wireshark/capture/capture-pcap-util.c
John Thacker 085fdd0208 CMake: Require libpcap 1.5 or later
Require libpcap 1.5 (released 2013-11-07) or later. This rules
out building with the WinPCAP SDK.

This leaves the only optional libpcap features as remote capturing
support (via pcap_open) and the the sampling options (which are
treated as remote options and only enabled if we have remote
capture support).

Add a comment about how the workaround for building on macOS with
a SDK which has pcap_set_tstamp_precision and running on an earlier
version whose system shared libpcap doesn't support it shouldn't
be needed anymore, because we only support running on new enough
macOS.

Fix #20261
2025-02-04 18:40:39 +00:00

2097 lines
58 KiB
C

/* capture-pcap-util.c
* Utility routines for packet capture
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#define WS_LOG_DOMAIN LOG_DOMAIN_CAPCHILD
#ifdef HAVE_LIBPCAP
#include <wireshark.h>
#include <stdlib.h>
#include <stdio.h>
#include <limits.h>
#include <string.h>
#include <sys/types.h>
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef __APPLE__
#include <dlfcn.h>
#endif
#include "ws_attributes.h"
/*
* Linux bonding devices mishandle unknown ioctls; they fail
* with ENODEV rather than ENOTSUP, EOPNOTSUPP, or ENOTTY,
* so pcap_can_set_rfmon() returns a "no such device" indication
* if we try to do SIOCGIWMODE on them.
*
* So, on Linux, we check for bonding devices, if we can, before
* trying pcap_can_set_rfmon(), as pcap_can_set_rfmon() will
* end up trying SIOCGIWMODE on the device if that ioctl exists.
*/
#if defined(__linux__)
#include <sys/ioctl.h>
/*
* If we're building for a Linux version that supports bonding,
* HAVE_BONDING will be defined.
*/
#ifdef HAVE_LINUX_SOCKIOS_H
#include <linux/sockios.h>
#endif
#ifdef HAVE_LINUX_IF_BONDING_H
#include <linux/if_bonding.h>
#endif
#if defined(BOND_INFO_QUERY_OLD) || defined(SIOCBONDINFOQUERY)
#define HAVE_BONDING
#endif
#endif /* defined(__linux__) */
#include "capture/capture_ifinfo.h"
#include "capture/capture-pcap-util.h"
#include "capture/capture-pcap-util-int.h"
#ifdef _WIN32
#include "capture/capture-wpcap.h"
#else
#define ws_pcap_findalldevs_ex pcap_findalldevs_ex
#endif
#include <wsutil/application_flavor.h>
#include <wsutil/file_util.h>
#include <wsutil/please_report_bug.h>
#include <wsutil/wslog.h>
#ifndef _WIN32
#include <netinet/in.h>
#endif
#ifdef _WIN32
#include "capture/capture_win_ifnames.h" /* windows friendly interface names */
#endif
#if defined(__FreeBSD__) || defined(__OpenBSD__)
/*
* Needed for the code to get a device description.
*/
#include <errno.h>
#include <net/if.h>
#include <sys/sockio.h>
#include <sys/ioctl.h>
#endif
/*
* Given an interface name, find the "friendly name" and interface
* type for the interface.
*/
#if defined(HAVE_MACOS_FRAMEWORKS)
#include <CoreFoundation/CoreFoundation.h>
#include <SystemConfiguration/SystemConfiguration.h>
#include <wsutil/cfutils.h>
/*
* On macOS, we get the "friendly name" and interface type for the interface
* from the System Configuration framework.
*
* To find the System Configuration framework information for the
* interface, we get all the interfaces that the System Configuration
* framework knows about and look for the one with a "BSD name" matching
* the interface name.
*
* If we find it, we use its "localized display name", if it has one, as
* the "friendly name".
*
* As for the interface type:
*
* Yes, fetching all the network addresses for an interface gets you an
* AF_LINK address, of type "struct sockaddr_dl", and, yes, that includes
* an SNMP MIB-II ifType value.
*
* However, it's IFT_ETHER, i.e. Ethernet, for AirPort interfaces,
* not IFT_IEEE80211 (which isn't defined in macOS in any case).
*
* Perhaps some other BSD-flavored OSes won't make this mistake;
* however, FreeBSD 7.0 and OpenBSD 4.2, at least, appear to have
* made the same mistake, at least for my Belkin ZyDAS stick.
*
* SCNetworkInterfaceGetInterfaceType() will get the interface
* type. The interface type is a CFString, and:
*
* kSCNetworkInterfaceTypeIEEE80211 means IF_WIRELESS;
* kSCNetworkInterfaceTypeBluetooth means IF_BLUETOOTH;
* kSCNetworkInterfaceTypeModem or
* kSCNetworkInterfaceTypePPP or
* maybe kSCNetworkInterfaceTypeWWAN means IF_DIALUP
*/
static void
add_unix_interface_ifinfo(if_info_t *if_info, const char *name,
const char *description _U_)
{
CFStringRef name_CFString;
CFArrayRef interfaces;
CFIndex num_interfaces;
CFIndex i;
SCNetworkInterfaceRef interface;
CFStringRef bsdname_CFString;
CFStringRef friendly_name_CFString;
CFStringRef interface_type_CFString;
interfaces = SCNetworkInterfaceCopyAll();
if (interfaces == NULL) {
/*
* Couldn't get a list of interfaces.
*/
return;
}
name_CFString = CFStringCreateWithCString(kCFAllocatorDefault,
name, kCFStringEncodingUTF8);
if (name_CFString == NULL) {
/*
* Couldn't convert the interface name to a CFString.
*/
CFRelease(interfaces);
return;
}
num_interfaces = CFArrayGetCount(interfaces);
for (i = 0; i < num_interfaces; i++) {
interface = (SCNetworkInterfaceRef)CFArrayGetValueAtIndex(interfaces, i);
bsdname_CFString = SCNetworkInterfaceGetBSDName(interface);
if (bsdname_CFString == NULL) {
/*
* This interface has no BSD name, so it's not
* a regular network interface.
*/
continue;
}
if (CFStringCompare(name_CFString, bsdname_CFString, 0) == 0) {
/*
* This is the interface.
* First, get the friendly name.
*/
friendly_name_CFString = SCNetworkInterfaceGetLocalizedDisplayName(interface);
if (friendly_name_CFString != NULL)
if_info->friendly_name = CFString_to_C_string(friendly_name_CFString);
/*
* Now get the interface type.
*/
interface_type_CFString = SCNetworkInterfaceGetInterfaceType(interface);
if (CFStringCompare(interface_type_CFString,
kSCNetworkInterfaceTypeIEEE80211, 0) == kCFCompareEqualTo)
if_info->type = IF_WIRELESS;
else if (CFStringCompare(interface_type_CFString,
kSCNetworkInterfaceTypeBluetooth, 0) == kCFCompareEqualTo)
if_info->type = IF_BLUETOOTH;
else if (CFStringCompare(interface_type_CFString,
kSCNetworkInterfaceTypeModem, 0) == kCFCompareEqualTo)
if_info->type = IF_DIALUP;
else if (CFStringCompare(interface_type_CFString,
kSCNetworkInterfaceTypePPP, 0) == kCFCompareEqualTo)
if_info->type = IF_DIALUP;
else if (CFStringCompare(interface_type_CFString,
kSCNetworkInterfaceTypeWWAN, 0) == kCFCompareEqualTo)
if_info->type = IF_DIALUP;
else
if_info->type = IF_WIRED;
break;
}
}
CFRelease(interfaces);
CFRelease(name_CFString);
}
#elif defined(__linux__)
/*
* Linux doesn't offer any form of "friendly name", but you can
* determine an interface type to some degree.
