#ifndef lint
static const char rcsid[] =
- "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.56 1999-10-17 21:37:16 mcr Exp $ (LBL)";
+ "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.81 2000-12-23 20:55:22 guy Exp $ (LBL)";
+#endif
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
#endif
#include <sys/param.h>
#include <sys/time.h>
-#define __FAVOR_BSD
+#include <rpc/rpc.h>
#include <netinet/in.h>
-#include <netinet/in_systm.h>
-#include <netinet/ip.h>
-#include <netinet/tcp.h>
-#ifdef HAVE_MEMORY_H
-#include <memory.h>
-#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <ctype.h>
#include <unistd.h>
#include "interface.h"
#include "addrtoname.h"
#include "extract.h"
+#include "tcp.h"
+
+#include "ip.h"
+#ifdef INET6
+#include "ip6.h"
+#endif
+
+static void print_tcp_rst_data(register const u_char *sp, u_int length);
+
+#define MAX_RST_DATA_LEN 30
+
/* Compatibility */
#ifndef TCPOPT_WSCALE
#define TCPOPT_WSCALE 3 /* window scale factor (rfc1072) */
#define TCPOPT_CCECHO 13 /* T/TCP CC options (rfc1644) */
#endif
+/*
+ * Definitions required for ECN
+ * for use if the OS running tcpdump does not have ECN
+ */
+#ifndef TH_ECNECHO
+#define TH_ECNECHO 0x40 /* ECN Echo in tcp header */
+#endif
+#ifndef TH_CWR
+#define TH_CWR 0x80 /* ECN Cwnd Reduced in tcp header*/
+#endif
+
struct tha {
+#ifndef INET6
struct in_addr src;
struct in_addr dst;
+#else
+ struct in6_addr src;
+ struct in6_addr dst;
+#endif /*INET6*/
u_int port;
};
static struct tcp_seq_hash tcp_seq_hash[TSEQ_HASHSIZE];
+#ifndef TELNET_PORT
+#define TELNET_PORT 23
+#endif
+#ifndef BGP_PORT
+#define BGP_PORT 179
+#endif
+#define NETBIOS_SSN_PORT 139
+#define BXXP_PORT 10288
+#ifndef NFS_PORT
+#define NFS_PORT 2049
+#endif
+
+static int tcp_cksum(register const struct ip *ip,
+ register const struct tcphdr *tp,
+ register int len)
+{
+ int i, tlen;
+ union phu {
+ struct phdr {
+ u_int32_t src;
+ u_int32_t dst;
+ u_char mbz;
+ u_char proto;
+ u_int16_t len;
+ } ph;
+ u_int16_t pa[6];
+ } phu;
+ register const u_int16_t *sp;
+ u_int32_t sum;
+ tlen = ntohs(ip->ip_len) - ((const char *)tp-(const char*)ip);
+
+ /* pseudo-header.. */
+ phu.ph.len = htons(tlen);
+ phu.ph.mbz = 0;
+ phu.ph.proto = IPPROTO_TCP;
+ memcpy(&phu.ph.src, &ip->ip_src.s_addr, sizeof(u_int32_t));
+ memcpy(&phu.ph.dst, &ip->ip_dst.s_addr, sizeof(u_int32_t));
+
+ sp = &phu.pa[0];
+ sum = sp[0]+sp[1]+sp[2]+sp[3]+sp[4]+sp[5];
+
+ sp = (const u_int16_t *)tp;
+
+ for (i=0; i<(tlen&~1); i+= 2)
+ sum += *sp++;
+
+ if (tlen & 1) {
+ sum += htons( (*(const u_int8_t *)sp) << 8);
+ }
+
+ while (sum > 0xffff)
+ sum = (sum & 0xffff) + (sum >> 16);
+ sum = ~sum & 0xffff;
+
+ return (sum);
+}
+
+#ifdef INET6
+static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp,
+ int len)
+{
+ int i, tlen;
+ register const u_int16_t *sp;
+ u_int32_t sum;
+ union {
