/* capture.c * Routines for packet capture * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * SPDX-License-Identifier: GPL-2.0-or-later */ #include "config.h" #ifdef HAVE_LIBPCAP #include #include #include #include #include #include #include "file.h" #include "ui/capture.h" #include "caputils/capture_ifinfo.h" #include #include "ui/capture_info.h" #include "ui/capture_ui_utils.h" #include "ui/util.h" #include "caputils/capture-pcap-util.h" #include #ifdef _WIN32 #include "caputils/capture-wpcap.h" #endif #include "ui/simple_dialog.h" #include "ui/ws_ui_util.h" #include "wsutil/file_util.h" #include "wsutil/str_util.h" #include #include "log.h" typedef struct if_stat_cache_item_s { char *name; struct pcap_stat ps; } if_stat_cache_item_t; struct if_stat_cache_s { int stat_fd; ws_process_id fork_child; GList *cache_list; /* List of if_stat_chache_entry_t */ }; /* this callback mechanism should possibly be replaced by the g_signal_...() stuff (if I only would know how :-) */ typedef struct { capture_callback_t cb_fct; gpointer user_data; } capture_callback_data_t; static GList *capture_callbacks = NULL; static void capture_callback_invoke(int event, capture_session *cap_session) { capture_callback_data_t *cb; GList *cb_item = capture_callbacks; /* there should be at least one interested */ g_assert(cb_item != NULL); while(cb_item != NULL) { cb = (capture_callback_data_t *)cb_item->data; cb->cb_fct(event, cap_session, cb->user_data); cb_item = g_list_next(cb_item); } } void capture_callback_add(capture_callback_t func, gpointer user_data) { capture_callback_data_t *cb; cb = (capture_callback_data_t *)g_malloc(sizeof(capture_callback_data_t)); cb->cb_fct = func; cb->user_data = user_data; capture_callbacks = g_list_prepend(capture_callbacks, cb); } void capture_callback_remove(capture_callback_t func, gpointer user_data) { capture_callback_data_t *cb; GList *cb_item = capture_callbacks; while(cb_item != NULL) { cb = (capture_callback_data_t *)cb_item->data; if(cb->cb_fct == func && cb->user_data == user_data) { capture_callbacks = g_list_remove(capture_callbacks, cb); g_free(cb); return; } cb_item = g_list_next(cb_item); } g_assert_not_reached(); } /** * Start a capture. * * @return TRUE if the capture starts successfully, FALSE otherwise. */ gboolean capture_start(capture_options *capture_opts, capture_session *cap_session, info_data_t* cap_data, void(*update_cb)(void)) { GString *source; cap_session->state = CAPTURE_PREPARING; cap_session->count = 0; g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Start ..."); source = get_iface_list_string(capture_opts, IFLIST_SHOW_FILTER); cf_set_tempfile_source((capture_file *)cap_session->cf, source->str); g_string_free(source, TRUE); /* try to start the capture child process */ if (!sync_pipe_start(capture_opts, cap_session, cap_data, update_cb)) { /* We failed to start the capture child. */ if(capture_opts->save_file != NULL) { g_free(capture_opts->save_file); capture_opts->save_file = NULL; } g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Start failed."); cap_session->state = CAPTURE_STOPPED; return FALSE; } /* the capture child might not respond shortly after bringing it up */ /* (for example: it will block if no input arrives from an input capture pipe (e.g. mkfifo)) */ /* to prevent problems, bring the main GUI into "capture mode" right after a successful */ /* spawn/exec of the capture child, without waiting for any response from it */ capture_callback_invoke(capture_cb_capture_prepared, cap_session); wtap_rec_init(&cap_session->rec); ws_buffer_init(&cap_session->buf, 1514); if (capture_opts->show_info) { cap_session->wtap = NULL; if (cap_data->counts.counts_hash != NULL) { /* Clean up any previous lists of packet counts */ g_hash_table_destroy(cap_data->counts.counts_hash); } cap_data->counts.counts_hash = g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL, g_free); cap_data->counts.other = 0; cap_data->counts.total = 0; cap_data->ui.counts = &cap_data->counts; capture_info_ui_create(&cap_data->ui, cap_session); } return TRUE; } void capture_stop(capture_session *cap_session) { g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Stop ..."); capture_callback_invoke(capture_cb_capture_stopping, cap_session); /* stop the capture child gracefully */ sync_pipe_stop(cap_session); } void capture_kill_child(capture_session *cap_session) { g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_INFO, "Capture Kill"); /* kill the capture child */ sync_pipe_kill(cap_session->fork_child); } /* We've succeeded in doing a (non real-time) capture; try to read it into a new capture file */ static gboolean capture_input_read_all(capture_session *cap_session, gboolean is_tempfile, gboolean drops_known, guint32 drops) { capture_options *capture_opts = cap_session->capture_opts; int err; /* Capture succeeded; attempt to open the capture file. */ if (cf_open((capture_file *)cap_session->cf, capture_opts->save_file, WTAP_TYPE_AUTO, is_tempfile, &err) != CF_OK) { /* We're not doing a capture any more, so we don't have a save file. */ return FALSE; } /* Set the read filter to NULL. */ /* XXX - this is odd here; try to put it somewhere where it fits better */ cf_set_rfcode((capture_file *)cap_session->cf, NULL); /* Get the packet-drop statistics. XXX - there are currently no packet-drop statistics stored in libpcap captures, and that's what we're reading. At some point, we will add support in Wiretap to return packet-drop statistics for capture file formats that store it, and will make "cf_read()" get those statistics from Wiretap. We clear the statistics (marking them as "not known") in "cf_open()", and "cf_read()" will only fetch them and mark them as known if Wiretap supplies them, so if we get the statistics now, after calling "cf_open()" but before calling "cf_read()", the values we store will be used by "cf_read()". If a future libpcap capture file format stores the statistics, we'll put them into the capture file that we write, and will thus not have to set them here - "cf_read()" will get them from the file and use them. */ if (drops_known) { cf_set_drops_known((capture_file *)cap_session->cf, TRUE); /* XXX - on some systems, libpcap doesn't bother filling in "ps_ifdrop" - it doesn't even set it to zero - so we don't bother looking at it. Ideally, libpcap would have an interface that gave us several statistics - perhaps including various interface error statistics - and would tell us which of them it supplies, allowing us to display only the ones it does. */ cf_set_drops((capture_file *)cap_session->cf, drops); } /* read in the packet data */ switch (cf_read((capture_file *)cap_session->cf, FALSE)) { case CF_READ_OK: case CF_READ_ERROR: /* Just because we got an error, that doesn't mean we were unable to read any of the file; we handle what we could get from the file. */ break; case CF_READ_ABORTED: /* User wants to quit program. Exit by leaving the main loop, so that any quit functions we registered get called. */ main_window_quit(); return FALSE; } /* if we didn't capture even a single packet, close the file again */ if(cap_session->count == 0 && !capture_opts->restart) { simple_dialog(ESD_TYPE_INFO, ESD_BTN_OK, "%sNo packets captured.%s\n" "\n" "As no data was captured, closing the %scapture file.\n" "\n" "\n" "Help about capturing can be found at\n" "\n" " https://wiki.wireshark.org/CaptureSetup" #ifdef _WIN32 "\n\n" "Wireless (Wi-Fi/WLAN):\n" "Try to switch off promiscuous mode in the Capture Options" #endif "", simple_dialog_primary_start(), simple_dialog_primary_end(), (cf_is_tempfile((capture_file *)cap_session->cf)) ? "temporary " : ""); cf_close((capture_file *)cap_session->cf); } return TRUE; } static const char * cf_open_error_message(int err, gchar *err_info, gboolean for_writing, int file_type) { const char *errmsg; static char errmsg_errno[1024 + 1]; if (err < 0) { /* Wiretap error. */ switch (err) { case WTAP_ERR_NOT_REGULAR_FILE: errmsg = "The file \"%s\" is a \"special file\" or socket or other non-regular file."; break; case WTAP_ERR_FILE_UNKNOWN_FORMAT: /* Seen only when opening a capture file for reading. */ errmsg = "The file \"%s\" isn't a capture file in a format Wireshark understands."; break; case WTAP_ERR_UNSUPPORTED: /* Seen only when opening a capture file for reading. */ g_snprintf(errmsg_errno, sizeof(errmsg_errno), "The file \"%%s\" contains record data that Wireshark doesn't support.