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/* capture-pcap-util-unix.c
* UN*X-specific utility routines for packet capture
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <glib.h>
#ifdef HAVE_LIBPCAP
#include <pcap.h>
#ifdef __APPLE__
#include <dlfcn.h>
#endif
#ifndef HAVE_PCAP_FINDALLDEVS
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
/*
* Keep Digital UNIX happy when including <net/if.h>.
*/
struct mbuf;
struct rtentry;
#include <net/if.h>
#ifdef HAVE_SYS_SOCKIO_H
# include <sys/sockio.h>
#endif
#endif /* HAVE_PCAP_FINDALLDEVS */
#ifdef HAVE_LIBCAP
# include <sys/capability.h>
#endif
#include "caputils/capture_ifinfo.h"
#include "caputils/capture-pcap-util.h"
#include "caputils/capture-pcap-util-int.h"
#ifdef HAVE_PCAP_REMOTE
GList *
get_remote_interface_list(const char *hostname, const char *port,
int auth_type, const char *username,
const char *passwd, int *err, char **err_str)
{
struct pcap_rmtauth auth;
char source[PCAP_BUF_SIZE];
char errbuf[PCAP_ERRBUF_SIZE];
GList *result;
if (pcap_createsrcstr(source, PCAP_SRC_IFREMOTE, hostname, port,
NULL, errbuf) == -1) {
*err = CANT_GET_INTERFACE_LIST;
if (err_str != NULL)
*err_str = cant_get_if_list_error_message(errbuf);
return NULL;
}
auth.type = auth_type;
auth.username = g_strdup(username);
auth.password = g_strdup(passwd);
result = get_interface_list_findalldevs_ex(source, &auth, err, err_str);
g_free(auth.username);
g_free(auth.password);
return result;
}
#endif
#ifdef HAVE_PCAP_FINDALLDEVS
GList *
get_interface_list(int *err, char **err_str)
{
return get_interface_list_findalldevs(err, err_str);
}
#else /* HAVE_PCAP_FINDALLDEVS */
struct search_user_data {
char *name;
if_info_t *if_info;
};
static void
search_for_if_cb(gpointer data, gpointer user_data)
{
struct search_user_data *search_user_data = (struct search_user_data*)user_data;
if_info_t *if_info = (if_info_t *)data;
if (strcmp(if_info->name, search_user_data->name) == 0)
search_user_data->if_info = if_info;
}
GList *
get_interface_list(int *err, char **err_str)
{
GList *il = NULL;
gint nonloopback_pos = 0;
struct ifreq *ifr, *last;
struct ifconf ifc;
struct ifreq ifrflags;
int sock = socket(AF_INET, SOCK_DGRAM, 0);
struct search_user_data user_data;
pcap_t *pch;
int len, lastlen;
char *buf;
if_info_t *if_info;
char errbuf[PCAP_ERRBUF_SIZE];
gboolean loopback;
if (sock < 0) {
*err = CANT_GET_INTERFACE_LIST;
if (err_str != NULL) {
*err_str = g_strdup_printf(
"Can't get list of interfaces: error opening socket: %s",
g_strerror(errno));
}
return NULL;
}
/*
* This code came from: W. Richard Stevens: "UNIX Network Programming",
* Networking APIs: Sockets and XTI, Vol 1, page 434.
*/
lastlen = 0;
len = 100 * sizeof(struct ifreq);
for ( ; ; ) {
buf = (char *)g_malloc(len);
ifc.ifc_len = len;
ifc.ifc_buf = buf;
memset (buf, 0, len);
if (ioctl(sock, SIOCGIFCONF, &ifc) < 0) {
if (errno != EINVAL || lastlen != 0) {
if (err_str != NULL) {
*err_str = g_strdup_printf(
"Can't get list of interfaces: SIOCGIFCONF ioctl error: %s",
g_strerror(errno));
}
goto fail;
}
} else {
if ((unsigned int) ifc.ifc_len < sizeof(struct ifreq)) {
if (err_str != NULL) {
*err_str = g_strdup(
"Can't get list of interfaces: SIOCGIFCONF ioctl gave too small return buffer");
}
goto fail;
}
if (ifc.ifc_len == lastlen)
break; /* success, len has not changed */
lastlen = ifc.ifc_len;
}
len += 10 * sizeof(struct ifreq); /* increment */
g_free(buf);
}
ifr = (struct ifreq *) ifc.ifc_req;
last = (struct ifreq *) ((char *) ifr + ifc.ifc_len);
while (ifr < last) {
/*
* Skip entries that begin with "dummy", or that include
* a ":" (the latter are Solaris virtuals).
