/*
* Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
* 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 the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the Computer Systems
* Engineering Group at Lawrence Berkeley Laboratory.
* 4. Neither the name of the University nor of the Laboratory may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char rcsid[] _U_ =
"@(#) $Header: /tcpdump/master/libpcap/pcap.c,v 1.128 2008-12-23 20:13:29 guy Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef WIN32
#include <pcap-stdinc.h>
#else /* WIN32 */
#if HAVE_INTTYPES_H
#include <inttypes.h>
#elif HAVE_STDINT_H
#include <stdint.h>
#endif
#ifdef HAVE_SYS_BITYPES_H
#include <sys/bitypes.h>
#endif
#include <sys/types.h>
#endif /* WIN32 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if !defined(_MSC_VER) && !defined(__BORLANDC__) && !defined(__MINGW32__)
#include <unistd.h>
#endif
#include <fcntl.h>
#include <errno.h>
#ifdef HAVE_OS_PROTO_H
#include "os-proto.h"
#endif
#ifdef MSDOS
#include "pcap-dos.h"
#endif
#include "pcap-int.h"
#ifdef HAVE_DAG_API
#include "pcap-dag.h"
#endif /* HAVE_DAG_API */
#ifdef HAVE_SEPTEL_API
#include "pcap-septel.h"
#endif /* HAVE_SEPTEL_API */
#ifdef HAVE_SNF_API
#include "pcap-snf.h"
#endif /* HAVE_SNF_API */
#ifdef PCAP_SUPPORT_USB
#include "pcap-usb-linux.h"
#endif
#ifdef PCAP_SUPPORT_BT
#include "pcap-bt-linux.h"
#endif
#ifdef PCAP_SUPPORT_CAN
#include "pcap-can-linux.h"
#endif
#ifdef PCAP_SUPPORT_CANUSB
#include "pcap-canusb-linux.h"
#endif
#ifdef PCAP_SUPPORT_NETFILTER
#include "pcap-netfilter-linux.h"
#endif
#ifdef PCAP_SUPPORT_DBUS
#include "pcap-dbus.h"
#endif
int
pcap_not_initialized(pcap_t *pcap _U_)
{
/* this means 'not initialized' */
return (PCAP_ERROR_NOT_ACTIVATED);
}
#ifdef WIN32
Adapter *
pcap_no_adapter(pcap_t *pcap _U_)
{
return (NULL);
}
#endif
/*
* Returns 1 if rfmon mode can be set on the pcap_t, 0 if it can't,
* a PCAP_ERROR value on an error.
*/
int
pcap_can_set_rfmon(pcap_t *p)
{
return (p->can_set_rfmon_op(p));
}
/*
* For systems where rfmon mode is never supported.
*/
static int
pcap_cant_set_rfmon(pcap_t *p _U_)
{
return (0);
}
/*
* Sets *tstamp_typesp to point to an array 1 or more supported time stamp
* types; the return value is the number of supported time stamp types.
* The list should be freed by a call to pcap_free_tstamp_types() when
* you're done with it.
*
* A return value of 0 means "you don't get a choice of time stamp type",
* in which case *tstamp_typesp is set to null.
*
* PCAP_ERROR is returned on error.
*/
int
pcap_list_tstamp_types(pcap_t *p, int **tstamp_typesp)
{
if (p->tstamp_type_count == 0) {
/*
* We don't support multiple time stamp types.
*/
*tstamp_typesp = NULL;
} else {
*tstamp_typesp = (int*)calloc(sizeof(**tstamp_typesp),
p->tstamp_type_count);
if (*tstamp_typesp == NULL) {
(void)snprintf(p->errbuf, sizeof(p->errbuf),
"malloc: %s", pcap_strerror(errno));
return (PCAP_ERROR);
}
(void)memcpy(*tstamp_typesp, p->tstamp_type_list,
sizeof(**tstamp_typesp) * p->tstamp_type_count);
}
return (p->tstamp_type_count);
}
/*
* In Windows, you might have a library built with one version of the
* C runtime library and an application built with another version of
* the C runtime library, which means that the library might use one
* version of malloc() and free() and the application might use another
* version of malloc() and free(). If so, that means something
* allocated by the library cannot be freed by the application, so we
* need to have a pcap_free_tstamp_types() routine to free up the list
* allocated by pcap_list_tstamp_types(), even though it's just a wrapper
* around free().
*/
void
pcap_free_tstamp_types(int *tstamp_type_list)
{
free(tstamp_type_list);
}
/*
* Default one-shot callback; overridden for capture types where the
* packet data cannot be guaranteed to be available after the callback
* returns, so that a copy must be made.
*/
void
pcap_oneshot(u_char *user, const struct pcap_pkthdr *h, const u_char *pkt)
{
struct oneshot_userdata *sp = (struct oneshot_userdata *)user;
*sp->hdr = *h;
*sp->pkt = pkt;
}
const u_char *
pcap_next(pcap_t *p, struct pcap_pkthdr *h)
{
struct oneshot_userdata s;
const u_char *pkt;
s.hdr = h;
s.pkt = &pkt;
s.pd = p;
if (pcap_dispatch(p, 1, p->oneshot_callback, (u_char *)&s) <= 0)
return (0);
return (pkt);
}
int
pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header,
const u_char **pkt_data)
{
struct oneshot_userdata s;
s.hdr = &p->pcap_header;
s.pkt = pkt_data;
s.pd = p;
/* Saves a pointer to the packet headers */
*pkt_header= &p->pcap_header;
if (p->rfile != NULL) {
int status;
/* We are on an offline capture */
status = pcap_offline_read(p, 1, p->oneshot_callback,
(u_char *)&s);
/*
* Return codes for pcap_offline_read() are:
* - 0: EOF
* - -1: error
* - >1: OK
* The first one ('0') conflicts with the return code of
* 0 from pcap_read() meaning "no packets arrived before
* the timeout expired", so we map it to -2 so you can
* distinguish between an EOF from a savefile and a
* "no packets arrived before the timeout expired, try
* again" from a live capture.
*/
if (status == 0)
return (-2);
else
return (status);
}
/*
* Return codes for pcap_read() are:
* - 0: timeout
* - -1: error
* - -2: loop was broken out of with pcap_breakloop()
* - >1: OK
* The first one ('0') conflicts with the return code of 0 from
* pcap_offline_read() meaning "end of file".
