PCAPExporterCfg::PCAPExporterCfg(XMLElement* elem)
    : CfgHelper<PCAPExporterModule, PCAPExporterCfg>(elem, "pcapExporter"), link_type(DLT_EN10MB)
{
    if (!elem) return;

    XMLNode::XMLSet<XMLElement*> set = elem->getElementChildren();
    for (XMLNode::XMLSet<XMLElement*>::iterator it = set.begin();
            it != set.end();
            it++) {
        XMLElement* e = *it;

        if (e->matches("filename")) {
            fileName = e->getFirstText();
        } else if (e->matches("linkType")) {
            int tmp =  pcap_datalink_name_to_val(e->getFirstText().c_str());
            if (tmp == -1) {
                msg(MSG_ERROR, "Found illegal link type");
            } else {
                link_type = tmp;
            }
        } else if (e->matches("snaplen")) {
            snaplen = getInt("snaplen", PCAP_MAX_CAPTURE_LENGTH, e);
        }
    }
}
Ejemplo n.º 2
0
/* Setup filter resources */
static int pf_capture_setup(netio_desc_t *nio,void **opt,
                            int argc,char *argv[])
{
   struct netio_filter_capture *c;
   int link_type;
   
   /* We must have a link type and a filename */
   if (argc != 2)
      return(-1);

   /* Free resources if something has already been done */
   pf_capture_free(nio,opt);

   /* Allocate structure to hold PCAP info */
   if (!(c = malloc(sizeof(*c))))
      return(-1);

   if (pthread_mutex_init(&c->lock,NULL)) {
      fprintf(stderr,"NIO %s: pthread_mutex_init failure (file %s)\n",
              nio->name,argv[0]); 
      goto pcap_lock_err;
   }

   if ((link_type = pcap_datalink_name_to_val(argv[0])) == -1) {
      fprintf(stderr,"NIO %s: unknown link type %s, assuming Ethernet.\n",
              nio->name,argv[0]); 
      link_type = DLT_EN10MB;
   }

   /* Open a dead pcap descriptor */
   if (!(c->desc = pcap_open_dead(link_type,8192))) {
      fprintf(stderr,"NIO %s: pcap_open_dead failure\n",nio->name); 
      goto pcap_open_err;
   }

   /* Open the output file */
   if (!(c->dumper = pcap_dump_open(c->desc,argv[1]))) {
      fprintf(stderr,"NIO %s: pcap_dump_open failure (file %s)\n",
              nio->name,argv[0]); 
      goto pcap_dump_err;
   }

   printf("NIO %s: capturing to file '%s'\n",nio->name,argv[1]);
   *opt = c;
   return(0);

 pcap_dump_err:
   pcap_close(c->desc);
 pcap_open_err:
   pthread_mutex_destroy(&c->lock);
 pcap_lock_err:
   free(c);
   return(-1);
}
Ejemplo n.º 3
0
int
main(int argc, char **argv)
{
	char *cp;
	int op;
	int dflag;
	char *infile;
	int Oflag;
	long snaplen;
	int dlt;
	bpf_u_int32 netmask = PCAP_NETMASK_UNKNOWN;
	char *cmdbuf;
	pcap_t *pd;
	struct bpf_program fcode;

#ifdef WIN32
	if(wsockinit() != 0) return 1;
#endif /* WIN32 */

	dflag = 1;
	infile = NULL;
	Oflag = 1;
	snaplen = 68;
  
	if ((cp = strrchr(argv[0], '/')) != NULL)
		program_name = cp + 1;
	else
		program_name = argv[0];

	opterr = 0;
	while ((op = getopt(argc, argv, "dF:m:Os:")) != -1) {
		switch (op) {

		case 'd':
			++dflag;
			break;

		case 'F':
			infile = optarg;
			break;

		case 'O':
			Oflag = 0;
			break;

		case 'm': {
			in_addr_t addr;

			addr = inet_addr(optarg);
			if (addr == INADDR_NONE)
				error("invalid netmask %s", optarg);
			netmask = addr;
			break;
		}

		case 's': {
			char *end;

			snaplen = strtol(optarg, &end, 0);
			if (optarg == end || *end != '\0'
			    || snaplen < 0 || snaplen > 65535)
				error("invalid snaplen %s", optarg);
			else if (snaplen == 0)
				snaplen = 65535;
			break;
		}

		default:
			usage();
			/* NOTREACHED */
		}
	}

	if (optind >= argc) {
		usage();
		/* NOTREACHED */
	}

	dlt = pcap_datalink_name_to_val(argv[optind]);
	if (dlt < 0)
		error("invalid data link type %s", argv[optind]);
	
	if (infile)
		cmdbuf = read_infile(infile);
	else
		cmdbuf = copy_argv(&argv[optind+1]);

	pd = pcap_open_dead(dlt, snaplen);
	if (pd == NULL)
		error("Can't open fake pcap_t");

	if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
		error("%s", pcap_geterr(pd));
	if (!bpf_validate(fcode.bf_insns, fcode.bf_len))
		warn("Filter doesn't pass validation");
	bpf_dump(&fcode, dflag);
	pcap_close(pd);
	exit(0);
}
Ejemplo n.º 4
0
int
main(int argc, char **argv)
{
	char *cp;
	int op;
#ifndef BDEBUG
	int dflag;
#endif
	char *infile;
	int Oflag;
	long snaplen;
	char *p;
	int dlt;
	int have_fcode = 0;
	bpf_u_int32 netmask = PCAP_NETMASK_UNKNOWN;
	char *cmdbuf;
	pcap_t *pd;
	struct bpf_program fcode;

