unix4lyfe git - darkstat/blob - darkstat.c

   1 /* darkstat 3
   2  * copyright (c) 2001-2011 Emil Mikulic.
   3  *
   4  * darkstat.c: signals, cmdline parsing, program body.
   5  *
   6  * You may use, modify and redistribute this file under the terms of the
   7  * GNU General Public License version 2. (see COPYING.GPL)
   8  */
   9
  10 #include "acct.h"
  11 #include "cap.h"
  12 #include "cdefs.h"
  13 #include "config.h"
  14 #include "conv.h"
  15 #include "daylog.h"
  16 #include "db.h"
  17 #include "dns.h"
  18 #include "err.h"
  19 #include "http.h"
  20 #include "hosts_db.h"
  21 #include "localip.h"
  22 #include "ncache.h"
  23 #include "pidfile.h"
  24
  25 #include <assert.h>
  26 #include <errno.h>
  27 #include <inttypes.h>
  28 #include <signal.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <syslog.h>
  33 #include <unistd.h>
  34 #include <pcap.h>
  35
  36 #include "now.h"
  37 time_t now;
  38
  39 #ifndef INADDR_NONE
  40 # define INADDR_NONE (-1) /* Solaris */
  41 #endif
  42
  43 /* --- Signal handling --- */
  44 static volatile int running = 1;
  45 static void sig_shutdown(int signum _unused_) { running = 0; }
  46
  47 static volatile int reset_pending = 0, export_pending = 0;
  48 static void sig_reset(int signum _unused_)
  49 {
  50    reset_pending = 1;
  51    export_pending = 1;
  52 }
  53
  54 static void sig_export(int signum _unused_) { export_pending = 1; }
  55
  56 /* --- Commandline parsing --- */
  57 static unsigned long
  58 parsenum(const char *str, unsigned long max /* 0 for no max */)
  59 {
  60    unsigned long n;
  61    char *end;
  62
  63    errno = 0;
  64    n = strtoul(str, &end, 10);
  65    if (*end != '\0')
  66       errx(1, "\"%s\" is not a valid number", str);
  67    if (errno == ERANGE)
  68       errx(1, "\"%s\" is out of range", str);
  69    if ((max != 0) && (n > max))
  70       errx(1, "\"%s\" is out of range (max %lu)", str, max);
  71    return n;
  72 }
  73
  74 const char *opt_interface = NULL;
  75 static void cb_interface(const char *arg) { opt_interface = arg; }
  76
  77 const char *opt_capfile = NULL;
  78 static void cb_capfile(const char *arg) { opt_capfile = arg; }
  79
  80 int opt_want_snaplen = -1;
  81 static void cb_snaplen(const char *arg)
  82 { opt_want_snaplen = (int)parsenum(arg, 0); }
  83
  84 int opt_want_pppoe = 0;
  85 static void cb_pppoe(const char *arg _unused_) { opt_want_pppoe = 1; }
  86
  87 int opt_want_syslog = 0;
  88 static void cb_syslog(const char *arg _unused_) { opt_want_syslog = 1; }
  89
  90 int opt_want_verbose = 0;
  91 static void cb_verbose(const char *arg _unused_) { opt_want_verbose = 1; }
  92
  93 int opt_want_daemonize = 1;
  94 static void cb_no_daemon(const char *arg _unused_) { opt_want_daemonize = 0; }
  95
  96 int opt_want_promisc = 1;
  97 static void cb_no_promisc(const char *arg _unused_) { opt_want_promisc = 0; }
  98
  99 int opt_want_dns = 1;
 100 static void cb_no_dns(const char *arg _unused_) { opt_want_dns = 0; }
 101
 102 int opt_want_macs = 1;
 103 static void cb_no_macs(const char *arg _unused_) { opt_want_macs = 0; }
 104
 105 int opt_want_lastseen = 1;
 106 static void cb_no_lastseen(const char *arg _unused_) { opt_want_lastseen = 0; }
 107
 108 unsigned short opt_bindport = 667;
 109 static void cb_port(const char *arg)