*/
return (p->read_op(p, 1, p->oneshot_callback, (u_char *)&s));
}
#if defined(DAG_ONLY)
int
pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
{
return (dag_findalldevs(alldevsp, errbuf));
}
pcap_t *
pcap_create(const char *source, char *errbuf)
{
return (dag_create(source, errbuf));
}
#elif defined(SEPTEL_ONLY)
int
pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
{
return (septel_findalldevs(alldevsp, errbuf));
}
pcap_t *
pcap_create(const char *source, char *errbuf)
{
return (septel_create(source, errbuf));
}
#elif defined(SNF_ONLY)
int
pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
{
return (snf_findalldevs(alldevsp, errbuf));
}
pcap_t *
pcap_create(const char *source, char *errbuf)
{
return (snf_create(source, errbuf));
}
#else /* regular pcap */
struct capture_source_type {
int (*findalldevs_op)(pcap_if_t **, char *);
pcap_t *(*create_op)(const char *, char *, int *);
} capture_source_types[] = {
#ifdef HAVE_DAG_API
{ dag_findalldevs, dag_create },
#endif
#ifdef HAVE_SEPTEL_API
{ septel_findalldevs, septel_create },
#endif
#ifdef HAVE_SNF_API
{ snf_findalldevs, snf_create },
#endif
#ifdef PCAP_SUPPORT_BT
{ bt_findalldevs, bt_create },
#endif
#if PCAP_SUPPORT_CANUSB
{ canusb_findalldevs, canusb_create },
#endif
#ifdef PCAP_SUPPORT_CAN
{ can_findalldevs, can_create },
#endif
#ifdef PCAP_SUPPORT_USB
{ usb_findalldevs, usb_create },
#endif
#ifdef PCAP_SUPPORT_NETFILTER
{ netfilter_findalldevs, netfilter_create },
#endif
#ifdef PCAP_SUPPORT_DBUS
{ dbus_findalldevs, dbus_create },
#endif
{ NULL, NULL }
};
/*
* Get a list of all capture sources that are up and that we can open.
* Returns -1 on error, 0 otherwise.
* The list, as returned through "alldevsp", may be null if no interfaces
* were up and could be opened.
*/
int
pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
{
size_t i;
/*
* Get the list of regular interfaces first.
*/
if (pcap_findalldevs_interfaces(alldevsp, errbuf) == -1)
return (-1); /* failure */
/*
* Add any interfaces that need a platform-specific mechanism
* to find.
*/
if (pcap_platform_finddevs(alldevsp, errbuf) == -1) {
/*
* We had an error; free the list we've been
* constructing.
*/
if (*alldevsp != NULL) {
pcap_freealldevs(*alldevsp);
*alldevsp = NULL;
}
return (-1);
}
/*
* Ask each of the non-local-network-interface capture
* source types what interfaces they have.
*/
for (i = 0; capture_source_types[i].findalldevs_op != NULL; i++) {
if (capture_source_types[i].findalldevs_op(alldevsp, errbuf) == -1) {
/*
* We had an error; free the list we've been
* constructing.
*/
if (*alldevsp != NULL) {
pcap_freealldevs(*alldevsp);
*alldevsp = NULL;
}
return (-1);
}
}
return (0);
}
pcap_t *
pcap_create(const char *source, char *errbuf)
{
size_t i;
int is_theirs;
pcap_t *p;
/*
* A null source name is equivalent to the "any" device -
* which might not be supported on this platform, but
* this means that you'll get a "not supported" error
* rather than, say, a crash when we try to dereference
* the null pointer.
*/
if (source == NULL)
source = "any";
/*
* Try each of the non-local-network-interface capture
* source types until we find one that works for this
* device or run out of types.
*/
for (i = 0; capture_source_types[i].create_op != NULL; i++) {
is_theirs = 0;
p = capture_source_types[i].create_op(source, errbuf, &is_theirs);
if (is_theirs) {
/*
* The device name refers to a device of the
* type in question; either it succeeded,
* in which case p refers to a pcap_t to
* later activate for the device, or it
* failed, in which case p is null and we
* should return that to report the failure
* to create.
*/
return (p);
}
}
/*
* OK, try it as a regular network interface.
*/
return (pcap_create_interface(source, errbuf));
}
#endif
static void
initialize_ops(pcap_t *p)
{
/*
* Set operation pointers for operations that only work on
* an activated pcap_t to point to a routine that returns
* a "this isn't activated" error.
*/
p->read_op = (read_op_t)pcap_not_initialized;
p->inject_op = (inject_op_t)pcap_not_initialized;
p->setfilter_op = (setfilter_op_t)pcap_not_initialized;
p->setdirection_op = (setdirection_op_t)pcap_not_initialized;
p->set_datalink_op = (set_datalink_op_t)pcap_not_initialized;
p->getnonblock_op = (getnonblock_op_t)pcap_not_initialized;
p->setnonblock_op = (setnonblock_op_t)pcap_not_initialized;
p->stats_op = (stats_op_t)pcap_not_initialized;
#ifdef WIN32
p->setbuff_op = (setbuff_op_t)pcap_not_initialized;
p->setmode_op = (setmode_op_t)pcap_not_initialized;
p->setmintocopy_op = (setmintocopy_op_t)pcap_not_initialized;
p->getadapter_op = pcap_no_adapter;
#endif
/*
* Default cleanup operation - implementations can override
* this, but should call pcap_cleanup_live_common() after
* doing their own additional cleanup.
*/
p->cleanup_op = pcap_cleanup_live_common;
/*
* In most cases, the standard one-shot callback can
* be used for pcap_next()/pcap_next_ex().
*/
p->oneshot_callback = pcap_oneshot;
}
static pcap_t *
pcap_alloc_pcap_t(char *ebuf, size_t size)
{
char *chunk;
pcap_t *p;
/*
* Allocate a chunk of memory big enough for a pcap_t
* plus a structure following it of size "size". The
* structure following it is a private data structure
* for the routines that handle this pcap_t.
*/
chunk = malloc(sizeof (pcap_t) + size);
if (chunk == NULL) {
snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
pcap_strerror(errno));
return (NULL);
}
memset(chunk, 0, sizeof (pcap_t) + size);
/*
* Get a pointer to the pcap_t at the beginning.
*/
p = (pcap_t *)chunk;
#ifndef WIN32
p->fd = -1; /* not opened yet */
p->selectable_fd = -1;
#endif
if (size == 0) {
/* No private data was requested. */
p->priv = NULL;
} else {
/*
* Set the pointer to the private data; that's the structure
* of size "size" following the pcap_t.
*/
p->priv = (void *)(chunk + sizeof (pcap_t));
}
return (p);
}
pcap_t *
pcap_create_common(const char *source, char *ebuf, size_t size)
{
pcap_t *p;
p = pcap_alloc_pcap_t(ebuf, size);
if (p == NULL)
return (NULL);
p->opt.source = strdup(source);
if (p->opt.source == NULL) {
snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
pcap_strerror(errno));
free(p);
return (NULL);
}
/*
* Default to "can't set rfmon mode"; if it's supported by
* a platform, the create routine that called us can set
* the op to its routine to check whether a particular
* device supports it.
