tcpdump/print-sl.c
Francois-Xavier Le Bail 5cea270318 Remove all storage class specifier 'register'
Let the compiler do the optimizations (or not) based on build options.

Avoid 'value has been optimized out' messages in gdb using '-O0'.
2017-12-13 19:17:47 +01:00

281 lines
6.7 KiB
C

/*
* 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.
*/
/* \summary: Compressed Serial Line Internet Protocol printer */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <netdissect-stdinc.h>
#include "netdissect.h"
#include "extract.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)
{
u_int caplen = h->caplen;
u_int length = h->len;
const struct ip *ip;
if (caplen < SLIP_HDRLEN || length < SLIP_HDRLEN) {
ND_PRINT((ndo, "%s", tstr));
return (caplen);
}
caplen -= SLIP_HDRLEN;
length -= SLIP_HDRLEN;
ip = (const struct ip *)(p + SLIP_HDRLEN);
if (ndo->ndo_eflag)
sliplink_print(ndo, p, ip, length);
if (caplen < 1 || length < 1) {
ND_PRINT((ndo, "%s", tstr));
return (caplen + SLIP_HDRLEN);
}
switch (IP_V(ip)) {
case 4:
ip_print(ndo, (const u_char *)ip, length);
break;
case 6:
ip6_print(ndo, (const 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)
{
u_int caplen = h->caplen;
u_int length = h->len;
const struct ip *ip;
if (caplen < SLIP_HDRLEN) {
ND_PRINT((ndo, "%s", tstr));
return (caplen);
}
length -= SLIP_HDRLEN;
ip = (const struct ip *)(p + SLIP_HDRLEN);
#ifdef notdef
if (ndo->ndo_eflag)
sliplink_print(ndo, p, ip, length);
#endif
ip_print(ndo, (const u_char *)ip, length);
return (SLIP_HDRLEN);
}
static void
sliplink_print(netdissect_options *ndo,
const u_char *p, const struct ip *ip,
u_int length)
{
int dir;
u_int hlen;
dir = EXTRACT_U_1(p + SLX_DIR);
switch (dir) {
case SLIPDIR_IN:
ND_PRINT((ndo, "I "));
break;
case SLIPDIR_OUT:
ND_PRINT((ndo, "O "));
break;
default:
ND_PRINT((ndo, "Invalid direction %d ", dir));
dir = -1;
break;
}
if (ndo->ndo_nflag) {
/* XXX just dump the header */
int i;
for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
ND_PRINT((ndo, "%02x.", EXTRACT_U_1(p + i)));
ND_PRINT((ndo, "%02x: ", EXTRACT_U_1(p + SLX_CHDR + CHDR_LEN - 1)));
return;
}
switch (EXTRACT_U_1(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 = EXTRACT_U_1(((const struct ip *)(p + SLX_CHDR))->ip_p);
ND_PRINT((ndo, "utcp %d: ", lastconn));
if (dir == -1) {
/* Direction is bogus, don't use it */
return;
}
hlen = IP_HL(ip);
hlen += TH_OFF((const struct tcphdr *)&((const int *)ip)[hlen]);
lastlen[dir][lastconn] = length - (hlen << 2);
break;
default:
if (dir == -1) {
/* Direction is bogus, don't use it */
return;
}
if (EXTRACT_U_1(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!: ", EXTRACT_U_1(p + SLX_CHDR)));
}
}
static const u_char *
print_sl_change(netdissect_options *ndo,
const char *str, const u_char *cp)
{
u_int i;
if ((i = EXTRACT_U_1(cp)) == 0) {
cp++;
i = EXTRACT_BE_U_2(cp);
cp += 2;
}
ND_PRINT((ndo, " %s%d", str, i));
return (cp);
}
static const u_char *
print_sl_winchange(netdissect_options *ndo,
const u_char *cp)
{
short i;
if ((i = EXTRACT_U_1(cp)) == 0) {
cp++;
i = EXTRACT_BE_U_2(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)
{
const u_char *cp = chdr;
u_int flags, hlen;
flags = EXTRACT_U_1(cp);
cp++;
if (flags & NEW_C) {
lastconn = EXTRACT_U_1(cp);
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((const struct tcphdr *)&((const int32_t *)ip)[hlen]);
lastlen[dir][lastconn] = length - (hlen << 2);
ND_PRINT((ndo, " %d (%ld)", lastlen[dir][lastconn], (long)(cp - chdr)));
}