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/* $NetBSD: print-tcp.c,v 1.5 1995/03/06 19:11:33 mycroft Exp $ */
/*
* Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
* 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 char rcsid[] =
"@(#) Header: print-tcp.c,v 1.28 94/06/16 01:26:40 mccanne Exp (LBL)";
#endif
#include <sys/param.h>
#include <sys/time.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcpip.h>
#include <stdio.h>
#ifdef __STDC__
#include <stdlib.h>
#endif
#include <unistd.h>
#include "interface.h"
#include "addrtoname.h"
#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
struct tha {
struct in_addr src;
struct in_addr dst;
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
static struct tcp_seq_hash tcp_seq_hash[TSEQ_HASHSIZE];
void
tcp_print(register const u_char *bp, register int length,
register const u_char *bp2)
{
register const struct tcphdr *tp;
register const struct ip *ip;
register u_char flags;
register int hlen;
u_short sport, dport, win, urp;
tcp_seq seq, ack;
tp = (struct tcphdr *)bp;
ip = (struct ip *)bp2;
if ((const u_char *)(tp + 1) > snapend) {
printf("[|tcp]");
return;
}
if (length < sizeof(struct tcphdr)) {
(void)printf("truncated-tcp %d", length);
return;
}
sport = ntohs(tp->th_sport);
dport = ntohs(tp->th_dport);
seq = ntohl(tp->th_seq);
ack = 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);
return;
}
if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH)) {
if (flags & TH_SYN)
putchar('S');
if (flags & TH_FIN)
putchar('F');
if (flags & TH_RST)
putchar('R');
if (flags & TH_PUSH)
putchar('P');
} 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
* both directions).
*/
if (sport < dport ||
(sport == dport &&
ip->ip_src.s_addr < ip->ip_dst.s_addr)) {
tha.src = ip->ip_src, tha.dst = ip->ip_dst;
tha.port = sport << 16 | dport;
rev = 0;
} else {
tha.src = ip->ip_dst, tha.dst = ip->ip_src;
tha.port = dport << 16 | sport;
rev = 1;
}
for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
th->nxt; th = th->nxt)
if (!bcmp((char *)&tha, (char *)&th->addr,
sizeof(th->addr)))
break;
if (!th->nxt || flags & TH_SYN) {
/* didn't find it or new conversation */
if (!th->nxt)
th->nxt = (struct tcp_seq_hash *)
calloc(1, sizeof (*th));
th->addr = tha;
if (rev)
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;
}
}
hlen = tp->th_off * 4;
length -= hlen;
if (length > 0 || flags & (TH_SYN | TH_FIN | TH_RST))
(void)printf(" %lu:%lu(%d)", seq, seq + length, length);
if (flags & TH_ACK)
(void)printf(" ack %u", ack);
(void)printf(" win %d", win);
if (flags & TH_URG)
(void)printf(" urg %d", urp);
/*
* Handle any options.
*/
if ((hlen -= sizeof(struct tcphdr)) > 0) {
register const u_char *cp = (const u_char *)tp + sizeof(*tp);
int i;
char ch = '<';
putchar(' ');
while (--hlen >= 0) {
putchar(ch);
switch (*cp++) {
case TCPOPT_MAXSEG:
{
(void)printf("mss %d", cp[1] << 8 | cp[2]);
if (*cp != 4)
(void)printf("[len %d]", *cp);
cp += 3;
hlen -= 3;
break;
}
case TCPOPT_EOL:
(void)printf("eol");
break;
case TCPOPT_NOP:
(void)printf("nop");
break;
case TCPOPT_WSCALE:
(void)printf("wscale %d", cp[1]);
if (*cp != 3)
(void)printf("[len %d]", *cp);
cp += 2;
hlen -= 2;
break;
case TCPOPT_SACKOK:
(void)printf("sackOK");
if (*cp != 2)
(void)printf("[len %d]", *cp);
cp += 1;
hlen -= 1;
break;
case TCPOPT_ECHO:
{
(void)printf("echo %u",
cp[1] << 24 | cp[2] << 16 |
cp[3] << 8 | cp[4]);
if (*cp != 6)
(void)printf("[len %d]", *cp);
cp += 5;
hlen -= 5;
break;
}
case TCPOPT_ECHOREPLY:
{
(void)printf("echoreply %u",
cp[1] << 24 | cp[2] << 16 |
cp[3] << 8 | cp[4]);
if (*cp != 6)
(void)printf("[len %d]", *cp);
cp += 5;
hlen -= 5;
break;
}
case TCPOPT_TIMESTAMP:
{
(void)printf("timestamp %lu %lu",
cp[1] << 24 | cp[2] << 16 |
cp[3] << 8 | cp[4],
cp[5] << 24 | cp[6] << 16 |
cp[7] << 8 | cp[8]);
if (*cp != 10)
(void)printf("[len %d]", *cp);
cp += 9;
hlen -= 9;
break;
}
default:
(void)printf("opt-%d:", cp[-1]);
for (i = *cp++ - 2, hlen -= i + 1; i > 0; --i)
(void)printf("%02x", *cp++);
break;
}
ch = ',';
}
putchar('>');
}
}
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