*/
p->can_set_rfmon_op = pcap_cant_set_rfmon;
initialize_ops(p);
/* put in some defaults*/
pcap_set_snaplen(p, 65535); /* max packet size */
p->opt.timeout = 0; /* no timeout specified */
p->opt.buffer_size = 0; /* use the platform's default */
p->opt.promisc = 0;
p->opt.rfmon = 0;
p->opt.immediate = 0;
p->opt.tstamp_type = -1; /* default to not setting time stamp type */
p->opt.tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
return (p);
}
int
pcap_check_activated(pcap_t *p)
{
if (p->activated) {
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "can't perform "
" operation on activated capture");
return (-1);
}
return (0);
}
int
pcap_set_snaplen(pcap_t *p, int snaplen)
{
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
p->snapshot = snaplen;
return (0);
}
int
pcap_set_promisc(pcap_t *p, int promisc)
{
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
p->opt.promisc = promisc;
return (0);
}
int
pcap_set_rfmon(pcap_t *p, int rfmon)
{
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
p->opt.rfmon = rfmon;
return (0);
}
int
pcap_set_timeout(pcap_t *p, int timeout_ms)
{
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
p->opt.timeout = timeout_ms;
return (0);
}
int
pcap_set_tstamp_type(pcap_t *p, int tstamp_type)
{
int i;
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
/*
* If p->tstamp_type_count is 0, we only support PCAP_TSTAMP_HOST;
* the default time stamp type is PCAP_TSTAMP_HOST.
*/
if (p->tstamp_type_count == 0) {
if (tstamp_type == PCAP_TSTAMP_HOST) {
p->opt.tstamp_type = tstamp_type;
return (0);
}
} else {
/*
* Check whether we claim to support this type of time stamp.
*/
for (i = 0; i < p->tstamp_type_count; i++) {
if (p->tstamp_type_list[i] == tstamp_type) {
/*
* Yes.
*/
p->opt.tstamp_type = tstamp_type;
return (0);
}
}
}
/*
* We don't support this type of time stamp.
*/
return (PCAP_WARNING_TSTAMP_TYPE_NOTSUP);
}
int
pcap_set_immediate_mode(pcap_t *p, int immediate)
{
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
p->opt.immediate = immediate;
return (0);
}
int
pcap_set_buffer_size(pcap_t *p, int buffer_size)
{
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
p->opt.buffer_size = buffer_size;
return (0);
}
int
pcap_set_tstamp_precision(pcap_t *p, int tstamp_precision)
{
int i;
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
/*
* If p->tstamp_precision_count is 0, we only support setting
* the time stamp precision to microsecond precision; every
* pcap module *MUST* support microsecond precision, even if
* it does so by converting the native precision to
* microseconds.
*/
if (p->tstamp_precision_count == 0) {
if (tstamp_precision == PCAP_TSTAMP_PRECISION_MICRO) {
p->opt.tstamp_precision = tstamp_precision;
return (0);
}
} else {
/*
* Check whether we claim to support this precision of
* time stamp.
*/
for (i = 0; i < p->tstamp_precision_count; i++) {
if (p->tstamp_precision_list[i] == tstamp_precision) {
/*
* Yes.
*/
p->opt.tstamp_precision = tstamp_precision;
return (0);
}
}
}
/*
* We don't support this time stamp precision.
*/
return (PCAP_ERROR_TSTAMP_PRECISION_NOTSUP);
}
int
pcap_get_tstamp_precision(pcap_t *p)
{
return (p->opt.tstamp_precision);
}
int
pcap_activate(pcap_t *p)
{
int status;
/*
* Catch attempts to re-activate an already-activated
* pcap_t; this should, for example, catch code that
* calls pcap_open_live() followed by pcap_activate(),
* as some code that showed up in a Stack Exchange
* question did.
*/
if (pcap_check_activated(p))
return (PCAP_ERROR_ACTIVATED);
status = p->activate_op(p);
if (status >= 0)
p->activated = 1;
else {
if (p->errbuf[0] == '\0') {
/*
* No error message supplied by the activate routine;
* for the benefit of programs that don't specially
* handle errors other than PCAP_ERROR, return the
* error message corresponding to the status.
*/
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s",
pcap_statustostr(status));
}
/*
* Undo any operation pointer setting, etc. done by
* the activate operation.
*/
initialize_ops(p);
}
return (status);
}
pcap_t *
pcap_open_live(const char *source, int snaplen, int promisc, int to_ms, char *errbuf)
{
pcap_t *p;
int status;
p = pcap_create(source, errbuf);
if (p == NULL)
return (NULL);
status = pcap_set_snaplen(p, snaplen);
if (status < 0)
goto fail;
status = pcap_set_promisc(p, promisc);
if (status < 0)
goto fail;
status = pcap_set_timeout(p, to_ms);
if (status < 0)
goto fail;
/*
* Mark this as opened with pcap_open_live(), so that, for
* example, we show the full list of DLT_ values, rather
* than just the ones that are compatible with capturing
* when not in monitor mode. That allows existing applications
* to work the way they used to work, but allows new applications
* that know about the new open API to, for example, find out the
* DLT_ values that they can select without changing whether
* the adapter is in monitor mode or not.
*/
p->oldstyle = 1;
status = pcap_activate(p);
if (status < 0)
goto fail;
return (p);
fail:
if (status == PCAP_ERROR)
snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", source,
p->errbuf);
else if (status == PCAP_ERROR_NO_SUCH_DEVICE ||
status == PCAP_ERROR_PERM_DENIED ||
status == PCAP_ERROR_PROMISC_PERM_DENIED)
snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s (%s)", source,
pcap_statustostr(status), p->errbuf);
else
snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", source,
pcap_statustostr(status));
pcap_close(p);
return (NULL);
}
pcap_t *
pcap_open_offline_common(char *ebuf, size_t size)
{
pcap_t *p;
p = pcap_alloc_pcap_t(ebuf, size);
if (p == NULL)
return (NULL);
p->opt.tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
p->opt.source = strdup("(savefile)");
if (p->opt.source == NULL) {
snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
pcap_strerror(errno));
free(p);
return (NULL);
}
return (p);
}
int
pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
return (p->read_op(p, cnt, callback, user));
}
/*
* XXX - is this necessary?
*/
int
pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
return (p->read_op(p, cnt, callback, user));
}
int
pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
register int n;
for (;;) {
if (p->rfile != NULL) {
/*
* 0 means EOF, so don't loop if we get 0.
*/
n = pcap_offline_read(p, cnt, callback, user);
} else {
/*
* XXX keep reading until we get something
* (or an error occurs)
*/
do {
n = p->read_op(p, cnt, callback, user);
} while (n == 0);
}
if (n <= 0)
return (n);
if (!PACKET_COUNT_IS_UNLIMITED(cnt)) {
cnt -= n;
if (cnt <= 0)
return (0);
}
}
}
/*
* Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate.
