
|
| 385 |
|
| 386 |
dropfrag:
|
| 387 |
m_freem(m); |
| 388 |
return NULL; |
| 389 |
} |
| 390 |
|
| 391 |
/*
|
| 392 |
* Free a fragment reassembly header and all
|
| 393 |
* associated datagrams.
|
| 394 |
*/
|
| 395 |
static void |
| 396 |
ip_freef(Slirp *slirp, struct ipq *fp)
|
| 397 |
{
|
| 398 |
register struct ipasfrag *q, *p; |
| 399 |
|
| 400 |
for (q = fp->frag_link.next; q != (struct ipasfrag*)&fp->frag_link; q = p) { |
| 401 |
p = q->ipf_next; |
| 402 |
ip_deq(q); |
| 403 |
m_freem(dtom(slirp, q)); |
| 404 |
} |
| 405 |
remque(&fp->ip_link); |
| 406 |
(void) m_free(dtom(slirp, fp));
|
| 407 |
} |
| 408 |
|
| 409 |
/*
|
| 410 |
* Put an ip fragment on a reassembly chain.
|
| 411 |
* Like insque, but pointers in middle of structure.
|
| 412 |
*/
|
| 413 |
static void |
| 414 |
ip_enq(register struct ipasfrag *p, register struct ipasfrag *prev) |
| 415 |
{
|
| 416 |
DEBUG_CALL("ip_enq");
|
| 417 |
DEBUG_ARG("prev = %lx", (long)prev); |
| 418 |
p->ipf_prev = prev; |
| 419 |
p->ipf_next = prev->ipf_next; |
| 420 |
((struct ipasfrag *)(prev->ipf_next))->ipf_prev = p;
|
| 421 |
prev->ipf_next = p; |
| 422 |
} |
| 423 |
|
| 424 |
/*
|
| 425 |
* To ip_enq as remque is to insque.
|
| 426 |
*/
|
| 427 |
static void |
| 428 |
ip_deq(register struct ipasfrag *p) |
| 429 |
{
|
| 430 |
((struct ipasfrag *)(p->ipf_prev))->ipf_next = p->ipf_next;
|
| 431 |
((struct ipasfrag *)(p->ipf_next))->ipf_prev = p->ipf_prev;
|
| 432 |
} |
| 433 |
|
| 434 |
/*
|
| 435 |
* IP timer processing;
|
| 436 |
* if a timer expires on a reassembly
|
| 437 |
* queue, discard it.
|
| 438 |
*/
|
| 439 |
void
|
| 440 |
ip_slowtimo(Slirp *slirp) |
| 441 |
{
|
| 442 |
struct qlink *l;
|
| 443 |
|
| 444 |
DEBUG_CALL("ip_slowtimo");
|
| 445 |
|
| 446 |
l = slirp->ipq.ip_link.next; |
| 447 |
|
| 448 |
if (l == NULL) |
| 449 |
return;
|
| 450 |
|
| 451 |
while (l != &slirp->ipq.ip_link) {
|
| 452 |
struct ipq *fp = container_of(l, struct ipq, ip_link); |
| 453 |
l = l->next; |
| 454 |
if (--fp->ipq_ttl == 0) { |
| 455 |
ip_freef(slirp, fp); |
| 456 |
} |
| 457 |
} |
| 458 |
} |
| 459 |
|
| 460 |
/*
|
| 461 |
* Do option processing on a datagram,
|
| 462 |
* possibly discarding it if bad options are encountered,
|
| 463 |
* or forwarding it if source-routed.
|
| 464 |
* Returns 1 if packet has been forwarded/freed,
|
| 465 |
* 0 if the packet should be processed further.
|
| 466 |
*/
|
| 467 |
|
| 468 |
#ifdef notdef
|
| 469 |
|
| 470 |
int
|
| 471 |
ip_dooptions(m) |
| 472 |
struct mbuf *m;
|
| 473 |
{
|
| 474 |
register struct ip *ip = mtod(m, struct ip *); |
| 475 |
register u_char *cp;
|
| 476 |
register struct ip_timestamp *ipt; |
| 477 |
register struct in_ifaddr *ia; |
| 478 |
int opt, optlen, cnt, off, code, type, forward = 0; |
| 479 |
struct in_addr *sin, dst;
|
| 480 |
typedef u_int32_t n_time;
|
| 481 |
n_time ntime; |
| 482 |
|
| 483 |
dst = ip->ip_dst; |
| 484 |
cp = (u_char *)(ip + 1);
|
| 485 |
cnt = (ip->ip_hl << 2) - sizeof (struct ip); |
| 486 |
for (; cnt > 0; cnt -= optlen, cp += optlen) { |
| 487 |
opt = cp[IPOPT_OPTVAL]; |
| 488 |
if (opt == IPOPT_EOL)
|
| 489 |
break;
|
| 490 |
if (opt == IPOPT_NOP)
|
| 491 |
optlen = 1;
|
| 492 |
else {
|
| 493 |
optlen = cp[IPOPT_OLEN]; |
| 494 |
if (optlen <= 0 || optlen > cnt) { |
| 495 |
code = &cp[IPOPT_OLEN] - (u_char *)ip; |
| 496 |
goto bad;
|
| 497 |
} |
| 498 |
} |
| 499 |
switch (opt) {
|
| 500 |
|
| 501 |
default:
|
| 502 |
break;
|
| 503 |
|
| 504 |
/*
|
| 505 |
* Source routing with record.