+ struct {
+ struct in6_addr ph_src;
+ struct in6_addr ph_dst;
+ u_int32_t ph_len;
+ u_int8_t ph_zero[3];
+ u_int8_t ph_nxt;
+ } ph;
+ u_int16_t pa[20];
+ } phu;
+
+ tlen = ntohs(ip6->ip6_plen) + sizeof(struct ip6_hdr) -
+ ((const char *)tp - (const char*)ip6);
+
+ /* pseudo-header */
+ memset(&phu, 0, sizeof(phu));
+ phu.ph.ph_src = ip6->ip6_src;
+ phu.ph.ph_dst = ip6->ip6_dst;
+ phu.ph.ph_len = htonl(tlen);
+ phu.ph.ph_nxt = IPPROTO_TCP;
+
+ sum = 0;
+ for (i = 0; i < sizeof(phu.pa) / sizeof(phu.pa[0]); i++)
+ sum += phu.pa[i];
+
+ sp = (const u_int16_t *)tp;
+
+ for (i = 0; i < (tlen & ~1); i += 2)
+ sum += *sp++;
+
+ if (tlen & 1)
+ sum += htons((*(const u_int8_t *)sp) << 8);
+
+ while (sum > 0xffff)
+ sum = (sum & 0xffff) + (sum >> 16);
+ sum = ~sum & 0xffff;
+
+ return (sum);
+}
+#endif
+
void
tcp_print(register const u_char *bp, register u_int length,
- register const u_char *bp2)
+ register const u_char *bp2, int fragmented)
{
register const struct tcphdr *tp;
register const struct ip *ip;
register u_char flags;
register int hlen;
register char ch;
- u_short sport, dport, win, urp;
- u_int32_t seq, ack;
+ u_int16_t sport, dport, win, urp;
+ u_int32_t seq, ack, thseq, thack;
+ int threv;
+#ifdef INET6
+ register const struct ip6_hdr *ip6;
+#endif
tp = (struct tcphdr *)bp;
ip = (struct ip *)bp2;
+#ifdef INET6
+ if (IP_V(ip) == 6)
+ ip6 = (struct ip6_hdr *)bp2;
+ else
+ ip6 = NULL;
+#endif /*INET6*/
ch = '\0';
- TCHECK(*tp);
- if (length < sizeof(*tp)) {
- (void)printf("truncated-tcp %d", length);
+ if (!TTEST(tp->th_dport)) {
+ (void)printf("%s > %s: [|tcp]",
+ ipaddr_string(&ip->ip_src),
+ ipaddr_string(&ip->ip_dst));
return;
}
sport = ntohs(tp->th_sport);
dport = ntohs(tp->th_dport);
- seq = ntohl(tp->th_seq);
- ack = ntohl(tp->th_ack);
+
+
+ hlen = TH_OFF(tp) * 4;
+
+ /*
+ * If data present and NFS port used, assume NFS.
+ * Pass offset of data plus 4 bytes for RPC TCP msg length
+ * to NFS print routines.
+ */
+ if (!qflag) {
+ if ((u_char *)tp + 4 + sizeof(struct rpc_msg) <= snapend &&
+ dport == NFS_PORT) {
+ nfsreq_print((u_char *)tp + hlen + 4, length-hlen,
+ (u_char *)ip);
+ return;
+ } else if ((u_char *)tp + 4 + sizeof(struct rpc_msg)
+ <= snapend &&
+ sport == NFS_PORT) {
+ nfsreply_print((u_char *)tp + hlen + 4,length-hlen,
+ (u_char *)ip);
+ return;
+ }
+ }
+#ifdef INET6
+ if (ip6) {
+ if (ip6->ip6_nxt == IPPROTO_TCP) {
+ (void)printf("%s.%s > %s.%s: ",
+ ip6addr_string(&ip6->ip6_src),
+ tcpport_string(sport),
+ ip6addr_string(&ip6->ip6_dst),
+ tcpport_string(dport));
+ } else {
+ (void)printf("%s > %s: ",
+ tcpport_string(sport), tcpport_string(dport));
+ }
+ } else
+#endif /*INET6*/
+ {
+ if (ip->ip_p == IPPROTO_TCP) {
+ (void)printf("%s.%s > %s.%s: ",
+ ipaddr_string(&ip->ip_src),
+ tcpport_string(sport),
+ ipaddr_string(&ip->ip_dst),
+ tcpport_string(dport));
+ } else {
