tcpdump/print.c
Guy Harris 6a681e6a16 Have routines that set the snapend take a buffer pointer and length as args.
Have nd_push_buffer() take a snapshot length, not a snapshot end, as
its last argument.

Replace nd_push_snapend() and nd_change_snapend() with nd_push_snaplen()
and nd_change_snaplen(), both of which take a pointer into the packet
buffer and snapshot length relative to that pointer as arguments.  Have
those routines check the snapshot length to make sure it's not bigger
than the number of bytes in the packet past the pointer, and silently
ignore the requst if it is.

Using a length rather than a pointer avoids the possibility of the
calculation of the snapshot end overflowing and resulting in a snapshot
end *before* the point in the buffer.

Add a test for this, with a capture file containing an IPv6 packet with
an extremely large "jumbo" packet size.

Revert the "Make sure we don't set the snapend before the beginning of
the packet." changes, as they no longer apply with this change (which
also makes sure we don't set the snapend before the beginning of the
packet).
2022-03-31 02:29:19 -07:00

577 lines
14 KiB
C

/*
* Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
* 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.
*
* Support for splitting captures into multiple files with a maximum
* file size:
*
* Copyright (c) 2001
* Seth Webster <swebster@sst.ll.mit.edu>
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <setjmp.h>
#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "addrtoname.h"
#include "print.h"
#include "netdissect-alloc.h"
#include "pcap-missing.h"
struct printer {
if_printer f;
int type;
};
static const struct printer printers[] = {
#ifdef DLT_APPLE_IP_OVER_IEEE1394
{ ap1394_if_print, DLT_APPLE_IP_OVER_IEEE1394 },
#endif
{ arcnet_if_print, DLT_ARCNET },
#ifdef DLT_ARCNET_LINUX
{ arcnet_linux_if_print, DLT_ARCNET_LINUX },
#endif
{ atm_if_print, DLT_ATM_RFC1483 },
#ifdef DLT_DSA_TAG_BRCM
{ brcm_tag_if_print, DLT_DSA_TAG_BRCM },
#endif
#ifdef DLT_DSA_TAG_BRCM_PREPEND
{ brcm_tag_prepend_if_print, DLT_DSA_TAG_BRCM_PREPEND },
#endif
#ifdef DLT_BLUETOOTH_HCI_H4_WITH_PHDR
{ bt_if_print, DLT_BLUETOOTH_HCI_H4_WITH_PHDR},
#endif
#ifdef DLT_C_HDLC
{ chdlc_if_print, DLT_C_HDLC },
#endif
#ifdef DLT_HDLC
{ chdlc_if_print, DLT_HDLC },
#endif
#ifdef DLT_ATM_CLIP
{ cip_if_print, DLT_ATM_CLIP },
#endif
#ifdef DLT_CIP
{ cip_if_print, DLT_CIP },
#endif