 110 { opt_bindport = (unsigned short)parsenum(arg, 65536); }
 111
 112 static void cb_bindaddr(const char *arg) { http_add_bindaddr(arg); }
 113
 114 const char *opt_filter = NULL;
 115 static void cb_filter(const char *arg) { opt_filter = arg; }
 116
 117 static void cb_local(const char *arg) { acct_init_localnet(arg); }
 118
 119 const char *opt_chroot_dir = NULL;
 120 static void cb_chroot(const char *arg) { opt_chroot_dir = arg; }
 121
 122 const char *opt_privdrop_user = NULL;
 123 static void cb_user(const char *arg) { opt_privdrop_user = arg; }
 124
 125 const char *daylog_fn = NULL;
 126 static void cb_daylog(const char *arg)
 127 {
 128    if (opt_chroot_dir == NULL)
 129       errx(1, "the daylog file is relative to the chroot.\n"
 130       "You must specify a --chroot dir before you can use --daylog.");
 131    else
 132       daylog_fn = arg;
 133 }
 134
 135 const char *import_fn = NULL;
 136 static void cb_import(const char *arg)
 137 {
 138    if (opt_chroot_dir == NULL)
 139       errx(1, "the import file is relative to the chroot.\n"
 140       "You must specify a --chroot dir before you can use --import.");
 141    else
 142       import_fn = arg;
 143 }
 144
 145 const char *export_fn = NULL;
 146 static void cb_export(const char *arg)
 147 {
 148    if ((opt_chroot_dir == NULL) && (opt_capfile == NULL))
 149       errx(1, "the export file is relative to the chroot.\n"
 150       "You must specify a --chroot dir before you can use --export.");
 151    else
 152       export_fn = arg;
 153 }
 154
 155 static const char *pid_fn = NULL;
 156 static void cb_pidfile(const char *arg)
 157 {
 158    if (opt_chroot_dir == NULL)
 159       errx(1, "the pidfile is relative to the chroot.\n"
 160       "You must specify a --chroot dir before you can use --pidfile.");
 161    else
 162       pid_fn = arg;
 163 }
 164
 165 unsigned int opt_hosts_max = 1000;
 166 static void cb_hosts_max(const char *arg)
 167 { opt_hosts_max = parsenum(arg, 0); }
 168
 169 unsigned int opt_hosts_keep = 500;
 170 static void cb_hosts_keep(const char *arg)
 171 { opt_hosts_keep = parsenum(arg, 0); }
 172
 173 unsigned int opt_ports_max = 200;
 174 static void cb_ports_max(const char *arg)
 175 { opt_ports_max = parsenum(arg, 65536); }
 176
 177 unsigned int opt_ports_keep = 30;
 178 static void cb_ports_keep(const char *arg)
 179 { opt_ports_keep = parsenum(arg, 65536); }
 180
 181 unsigned int opt_highest_port = 65535;
 182 static void cb_highest_port(const char *arg)
 183 { opt_highest_port = parsenum(arg, 65535); }
 184
 185 int opt_wait_secs = -1;
 186 static void cb_wait_secs(const char *arg)
 187 { opt_wait_secs = (int)parsenum(arg, 0); }
 188
 189 int opt_want_hexdump = 0;
 190 static void cb_hexdump(const char *arg _unused_) { opt_want_hexdump = 1; }
 191
 192 /* --- */
 193
 194 struct cmdline_arg {
 195    const char *name, *arg_name; /* NULL arg_name means unary */
 196    void (*callback)(const char *arg);
 197    int num_seen;
 198 };
 199
 200 static struct cmdline_arg cmdline_args[] = {
 201    {"-i",             "interface",       cb_interface,    0},
 202    {"-r",             "file",            cb_capfile,      0},
 203    {"--snaplen",      "bytes",           cb_snaplen,      0},
 204    {"--pppoe",        NULL,              cb_pppoe,        0},
