nexmon – Rev 1
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/* extcap.c
*
* Routines for extcap external capture
* Copyright 2013, Mike Ryan <mikeryan@lacklustre.net>
*
* 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef _WIN32
#include <windows.h>
#include <process.h>
#include <time.h>
#else
/* Include for unlink */
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#include <glib.h>
#include <log.h>
#include <epan/prefs.h>
#include <epan/prefs-int.h>
#include <wsutil/file_util.h>
#include <wsutil/filesystem.h>
#include <wsutil/tempfile.h>
#include "capture_opts.h"
#include "extcap.h"
#include "extcap_parser.h"
#include "extcap_spawn.h"
#ifdef _WIN32
static HANDLE pipe_h = NULL;
#endif
static void extcap_child_watch_cb(GPid pid, gint status, gpointer user_data);
/* internal container, for all the extcap interfaces that have been found.
* will be resetted by every call to extcap_interface_list() and is being
* used in extcap_get_if_* as well as extcap_init_interfaces to ensure,
* that only extcap interfaces are being given to underlying extcap programs
*/
static GHashTable *ifaces = NULL;
/* internal container, for all the extcap executables that have been found.
* will be resetted by every call to extcap_interface_list() and is being
* used for printing information about all extcap interfaces found
*/
static GHashTable *tools = NULL;
/* internal container, to map preference names to pointers that hold preference
* values. These ensure that preferences can survive extcap if garbage
* collection, and does not lead to dangling pointers in the prefs subsystem.
*/
static GHashTable *extcap_prefs_dynamic_vals = NULL;
/* Callback definition for extcap_foreach */
typedef gboolean (*extcap_cb_t)(const gchar *extcap, const gchar *ifname, gchar *output, void *data,
gchar **err_str);
/* #define ARG_DEBUG */
#if ARG_DEBUG
static void extcap_debug_arguments ( extcap_arg *arg_iter );
#endif
static gboolean
extcap_if_exists(const gchar *ifname)
{
if ( !ifname || !ifaces )
return FALSE;
if ( g_hash_table_lookup(ifaces, ifname) )
return TRUE;
return FALSE;
}
static gboolean
extcap_if_exists_for_extcap(const gchar *ifname, const gchar *extcap)
{
gchar *entry = (gchar *)g_hash_table_lookup(ifaces, ifname);
if ( entry && strcmp(entry, extcap) == 0 )
return TRUE;
return FALSE;
}
static gchar *
extcap_if_executable(const gchar *ifname)
{
return (gchar *)g_hash_table_lookup(ifaces, ifname);
}
static void
extcap_if_add(const gchar *ifname, const gchar *extcap)
{
if ( !g_hash_table_lookup(ifaces, ifname) )
g_hash_table_insert(ifaces, g_strdup(ifname), g_strdup(extcap));
}
static void
extcap_free_info (gpointer data) {
extcap_info * info = (extcap_info *)data;
g_free (info->basename);
g_free (info->full_path);
g_free (info->version);
g_free (info);
}
static void
extcap_tool_add(const gchar *extcap, const extcap_interface *interface)
{
char *toolname;
if ( !extcap || !interface )
return;
toolname = g_path_get_basename(extcap);
if ( !g_hash_table_lookup(tools, toolname) ) {
extcap_info * store = (extcap_info *)g_new0(extcap_info, 1);
store->version = g_strdup(interface->version);
store->full_path = g_strdup(extcap);
store->basename = g_strdup(toolname);
g_hash_table_insert(tools, g_strdup(toolname), store);
}
g_free(toolname);
}
/* Note: args does not need to be NULL-terminated. */
static void extcap_foreach(gint argc, gchar **args, extcap_cb_t cb,
void *cb_data, char **err_str, const char * ifname _U_) {
const char *dirname = get_extcap_dir();
GDir *dir;
const gchar *file;
gboolean keep_going;
keep_going = TRUE;
if ((dir = g_dir_open(dirname, 0, NULL)) != NULL) {
GString *extcap_path = NULL;
extcap_path = g_string_new("");
while (keep_going && (file = g_dir_read_name(dir)) != NULL ) {
gchar *command_output = NULL;
/* full path to extcap binary */
#ifdef _WIN32
g_string_printf(extcap_path, "%s\\%s", dirname, file);
#else
g_string_printf(extcap_path, "%s/%s", dirname, file);
#endif
if ( extcap_if_exists(ifname) && !extcap_if_exists_for_extcap(ifname, extcap_path->str ) )
continue;
if ( extcap_spawn_sync ( (gchar *) dirname, extcap_path->str, argc, args, &command_output ) )
keep_going = cb(extcap_path->str, ifname, command_output, cb_data, err_str);
g_free(command_output);
}
g_dir_close(dir);
g_string_free(extcap_path, TRUE);
}
}
static gboolean dlt_cb(const gchar *extcap _U_, const gchar *ifname _U_, gchar *output, void *data,
char **err_str) {
extcap_token_sentence *tokens;
extcap_dlt *dlts, *dlt_iter, *next;
if_capabilities_t *caps;
GList *linktype_list = NULL;
data_link_info_t *data_link_info;
tokens = extcap_tokenize_sentences(output);
extcap_parse_dlts(tokens, &dlts);
extcap_free_tokenized_sentence_list(tokens);
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap pipe %s ", extcap);
/*
* Allocate the interface capabilities structure.
