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/* $OpenBSD: print-icmp.c,v 1.25 2015/01/16 06:40:21 deraadt Exp $ */
/*
* Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996
* 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: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#include <sys/time.h>
#include <sys/socket.h>
struct mbuf;
struct rtentry;
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/tcp.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include "interface.h"
#include "addrtoname.h"
#include "extract.h" /* must come after interface.h */
/* rfc1700 */
#ifndef ICMP_UNREACH_NET_UNKNOWN
#define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */
#endif
#ifndef ICMP_UNREACH_HOST_UNKNOWN
#define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */
#endif
#ifndef ICMP_UNREACH_ISOLATED
#define ICMP_UNREACH_ISOLATED 8 /* source host isolated */
#endif
#ifndef ICMP_UNREACH_NET_PROHIB
#define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */
#endif
#ifndef ICMP_UNREACH_HOST_PROHIB
#define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */
#endif
#ifndef ICMP_UNREACH_TOSNET
#define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */
#endif
#ifndef ICMP_UNREACH_TOSHOST
#define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */
#endif
/* rfc1716 */
#ifndef ICMP_UNREACH_FILTER_PROHIB
#define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */
#endif
#ifndef ICMP_UNREACH_HOST_PRECEDENCE
#define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */
#endif
#ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF
#define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */
#endif
/* rfc1256 */
#ifndef ICMP_ROUTERADVERT
#define ICMP_ROUTERADVERT 9 /* router advertisement */
#endif
#ifndef ICMP_ROUTERSOLICIT
#define ICMP_ROUTERSOLICIT 10 /* router solicitation */
#endif
#define ICMP_INFOTYPE(type) \
((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
(type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
(type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
(type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
(type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
/* Most of the icmp types */
static struct tok icmp2str[] = {
{ ICMP_ECHOREPLY, "echo reply" },
{ ICMP_SOURCEQUENCH, "source quench" },
{ ICMP_ECHO, "echo request" },
{ ICMP_ROUTERSOLICIT, "router solicitation" },
{ ICMP_TSTAMP, "time stamp request" },
{ ICMP_TSTAMPREPLY, "time stamp reply" },
{ ICMP_IREQ, "information request" },
{ ICMP_IREQREPLY, "information reply" },
{ ICMP_MASKREQ, "address mask request" },
{ 0, NULL }
};
/* Formats for most of the ICMP_UNREACH codes */
static struct tok unreach2str[] = {
{ ICMP_UNREACH_NET, "net %s unreachable" },
{ ICMP_UNREACH_HOST, "host %s unreachable" },
{ ICMP_UNREACH_SRCFAIL,
"%s unreachable - source route failed" },
{ ICMP_UNREACH_NET_UNKNOWN, "net %s unreachable - unknown" },
{ ICMP_UNREACH_HOST_UNKNOWN, "host %s unreachable - unknown" },
{ ICMP_UNREACH_ISOLATED,
"%s unreachable - source host isolated" },
{ ICMP_UNREACH_NET_PROHIB,
