X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/c9ce67cf66f986ac716e68083c62563d3af98e20..refs/heads/tcpdump-3.8:/print-icmp.c diff --git a/print-icmp.c b/print-icmp.c index 5895ce98..a8e21b0a 100644 --- a/print-icmp.c +++ b/print-icmp.c @@ -20,33 +20,15 @@ */ #ifndef lint -static const char rcsid[] = - "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.43 1999-11-22 04:28:21 fenner Exp $ (LBL)"; +static const char rcsid[] _U_ = + "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.73.2.3 2004-03-24 00:56:34 guy Exp $ (LBL)"; #endif #ifdef HAVE_CONFIG_H #include "config.h" #endif -#include -#include -#include - -#if __STDC__ -struct mbuf; -struct rtentry; -#endif -#include - -#include -#include -#include -#include -#include -#include -#include -#include -#include +#include #include #include @@ -55,6 +37,127 @@ struct rtentry; #include "addrtoname.h" #include "extract.h" /* must come after interface.h */ +#include "ip.h" +#include "udp.h" +#include "ipproto.h" + +/* + * Interface Control Message Protocol Definitions. + * Per RFC 792, September 1981. + */ + +/* + * Structure of an icmp header. + */ +struct icmp { + u_int8_t icmp_type; /* type of message, see below */ + u_int8_t icmp_code; /* type sub code */ + u_int16_t icmp_cksum; /* ones complement cksum of struct */ + union { + u_int8_t ih_pptr; /* ICMP_PARAMPROB */ + struct in_addr ih_gwaddr; /* ICMP_REDIRECT */ + struct ih_idseq { + u_int16_t icd_id; + u_int16_t icd_seq; + } ih_idseq; + u_int32_t ih_void; + + /* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */ + struct ih_pmtu { + u_int16_t ipm_void; + u_int16_t ipm_nextmtu; + } ih_pmtu; + } icmp_hun; +#define icmp_pptr icmp_hun.ih_pptr +#define icmp_gwaddr icmp_hun.ih_gwaddr +#define icmp_id icmp_hun.ih_idseq.icd_id +#define icmp_seq icmp_hun.ih_idseq.icd_seq +#define icmp_void icmp_hun.ih_void +#define icmp_pmvoid icmp_hun.ih_pmtu.ipm_void +#define icmp_nextmtu icmp_hun.ih_pmtu.ipm_nextmtu + union { + struct id_ts { + u_int32_t its_otime; + u_int32_t its_rtime; + u_int32_t its_ttime; + } id_ts; + struct id_ip { + struct ip idi_ip; + /* options and then 64 bits of data */ + } id_ip; + u_int32_t id_mask; + u_int8_t id_data[1]; + } icmp_dun; +#define icmp_otime icmp_dun.id_ts.its_otime +#define icmp_rtime icmp_dun.id_ts.its_rtime +#define icmp_ttime icmp_dun.id_ts.its_ttime +#define icmp_ip icmp_dun.id_ip.idi_ip +#define icmp_mask icmp_dun.id_mask +#define icmp_data icmp_dun.id_data +}; + +/* + * Lower bounds on packet lengths for various types. + * For the error advice packets must first insure that the + * packet is large enought to contain the returned ip header. + * Only then can we do the check to see if 64 bits of packet + * data have been returned, since we need to check the returned + * ip header length. + */ +#define ICMP_MINLEN 8 /* abs minimum */ +#define ICMP_TSLEN (8 + 3 * sizeof (u_int32_t)) /* timestamp */ +#define ICMP_MASKLEN 12 /* address mask */ +#define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */ +#define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8) + /* N.B.: must separately check that ip_hl >= 5 */ + +/* + * Definition of type and code field values. + */ +#define ICMP_ECHOREPLY 0 /* echo reply */ +#define ICMP_UNREACH 3 /* dest unreachable, codes: */ +#define ICMP_UNREACH_NET 0 /* bad net */ +#define ICMP_UNREACH_HOST 1 /* bad host */ +#define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */ +#define ICMP_UNREACH_PORT 3 /* bad port */ +#define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */ +#define ICMP_UNREACH_SRCFAIL 5 /* src route failed */ +#define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */ +#define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */ +#define ICMP_UNREACH_ISOLATED 8 /* src host isolated */ +#define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */ +#define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */ +#define ICMP_UNREACH_TOSNET 11 /* bad tos for net */ +#define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */ +#define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */ +#define ICMP_REDIRECT 5 /* shorter route, codes: */ +#define ICMP_REDIRECT_NET 0 /* for network */ +#define ICMP_REDIRECT_HOST 1 /* for host */ +#define ICMP_REDIRECT_TOSNET 2 /* for tos and net */ +#define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */ +#define ICMP_ECHO 8 /* echo service */ +#define ICMP_ROUTERADVERT 9 /* router advertisement */ +#define ICMP_ROUTERSOLICIT 10 /* router solicitation */ +#define ICMP_TIMXCEED 11 /* time exceeded, code: */ +#define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */ +#define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */ +#define ICMP_PARAMPROB 12 /* ip header bad */ +#define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */ +#define ICMP_TSTAMP 13 /* timestamp request */ +#define ICMP_TSTAMPREPLY 14 /* timestamp reply */ +#define ICMP_IREQ 15 /* information request */ +#define ICMP_IREQREPLY 16 /* information reply */ +#define ICMP_MASKREQ 17 /* address mask request */ +#define ICMP_MASKREPLY 18 /* address mask reply */ + +#define ICMP_MAXTYPE 18 + +#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) /* rfc1700 */ #ifndef ICMP_UNREACH_NET_UNKNOWN #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */ @@ -89,14 +192,6 @@ struct rtentry; #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 - /* Most of the icmp types */ static struct tok icmp2str[] = { { ICMP_ECHOREPLY, "echo reply" }, @@ -143,21 +238,21 @@ 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" }, + { ICMP_REDIRECT_TOSHOST, "redirect-tos %s to host %s" }, { 0, NULL } }; /* rfc1191 */ struct mtu_discovery { - short unused; - short nexthopmtu; + u_int16_t unused; + u_int16_t nexthopmtu; }; /* rfc1256 */ struct ih_rdiscovery { - u_char ird_addrnum; - u_char ird_addrsiz; - u_short ird_lifetime; + u_int8_t ird_addrnum; + u_int8_t ird_addrsiz; + u_int16_t ird_lifetime; }; struct id_rdiscovery { @@ -166,65 +261,70 @@ struct id_rdiscovery { }; void -icmp_print(register const u_char *bp, u_int plen, register const u_char *bp2) +icmp_print(const u_char *bp, u_int plen, const u_char *bp2, int fragmented) { - register char *cp; - register const struct icmp *dp; - register const struct ip *ip; - register const char *str, *fmt; - register const struct ip *oip; - register const struct udphdr *ouh; - register u_int hlen, dport, mtu; - char buf[256]; + char *cp; + 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[MAXHOSTNAMELEN + 100]; dp = (struct icmp *)bp; ip = (struct ip *)bp2; str = buf; -#if 0 - (void)printf("%s > %s: ", - ipaddr_string(&ip->ip_src), - ipaddr_string(&ip->ip_dst)); -#endif - TCHECK(dp->icmp_code); switch (dp->icmp_type) { + case ICMP_ECHO: + case ICMP_ECHOREPLY: + TCHECK(dp->icmp_seq); + (void)snprintf(buf, sizeof(buf), "echo %s seq %u", + dp->icmp_type == ICMP_ECHO ? + "request" : "reply", + EXTRACT_16BITS(&dp->icmp_seq)); + 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)sprintf(buf, "%s protocol %d unreachable", - ipaddr_string(&dp->icmp_ip.ip_dst), - dp->icmp_ip.ip_p); + (void)snprintf(buf, sizeof(buf), + "%s protocol %d 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; + hlen = IP_HL(oip) * 4; ouh = (struct udphdr *)(((u_char *)oip) + hlen); - dport = ntohs(ouh->uh_dport); + TCHECK(ouh->uh_dport); + dport = EXTRACT_16BITS(&ouh->uh_dport); switch (oip->ip_p) { case IPPROTO_TCP: - (void)sprintf(buf, + (void)snprintf(buf, sizeof(buf), "%s tcp port %s unreachable", ipaddr_string(&oip->ip_dst), tcpport_string(dport)); break; case IPPROTO_UDP: - (void)sprintf(buf, + (void)snprintf(buf, sizeof(buf), "%s udp port %s unreachable", ipaddr_string(&oip->ip_dst), udpport_string(dport)); break; default: - (void)sprintf(buf, + (void)snprintf(buf, sizeof(buf), "%s protocol %d port %d unreachable", ipaddr_string(&oip->ip_dst), oip->ip_p, dport); @@ -233,26 +333,26 @@ icmp_print(register const u_char *bp, u_int plen, register const u_char *bp2) break; case ICMP_UNREACH_NEEDFRAG: - { + { register const struct mtu_discovery *mp; - mp = (struct mtu_discovery *)&dp->icmp_void; - mtu = EXTRACT_16BITS(&mp->nexthopmtu); - if (mtu) - (void)sprintf(buf, - "%s unreachable - need to frag (mtu %d)", - ipaddr_string(&dp->icmp_ip.ip_dst), mtu); - else - (void)sprintf(buf, - "%s unreachable - need to frag", - ipaddr_string(&dp->icmp_ip.ip_dst)); + mtu = EXTRACT_16BITS(&mp->nexthopmtu); + if (mtu) { + (void)snprintf(buf, sizeof(buf), + "%s unreachable - need to frag (mtu %d)", + 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, "#%d %%s unreachable", dp->icmp_code); - (void)sprintf(buf, fmt, + (void)snprintf(buf, sizeof(buf), fmt, ipaddr_string(&dp->icmp_ip.ip_dst)); break; } @@ -262,55 +362,60 @@ icmp_print(register const u_char *bp, u_int plen, register const u_char *bp2) TCHECK(dp->icmp_ip.ip_dst); fmt = tok2str(type2str, "redirect-#%d %%s to net %%s", dp->icmp_code); - (void)sprintf(buf, fmt, + (void)snprintf(buf, sizeof(buf), fmt, ipaddr_string(&dp->icmp_ip.ip_dst), ipaddr_string(&dp->icmp_gwaddr)); break; case ICMP_ROUTERADVERT: - { + { register const struct ih_rdiscovery *ihp; register const struct id_rdiscovery *idp; u_int lifetime, num, size; - (void)strcpy(buf, "router advertisement"); + (void)snprintf(buf, sizeof(buf), "router advertisement"); cp = buf + strlen(buf); ihp = (struct ih_rdiscovery *)&dp->icmp_void; TCHECK(*ihp); - (void)strcpy(cp, " lifetime "); + (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf)); cp = buf + strlen(buf); lifetime = EXTRACT_16BITS(&ihp->ird_lifetime); - if (lifetime < 60) - (void)sprintf(cp, "%u", lifetime); - else if (lifetime < 60 * 60) - (void)sprintf(cp, "%u:%02u", + if (lifetime < 60) { + (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u", + lifetime); + } else if (lifetime < 60 * 60) { + (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u", lifetime / 60, lifetime % 60); - else - (void)sprintf(cp, "%u:%02u:%02u", + } else { + (void)snprintf(cp, sizeof(buf) - (cp - buf), + "%u:%02u:%02u", lifetime / 3600, (lifetime % 3600) / 60, lifetime % 60); + } cp = buf + strlen(buf); num = ihp->ird_addrnum; - (void)sprintf(cp, " %d:", num); + (void)snprintf(cp, sizeof(buf) - (cp - buf), " %d:", num); cp = buf + strlen(buf); size = ihp->ird_addrsiz; if (size != 2) { - (void)sprintf(cp, " [size %d]", size); + (void)snprintf(cp, sizeof(buf) - (cp - buf), + " [size %d]", size); break; } idp = (struct id_rdiscovery *)&dp->icmp_data; while (num-- > 0) { TCHECK(*idp); - (void)sprintf(cp, " {%s %u}", + (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}", ipaddr_string(&idp->ird_addr), EXTRACT_32BITS(&idp->ird_pref)); cp = buf + strlen(buf); + ++idp; } - } + } break; case ICMP_TIMXCEED: @@ -326,46 +431,72 @@ icmp_print(register const u_char *bp, u_int plen, register const u_char *bp2) break; default: - (void)sprintf(buf, "time exceeded-#%d", dp->icmp_code); + (void)snprintf(buf, sizeof(buf), "time exceeded-#%d", + dp->icmp_code); break; } break; case ICMP_PARAMPROB: if (dp->icmp_code) - (void)sprintf(buf, "parameter problem - code %d", - dp->icmp_code); + (void)snprintf(buf, sizeof(buf), + "parameter problem - code %d", dp->icmp_code); else { TCHECK(dp->icmp_pptr); - (void)sprintf(buf, "parameter problem - octet %d", - dp->icmp_pptr); + (void)snprintf(buf, sizeof(buf), + "parameter problem - octet %d", dp->icmp_pptr); } break; case ICMP_MASKREPLY: TCHECK(dp->icmp_mask); - (void)sprintf(buf, "address mask is 0x%08x", - (u_int32_t)ntohl(dp->icmp_mask)); + (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x", + EXTRACT_32BITS(&dp->icmp_mask)); + break; + + case ICMP_TSTAMP: + TCHECK(dp->icmp_seq); + (void)snprintf(buf, sizeof(buf), + "time stamp query id %u seq %u", + EXTRACT_16BITS(&dp->icmp_id), + EXTRACT_16BITS(&dp->icmp_seq)); + break; + + case ICMP_TSTAMPREPLY: + TCHECK(dp->icmp_ttime); + (void)snprintf(buf, sizeof(buf), + "time stamp reply id %u seq %u : org 0x%x recv 0x%x xmit 0x%x", + EXTRACT_16BITS(&dp->icmp_id), + EXTRACT_16BITS(&dp->icmp_seq), + EXTRACT_32BITS(&dp->icmp_otime), + EXTRACT_32BITS(&dp->icmp_rtime), + EXTRACT_32BITS(&dp->icmp_ttime)); break; default: str = tok2str(icmp2str, "type-#%d", dp->icmp_type); break; } - (void)printf("icmp: %s", str); - if (vflag) { + (void)printf("icmp %d: %s", plen, str); + if (vflag && !fragmented) { /* don't attempt checksumming if this is a frag */ + u_int16_t sum, icmp_sum; if (TTEST2(*bp, plen)) { - if (in_cksum((u_short*)dp, plen, 0)) - printf(" (wrong icmp csum)"); + sum = in_cksum((u_short*)dp, plen, 0); + if (sum != 0) { + icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum); + (void)printf(" (wrong icmp cksum %x (->%x)!)", + icmp_sum, + in_cksum_shouldbe(icmp_sum, sum)); + } } } - if (vflag > 1 && !ICMP_INFOTYPE(dp->icmp_type)) { - bp += 8; - (void)printf(" for "); - ip = (struct ip *)bp; - snaplen = snapend - bp; - ip_print(bp, ntohs(ip->ip_len)); - } + if (vflag > 1 && !ICMP_INFOTYPE(dp->icmp_type)) { + bp += 8; + (void)printf(" for "); + ip = (struct ip *)bp; + snaplen = snapend - bp; + ip_print(bp, EXTRACT_16BITS(&ip->ip_len)); + } return; trunc: fputs("[|icmp]", stdout);