*/
caps = (if_capabilities_t *) g_malloc(sizeof *caps);
caps->can_set_rfmon = FALSE;
dlt_iter = dlts;
while (dlt_iter != NULL ) {
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
" DLT %d name=\"%s\" display=\"%s\" ", dlt_iter->number,
dlt_iter->name, dlt_iter->display);
data_link_info = g_new(data_link_info_t, 1);
data_link_info->dlt = dlt_iter->number;
data_link_info->name = g_strdup(dlt_iter->name);
data_link_info->description = g_strdup(dlt_iter->display);
linktype_list = g_list_append(linktype_list, data_link_info);
dlt_iter = dlt_iter->next_dlt;
}
/* Check to see if we built a list */
if (linktype_list != NULL && data != NULL) {
caps->data_link_types = linktype_list;
*(if_capabilities_t **) data = caps;
} else {
if (err_str) {
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, " returned no DLTs");
*err_str = g_strdup("Extcap returned no DLTs");
}
g_free(caps);
}
dlt_iter = dlts;
while (dlt_iter != NULL ) {
next = dlt_iter->next_dlt;
extcap_free_dlt(dlt_iter);
dlt_iter = next;
}
return FALSE;
}
if_capabilities_t *
extcap_get_if_dlts(const gchar *ifname, char **err_str) {
gchar *argv[3];
gint i;
if_capabilities_t *caps = NULL;
if (err_str != NULL)
*err_str = NULL;
if ( extcap_if_exists(ifname) )
{
argv[0] = g_strdup(EXTCAP_ARGUMENT_LIST_DLTS);
argv[1] = g_strdup(EXTCAP_ARGUMENT_INTERFACE);
argv[2] = g_strdup(ifname);
extcap_foreach(3, argv, dlt_cb, &caps, err_str, ifname);
for (i = 0; i < 3; ++i)
g_free(argv[i]);
}
return caps;
}
static gboolean interfaces_cb(const gchar *extcap, const gchar *ifname _U_, gchar *output, void *data,
char **err_str _U_) {
GList **il = (GList **) data;
extcap_token_sentence *tokens;
extcap_interface *interfaces, *int_iter; /*, *next; */
if_info_t *if_info;
tokens = extcap_tokenize_sentences(output);
extcap_parse_interfaces(tokens, &interfaces);
extcap_free_tokenized_sentence_list(tokens);
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap pipe %s ", extcap);
int_iter = interfaces;
while (int_iter != NULL ) {
if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE && extcap_if_exists(int_iter->call) )
{
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_WARNING, "Extcap interface \"%s\" is already provided by \"%s\" ",
int_iter->call, (gchar *)extcap_if_executable(int_iter->call) );
int_iter = int_iter->next_interface;
continue;
}
if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE )
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, " Interface [%s] \"%s\" ",
int_iter->call, int_iter->display);
else if ( int_iter->if_type == EXTCAP_SENTENCE_EXTCAP )
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, " Extcap [%s] ", int_iter->call);
if ( int_iter->if_type == EXTCAP_SENTENCE_INTERFACE ) {
if (il != NULL) {
if_info = g_new0(if_info_t, 1);
if_info->name = g_strdup(int_iter->call);
if_info->friendly_name = g_strdup(int_iter->display);
if_info->type = IF_EXTCAP;
if_info->extcap = g_strdup(extcap);
*il = g_list_append(*il, if_info);
}
extcap_if_add(int_iter->call, extcap);
}
/* Call for interfaces and tools alike. Multiple calls (because a tool has multiple