*/
void
pcap_breakloop(pcap_t *p)
{
p->break_loop = 1;
}
int
pcap_datalink(pcap_t *p)
{
if (!p->activated)
return (PCAP_ERROR_NOT_ACTIVATED);
return (p->linktype);
}
int
pcap_datalink_ext(pcap_t *p)
{
if (!p->activated)
return (PCAP_ERROR_NOT_ACTIVATED);
return (p->linktype_ext);
}
int
pcap_list_datalinks(pcap_t *p, int **dlt_buffer)
{
if (!p->activated)
return (PCAP_ERROR_NOT_ACTIVATED);
if (p->dlt_count == 0) {
/*
* We couldn't fetch the list of DLTs, which means
* this platform doesn't support changing the
* DLT for an interface. Return a list of DLTs
* containing only the DLT this device supports.
*/
*dlt_buffer = (int*)malloc(sizeof(**dlt_buffer));
if (*dlt_buffer == NULL) {
(void)snprintf(p->errbuf, sizeof(p->errbuf),
"malloc: %s", pcap_strerror(errno));
return (PCAP_ERROR);
}
**dlt_buffer = p->linktype;
return (1);
} else {
*dlt_buffer = (int*)calloc(sizeof(**dlt_buffer), p->dlt_count);
if (*dlt_buffer == NULL) {
(void)snprintf(p->errbuf, sizeof(p->errbuf),
"malloc: %s", pcap_strerror(errno));
return (PCAP_ERROR);
}
(void)memcpy(*dlt_buffer, p->dlt_list,
sizeof(**dlt_buffer) * p->dlt_count);
return (p->dlt_count);
}
}
/*
* In Windows, you might have a library built with one version of the
* C runtime library and an application built with another version of
* the C runtime library, which means that the library might use one
* version of malloc() and free() and the application might use another
* version of malloc() and free(). If so, that means something
* allocated by the library cannot be freed by the application, so we
* need to have a pcap_free_datalinks() routine to free up the list
* allocated by pcap_list_datalinks(), even though it's just a wrapper
* around free().
*/
void
pcap_free_datalinks(int *dlt_list)
{
free(dlt_list);
}
int
pcap_set_datalink(pcap_t *p, int dlt)
{
int i;
const char *dlt_name;
if (p->dlt_count == 0 || p->set_datalink_op == NULL) {
/*
* We couldn't fetch the list of DLTs, or we don't
* have a "set datalink" operation, which means
* this platform doesn't support changing the
* DLT for an interface. Check whether the new
* DLT is the one this interface supports.
*/
if (p->linktype != dlt)
goto unsupported;
/*
* It is, so there's nothing we need to do here.
*/
return (0);
}
for (i = 0; i < p->dlt_count; i++)
if (p->dlt_list[i] == dlt)
break;
if (i >= p->dlt_count)
goto unsupported;
if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB &&
dlt == DLT_DOCSIS) {
/*
* This is presumably an Ethernet device, as the first
* link-layer type it offers is DLT_EN10MB, and the only
* other type it offers is DLT_DOCSIS. That means that
* we can't tell the driver to supply DOCSIS link-layer
* headers - we're just pretending that's what we're
* getting, as, presumably, we're capturing on a dedicated
* link to a Cisco Cable Modem Termination System, and
* it's putting raw DOCSIS frames on the wire inside low-level
* Ethernet framing.
*/
p->linktype = dlt;
return (0);
}
if (p->set_datalink_op(p, dlt) == -1)
return (-1);
p->linktype = dlt;
return (0);
unsupported:
dlt_name = pcap_datalink_val_to_name(dlt);
if (dlt_name != NULL) {
(void) snprintf(p->errbuf, sizeof(p->errbuf),
"%s is not one of the DLTs supported by this device",
dlt_name);
} else {
(void) snprintf(p->errbuf, sizeof(p->errbuf),
"DLT %d is not one of the DLTs supported by this device",
dlt);
}
return (-1);
}
/*
* This array is designed for mapping upper and lower case letter
* together for a case independent comparison. The mappings are
* based upon ascii character sequences.
*/
static const u_char charmap[] = {
(u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003',
(u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007',
(u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013',
(u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017',
(u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023',
(u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027',
(u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033',
(u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037',
(u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043',
(u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047',
(u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053',
(u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057',
(u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063',
(u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067',
(u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073',
(u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077',
(u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143',
(u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
(u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
(u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
(u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
(u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
(u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133',
(u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137',
(u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143',
(u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
(u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
(u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
(u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
(u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
(u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173',
(u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177',
(u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203',
(u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207',
(u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213',
(u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217',
(u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223',
(u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227',
(u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233',
(u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237',
(u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243',