*/
if (strncmp(ifr->ifr_name, "dummy", 5) == 0 ||
strchr(ifr->ifr_name, ':') != NULL)
goto next;
/*
* If we already have this interface name on the list,
* don't add it, but, if we don't already have an IP
* address for it, add that address (SIOCGIFCONF returns,
* at least on BSD-flavored systems, one entry per
* interface *address*; if an interface has multiple
* addresses, we get multiple entries for it).
*/
user_data.name = ifr->ifr_name;
user_data.if_info = NULL;
g_list_foreach(il, search_for_if_cb, &user_data);
if (user_data.if_info != NULL) {
if_info_add_address(user_data.if_info, &ifr->ifr_addr);
goto next;
}
/*
* Get the interface flags.
*/
memset(&ifrflags, 0, sizeof ifrflags);
g_strlcpy(ifrflags.ifr_name, ifr->ifr_name,
sizeof ifrflags.ifr_name);
if (ioctl(sock, SIOCGIFFLAGS, (char *)&ifrflags) < 0) {
if (errno == ENXIO)
goto next;
if (err_str != NULL) {
*err_str = g_strdup_printf(
"Can't get list of interfaces: SIOCGIFFLAGS error getting flags for interface %s: %s",
ifr->ifr_name, g_strerror(errno));
}
goto fail;
}
/*
* Skip interfaces that aren't up.
*/
if (!(ifrflags.ifr_flags & IFF_UP))
goto next;
/*
* Skip interfaces that we can't open with "libpcap".
* Open with the minimum packet size - it appears that the
* IRIX SIOCSNOOPLEN "ioctl" may fail if the capture length
* supplied is too large, rather than just truncating it.
*/
pch = pcap_open_live(ifr->ifr_name, MIN_PACKET_SIZE, 0, 0,
errbuf);
if (pch == NULL)
goto next;
pcap_close(pch);
/*
* If it's a loopback interface, add it at the end of the
* list, otherwise add it after the last non-loopback
* interface, so all loopback interfaces go at the end - we
* don't want a loopback interface to be the default capture
* device unless there are no non-loopback devices.
*/
loopback = ((ifrflags.ifr_flags & IFF_LOOPBACK) ||
strncmp(ifr->ifr_name, "lo", 2) == 0);
if_info = if_info_new(ifr->ifr_name, NULL, loopback);
if_info_add_address(if_info, &ifr->ifr_addr);
if (loopback)
il = g_list_append(il, if_info);
else {
il = g_list_insert(il, if_info, nonloopback_pos);
/*
* Insert the next non-loopback interface after this
* one.
*/
nonloopback_pos++;
}
next:
#ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
ifr = (struct ifreq *) ((char *) ifr +
(ifr->ifr_addr.sa_len > sizeof(ifr->ifr_addr) ?
ifr->ifr_addr.sa_len : sizeof(ifr->ifr_addr)) +
IFNAMSIZ);
#else
ifr = (struct ifreq *) ((char *) ifr + sizeof(struct ifreq));
#endif
}
#ifdef linux
/*
* OK, maybe we have support for the "any" device, to do a cooked
* capture on all interfaces at once.
* Try opening it and, if that succeeds, add it to the end of
* the list of interfaces.
*/
pch = pcap_open_live("any", MIN_PACKET_SIZE, 0, 0, errbuf);
if (pch != NULL) {
/*
* It worked; we can use the "any" device.