#ifdef DLT_DSA_TAG_DSA
{ dsa_if_print, DLT_DSA_TAG_DSA },
#endif
#ifdef DLT_DSA_TAG_EDSA
{ edsa_if_print, DLT_DSA_TAG_EDSA },
#endif
#ifdef DLT_ENC
{ enc_if_print, DLT_ENC },
#endif
{ ether_if_print, DLT_EN10MB },
{ fddi_if_print, DLT_FDDI },
#ifdef DLT_FR
{ fr_if_print, DLT_FR },
#endif
#ifdef DLT_FRELAY
{ fr_if_print, DLT_FRELAY },
#endif
#ifdef DLT_IEEE802_11
{ ieee802_11_if_print, DLT_IEEE802_11},
#endif
#ifdef DLT_IEEE802_11_RADIO_AVS
{ ieee802_11_radio_avs_if_print, DLT_IEEE802_11_RADIO_AVS },
#endif
#ifdef DLT_IEEE802_11_RADIO
{ ieee802_11_radio_if_print, DLT_IEEE802_11_RADIO },
#endif
#ifdef DLT_IEEE802_15_4
{ ieee802_15_4_if_print, DLT_IEEE802_15_4 },
#endif
#ifdef DLT_IEEE802_15_4_NOFCS
{ ieee802_15_4_if_print, DLT_IEEE802_15_4_NOFCS },
#endif
#ifdef DLT_IEEE802_15_4_TAP
{ ieee802_15_4_tap_if_print, DLT_IEEE802_15_4_TAP },
#endif
#ifdef DLT_IP_OVER_FC
{ ipfc_if_print, DLT_IP_OVER_FC },
#endif
#ifdef DLT_IPNET
{ ipnet_if_print, DLT_IPNET },
#endif
#ifdef DLT_IPOIB
{ ipoib_if_print, DLT_IPOIB },
#endif
#ifdef DLT_JUNIPER_ATM1
{ juniper_atm1_if_print, DLT_JUNIPER_ATM1 },
#endif
#ifdef DLT_JUNIPER_ATM2
{ juniper_atm2_if_print, DLT_JUNIPER_ATM2 },
#endif
#ifdef DLT_JUNIPER_CHDLC
{ juniper_chdlc_if_print, DLT_JUNIPER_CHDLC },
#endif
#ifdef DLT_JUNIPER_ES
{ juniper_es_if_print, DLT_JUNIPER_ES },
#endif
#ifdef DLT_JUNIPER_ETHER
{ juniper_ether_if_print, DLT_JUNIPER_ETHER },
#endif
#ifdef DLT_JUNIPER_FRELAY
{ juniper_frelay_if_print, DLT_JUNIPER_FRELAY },
#endif
#ifdef DLT_JUNIPER_GGSN
{ juniper_ggsn_if_print, DLT_JUNIPER_GGSN },
#endif
#ifdef DLT_JUNIPER_MFR
{ juniper_mfr_if_print, DLT_JUNIPER_MFR },
#endif
#ifdef DLT_JUNIPER_MLFR
{ juniper_mlfr_if_print, DLT_JUNIPER_MLFR },
#endif
#ifdef DLT_JUNIPER_MLPPP
{ juniper_mlppp_if_print, DLT_JUNIPER_MLPPP },
#endif
#ifdef DLT_JUNIPER_MONITOR
{ juniper_monitor_if_print, DLT_JUNIPER_MONITOR },
#endif
#ifdef DLT_JUNIPER_PPP
{ juniper_ppp_if_print, DLT_JUNIPER_PPP },
#endif
#ifdef DLT_JUNIPER_PPPOE_ATM
{ juniper_pppoe_atm_if_print, DLT_JUNIPER_PPPOE_ATM },
#endif
#ifdef DLT_JUNIPER_PPPOE
{ juniper_pppoe_if_print, DLT_JUNIPER_PPPOE },
#endif
#ifdef DLT_JUNIPER_SERVICES
{ juniper_services_if_print, DLT_JUNIPER_SERVICES },
#endif
#ifdef DLT_LTALK
{ ltalk_if_print, DLT_LTALK },
#endif
#ifdef DLT_MFR
{ mfr_if_print, DLT_MFR },
#endif
#ifdef DLT_NETANALYZER
{ netanalyzer_if_print, DLT_NETANALYZER },
#endif
#ifdef DLT_NETANALYZER_TRANSPARENT