(u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247',
(u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253',
(u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257',
(u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263',
(u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267',
(u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273',
(u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277',
(u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343',
(u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
(u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
(u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
(u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
(u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
(u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333',
(u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337',
(u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343',
(u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
(u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
(u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
(u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
(u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
(u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373',
(u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377',
};
int
pcap_strcasecmp(const char *s1, const char *s2)
{
register const u_char *cm = charmap,
*us1 = (const u_char *)s1,
*us2 = (const u_char *)s2;
while (cm[*us1] == cm[*us2++])
if (*us1++ == '\0')
return(0);
return (cm[*us1] - cm[*--us2]);
}
struct dlt_choice {
const char *name;
const char *description;
int dlt;
};
#define DLT_CHOICE(code, description) { #code, description, code }
#define DLT_CHOICE_SENTINEL { NULL, NULL, 0 }
static struct dlt_choice dlt_choices[] = {
DLT_CHOICE(DLT_NULL, "BSD loopback"),
DLT_CHOICE(DLT_EN10MB, "Ethernet"),
DLT_CHOICE(DLT_IEEE802, "Token ring"),
DLT_CHOICE(DLT_ARCNET, "BSD ARCNET"),
DLT_CHOICE(DLT_SLIP, "SLIP"),
DLT_CHOICE(DLT_PPP, "PPP"),
DLT_CHOICE(DLT_FDDI, "FDDI"),
DLT_CHOICE(DLT_ATM_RFC1483, "RFC 1483 LLC-encapsulated ATM"),
DLT_CHOICE(DLT_RAW, "Raw IP"),
DLT_CHOICE(DLT_SLIP_BSDOS, "BSD/OS SLIP"),
DLT_CHOICE(DLT_PPP_BSDOS, "BSD/OS PPP"),
DLT_CHOICE(DLT_ATM_CLIP, "Linux Classical IP-over-ATM"),
DLT_CHOICE(DLT_PPP_SERIAL, "PPP over serial"),
DLT_CHOICE(DLT_PPP_ETHER, "PPPoE"),
DLT_CHOICE(DLT_SYMANTEC_FIREWALL, "Symantec Firewall"),
DLT_CHOICE(DLT_C_HDLC, "Cisco HDLC"),
DLT_CHOICE(DLT_IEEE802_11, "802.11"),
DLT_CHOICE(DLT_FRELAY, "Frame Relay"),
DLT_CHOICE(DLT_LOOP, "OpenBSD loopback"),
DLT_CHOICE(DLT_ENC, "OpenBSD encapsulated IP"),
DLT_CHOICE(DLT_LINUX_SLL, "Linux cooked"),
DLT_CHOICE(DLT_LTALK, "Localtalk"),
DLT_CHOICE(DLT_PFLOG, "OpenBSD pflog file"),
DLT_CHOICE(DLT_PFSYNC, "Packet filter state syncing"),
DLT_CHOICE(DLT_PRISM_HEADER, "802.11 plus Prism header"),
DLT_CHOICE(DLT_IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"),
DLT_CHOICE(DLT_SUNATM, "Sun raw ATM"),
DLT_CHOICE(DLT_IEEE802_11_RADIO, "802.11 plus radiotap header"),
DLT_CHOICE(DLT_ARCNET_LINUX, "Linux ARCNET"),
DLT_CHOICE(DLT_JUNIPER_MLPPP, "Juniper Multi-Link PPP"),
DLT_CHOICE(DLT_JUNIPER_MLFR, "Juniper Multi-Link Frame Relay"),
DLT_CHOICE(DLT_JUNIPER_ES, "Juniper Encryption Services PIC"),
DLT_CHOICE(DLT_JUNIPER_GGSN, "Juniper GGSN PIC"),
DLT_CHOICE(DLT_JUNIPER_MFR, "Juniper FRF.16 Frame Relay"),
DLT_CHOICE(DLT_JUNIPER_ATM2, "Juniper ATM2 PIC"),
DLT_CHOICE(DLT_JUNIPER_SERVICES, "Juniper Advanced Services PIC"),
DLT_CHOICE(DLT_JUNIPER_ATM1, "Juniper ATM1 PIC"),
DLT_CHOICE(DLT_APPLE_IP_OVER_IEEE1394, "Apple IP-over-IEEE 1394"),
DLT_CHOICE(DLT_MTP2_WITH_PHDR, "SS7 MTP2 with Pseudo-header"),
DLT_CHOICE(DLT_MTP2, "SS7 MTP2"),
DLT_CHOICE(DLT_MTP3, "SS7 MTP3"),
DLT_CHOICE(DLT_SCCP, "SS7 SCCP"),
DLT_CHOICE(DLT_DOCSIS, "DOCSIS"),
DLT_CHOICE(DLT_LINUX_IRDA, "Linux IrDA"),
DLT_CHOICE(DLT_IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"),
DLT_CHOICE(DLT_JUNIPER_MONITOR, "Juniper Passive Monitor PIC"),
DLT_CHOICE(DLT_BACNET_MS_TP, "BACnet MS/TP"),
DLT_CHOICE(DLT_PPP_PPPD, "PPP for pppd, with direction flag"),
DLT_CHOICE(DLT_JUNIPER_PPPOE, "Juniper PPPoE"),
DLT_CHOICE(DLT_JUNIPER_PPPOE_ATM, "Juniper PPPoE/ATM"),
DLT_CHOICE(DLT_GPRS_LLC, "GPRS LLC"),
DLT_CHOICE(DLT_GPF_T, "GPF-T"),
DLT_CHOICE(DLT_GPF_F, "GPF-F"),
DLT_CHOICE(DLT_JUNIPER_PIC_PEER, "Juniper PIC Peer"),
DLT_CHOICE(DLT_ERF_ETH, "Ethernet with Endace ERF header"),
DLT_CHOICE(DLT_ERF_POS, "Packet-over-SONET with Endace ERF header"),
DLT_CHOICE(DLT_LINUX_LAPD, "Linux vISDN LAPD"),
DLT_CHOICE(DLT_JUNIPER_ETHER, "Juniper Ethernet"),
DLT_CHOICE(DLT_JUNIPER_PPP, "Juniper PPP"),
DLT_CHOICE(DLT_JUNIPER_FRELAY, "Juniper Frame Relay"),
DLT_CHOICE(DLT_JUNIPER_CHDLC, "Juniper C-HDLC"),
DLT_CHOICE(DLT_MFR, "FRF.16 Frame Relay"),
DLT_CHOICE(DLT_JUNIPER_VP, "Juniper Voice PIC"),
DLT_CHOICE(DLT_A429, "Arinc 429"),
DLT_CHOICE(DLT_A653_ICM, "Arinc 653 Interpartition Communication"),
DLT_CHOICE(DLT_USB, "USB"),
DLT_CHOICE(DLT_BLUETOOTH_HCI_H4, "Bluetooth HCI UART transport layer"),
DLT_CHOICE(DLT_IEEE802_16_MAC_CPS, "IEEE 802.16 MAC Common Part Sublayer"),
DLT_CHOICE(DLT_USB_LINUX, "USB with Linux header"),
DLT_CHOICE(DLT_CAN20B, "Controller Area Network (CAN) v. 2.0B"),
DLT_CHOICE(DLT_IEEE802_15_4_LINUX, "IEEE 802.15.4 with Linux padding"),
DLT_CHOICE(DLT_PPI, "Per-Packet Information"),
DLT_CHOICE(DLT_IEEE802_16_MAC_CPS_RADIO, "IEEE 802.16 MAC Common Part Sublayer plus radiotap header"),
DLT_CHOICE(DLT_JUNIPER_ISM, "Juniper Integrated Service Module"),
DLT_CHOICE(DLT_IEEE802_15_4, "IEEE 802.15.4 with FCS"),
DLT_CHOICE(DLT_SITA, "SITA pseudo-header"),
DLT_CHOICE(DLT_ERF, "Endace ERF header"),
DLT_CHOICE(DLT_RAIF1, "Ethernet with u10 Networks pseudo-header"),
DLT_CHOICE(DLT_IPMB, "IPMB"),
DLT_CHOICE(DLT_JUNIPER_ST, "Juniper Secure Tunnel"),
DLT_CHOICE(DLT_BLUETOOTH_HCI_H4_WITH_PHDR, "Bluetooth HCI UART transport layer plus pseudo-header"),
DLT_CHOICE(DLT_AX25_KISS, "AX.25 with KISS header"),
DLT_CHOICE(DLT_IEEE802_15_4_NONASK_PHY, "IEEE 802.15.4 with non-ASK PHY data"),