*/
if_info = if_info_new("any",
"Pseudo-device that captures on all interfaces", FALSE);
il = g_list_insert(il, if_info, -1);
pcap_close(pch);
}
#endif
g_free(ifc.ifc_buf);
close(sock);
if (il == NULL) {
/*
* No interfaces found.
*/
*err = 0;
if (err_str != NULL)
*err_str = NULL;
}
return il;
fail:
if (il != NULL)
free_interface_list(il);
g_free(ifc.ifc_buf);
close(sock);
*err = CANT_GET_INTERFACE_LIST;
return NULL;
}
#endif /* HAVE_PCAP_FINDALLDEVS */
/*
* Get an error message string for a CANT_GET_INTERFACE_LIST error from
* "get_interface_list()".
*/
gchar *
cant_get_if_list_error_message(const char *err_str)
{
return g_strdup_printf("Can't get list of interfaces: %s", err_str);
}
#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
/*
* Request high-resolution time stamps.
*
* We don't check for errors - if this fails, we just live with boring old
* microsecond-resolution time stamps. The only errors pcap_set_tstamp_precision()
* is documenting as returning are PCAP_ERROR_TSTAMP_PRECISION_NOTSUP, which just
* means we can't do nanosecond precision on this adapter, in which case we
* just live with whatever resolution we get by default, and
* PCAP_ERROR_ACTIVATED, which shouldn't happen as we shouldn't call this
* after we've activated the pcap_t.
*/
void
request_high_resolution_timestamp(pcap_t *pcap_h)
{
#ifdef __APPLE__
/*
* On OS X, if you build with a newer SDK, pcap_set_tstamp_precision()
* is available, so the code will be built with it.
*
* However, if you then try to run on an older release that
* doesn't have pcap_set_tstamp_precision(), the dynamic linker
* will fail, as it won't find pcap_set_tstamp_precision().
*
* libpcap doesn't use OS X "weak linking" for new routines,
* so we can't just check whether a pointer to
* pcap_set_tstamp_precision() is null and, if it is, not
* call it. We have to, instead, use dlopen() to load
* libpcap, and dlsym() to find a pointer to pcap_set_tstamp_precision(),
* and if we find the pointer, call it.
*/
static gboolean initialized = FALSE;
static int (*p_pcap_set_tstamp_precision)(pcap_t *, int);
if (!initialized) {
p_pcap_set_tstamp_precision =
(int (*)(pcap_t *, int))
dlsym(RTLD_NEXT, "pcap_set_tstamp_precision");
initialized = TRUE;
}
if (p_pcap_set_tstamp_precision != NULL)
(*p_pcap_set_tstamp_precision)(pcap_h, PCAP_TSTAMP_PRECISION_NANO);
#else /* __APPLE__ */
/*
* On other UN*Xes we require that we be run on an OS version
* with a libpcap equal to or later than the version with which
* we were built.
*/
pcap_set_tstamp_precision(pcap_h, PCAP_TSTAMP_PRECISION_NANO);
#endif /* __APPLE__ */
}
/*
* Return TRUE if the pcap_t in question is set up for high-precision
* time stamps, FALSE otherwise.
*/
gboolean
have_high_resolution_timestamp(pcap_t *pcap_h)
{
#ifdef __APPLE__
/*
* See above.
*/
static gboolean initialized = FALSE;
static int (*p_pcap_get_tstamp_precision)(pcap_t *);
if (!initialized) {
p_pcap_get_tstamp_precision =
(int (*)(pcap_t *))
dlsym(RTLD_NEXT, "pcap_get_tstamp_precision");
initialized = TRUE;
}
if (p_pcap_get_tstamp_precision != NULL)
return (*p_pcap_get_tstamp_precision)(pcap_h) == PCAP_TSTAMP_PRECISION_NANO;
else
return FALSE; /* Can't get implies couldn't set */
#else /* __APPLE__ */
/*
* On other UN*Xes we require that we be run on an OS version
* with a libpcap equal to or later than the version with which
* we were built.