*/
static void
add_unix_interface_ifinfo(if_info_t *if_info, const char *name,
const char *description _U_)
{
char *wireless_path;
ws_statb64 statb;
/*
* Look for /sys/class/net/{device}/wireless. If it exists,
* it's a wireless interface.
*/
wireless_path = ws_strdup_printf("/sys/class/net/%s/wireless", name);
if (wireless_path != NULL) {
if (ws_stat64(wireless_path, &statb) == 0)
if_info->type = IF_WIRELESS;
g_free(wireless_path);
}
if (if_info->type == IF_WIRED) {
/*
* We still don't know what it is. Check for
* Bluetooth and USB devices.
*/
if (strstr(name, "bluetooth") != NULL) {
/*
* XXX - this is for raw Bluetooth capture; what
* about IP-over-Bluetooth devices?
*/
if_info->type = IF_BLUETOOTH;
} else if (strstr(name, "usbmon") != NULL)
if_info->type = IF_USB;
}
}
#elif !defined(_WIN32)
/*
* On other UN*Xes, if there is a description, it's a friendly
* name, and there is no vendor description. ("Other UN*Xes"
* currently means "FreeBSD and OpenBSD".)
*/
static void
add_unix_interface_ifinfo(if_info_t *if_info, const char *name _U_,
const char *description)
{
if_info->friendly_name = g_strdup(description);
}
#endif
if_info_t *
if_info_get(const char *name)
{
char *description = NULL;
if_info_t *if_info;
#ifdef SIOCGIFDESCR
/*
* Try to fetch the description of this interface.
* XXX - this is only here because libpcap has no API to
* get the description of a *single* interface; it really
* needs both an API to get pcapng-IDB-style attributes
* for a single interface and to get a list of interfaces
* with pcapng-IDB-style attributes for each interface.
*/
int s;
struct ifreq ifrdesc;
#ifndef IFDESCRSIZE
size_t descrlen = 64;
#else
size_t descrlen = IFDESCRSIZE;
#endif /* IFDESCRSIZE */
/*
* Get the description for the interface.
*/
memset(&ifrdesc, 0, sizeof ifrdesc);
(void) g_strlcpy(ifrdesc.ifr_name, name, sizeof ifrdesc.ifr_name);
s = socket(AF_INET, SOCK_DGRAM, 0);
if (s >= 0) {
#ifdef __FreeBSD__
/*
* On FreeBSD, if the buffer isn't big enough for the
* description, the ioctl succeeds, but the description
* isn't copied, ifr_buffer.length is set to the description
* length, and ifr_buffer.buffer is set to NULL.
*/
for (;;) {
g_free(description);
if ((description = (char*)g_malloc(descrlen)) != NULL) {
ifrdesc.ifr_buffer.buffer = description;
ifrdesc.ifr_buffer.length = descrlen;
if (ioctl(s, SIOCGIFDESCR, &ifrdesc) == 0) {
if (ifrdesc.ifr_buffer.buffer ==
description)
break;
else
descrlen = ifrdesc.ifr_buffer.length;
} else {
/*
* Failed to get interface description.
*/
g_free(description);
description = NULL;
break;
}
} else
break;
}
#else /* __FreeBSD__ */
/*
* The only other OS that currently supports
* SIOCGIFDESCR is OpenBSD, and it has no way
* to get the description length - it's clamped
* to a maximum of IFDESCRSIZE.
*/
if ((description = (char*)g_malloc(descrlen)) != NULL) {
ifrdesc.ifr_data = (caddr_t)description;
if (ioctl(s, SIOCGIFDESCR, &ifrdesc) != 0) {
/*
* Failed to get interface description.
*/
g_free(description);
description = NULL;
}
}
#endif /* __FreeBSD__ */
close(s);
if (description != NULL && strlen(description) == 0) {
/*
* Description is empty, so discard it.
*/
g_free(description);
description = NULL;
}
}
#ifdef __FreeBSD__
/*
* For FreeBSD, if we didn't get a description, and this is
* a device with a name of the form usbusN, label it as a USB
* bus.
*/
if (description == NULL) {
if (strncmp(name, "usbus", 5) == 0) {
/*
* OK, it begins with "usbus".
*/
long busnum;
char *p;
errno = 0;
busnum = strtol(name + 5, &p, 10);
if (errno == 0 && p != name + 5 && *p == '\0' &&
busnum >= 0 && busnum <= INT_MAX) {
/*
* OK, it's a valid number that's not
* bigger than INT_MAX. Construct
* a description from it.
*/
static const char descr_prefix[] = "USB bus number ";
size_t descr_size;
/*
* Allow enough room for a 32-bit bus number.
* sizeof (descr_prefix) includes the
* terminating NUL.
*/
descr_size = sizeof (descr_prefix) + 10;
description = g_malloc(descr_size);
if (description != NULL) {
snprintf(description, descr_size,
"%s%ld", descr_prefix, busnum);
}
}
}
}
#endif /* __FreeBSD__ */
#endif /* SIOCGIFDESCR */
if_info = if_info_new(name, description, false);
g_free(description);
return if_info;
}
if_addr_t *
if_addr_copy(const if_addr_t *addr)
{
if_addr_t *new_addr = g_new(if_addr_t, 1);
new_addr->ifat_type = addr->ifat_type;
switch (addr->ifat_type) {
case IF_AT_IPv4:
new_addr->addr.ip4_addr = addr->addr.ip4_addr;
break;
case IF_AT_IPv6:
memcpy(new_addr->addr.ip6_addr, addr->addr.ip6_addr, sizeof(addr->addr));
break;
default:
/* In case we add non-IP addresses */
break;
}
return new_addr;
}
static void*
if_addr_copy_cb(const void *data, void *user_data _U_)
{
return if_addr_copy((if_addr_t*)data);
}
void
if_info_free(if_info_t *if_info)
{
if (if_info == NULL) {
return;
}
g_free(if_info->name);
g_free(if_info->friendly_name);
g_free(if_info->vendor_description);
g_free(if_info->extcap);
g_slist_free_full(if_info->addrs, g_free);
if (if_info->caps) {
free_if_capabilities(if_info->caps);
}
g_free(if_info);
}
static void*
copy_linktype_cb(const void *data, void *user_data _U_)
{
data_link_info_t *linktype_info = (data_link_info_t *)data;
data_link_info_t *ret = g_new(data_link_info_t, 1);
ret->dlt = linktype_info->dlt;
ret->name = g_strdup(linktype_info->name);
ret->description = g_strdup(linktype_info->description);
return ret;
}
static void*
copy_timestamp_cb(const void *data, void *user_data _U_)
{
timestamp_info_t *timestamp_info = (timestamp_info_t *)data;
timestamp_info_t *ret = g_new(timestamp_info_t, 1);
ret->name = g_strdup(timestamp_info->name);
ret->description = g_strdup(timestamp_info->description);
return ret;
}
static if_capabilities_t *
if_capabilities_copy(const if_capabilities_t *caps)
{
if (caps == NULL) return NULL;
if_capabilities_t *ret = g_new(if_capabilities_t, 1);
ret->can_set_rfmon = caps->can_set_rfmon;
ret->data_link_types = g_list_copy_deep(caps->data_link_types, copy_linktype_cb, NULL);
ret->timestamp_types = g_list_copy_deep(caps->timestamp_types, copy_timestamp_cb, NULL);
ret->data_link_types_rfmon = g_list_copy_deep(caps->data_link_types_rfmon, copy_linktype_cb, NULL);
ret->primary_msg = g_strdup(caps->primary_msg);
ret->secondary_msg = caps->secondary_msg;
return ret;
}
if_info_t *
if_info_copy(const if_info_t *if_info)
{
if_info_t *new_if_info;
new_if_info = g_new(if_info_t, 1);
new_if_info->name = g_strdup(if_info->name);
/* g_strdup accepts NULL as input and returns NULL. */
new_if_info->friendly_name = g_strdup(if_info->friendly_name);
new_if_info->vendor_description = g_strdup(if_info->vendor_description);
new_if_info->addrs = g_slist_copy_deep(if_info->addrs, if_addr_copy_cb, NULL);
new_if_info->type = if_info->type;
new_if_info->loopback = if_info->loopback;
new_if_info->extcap = g_strdup(if_info->extcap);
new_if_info->caps = if_capabilities_copy(if_info->caps);
return new_if_info;
}
static void*
if_info_copy_cb(const void* data, void *user_data _U_)
{
return if_info_copy((const if_info_t*)data);
}
if_info_t *
if_info_new(const char *name, const char *description, bool loopback)
{
if_info_t *if_info;
#ifdef _WIN32
const char *guid_text;
GUID guid;
#endif
if_info = g_new(if_info_t, 1);
if_info->name = g_strdup(name);
if_info->friendly_name = NULL; /* default - unknown */
if_info->vendor_description = NULL;
if_info->type = IF_WIRED; /* default */
if_info->extcap = g_strdup("");
#ifdef _WIN32
/*
* Get the interface type.