* interfaces) are handled internally */
extcap_tool_add(extcap, int_iter);
int_iter = int_iter->next_interface;
}
extcap_free_interface(interfaces);
return TRUE;
}
static gint
if_info_compare(gconstpointer a, gconstpointer b)
{
gint comp = 0;
const if_info_t * if_a = (const if_info_t *)a;
const if_info_t * if_b = (const if_info_t *)b;
if ( (comp = g_strcmp0(if_a->name, if_b->name)) == 0 )
return g_strcmp0(if_a->friendly_name, if_b->friendly_name);
return comp;
}
static void
extcap_reload_interface_list(GList **retp, char **err_str) {
gchar *argv;
if (err_str != NULL)
*err_str = NULL;
/* ifaces is used as cache, do not destroy its contents when
* returning or no extcap interfaces can be queried for options */
if (ifaces == NULL)
ifaces = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_free);
else
g_hash_table_remove_all(ifaces);
if (tools == NULL)
tools = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, extcap_free_info);
else
g_hash_table_remove_all(tools);
argv = g_strdup(EXTCAP_ARGUMENT_LIST_INTERFACES);
extcap_foreach(1, &argv, interfaces_cb, retp, err_str, NULL);
g_free(argv);
}
GHashTable *
extcap_tools_list(void) {
if ( tools == NULL || g_hash_table_size(tools) == 0 )
extcap_reload_interface_list(NULL, NULL);
return tools;
}
GList *
append_extcap_interface_list(GList *list, char **err_str) {
GList *ret = NULL;
GList *entry;
void *data;
/* Update the extcap interfaces and get a list of their if_infos */
extcap_reload_interface_list(&ret, err_str);
/* Sort that list */
ret = g_list_sort(ret, if_info_compare);
/* Append the interfaces in that list to the list we're handed. */
while (ret != NULL) {
entry = g_list_first(ret);
data = entry->data;
ret = g_list_delete_link(ret, entry);
list = g_list_append(list, data);
}
return list;
}
static void extcap_free_arg_elem(gpointer data, gpointer user_data _U_) {
extcap_free_arg((extcap_arg *) data);
g_free(data);
}
void extcap_register_preferences(void)
{
GList * interfaces = NULL;
module_t * dev_module = prefs_find_module("extcap");
if ( !dev_module )
return;
if ( ! ifaces || g_hash_table_size(ifaces) == 0 )
extcap_reload_interface_list(NULL, NULL);
interfaces = g_hash_table_get_keys(ifaces);
while ( interfaces ) {
extcap_get_if_configuration((gchar *)interfaces->data);
interfaces = g_list_next(interfaces);
}
}
/**
* Releases the dynamic preference value pointers. Must not be called before
* prefs_cleanup since these pointers could still be in use.
*/
void extcap_cleanup(void)
{
if (extcap_prefs_dynamic_vals) {
g_hash_table_destroy(extcap_prefs_dynamic_vals);
}
}
void extcap_pref_store(extcap_arg * arg, const char * newval)
{
if (arg && arg->pref_valptr != NULL)
{
g_free(*arg->pref_valptr);
*arg->pref_valptr = g_strdup(newval);
}
}
/**
* Obtains a pointer which can store a value for the given preference name.
*
* Extcap interfaces (and their preferences) are dynamic, they can be created
* and destroyed at will. Thus their data structures are insufficient to pass to
* the preferences APIs which require pointers which are valid until the
* preferences are removed (at exit).