#ifdef _WIN32
	if (pcap_wsockinit() != 0)
		return 1;
#endif /* _WIN32 */

#ifndef BDEBUG
	dflag = 1;
#else
	/* if optimizer debugging is enabled, output DOT graph
	 * `dflag=4' is equivalent to -dddd to follow -d/-dd/-ddd
	 * convention in tcpdump command line
	 */
	dflag = 4;
#endif
	infile = NULL;
	Oflag = 1;
	snaplen = 68;

	if ((cp = strrchr(argv[0], '/')) != NULL)
		program_name = cp + 1;
	else
		program_name = argv[0];

	opterr = 0;
	while ((op = getopt(argc, argv, "dF:m:Os:")) != -1) {
		switch (op) {

		case 'd':
			++dflag;
			break;

		case 'F':
			infile = optarg;
			break;

		case 'O':
			Oflag = 0;
			break;

		case 'm': {
			bpf_u_int32 addr;

			switch (inet_pton(AF_INET, optarg, &addr)) {

			case 0:                        
				error("invalid netmask %s", optarg);
				break;

			case -1:
				error("invalid netmask %s: %s", optarg,
				    pcap_strerror(errno));
				break;

			case 1:
				netmask = addr;
				break;
			}
			break;
		}

		case 's': {
			char *end;

			snaplen = strtol(optarg, &end, 0);
			if (optarg == end || *end != '\0'
			    || snaplen < 0 || snaplen > 65535)
				error("invalid snaplen %s", optarg);
			else if (snaplen == 0)
				snaplen = 65535;
			break;
		}

		default:
			usage();
			/* NOTREACHED */
		}
	}

	if (optind >= argc) {
		usage();
		/* NOTREACHED */
	}

	dlt = pcap_datalink_name_to_val(argv[optind]);
	if (dlt < 0) {
		dlt = (int)strtol(argv[optind], &p, 10);
		if (p == argv[optind] || *p != '\0')
			error("invalid data link type %s", argv[optind]);
	}

	if (infile)
		cmdbuf = read_infile(infile);
	else
		cmdbuf = copy_argv(&argv[optind+1]);

	pd = pcap_open_dead(dlt, snaplen);
	if (pd == NULL)
		error("Can't open fake pcap_t");

	if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
		error("%s", pcap_geterr(pd));

	have_fcode = 1;
	if (!bpf_validate(fcode.bf_insns, fcode.bf_len))
		warn("Filter doesn't pass validation");

#ifdef BDEBUG
	if (cmdbuf != NULL) {
		// replace line feed with space
		for (cp = cmdbuf; *cp != '\0'; ++cp) {
			if (*cp == '\r' || *cp == '\n') {
				*cp = ' ';
			}
		}
		// only show machine code if BDEBUG defined, since dflag > 3
		printf("machine codes for filter: %s\n", cmdbuf);
	} else
		printf("machine codes for empty filter:\n");
#endif

	bpf_dump(&fcode, dflag);
	free(cmdbuf);
	if (have_fcode)
		pcap_freecode (&fcode);
	pcap_close(pd);
	exit(0);
}
Ejemplo n.º 5
0
int CDECL wine_pcap_datalink_name_to_val(const char *name)
{
    TRACE("(%s)\n", debugstr_a(name));
    return pcap_datalink_name_to_val(name);
}
Ejemplo n.º 6
0
int
main (int argc, char *argv[])
{
	struct pollfd *poll_fd;
	struct config etherpoke_conf;
	struct config_filter *filter_iter;
	struct session_data *pcap_session;
	struct option_data opt;
	char conf_errbuff[CONF_ERRBUF_SIZE];
	char pcap_errbuff[PCAP_ERRBUF_SIZE];
	struct pathname path_config;
	struct sigaction sa;
#ifdef DBG_AVG_LOOP_SPEED
	clock_t clock_start;
	double clock_avg;
#endif
	pid_t pid;
	int i, c, j, rval, syslog_flags, opt_index, filter_cnt, sock, poll_len;
	struct option opt_long[] = {
		{ "", no_argument, NULL, '4' },
		{ "", no_argument, NULL, '6' },
		{ "hostname", required_argument, NULL, 't' },
		{ "daemon", no_argument, NULL, 'd' },
		{ "accept-max", required_argument, NULL, 'm' },
		{ "verbose", no_argument, NULL, 'V' },
		{ "help", no_argument, NULL, 'h' },
		{ "version", no_argument, NULL, 'v' },
		{ NULL, 0, NULL, 0 }
	};

	sock = -1;
	poll_fd = NULL;
	pcap_session = NULL;
	exitno = EXIT_SUCCESS;
	syslog_flags = LOG_PID | LOG_PERROR;
#ifdef DBG_AVG_LOOP_SPEED
	clock_avg = 0;
#endif