{ netanalyzer_transparent_if_print, DLT_NETANALYZER_TRANSPARENT },
#endif
#ifdef DLT_NFLOG
{ nflog_if_print, DLT_NFLOG},
#endif
{ null_if_print, DLT_NULL },
#ifdef DLT_LOOP
{ null_if_print, DLT_LOOP },
#endif
#ifdef DLT_PFLOG
{ pflog_if_print, DLT_PFLOG },
#endif
#ifdef DLT_PKTAP
{ pktap_if_print, DLT_PKTAP },
#endif
#ifdef DLT_PPI
{ ppi_if_print, DLT_PPI },
#endif
#ifdef DLT_PPP_BSDOS
{ ppp_bsdos_if_print, DLT_PPP_BSDOS },
#endif
#ifdef DLT_PPP_SERIAL
{ ppp_hdlc_if_print, DLT_PPP_SERIAL },
#endif
{ ppp_if_print, DLT_PPP },
#ifdef DLT_PPP_PPPD
{ ppp_if_print, DLT_PPP_PPPD },
#endif
#ifdef DLT_PPP_ETHER
{ pppoe_if_print, DLT_PPP_ETHER },
#endif
#ifdef DLT_PRISM_HEADER
{ prism_if_print, DLT_PRISM_HEADER },
#endif
{ raw_if_print, DLT_RAW },
#ifdef DLT_IPV4
{ raw_if_print, DLT_IPV4 },
#endif
#ifdef DLT_IPV6
{ raw_if_print, DLT_IPV6 },
#endif
#ifdef DLT_SLIP_BSDOS
{ sl_bsdos_if_print, DLT_SLIP_BSDOS },
#endif
{ sl_if_print, DLT_SLIP },
#ifdef DLT_LINUX_SLL
{ sll_if_print, DLT_LINUX_SLL },
#endif
#ifdef DLT_LINUX_SLL2
{ sll2_if_print, DLT_LINUX_SLL2 },
#endif
#ifdef DLT_SUNATM
{ sunatm_if_print, DLT_SUNATM },
#endif
#ifdef DLT_SYMANTEC_FIREWALL
{ symantec_if_print, DLT_SYMANTEC_FIREWALL },
#endif
{ token_if_print, DLT_IEEE802 },
#ifdef DLT_USB_LINUX
{ usb_linux_48_byte_if_print, DLT_USB_LINUX},
#endif /* DLT_USB_LINUX */
#ifdef DLT_USB_LINUX_MMAPPED
{ usb_linux_64_byte_if_print, DLT_USB_LINUX_MMAPPED},
#endif /* DLT_USB_LINUX_MMAPPED */
#ifdef DLT_VSOCK
{ vsock_if_print, DLT_VSOCK },
#endif
{ NULL, 0 },
};
void
init_print(netdissect_options *ndo, uint32_t localnet, uint32_t mask)
{
init_addrtoname(ndo, localnet, mask);
init_checksum();
}
if_printer
lookup_printer(int type)
{
const struct printer *p;
for (p = printers; p->f; ++p)
if (type == p->type)
return p->f;
#if defined(DLT_USER2) && defined(DLT_PKTAP)
/*
* Apple incorrectly chose to use DLT_USER2 for their PKTAP
* header.
*
* We map DLT_PKTAP, whether it's DLT_USER2 as it is on Darwin-
* based OSes or the same value as LINKTYPE_PKTAP as it is on
* other OSes, to LINKTYPE_PKTAP, so files written with
* this version of libpcap for a DLT_PKTAP capture have a link-
* layer header type of LINKTYPE_PKTAP.
*
* However, files written on OS X Mavericks for a DLT_PKTAP
* capture have a link-layer header type of LINKTYPE_USER2.
* If we don't have a printer for DLT_USER2, and type is
* DLT_USER2, we look up the printer for DLT_PKTAP and use
* that.