*/
static gchar ** extcap_prefs_dynamic_valptr(const char *name)
{
gchar **valp;
if (!extcap_prefs_dynamic_vals) {
/* Initialize table only as needed, most preferences are not dynamic */
extcap_prefs_dynamic_vals = g_hash_table_new_full(g_str_hash, g_str_equal,
g_free, g_free);
}
valp = (gchar **)g_hash_table_lookup(extcap_prefs_dynamic_vals, name);
if (!valp) {
/* New dynamic pref, allocate, initialize and store. */
valp = g_new0(gchar *, 1);
g_hash_table_insert(extcap_prefs_dynamic_vals, g_strdup(name), valp);
}
return valp;
}
static void extcap_free_if_configuration(GList *list)
{
GList *elem, *sl;
for (elem = g_list_first(list); elem; elem = elem->next)
{
if (elem->data != NULL) {
/* g_list_free_full() only exists since 2.28. */
sl = g_list_first((GList *)elem->data);
g_list_foreach(sl, (GFunc)extcap_free_arg_elem, NULL);
g_list_free(sl);
}
}
g_list_free(list);
}
struct preference *
extcap_pref_for_argument(const gchar *ifname, struct _extcap_arg * arg) {
struct preference * pref = NULL;
GRegex * regex_name = g_regex_new ("[-]+", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
GRegex * regex_ifname = g_regex_new ("(?![a-zA-Z1-9_]).", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
if (regex_name && regex_ifname) {
if ( prefs_find_module("extcap") ) {
gchar * pref_name = g_regex_replace(regex_name, arg->call, strlen(arg->call), 0, "", (GRegexMatchFlags) 0, NULL );
gchar * ifname_underscore = g_regex_replace(regex_ifname, ifname, strlen(ifname), 0, "_", (GRegexMatchFlags) 0, NULL );
gchar * ifname_lowercase = g_ascii_strdown(ifname_underscore, -1);
gchar * pref_ifname = g_strconcat(ifname_lowercase, ".", pref_name, NULL);
pref = prefs_find_preference(prefs_find_module("extcap"), pref_ifname);
g_free(pref_name);
g_free(ifname_underscore);
g_free(ifname_lowercase);
g_free(pref_ifname);
}
}
if (regex_name) {
g_regex_unref(regex_name);
}
if (regex_ifname) {
g_regex_unref(regex_ifname);
}
return pref;
}
static gboolean search_cb(const gchar *extcap _U_, const gchar *ifname _U_, gchar *output, void *data,
char **err_str _U_) {
extcap_token_sentence *tokens = NULL;
GList *arguments = NULL;
GList **il = (GList **) data;
module_t * dev_module = NULL;
tokens = extcap_tokenize_sentences(output);
arguments = extcap_parse_args(tokens);
extcap_free_tokenized_sentence_list(tokens);
#if ARG_DEBUG
extcap_debug_arguments ( arguments );
#endif
dev_module = prefs_find_module("extcap");
if ( dev_module ) {
GList * walker = arguments;
GRegex * regex_name = g_regex_new ("[-]+", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
GRegex * regex_ifname = g_regex_new ("(?![a-zA-Z1-9_]).", (GRegexCompileFlags) 0, (GRegexMatchFlags) 0, NULL );
if (regex_name && regex_ifname) {
while ( walker != NULL ) {
extcap_arg * arg = (extcap_arg *)walker->data;
arg->device_name = g_strdup(ifname);
if ( arg->save ) {
struct preference * pref = NULL;
gchar * pref_name = g_regex_replace(regex_name, arg->call, strlen(arg->call), 0, "", (GRegexMatchFlags) 0, NULL );
gchar * ifname_underscore = g_regex_replace(regex_ifname, ifname, strlen(ifname), 0, "_", (GRegexMatchFlags) 0, NULL );
gchar * ifname_lowercase = g_ascii_strdown(ifname_underscore, -1);
gchar * pref_ifname = g_strconcat(ifname_lowercase, ".", pref_name, NULL);
if ( ( pref = prefs_find_preference(dev_module, pref_ifname) ) == NULL ) {
arg->pref_valptr = extcap_prefs_dynamic_valptr(pref_ifname);
/* Set an initial value if any (the string will be copied at registration) */
if (arg->default_complex) {
*arg->pref_valptr = arg->default_complex->_val;
}
prefs_register_string_preference(dev_module, g_strdup(pref_ifname),
arg->display, arg->display, (const char **)arg->pref_valptr);
} else {
/* Been here before, restore stored value */
if (! arg->pref_valptr && pref->varp.string && strlen(*pref->varp.string))
{
arg->pref_valptr = pref->varp.string;
}
}
g_free(pref_name);
g_free(ifname_underscore);
g_free(ifname_lowercase);
g_free(pref_ifname);
}
walker = g_list_next(walker);
}
}
if (regex_name) {
g_regex_unref(regex_name);
}
if (regex_ifname) {
g_regex_unref(regex_ifname);
}
}
*il = g_list_append(*il, arguments);
/* By returning false, extcap_foreach will break on first found */
return TRUE;
}
GList *
extcap_get_if_configuration(const char * ifname) {
gchar *argv[3];
GList *ret = NULL;
gchar **err_str = NULL;
int i;
if ( extcap_if_exists(ifname) )
{
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "Extcap path %s",
get_extcap_dir());
argv[0] = g_strdup(EXTCAP_ARGUMENT_CONFIG);
argv[1] = g_strdup(EXTCAP_ARGUMENT_INTERFACE);
argv[2] = g_strdup(ifname);
extcap_foreach(3, argv, search_cb, &ret, err_str, ifname);
for (i = 0; i < 3; i++)
g_free(argv[i]);
}
return ret;
}
/**
* If is_required is FALSE: returns TRUE if the extcap interface has
* configurable options.