*
* Much digging failed to reveal any obvious way to get something
* such as the SNMP MIB-II ifType value for an interface:
*
* https://www.iana.org/assignments/ianaiftype-mib/ianaiftype-mib
*
* by making some NDIS request. And even if there were such
* a way, there's no guarantee that the ifType reflects an
* interface type that a user would view as correct (for
* example, some systems report Wi-Fi interfaces as
* Ethernet interfaces).
*
* So we look for keywords in the vendor's interface
* description.
*/
if (description && (strstr(description, "generic dialup") != NULL ||
strstr(description, "PPP/SLIP") != NULL)) {
if_info->type = IF_DIALUP;
} else if (description && (strstr(description, "Wireless") != NULL ||
strstr(description,"802.11") != NULL)) {
if_info->type = IF_WIRELESS;
} else if (description && (strstr(description, "AirPcap") != NULL ||
strstr(name, "airpcap") != NULL)) {
if_info->type = IF_AIRPCAP;
} else if (description && strstr(description, "Bluetooth") != NULL ) {
if_info->type = IF_BLUETOOTH;
} else if (description && strstr(description, "VMware") != NULL) {
/*
* Bridge, NAT, or host-only interface on a VMware host.
*
* XXX - what about guest interfaces?
*/
if_info->type = IF_VIRTUAL;
}
/*
* On Windows, the "description" is a vendor description,
* and the friendly name isn't returned by Npcap.
* Fetch it ourselves.
*/
/*
* Skip over the "\Device\NPF_" prefix in the device name,
* if present.
*/
if (strncmp("\\Device\\NPF_", name, 12) == 0)
guid_text = name + 12;
else
guid_text = name;
/* Now try to parse what remains as a GUID. */
if (parse_as_guid(guid_text, &guid)) {
/*
* Success. Try to get a friendly name using the GUID.
* As this is a regular interface, the description is a
* vendor description.
*/
if_info->friendly_name = get_interface_friendly_name_from_device_guid(&guid);
if_info->vendor_description = g_strdup(description);
} else {
/*
* This is probably not a regular interface; we only
* support NT 5 (W2K) and later, so all regular interfaces
* should have GUIDs at the end of the name. Therefore,
* the description, if supplied, is a friendly name
* provided by Npcap, and there is no vendor
* description.
*/
if_info->friendly_name = g_strdup(description);
if_info->vendor_description = NULL;
}
#else
/*
* On UN*X, if there is a description, it's a friendly
* name, and there is no vendor description.
*
* Try the platform's way of getting a friendly name and
* interface type first.
*
* If that fails, then, for a loopback interface, give it the
* friendly name "Loopback" and, for VMware interfaces,
* give them the type IF_VIRTUAL.
*/
add_unix_interface_ifinfo(if_info, name, description);
if (if_info->type == IF_WIRED) {
/*
* This is the default interface type.
*
* Bridge, NAT, or host-only interfaces on VMWare hosts
* have the name vmnet[0-9]+. Guests might use a native
* (LANCE or E1000) driver or the vmxnet driver. Check
* the name.
*/
if (g_ascii_strncasecmp(name, "vmnet", 5) == 0)
if_info->type = IF_VIRTUAL;
else if (g_ascii_strncasecmp(name, "vmxnet", 6) == 0)
if_info->type = IF_VIRTUAL;
}
if (if_info->friendly_name == NULL) {
/*
* We couldn't get interface information using platform-
* dependent calls.
*
* If this is a loopback interface, give it a
* "friendly name" of "Loopback".
*/
if (loopback)
if_info->friendly_name = g_strdup("Loopback");
}
if_info->vendor_description = NULL;
#endif
if_info->loopback = loopback;
if_info->addrs = NULL;
if_info->caps = NULL;
return if_info;
}
void
if_info_add_address(if_info_t *if_info, struct sockaddr *addr)
{
if_addr_t *if_addr;
struct sockaddr_in *ai;
struct sockaddr_in6 *ai6;
switch (addr->sa_family) {
case AF_INET:
ai = (struct sockaddr_in *)(void *)addr;
if_addr = (if_addr_t *)g_malloc(sizeof(*if_addr));
if_addr->ifat_type = IF_AT_IPv4;
if_addr->addr.ip4_addr = ai->sin_addr.s_addr;
if_info->addrs = g_slist_prepend(if_info->addrs, if_addr);
break;
case AF_INET6:
ai6 = (struct sockaddr_in6 *)(void *)addr;
if_addr = (if_addr_t *)g_malloc(sizeof(*if_addr));
if_addr->ifat_type = IF_AT_IPv6;
memcpy((void *)&if_addr->addr.ip6_addr,
(void *)&ai6->sin6_addr.s6_addr,
sizeof if_addr->addr.ip6_addr);
if_info->addrs = g_slist_prepend(if_info->addrs, if_addr);
break;
}
}
/*
* Get all IP address information for the given interface.
*/
static void
if_info_ip(if_info_t *if_info, pcap_if_t *d)
{
pcap_addr_t *a;
/* All addresses */
for (a = d->addresses; a != NULL; a = a->next) {
if (a->addr != NULL)
if_info_add_address(if_info, a->addr);
}
if(if_info->addrs){
if_info->addrs = g_slist_reverse(if_info->addrs);
}
}
#ifdef HAVE_PCAP_REMOTE
GList *
get_interface_list_findalldevs_ex(const char *hostname, const char *port,
int auth_type, const char *username,
const char *passwd, int *err, char **err_str)
{
char source[PCAP_BUF_SIZE];
struct pcap_rmtauth auth;
GList *il = NULL;
pcap_if_t *alldevs, *dev;
if_info_t *if_info;
/*
* WinPcap can overflow PCAP_ERRBUF_SIZE if the host is unreachable.
* Fudge a larger size.
*/
char errbuf[PCAP_ERRBUF_SIZE*4];
if (pcap_createsrcstr(source, PCAP_SRC_IFREMOTE, hostname, port,
NULL, errbuf) == -1) {
*err = CANT_GET_INTERFACE_LIST;
if (strcmp(errbuf, "not supported") == 0) {
/*
* macOS 14's pcap_createsrcstr(), which is a
* stub that always returns -1 with an error
* message of "not supported".
*
* In this case, as we passed it an rpcap://
* URL, treat that as meaning "remote capture
* not supported".
*/
g_strlcpy(errbuf, "Remote capture not supported",
PCAP_ERRBUF_SIZE);
}
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);
if (ws_pcap_findalldevs_ex(source, &auth, &alldevs, errbuf) == -1) {
*err = CANT_GET_INTERFACE_LIST;
if (strcmp(errbuf, "not supported") == 0) {
/*
* macOS 14's pcap_findalldevs_ex(), which is a
* stub that always returns -1 with an error
* message of "not supported".
