/* tap-icmpstat.c * icmpstat 2011 Christopher Maynard * * $Id$ * * Wireshark - Network traffic analyzer * By Gerald Combs * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* This module provides icmp echo request/reply SRT statistics to tshark. * It is only used by tshark and not wireshark * * It was based on tap-rpcstat.c and doc/README.tapping. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #ifdef HAVE_SYS_TYPES_H # include #endif #include #include "epan/packet_info.h" #include #include #include #include /* used to keep track of the ICMP statistics */ typedef struct _icmpstat_t { char *filter; GSList *rt_list; guint num_rqsts; guint num_resps; double min_msecs; double max_msecs; double tot_msecs; } icmpstat_t; /* This callback is never used by tshark but it is here for completeness. When * registering below, we could just have left this function as NULL. * * When used by wireshark, this function will be called whenever we would need * to reset all state, such as when wireshark opens a new file, when it starts * a new capture, when it rescans the packetlist after some prefs have changed, * etc. * * So if your application has some state it needs to clean up in those * situations, here is a good place to put that code. */ static void icmpstat_reset(void *tapdata) { icmpstat_t *icmpstat = tapdata; g_slist_free(icmpstat->rt_list); icmpstat->rt_list = NULL; icmpstat->num_rqsts = 0; icmpstat->num_resps = 0; icmpstat->min_msecs = 1.0 * G_MAXUINT; icmpstat->max_msecs = 0.0; icmpstat->tot_msecs = 0.0; } /* This callback is invoked whenever the tap system has seen a packet we might * be interested in. The function is to be used to only update internal state * information in the *tapdata structure, and if there were state changes which * requires the window to be redrawn, return 1 and (*draw) will be called * sometime later. * * This function should be as lightweight as possible since it executes * together with the normal wireshark dissectors. Try to push as much * processing as possible into (*draw) instead since that function executes * asynchronously and does not affect the main thread's performance. * * If it is possible, try to do all "filtering" explicitly since you will get * MUCH better performance than applying a similar display-filter in the * register call. * * The third parameter is tap dependent. Since we register this one to the * "icmp" tap, the third parameter type is icmp_transaction_t. * * function returns : * 0: no updates, no need to call (*draw) later * !0: state has changed, call (*draw) sometime later */ static int icmpstat_packet(void *tapdata, packet_info *pinfo, epan_dissect_t *edt _U_, const void *data) { icmpstat_t *icmpstat = tapdata; const icmp_transaction_t *trans = data; double *rt; if (trans == NULL) return 0; if (trans->resp_frame) { rt = g_malloc(sizeof(double)); if (rt == NULL) return 0; *rt = trans->resp_time; icmpstat->rt_list = g_slist_prepend(icmpstat->rt_list, rt); icmpstat->num_resps++; if (icmpstat->min_msecs > trans->resp_time) icmpstat->min_msecs = trans->resp_time; if (icmpstat->max_msecs < trans->resp_time) icmpstat->max_msecs = trans->resp_time; icmpstat->tot_msecs += trans->resp_time; } else if (trans->rqst_frame) icmpstat->num_rqsts++; else return 0; return 1; } static double compute_sdev(double average, guint num, GSList *slist) { double diff; double sq_diff_sum; if (num == 0) return 0.0; for ( sq_diff_sum = 0.0; slist; slist = g_slist_next(slist)) { diff = *(double *)slist->data - average; sq_diff_sum += diff * diff; } return sqrt(sq_diff_sum / num); } /* This callback is used when tshark wants us to draw/update our data to the * output device. Since this is tshark, the only output is stdout. * TShark will only call this callback once, which is when tshark has finished * reading all packets and exits. * If used with wireshark this may be called any time, perhaps once every 3 * seconds or so. * This function may even be called in parallel with (*reset) or (*draw), so * make sure there are no races. The data in the icmpstat_t can thus change * beneath us. Beware! * * How best to display the data? For now, following other tap statistics * output, but here are a few other alternatives we might choose from: * * -> Windows ping output: * Ping statistics for : * Packets: Sent = , Received = , Lost = (% loss), * Approximate round trip times in milli-seconds: * Minimum = ms, Maximum = ms, Average = ms * * -> Cygwin ping output: * ---- PING Statistics---- * packets transmitted, packets received, % packet loss * round-trip (ms) min/avg/max/med = /// * * -> Linux ping output: * --- ping statistics --- * packets transmitted, received, % packet loss, time ms * rtt min/avg/max/mdev = /// ms */ static void icmpstat_draw(void *tapdata) { icmpstat_t *icmpstat = tapdata; unsigned int lost; double average, sdev; printf("\n"); printf("==========================================================================\n"); printf("ICMP SRT Statistics (all times in ms):\n"); printf("Filter: %s\n", icmpstat->filter ? icmpstat->filter : ""); printf("Requests Replies Lost %% Loss Min SRT Max SRT Avg SRT SDEV\n"); if (icmpstat->num_rqsts) { lost = icmpstat->num_rqsts - icmpstat->num_resps; average = icmpstat->tot_msecs / icmpstat->num_resps; sdev = compute_sdev(average, icmpstat->num_resps, icmpstat->rt_list); printf("%-10u%-10u%-10u%5.1f%% %-10.3f%-10.3f%-10.3f%-10.3f\n", icmpstat->num_rqsts, icmpstat->num_resps, lost, 100.0 * lost / icmpstat->num_rqsts, icmpstat->min_msecs >= G_MAXUINT ? 0.0 : icmpstat->min_msecs, icmpstat->max_msecs, average, sdev); } else printf("0 0 0 0.0%% 0.000 0.000 0.000 0.000\n"); printf("==========================================================================\n"); } /* When called, this function will create a new instance of icmpstat. * * This function is called from tshark when it parses the -z icmp, arguments * and it creates a new instance to store statistics in and registers this new * instance for the icmp tap. */ static void icmpstat_init(const char *optarg, void* userdata _U_) { icmpstat_t *icmpstat; const char *filter = NULL; GString *error_string; if (strstr(optarg, "icmp,srt,")) filter = optarg + strlen("icmp,srt,"); icmpstat = g_malloc0(sizeof(icmpstat_t)); icmpstat->min_msecs = 1.0 * G_MAXUINT; if (icmpstat == NULL) { fprintf(stderr, "tshark: g_malloc() fatal error.\n"); exit(1); } if (filter) icmpstat->filter = g_strdup(filter); /* It is possible to create a filter and attach it to the callbacks. Then the * callbacks would only be invoked if the filter matched. * * Evaluating filters is expensive and if we can avoid it and not use them, * then we gain performance. * * In this case we do the filtering for protocol and version inside the * callback itself but use whatever filter the user provided. */ error_string = register_tap_listener("icmp", icmpstat, icmpstat->filter, TL_REQUIRES_NOTHING, icmpstat_reset, icmpstat_packet, icmpstat_draw); if (error_string) { /* error, we failed to attach to the tap. clean up */ if (icmpstat->filter) g_free(icmpstat->filter); g_free(icmpstat); fprintf(stderr, "tshark: Couldn't register icmp,srt tap: %s\n", error_string->str); g_string_free(error_string, TRUE); exit(1); } } void register_tap_listener_icmpstat(void) { register_stat_cmd_arg("icmp,srt", icmpstat_init, NULL); }