+ (void)printf("%s > %s: ",
+ tcpport_string(sport), tcpport_string(dport));
+ }
+ }
+
+ TCHECK(*tp);
+
+ seq = (u_int32_t)ntohl(tp->th_seq);
+ ack = (u_int32_t)ntohl(tp->th_ack);
win = ntohs(tp->th_win);
urp = ntohs(tp->th_urp);
- (void)printf("%s.%s > %s.%s: ",
- ipaddr_string(&ip->ip_src), tcpport_string(sport),
- ipaddr_string(&ip->ip_dst), tcpport_string(dport));
-
if (qflag) {
- (void)printf("tcp %d", length - tp->th_off * 4);
+ (void)printf("tcp %d", length - TH_OFF(tp) * 4);
return;
}
- if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH)) {
+ if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH|
+ TH_ECNECHO|TH_CWR)) {
if (flags & TH_SYN)
putchar('S');
if (flags & TH_FIN)
putchar('R');
if (flags & TH_PUSH)
putchar('P');
+ if (flags & TH_CWR)
+ putchar('W'); /* congestion _W_indow reduced (ECN) */
+ if (flags & TH_ECNECHO)
+ putchar('E'); /* ecn _E_cho sent (ECN) */
} else
putchar('.');
* collating order so there's only one entry for
* both directions).
*/
+#ifdef INET6
+ memset(&tha, 0, sizeof(tha));
+ rev = 0;
+ if (ip6) {
+ if (sport > dport) {
+ rev = 1;
+ } else if (sport == dport) {
+ int i;
+
+ for (i = 0; i < 4; i++) {
+ if (((u_int32_t *)(&ip6->ip6_src))[i] >
+ ((u_int32_t *)(&ip6->ip6_dst))[i]) {
+ rev = 1;
+ break;
+ }
+ }
+ }
+ if (rev) {
+ tha.src = ip6->ip6_dst;
+ tha.dst = ip6->ip6_src;
+ tha.port = dport << 16 | sport;
+ } else {
+ tha.dst = ip6->ip6_dst;
+ tha.src = ip6->ip6_src;
+ tha.port = sport << 16 | dport;
+ }
+ } else {
+ if (sport > dport ||
+ (sport == dport &&
+ ip->ip_src.s_addr > ip->ip_dst.s_addr)) {
+ rev = 1;
+ }
+ if (rev) {
+ *(struct in_addr *)&tha.src = ip->ip_dst;
+ *(struct in_addr *)&tha.dst = ip->ip_src;
+ tha.port = dport << 16 | sport;
+ } else {
+ *(struct in_addr *)&tha.dst = ip->ip_dst;
+ *(struct in_addr *)&tha.src = ip->ip_src;
+ tha.port = sport << 16 | dport;
+ }
+ }
+#else
if (sport < dport ||
(sport == dport &&
ip->ip_src.s_addr < ip->ip_dst.s_addr)) {
tha.port = dport << 16 | sport;
rev = 1;
}
+#endif
+ threv = rev;
for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
th->nxt; th = th->nxt)
if (!memcmp((char *)&tha, (char *)&th->addr,
sizeof(th->addr)))
break;
- if (!th->nxt || flags & TH_SYN) {
+ if (!th->nxt || (flags & TH_SYN)) {
/* didn't find it or new conversation */
if (th->nxt == NULL) {
th->nxt = (struct tcp_seq_hash *)
th->ack = seq, th->seq = ack - 1;
else
th->seq = seq, th->ack = ack - 1;
+
} else {
if (rev)
seq -= th->ack, ack -= th->seq;
else
seq -= th->seq, ack -= th->ack;
}
+
+ thseq = th->seq;
+ thack = th->ack;
+ } else {
+ /*fool gcc*/
+ thseq = thack = threv = 0;
}
- hlen = tp->th_off * 4;
if (hlen > length) {
(void)printf(" [bad hdr length]");
return;
}
+
+ if (IP_V(ip) == 4 && vflag && !fragmented) {
+ int sum;
+ if (TTEST2(tp->th_sport, length)) {
+ sum = tcp_cksum(ip, tp, length);