*
* In this case, as we passed it an rpcap://
* URL, treat that as meaning "remote capture
* not supported".
*/
g_strlcpy(errbuf, "Remote capture not supported",
PCAP_ERRBUF_SIZE);
}
if (err_str != NULL)
*err_str = cant_get_if_list_error_message(errbuf);
g_free(auth.username);
g_free(auth.password);
return NULL;
}
if (alldevs == NULL) {
/*
* No interfaces found.
*/
*err = 0;
if (err_str != NULL)
*err_str = NULL;
g_free(auth.username);
g_free(auth.password);
return NULL;
}
for (dev = alldevs; dev != NULL; dev = dev->next) {
if_info = if_info_new(dev->name, dev->description,
(dev->flags & PCAP_IF_LOOPBACK) ? true : false);
il = g_list_append(il, if_info);
if_info_ip(if_info, dev);
}
pcap_freealldevs(alldevs);
g_free(auth.username);
g_free(auth.password);
return il;
}
#endif
GList *
get_interface_list_findalldevs(int *err, char **err_str)
{
GList *il = NULL;
pcap_if_t *alldevs = NULL, *dev;
if_info_t *if_info;
char errbuf[PCAP_ERRBUF_SIZE];
if (application_flavor_is_wireshark() && pcap_findalldevs(&alldevs, errbuf) == -1) {
*err = CANT_GET_INTERFACE_LIST;
if (err_str != NULL)
*err_str = cant_get_if_list_error_message(errbuf);
return NULL;
}
if (alldevs == NULL) {
/*
* No interfaces found.
*/
*err = 0;
if (err_str != NULL)
*err_str = NULL;
return NULL;
}
for (dev = alldevs; dev != NULL; dev = dev->next) {
if_info = if_info_new(dev->name, dev->description,
(dev->flags & PCAP_IF_LOOPBACK) ? true : false);
il = g_list_append(il, if_info);
if_info_ip(if_info, dev);
}
pcap_freealldevs(alldevs);
return il;
}
static void
free_if_cb(void * data, void * user_data _U_)
{
if_info_free((if_info_t *)data);
}
void
free_interface_list(GList *if_list)
{
g_list_foreach(if_list, free_if_cb, NULL);
g_list_free(if_list);
}
GList*
interface_list_copy(GList *if_list)
{
return g_list_copy_deep(if_list, if_info_copy_cb, NULL);
}
static void
free_linktype_cb(void * data)
{
data_link_info_t *linktype_info = (data_link_info_t *)data;
g_free(linktype_info->name);
g_free(linktype_info->description);
g_free(linktype_info);
}
static void
free_timestamp_cb(void * data)
{
timestamp_info_t *timestamp_info = (timestamp_info_t *)data;
g_free(timestamp_info->name);
g_free(timestamp_info->description);
g_free(data);
}
void
free_if_capabilities(if_capabilities_t *caps)
{
g_list_free_full(caps->data_link_types, free_linktype_cb);
g_list_free_full(caps->data_link_types_rfmon, free_linktype_cb);
g_list_free_full(caps->timestamp_types, free_timestamp_cb);
g_free(caps->primary_msg);
g_free(caps);
}
const char *
linktype_val_to_name(int dlt)
{
return pcap_datalink_val_to_name(dlt);
}
int
linktype_name_to_val(const char *linktype)
{
return pcap_datalink_name_to_val(linktype);
}
/*
* Get the data-link type for a libpcap device.
* This works around AIX 5.x's non-standard and incompatible-with-the-
* rest-of-the-universe libpcap.
*/
int
get_pcap_datalink(pcap_t *pch,
#ifdef _AIX
const char* devicename
#else
const char* devicename _U_
#endif
)
{
int datalink;
#ifdef _AIX
const char *ifacename;
#endif
datalink = pcap_datalink(pch);
#ifdef _AIX
/*
* The libpcap that comes with AIX 5.x uses RFC 1573 ifType values
* rather than DLT_ values for link-layer types; the ifType values
* for LAN devices are:
*
* Ethernet 6
* 802.3 7
* Token Ring 9
* FDDI 15
*
* and the ifType value for a loopback device is 24.
*
* The AIX names for LAN devices begin with:
*
* Ethernet en
* 802.3 et
* Token Ring tr
* FDDI fi
*
* and the AIX names for loopback devices begin with "lo".
*
* (The difference between "Ethernet" and "802.3" is presumably
* whether packets have an Ethernet header, with a packet type,
* or an 802.3 header, with a packet length, followed by an 802.2
* header and possibly a SNAP header.)
*
* If the device name matches "datalink" interpreted as an ifType
* value, rather than as a DLT_ value, we will assume this is AIX's
* non-standard, incompatible libpcap, rather than a standard libpcap,
* and will map the link-layer type to the standard DLT_ value for
* that link-layer type, as that's what the rest of Wireshark expects.
*
* (This means the capture files won't be readable by a tcpdump
* linked with AIX's non-standard libpcap, but so it goes. They
* *will* be readable by standard versions of tcpdump, Wireshark,
* and so on.)
*
* XXX - if we conclude we're using AIX libpcap, should we also
* set a flag to cause us to assume the time stamps are in
* seconds-and-nanoseconds form, and to convert them to
* seconds-and-microseconds form before processing them and
* writing them out?
*/
/*
* Find the last component of the device name, which is the
* interface name.
*/
ifacename = strchr(devicename, '/');
if (ifacename == NULL)
ifacename = devicename;
/* See if it matches any of the LAN device names. */
if (strncmp(ifacename, "en", 2) == 0) {
if (datalink == 6) {
/*
* That's the RFC 1573 value for Ethernet;
* map it to DLT_EN10MB.
*/
datalink = 1;
}
} else if (strncmp(ifacename, "et", 2) == 0) {
if (datalink == 7) {
/*
* That's the RFC 1573 value for 802.3;
* map it to DLT_EN10MB.
*
* (libpcap, tcpdump, Wireshark, etc. don't
* care if it's Ethernet or 802.3.)
*/
datalink = 1;
}
} else if (strncmp(ifacename, "tr", 2) == 0) {
if (datalink == 9) {
/*
* That's the RFC 1573 value for 802.5 (Token Ring);
* map it to DLT_IEEE802, which is what's used for
* Token Ring.
*/
datalink = 6;
}
} else if (strncmp(ifacename, "fi", 2) == 0) {
if (datalink == 15) {
/*
* That's the RFC 1573 value for FDDI;
* map it to DLT_FDDI.
*/
datalink = 10;
}
} else if (strncmp(ifacename, "lo", 2) == 0) {
if (datalink == 24) {
/*
* That's the RFC 1573 value for "software loopback"
* devices; map it to DLT_NULL, which is what's used
* for loopback devices on BSD.
*/
datalink = 0;
}
}
#endif
return datalink;
}
/* Set the data link type on a pcap. */
bool
set_pcap_datalink(pcap_t *pcap_h, int datalink, char *name,
char *errmsg, size_t errmsg_len,
char *secondary_errmsg, size_t secondary_errmsg_len)
{
char *set_datalink_err_str;
if (datalink == -1)
return true; /* just use the default */
if (pcap_set_datalink(pcap_h, datalink) == 0)
return true; /* no error */
set_datalink_err_str = pcap_geterr(pcap_h);
snprintf(errmsg, errmsg_len, "Unable to set data link type on interface '%s' (%s).",
name, set_datalink_err_str);
/*
* If the error isn't "XXX is not one of the DLTs supported by this device",
* tell the user to tell the Wireshark developers about it.