	memset (&opt, 0, sizeof (struct option_data));

	opt.accept_max = ACCEPT_MAX;
	opt.ip_version = AF_UNSPEC;

	memset (&path_config, 0, sizeof (struct pathname));
	memset (&etherpoke_conf, 0, sizeof (struct config));

	while ( (c = getopt_long (argc, argv, "46t:dm:Vhv", opt_long, &opt_index)) != -1 ){
		switch ( c ){
			case 'd':
				opt.daemon = 1;
				break;

			case 't':
				rval = hostformat_parse (optarg, opt.hostname, opt.port);

				if ( rval == -1 || strlen (opt.hostname) == 0 || strlen (opt.port) == 0 ){
					fprintf (stderr, "%s: invalid hostname format (expects HOSTNAME:PORT)\n", argv[0]);
					exitno = EXIT_FAILURE;
					goto cleanup;
				}

				opt.tcp_event = 1;
				break;

			case '4':
				opt.ip_version = AF_INET;
				break;

			case '6':
				opt.ip_version = AF_INET6;
				break;

			case 'm':
				rval = sscanf (optarg, "%u", &(opt.accept_max));

				if ( rval < 1 || opt.accept_max == 0 ){
					fprintf (stderr, "%s: invalid number for maximum connections\n", argv[0]);
					exitno = EXIT_FAILURE;
					goto cleanup;
				}
				break;

			case 'V':
				opt.verbose = 1;
				break;

			case 'h':
				etherpoke_help (argv[0]);
				exitno = EXIT_SUCCESS;
				goto cleanup;

			case 'v':
				etherpoke_version (argv[0]);
				exitno = EXIT_SUCCESS;
				goto cleanup;

			default:
				etherpoke_help (argv[0]);
				exitno = EXIT_FAILURE;
				goto cleanup;
		}
	}

	// Check if there are some non-option arguments, these are treated as paths
	// to configuration files.
	if ( (argc - optind) == 0 ){
		fprintf (stderr, "%s: configuration file not specified. Use '--help' to see usage information.\n", argv[0]);
		exitno = EXIT_FAILURE;
		goto cleanup;
	}

	// Change working directory to match the dirname of the config file.
	rval = path_split (argv[optind], &path_config);

	if ( rval != 0 ){
		fprintf (stderr, "%s: cannot split path to configuration file.\n", argv[0]);
		exitno = EXIT_FAILURE;
		goto cleanup;
	}

	rval = chdir (path_config.dir);

	if ( rval == -1 ){
		fprintf (stderr, "%s: cannot set working directory to '%s': %s\n", argv[0], path_config.dir, strerror (errno));
		exitno = EXIT_FAILURE;
		goto cleanup;
	}

	//
	// Load configuration file
	//
	filter_cnt = config_load (&etherpoke_conf, path_config.base, conf_errbuff);

	if ( filter_cnt == -1 ){
		fprintf (stderr, "%s: cannot load configuration file '%s': %s\n", argv[0], argv[optind], conf_errbuff);
		exitno = EXIT_FAILURE;
		goto cleanup;
	} else	if ( filter_cnt == 0 ){
		fprintf (stderr, "%s: nothing to do, no filters defined.\n", argv[0]);
		exitno = EXIT_FAILURE;
		goto cleanup;
	}

	// Allocate enough memory for filters (+1 means that we are also allocating
	// space for listening socket).
	// NOTE: always allocate space for listening socket here, to move this
	// allocation inside the block below (where listening socket is actually
	// allocated) is not a good idea as more complex condition would have to be
	// used inside the main loop.
	poll_len = filter_cnt + 1;

	if ( opt.tcp_event ){
		struct addrinfo *host_addr, addr_hint;
		int opt_val;

		// Increase poll size to accommodate socket descriptors for clients.
		poll_len += opt.accept_max;
		host_addr = NULL;

		memset (&addr_hint, 0, sizeof (struct addrinfo));

		// Setup addrinfo hints
		addr_hint.ai_family = opt.ip_version;
		addr_hint.ai_socktype = SOCK_STREAM;
		addr_hint.ai_flags = AI_PASSIVE | AI_NUMERICSERV;

		rval = getaddrinfo (opt.hostname, opt.port, &addr_hint, &host_addr);

		if ( rval != 0 ){
			fprintf (stderr, "%s: hostname resolve failed: %s\n", argv[0], gai_strerror (rval));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		sock = socket (host_addr->ai_family, host_addr->ai_socktype | SOCK_NONBLOCK, host_addr->ai_protocol);

		if ( sock == -1 ){
			freeaddrinfo (host_addr);
			fprintf (stderr, "%s: cannot create socket: %s\n", argv[0], strerror (errno));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		opt_val = 1;

		if ( setsockopt (sock, SOL_SOCKET, SO_REUSEADDR, &opt_val, sizeof (opt_val)) == -1 ){
			freeaddrinfo (host_addr);
			fprintf (stderr, "%s: cannot set socket options: %s\n", argv[0], strerror (errno));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		rval = bind (sock, (struct sockaddr*) host_addr->ai_addr, host_addr->ai_addrlen);

