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-rw-r--r--sys/netinet/ip_icmp.c520
1 files changed, 520 insertions, 0 deletions
diff --git a/sys/netinet/ip_icmp.c b/sys/netinet/ip_icmp.c
new file mode 100644
index 000000000000..b9a444c685b1
--- /dev/null
+++ b/sys/netinet/ip_icmp.c
@@ -0,0 +1,520 @@
+/*
+ * Copyright (c) 1982, 1986, 1989 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_icmp.c 7.15 (Berkeley) 4/20/91
+ * $Id: ip_icmp.c,v 1.2 1993/10/16 18:26:11 rgrimes Exp $
+ */
+
+#include "param.h"
+#include "systm.h"
+#include "malloc.h"
+#include "mbuf.h"
+#include "protosw.h"
+#include "socket.h"
+#include "time.h"
+#include "kernel.h"
+
+#include "../net/route.h"
+#include "../net/if.h"
+
+#include "in.h"
+#include "in_systm.h"
+#include "in_var.h"
+#include "ip.h"
+#include "ip_icmp.h"
+#include "icmp_var.h"
+
+/*
+ * ICMP routines: error generation, receive packet processing, and
+ * routines to turnaround packets back to the originator, and
+ * host table maintenance routines.
+ */
+#ifdef ICMPPRINTFS
+int icmpprintfs = 0;
+#endif
+
+extern struct protosw inetsw[];
+
+/*
+ * Generate an error packet of type error
+ * in response to bad packet ip.
+ */
+/*VARARGS3*/
+icmp_error(n, type, code, dest)
+ struct mbuf *n;
+ int type, code;
+ struct in_addr dest;
+{
+ register struct ip *oip = mtod(n, struct ip *), *nip;
+ register unsigned oiplen = oip->ip_hl << 2;
+ register struct icmp *icp;
+ register struct mbuf *m;
+ unsigned icmplen;
+
+#ifdef ICMPPRINTFS
+ if (icmpprintfs)
+ printf("icmp_error(%x, %d, %d)\n", oip, type, code);
+#endif
+ if (type != ICMP_REDIRECT)
+ icmpstat.icps_error++;
+ /*
+ * Don't send error if not the first fragment of message.
+ * Don't error if the old packet protocol was ICMP
+ * error message, only known informational types.
+ */
+ if (oip->ip_off &~ (IP_MF|IP_DF))
+ goto freeit;
+ if (oip->ip_p == IPPROTO_ICMP && type != ICMP_REDIRECT &&
+ n->m_len >= oiplen + ICMP_MINLEN &&
+ !ICMP_INFOTYPE(((struct icmp *)((caddr_t)oip + oiplen))->icmp_type)) {
+ icmpstat.icps_oldicmp++;
+ goto freeit;
+ }
+
+ /*
+ * First, formulate icmp message
+ */
+ m = m_gethdr(M_DONTWAIT, MT_HEADER);
+ if (m == NULL)
+ goto freeit;
+ icmplen = oiplen + min(8, oip->ip_len);
+ m->m_len = icmplen + ICMP_MINLEN;
+ MH_ALIGN(m, m->m_len);
+ icp = mtod(m, struct icmp *);
+ if ((u_int)type > ICMP_MAXTYPE)
+ panic("icmp_error");
+ icmpstat.icps_outhist[type]++;
+ icp->icmp_type = type;
+ if (type == ICMP_REDIRECT)
+ icp->icmp_gwaddr = dest;
+ else
+ icp->icmp_void = 0;
+ if (type == ICMP_PARAMPROB) {
+ icp->icmp_pptr = code;
+ code = 0;
+ }
+ icp->icmp_code = code;
+ bcopy((caddr_t)oip, (caddr_t)&icp->icmp_ip, icmplen);
+ nip = &icp->icmp_ip;
+ nip->ip_len = htons((u_short)(nip->ip_len + oiplen));
+
+ /*
+ * Now, copy old ip header (without options)
+ * in front of icmp message.
+ */
+ if (m->m_data - sizeof(struct ip) < m->m_pktdat)
+ panic("icmp len");
+ m->m_data -= sizeof(struct ip);
+ m->m_len += sizeof(struct ip);
+ m->m_pkthdr.len = m->m_len;
+ m->m_pkthdr.rcvif = n->m_pkthdr.rcvif;
+ nip = mtod(m, struct ip *);
+ bcopy((caddr_t)oip, (caddr_t)nip, oiplen);
+ nip->ip_len = m->m_len;
+ nip->ip_hl = sizeof(struct ip) >> 2;
+ nip->ip_p = IPPROTO_ICMP;
+ icmp_reflect(m);
+
+freeit:
+ m_freem(n);
+}
+
+static struct sockproto icmproto = { AF_INET, IPPROTO_ICMP };
+static struct sockaddr_in icmpsrc = { sizeof (struct sockaddr_in), AF_INET };
+static struct sockaddr_in icmpdst = { sizeof (struct sockaddr_in), AF_INET };
+static struct sockaddr_in icmpgw = { sizeof (struct sockaddr_in), AF_INET };
+struct sockaddr_in icmpmask = { 8, 0 };
+struct in_ifaddr *ifptoia();
+
+/*
+ * Process a received ICMP message.