*/
if (strstr(set_datalink_err_str, "is not one of the DLTs supported by this device") == NULL)
snprintf(secondary_errmsg, secondary_errmsg_len,
"%s", please_report_bug());
else
secondary_errmsg[0] = '\0';
return false;
}
static data_link_info_t *
create_data_link_info(int dlt)
{
data_link_info_t *data_link_info;
const char *text;
data_link_info = g_new(data_link_info_t, 1);
data_link_info->dlt = dlt;
text = pcap_datalink_val_to_name(dlt);
if (text != NULL)
data_link_info->name = g_strdup(text);
else
data_link_info->name = ws_strdup_printf("DLT %d", dlt);
text = pcap_datalink_val_to_description(dlt);
data_link_info->description = g_strdup(text);
return data_link_info;
}
static GList *
get_data_link_types(pcap_t *pch, interface_options *interface_opts,
cap_device_open_status *status, char **status_str)
{
GList *data_link_types;
int deflt;
int *linktypes;
int i, nlt;
data_link_info_t *data_link_info;
deflt = get_pcap_datalink(pch, interface_opts->name);
nlt = pcap_list_datalinks(pch, &linktypes);
if (nlt < 0) {
/*
* A negative return is an error.
*/
/*
* If we have pcap_create(), we have
* pcap_statustostr(), and we can get back errors
* other than PCAP_ERROR (-1), such as
* PCAP_ERROR_NOT_ACTIVATED. and we should report
* them properly.
*/
switch (nlt) {
case PCAP_ERROR:
*status = CAP_DEVICE_OPEN_ERROR_OTHER;
*status_str = ws_strdup_printf("pcap_list_datalinks() failed: %s",
pcap_geterr(pch));
break;
default:
/*
* This "shouldn't happen".
*/
*status = CAP_DEVICE_OPEN_ERROR_OTHER;
*status_str = ws_strdup_printf("pcap_list_datalinks() failed: %s - %s",
pcap_statustostr(nlt), pcap_geterr(pch));
break;
}
return NULL;
}
data_link_types = NULL;
for (i = 0; i < nlt; i++) {
data_link_info = create_data_link_info(linktypes[i]);
/*
* XXX - for 802.11, make the most detailed 802.11
* version the default, rather than the one the
* device has as the default?
*/
if (linktypes[i] == deflt)
data_link_types = g_list_prepend(data_link_types,
data_link_info);
else
data_link_types = g_list_append(data_link_types,
data_link_info);
}
pcap_free_datalinks(linktypes);
*status_str = NULL;
return data_link_types;
}
/* Get supported timestamp types for a libpcap device. */
static GList*
get_pcap_timestamp_types(pcap_t *pch _U_, char **err_str _U_)
{
GList *list = NULL;
int *types;
int ntypes = pcap_list_tstamp_types(pch, &types);
if (err_str)
*err_str = ntypes < 0 ? pcap_geterr(pch) : NULL;
if (ntypes <= 0)
return NULL;
while (ntypes--) {
timestamp_info_t *info = (timestamp_info_t *)g_malloc(sizeof *info);
info->name = g_strdup(pcap_tstamp_type_val_to_name(types[ntypes]));
info->description = g_strdup(pcap_tstamp_type_val_to_description(types[ntypes]));
list = g_list_prepend(list, info);
}
pcap_free_tstamp_types(types);
return list;
}
/*
* Request high-resolution time stamps.
*
* If this fails with PCAP_ERROR_TSTAMP_PRECISION_NOTSUP, that means
* that boring old microsecond-resolution time stamps are all that
* are supported, so we just live with that.
*/
static int
request_high_resolution_timestamp(pcap_t *pcap_h)
{
int status;
#ifdef __APPLE__
/*
* On macOS, 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 macOS "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.
*
* XXX - This shouldn't be needed anymore; we don't support running
* on any release older than macOS 11, and starting with macOS 11 the
* system libpcap is based on libpcap 1.5 or later and has
* pcap_set_tstamp_precision().
*/
static bool 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) {
status = (*p_pcap_set_tstamp_precision)(pcap_h,
PCAP_TSTAMP_PRECISION_NANO);
} else {
/*
* Older libpcap, which doesn't have support
* for setting the time stamp resolution.
*/
status = PCAP_ERROR_TSTAMP_PRECISION_NOTSUP;
}
#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.
*/
status = pcap_set_tstamp_precision(pcap_h, PCAP_TSTAMP_PRECISION_NANO);
#endif /* __APPLE__ */
if (status == PCAP_ERROR_TSTAMP_PRECISION_NOTSUP) {
/* This isn't a fatal error. */
status = 0;
}
return status;
}
/*
* Return true if the pcap_t in question is set up for high-precision
* time stamps, false otherwise.
*/
bool
have_high_resolution_timestamp(pcap_t *pcap_h)
{
#ifdef __APPLE__
/*
* See above.
*/
static bool 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__ */
}
#ifdef HAVE_BONDING
static bool
is_linux_bonding_device(const char *ifname)
{
int fd;
struct ifreq ifr;
ifbond ifb;
fd = socket(PF_INET, SOCK_DGRAM, 0);
if (fd == -1)
return false;
memset(&ifr, 0, sizeof ifr);
(void) g_strlcpy(ifr.ifr_name, ifname, sizeof ifr.ifr_name);
memset(&ifb, 0, sizeof ifb);
ifr.ifr_data = (caddr_t)&ifb;
#if defined(SIOCBONDINFOQUERY)
if (ioctl(fd, SIOCBONDINFOQUERY, &ifr) == 0) {
close(fd);
return true;
}
#else
if (ioctl(fd, BOND_INFO_QUERY_OLD, &ifr) == 0) {
close(fd);
return true;
}
#endif
close(fd);
return false;
}
#else
static bool
is_linux_bonding_device(const char *ifname _U_)
{
return false;
}
#endif
if_capabilities_t *
get_if_capabilities_pcap_create(interface_options *interface_opts,
cap_device_open_status *open_status, char **open_status_str)
{
if_capabilities_t *caps;
char errbuf[PCAP_ERRBUF_SIZE];
pcap_t *pch;
int status;
pch = pcap_create(interface_opts->name, errbuf);
if (pch == NULL) {
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
*open_status_str = g_strdup(errbuf);
return NULL;
}
if (is_linux_bonding_device(interface_opts->name)) {
/*
* Linux bonding device; not Wi-Fi, so no monitor mode, and
* calling pcap_can_set_rfmon() might get a "no such device"
* error.
*/
status = 0;
} else {
/*
* Not a Linux bonding device, so go ahead.
*/
status = pcap_can_set_rfmon(pch);
}
if (status < 0) {
/* Error. */
switch (status) {
case PCAP_ERROR_NO_SUCH_DEVICE:
*open_status = CAP_DEVICE_OPEN_ERROR_NO_SUCH_DEVICE;
*open_status_str = ws_strdup_printf("pcap_can_set_rfmon() failed: %s",
pcap_geterr(pch));
break;
case PCAP_ERROR_PERM_DENIED:
*open_status = CAP_DEVICE_OPEN_ERROR_PERM_DENIED;
*open_status_str = ws_strdup_printf("pcap_can_set_rfmon() failed: %s",
pcap_geterr(pch));
break;
case PCAP_ERROR:
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
*open_status_str = ws_strdup_printf("pcap_can_set_rfmon() failed: %s",
pcap_geterr(pch));
break;
default:
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
*open_status_str = ws_strdup_printf("pcap_can_set_rfmon() failed: %s - %s",
pcap_statustostr(status), pcap_geterr(pch));
break;
}
pcap_close(pch);
return NULL;
}
caps = (if_capabilities_t *)g_malloc0(sizeof *caps);
if (status == 0)
caps->can_set_rfmon = false;
else if (status == 1) {
caps->can_set_rfmon = true;
if (interface_opts->monitor_mode) {
status = pcap_set_rfmon(pch, 1);
if (status < 0) {
/*
* This "should not happen".