		if ( rval == -1 ){
			freeaddrinfo (host_addr);
			fprintf (stderr, "%s: cannot bind to address: %s\n", argv[0], strerror (errno));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		rval = listen (sock, LISTEN_QUEUE_LEN);

		if ( rval == -1 ){
			freeaddrinfo (host_addr);
			fprintf (stderr, "%s: %s\n", argv[0], strerror (errno));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		freeaddrinfo (host_addr);
	}

	pcap_session = (struct session_data*) calloc (filter_cnt, sizeof (struct session_data));

	if ( pcap_session == NULL ){
		fprintf (stderr, "%s: cannot allocate memory: %s\n", argv[0], strerror (errno));
		exitno = EXIT_FAILURE;
		goto cleanup;
	}

	for ( i = 0, filter_iter = etherpoke_conf.head; filter_iter != NULL; i++, filter_iter = filter_iter->next ){
		int link_type;

		session_data_init (&(pcap_session[i]));

		pcap_session[i].timeout = filter_iter->session_timeout;
		pcap_session[i].evt_mask = filter_iter->notify;

		pcap_session[i].filter_name = strdup (filter_iter->name);

		if ( pcap_session[i].filter_name == NULL ){
			fprintf (stderr, "%s: cannot allocate memory: %s\n", argv[0], strerror (errno));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		if ( filter_iter->notify & NOTIFY_EXEC ){

			if ( filter_iter->session_begin != NULL ){
				rval = wordexp (filter_iter->session_begin, &(pcap_session[i].evt_cmd_beg), WORDEXP_FLAGS);

				if ( rval != 0 )
					goto filter_error;
			}

			if ( filter_iter->session_error != NULL ){
				rval = wordexp (filter_iter->session_error, &(pcap_session[i].evt_cmd_err), WORDEXP_FLAGS);

				if ( rval != 0 )
					goto filter_error;
			}

			if ( filter_iter->session_end != NULL ){
				rval = wordexp (filter_iter->session_end, &(pcap_session[i].evt_cmd_end), WORDEXP_FLAGS);

				if ( rval != 0 )
					goto filter_error;
			}

filter_error:
			switch ( rval ){
				case WRDE_SYNTAX:
					fprintf (stderr, "%s: invalid event hook in '%s': syntax error\n", argv[0], filter_iter->name);
					exitno = EXIT_FAILURE;
					goto cleanup;

				case WRDE_BADCHAR:
					fprintf (stderr, "%s: invalid event hook in '%s': bad character\n", argv[0], filter_iter->name);
					exitno = EXIT_FAILURE;
					goto cleanup;

				case WRDE_BADVAL:
					fprintf (stderr, "%s: invalid event hook in '%s': referencing undefined variable\n", argv[0], filter_iter->name);
					exitno = EXIT_FAILURE;
					goto cleanup;

				case WRDE_NOSPACE:
					fprintf (stderr, "%s: cannot expand event hook string in '%s': out of memory\n", argv[0], filter_iter->name);
					exitno = EXIT_FAILURE;
					goto cleanup;
			}
		}

		pcap_session[i].handle = pcap_create (filter_iter->interface, pcap_errbuff);

		if ( pcap_session[i].handle == NULL ){
			fprintf (stderr, "%s: cannot start packet capture: %s\n", argv[0], pcap_errbuff);
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		rval = pcap_set_rfmon (pcap_session[i].handle, filter_iter->rfmon);

		if ( rval != 0 ){
			fprintf (stderr, "%s: cannot enable monitor mode on interface '%s': %s\n", argv[0], filter_iter->interface, pcap_geterr (pcap_session[i].handle));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		rval = pcap_set_promisc (pcap_session[i].handle, !(filter_iter->rfmon));

		if ( rval != 0 ){
			fprintf (stderr, "%s: cannot enable promiscuous mode on interface '%s'\n", argv[0], filter_iter->interface);
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		rval = pcap_set_timeout (pcap_session[i].handle, SELECT_TIMEOUT_MS);

		if ( rval != 0 ){
			fprintf (stderr, "%s: cannot set read timeout on interface '%s': %s\n", argv[0], filter_iter->interface, pcap_geterr (pcap_session[i].handle));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		rval = pcap_setnonblock (pcap_session[i].handle, 1, pcap_errbuff);

		if ( rval == -1 ){
			fprintf (stderr, "%s: cannot set nonblock mode on packet capture resource: %s\n", argv[0], pcap_errbuff);
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		rval = pcap_activate (pcap_session[i].handle);

		if ( rval != 0 ){
			fprintf (stderr, "%s: cannot activate packet capture on interface '%s': %s\n", argv[0], filter_iter->interface, pcap_geterr (pcap_session[i].handle));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		// Set link-layer type from configuration file.
		if ( filter_iter->link_type != NULL ){
			link_type = pcap_datalink_name_to_val (filter_iter->link_type);