"net %s unreachable - admin prohibited" },
{ ICMP_UNREACH_HOST_PROHIB,
"host %s unreachable - admin prohibited" },
{ ICMP_UNREACH_TOSNET,
"net %s unreachable - tos prohibited" },
{ ICMP_UNREACH_TOSHOST,
"host %s unreachable - tos prohibited" },
{ ICMP_UNREACH_FILTER_PROHIB,
"host %s unreachable - admin prohibited filter" },
{ ICMP_UNREACH_HOST_PRECEDENCE,
"host %s unreachable - host precedence violation" },
{ ICMP_UNREACH_PRECEDENCE_CUTOFF,
"host %s unreachable - precedence cutoff" },
{ 0, NULL }
};
/* Formats for the ICMP_REDIRECT codes */
static struct tok type2str[] = {
{ ICMP_REDIRECT_NET, "redirect %s to net %s" },
{ ICMP_REDIRECT_HOST, "redirect %s to host %s" },
{ ICMP_REDIRECT_TOSNET, "redirect-tos %s to net %s" },
{ ICMP_REDIRECT_TOSHOST, "redirect-tos %s to net %s" },
{ 0, NULL }
};
/* rfc1191 */
struct mtu_discovery {
short unused;
short nexthopmtu;
};
/* rfc1256 */
struct ih_rdiscovery {
u_char ird_addrnum;
u_char ird_addrsiz;
u_short ird_lifetime;
};
struct id_rdiscovery {
u_int32_t ird_addr;
u_int32_t ird_pref;
};
void
icmp_print(const u_char *bp, u_int length, const u_char *bp2)
{
const struct icmp *dp;
const struct ip *ip;
const char *str, *fmt;
const struct ip *oip;
const struct udphdr *ouh;
u_int hlen, dport, mtu;
char buf[HOST_NAME_MAX+1+256];
char buf2[HOST_NAME_MAX+1+256];
dp = (struct icmp *)bp;
ip = (struct ip *)bp2;
str = buf;
(void)printf("%s > %s: ",
ipaddr_string(&ip->ip_src),
ipaddr_string(&ip->ip_dst));
TCHECK(dp->icmp_code);
if (qflag)
(void) snprintf(buf, sizeof buf, "%u %u", dp->icmp_type,
dp->icmp_code);
else switch (dp->icmp_type) {
case ICMP_ECHOREPLY:
case ICMP_ECHO:
if (vflag) {
TCHECK(dp->icmp_seq);
(void)snprintf(buf, sizeof buf,
"echo %s (id:%04x seq:%u)",
(dp->icmp_type == ICMP_ECHO)?
"request": "reply",
ntohs(dp->icmp_id),
ntohs(dp->icmp_seq));
} else
str = tok2str(icmp2str, "type-#%u", dp->icmp_type);
break;
case ICMP_UNREACH:
TCHECK(dp->icmp_ip.ip_dst);
switch (dp->icmp_code) {
case ICMP_UNREACH_PROTOCOL:
TCHECK(dp->icmp_ip.ip_p);
(void)snprintf(buf, sizeof buf,
"%s protocol %u unreachable",
ipaddr_string(&dp->icmp_ip.ip_dst),
dp->icmp_ip.ip_p);
break;
case ICMP_UNREACH_PORT:
TCHECK(dp->icmp_ip.ip_p);
oip = &dp->icmp_ip;
hlen = oip->ip_hl * 4;
ouh = (struct udphdr *)(((u_char *)oip) + hlen);
TCHECK(ouh->uh_dport);
dport = ntohs(ouh->uh_dport);
switch (oip->ip_p) {
case IPPROTO_TCP:
(void)snprintf(buf, sizeof buf,
"%s tcp port %s unreachable",
ipaddr_string(&oip->ip_dst),
tcpport_string(dport));
break;
case IPPROTO_UDP:
(void)snprintf(buf, sizeof buf,
"%s udp port %s unreachable",
ipaddr_string(&oip->ip_dst),
udpport_string(dport));
break;
default:
(void)snprintf(buf, sizeof buf,
"%s protocol %u port %u unreachable",
ipaddr_string(&oip->ip_dst),
oip->ip_p, dport);
break;
}
break;
case ICMP_UNREACH_NEEDFRAG:
{
const struct mtu_discovery *mp;
mp = (struct mtu_discovery *)&dp->icmp_void;
mtu = EXTRACT_16BITS(&mp->nexthopmtu);
if (mtu)
(void)snprintf(buf, sizeof buf,
"%s unreachable - need to frag (mtu %u)",
ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
else