DLT_CHOICE(DLT_MPLS, "MPLS with label as link-layer header"),
DLT_CHOICE(DLT_USB_LINUX_MMAPPED, "USB with padded Linux header"),
DLT_CHOICE(DLT_DECT, "DECT"),
DLT_CHOICE(DLT_AOS, "AOS Space Data Link protocol"),
DLT_CHOICE(DLT_WIHART, "Wireless HART"),
DLT_CHOICE(DLT_FC_2, "Fibre Channel FC-2"),
DLT_CHOICE(DLT_FC_2_WITH_FRAME_DELIMS, "Fibre Channel FC-2 with frame delimiters"),
DLT_CHOICE(DLT_IPNET, "Solaris ipnet"),
DLT_CHOICE(DLT_CAN_SOCKETCAN, "CAN-bus with SocketCAN headers"),
DLT_CHOICE(DLT_IPV4, "Raw IPv4"),
DLT_CHOICE(DLT_IPV6, "Raw IPv6"),
DLT_CHOICE(DLT_IEEE802_15_4_NOFCS, "IEEE 802.15.4 without FCS"),
DLT_CHOICE(DLT_JUNIPER_VS, "Juniper Virtual Server"),
DLT_CHOICE(DLT_JUNIPER_SRX_E2E, "Juniper SRX E2E"),
DLT_CHOICE(DLT_JUNIPER_FIBRECHANNEL, "Juniper Fibre Channel"),
DLT_CHOICE(DLT_DVB_CI, "DVB-CI"),
DLT_CHOICE(DLT_JUNIPER_ATM_CEMIC, "Juniper ATM CEMIC"),
DLT_CHOICE(DLT_NFLOG, "Linux netfilter log messages"),
DLT_CHOICE(DLT_NETANALYZER, "Ethernet with Hilscher netANALYZER pseudo-header"),
DLT_CHOICE(DLT_NETANALYZER_TRANSPARENT, "Ethernet with Hilscher netANALYZER pseudo-header and with preamble and SFD"),
DLT_CHOICE(DLT_IPOIB, "RFC 4391 IP-over-Infiniband"),
DLT_CHOICE(DLT_DBUS, "D-Bus"),
DLT_CHOICE_SENTINEL
};
int
pcap_datalink_name_to_val(const char *name)
{
int i;
for (i = 0; dlt_choices[i].name != NULL; i++) {
if (pcap_strcasecmp(dlt_choices[i].name + sizeof("DLT_") - 1,
name) == 0)
return (dlt_choices[i].dlt);
}
return (-1);
}
const char *
pcap_datalink_val_to_name(int dlt)
{
int i;
for (i = 0; dlt_choices[i].name != NULL; i++) {
if (dlt_choices[i].dlt == dlt)
return (dlt_choices[i].name + sizeof("DLT_") - 1);
}
return (NULL);
}
const char *
pcap_datalink_val_to_description(int dlt)
{
int i;
for (i = 0; dlt_choices[i].name != NULL; i++) {
if (dlt_choices[i].dlt == dlt)
return (dlt_choices[i].description);
}
return (NULL);
}
struct tstamp_type_choice {
const char *name;
const char *description;
int type;
};
static struct tstamp_type_choice tstamp_type_choices[] = {
{ "host", "Host", PCAP_TSTAMP_HOST },
{ "host_lowprec", "Host, low precision", PCAP_TSTAMP_HOST_LOWPREC },
{ "host_hiprec", "Host, high precision", PCAP_TSTAMP_HOST_HIPREC },
{ "adapter", "Adapter", PCAP_TSTAMP_ADAPTER },
{ "adapter_unsynced", "Adapter, not synced with system time", PCAP_TSTAMP_ADAPTER_UNSYNCED },
{ NULL, NULL, 0 }
};
int
pcap_tstamp_type_name_to_val(const char *name)
{
int i;
for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
if (pcap_strcasecmp(tstamp_type_choices[i].name, name) == 0)
return (tstamp_type_choices[i].type);
}
return (PCAP_ERROR);
}
const char *
pcap_tstamp_type_val_to_name(int tstamp_type)
{
int i;
for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
if (tstamp_type_choices[i].type == tstamp_type)
return (tstamp_type_choices[i].name);
}
return (NULL);
}
const char *
pcap_tstamp_type_val_to_description(int tstamp_type)
{
int i;
for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
if (tstamp_type_choices[i].type == tstamp_type)
return (tstamp_type_choices[i].description);
}
return (NULL);
}
int
pcap_snapshot(pcap_t *p)
{
if (!p->activated)
return (PCAP_ERROR_NOT_ACTIVATED);
return (p->snapshot);
}
int
pcap_is_swapped(pcap_t *p)
{
if (!p->activated)
return (PCAP_ERROR_NOT_ACTIVATED);
return (p->swapped);
}
int
pcap_major_version(pcap_t *p)
{
if (!p->activated)
return (PCAP_ERROR_NOT_ACTIVATED);
return (p->version_major);
}
int
pcap_minor_version(pcap_t *p)
{
if (!p->activated)
return (PCAP_ERROR_NOT_ACTIVATED);
return (p->version_minor);
}
FILE *
pcap_file(pcap_t *p)
{
return (p->rfile);
}
int
pcap_fileno(pcap_t *p)
{
#ifndef WIN32
return (p->fd);
#else
if (p->adapter != NULL)
return ((int)(DWORD)p->adapter->hFile);
else
return (PCAP_ERROR);
#endif
}
#if !defined(WIN32) && !defined(MSDOS)
int
pcap_get_selectable_fd(pcap_t *p)
{
return (p->selectable_fd);
}
#endif
void
pcap_perror(pcap_t *p, char *prefix)
{
fprintf(stderr, "%s: %s\n", prefix, p->errbuf);
}
char *
pcap_geterr(pcap_t *p)
{
return (p->errbuf);
}
int
pcap_getnonblock(pcap_t *p, char *errbuf)
{
int ret;
ret = p->getnonblock_op(p, errbuf);
if (ret == -1) {
/*
* In case somebody depended on the bug wherein
* the error message was put into p->errbuf
* by pcap_getnonblock_fd().
*/
strlcpy(p->errbuf, errbuf, PCAP_ERRBUF_SIZE);
}
return (ret);
}
/*
* Get the current non-blocking mode setting, under the assumption that
* it's just the standard POSIX non-blocking flag.
*
* We don't look at "p->nonblock", in case somebody tweaked the FD
* directly.
*/
#if !defined(WIN32) && !defined(MSDOS)
int
pcap_getnonblock_fd(pcap_t *p, char *errbuf)
{
int fdflags;
fdflags = fcntl(p->fd, F_GETFL, 0);
if (fdflags == -1) {
snprintf(errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s",
pcap_strerror(errno));
return (-1);
}
if (fdflags & O_NONBLOCK)
return (1);
else
return (0);
}
#endif
int
pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf)
{
int ret;
ret = p->setnonblock_op(p, nonblock, errbuf);
if (ret == -1) {
/*
* In case somebody depended on the bug wherein
* the error message was put into p->errbuf
* by pcap_setnonblock_fd().
*/
strlcpy(p->errbuf, errbuf, PCAP_ERRBUF_SIZE);
}
return (ret);
}
#if !defined(WIN32) && !defined(MSDOS)
/*
* Set non-blocking mode, under the assumption that it's just the
* standard POSIX non-blocking flag. (This can be called by the
* per-platform non-blocking-mode routine if that routine also
* needs to do some additional work.)
*/
int
pcap_setnonblock_fd(pcap_t *p, int nonblock, char *errbuf)
{
int fdflags;
fdflags = fcntl(p->fd, F_GETFL, 0);
if (fdflags == -1) {
snprintf(errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s",
pcap_strerror(errno));
return (-1);
}
if (nonblock)
fdflags |= O_NONBLOCK;
else
fdflags &= ~O_NONBLOCK;
if (fcntl(p->fd, F_SETFL, fdflags) == -1) {
snprintf(errbuf, PCAP_ERRBUF_SIZE, "F_SETFL: %s",
pcap_strerror(errno));
return (-1);
}
return (0);
}
#endif
#ifdef WIN32
/*
* Generate a string for the last Win32-specific error (i.e. an error generated when
* calling a Win32 API).