			if ( link_type == -1 ){
				fprintf (stderr, "%s: cannot convert link-layer type '%s': unknown link-layer type name\n", argv[0], filter_iter->link_type);
				exitno = EXIT_FAILURE;
				goto cleanup;
			}
		} else {
			// If no link-layer type is specified in the configuration file,
			// use default value. At this point I am sticking with DLTs used by
			// wireshark on hardware I have available. Different values may
			// apply to different hardware/driver, therefore more research time
			// should be put into finding 'best' values.
			// More information: http://www.tcpdump.org/linktypes.html
			if ( filter_iter->rfmon ){
				link_type = DLT_IEEE802_11_RADIO;
			} else {
				link_type = DLT_EN10MB;
			}
		}

		rval = pcap_set_datalink (pcap_session[i].handle, link_type);

		if ( rval == -1 ){
			fprintf (stderr, "%s: cannot set data-link type: %s\n", argv[0], pcap_geterr (pcap_session[i].handle));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		if ( filter_iter->match != NULL ){
			struct bpf_program bpf_prog;

			rval = pcap_compile (pcap_session[i].handle, &bpf_prog, filter_iter->match, 0, PCAP_NETMASK_UNKNOWN);

			if ( rval == -1 ){
				fprintf (stderr, "%s: cannot compile the filter '%s' match rule: %s\n", argv[0], filter_iter->name, pcap_geterr (pcap_session[i].handle));
				exitno = EXIT_FAILURE;
				goto cleanup;
			}

			rval = pcap_setfilter (pcap_session[i].handle, &bpf_prog);

			if ( rval == -1 ){
				fprintf (stderr, "%s: cannot apply the filter '%s' on interface '%s': %s\n", argv[0], filter_iter->name, filter_iter->interface, pcap_geterr (pcap_session[i].handle));
				exitno = EXIT_FAILURE;
				goto cleanup;
			}

			pcap_freecode (&bpf_prog);
		}

		pcap_session[i].fd = pcap_get_selectable_fd (pcap_session[i].handle);

		if ( pcap_session[i].fd == -1 ){
			fprintf (stderr, "%s: cannot obtain file descriptor for packet capture interface '%s'\n", argv[0], filter_iter->interface);
			exitno = EXIT_FAILURE;
			goto cleanup;
		}
	}

	// We no longer need data stored in config structure. All neccessary data
	// were moved into session_data structure.
	config_unload (&etherpoke_conf);

	poll_fd = (struct pollfd*) malloc (sizeof (struct pollfd) * poll_len);

	if ( poll_fd == NULL ){
		fprintf (stderr, "%s: cannot allocate memory: %s\n", argv[0], strerror (errno));
		exitno = EXIT_FAILURE;
		goto cleanup;
	}

	// Populate poll structure...
	for ( i = 0; i < poll_len; i++ ){
		// ... with pcap file descriptors...
		if ( i < filter_cnt )
			poll_fd[i].fd = pcap_session[i].fd;
		// ... listening socket...
		else if ( i == filter_cnt )
			poll_fd[i].fd = sock;
		// ... invalid file descriptors (will be ignored by poll(2)), in space reserved for client sockets...
		else
			poll_fd[i].fd = -1;

		poll_fd[i].events = POLLIN | POLLERR;
		poll_fd[i].revents = 0;
	}

	//
	// Setup signal handler
	//
	sa.sa_handler = etherpoke_sigdie;
	sigemptyset (&(sa.sa_mask));
	sa.sa_flags = 0;

	rval = 0;
	rval &= sigaction (SIGINT, &sa, NULL);
	rval &= sigaction (SIGQUIT, &sa, NULL);
	rval &= sigaction (SIGTERM, &sa, NULL);

	sa.sa_handler = SIG_IGN;
	sigemptyset (&(sa.sa_mask));
	sa.sa_flags = 0;

	rval &= sigaction (SIGCHLD, &sa, NULL);

	if ( rval != 0 ){
		fprintf (stderr, "%s: cannot setup signal handler: %s\n", argv[0], strerror (errno));
		exitno = EXIT_FAILURE;
		goto cleanup;
	}

	//
	// Daemonize the process if the flag was set
	//
	if ( opt.daemon == 1 ){
		pid = fork ();

		if ( pid > 0 ){
			exitno = EXIT_SUCCESS;
			goto cleanup;
		} else if ( pid == -1 ){
			fprintf (stderr, "%s: cannot daemonize the process (fork failed).\n", argv[0]);
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		if ( setsid () == -1 ){
			fprintf (stderr, "%s: cannot daemonize the process (setsid failed).\n", argv[0]);
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

		umask (0);

		freopen ("/dev/null", "r", stdin);
		freopen ("/dev/null", "w", stdout);
		freopen ("/dev/null", "w", stderr);
		syslog_flags = LOG_PID;
	}

	openlog ("etherpoke", syslog_flags, LOG_DAEMON);

	syslog (LOG_INFO, "Etherpoke started (loaded filters: %u)", filter_cnt);

	if ( opt.tcp_event )
		syslog (LOG_INFO, "Event notifications available via %s:%s (ACCEPT_MAX: %u)", opt.hostname, opt.port, opt.accept_max);