*/
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
*open_status_str = ws_strdup_printf("pcap_set_rfmon() returned %d",
status);
pcap_close(pch);
g_free(caps);
return NULL;
}
}
} else {
/*
* This "should not happen".
*/
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
*open_status_str = ws_strdup_printf("pcap_can_set_rfmon() returned %d",
status);
pcap_close(pch);
g_free(caps);
return NULL;
}
status = pcap_activate(pch);
if (status < 0) {
/* Error. */
switch (status) {
case PCAP_ERROR_NO_SUCH_DEVICE:
*open_status = CAP_DEVICE_OPEN_ERROR_NO_SUCH_DEVICE;
*open_status_str = ws_strdup_printf("pcap_activate() failed: %s",
pcap_geterr(pch));
break;
case PCAP_ERROR_PERM_DENIED:
*open_status = CAP_DEVICE_OPEN_ERROR_PERM_DENIED;
*open_status_str = ws_strdup_printf("pcap_activate() failed: %s",
pcap_geterr(pch));
break;
case PCAP_ERROR_IFACE_NOT_UP:
*open_status = CAP_DEVICE_OPEN_ERROR_IFACE_NOT_UP;
*open_status_str = ws_strdup_printf("pcap_activate() failed: %s",
pcap_geterr(pch));
break;
case PCAP_ERROR:
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
*open_status_str = ws_strdup_printf("pcap_activate() failed: %s",
pcap_geterr(pch));
break;
default:
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
*open_status_str = ws_strdup_printf("pcap_activate() failed: %s - %s",
pcap_statustostr(status), pcap_geterr(pch));
break;
}
pcap_close(pch);
g_free(caps);
return NULL;
}
caps->data_link_types = get_data_link_types(pch, interface_opts,
open_status, open_status_str);
if (caps->data_link_types == NULL) {
pcap_close(pch);
g_free(caps);
return NULL;
}
if (interface_opts->monitor_mode) {
caps->data_link_types_rfmon = caps->data_link_types;
caps->data_link_types = NULL;
}
caps->timestamp_types = get_pcap_timestamp_types(pch, NULL);
pcap_close(pch);
*open_status = CAP_DEVICE_OPEN_NO_ERR;
if (open_status_str != NULL)
*open_status_str = NULL;
return caps;
}
static void
set_open_status_str(int status, pcap_t *pcap_h,
char (*open_status_str)[PCAP_ERRBUF_SIZE])
{
switch (status) {
case PCAP_ERROR:
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
default:
(void) g_strlcpy(*open_status_str, pcap_statustostr(status),
sizeof *open_status_str);
break;
}
}
pcap_t *
open_capture_device_pcap_create(
capture_options* capture_opts _U_,
interface_options *interface_opts, int timeout,
cap_device_open_status *open_status,
char (*open_status_str)[PCAP_ERRBUF_SIZE])
{
pcap_t *pcap_h;
int status;
ws_debug("Calling pcap_create() using %s.", interface_opts->name);
pcap_h = pcap_create(interface_opts->name, *open_status_str);
ws_debug("pcap_create() returned %p.", (void *)pcap_h);
if (pcap_h == NULL) {
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
return NULL;
}
if (interface_opts->has_snaplen) {
ws_debug("Calling pcap_set_snaplen() with snaplen %d.",
interface_opts->snaplen);
status = pcap_set_snaplen(pcap_h, interface_opts->snaplen);
if (status < 0) {
/* Error. */
set_open_status_str(status, pcap_h, open_status_str);
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
pcap_close(pcap_h);
return NULL;
}
}
ws_debug("Calling pcap_set_promisc() with promisc_mode %d.",
interface_opts->promisc_mode);
status = pcap_set_promisc(pcap_h, interface_opts->promisc_mode);
if (status < 0) {
/* Error. */
set_open_status_str(status, pcap_h, open_status_str);
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
pcap_close(pcap_h);
return NULL;
}
status = pcap_set_timeout(pcap_h, timeout);
if (status < 0) {
/* Error. */
set_open_status_str(status, pcap_h, open_status_str);
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
pcap_close(pcap_h);
return NULL;
}
/*
* Try to enable nanosecond-resolution capture; any code
* that can read pcapng files must be able to handle
* nanosecond-resolution time stamps. We think at this
* point that code that reads pcap files should recognize
* the nanosecond-resolution pcap file magic number. If
* it doesn't, we can downconvert via a program that
* uses libwiretap.
*
* We don't care whether this succeeds or fails; if it
* fails (because we don't have pcap_set_tstamp_precision(),
* or because we do but the OS or device doesn't support
* nanosecond resolution timing), we just use the microsecond-
* resolution time stamps we get.
*/
status = request_high_resolution_timestamp(pcap_h);
if (status < 0) {
/* Error. */
set_open_status_str(status, pcap_h, open_status_str);
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
pcap_close(pcap_h);
return NULL;
}
if (interface_opts->timestamp_type) {
status = pcap_set_tstamp_type(pcap_h, interface_opts->timestamp_type_id);
/*
* XXX - what if it fails because that time stamp type
* isn't supported?
*/
if (status < 0) {
set_open_status_str(status, pcap_h, open_status_str);
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
pcap_close(pcap_h);
return NULL;
}
}
ws_debug("buffersize %d.", interface_opts->buffer_size);
if (interface_opts->buffer_size != 0) {
status = pcap_set_buffer_size(pcap_h,
interface_opts->buffer_size * 1024 * 1024);
if (status < 0) {
set_open_status_str(status, pcap_h, open_status_str);
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
pcap_close(pcap_h);
return NULL;
}
}
ws_debug("monitor_mode %d.", interface_opts->monitor_mode);
if (interface_opts->monitor_mode) {
status = pcap_set_rfmon(pcap_h, 1);
if (status < 0) {
set_open_status_str(status, pcap_h, open_status_str);
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
pcap_close(pcap_h);
return NULL;
}
}
status = pcap_activate(pcap_h);
ws_debug("pcap_activate() returned %d.", status);
if (status < 0) {
/* Failed to activate, set to NULL */
switch (status) {
case PCAP_ERROR_NO_SUCH_DEVICE:
*open_status = CAP_DEVICE_OPEN_ERROR_NO_SUCH_DEVICE;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
case PCAP_ERROR_PERM_DENIED:
*open_status = CAP_DEVICE_OPEN_ERROR_PERM_DENIED;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
case PCAP_ERROR_PROMISC_PERM_DENIED:
*open_status = CAP_DEVICE_OPEN_ERROR_PROMISC_PERM_DENIED;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
case PCAP_ERROR_RFMON_NOTSUP:
*open_status = CAP_DEVICE_OPEN_ERROR_RFMON_NOTSUP;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
case PCAP_ERROR_IFACE_NOT_UP:
*open_status = CAP_DEVICE_OPEN_ERROR_IFACE_NOT_UP;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
case PCAP_ERROR:
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
default:
*open_status = CAP_DEVICE_OPEN_ERROR_OTHER;
snprintf(*open_status_str, sizeof *open_status_str,
"%s - %s", pcap_statustostr(status), pcap_geterr(pcap_h));
break;
}
pcap_close(pcap_h);
return NULL;
}
if (status > 0) {
/*
* Warning. The call succeeded, but something happened
* that the user might want to know.