* If is_required is TRUE: returns TRUE when the extcap interface has
* configurable options that required modification. (For example, when an
* argument is required but empty.)
*/
gboolean
extcap_has_configuration(const char * ifname, gboolean is_required) {
GList * arguments = 0;
GList * walker = 0, * item = 0;
gboolean found = FALSE;
arguments = extcap_get_if_configuration((const char *)( ifname ) );
walker = g_list_first(arguments);
while ( walker != NULL && ! found ) {
item = g_list_first((GList *)(walker->data));
while ( item != NULL && ! found ) {
if ( (extcap_arg *)(item->data) != NULL ) {
extcap_arg * arg = (extcap_arg *)(item->data);
/* Should required options be present, or any kind of options */
if ( ! is_required )
found = TRUE;
else if ( arg->is_required ) {
const gchar * stored = NULL;
const gchar * defval = NULL;
if (arg->pref_valptr != NULL)
stored = *arg->pref_valptr;
if ( arg->default_complex != NULL && arg->default_complex->_val != NULL )
defval = arg->default_complex->_val;
if ( arg->is_required ) {
/* If stored and defval is identical and the argument is required,
* configuration is needed */
if ( defval && stored && g_strcmp0(stored, defval) == 0 )
found = TRUE;
else if ( ! defval && (!stored || !*stored) )
found = TRUE;
}
if ( arg->arg_type == EXTCAP_ARG_FILESELECT ) {
if ( arg->fileexists && ! ( file_exists(defval) || file_exists(stored) ) )
found = TRUE;
}
}
}
item = item->next;
}
walker = walker->next;
}
extcap_free_if_configuration(arguments);
return found;
}
/* taken from capchild/capture_sync.c */
static gboolean pipe_data_available(int pipe_fd) {
#ifdef _WIN32 /* PeekNamedPipe */
HANDLE hPipe = (HANDLE) _get_osfhandle(pipe_fd);
DWORD bytes_avail;
if (hPipe == INVALID_HANDLE_VALUE)
return FALSE;
if (! PeekNamedPipe(hPipe, NULL, 0, NULL, &bytes_avail, NULL))
return FALSE;
if (bytes_avail > 0)
return TRUE;
return FALSE;
#else /* select */
fd_set rfds;
struct timeval timeout;
FD_ZERO(&rfds);
FD_SET(pipe_fd, &rfds);
timeout.tv_sec = 0;
timeout.tv_usec = 0;
if (select(pipe_fd+1, &rfds, NULL, NULL, &timeout) > 0)
return TRUE;
return FALSE;
#endif
}
void extcap_if_cleanup(capture_options * capture_opts, gchar ** errormsg) {
interface_options interface_opts;
extcap_userdata * userdata;
guint icnt = 0;
gboolean overwrite_exitcode;
gchar * buffer;
#define STDERR_BUFFER_SIZE 1024
for (icnt = 0; icnt < capture_opts->ifaces->len; icnt++) {
interface_opts = g_array_index(capture_opts->ifaces, interface_options,
icnt);
/* skip native interfaces */
if (interface_opts.if_type != IF_EXTCAP)
continue;
overwrite_exitcode = FALSE;
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
"Extcap [%s] - Cleaning up fifo: %s; PID: %d", interface_opts.name,
interface_opts.extcap_fifo, interface_opts.extcap_pid);
#ifdef _WIN32
if (pipe_h)
{
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
"Extcap [%s] - Closing pipe", interface_opts.name);
FlushFileBuffers(pipe_h);
DisconnectNamedPipe(pipe_h);
CloseHandle(pipe_h);
}
#else
if (interface_opts.extcap_fifo != NULL && file_exists(interface_opts.extcap_fifo))
{
/* the fifo will not be freed here, but with the other capture_opts in capture_sync */
ws_unlink(interface_opts.extcap_fifo);
interface_opts.extcap_fifo = NULL;
}
#endif
/* Maybe the client closed and removed fifo, but ws should check if
* pid should be closed */
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
"Extcap [%s] - Closing spawned PID: %d", interface_opts.name,
interface_opts.extcap_pid);
userdata = (extcap_userdata *) interface_opts.extcap_userdata;
if ( userdata )
{
if (userdata->extcap_stderr_rd > 0 && pipe_data_available(userdata->extcap_stderr_rd) )
{
buffer = (gchar * )g_malloc0(sizeof(gchar) * STDERR_BUFFER_SIZE + 1);
#ifdef _WIN32
win32_readfrompipe((HANDLE)_get_osfhandle(userdata->extcap_stderr_rd), STDERR_BUFFER_SIZE, buffer);
#else
if (read(userdata->extcap_stderr_rd, buffer, sizeof(gchar) * STDERR_BUFFER_SIZE) <= 0 )
buffer[0] = '\0';
#endif