	//
	// Main loop
	//
	main_loop = 1;

	while ( main_loop ){
		const u_char *pkt_data;
		struct pcap_pkthdr *pkt_header;
		time_t current_time;

		errno = 0;
		rval = poll (poll_fd, poll_len, SELECT_TIMEOUT_MS);

		if ( rval == -1 ){
			if ( errno == EINTR )
				continue;

			syslog (LOG_ERR, "poll(2) failed: %s", strerror (errno));
			exitno = EXIT_FAILURE;
			goto cleanup;
		}

#ifdef DBG_AVG_LOOP_SPEED
		clock_start = clock ();
#endif

		// Accept incoming connection
		if ( poll_fd[filter_cnt].revents & POLLIN ){
			int sock_new;

			sock_new = accept (sock, NULL, NULL);

			if ( sock_new == -1 ){
				syslog (LOG_ERR, "cannot accept new connection: %s", strerror (errno));
				exitno = EXIT_FAILURE;
				goto cleanup;
			}

			// Find unused place in the poll array
			for ( j = (filter_cnt + 1); j < poll_len; j++ ){
				if ( poll_fd[j].fd == -1 ){
					poll_fd[j].fd = sock_new;
					sock_new = -1;
					break;
				}
			}

			if ( sock_new != -1 ){
				if ( opt.verbose )
					syslog (LOG_INFO, "Client refused: too many concurrent connections");
				close (sock_new);
			} else {
				if ( opt.verbose )
					syslog (LOG_INFO, "Client connected...");
			}
		}

		// Take care of incoming client data.  At this point only shutdown and
		// close is handled, no other input is expected from the clients.
		for ( i = (filter_cnt + 1); i < poll_len; i++ ){
			if ( poll_fd[i].revents & POLLIN ){
				char nok[128];

				errno = 0;
				rval = recv (poll_fd[i].fd, nok, sizeof (nok), MSG_DONTWAIT);

				if ( rval <= 0 && (errno != EAGAIN && errno != EWOULDBLOCK) ){
					if ( opt.verbose )
						syslog (LOG_INFO, "Client disconnected...");
					close (poll_fd[i].fd);
					poll_fd[i].fd = -1;
				}
			}
		}

		time (&current_time);

		// Handle changes on pcap file descriptors
		for ( i = 0; i < filter_cnt; i++ ){
			wordexp_t *cmd_exp;
			const char *evt_str;

			// Handle incoming packet
			if ( (poll_fd[i].revents & POLLIN) || (poll_fd[i].revents & POLLERR) ){
				rval = pcap_next_ex (pcap_session[i].handle, &pkt_header, &pkt_data);

				if ( rval == 1 ){
					if ( pcap_session[i].evt.ts == 0 )
						pcap_session[i].evt.type = SE_BEG;

					pcap_session[i].evt.ts = pkt_header->ts.tv_sec;
				} else if ( rval < 0 ){
					pcap_session[i].evt.type = SE_ERR;
				}
			}

			if ( (pcap_session[i].evt.ts > 0)
					&& (difftime (current_time, pcap_session[i].evt.ts) >= pcap_session[i].timeout) ){
				pcap_session[i].evt.type = SE_END;
			}

			switch ( pcap_session[i].evt.type ){
				case SE_NUL:
					// There was no change on this file descriptor, skip to
					// another one. 'continue' may seem a bit confusing here,
					// but it applies to a loop above. Not sure how other
					// compilers will behave (other than gcc).
					continue;

				case SE_BEG:
					evt_str = "BEG";
					cmd_exp = &(pcap_session[i].evt_cmd_beg);
					pcap_session[i].evt.type = SE_NUL;
					break;

				case SE_END:
					cmd_exp = &(pcap_session[i].evt_cmd_end);
					evt_str = "END";
					pcap_session[i].evt.type = SE_NUL;
					pcap_session[i].evt.ts = 0;
					break;

				case SE_ERR:
					evt_str = "ERR";
					cmd_exp = &(pcap_session[i].evt_cmd_err);
					pcap_session[i].evt.type = SE_NUL;
					pcap_session[i].evt.ts = 0;
					break;

				default:
					// Undefined state... What to do, other than die?
					syslog (LOG_ERR, "undefined event type");
					exitno = EXIT_FAILURE;
					goto cleanup;
			}

			if ( opt.verbose )
				syslog (LOG_INFO, "%s:%s", pcap_session[i].filter_name, evt_str);

			// Send socket notification
			if ( pcap_session[i].evt_mask & NOTIFY_SOCK ){
				char msg[CONF_FILTER_NAME_MAXLEN + 5];

				snprintf (msg, sizeof (msg), "%s:%s", pcap_session[i].filter_name, evt_str);

				for ( j = (filter_cnt + 1); j < poll_len; j++ ){
					if ( poll_fd[j].fd == -1 )
						continue;

					errno = 0;
					rval = send (poll_fd[j].fd, msg, strlen (msg) + 1, MSG_NOSIGNAL | MSG_DONTWAIT);

					if ( rval == -1 && (errno != EAGAIN && errno != EWOULDBLOCK) ){
						syslog (LOG_WARNING, "failed to send notification: %s", strerror (errno));
						close (poll_fd[j].fd);
						poll_fd[j].fd = -1;
					}
				}
			}