*/
if (type == DLT_USER2) {
for (p = printers; p->f; ++p)
if (DLT_PKTAP == p->type)
return p->f;
}
#endif
return NULL;
/* NOTREACHED */
}
int
has_printer(int type)
{
return (lookup_printer(type) != NULL);
}
if_printer
get_if_printer(int type)
{
if_printer printer;
printer = lookup_printer(type);
if (printer == NULL)
printer = unsupported_if_print;
return printer;
}
#ifdef ENABLE_INSTRUMENT_FUNCTIONS
extern int profile_func_level;
static int pretty_print_packet_level = -1;
#endif
void
pretty_print_packet(netdissect_options *ndo, const struct pcap_pkthdr *h,
const u_char *sp, u_int packets_captured)
{
u_int hdrlen = 0;
int invalid_header = 0;
if (ndo->ndo_print_sampling && packets_captured % ndo->ndo_print_sampling != 0)
return;
#ifdef ENABLE_INSTRUMENT_FUNCTIONS
if (pretty_print_packet_level == -1)
pretty_print_packet_level = profile_func_level;
#endif
if (ndo->ndo_packet_number)
ND_PRINT("%5u ", packets_captured);
/* Sanity checks on packet length / capture length */
if (h->caplen == 0) {
invalid_header = 1;
ND_PRINT("[Invalid header: caplen==0");
}
if (h->len == 0) {
if (!invalid_header) {
invalid_header = 1;
ND_PRINT("[Invalid header:");
} else
ND_PRINT(",");
ND_PRINT(" len==0");
} else if (h->len < h->caplen) {
if (!invalid_header) {
invalid_header = 1;
ND_PRINT("[Invalid header:");
} else
ND_PRINT(",");
ND_PRINT(" len(%u) < caplen(%u)", h->len, h->caplen);
}
if (h->caplen > MAXIMUM_SNAPLEN) {
if (!invalid_header) {
invalid_header = 1;
ND_PRINT("[Invalid header:");
} else
ND_PRINT(",");
ND_PRINT(" caplen(%u) > %u", h->caplen, MAXIMUM_SNAPLEN);
}
if (h->len > MAXIMUM_SNAPLEN) {
if (!invalid_header) {
invalid_header = 1;
ND_PRINT("[Invalid header:");
} else
ND_PRINT(",");
ND_PRINT(" len(%u) > %u", h->len, MAXIMUM_SNAPLEN);
}
if (invalid_header) {
ND_PRINT("]\n");
return;
}
/*
* At this point:
* capture length != 0,
* packet length != 0,
* capture length <= MAXIMUM_SNAPLEN,
* packet length <= MAXIMUM_SNAPLEN,
* packet length >= capture length.
*
* Currently, there is no D-Bus printer, thus no need for
* bigger lengths.
*/
/*
* The header /usr/include/pcap/pcap.h in OpenBSD declares h->ts as
* struct bpf_timeval, not struct timeval. The former comes from
* /usr/include/net/bpf.h and uses 32-bit unsigned types instead of
* the types used in struct timeval.
*/
struct timeval tvbuf;
tvbuf.tv_sec = h->ts.tv_sec;
tvbuf.tv_usec = h->ts.tv_usec;
ts_print(ndo, &tvbuf);
/*
* Printers must check that they're not walking off the end of
* the packet.
* Rather than pass it all the way down, we set this member
* of the netdissect_options structure.
*/
ndo->ndo_snapend = sp + h->caplen;
ndo->ndo_packetp = sp;
ndo->ndo_protocol = "";
ndo->ndo_ll_hdr_len = 0;
switch (setjmp(ndo->ndo_early_end)) {
case 0:
/* Print the packet. */
(ndo->ndo_if_printer)(ndo, h, sp);
break;
case ND_TRUNCATED:
/* A printer quit because the packet was truncated; report it */
nd_print_trunc(ndo);
/* Print the full packet */
ndo->ndo_ll_hdr_len = 0;
#ifdef ENABLE_INSTRUMENT_FUNCTIONS
/* truncation => reassignment */
profile_func_level = pretty_print_packet_level;
#endif
break;
}
hdrlen = ndo->ndo_ll_hdr_len;
/*
* Empty the stack of packet information, freeing all pushed buffers;
* if we got here by a printer quitting, we need to release anything
* that didn't get released because we longjmped out of the code
* before it popped the packet information.
*/
nd_pop_all_packet_info(ndo);
/*
* Restore the original snapend, as a printer might have
* changed it.