|
| 506 |
* Find interface with current destination address.
|
| 507 |
* If none on this machine then drop if strictly routed,
|
| 508 |
* or do nothing if loosely routed.
|
| 509 |
* Record interface address and bring up next address
|
| 510 |
* component. If strictly routed make sure next
|
| 511 |
* address is on directly accessible net.
|
| 512 |
*/
|
| 513 |
case IPOPT_LSRR:
|
| 514 |
case IPOPT_SSRR:
|
| 515 |
if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
|
| 516 |
code = &cp[IPOPT_OFFSET] - (u_char *)ip; |
| 517 |
goto bad;
|
| 518 |
} |
| 519 |
ipaddr.sin_addr = ip->ip_dst; |
| 520 |
ia = (struct in_ifaddr *)
|
| 521 |
ifa_ifwithaddr((struct sockaddr *)&ipaddr);
|
| 522 |
if (ia == 0) { |
| 523 |
if (opt == IPOPT_SSRR) {
|
| 524 |
type = ICMP_UNREACH; |
| 525 |
code = ICMP_UNREACH_SRCFAIL; |
| 526 |
goto bad;
|
| 527 |
} |
| 528 |
/*
|
| 529 |
* Loose routing, and not at next destination
|
| 530 |
* yet; nothing to do except forward.
|
| 531 |
*/
|
| 532 |
break;
|
| 533 |
} |
| 534 |
off--; / * 0 origin * /
|
| 535 |
if (off > optlen - sizeof(struct in_addr)) { |
| 536 |
/*
|
| 537 |
* End of source route. Should be for us.
|
| 538 |
*/
|
| 539 |
save_rte(cp, ip->ip_src); |
| 540 |
break;
|
| 541 |
} |
| 542 |
/*
|
| 543 |
* locate outgoing interface
|
| 544 |
*/
|
| 545 |
bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, |
| 546 |
sizeof(ipaddr.sin_addr));
|
| 547 |
if (opt == IPOPT_SSRR) {
|
| 548 |
#define INA struct in_ifaddr * |
| 549 |
#define SA struct sockaddr * |
| 550 |
if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0) |
| 551 |
ia = (INA)ifa_ifwithnet((SA)&ipaddr); |
| 552 |
} else
|
| 553 |
ia = ip_rtaddr(ipaddr.sin_addr); |
| 554 |
if (ia == 0) { |
| 555 |
type = ICMP_UNREACH; |
| 556 |
code = ICMP_UNREACH_SRCFAIL; |
| 557 |
goto bad;
|
| 558 |
} |
| 559 |
ip->ip_dst = ipaddr.sin_addr; |
| 560 |
bcopy((caddr_t)&(IA_SIN(ia)->sin_addr), |
| 561 |
(caddr_t)(cp + off), sizeof(struct in_addr)); |
| 562 |
cp[IPOPT_OFFSET] += sizeof(struct in_addr); |
| 563 |
/*
|
| 564 |
* Let ip_intr's mcast routing check handle mcast pkts
|
| 565 |
*/
|
| 566 |
forward = !IN_MULTICAST(ntohl(ip->ip_dst.s_addr)); |
| 567 |
break;
|
| 568 |
|
| 569 |
case IPOPT_RR:
|
| 570 |
if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) {
|
| 571 |
code = &cp[IPOPT_OFFSET] - (u_char *)ip; |
| 572 |
goto bad;
|
| 573 |
} |
| 574 |
/*
|
| 575 |
* If no space remains, ignore.
|
| 576 |
*/
|
| 577 |
off--; * 0 origin *
|
| 578 |
if (off > optlen - sizeof(struct in_addr)) |
| 579 |
break;
|
| 580 |
bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, |
| 581 |
sizeof(ipaddr.sin_addr));
|
| 582 |
/*
|
| 583 |
* locate outgoing interface; if we're the destination,
|
| 584 |
* use the incoming interface (should be same).