*/
switch (status) {
case PCAP_WARNING_PROMISC_NOTSUP:
*open_status = CAP_DEVICE_OPEN_WARNING_PROMISC_NOTSUP;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
case PCAP_WARNING_TSTAMP_TYPE_NOTSUP:
*open_status = CAP_DEVICE_OPEN_WARNING_TSTAMP_TYPE_NOTSUP;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
case PCAP_WARNING:
*open_status = CAP_DEVICE_OPEN_WARNING_OTHER;
(void) g_strlcpy(*open_status_str, pcap_geterr(pcap_h),
sizeof *open_status_str);
break;
default:
*open_status = CAP_DEVICE_OPEN_WARNING_OTHER;
snprintf(*open_status_str, sizeof *open_status_str,
"%s - %s", pcap_statustostr(status), pcap_geterr(pcap_h));
break;
}
} else {
/*
* No warning issued.
*/
*open_status = CAP_DEVICE_OPEN_NO_ERR;
}
return pcap_h;
}
/*
* Get the capabilities of a network device.
*/
if_capabilities_t *
get_if_capabilities(interface_options *interface_opts,
cap_device_open_status *status, char **status_str)
{
#if defined(HAVE_PCAP_OPEN) && defined(HAVE_PCAP_REMOTE)
if_capabilities_t *caps;
char errbuf[PCAP_ERRBUF_SIZE];
pcap_t *pch;
int deflt;
data_link_info_t *data_link_info;
if (strncmp (interface_opts->name, "rpcap://", 8) == 0) {
struct pcap_rmtauth auth;
auth.type = interface_opts->auth_type == CAPTURE_AUTH_PWD ?
RPCAP_RMTAUTH_PWD : RPCAP_RMTAUTH_NULL;
auth.username = interface_opts->auth_username;
auth.password = interface_opts->auth_password;
/*
* WinPcap 4.1.2, and possibly earlier versions, have a bug
* wherein, when an open with an rpcap: URL fails, the error
* message for the error is not copied to errbuf and whatever
* on-the-stack junk is in errbuf is treated as the error
* message.
*
* To work around that (and any other bugs of that sort), we
* initialize errbuf to an empty string. If we get an error
* and the string is empty, we report it as an unknown error.
* (If we *don't* get an error, and the string is *non*-empty,
* that could be a warning returned, such as "can't turn
* promiscuous mode on"; we currently don't do so.)
*/
errbuf[0] = '\0';
pch = pcap_open(interface_opts->name, MIN_PACKET_SIZE, 0, 0, &auth,
errbuf);
if (pch == NULL) {
/*
* We don't know whether it's a permission error or not.
* And, if it is, the user will either have to ask for
* permission for their own remote account or will have
* to use an account that *does* have permissions.
*/
*status = CAP_DEVICE_OPEN_ERROR_GENERIC;
if (strcmp(errbuf, "not supported") == 0) {
/*
* macOS 14's pcap_open(), which is a stub that
* always returns NULL with an error message of
* "not supported".
*
* In this case, as we passed it an rpcap://
* URL, treat that as meaning "remote capture
* not supported".
*/
g_strlcpy(errbuf, "Remote capture not supported",
PCAP_ERRBUF_SIZE);
}
*status_str = g_strdup(errbuf[0] == '\0' ? "Unknown error (pcap bug; actual error cause not reported)" : errbuf);
return NULL;
}
caps = (if_capabilities_t *)g_malloc0(sizeof *caps);
caps->can_set_rfmon = false;
caps->data_link_types = NULL;
deflt = get_pcap_datalink(pch, interface_opts->name);
data_link_info = create_data_link_info(deflt);
caps->data_link_types = g_list_append(caps->data_link_types, data_link_info);
caps->timestamp_types = get_pcap_timestamp_types(pch, NULL);
pcap_close(pch);
/*
* This doesn't return warnings for remote devices, and
* we don't use it for local devices.
*/
*status = CAP_DEVICE_OPEN_NO_ERR;
*status_str = NULL;
return caps;
}
#endif /* defined(HAVE_PCAP_OPEN) && defined(HAVE_PCAP_REMOTE) */
/*
* Local interface.
*/
return get_if_capabilities_local(interface_opts, status, status_str);
}
pcap_t *
open_capture_device(capture_options *capture_opts,
interface_options *interface_opts, int timeout,
cap_device_open_status *open_status,
char (*open_status_str)[PCAP_ERRBUF_SIZE])
{
pcap_t *pcap_h;
#if defined(HAVE_PCAP_OPEN) && defined(HAVE_PCAP_REMOTE)
struct pcap_rmtauth auth;
#endif
/* Open the network interface to capture from it.
Some versions of libpcap may put warnings into the error buffer
if they succeed; to tell if that's happened, we have to clear
the error buffer, and check if it's still a null string. */
ws_debug("Entering open_capture_device().");
*open_status = CAP_DEVICE_OPEN_NO_ERR;
(*open_status_str)[0] = '\0';
#if defined(HAVE_PCAP_OPEN) && defined(HAVE_PCAP_REMOTE)
/*
* If we're opening a remote device, use pcap_open(); that's currently
* the only open routine that supports remote devices.
*/
if (strncmp (interface_opts->name, "rpcap://", 8) == 0) {
int snaplen;
auth.type = interface_opts->auth_type == CAPTURE_AUTH_PWD ?
RPCAP_RMTAUTH_PWD : RPCAP_RMTAUTH_NULL;
auth.username = interface_opts->auth_username;
auth.password = interface_opts->auth_password;
if (interface_opts->has_snaplen)
snaplen = interface_opts->snaplen;
else {
/*
* Default - use the non-D-Bus maximum snapshot length,
* which should be big enough, except for D-Bus.
*/
snaplen = 256*1024;
}
ws_debug("Calling pcap_open() using name %s, snaplen %d, promisc_mode %d, datatx_udp %d, nocap_rpcap %d.",
interface_opts->name, snaplen,
interface_opts->promisc_mode, interface_opts->datatx_udp,
interface_opts->nocap_rpcap);
pcap_h = pcap_open(interface_opts->name, snaplen,
/* flags */
(interface_opts->promisc_mode ? PCAP_OPENFLAG_PROMISCUOUS : 0) |
(interface_opts->datatx_udp ? PCAP_OPENFLAG_DATATX_UDP : 0) |
(interface_opts->nocap_rpcap ? PCAP_OPENFLAG_NOCAPTURE_RPCAP : 0),
timeout, &auth, *open_status_str);
if (pcap_h == NULL) {
/*
* Error.
*
* We don't know whether it's a permission error
* or not.
* (If it is, maybe we can give ourselves permission
* or maybe we just have to ask politely for
* permission.)
*/
*open_status = CAP_DEVICE_OPEN_ERROR_GENERIC;
if (strcmp(*open_status_str, "not supported") == 0) {
/*
* macOS 14's pcap_open(), which is a stub
* that always returns NULL with an error
* message of "not supported".
*
* In this case, as we passed it an rpcap://
* URL, treat that as meaning "remote capture
* not supported".
*/
g_strlcpy(*open_status_str,
"Remote capture not supported",
PCAP_ERRBUF_SIZE);
}
/* Did pcap actually supply an error message? */
if ((*open_status_str)[0] == '\0') {
/*
* Work around known WinPcap bug wherein
* no error message is filled in on a
* failure to open an rpcap: URL.
*/
(void) g_strlcpy(*open_status_str,
"Unknown error (pcap bug; actual error cause not reported)",
sizeof *open_status_str);
}
}
ws_debug("pcap_open() returned %p.", (void *)pcap_h);
ws_debug("open_capture_device %s : %s", pcap_h ? "SUCCESS" : "FAILURE", interface_opts->name);
/*
* This doesn't return warnings for remote devices, and
* we don't use it for local devices.
*/
*open_status = CAP_DEVICE_OPEN_NO_ERR;
return pcap_h;
}
#endif
pcap_h = open_capture_device_local(capture_opts, interface_opts,
timeout, open_status, open_status_str);
ws_debug("open_capture_device %s : %s", pcap_h ? "SUCCESS" : "FAILURE", interface_opts->name);
return pcap_h;
}
/*
* Platform-dependent suggestions for fixing permissions.