\n" "(%s)", err_info != NULL ? err_info : "no information supplied"); g_free(err_info); errmsg = errmsg_errno; break; case WTAP_ERR_CANT_WRITE_TO_PIPE: /* Seen only when opening a capture file for writing. */ g_snprintf(errmsg_errno, sizeof(errmsg_errno), "The file \"%%s\" is a pipe, and %s capture files can't be " "written to a pipe.", wtap_file_type_subtype_string(file_type)); errmsg = errmsg_errno; break; case WTAP_ERR_UNWRITABLE_FILE_TYPE: /* Seen only when opening a capture file for writing. */ errmsg = "Wireshark doesn't support writing capture files in that format."; break; case WTAP_ERR_UNWRITABLE_ENCAP: /* Seen only when opening a capture file for writing. */ errmsg = "Wireshark can't save this capture in that format."; break; case WTAP_ERR_ENCAP_PER_PACKET_UNSUPPORTED: if (for_writing) errmsg = "Wireshark can't save this capture in that format."; else errmsg = "The file \"%s\" is a capture for a network type that Wireshark doesn't support."; break; case WTAP_ERR_BAD_FILE: /* Seen only when opening a capture file for reading. */ g_snprintf(errmsg_errno, sizeof(errmsg_errno), "The file \"%%s\" appears to be damaged or corrupt.\n" "(%s)", err_info != NULL ? err_info : "no information supplied"); g_free(err_info); errmsg = errmsg_errno; break; case WTAP_ERR_CANT_OPEN: if (for_writing) errmsg = "The file \"%s\" could not be created for some unknown reason."; else errmsg = "The file \"%s\" could not be opened for some unknown reason."; break; case WTAP_ERR_SHORT_READ: errmsg = "The file \"%s\" appears to have been cut short" " in the middle of a packet or other data."; break; case WTAP_ERR_SHORT_WRITE: errmsg = "A full header couldn't be written to the file \"%s\"."; break; case WTAP_ERR_DECOMPRESS: g_snprintf(errmsg_errno, sizeof(errmsg_errno), "The compressed file \"%%s\" appears to be damaged or corrupt.\n" "(%s)", err_info != NULL ? err_info : "no information supplied"); g_free(err_info); errmsg = errmsg_errno; break; case WTAP_ERR_DECOMPRESSION_NOT_SUPPORTED: g_snprintf(errmsg_errno, sizeof(errmsg_errno), "We don't support the form of compression used by the compressed file \"%%s\".\n" "(%s)", err_info != NULL ? err_info : "no information supplied"); g_free(err_info); errmsg = errmsg_errno; break; default: g_snprintf(errmsg_errno, sizeof(errmsg_errno), "The file \"%%s\" could not be %s: %s.", for_writing ? "created" : "opened", wtap_strerror(err)); errmsg = errmsg_errno; break; } } else errmsg = file_open_error_message(err, for_writing); return errmsg; } /* capture child tells us we have a new (or the first) capture file */ gboolean capture_input_new_file(capture_session *cap_session, gchar *new_file) { capture_options *capture_opts = cap_session->capture_opts; gboolean is_tempfile; int err; gchar *err_info; gchar *err_msg; if(cap_session->state == CAPTURE_PREPARING) { g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture started"); } g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "File: \"%s\"", new_file); g_assert(cap_session->state == CAPTURE_PREPARING || cap_session->state == CAPTURE_RUNNING); /* free the old filename */ if(capture_opts->save_file != NULL) { /* we start a new capture file, close the old one (if we had one before). */ /* (we can only have an open capture file in real_time_mode!) */ if( ((capture_file *) cap_session->cf)->state != FILE_CLOSED) { if(capture_opts->real_time_mode) { cap_session->session_will_restart = TRUE; capture_callback_invoke(capture_cb_capture_update_finished, cap_session); cf_finish_tail((capture_file *)cap_session->cf, &cap_session->rec, &cap_session->buf, &err); cf_close((capture_file *)cap_session->cf); } else { capture_callback_invoke(capture_cb_capture_fixed_finished, cap_session); } } g_free(capture_opts->save_file); is_tempfile = FALSE; cf_set_tempfile((capture_file *)cap_session->cf, FALSE); } else { /* we didn't have a save_file before; must be a tempfile */ is_tempfile = TRUE; cf_set_tempfile((capture_file *)cap_session->cf, TRUE); } /* save the new filename */ capture_opts->save_file = g_strdup(new_file); /* if we are in real-time mode, open the new file now */ if(capture_opts->real_time_mode) { /* Attempt to open the capture file and set up to read from it. */ switch(cf_open((capture_file *)cap_session->cf, capture_opts->save_file, WTAP_TYPE_AUTO, is_tempfile, &err)) { case CF_OK: break; case CF_ERROR: /* Don't unlink (delete) the save file - leave it around, for debugging purposes. */ g_free(capture_opts->save_file); capture_opts->save_file = NULL; return FALSE; } } else { capture_callback_invoke(capture_cb_capture_prepared, cap_session); } if(capture_opts->show_info) { if (cap_session->wtap != NULL) { wtap_close(cap_session->wtap); } cap_session->wtap = wtap_open_offline(new_file, WTAP_TYPE_AUTO, &err, &err_info, FALSE); if (!cap_session->wtap) { err_msg = g_strdup_printf(cf_open_error_message(err, err_info, FALSE, WTAP_FILE_TYPE_SUBTYPE_UNKNOWN), new_file); g_warning("capture_input_new_file: %d (%s)", err, err_msg); g_free(err_msg); return FALSE; } } if(capture_opts->real_time_mode) { capture_callback_invoke(capture_cb_capture_update_started, cap_session); } else { capture_callback_invoke(capture_cb_capture_fixed_started, cap_session); } cap_session->state = CAPTURE_RUNNING; return TRUE; } static void capture_info_packet(info_data_t* cap_info, gint wtap_linktype, const guchar *pd, guint32 caplen, union wtap_pseudo_header *pseudo_header) { capture_packet_info_t cpinfo; /* Setup the capture packet structure */ cpinfo.counts = cap_info->counts.counts_hash; cap_info->counts.total++; if (!try_capture_dissector("wtap_encap", wtap_linktype, pd, 0, caplen, &cpinfo, pseudo_header)) cap_info->counts.other++; } /* new packets arrived */ static void capture_info_new_packets(int to_read, wtap *wth, info_data_t* cap_info) { int err; gchar *err_info; gint64 data_offset; wtap_rec rec; Buffer buf; union wtap_pseudo_header *pseudo_header; int wtap_linktype; cap_info->ui.new_packets = to_read; /*g_warning("new packets: %u", to_read);*/ wtap_rec_init(&rec); ws_buffer_init(&buf, 1514); while (to_read > 0) { wtap_cleareof(wth); if (wtap_read(wth, &rec, &buf, &err, &err_info, &data_offset)) { if (rec.rec_type == REC_TYPE_PACKET) { pseudo_header = &rec.rec_header.packet_header.pseudo_header; wtap_linktype = rec.rec_header.packet_header.pkt_encap; capture_info_packet(cap_info, wtap_linktype, ws_buffer_start_ptr(&buf), rec.rec_header.packet_header.caplen, pseudo_header); /*g_warning("new packet");*/ to_read--; } } } wtap_rec_cleanup(&rec); ws_buffer_free(&buf); capture_info_ui_update(&cap_info->ui); } /* capture child tells us we have new packets to read */ void capture_input_new_packets(capture_session *cap_session, int to_read) { capture_options *capture_opts = cap_session->capture_opts; int err; g_assert(capture_opts->save_file); if(capture_opts->real_time_mode) { /* Read from the capture file the number of records the child told us it added. */ switch (cf_continue_tail((capture_file *)cap_session->cf, to_read, &cap_session->rec, &cap_session->buf, &err)) { case CF_READ_OK: case CF_READ_ERROR: /* Just because we got an error, that doesn't mean we were unable to read any of the file; we handle what we could get from the file. XXX - abort on a read error? */ capture_callback_invoke(capture_cb_capture_update_continue, cap_session); break; case CF_READ_ABORTED: /* Kill the child capture process; the user wants to exit, and we shouldn't just leave it running. */ capture_kill_child(cap_session); break; } } else { cf_fake_continue_tail((capture_file *)cap_session->cf); capture_callback_invoke(capture_cb_capture_fixed_continue, cap_session); } if(capture_opts->show_info) capture_info_new_packets(to_read, cap_session->wtap, cap_session->cap_data_info); } /* Capture child told us how many dropped packets it counted. */ void capture_input_drops(capture_session *cap_session, guint32 dropped, const char* interface_name) { if (interface_name != NULL) { g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_INFO, "%u packet%s dropped from %s", dropped, plurality(dropped, "", "s"), interface_name); } else { g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_INFO, "%u packet%s dropped", dropped, plurality(dropped, "", "s")); } g_assert(cap_session->state == CAPTURE_RUNNING); cf_set_drops_known((capture_file *)cap_session->cf, TRUE); cf_set_drops((capture_file *)cap_session->cf, dropped); } /* Capture child told us that an error has occurred while starting/running the capture. The buffer we're handed has *two* null-terminated strings in it - a primary message and a secondary message, one right after the other. The secondary message might be a null string. */ void capture_input_error_message(capture_session *cap_session, char *error_msg, char *secondary_error_msg) { gchar *safe_error_msg; gchar *safe_secondary_error_msg; g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Error message from child: \"%s\", \"%s\"", error_msg, secondary_error_msg); g_assert(cap_session->state == CAPTURE_PREPARING || cap_session->state == CAPTURE_RUNNING); safe_error_msg = simple_dialog_format_message(error_msg); if (*secondary_error_msg != '\0') { /* We have both primary and secondary messages. */ safe_secondary_error_msg = simple_dialog_format_message(secondary_error_msg); simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "%s%s%s\n\n%s", simple_dialog_primary_start(), safe_error_msg, simple_dialog_primary_end(), safe_secondary_error_msg); g_free(safe_secondary_error_msg); } else { /* We have only a primary message. */ simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "%s%s%s", simple_dialog_primary_start(), safe_error_msg, simple_dialog_primary_end()); } g_free(safe_error_msg); /* the capture child will close the sync_pipe if required, nothing to do for now */ } /* Capture child told us that an error has occurred while parsing a capture filter when starting/running the capture. */ void capture_input_cfilter_error_message(capture_session *cap_session, guint i, const char *error_message) { capture_options *capture_opts = cap_session->capture_opts; dfilter_t *rfcode = NULL; gchar *safe_cfilter; gchar *safe_descr; gchar *safe_cfilter_error_msg; interface_options *interface_opts; g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture filter error message from child: \"%s\"", error_message); g_assert(cap_session->state == CAPTURE_PREPARING || cap_session->state == CAPTURE_RUNNING); g_assert(i < capture_opts->ifaces->len); interface_opts = &g_array_index(capture_opts->ifaces, interface_options, i); safe_cfilter = simple_dialog_format_message(interface_opts->cfilter); safe_descr = simple_dialog_format_message(interface_opts->descr); safe_cfilter_error_msg = simple_dialog_format_message(error_message); /* Did the user try a display filter? */ if (dfilter_compile(interface_opts->cfilter, &rfcode, NULL) && rfcode != NULL) { simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "%sInvalid capture filter \"%s\" for interface %s.%s\n" "\n" "That string looks like a valid display filter; however, it isn't a valid\n" "capture filter (%s).\n" "\n" "Note that display filters and capture filters don't have the same syntax,\n" "so you can't use most display filter expressions as capture filters.\n" "\n" "See the User's Guide for a description of the capture filter syntax.", simple_dialog_primary_start(), safe_cfilter, safe_descr, simple_dialog_primary_end(), safe_cfilter_error_msg); dfilter_free(rfcode); } else { simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "%sInvalid capture filter \"%s\" for interface %s.