* For errors occurred during standard C calls, we still use pcap_strerror()
*/
char *
pcap_win32strerror(void)
{
DWORD error;
static char errbuf[PCAP_ERRBUF_SIZE+1];
int errlen;
char *p;
error = GetLastError();
FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf,
PCAP_ERRBUF_SIZE, NULL);
/*
* "FormatMessage()" "helpfully" sticks CR/LF at the end of the
* message. Get rid of it.
*/
errlen = strlen(errbuf);
if (errlen >= 2) {
errbuf[errlen - 1] = '\0';
errbuf[errlen - 2] = '\0';
}
p = strchr(errbuf, '\0');
snprintf (p, sizeof(errbuf)-(p-errbuf), " (%lu)", error);
return (errbuf);
}
#endif
/*
* Generate error strings for PCAP_ERROR_ and PCAP_WARNING_ values.
*/
const char *
pcap_statustostr(int errnum)
{
static char ebuf[15+10+1];
switch (errnum) {
case PCAP_WARNING:
return("Generic warning");
case PCAP_WARNING_TSTAMP_TYPE_NOTSUP:
return ("That type of time stamp is not supported by that device");
case PCAP_WARNING_PROMISC_NOTSUP:
return ("That device doesn't support promiscuous mode");
case PCAP_ERROR:
return("Generic error");
case PCAP_ERROR_BREAK:
return("Loop terminated by pcap_breakloop");
case PCAP_ERROR_NOT_ACTIVATED:
return("The pcap_t has not been activated");
case PCAP_ERROR_ACTIVATED:
return ("The setting can't be changed after the pcap_t is activated");
case PCAP_ERROR_NO_SUCH_DEVICE:
return ("No such device exists");
case PCAP_ERROR_RFMON_NOTSUP:
return ("That device doesn't support monitor mode");
case PCAP_ERROR_NOT_RFMON:
return ("That operation is supported only in monitor mode");
case PCAP_ERROR_PERM_DENIED:
return ("You don't have permission to capture on that device");
case PCAP_ERROR_IFACE_NOT_UP:
return ("That device is not up");
case PCAP_ERROR_CANTSET_TSTAMP_TYPE:
return ("That device doesn't support setting the time stamp type");
case PCAP_ERROR_PROMISC_PERM_DENIED:
return ("You don't have permission to capture in promiscuous mode on that device");
case PCAP_ERROR_TSTAMP_PRECISION_NOTSUP:
return ("That device doesn't support that time stamp precision");
}
(void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
return(ebuf);
}
/*
* Not all systems have strerror().
*/
const char *
pcap_strerror(int errnum)
{
#ifdef HAVE_STRERROR
return (strerror(errnum));
#else
extern int sys_nerr;
extern const char *const sys_errlist[];
static char ebuf[15+10+1];
if ((unsigned int)errnum < sys_nerr)
return ((char *)sys_errlist[errnum]);
(void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
return(ebuf);
#endif
}
int
pcap_setfilter(pcap_t *p, struct bpf_program *fp)
{
return (p->setfilter_op(p, fp));
}
/*
* Set direction flag, which controls whether we accept only incoming
* packets, only outgoing packets, or both.
* Note that, depending on the platform, some or all direction arguments
* might not be supported.
*/
int
pcap_setdirection(pcap_t *p, pcap_direction_t d)
{
if (p->setdirection_op == NULL) {
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
"Setting direction is not implemented on this platform");
return (-1);
} else
return (p->setdirection_op(p, d));
}
int
pcap_stats(pcap_t *p, struct pcap_stat *ps)
{
return (p->stats_op(p, ps));
}
static int
pcap_stats_dead(pcap_t *p, struct pcap_stat *ps _U_)
{
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
"Statistics aren't available from a pcap_open_dead pcap_t");
return (-1);
}
#ifdef WIN32
int
pcap_setbuff(pcap_t *p, int dim)
{
return (p->setbuff_op(p, dim));
}
static int
pcap_setbuff_dead(pcap_t *p, int dim)
{
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
"The kernel buffer size cannot be set on a pcap_open_dead pcap_t");
return (-1);
}
int
pcap_setmode(pcap_t *p, int mode)
{
return (p->setmode_op(p, mode));
}
static int
pcap_setmode_dead(pcap_t *p, int mode)
{
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
"impossible to set mode on a pcap_open_dead pcap_t");
return (-1);
}
int
pcap_setmintocopy(pcap_t *p, int size)
{
return (p->setmintocopy_op(p, size));
}
Adapter *
pcap_get_adapter(pcap_t *p)
{
return (p->getadapter_op(p));
}
static int
pcap_setmintocopy_dead(pcap_t *p, int size)
{
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
"The mintocopy parameter cannot be set on a pcap_open_dead pcap_t");
return (-1);
}
#endif
/*
* On some platforms, we need to clean up promiscuous or monitor mode
* when we close a device - and we want that to happen even if the
* application just exits without explicitl closing devices.
* On those platforms, we need to register a "close all the pcaps"
* routine to be called when we exit, and need to maintain a list of
* pcaps that need to be closed to clean up modes.
*
* XXX - not thread-safe.
*/
/*
* List of pcaps on which we've done something that needs to be
* cleaned up.
* If there are any such pcaps, we arrange to call "pcap_close_all()"
* when we exit, and have it close all of them.
*/
static struct pcap *pcaps_to_close;
/*
* TRUE if we've already called "atexit()" to cause "pcap_close_all()" to
* be called on exit.
*/
static int did_atexit;
static void
pcap_close_all(void)
{
struct pcap *handle;
while ((handle = pcaps_to_close) != NULL)
pcap_close(handle);
}
int
pcap_do_addexit(pcap_t *p)
{
/*
* If we haven't already done so, arrange to have
* "pcap_close_all()" called when we exit.
*/
if (!did_atexit) {
if (atexit(pcap_close_all) == -1) {
/*
* "atexit()" failed; let our caller know.
*/
strncpy(p->errbuf, "atexit failed",
PCAP_ERRBUF_SIZE);
return (0);
}
did_atexit = 1;
}
return (1);
}
void
pcap_add_to_pcaps_to_close(pcap_t *p)
{
p->next = pcaps_to_close;
pcaps_to_close = p;
}
void
pcap_remove_from_pcaps_to_close(pcap_t *p)
{
pcap_t *pc, *prevpc;
for (pc = pcaps_to_close, prevpc = NULL; pc != NULL;
prevpc = pc, pc = pc->next) {
if (pc == p) {
/*
* Found it. Remove it from the list.
*/
if (prevpc == NULL) {
/*
* It was at the head of the list.