*/
return pcap_get_tstamp_precision(pcap_h) == PCAP_TSTAMP_PRECISION_NANO;
#endif /* __APPLE__ */
}
#endif /* HAVE_PCAP_SET_TSTAMP_PRECISION */
if_capabilities_t *
get_if_capabilities_local(interface_options *interface_opts, char **err_str)
{
#ifdef HAVE_PCAP_CREATE
return get_if_capabilities_pcap_create(interface_opts, err_str);
#else
return get_if_capabilities_pcap_open_live(interface_opts, err_str);
#endif
}
pcap_t *
open_capture_device_local(capture_options *capture_opts,
interface_options *interface_opts, int timeout,
char (*open_err_str)[PCAP_ERRBUF_SIZE])
{
/*
* We're not opening a remote device; use pcap_create() and
* pcap_activate() if we have them, so that we can set various
* options, otherwise use pcap_open_live().
*/
#ifdef HAVE_PCAP_CREATE
return open_capture_device_pcap_create(capture_opts,
interface_opts, timeout, open_err_str);
#else
return open_capture_device_pcap_open_live(interface_opts, timeout,
open_err_str);
#endif
}
/*
* Get the versions of libpcap, libpcap, and libnl with which we were
* compiled, and append them to a GString.
*/
void
get_compiled_caplibs_version(GString *str)
{
/*
* NOTE: in *some* flavors of UN*X, the data from a shared
* library might be linked into executable images that are
* linked with that shared library, in which case you could
* look at pcap_version[] to get the version with which
* the program was compiled.
*
* In other flavors of UN*X, that doesn't happen, so
* pcap_version[] gives you the version the program is
* running with, not the version it was built with, and,
* in at least some of them, if the length of a data item
* referred to by the executable - such as the pcap_version[]
* string - isn't the same in the version of the library
* with which the program was built and the version with
* which it was run, the run-time linker will complain,
* which is Not Good.
*
* So, for now, we just give up on reporting the version
* of libpcap with which we were compiled.
*/
g_string_append(str, "with libpcap");
/*
* XXX - these libraries are actually used only by dumpcap,
* but we mention them here so that a user reporting a bug
* can get information about dumpcap's libraries without
* having to run dumpcap.
*/
/* LIBCAP */
g_string_append(str, ", ");
#ifdef HAVE_LIBCAP
g_string_append(str, "with POSIX capabilities");
#ifdef _LINUX_CAPABILITY_VERSION
g_string_append(str, " (Linux)");
#endif /* _LINUX_CAPABILITY_VERSION */
#else /* HAVE_LIBCAP */
g_string_append(str, "without POSIX capabilities");
#endif /* HAVE_LIBCAP */
#ifdef __linux__
/* This is a Linux-specific library. */
/* LIBNL */
g_string_append(str, ", ");
#if defined(HAVE_LIBNL1)
g_string_append(str, "with libnl 1");
#elif defined(HAVE_LIBNL2)
g_string_append(str, "with libnl 2");
#elif defined(HAVE_LIBNL3)
g_string_append(str, "with libnl 3");
#else /* no libnl */
g_string_append(str, "without libnl");
#endif /* libnl version */
#endif /* __linux__ */
}
/*
* Append the version of libpcap with which we we're running to a GString.
*/
void
get_runtime_caplibs_version(GString *str)
{
g_string_append_printf(str, "with ");
#ifdef HAVE_PCAP_LIB_VERSION
g_string_append(str, pcap_lib_version());
#else
g_string_append(str, "libpcap (version unknown)");
#endif
}
#else /* HAVE_LIBPCAP */
/*
* Append an indication that we were not compiled with libpcap
* to a GString. Don't even bother mentioning the other
* libraries.
*/
void
get_compiled_caplibs_version(GString *str)
{
g_string_append(str, "without libpcap");
}
/*
* Don't append anything, as we weren't even compiled to use libpcap.
*/
void
get_runtime_caplibs_version(GString *str _U_)
{
}
#endif /* HAVE_LIBPCAP */
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
* :indentSize=8:tabSize=8:noTabs=false:
*/