%s\n" "\n" "That string isn't a valid capture filter (%s).\n" "See the User's Guide for a description of the capture filter syntax.", simple_dialog_primary_start(), safe_cfilter, safe_descr, simple_dialog_primary_end(), safe_cfilter_error_msg); } g_free(safe_cfilter_error_msg); g_free(safe_descr); g_free(safe_cfilter); /* the capture child will close the sync_pipe if required, nothing to do for now */ } /* capture child closed its side of the pipe, do the required cleanup */ void capture_input_closed(capture_session *cap_session, gchar *msg) { capture_options *capture_opts = cap_session->capture_opts; int err; g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture stopped."); g_assert(cap_session->state == CAPTURE_PREPARING || cap_session->state == CAPTURE_RUNNING); if (msg != NULL) simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "%s", msg); wtap_rec_cleanup(&cap_session->rec); ws_buffer_free(&cap_session->buf); if(cap_session->state == CAPTURE_PREPARING) { /* We started the capture child, but we didn't manage to start the capture process; note that the attempt to start it failed. */ capture_callback_invoke(capture_cb_capture_failed, cap_session); } else { /* We started a capture; process what's left of the capture file if we were in "update list of packets in real time" mode, or process all of it if we weren't. */ if(capture_opts->real_time_mode) { cf_read_status_t status; /* Read what remains of the capture file. */ status = cf_finish_tail((capture_file *)cap_session->cf, &cap_session->rec, &cap_session->buf, &err); /* Tell the GUI we are not doing a capture any more. Must be done after the cf_finish_tail(), so file lengths are correctly displayed */ cap_session->session_will_restart = FALSE; capture_callback_invoke(capture_cb_capture_update_finished, cap_session); /* Finish the capture. */ switch (status) { case CF_READ_OK: if (cap_session->count == 0 && !capture_opts->restart) { simple_dialog(ESD_TYPE_INFO, ESD_BTN_OK, "%sNo packets captured.%s\n" "\n" "As no data was captured, closing the %scapture file.\n" "\n" "\n" "Help about capturing can be found at\n" "\n" " https://wiki.wireshark.org/CaptureSetup" #ifdef _WIN32 "\n\n" "Wireless (Wi-Fi/WLAN):\n" "Try to switch off promiscuous mode in the Capture Options." #endif "", simple_dialog_primary_start(), simple_dialog_primary_end(), cf_is_tempfile((capture_file *)cap_session->cf) ? "temporary " : ""); cf_close((capture_file *)cap_session->cf); } break; case CF_READ_ERROR: /* Just because we got an error, that doesn't mean we were unable to read any of the file; we handle what we could get from the file. */ break; case CF_READ_ABORTED: /* Exit by leaving the main loop, so that any quit functions we registered get called. */ main_window_quit(); break; } } else { /* first of all, we are not doing a capture any more */ capture_callback_invoke(capture_cb_capture_fixed_finished, cap_session); /* this is a normal mode capture and if no error happened, read in the capture file data */ if(capture_opts->save_file != NULL) { capture_input_read_all(cap_session, cf_is_tempfile((capture_file *)cap_session->cf), cf_get_drops_known((capture_file *)cap_session->cf), cf_get_drops((capture_file *)cap_session->cf)); } } } if(capture_opts->show_info) { capture_info_ui_destroy(&cap_session->cap_data_info->ui); if(cap_session->wtap) wtap_close(cap_session->wtap); } cap_session->state = CAPTURE_STOPPED; /* if we couldn't open a capture file, there's nothing more for us to do */ if(capture_opts->save_file == NULL) { cf_close((capture_file *)cap_session->cf); return; } /* does the user wants to restart the current capture? */ if(capture_opts->restart) { capture_opts->restart = FALSE; /* If we have a ring buffer, the original save file has been overwritten with the "ring filename". Restore it before starting again */ if ((capture_opts->multi_files_on) && (capture_opts->orig_save_file != NULL)) { g_free(capture_opts->save_file); capture_opts->save_file = g_strdup(capture_opts->orig_save_file); } /* If