+ */
+icmp_input(m, hlen)
+ register struct mbuf *m;
+ int hlen;
+{
+ register struct icmp *icp;
+ register struct ip *ip = mtod(m, struct ip *);
+ int icmplen = ip->ip_len;
+ register int i;
+ struct in_ifaddr *ia;
+ int (*ctlfunc)(), code;
+ extern u_char ip_protox[];
+ extern struct in_addr in_makeaddr();
+
+ /*
+ * Locate icmp structure in mbuf, and check
+ * that not corrupted and of at least minimum length.
+ */
+#ifdef ICMPPRINTFS
+ if (icmpprintfs)
+ printf("icmp_input from %x, len %d\n", ip->ip_src, icmplen);
+#endif
+ if (icmplen < ICMP_MINLEN) {
+ icmpstat.icps_tooshort++;
+ goto freeit;
+ }
+ i = hlen + MIN(icmplen, ICMP_ADVLENMIN);
+ if (m->m_len < i && (m = m_pullup(m, i)) == 0) {
+ icmpstat.icps_tooshort++;
+ return;
+ }
+ ip = mtod(m, struct ip *);
+ m->m_len -= hlen;
+ m->m_data += hlen;
+ icp = mtod(m, struct icmp *);
+ if (in_cksum(m, icmplen)) {
+ icmpstat.icps_checksum++;
+ goto freeit;
+ }
+ m->m_len += hlen;
+ m->m_data -= hlen;
+
+#ifdef ICMPPRINTFS
+ /*
+ * Message type specific processing.
+ */
+ if (icmpprintfs)
+ printf("icmp_input, type %d code %d\n", icp->icmp_type,
+ icp->icmp_code);
+#endif
+ if (icp->icmp_type > ICMP_MAXTYPE)
+ goto raw;
+ icmpstat.icps_inhist[icp->icmp_type]++;
+ code = icp->icmp_code;
+ switch (icp->icmp_type) {
+
+ case ICMP_UNREACH:
+ if (code > 5)
+ goto badcode;
+ code += PRC_UNREACH_NET;
+ goto deliver;
+
+ case ICMP_TIMXCEED:
+ if (code > 1)
+ goto badcode;
+ code += PRC_TIMXCEED_INTRANS;
+ goto deliver;
+
+ case ICMP_PARAMPROB:
+ if (code)
+ goto badcode;
+ code = PRC_PARAMPROB;
+ goto deliver;
+
+ case ICMP_SOURCEQUENCH:
+ if (code)
+ goto badcode;
+ code = PRC_QUENCH;
+ deliver:
+ /*
+ * Problem with datagram; advise higher level routines.
+ */
+ if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp) ||
+ icp->icmp_ip.ip_hl < (sizeof(struct ip) >> 2)) {
+ icmpstat.icps_badlen++;
+ goto freeit;
+ }
+ NTOHS(icp->icmp_ip.ip_len);
+#ifdef ICMPPRINTFS
+ if (icmpprintfs)
+ printf("deliver to protocol %d\n", icp->icmp_ip.ip_p);
+#endif
+ icmpsrc.sin_addr = icp->icmp_ip.ip_dst;
+ if (ctlfunc = inetsw[ip_protox[icp->icmp_ip.ip_p]].pr_ctlinput)
+ (*ctlfunc)(code, (struct sockaddr *)&icmpsrc,
+ (caddr_t) &icp->icmp_ip);
+ break;
+
+ badcode:
+ icmpstat.icps_badcode++;
+ break;
+
+ case ICMP_ECHO:
+ icp->icmp_type = ICMP_ECHOREPLY;
+ goto reflect;
+
+ case ICMP_TSTAMP:
+ if (icmplen < ICMP_TSLEN) {
+ icmpstat.icps_badlen++;
+ break;
+ }
+ icp->icmp_type = ICMP_TSTAMPREPLY;
+ icp->icmp_rtime = iptime();
+ icp->icmp_ttime = icp->icmp_rtime; /* bogus, do later! */
+ goto reflect;
+
+ case ICMP_IREQ:
+#define satosin(sa) ((struct sockaddr_in *)(sa))
+ if (in_netof(ip->ip_src) == 0 &&
+ (ia = ifptoia(m->m_pkthdr.rcvif)))
+ ip->ip_src = in_makeaddr(in_netof(IA_SIN(ia)->sin_addr),
+ in_lnaof(ip->ip_src));
+ icp->icmp_type = ICMP_IREQREPLY;
+ goto reflect;
+
+ case ICMP_MASKREQ:
+ if (icmplen < ICMP_MASKLEN ||
+ (ia = ifptoia(m->m_pkthdr.rcvif)) == 0)
+ break;
+ icp->icmp_type = ICMP_MASKREPLY;
+ icp->icmp_mask = ia->ia_sockmask.sin_addr.s_addr;
+ if (ip->ip_src.s_addr == 0) {
+ if (ia->ia_ifp->if_flags & IFF_BROADCAST)
+ ip->ip_src = satosin(&ia->ia_broadaddr)->sin_addr;
+ else if (ia->ia_ifp->if_flags & IFF_POINTOPOINT)
+ ip->ip_src = satosin(&ia->ia_dstaddr)->sin_addr;
+ }
+reflect:
+ ip->ip_len += hlen; /* since ip_input deducts this */
+ icmpstat.icps_reflect++;
+ icmpstat.icps_outhist[icp->icmp_type]++;
+ icmp_reflect(m);
+ return;
+
+ case ICMP_REDIRECT:
+ if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp)) {
+ icmpstat.icps_badlen++;
+ break;
+ }
+ /*
+ * Short circuit routing redirects to force
+ * immediate change in the kernel's routing
+ * tables. The message is also handed to anyone
+ * listening on a raw socket (e.g. the routing
+ * daemon for use in updating its tables).
+ */
+ icmpgw.sin_addr = ip->ip_src;
+ icmpdst.sin_addr = icp->icmp_gwaddr;
+#ifdef ICMPPRINTFS
+ if (icmpprintfs)
+ printf("redirect dst %x to %x\n", icp->icmp_ip.ip_dst,
+ icp->icmp_gwaddr);
+#endif
+ if (code == ICMP_REDIRECT_NET || code == ICMP_REDIRECT_TOSNET) {
+ u_long in_netof();
+ icmpsrc.sin_addr =
+ in_makeaddr(in_netof(icp->icmp_ip.ip_dst), INADDR_ANY);
+ in_sockmaskof(icp->icmp_ip.ip_dst, &icmpmask);
+ rtredirect((struct sockaddr *)&icmpsrc,
+ (struct sockaddr *)&icmpdst,
+ (struct sockaddr *)&icmpmask, RTF_GATEWAY,
+ (struct sockaddr *)&icmpgw, (struct rtentry **)0);
+ icmpsrc.sin_addr = icp->icmp_ip.ip_dst;
+ pfctlinput(PRC_REDIRECT_NET,
+ (struct sockaddr *)&icmpsrc);
+ } else {
+ icmpsrc.sin_addr = icp->icmp_ip.ip_dst;
+ rtredirect((struct sockaddr *)&icmpsrc,
+ (struct sockaddr *)&icmpdst,
+ (struct sockaddr *)0, RTF_GATEWAY | RTF_HOST,
+ (struct sockaddr *)&icmpgw, (struct rtentry **)0);
+ pfctlinput(PRC_REDIRECT_HOST,
+ (struct sockaddr *)&icmpsrc);
+ }
+ break;
+
+ /*
+ * No kernel processing for the following;
+ * just fall through to send to raw listener.
+ */
+ case ICMP_ECHOREPLY:
+ case ICMP_TSTAMPREPLY:
+ case ICMP_IREQREPLY:
+ case ICMP_MASKREPLY:
+ default:
+ break;
+ }
+
+raw:
+ icmpsrc.sin_addr = ip->ip_src;
+ icmpdst.sin_addr = ip->ip_dst;
+ (void) raw_input(m, &icmproto, (struct sockaddr *)&icmpsrc,
+ (struct sockaddr *)&icmpdst);
+ return;
+
+freeit:
+ m_freem(m);
+}
+
+/*
+ * Reflect the ip packet back to the source
+ */
+icmp_reflect(m)
+ struct mbuf *m;
+{
+ register struct ip *ip = mtod(m, struct ip *);
+ register struct in_ifaddr *ia;
+ struct in_addr t;
+ struct mbuf *opts = 0, *ip_srcroute();
+ int optlen = (ip->ip_hl << 2) - sizeof(struct ip);
+
+ t = ip->ip_dst;
+ ip->ip_dst = ip->ip_src;
+ /*
+ * If the incoming packet was addressed directly to us,
+ * use dst as the src for the reply. Otherwise (broadcast
+ * or anonymous), use the address which corresponds
+ * to the incoming interface.