*/
pcaps_to_close = pc->next;
} else {
/*
* It was in the middle of the list.
*/
prevpc->next = pc->next;
}
break;
}
}
}
void
pcap_cleanup_live_common(pcap_t *p)
{
if (p->buffer != NULL) {
free(p->buffer);
p->buffer = NULL;
}
if (p->dlt_list != NULL) {
free(p->dlt_list);
p->dlt_list = NULL;
p->dlt_count = 0;
}
if (p->tstamp_type_list != NULL) {
free(p->tstamp_type_list);
p->tstamp_type_list = NULL;
p->tstamp_type_count = 0;
}
if (p->tstamp_precision_list != NULL) {
free(p->tstamp_precision_list);
p->tstamp_precision_list = NULL;
p->tstamp_precision_count = 0;
}
pcap_freecode(&p->fcode);
#if !defined(WIN32) && !defined(MSDOS)
if (p->fd >= 0) {
close(p->fd);
p->fd = -1;
}
p->selectable_fd = -1;
#endif
}
static void
pcap_cleanup_dead(pcap_t *p _U_)
{
/* Nothing to do. */
}
pcap_t *
pcap_open_dead_with_tstamp_precision(int linktype, int snaplen, u_int precision)
{
pcap_t *p;
switch (precision) {
case PCAP_TSTAMP_PRECISION_MICRO:
case PCAP_TSTAMP_PRECISION_NANO:
break;
default:
return NULL;
}
p = malloc(sizeof(*p));
if (p == NULL)
return NULL;
memset (p, 0, sizeof(*p));
p->snapshot = snaplen;
p->linktype = linktype;
p->opt.tstamp_precision = precision;
p->stats_op = pcap_stats_dead;
#ifdef WIN32
p->setbuff_op = pcap_setbuff_dead;
p->setmode_op = pcap_setmode_dead;
p->setmintocopy_op = pcap_setmintocopy_dead;
#endif
p->cleanup_op = pcap_cleanup_dead;
p->activated = 1;
return (p);
}
pcap_t *
pcap_open_dead(int linktype, int snaplen)
{
return (pcap_open_dead_with_tstamp_precision(linktype, snaplen,
PCAP_TSTAMP_PRECISION_MICRO));
}
/*
* API compatible with WinPcap's "send a packet" routine - returns -1
* on error, 0 otherwise.
*
* XXX - what if we get a short write?
*/
int
pcap_sendpacket(pcap_t *p, const u_char *buf, int size)
{
if (p->inject_op(p, buf, size) == -1)
return (-1);
return (0);
}
/*
* API compatible with OpenBSD's "send a packet" routine - returns -1 on
* error, number of bytes written otherwise.
*/
int
pcap_inject(pcap_t *p, const void *buf, size_t size)
{
return (p->inject_op(p, buf, size));
}
void
pcap_close(pcap_t *p)
{
if (p->opt.source != NULL)
free(p->opt.source);
p->cleanup_op(p);
free(p);
}
/*
* Given a BPF program, a pcap_pkthdr structure for a packet, and the raw
* data for the packet, check whether the packet passes the filter.
* Returns the return value of the filter program, which will be zero if
* the packet doesn't pass and non-zero if the packet does pass.
*/
int
pcap_offline_filter(const struct bpf_program *fp, const struct pcap_pkthdr *h,
const u_char *pkt)
{
const struct bpf_insn *fcode = fp->bf_insns;
if (fcode != NULL)
return (bpf_filter(fcode, pkt, h->len, h->caplen));
else
return (0);
}
/*
* We make the version string static, and return a pointer to it, rather
* than exporting the version string directly. On at least some UNIXes,
* if you import data from a shared library into an program, the data is
* bound into the program binary, so if the string in the version of the
* library with which the program was linked isn't the same as the
* string in the version of the library with which the program is being
* run, various undesirable things may happen (warnings, the string
* being the one from the version of the library with which the program
* was linked, or even weirder things, such as the string being the one
* from the library but being truncated).
*/
#ifdef HAVE_VERSION_H
#include "version.h"
#else
static const char pcap_version_string[] = "libpcap version 1.x.y";
#endif
#ifdef WIN32
/*
* XXX - it'd be nice if we could somehow generate the WinPcap and libpcap
* version numbers when building WinPcap. (It'd be nice to do so for
* the packet.dll version number as well.)
*/
static const char wpcap_version_string[] = "4.0";
static const char pcap_version_string_fmt[] =
"WinPcap version %s, based on %s";
static const char pcap_version_string_packet_dll_fmt[] =
"WinPcap version %s (packet.dll version %s), based on %s";
static char *full_pcap_version_string;
const char *
pcap_lib_version(void)
{
char *packet_version_string;
size_t full_pcap_version_string_len;
if (full_pcap_version_string == NULL) {
/*
* Generate the version string.
*/
packet_version_string = PacketGetVersion();
if (strcmp(wpcap_version_string, packet_version_string) == 0) {
/*
* WinPcap version string and packet.dll version
* string are the same; just report the WinPcap
* version.
*/
full_pcap_version_string_len =
(sizeof pcap_version_string_fmt - 4) +
strlen(wpcap_version_string) +
strlen(pcap_version_string);
full_pcap_version_string =
malloc(full_pcap_version_string_len);
if (full_pcap_version_string == NULL)
return (NULL);
sprintf(full_pcap_version_string,
pcap_version_string_fmt, wpcap_version_string,
pcap_version_string);
} else {
/*
* WinPcap version string and packet.dll version
* string are different; that shouldn't be the
* case (the two libraries should come from the
* same version of WinPcap), so we report both
* versions.
*/
full_pcap_version_string_len =
(sizeof pcap_version_string_packet_dll_fmt - 6) +
strlen(wpcap_version_string) +
strlen(packet_version_string) +
strlen(pcap_version_string);
full_pcap_version_string = malloc(full_pcap_version_string_len);
if (full_pcap_version_string == NULL)
return (NULL);
sprintf(full_pcap_version_string,
pcap_version_string_packet_dll_fmt,
wpcap_version_string, packet_version_string,
pcap_version_string);
}
}
return (full_pcap_version_string);
}
#elif defined(MSDOS)
static char *full_pcap_version_string;
const char *
pcap_lib_version (void)
{
char *packet_version_string;
size_t full_pcap_version_string_len;
static char dospfx[] = "DOS-";
if (full_pcap_version_string == NULL) {
/*
* Generate the version string.
*/
full_pcap_version_string_len =
sizeof dospfx + strlen(pcap_version_string);
full_pcap_version_string =
malloc(full_pcap_version_string_len);
if (full_pcap_version_string == NULL)
return (NULL);
strcpy(full_pcap_version_string, dospfx);
strcat(full_pcap_version_string, pcap_version_string);
}
return (full_pcap_version_string);
}
#else /* UN*X */
const char *
pcap_lib_version(void)
{
return (pcap_version_string);
}
#endif