if ( strlen ( buffer) > 0 )
{
userdata->extcap_stderr = g_strdup_printf("%s", buffer);
userdata->exitcode = 1;
}
g_free(buffer);
}
#ifndef _WIN32
/* Final child watch may not have been called */
if ( interface_opts.extcap_child_watch != 0 )
{
extcap_child_watch_cb(userdata->pid, 0, capture_opts);
/* it will have changed in extcap_child_watch_cb */
interface_opts = g_array_index(capture_opts->ifaces, interface_options,
icnt);
}
#endif
if ( userdata->extcap_stderr != NULL )
overwrite_exitcode = TRUE;
if ( overwrite_exitcode || userdata->exitcode != 0 )
{
if ( userdata->extcap_stderr != 0 )
{
if ( *errormsg == NULL )
*errormsg = g_strdup_printf("Error by extcap pipe: %s", userdata->extcap_stderr);
else
{
gchar * temp = g_strconcat ( *errormsg, "\nError by extcap pipe: " ,userdata->extcap_stderr, NULL );
g_free(*errormsg);
*errormsg = temp;
}
g_free (userdata->extcap_stderr );
}
userdata->extcap_stderr = NULL;
userdata->exitcode = 0;
}
}
if (interface_opts.extcap_child_watch > 0)
{
g_source_remove(interface_opts.extcap_child_watch);
interface_opts.extcap_child_watch = 0;
}
if (interface_opts.extcap_pid != INVALID_EXTCAP_PID)
{
#ifdef _WIN32
TerminateProcess(interface_opts.extcap_pid, 0);
#endif
g_spawn_close_pid(interface_opts.extcap_pid);
interface_opts.extcap_pid = INVALID_EXTCAP_PID;
g_free(interface_opts.extcap_userdata);
interface_opts.extcap_userdata = NULL;
}
/* Make sure modified interface_opts is saved in capture_opts. */
capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, icnt);
g_array_insert_val(capture_opts->ifaces, icnt, interface_opts);
}
}
static gboolean
extcap_add_arg_and_remove_cb(gpointer key, gpointer value, gpointer data) {
GPtrArray *args = (GPtrArray *)data;
if ( key != NULL )
{
g_ptr_array_add(args, g_strdup((const gchar*)key));
if ( value != NULL )
g_ptr_array_add(args, g_strdup((const gchar*)value));
return TRUE;
}
return FALSE;
}
void extcap_child_watch_cb(GPid pid, gint status, gpointer user_data)
{
guint i;
interface_options interface_opts;
extcap_userdata * userdata = NULL;
capture_options * capture_opts = (capture_options *)(user_data);
if ( capture_opts == NULL || capture_opts->ifaces == NULL || capture_opts->ifaces->len == 0 )
return;
/* Close handle to child process. */
g_spawn_close_pid(pid);
/* Update extcap_pid in interface options structure. */
for (i = 0; i < capture_opts->ifaces->len; i++)
{
interface_opts = g_array_index(capture_opts->ifaces, interface_options, i);
if (interface_opts.extcap_pid == pid)
{
userdata = (extcap_userdata *)interface_opts.extcap_userdata;
if ( userdata != NULL )
{
interface_opts.extcap_pid = INVALID_EXTCAP_PID;
userdata->exitcode = 0;
#ifndef _WIN32
if ( WIFEXITED(status) )
{
if ( WEXITSTATUS(status) != 0 )
userdata->exitcode = WEXITSTATUS(status);
}
else
userdata->exitcode = G_SPAWN_ERROR_FAILED;
#else
if (status != 0)
userdata->exitcode = status;
#endif
if ( status == 0 && userdata->extcap_stderr != NULL )
userdata->exitcode = 1;
}
g_source_remove(interface_opts.extcap_child_watch);
interface_opts.extcap_child_watch = 0;
capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, i);
g_array_insert_val(capture_opts->ifaces, i, interface_opts);
break;
}
}
}
static
GPtrArray * extcap_prepare_arguments(interface_options interface_opts)
{
GPtrArray *result = NULL;
#if ARG_DEBUG
gchar **tmp;
int tmp_i;
#endif
if (interface_opts.if_type == IF_EXTCAP )
{
result = g_ptr_array_new();
#define add_arg(X) g_ptr_array_add(result, g_strdup(X))
add_arg(interface_opts.extcap);
add_arg(EXTCAP_ARGUMENT_RUN_CAPTURE);
add_arg(EXTCAP_ARGUMENT_INTERFACE);
add_arg(interface_opts.name);
if (interface_opts.cfilter && strlen(interface_opts.cfilter) > 0) {
add_arg(EXTCAP_ARGUMENT_CAPTURE_FILTER);
add_arg(interface_opts.cfilter);
}
add_arg(EXTCAP_ARGUMENT_RUN_PIPE);
add_arg(interface_opts.extcap_fifo);
if (interface_opts.extcap_args == NULL || g_hash_table_size(interface_opts.extcap_args) == 0)
{
/* User did not perform interface configuration.