it was a tempfile, throw away the old filename (so it will become a tempfile again) */ if (cf_is_tempfile((capture_file *)cap_session->cf)) { g_free(capture_opts->save_file); capture_opts->save_file = NULL; } } else { /* We're not doing a capture any more, so we don't have a save file. */ g_free(capture_opts->save_file); capture_opts->save_file = NULL; } } if_stat_cache_t * capture_stat_start(capture_options *capture_opts) { int stat_fd; ws_process_id fork_child; gchar *msg; if_stat_cache_t *sc = g_new0(if_stat_cache_t, 1); if_stat_cache_item_t *sc_item; guint i; interface_t *device; sc->stat_fd = -1; sc->fork_child = WS_INVALID_PID; /* Fire up dumpcap. */ /* * XXX - on systems with BPF, the number of BPF devices limits the * number of devices on which you can capture simultaneously. * * This means that * * 1) this might fail if you run out of BPF devices * * and * * 2) opening every interface could leave too few BPF devices * for *other* programs. * * It also means the system could end up getting a lot of traffic * that it has to pass through the networking stack and capture * mechanism, so opening all the devices and presenting packet * counts might not always be a good idea. */ if (sync_interface_stats_open(&stat_fd, &fork_child, &msg, NULL) == 0) { sc->stat_fd = stat_fd; sc->fork_child = fork_child; /* Initialize the cache */ for (i = 0; i < capture_opts->all_ifaces->len; i++) { device = &g_array_index(capture_opts->all_ifaces, interface_t, i); if (device->type != IF_PIPE) { sc_item = (if_stat_cache_item_t *)g_malloc0(sizeof(if_stat_cache_item_t)); g_assert(device->if_info.name); sc_item->name = g_strdup(device->if_info.name); sc->cache_list = g_list_prepend(sc->cache_list, sc_item); } } } else { g_free(msg); /* XXX: should we display this to the user ? */ } return sc; } #define MAX_STAT_LINE_LEN 500 static void capture_stat_cache_update(if_stat_cache_t *sc) { gchar stat_line[MAX_STAT_LINE_LEN] = ""; gchar **stat_parts; GList *sc_entry; if_stat_cache_item_t *sc_item; if (!sc || sc->fork_child == WS_INVALID_PID) { return; } while (sync_pipe_gets_nonblock(sc->stat_fd, stat_line, MAX_STAT_LINE_LEN) > 0) { g_strstrip(stat_line); stat_parts = g_strsplit(stat_line, "\t", 3); if (stat_parts[0] == NULL || stat_parts[1] == NULL || stat_parts[2] == NULL) { g_strfreev(stat_parts); continue; } for (sc_entry = sc->cache_list; sc_entry != NULL; sc_entry = g_list_next(sc_entry)) { sc_item = (if_stat_cache_item_t *)sc_entry->data; if (strcmp(sc_item->name, stat_parts[0]) == 0) { sc_item->ps.ps_recv = (u_int) strtoul(stat_parts[1], NULL, 10); sc_item->ps.ps_drop = (u_int) strtoul(stat_parts[2], NULL, 10); } } g_strfreev(stat_parts); } } gboolean capture_stats(if_stat_cache_t *sc, char *ifname, struct pcap_stat *ps) { GList *sc_entry; if_stat_cache_item_t *sc_item; if (!sc || sc->fork_child == WS_INVALID_PID || !ifname || !ps) { return FALSE; } capture_stat_cache_update(sc); for (sc_entry = sc->cache_list; sc_entry != NULL; sc_entry = g_list_next(sc_entry)) { sc_item = (if_stat_cache_item_t *)sc_entry->data; if (strcmp(sc_item->name, ifname) == 0) { memcpy(ps, &sc_item->ps, sizeof(struct pcap_stat)); return TRUE; } } return FALSE; } void capture_stat_stop(if_stat_cache_t *sc) { GList *sc_entry; if_stat_cache_item_t *sc_item; int ret; gchar *msg; if (!sc) { return; } if (sc->fork_child != WS_INVALID_PID) { ret = sync_interface_stats_close(&sc->stat_fd, &sc->fork_child, &msg); if (ret == -1) { /* XXX - report failure? */ g_free(msg); } } for (sc_entry = sc->cache_list; sc_entry != NULL; sc_entry = g_list_next(sc_entry)) { sc_item = (if_stat_cache_item_t *)sc_entry->data; g_free(sc_item->name); g_free(sc_item); } g_list_free(sc->cache_list); g_free(sc); } #endif /* HAVE_LIBPCAP */ /* * Editor modelines - https://www.wireshark.org/tools/modelines.html * * Local Variables: * c-basic-offset: 4 * tab-width: 8 * indent-tabs-mode: nil * End: * * ex: set shiftwidth=4 tabstop=8 expandtab: * :indentSize=4:tabSize=8:noTabs=true: */