			// Execute an event hook
			if ( pcap_session[i].evt_mask & NOTIFY_EXEC ){

				// Expansion was not made...
				if ( cmd_exp->we_wordc == 0 )
					continue;

				pid = fork ();

				if ( pid == -1 ){
					syslog (LOG_ERR, "cannot fork the process: %s", strerror (errno));
					exitno = EXIT_FAILURE;
					goto cleanup;
				}

				// Parent process, carry on...
				if ( pid > 0 )
					continue;

				errno = 0;
				execv (cmd_exp->we_wordv[0], cmd_exp->we_wordv);

				// This code gets executed only if execv(3) fails. Wrapping
				// this code in a condition is unneccessary.
				syslog (LOG_WARNING, "cannot execute event hook in '%s': %s", pcap_session[i].filter_name, strerror (errno));

				exitno = EXIT_FAILURE;
				goto cleanup;
			}
		}

#ifdef DBG_AVG_LOOP_SPEED
		clock_avg = (clock_avg + (clock () - clock_start)) / 2;

		syslog (LOG_DEBUG, "Average loop speed: %lf", (double) (clock_avg / CLOCKS_PER_SEC));
#endif
	}

	syslog (LOG_INFO, "Etherpoke shutdown (signal %u)", exitno);

cleanup:
	closelog ();

	if ( pcap_session != NULL ){
		for ( i = 0; i < filter_cnt; i++ )
			session_data_free (&(pcap_session[i]));
		free (pcap_session);
	}

	if ( poll_fd != NULL )
		free (poll_fd);

	if ( sock != -1 )
		close (sock);

	config_unload (&etherpoke_conf);

	path_free (&path_config);

	return exitno;
}
Ejemplo n.º 7
0
int main(int argc, char **argv)
{
    /* default values for command line arguments (see also static variables) */
    const char *if_name = PCAPPRINT_DEF_IFNAME;
    int snaplen = PCAPPRINT_DEF_SNAPLEN;
    const char *dlt_name = PCAPPRINT_DEF_DLTNAME;
    int num_pkts = -1;
    const char *pcap_filename = NULL;
    const char *bpf_expr = NULL;
    int rfmon = 0;

    /* process command line options */
    const char *usage = "usage: pcap-print [options]\n";

    int c;
    while ((c = getopt(argc, argv, ":1234ab:c:dfhi:mNqr:s:tVy:")) != -1) {
        switch (c) {
        case '1':
        case '2':
        case '3':
        case '4':
            enabled_layers[c-'0'-1]++;
            break;
        case 'a':
            /* arbitrary "big" number */
            enabled_layers[0] = 100;
            enabled_layers[1] = 100;
            enabled_layers[2] = 100;
            enabled_layers[3] = 100;
            break;
        case 'b':
            bpf_expr = optarg;
            break;
        case 'c':
            num_pkts = atoi(optarg);
            break;
        case 'd':
            tsfmt = TS_CTIME;
            break;
        case 'f':
            print_fcs = 1;
            break;
        case 'h':
            printf(usage);
            printf(
                "    -1  print data-link header (e.g. Ethernet)\n"
                "    -2  print network header (e.g. IP)\n"
                "    -3  print transport header (e.g. TCP)\n"
                "    -4  print application header (e.g. HTTP)\n"
                "    -a  print ALL headers, with maximum verbosity\n"
                "    -b  specify a BPF filter\n"
                "    -c  print only first N packets\n"
                "    -d  print absolute timestamp in date format\n"
                "    -f  print FCS for MAC headers\n"
                "    -h  print usage information and quit\n"
                "    -i  network interface on which to capture packets"
                " (default: %s)\n"
                "    -m  set rfmon mode on interface\n"
                "    -N  number packets as they are printed\n"
                "    -q  suppress printing of packet-parsing errors\n"
                "    -r  read from pcap file instead of live capture\n"
                "    -s  capture size in bytes (default: %d)\n"
                "    -t  print absolute timestamp\n"
                "    -V  print pcap version and quit\n"
                "    -y  datalink type for capturing interface (default: %s)\n",
                PCAPPRINT_DEF_IFNAME, PCAPPRINT_DEF_SNAPLEN, PCAPPRINT_DEF_DLTNAME);
            exit(0);
            break;
        case 'i':
            if_name = optarg;
            break;
        case 'm':
            rfmon = 1;
            break;
        case 'N':
            use_numbering = 1;
            break;
        case 'q':
            quiet = 1;
            break;
        case 'r':
            pcap_filename = optarg;
            break;
        case 's':
            snaplen = (int)strtol(optarg, (char **)NULL, 10);
            break;
        case 't':
            tsfmt = TS_ABS;
            break;
        case 'V':
            printf("%s\n", pcap_lib_version());
            exit(0);
            break;
        case 'y':
            dlt_name = optarg;
            break;
        case ':':
            errx(1, "option -%c requires an operand", optopt);
            break;
        case '?':
            errx(1, "unrecognized option: -%c", optopt);
            break;
        default:
            /* unhandled option indicates programming error */
            assert(0);
        }
    }