*
* Check if there are any boolean flags that are set by default
* and hence their argument should be added.
*/
GList *arglist;
GList *elem;
arglist = extcap_get_if_configuration(interface_opts.name);
for (elem = g_list_first(arglist); elem; elem = elem->next)
{
GList * arg_list;
extcap_arg *arg_iter;
if (elem->data == NULL)
{
continue;
}
arg_list = g_list_first((GList *)elem->data);
while (arg_list != NULL) {
const gchar * stored = NULL, * defval = NULL;
/* In case of boolflags only first element in arg_list is relevant. */
arg_iter = (extcap_arg*) (arg_list->data);
if (arg_iter->pref_valptr != NULL)
stored = *arg_iter->pref_valptr;
if ( arg_iter->default_complex != NULL && arg_iter->default_complex->_val != NULL )
defval = arg_iter->default_complex->_val;
/* Different data in storage then set for default */
if ( g_strcmp0(stored, defval) != 0 ) {
if ( arg_iter->arg_type == EXTCAP_ARG_BOOLFLAG ) {
if ( g_strcmp0(stored, "true") == 0 )
add_arg(arg_iter->call);
} else {
add_arg(arg_iter->call);
add_arg(stored);
}
} else if (arg_iter->arg_type == EXTCAP_ARG_BOOLFLAG) {
if (extcap_complex_get_bool(arg_iter->default_complex))
add_arg(arg_iter->call);
}
arg_list = arg_list->next;
}
}
extcap_free_if_configuration(arglist);
}
else
{
g_hash_table_foreach_remove(interface_opts.extcap_args, extcap_add_arg_and_remove_cb, result);
}
add_arg(NULL);
#undef add_arg
#if ARG_DEBUG
/* Dump commandline parameters sent to extcap. */
for (tmp = (gchar **)result->pdata, tmp_i = 0; *tmp && **tmp; ++tmp_i, ++tmp)
{
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG, "argv[%d]: %s", tmp_i, *tmp);
}
#endif
}
return result;
}
/* call mkfifo for each extcap,
* returns FALSE if there's an error creating a FIFO */
gboolean
extcap_init_interfaces(capture_options *capture_opts)
{
guint i;
interface_options interface_opts;
extcap_userdata * userdata;
for (i = 0; i < capture_opts->ifaces->len; i++)
{
GPtrArray *args = NULL;
GPid pid = INVALID_EXTCAP_PID;
interface_opts = g_array_index(capture_opts->ifaces, interface_options, i);
/* skip native interfaces */
if (interface_opts.if_type != IF_EXTCAP )
continue;
/* create pipe for fifo */
if ( ! extcap_create_pipe ( &interface_opts.extcap_fifo ) )
return FALSE;
/* Create extcap call */
args = extcap_prepare_arguments(interface_opts);
userdata = g_new0(extcap_userdata, 1);
pid = extcap_spawn_async(userdata, args );
g_ptr_array_foreach(args, (GFunc)g_free, NULL);
g_ptr_array_free(args, TRUE);
if ( pid == INVALID_EXTCAP_PID )
{
g_free(userdata);
continue;
}
interface_opts.extcap_pid = pid;
interface_opts.extcap_child_watch =
g_child_watch_add(pid, extcap_child_watch_cb, (gpointer)capture_opts);
#ifdef _WIN32
/* On Windows, wait for extcap to connect to named pipe.
* Some extcaps will present UAC screen to user.
* 30 second timeout should be reasonable timeout for extcap to
* connect to named pipe (including user interaction).
* Wait on multiple object in case of extcap termination
* without opening pipe.
*
* Minimum supported version of Windows: XP / Server 2003.