|
| 585 |
*/
|
| 586 |
if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && |
| 587 |
(ia = ip_rtaddr(ipaddr.sin_addr)) == 0) {
|
| 588 |
type = ICMP_UNREACH; |
| 589 |
code = ICMP_UNREACH_HOST; |
| 590 |
goto bad;
|
| 591 |
} |
| 592 |
bcopy((caddr_t)&(IA_SIN(ia)->sin_addr), |
| 593 |
(caddr_t)(cp + off), sizeof(struct in_addr)); |
| 594 |
cp[IPOPT_OFFSET] += sizeof(struct in_addr); |
| 595 |
break;
|
| 596 |
|
| 597 |
case IPOPT_TS:
|
| 598 |
code = cp - (u_char *)ip; |
| 599 |
ipt = (struct ip_timestamp *)cp;
|
| 600 |
if (ipt->ipt_len < 5) |
| 601 |
goto bad;
|
| 602 |
if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { |
| 603 |
if (++ipt->ipt_oflw == 0) |
| 604 |
goto bad;
|
| 605 |
break;
|
| 606 |
} |
| 607 |
sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); |
| 608 |
switch (ipt->ipt_flg) {
|
| 609 |
|
| 610 |
case IPOPT_TS_TSONLY:
|
| 611 |
break;
|
| 612 |
|
| 613 |
case IPOPT_TS_TSANDADDR:
|
| 614 |
if (ipt->ipt_ptr + sizeof(n_time) + |
| 615 |
sizeof(struct in_addr) > ipt->ipt_len) |
| 616 |
goto bad;
|
| 617 |
ipaddr.sin_addr = dst; |
| 618 |
ia = (INA)ifaof_ i f p foraddr((SA)&ipaddr, |
| 619 |
m->m_pkthdr.rcvif); |
| 620 |
if (ia == 0) |
| 621 |
continue;
|
| 622 |
bcopy((caddr_t)&IA_SIN(ia)->sin_addr, |
| 623 |
(caddr_t)sin, sizeof(struct in_addr)); |
| 624 |
ipt->ipt_ptr += sizeof(struct in_addr); |
| 625 |
break;
|
| 626 |
|
| 627 |
case IPOPT_TS_PRESPEC:
|
| 628 |
if (ipt->ipt_ptr + sizeof(n_time) + |
| 629 |
sizeof(struct in_addr) > ipt->ipt_len) |
| 630 |
goto bad;
|
| 631 |
bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, |
| 632 |
sizeof(struct in_addr)); |
| 633 |
if (ifa_ifwithaddr((SA)&ipaddr) == 0) |
| 634 |
continue;
|
| 635 |
ipt->ipt_ptr += sizeof(struct in_addr); |
| 636 |
break;
|
| 637 |
|
| 638 |
default:
|
| 639 |
goto bad;
|
| 640 |
} |
| 641 |
ntime = iptime(); |
| 642 |
bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1,
|
| 643 |
sizeof(n_time));
|
| 644 |
ipt->ipt_ptr += sizeof(n_time);
|
| 645 |
} |
| 646 |
} |
| 647 |
if (forward) {
|
| 648 |
ip_forward(m, 1);
|
| 649 |
return (1); |
| 650 |
} |
| 651 |
} |
| 652 |
} |
| 653 |
return (0); |
| 654 |
bad:
|
| 655 |
icmp_error(m, type, code, 0, 0); |
| 656 |
|
| 657 |
return (1); |
| 658 |
} |
| 659 |
|
| 660 |
#endif /* notdef */ |
| 661 |
|
| 662 |
/*
|
| 663 |
* Strip out IP options, at higher
|
| 664 |
* level protocol in the kernel.
|
| 665 |
* Second argument is buffer to which options
|
| 666 |
* will be moved, and return value is their length.
|
| 667 |
* (XXX) should be deleted; last arg currently ignored.
|
| 668 |
*/
|
| 669 |
void
|
| 670 |
ip_stripoptions(register struct mbuf *m, struct mbuf *mopt) |
| 671 |
{
|
| 672 |
register int i; |
| 673 |
struct ip *ip = mtod(m, struct ip *); |
| 674 |
register caddr_t opts;
|
| 675 |
int olen;
|
| 676 |
|
| 677 |
olen = (ip->ip_hl<<2) - sizeof (struct ip); |
| 678 |
opts = (caddr_t)(ip + 1);
|
| 679 |
i = m->m_len - (sizeof (struct ip) + olen); |
| 680 |
memcpy(opts, opts + olen, (unsigned)i);
|
| 681 |
m->m_len -= olen; |
| 682 |
|
| 683 |
ip->ip_hl = sizeof(struct ip) >> 2; |
| 684 |
} |