+ if (sum != 0)
+ (void)printf(" [bad tcp cksum %x!]", sum);
+ else
+ (void)printf(" [tcp sum ok]");
+ }
+ }
+#ifdef INET6
+ if (IP_V(ip) == 6 && ip6->ip6_plen && vflag && !fragmented) {
+ int sum;
+ if (TTEST2(tp->th_sport, length)) {
+ sum = tcp6_cksum(ip6, tp, length);
+ if (sum != 0)
+ (void)printf(" [bad tcp cksum %x!]", sum);
+ else
+ (void)printf(" [tcp sum ok]");
+ }
+ }
+#endif
+
length -= hlen;
- if (length > 0 || flags & (TH_SYN | TH_FIN | TH_RST))
+ if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST))
(void)printf(" %u:%u(%d)", seq, seq + length, length);
if (flags & TH_ACK)
(void)printf(" ack %u", ack);
case TCPOPT_SACK:
(void)printf("sack");
datalen = len - 2;
- for (i = 0; i < datalen; i += 4) {
- LENCHECK(i + 4);
- /* block-size@relative-origin */
- (void)printf(" %u@%u",
- EXTRACT_16BITS(cp + i + 2),
- EXTRACT_16BITS(cp + i));
+ if (datalen % 8 != 0) {
+ (void)printf(" malformed sack ");
+ } else {
+ u_int32_t s, e;
+
+ (void)printf(" sack %d ", datalen / 8);
+ for (i = 0; i < datalen; i += 8) {
+ LENCHECK(i + 4);
+ s = EXTRACT_32BITS(cp + i);
+ LENCHECK(i + 8);
+ e = EXTRACT_32BITS(cp + i + 4);
+ if (threv) {
+ s -= thseq;
+ e -= thseq;
+ } else {
+ s -= thack;
+ e -= thack;
+ }
+ (void)printf("{%u:%u}", s, e);
+ }
+ (void)printf(" ");
}
- if (datalen % 4)
- (void)printf("[len %d]", len);
break;
case TCPOPT_ECHO:
}
putchar('>');
}
+
+ if (length <= 0)
+ return;
+
+ /*
+ * Decode payload if necessary.
+ */
+ bp += TH_OFF(tp) * 4;
+ if (flags & TH_RST) {
+ if (vflag)
+ print_tcp_rst_data(bp, length);
+ } else {
+ if (sport == TELNET_PORT || dport == TELNET_PORT) {
+ if (!qflag && vflag)
+ telnet_print(bp, length);
+ } else if (sport == BGP_PORT || dport == BGP_PORT)
+ bgp_print(bp, length);
+ else if (sport == NETBIOS_SSN_PORT || dport == NETBIOS_SSN_PORT)
+ nbt_tcp_print(bp, length);
+ else if (sport == BXXP_PORT || dport == BXXP_PORT)
+ bxxp_print(bp, length);
+ }
return;
bad:
fputs("[bad opt]", stdout);
putchar('>');
}
+/*
+ * RFC1122 says the following on data in RST segments:
+ *
+ * 4.2.2.12 RST Segment: RFC-793 Section 3.4
+ *
+ * A TCP SHOULD allow a received RST segment to include data.
+ *
+ * DISCUSSION
+ * It has been suggested that a RST segment could contain
+ * ASCII text that encoded and explained the cause of the
+ * RST. No standard has yet been established for such
+ * data.
+ *
+ */
+
+static void
+print_tcp_rst_data(register const u_char *sp, u_int length)
+{
+ int c;
+
+ if (TTEST2(*sp, length))
+ printf(" [RST");
+ else
+ printf(" [!RST");
+ if (length > MAX_RST_DATA_LEN) {
+ length = MAX_RST_DATA_LEN; /* can use -X for longer */
+ putchar('+'); /* indicate we truncate */
+ }
+ putchar(' ');
+ while (length-- && sp <= snapend) {
+ c = *sp++;
+ if (isprint(c))
+ putchar(c);
+ else
+ putchar('.');
+ }
+ putchar(']');
+}
projects / tcpdump / blobdiff