 205    {"--syslog",       NULL,              cb_syslog,       0},
 206    {"--verbose",      NULL,              cb_verbose,      0},
 207    {"--no-daemon",    NULL,              cb_no_daemon,    0},
 208    {"--no-promisc",   NULL,              cb_no_promisc,   0},
 209    {"--no-dns",       NULL,              cb_no_dns,       0},
 210    {"--no-macs",      NULL,              cb_no_macs,      0},
 211    {"--no-lastseen",  NULL,              cb_no_lastseen,  0},
 212    {"-p",             "port",            cb_port,         0},
 213    {"-b",             "bindaddr",        cb_bindaddr,     -1},
 214    {"-f",             "filter",          cb_filter,       0},
 215    {"-l",             "network/netmask", cb_local,        0},
 216    {"--chroot",       "dir",             cb_chroot,       0},
 217    {"--user",         "username",        cb_user,         0},
 218    {"--daylog",       "filename",        cb_daylog,       0},
 219    {"--import",       "filename",        cb_import,       0},
 220    {"--export",       "filename",        cb_export,       0},
 221    {"--pidfile",      "filename",        cb_pidfile,      0},
 222    {"--hosts-max",    "count",           cb_hosts_max,    0},
 223    {"--hosts-keep",   "count",           cb_hosts_keep,   0},
 224    {"--ports-max",    "count",           cb_ports_max,    0},
 225    {"--ports-keep",   "count",           cb_ports_keep,   0},
 226    {"--highest-port", "port",            cb_highest_port, 0},
 227    {"--wait",         "secs",            cb_wait_secs,    0},
 228    {"--hexdump",      NULL,              cb_hexdump,      0},
 229    {NULL,             NULL,              NULL,            0}
 230 };
 231
 232 static void
 233 pad(const int width)
 234 {
 235    int i;
 236    for (i=0; i<width; i++) printf(" ");
 237 }
 238
 239 /*
 240  * We autogenerate the usage statement from the cmdline_args data structure.
 241  */
 242 static void
 243 usage(void)
 244 {
 245    int width, first;
 246    struct cmdline_arg *arg;
 247
 248    printf(PACKAGE_STRING " (built with libpcap %d.%d)\n\n",
 249       PCAP_VERSION_MAJOR, PCAP_VERSION_MINOR);
 250
 251    width = printf("usage: darkstat ");
 252    first = 1;
 253
 254    for (arg = cmdline_args; arg->name != NULL; arg++) {
 255       if (first) first = 0; else pad(width);
 256       printf("[ %s", arg->name);
 257       if (arg->arg_name != NULL) printf(" %s", arg->arg_name);
 258       printf(" ]\n");
 259    }
 260    printf("\n"
 261 "Please refer to the darkstat(8) manual page for further\n"
 262 "documentation and usage examples.\n");
 263 }
 264
 265 static void
 266 parse_sub_cmdline(const int argc, char * const *argv)
 267 {
 268    struct cmdline_arg *arg;
 269
 270    if (argc == 0) return;
 271    for (arg = cmdline_args; arg->name != NULL; arg++)
 272       if (strcmp(argv[0], arg->name) == 0) {
 273          if ((arg->arg_name != NULL) && (argc == 1)) {
 274             fprintf(stderr,
 275                "error: argument \"%s\" requires parameter \"%s\"\n",
 276                arg->name, arg->arg_name);
 277             usage();
 278             exit(EXIT_FAILURE);
 279          }
 280          if (arg->num_seen > 0) {
 281             fprintf(stderr,
 282                "error: already specified argument \"%s\"\n",
 283                arg->name);
 284             usage();