+ */
+ for (ia = in_ifaddr; ia; ia = ia->ia_next) {
+ if (t.s_addr == IA_SIN(ia)->sin_addr.s_addr)
+ break;
+ if ((ia->ia_ifp->if_flags & IFF_BROADCAST) &&
+ t.s_addr == satosin(&ia->ia_broadaddr)->sin_addr.s_addr)
+ break;
+ }
+ if (ia == (struct in_ifaddr *)0)
+ ia = ifptoia(m->m_pkthdr.rcvif);
+ if (ia == (struct in_ifaddr *)0)
+ ia = in_ifaddr;
+ t = IA_SIN(ia)->sin_addr;
+ ip->ip_src = t;
+ ip->ip_ttl = MAXTTL;
+
+ if (optlen > 0) {
+ register u_char *cp;
+ int opt, cnt;
+ u_int len;
+
+ /*
+ * Retrieve any source routing from the incoming packet;
+ * add on any record-route or timestamp options.
+ */
+ cp = (u_char *) (ip + 1);
+ if ((opts = ip_srcroute()) == 0 &&
+ (opts = m_gethdr(M_DONTWAIT, MT_HEADER))) {
+ opts->m_len = sizeof(struct in_addr);
+ mtod(opts, struct in_addr *)->s_addr = 0;
+ }
+ if (opts) {
+#ifdef ICMPPRINTFS
+ if (icmpprintfs)
+ printf("icmp_reflect optlen %d rt %d => ",
+ optlen, opts->m_len);
+#endif
+ for (cnt = optlen; cnt > 0; cnt -= len, cp += len) {
+ opt = cp[IPOPT_OPTVAL];
+ if (opt == IPOPT_EOL)
+ break;
+ if (opt == IPOPT_NOP)
+ len = 1;
+ else {
+ len = cp[IPOPT_OLEN];
+ if (len <= 0 || len > cnt)
+ break;
+ }
+ /*
+ * should check for overflow, but it "can't happen"
+ */
+ if (opt == IPOPT_RR || opt == IPOPT_TS) {
+ bcopy((caddr_t)cp,
+ mtod(opts, caddr_t) + opts->m_len, len);
+ opts->m_len += len;
+ }
+ }
+ if (opts->m_len % 4 != 0) {
+ *(mtod(opts, caddr_t) + opts->m_len) = IPOPT_EOL;
+ opts->m_len++;
+ }
+#ifdef ICMPPRINTFS
+ if (icmpprintfs)
+ printf("%d\n", opts->m_len);
+#endif
+ }
+ /*
+ * Now strip out original options by copying rest of first
+ * mbuf's data back, and adjust the IP length.
+ */
+ ip->ip_len -= optlen;
+ ip->ip_hl = sizeof(struct ip) >> 2;
+ m->m_len -= optlen;
+ if (m->m_flags & M_PKTHDR)
+ m->m_pkthdr.len -= optlen;
+ optlen += sizeof(struct ip);
+ bcopy((caddr_t)ip + optlen, (caddr_t)(ip + 1),
+ (unsigned)(m->m_len - sizeof(struct ip)));
+ }
+ icmp_send(m, opts);
+ if (opts)
+ (void)m_free(opts);
+}
+
+struct in_ifaddr *
+ifptoia(ifp)
+ struct ifnet *ifp;
+{
+ register struct in_ifaddr *ia;
+
+ for (ia = in_ifaddr; ia; ia = ia->ia_next)
+ if (ia->ia_ifp == ifp)
+ return (ia);
+ return ((struct in_ifaddr *)0);
+}
+
+/*
+ * Send an icmp packet back to the ip level,
+ * after supplying a checksum.
+ */
+icmp_send(m, opts)
+ register struct mbuf *m;
+ struct mbuf *opts;
+{
+ register struct ip *ip = mtod(m, struct ip *);
+ register int hlen;
+ register struct icmp *icp;
+
+ hlen = ip->ip_hl << 2;
+ m->m_data += hlen;
+ m->m_len -= hlen;
+ icp = mtod(m, struct icmp *);
+ icp->icmp_cksum = 0;
+ icp->icmp_cksum = in_cksum(m, ip->ip_len - hlen);
+ m->m_data -= hlen;
+ m->m_len += hlen;
+#ifdef ICMPPRINTFS
+ if (icmpprintfs)
+ printf("icmp_send dst %x src %x\n", ip->ip_dst, ip->ip_src);
+#endif
+ (void) ip_output(m, opts, (struct route *)0, 0);
+}
+
+n_time
+iptime()
+{
+ struct timeval atv;
+ u_long t;
+
+ microtime(&atv);
+ t = (atv.tv_sec % (24*60*60)) * 1000 + atv.tv_usec / 1000;
+ return (htonl(t));
+}
generated by cgit v1.2.3 (git 2.25.1) at 2026-03-25 00:24:40 +0000