print-tcp.c

Windump3.6.2源代码

/*
 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
 *	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.
 */

#ifndef lint
static const char rcsid[] =
    "@(#) $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

#ifndef WIN32
#include <sys/param.h>
#include <sys/time.h>

#include <rpc/rpc.h>

#include <netinet/in.h>
#else
#include <winsock2.h>
#include "bittypes.h"
#include "IP6_misc.h"
#include <time.h>
#include <rpc/rpc_cut.h>
#endif /* WIN32 */

#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
#ifndef WIN32
#include "ip6.h"
#endif /* WIN32 */
#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) */
#endif
#ifndef TCPOPT_SACKOK
#define	TCPOPT_SACKOK		4	/* selective ack ok (rfc1072) */
#endif
#ifndef TCPOPT_SACK
#define	TCPOPT_SACK		5	/* selective ack (rfc1072) */
#endif
#ifndef TCPOPT_ECHO
#define	TCPOPT_ECHO		6	/* echo (rfc1072) */
#endif
#ifndef TCPOPT_ECHOREPLY
#define	TCPOPT_ECHOREPLY	7	/* echo (rfc1072) */
#endif
#ifndef TCPOPT_TIMESTAMP
#define TCPOPT_TIMESTAMP	8	/* timestamps (rfc1323) */
#endif
#ifndef TCPOPT_CC
#define TCPOPT_CC		11	/* T/TCP CC options (rfc1644) */
#endif
#ifndef TCPOPT_CCNEW
#define TCPOPT_CCNEW		12	/* T/TCP CC options (rfc1644) */
#endif
#ifndef TCPOPT_CCECHO
#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;
};

struct tcp_seq_hash {
	struct tcp_seq_hash *nxt;
	struct tha addr;
	tcp_seq seq;
	tcp_seq ack;
};

#define TSEQ_HASHSIZE 919

/* These tcp optinos do not have the size octet */
#define ZEROLENOPT(o) ((o) == TCPOPT_EOL || (o) == TCPOPT_NOP)

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, int fragmented)
{
	register const struct tcphdr *tp;
	register const struct ip *ip;
	register u_char flags;
	register int hlen;
	register char ch;
	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';
	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);


	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);

	if (qflag) {
		(void)printf("tcp %d", length - TH_OFF(tp) * 4);
		return;
	}
	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('F');
		if (flags & TH_RST)
			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('.');

	if (!Sflag && (flags & TH_ACK)) {
		register struct tcp_seq_hash *th;
		register int rev;
		struct tha tha;
		/*
		 * Find (or record) the initial sequence numbers for
		 * this conversation.  (we pick an arbitrary
		 * collating order so there's only one entry for