 285             exit(EXIT_FAILURE);
 286          }
 287
 288          if (arg->num_seen != -1) /* accept more than one */
 289             arg->num_seen++;
 290
 291          if (arg->arg_name == NULL) {
 292             arg->callback(NULL);
 293             parse_sub_cmdline(argc-1, argv+1);
 294          } else {
 295             arg->callback(argv[1]);
 296             parse_sub_cmdline(argc-2, argv+2);
 297          }
 298          return;
 299       }
 300
 301    fprintf(stderr, "error: illegal argument: \"%s\"\n", argv[0]);
 302    usage();
 303    exit(EXIT_FAILURE);
 304 }
 305
 306 static void
 307 parse_cmdline(const int argc, char * const *argv)
 308 {
 309    if (argc < 1) {
 310       /* Not enough args. */
 311       usage();
 312       exit(EXIT_FAILURE);
 313    }
 314
 315    parse_sub_cmdline(argc, argv);
 316
 317    /* start syslogging as early as possible */
 318    if (opt_want_syslog) openlog("darkstat", LOG_NDELAY | LOG_PID, LOG_DAEMON);
 319
 320    /* some default values */
 321    if (opt_chroot_dir == NULL) opt_chroot_dir = CHROOT_DIR;
 322    if (opt_privdrop_user == NULL) opt_privdrop_user = PRIVDROP_USER;
 323
 324    /* sanity check args */
 325    if ((opt_interface == NULL) && (opt_capfile == NULL))
 326       errx(1, "must specify either interface (-i) or capture file (-r)");
 327
 328    if ((opt_interface != NULL) && (opt_capfile != NULL))
 329       errx(1, "can't specify both interface (-i) and capture file (-r)");
 330
 331    if ((opt_hosts_max != 0) && (opt_hosts_keep >= opt_hosts_max)) {
 332       opt_hosts_keep = opt_hosts_max / 2;
 333       warnx("reducing --hosts-keep to %u, to be under --hosts-max (%u)",
 334          opt_hosts_keep, opt_hosts_max);
 335    }
 336    verbosef("max %u hosts, cutting down to %u when exceeded",
 337       opt_hosts_max, opt_hosts_keep);
 338
 339    if ((opt_ports_max != 0) && (opt_ports_keep >= opt_ports_max)) {
 340       opt_ports_keep = opt_ports_max / 2;
 341       warnx("reducing --ports-keep to %u, to be under --ports-max (%u)",
 342          opt_ports_keep, opt_ports_max);
 343    }
 344    verbosef("max %u ports per host, cutting down to %u when exceeded",
 345       opt_ports_max, opt_ports_keep);
 346
 347    if (opt_want_hexdump && !opt_want_verbose) {
 348       opt_want_verbose = 1;
 349       verbosef("--hexdump implies --verbose");
 350    }
 351
 352    if (opt_want_hexdump && opt_want_daemonize) {
 353       opt_want_daemonize = 0;
 354       verbosef("--hexdump implies --no-daemon");
 355    }
 356 }
 357
 358 static void
 359 run_from_capfile(void)
 360 {
 361    graph_init();
 362    hosts_db_init();
 363    cap_from_file(opt_capfile, opt_filter);
 364    cap_stop();
 365    if (export_fn != NULL) db_export(export_fn);
 366    hosts_db_free();
 367    graph_free();
 368 #ifndef PRIu64
 369 #warning "PRIu64 is not defined, using qu instead"
 370 #define PRIu64 "qu"
 371 #endif
 372    verbosef("Total packets: %"PRIu64", bytes: %"PRIu64,
 373       acct_total_packets, acct_total_bytes);
 374 }
 375
 376 /* --- Program body --- */
 377 int
 378 main(int argc, char **argv)
 379 {
 380    test_64order();
 381    parse_cmdline(argc-1, argv+1);
 382
 383    if (opt_capfile) {
 384       /*
 385        * This is very different from a regular run against a network
 386        * interface.
