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);
}
}
}
/* 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);
}
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);
}
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);
}
int CDECL wine_pcap_datalink_name_to_val(const char *name)
{
TRACE("(%s)\n", debugstr_a(name));
return pcap_datalink_name_to_val(name);
}
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 (ðerpoke_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 (ðerpoke_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 (ðerpoke_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 (¤t_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 (ðerpoke_conf);
path_free (&path_config);
return exitno;
}
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;
}