(void)snprintf(buf, sizeof buf,
"%s unreachable - need to frag",
ipaddr_string(&dp->icmp_ip.ip_dst));
}
break;
default:
fmt = tok2str(unreach2str, "#%u %%s unreachable",
dp->icmp_code);
(void)snprintf(buf, sizeof buf, fmt,
ipaddr_string(&dp->icmp_ip.ip_dst));
break;
}
break;
case ICMP_REDIRECT:
TCHECK(dp->icmp_ip.ip_dst);
fmt = tok2str(type2str, "redirect-#%u %%s to net %%s",
dp->icmp_code);
(void)snprintf(buf, sizeof buf, fmt,
ipaddr_string(&dp->icmp_ip.ip_dst),
ipaddr_string(&dp->icmp_gwaddr));
break;
case ICMP_ROUTERADVERT:
{
const struct ih_rdiscovery *ihp;
const struct id_rdiscovery *idp;
u_int lifetime, num, size;
(void)strlcpy(buf, "router advertisement", sizeof(buf));
ihp = (struct ih_rdiscovery *)&dp->icmp_void;
TCHECK(*ihp);
(void)strlcat(buf, " lifetime ", sizeof(buf));
lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
if (lifetime < 60)
(void)snprintf(buf2, sizeof(buf2), "%u", lifetime);
else if (lifetime < 60 * 60)
(void)snprintf(buf2, sizeof(buf2), "%u:%02u",
lifetime / 60, lifetime % 60);
else
(void)snprintf(buf2, sizeof(buf2), "%u:%02u:%02u",
lifetime / 3600, (lifetime % 3600) / 60,
lifetime % 60);
strlcat(buf, buf2, sizeof(buf));
num = ihp->ird_addrnum;
(void)snprintf(buf2, sizeof(buf2), " %u:", num);
strlcat(buf, buf2, sizeof(buf));
size = ihp->ird_addrsiz;
if (size != 2) {
(void)snprintf(buf2, sizeof(buf2), " [size %u]", size);
strlcat(buf, buf2, sizeof(buf));
break;
}
idp = (struct id_rdiscovery *)&dp->icmp_data;
while (num-- > 0) {
TCHECK(*idp);
(void)snprintf(buf2, sizeof(buf2), " {%s %u}",
ipaddr_string(&idp->ird_addr),
EXTRACT_32BITS(&idp->ird_pref));
strlcat(buf, buf2, sizeof(buf));
}
}
break;
case ICMP_TIMXCEED:
TCHECK(dp->icmp_ip.ip_dst);
switch (dp->icmp_code) {
case ICMP_TIMXCEED_INTRANS:
str = "time exceeded in-transit";
break;
case ICMP_TIMXCEED_REASS:
str = "ip reassembly time exceeded";
break;
default:
(void)snprintf(buf, sizeof buf,
"time exceeded-#%u", dp->icmp_code);
break;
}
break;
case ICMP_PARAMPROB:
switch (dp->icmp_code) {
case ICMP_PARAMPROB_OPTABSENT:
str = "requested option absent";
break;
case ICMP_PARAMPROB_LENGTH:
snprintf(buf, sizeof buf, "bad length %u", dp->icmp_pptr);
break;
default:
TCHECK(dp->icmp_pptr);
(void)snprintf(buf, sizeof buf,
"parameter problem - octet %u",
dp->icmp_pptr);
break;
}
break;
case ICMP_MASKREPLY:
TCHECK(dp->icmp_mask);
(void)snprintf(buf, sizeof buf, "address mask is 0x%08x",
(u_int32_t)ntohl(dp->icmp_mask));
break;
default:
str = tok2str(icmp2str, "type-#%u", dp->icmp_type);
break;
}
(void)printf("icmp: %s", str);
if (vflag) {
if (TTEST2(dp->icmp_type, length)) {
u_int16_t sum, icmp_sum;
sum = in_cksum((const u_short *)dp, length, 0);
if (sum != 0) {
icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
(void)printf(" [bad icmp cksum %x! -> %x]", icmp_sum,
in_cksum_shouldbe(icmp_sum, sum));
}
else
(void)printf(" [icmp cksum ok]");
}
}
if (vflag > 1 && !ICMP_INFOTYPE(dp->icmp_type) &&
TTEST(dp->icmp_ip)) {
(void)printf(" for ");
oip = &dp->icmp_ip;
ip_print((u_char *)oip, ntohs(oip->ip_len));
}
return;
trunc:
fputs("[|icmp]", stdout);
}
|