*/
if (pid != INVALID_EXTCAP_PID)
{
extcap_wait_for_pipe(pipe_h, pid);
}
#endif
interface_opts.extcap_userdata = (gpointer) userdata;
capture_opts->ifaces = g_array_remove_index(capture_opts->ifaces, i);
g_array_insert_val(capture_opts->ifaces, i, interface_opts);
}
return TRUE;
}
#ifdef _WIN32
/* called by capture_sync to get the CreatNamedPipe handle*/
HANDLE
extcap_get_win32_handle()
{
return pipe_h;
}
#endif
gboolean extcap_create_pipe(char ** fifo)
{
#ifdef _WIN32
gchar timestr[ 14+1 ];
time_t current_time;
gchar *pipename = NULL;
SECURITY_ATTRIBUTES security;
/* create pipename */
current_time = time(NULL);
/*
* XXX - we trust Windows not to return a time before the Epoch here,
* so we won't get a null pointer back from localtime().
*/
strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(¤t_time));
pipename = g_strconcat ( "\\\\.\\pipe\\", EXTCAP_PIPE_PREFIX, "_", timestr, NULL );
/* Security struct to enable Inheritable HANDLE */
memset(&security, 0, sizeof(SECURITY_ATTRIBUTES));
security.nLength = sizeof(SECURITY_ATTRIBUTES);
security.bInheritHandle = TRUE;
security.lpSecurityDescriptor = NULL;
/* create a namedPipe*/
pipe_h = CreateNamedPipe(
utf_8to16(pipename),
PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,
PIPE_TYPE_MESSAGE| PIPE_READMODE_MESSAGE | PIPE_WAIT,
5, 65536, 65536,
300,
&security);
if (pipe_h == INVALID_HANDLE_VALUE)
{
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,"\nError creating pipe => (%d)", GetLastError());
return FALSE;
}
else
{
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,"\nWireshark Created pipe =>(%s)",pipename);
*fifo = g_strdup(pipename);
}
#else
gchar *temp_name = NULL;
int fd = 0;
if ((fd = create_tempfile(&temp_name, EXTCAP_PIPE_PREFIX, NULL)) < 0 )
return FALSE;
ws_close(fd);
g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
"Extcap - Creating fifo: %s", temp_name);
if ( file_exists(temp_name) )
ws_unlink(temp_name);
if (mkfifo(temp_name, 0600) == 0)
*fifo = g_strdup(temp_name);
#endif
return TRUE;
}
#if ARG_DEBUG
void extcap_debug_arguments ( extcap_arg *arg_iter )
{
extcap_value *v = NULL;
GList *walker = NULL;
printf("debug - parser dump\n");
while (arg_iter != NULL) {
printf("ARG %d call=%s display=\"%s\" type=", arg_iter->arg_num, arg_iter->call, arg_iter->display);
switch (arg_iter->arg_type) {
case EXTCAP_ARG_INTEGER:
printf("int\n");
break;
case EXTCAP_ARG_UNSIGNED:
printf("unsigned\n");
break;
case EXTCAP_ARG_LONG:
printf("long\n");
break;
case EXTCAP_ARG_DOUBLE:
printf("double\n");
break;
case EXTCAP_ARG_BOOLEAN:
printf("boolean\n");
break;
case EXTCAP_ARG_MENU:
printf("menu\n");
break;
case EXTCAP_ARG_RADIO:
printf("radio\n");
break;
case EXTCAP_ARG_SELECTOR:
printf("selctor\n");
break;
case EXTCAP_ARG_STRING:
printf ( "string\n" );
break;
case EXTCAP_ARG_PASSWORD:
printf ( "PASSWORD\n" );
break;
case EXTCAP_ARG_MULTICHECK:
printf ( "unknown\n" );
break;
case EXTCAP_ARG_UNKNOWN:
printf ( "unknown\n" );
break;
}
if (arg_iter->range_start != NULL && arg_iter->range_end != NULL) {
printf("\tRange: ");
extcap_printf_complex(arg_iter->range_start);
printf(" - ");
extcap_printf_complex(arg_iter->range_end);
printf("\n");
}
for ( walker = g_list_first ( arg_iter->value_list ); walker; walker = walker->next )
{
v = (extcap_value *)walker->data;
if (v->is_default)
printf("*");
printf("\tcall=\"%p\" display=\"%p\"\n", v->call, v->display);
printf("\tcall=\"%s\" display=\"%s\"\n", v->call, v->display);
}
arg_iter = arg_iter->next_arg;
}
}
#endif
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/