 387        */
 388       run_from_capfile();
 389       return 0;
 390    }
 391
 392    /* must verbosef() before first fork to init lock */
 393    verbosef("starting up");
 394    if (pid_fn) pidfile_create(opt_chroot_dir, pid_fn, opt_privdrop_user);
 395
 396    if (opt_want_daemonize) {
 397       verbosef("daemonizing to run in the background!");
 398       daemonize_start();
 399       verbosef("I am the main process");
 400    }
 401    if (pid_fn) pidfile_write_close();
 402
 403    /* do this first as it forks - minimize memory use */
 404    if (opt_want_dns) dns_init(opt_privdrop_user);
 405    cap_init(opt_interface, opt_filter, opt_want_promisc); /* needs root */
 406    http_listen(opt_bindport);
 407    ncache_init(); /* must do before chroot() */
 408
 409    privdrop(opt_chroot_dir, opt_privdrop_user);
 410
 411    /* Don't need root privs for these: */
 412    now = time(NULL);
 413    if (daylog_fn != NULL) daylog_init(daylog_fn);
 414    graph_init();
 415    hosts_db_init();
 416    if (import_fn != NULL) db_import(import_fn);
 417    localip_init(opt_interface);
 418
 419    if (signal(SIGTERM, sig_shutdown) == SIG_ERR)
 420       errx(1, "signal(SIGTERM) failed");
 421    if (signal(SIGINT, sig_shutdown) == SIG_ERR)
 422       errx(1, "signal(SIGINT) failed");
 423    if (signal(SIGUSR1, sig_reset) == SIG_ERR)
 424       errx(1, "signal(SIGUSR1) failed");
 425    if (signal(SIGUSR2, sig_export) == SIG_ERR)
 426       errx(1, "signal(SIGUSR2) failed");
 427
 428    verbosef("entering main loop");
 429    daemonize_finish();
 430
 431    while (running) {
 432       int select_ret, max_fd = -1, use_timeout = 0;
 433       struct timeval timeout;
 434       fd_set rs, ws;
 435
 436       now = time(NULL);
 437
 438       if (export_pending) {
 439          if (export_fn != NULL)
 440             db_export(export_fn);
 441          export_pending = 0;
 442       }
 443
 444       if (reset_pending) {
 445          hosts_db_reset();
 446          graph_reset();
 447          reset_pending = 0;
 448       }
 449
 450       FD_ZERO(&rs);
 451       FD_ZERO(&ws);
 452
 453       cap_fd_set(&rs, &max_fd, &timeout, &use_timeout);
 454       http_fd_set(&rs, &ws, &max_fd, &timeout, &use_timeout);
 455
 456       select_ret = select(max_fd+1, &rs, &ws, NULL,
 457          (use_timeout) ? &timeout : NULL);
 458
 459       if ((select_ret == 0) && (!use_timeout))
 460             errx(1, "select() erroneously timed out");
 461
 462       if (select_ret == -1) {
 463          if (errno == EINTR)
 464             continue;
 465          else
 466             err(1, "select()");
 467       }
 468       else {
 469          graph_rotate();
 470          cap_poll(&rs);
 471          dns_poll();
 472          http_poll(&rs, &ws);
 473       }
 474    }
 475
 476    verbosef("shutting down");
 477    verbosef("pcap stats: %u packets received, %u packets dropped",
 478       cap_pkts_recv, cap_pkts_drop);
 479    http_stop();
 480    cap_stop();
 481    dns_stop();
 482    if (export_fn != NULL) db_export(export_fn);
 483    hosts_db_free();
 484    graph_free();
 485    if (daylog_fn != NULL) daylog_free();
 486    ncache_free();
 487    if (pid_fn) pidfile_unlink();
 488    verbosef("shut down");
 489    return (EXIT_SUCCESS);
 490 }
 491
 492 /* vim:set ts=3 sw=3 tw=78 expandtab: */