*/
#ifdef HAVE_LIBCAP
#define LIBCAP_PERMISSIONS_SUGGESTION \
"\n\n" \
"If you did not install Wireshark from a package, ensure that Dumpcap " \
"has the needed CAP_NET_RAW and CAP_NET_ADMIN capabilities by running " \
"\n\n" \
" sudo setcap cap_net_raw,cap_net_admin=ep {path/to/}dumpcap" \
"\n\n" \
"and then restarting Wireshark."
#else
#define LIBCAP_PERMISSIONS_SUGGESTION
#endif
#if defined(__linux__)
#define PLATFORM_PERMISSIONS_SUGGESTION \
"\n\n" \
"On Debian and Debian derivatives such as Ubuntu, if you have " \
"installed Wireshark from a package, try running" \
"\n\n" \
" sudo dpkg-reconfigure wireshark-common" \
"\n\n" \
"selecting \"<Yes>\" in response to the question" \
"\n\n" \
" Should non-superusers be able to capture packets?" \
"\n\n" \
"adding yourself to the \"wireshark\" group by running" \
"\n\n" \
" sudo usermod -a -G wireshark {your username}" \
"\n\n" \
"and then logging out and logging back in again." \
LIBCAP_PERMISSIONS_SUGGESTION
#elif defined(__APPLE__)
#define PLATFORM_PERMISSIONS_SUGGESTION \
"\n\n" \
"If you installed Wireshark using the package from wireshark.org, " \
"close this dialog and click on the \"installing ChmodBPF\" link in " \
"\"You can fix this by installing ChmodBPF.\" on the main screen, " \
"and then complete the installation procedure."
#else
#define PLATFORM_PERMISSIONS_SUGGESTION
#endif
#if defined(_WIN32)
static const char *
get_platform_pcap_failure_secondary_error_message(const char *open_status_str)
{
/*
* The error string begins with the error produced by WinPcap
* and Npcap if attempting to set promiscuous mode fails.
* (Note that this string could have a specific error message
* from an NDIS error after the initial part, so we do a prefix
* check rather than an exact match check.)
*
* If this is with Npcap 1.71 through 1.73, which have bugs that
* cause this error on Windows 11 with some drivers, suggest that
* the user upgrade to the current version of Npcap;
* otherwise, suggest that they turn off promiscuous mode
* on that device.
*/
static const char promisc_failed[] =
"failed to set hardware filter to promiscuous mode";
if (strncmp(open_status_str, promisc_failed, sizeof promisc_failed - 1) == 0) {
unsigned int npcap_major, npcap_minor;
if (caplibs_get_npcap_version(&npcap_major, &npcap_minor)) {
if (npcap_major == 1 &&
(npcap_minor >= 71 && npcap_minor <= 73)) {
return
"This is a bug in your version of Npcap.\n"
"\n"
"If you need to use promiscuous mode, you must upgrade to the current "
"version of Npcap, which is available from https://npcap.com/\n"
"\n"
"Otherwise, turn off promiscuous mode for this device.";
}
}
return
"Please turn off promiscuous mode for this device.";
}
return NULL;
}
#elif defined(__linux__)
static const char *
get_platform_pcap_failure_secondary_error_message(const char *open_status_str)
{
/*
* The error string is the message provided by libpcap on
* Linux if an attempt to open a PF_PACKET socket failed
* with EAFNOSUPPORT. This probably means that either 1)
* the kernel doesn't have PF_PACKET support configured in
* or 2) this is a Flatpak version of Wireshark that's been
* sandboxed in a way that disallows opening PF_PACKET
* sockets.
*
* Suggest that the user find some other package of
* Wireshark if they want to capture traffic and are
* running a Flatpak of Wireshark or that they configure
* PF_PACKET support back in if it's configured out.
*/
static const char af_notsup[] =
"socket: Address family not supported by protocol";
if (strcmp(open_status_str, af_notsup) == 0) {
return
"If you are running Wireshark from a Flatpak package, "
"it does not support packet capture; you will need "
"to run a different version of Wireshark in order "
"to capture traffic.\n"
"\n"
"Otherwise, if your machine is running a kernel that "
"was not configured with CONFIG_PACKET, that kernel "
"does not support packet capture; you will need to "
"use a kernel configured with CONFIG_PACKET.";
}
return NULL;
}
#else
static const char *
get_platform_pcap_failure_secondary_error_message(const char *open_status_str _U_)
{
/* No such message for platforms not handled above. */
return NULL;
}
#endif
const char *
get_pcap_failure_secondary_error_message(cap_device_open_status open_status,
const char *open_status_str)
{
const char *platform_secondary_error_message;
#ifdef _WIN32
/*
* On Windows, first make sure they *have* Npcap installed.
*/
if (!has_npcap) {
return
"In order to capture packets, Npcap must be installed. See\n"
"\n"
" https://npcap.com/\n"
"\n"
"for a downloadable version of Npcap and for instructions on how to\n"
"install it.";
}
#endif
/*
* OK, now just return a largely platform-independent error that might
* have platform-specific suggestions at the end (for example, suggestions
* for how to get permission to capture).
*/
switch (open_status) {
case CAP_DEVICE_OPEN_NO_ERR:
case CAP_DEVICE_OPEN_WARNING_PROMISC_NOTSUP:
case CAP_DEVICE_OPEN_WARNING_TSTAMP_TYPE_NOTSUP:
case CAP_DEVICE_OPEN_WARNING_OTHER:
/* This should not happen, as those aren't errors. */
return "";
case CAP_DEVICE_OPEN_ERROR_NO_SUCH_DEVICE:
case CAP_DEVICE_OPEN_ERROR_RFMON_NOTSUP:
case CAP_DEVICE_OPEN_ERROR_IFACE_NOT_UP:
/*
* Not clear what suggestions to make for these cases.
*/
return "";
case CAP_DEVICE_OPEN_ERROR_PERM_DENIED:
case CAP_DEVICE_OPEN_ERROR_PROMISC_PERM_DENIED:
/*
* This is a permissions error, so no need to specify any other
* warnings.
*/
return
"Please check to make sure you have sufficient permissions."
PLATFORM_PERMISSIONS_SUGGESTION;
break;
case CAP_DEVICE_OPEN_ERROR_OTHER:
case CAP_DEVICE_OPEN_ERROR_GENERIC:
/*
* We don't know what kind of error it is. See if there's a hint
* in the error string; if not, throw all generic suggestions at
* the user.
*
* First, check for some text that pops up in some errors.
* Do platform-specific checks first.
*/
platform_secondary_error_message =
get_platform_pcap_failure_secondary_error_message(open_status_str);
if (platform_secondary_error_message != NULL) {
/* We got one, so return it. */
return platform_secondary_error_message;
}
/*
* Not one of those particular problems. Was this a "generic"
* error from pcap_open_live() or pcap_open(), in which case
* it might be a permissions error?
*/
if (open_status == CAP_DEVICE_OPEN_ERROR_GENERIC) {
/* Yes. */
return
"Please check to make sure you have sufficient permissions, and that you have "
"the proper interface or pipe specified."
PLATFORM_PERMISSIONS_SUGGESTION;
} else {
/*
* This is not a permissions error, so no need to suggest
* checking permissions.
*/
return
"Please check that you have the proper interface or pipe specified.";
}
break;
default:
/*
* This is not a permissions error, so no need to suggest
* checking permissions.
*/
return
"Please check that you have the proper interface or pipe specified.";
break;
}
}
#endif /* HAVE_LIBPCAP */
/*
* Editor modelines - https://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:
*/