*/
ndo->ndo_snapend = sp + h->caplen;
if (ndo->ndo_Xflag) {
/*
* Print the raw packet data in hex and ASCII.
*/
if (ndo->ndo_Xflag > 1) {
/*
* Include the link-layer header.
*/
hex_and_ascii_print(ndo, "\n\t", sp, h->caplen);
} else {
/*
* Don't include the link-layer header - and if
* we have nothing past the link-layer header,
* print nothing.
*/
if (h->caplen > hdrlen)
hex_and_ascii_print(ndo, "\n\t", sp + hdrlen,
h->caplen - hdrlen);
}
} else if (ndo->ndo_xflag) {
/*
* Print the raw packet data in hex.
*/
if (ndo->ndo_xflag > 1) {
/*
* Include the link-layer header.
*/
hex_print(ndo, "\n\t", sp, h->caplen);
} else {
/*
* Don't include the link-layer header - and if
* we have nothing past the link-layer header,
* print nothing.
*/
if (h->caplen > hdrlen)
hex_print(ndo, "\n\t", sp + hdrlen,
h->caplen - hdrlen);
}
} else if (ndo->ndo_Aflag) {
/*
* Print the raw packet data in ASCII.
*/
if (ndo->ndo_Aflag > 1) {
/*
* Include the link-layer header.
*/
ascii_print(ndo, sp, h->caplen);
} else {
/*
* Don't include the link-layer header - and if
* we have nothing past the link-layer header,
* print nothing.
*/
if (h->caplen > hdrlen)
ascii_print(ndo, sp + hdrlen, h->caplen - hdrlen);
}
}
ND_PRINT("\n");
nd_free_all(ndo);
}
/*
* By default, print the specified data out in hex and ASCII.
*/
static void
ndo_default_print(netdissect_options *ndo, const u_char *bp, u_int length)
{
hex_and_ascii_print(ndo, "\n\t", bp, length); /* pass on lf and indentation string */
}
/* VARARGS */
static void NORETURN PRINTFLIKE(3, 4)
ndo_error(netdissect_options *ndo, status_exit_codes_t status,
FORMAT_STRING(const char *fmt), ...)
{
va_list ap;
if (ndo->program_name)
(void)fprintf(stderr, "%s: ", ndo->program_name);
va_start(ap, fmt);
(void)vfprintf(stderr, fmt, ap);
va_end(ap);
if (*fmt) {
fmt += strlen(fmt);
if (fmt[-1] != '\n')
(void)fputc('\n', stderr);
}
nd_cleanup();
exit(status);
/* NOTREACHED */
}
/* VARARGS */
static void PRINTFLIKE(2, 3)
ndo_warning(netdissect_options *ndo, FORMAT_STRING(const char *fmt), ...)
{
va_list ap;
if (ndo->program_name)
(void)fprintf(stderr, "%s: ", ndo->program_name);
(void)fprintf(stderr, "WARNING: ");
va_start(ap, fmt);
(void)vfprintf(stderr, fmt, ap);
va_end(ap);
if (*fmt) {
fmt += strlen(fmt);
if (fmt[-1] != '\n')
(void)fputc('\n', stderr);
}
}
/* VARARGS */
static int PRINTFLIKE(2, 3)
ndo_printf(netdissect_options *ndo, FORMAT_STRING(const char *fmt), ...)
{
va_list args;
int ret;
va_start(args, fmt);
ret = vfprintf(stdout, fmt, args);
va_end(args);
if (ret < 0)
ndo_error(ndo, S_ERR_ND_WRITE_FILE,
"Unable to write output: %s", pcap_strerror(errno));
return (ret);
}
void
ndo_set_function_pointers(netdissect_options *ndo)
{
ndo->ndo_default_print=ndo_default_print;
ndo->ndo_printf=ndo_printf;
ndo->ndo_error=ndo_error;
ndo->ndo_warning=ndo_warning;
}