    /* if no layers we specified, use defaults (hard-coded) */
    if (! (enabled_layers[0] || enabled_layers[1] || enabled_layers[2] ||
            enabled_layers[3])) {
        enabled_layers[1] = 1;
        enabled_layers[2] = 1;
    }

    /* create pcap handle (either from file or from live capture) */
    char ebuf[PCAP_ERRBUF_SIZE];
    *ebuf = '\0';

    /* used only if a BPF program (filter) is specified */
    bpf_u_int32 netnum = 0, netmask = 0;

    if (pcap_filename != NULL) {
        /* "capture" from file */
        if (strcmp(if_name, PCAPPRINT_DEF_IFNAME) != 0)
            warnx("warning: -i option ignored when -f option is present");

        if (snaplen != PCAPPRINT_DEF_SNAPLEN)
            warnx("warning: -s option ignored when -f option is present");

        if (strcmp(dlt_name, PCAPPRINT_DEF_DLTNAME) != 0)
            warnx("warning: -y option ignored when -f option is present");

        pcap_h = pcap_open_offline(pcap_filename, ebuf);
        if (pcap_h == NULL)
            errx(1, "pcap_open_offline: %s", ebuf);
        else if (*ebuf)
            warnx("pcap_open_offline: %s", ebuf);

        /* read dlt from file */
        dlt = pcap_datalink(pcap_h);
    } else {
        /* live capture */
        dlt = pcap_datalink_name_to_val(dlt_name);
        if (dlt < 0)
            err(1, "invalid data link type %s", dlt_name);

        pcap_h = pcap_create(if_name, ebuf);
        if (pcap_h == NULL)
            errx(1, "pcap_create: %s", ebuf);

        if (pcap_set_snaplen(pcap_h, snaplen) != 0)
            errx(1, "pcap_set_snaplen: %s", pcap_geterr(pcap_h));

        if (pcap_set_promisc(pcap_h, 1) != 0)
            errx(1, "pcap_set_promisc: %s", pcap_geterr(pcap_h));

        if (rfmon) {
            if (pcap_can_set_rfmon(pcap_h) == 0)
                errx(1, "cannot set rfmon mode on device %s", if_name);

            if (pcap_set_rfmon(pcap_h, 1) != 0)
                errx(1, "pcap_set_rfmon: %s", pcap_geterr(pcap_h));
        }

        if (pcap_set_buffer_size(pcap_h, PCAPPRINT_BPF_BUFSIZE) != 0)
            errx(1, "pcap_set_buffer_size: %s", pcap_geterr(pcap_h));

        if (pcap_set_timeout(pcap_h, PCAPPRINT_READ_TIMEOUT) != 0)
            errx(1, "pcap_set_timeout: %s", pcap_geterr(pcap_h));

        if (pcap_lookupnet(if_name, &netnum, &netmask, ebuf) == -1)
            errx(1, "pcap_lookupnet: %s", ebuf);

        if (pcap_activate(pcap_h) != 0)
            errx(1, "pcap_activate: %s", pcap_geterr(pcap_h));

        /*
         * the following calls must be done AFTER pcap_activate():
         * pcap_setfilter
         * pcap_setdirection
         * pcap_set_datalink
         * pcap_getnonblock
         * pcap_setnonblock
         * pcap_stats
         * all reads/writes
         */

        if (pcap_set_datalink(pcap_h, dlt) == -1)
            errx(1, "pcap_set_datalink: %s", pcap_geterr(pcap_h));

        int r, yes = 1;
        int pcap_fd = pcap_get_selectable_fd(pcap_h);
        if ((r = ioctl(pcap_fd, BIOCIMMEDIATE, &yes)) == -1)
            err(1, "BIOCIMMEDIATE");
        else if (r != 0)
            warnx("BIOCIMMEDIATE returned %d", r);

        /* set up signal handlers */
        if (signal(SIGINT, SIG_IGN) != SIG_IGN)
            signal(SIGINT, signal_handler);
        if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
            signal(SIGTERM, signal_handler);
    }

    /* apply BPF filter (if one was specified) */
    if (bpf_expr != NULL) {
        struct bpf_program bpf;
        if (pcap_compile(pcap_h, &bpf, bpf_expr, 1 /*optimize*/, netmask) == -1)
            errx(1, "pcap_compile: %s", pcap_geterr(pcap_h));

        if (pcap_setfilter(pcap_h, &bpf) == -1)
            errx(1, "pcap_setfilter: %s", pcap_geterr(pcap_h));
    }

    /* start reading packets */
    if (pcap_loop(pcap_h, num_pkts, handle_packet, NULL) == -1)
        errx(1, "pcap_loop: %s", pcap_geterr(pcap_h));

    if (pcap_filename == NULL) { /* if live capture.. */
        printf("%u packets captured\n", pkt_count);
        struct pcap_stat stats;
        if (pcap_stats(pcap_h, &stats) != 0) {
            warnx("pcap_stats: %s", pcap_geterr(pcap_h));
        } else {
            printf("%u packets received by filter\n"
                "%u packets dropped by kernel\n", stats.ps_recv, stats.ps_drop);
        }
    }

    pcap_close(pcap_h);
    return 0;
}