/*

* Copyright (c) 1989, 1990, 1991, 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.

*/

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <tcpdump-stdinc.h>

#include "interface.h"

#include "extract.h" /* must come after interface.h */

#include "ip.h"

#include "tcp.h"

#include "slcompress.h"

/*

* definitions of the pseudo- link-level header attached to slip

* packets grabbed by the packet filter (bpf) traffic monitor.

*/

#define SLIP_HDRLEN 16

#define SLX_DIR 0

#define SLX_CHDR 1

#define CHDR_LEN 15

#define SLIPDIR_IN 0

#define SLIPDIR_OUT 1

static const char tstr[] = "[|slip]";

static u_int lastlen[2][256];

static u_int lastconn = 255;

static void sliplink_print(netdissect_options *, const u_char *, const struct ip *, u_int);

static void compressed_sl_print(netdissect_options *, const u_char *, const struct ip *, u_int, int);

u_int

sl_if_print(netdissect_options *ndo,

const struct pcap_pkthdr *h, const u_char *p)

{

register u_int caplen = h->caplen;

register u_int length = h->len;

register const struct ip *ip;

if (caplen < SLIP_HDRLEN || length < SLIP_HDRLEN) {

ND_PRINT((ndo, "%s", tstr));

return (caplen);

}

length -= SLIP_HDRLEN;

ip = (struct ip *)(p + SLIP_HDRLEN);

if (ndo->ndo_eflag)

sliplink_print(ndo, p, ip, length);

switch (IP_V(ip)) {

case 4:

ip_print(ndo, (u_char *)ip, length);

break;

case 6:

ip6_print(ndo, (u_char *)ip, length);

break;

default:

ND_PRINT((ndo, "ip v%d", IP_V(ip)));

}

return (SLIP_HDRLEN);

}

u_int

sl_bsdos_if_print(netdissect_options *ndo,

const struct pcap_pkthdr *h, const u_char *p)

{

register u_int caplen = h->caplen;

register u_int length = h->len;

register const struct ip *ip;

if (caplen < SLIP_HDRLEN) {

ND_PRINT((ndo, "%s", tstr));

return (caplen);

}

length -= SLIP_HDRLEN;

ip = (struct ip *)(p + SLIP_HDRLEN);

#ifdef notdef

if (ndo->ndo_eflag)

sliplink_print(ndo, p, ip, length);

#endif

ip_print(ndo, (u_char *)ip, length);

return (SLIP_HDRLEN);

}

static void

sliplink_print(netdissect_options *ndo,

register const u_char *p, register const struct ip *ip,

register u_int length)

{

int dir;

u_int hlen;

dir = p[SLX_DIR];

ND_PRINT((ndo, dir == SLIPDIR_IN ? "I " : "O "));

if (ndo->ndo_nflag) {

/* XXX just dump the header */

register int i;

for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)

ND_PRINT((ndo, "%02x.", p[i]));

ND_PRINT((ndo, "%02x: ", p[SLX_CHDR + CHDR_LEN - 1]));

return;

}

switch (p[SLX_CHDR] & 0xf0) {

case TYPE_IP:

ND_PRINT((ndo, "ip %d: ", length + SLIP_HDRLEN));

break;

case TYPE_UNCOMPRESSED_TCP:

/*

* The connection id is stored in the IP protocol field.

* Get it from the link layer since sl_uncompress_tcp()

* has restored the IP header copy to IPPROTO_TCP.

*/

lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;

hlen = IP_HL(ip);

hlen += TH_OFF((struct tcphdr *)&((int *)ip)[hlen]);

lastlen[dir][lastconn] = length - (hlen << 2);

ND_PRINT((ndo, "utcp %d: ", lastconn));

break;

default:

if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {

compressed_sl_print(ndo, &p[SLX_CHDR], ip,

length, dir);

ND_PRINT((ndo, ": "));

} else

ND_PRINT((ndo, "slip-%d!: ", p[SLX_CHDR]));

}

}

static const u_char *

print_sl_change(netdissect_options *ndo,

const char *str, register const u_char *cp)

{

register u_int i;

if ((i = *cp++) == 0) {

i = EXTRACT_16BITS(cp);

cp += 2;

}

ND_PRINT((ndo, " %s%d", str, i));

return (cp);

}

static const u_char *

print_sl_winchange(netdissect_options *ndo,

register const u_char *cp)

{

register short i;

if ((i = *cp++) == 0) {

i = EXTRACT_16BITS(cp);

cp += 2;

}

if (i >= 0)

ND_PRINT((ndo, " W+%d", i));

else

ND_PRINT((ndo, " W%d", i));

return (cp);

}

static void

compressed_sl_print(netdissect_options *ndo,

const u_char *chdr, const struct ip *ip,

u_int length, int dir)

{

register const u_char *cp = chdr;

register u_int flags, hlen;

flags = *cp++;

if (flags & NEW_C) {

lastconn = *cp++;

ND_PRINT((ndo, "ctcp %d", lastconn));

} else

ND_PRINT((ndo, "ctcp *"));

/* skip tcp checksum */

cp += 2;

switch (flags & SPECIALS_MASK) {

case SPECIAL_I:

ND_PRINT((ndo, " *SA+%d", lastlen[dir][lastconn]));

break;

case SPECIAL_D:

ND_PRINT((ndo, " *S+%d", lastlen[dir][lastconn]));

break;

default:

if (flags & NEW_U)

cp = print_sl_change(ndo, "U=", cp);

if (flags & NEW_W)

cp = print_sl_winchange(ndo, cp);

if (flags & NEW_A)

cp = print_sl_change(ndo, "A+", cp);

if (flags & NEW_S)

cp = print_sl_change(ndo, "S+", cp);

break;

}

if (flags & NEW_I)

cp = print_sl_change(ndo, "I+", cp);

/*

* 'hlen' is the length of the uncompressed TCP/IP header (in words).

* 'cp - chdr' is the length of the compressed header.

* 'length - hlen' is the amount of data in the packet.

*/

hlen = IP_HL(ip);

hlen += TH_OFF((struct tcphdr *)&((int32_t *)ip)[hlen]);

lastlen[dir][lastconn] = length - (hlen << 2);

ND_PRINT((ndo, " %d (%ld)", lastlen[dir][lastconn], (long)(cp - chdr)));

}