int
main(int argc, char **argv)
{
char *nameserv_host;
char *topdomain;
char *errormsg;
#ifndef WINDOWS32
struct passwd *pw;
#endif
char *username;
char password[33];
int foreground;
char *newroot;
char *context;
char *device;
char *pidfile;
int choice;
int tun_fd;
int dns_fd;
int max_downstream_frag_size;
int autodetect_frag_size;
int retval;
int raw_mode;
int lazymode;
int selecttimeout;
int hostname_maxlen;
#ifdef OPENBSD
int rtable = 0;
#endif
struct sockaddr_storage nameservaddr;
int nameservaddr_len;
int nameserv_family;
nameserv_host = NULL;
topdomain = NULL;
errormsg = NULL;
#ifndef WINDOWS32
pw = NULL;
#endif
username = NULL;
memset(password, 0, 33);
srand(time(NULL));
foreground = 0;
newroot = NULL;
context = NULL;
device = NULL;
pidfile = NULL;
autodetect_frag_size = 1;
max_downstream_frag_size = 3072;
retval = 0;
raw_mode = 1;
lazymode = 1;
selecttimeout = 4;
hostname_maxlen = 0xFF;
nameserv_family = AF_UNSPEC;
#ifdef WINDOWS32
WSAStartup(req_version, &wsa_data);
#endif
srand((unsigned) time(NULL));
client_init();
#if !defined(BSD) && !defined(__GLIBC__)
__progname = strrchr(argv[0], '/');
if (__progname == NULL)
__progname = argv[0];
else
__progname++;
#endif
while ((choice = getopt(argc, argv, "46vfhru:t:d:R:P:m:M:F:T:O:L:I:")) != -1) {
switch(choice) {
case '4':
nameserv_family = AF_INET;
break;
case '6':
nameserv_family = AF_INET6;
break;
case 'v':
version();
/* NOTREACHED */
break;
case 'f':
foreground = 1;
break;
case 'h':
help();
/* NOTREACHED */
break;
case 'r':
raw_mode = 0;
break;
case 'u':
username = optarg;
break;
case 't':
newroot = optarg;
break;
case 'd':
device = optarg;
break;
#ifdef OPENBSD
case 'R':
rtable = atoi(optarg);
break;
#endif
case 'P':
strncpy(password, optarg, sizeof(password));
password[sizeof(password)-1] = 0;
/* XXX: find better way of cleaning up ps(1) */
memset(optarg, 0, strlen(optarg));
break;
case 'm':
autodetect_frag_size = 0;
max_downstream_frag_size = atoi(optarg);
break;
case 'M':
hostname_maxlen = atoi(optarg);
if (hostname_maxlen > 255)
hostname_maxlen = 255;
if (hostname_maxlen < 10)
hostname_maxlen = 10;
break;
case 'z':
context = optarg;
break;
case 'F':
pidfile = optarg;
break;
case 'T':
if (client_set_qtype(optarg))
errx(5, "Invalid query type '%s'", optarg);
break;
case 'O': /* not -D, is Debug in server */
client_set_downenc(optarg);
break;
case 'L':
lazymode = atoi(optarg);
if (lazymode > 1)
lazymode = 1;
if (lazymode < 0)
lazymode = 0;
if (!lazymode)
selecttimeout = 1;
break;
case 'I':
selecttimeout = atoi(optarg);
if (selecttimeout < 1)
selecttimeout = 1;
break;
default:
usage();
/* NOTREACHED */
}
}
check_superuser(usage);
argc -= optind;
argv += optind;
switch (argc) {
case 1:
nameserv_host = get_resolvconf_addr();
topdomain = strdup(argv[0]);
break;
case 2:
nameserv_host = argv[0];
topdomain = strdup(argv[1]);
break;
default:
usage();
/* NOTREACHED */
}
if (max_downstream_frag_size < 1 || max_downstream_frag_size > 0xffff) {
warnx("Use a max frag size between 1 and 65535 bytes.\n");
usage();
/* NOTREACHED */
}
if (nameserv_host) {
nameservaddr_len = get_addr(nameserv_host, DNS_PORT, nameserv_family, 0, &nameservaddr);
if (nameservaddr_len < 0) {
errx(1, "Cannot lookup nameserver '%s': %s ",
nameserv_host, gai_strerror(nameservaddr_len));
}
client_set_nameserver(&nameservaddr, nameservaddr_len);
} else {
warnx("No nameserver found - not connected to any network?\n");
usage();
/* NOTREACHED */
}
if(check_topdomain(topdomain, &errormsg)) {
warnx("Invalid topdomain: %s", errormsg);
usage();
/* NOTREACHED */
}
client_set_selecttimeout(selecttimeout);
client_set_lazymode(lazymode);
client_set_topdomain(topdomain);
client_set_hostname_maxlen(hostname_maxlen);
if (username != NULL) {
#ifndef WINDOWS32
if ((pw = getpwnam(username)) == NULL) {
warnx("User %s does not exist!\n", username);
usage();
/* NOTREACHED */
}
#endif
}
if (strlen(password) == 0) {
if (NULL != getenv(PASSWORD_ENV_VAR))
snprintf(password, sizeof(password), "%s", getenv(PASSWORD_ENV_VAR));
else
read_password(password, sizeof(password));
}
client_set_password(password);
if ((tun_fd = open_tun(device)) == -1) {
retval = 1;
goto cleanup1;
}
if ((dns_fd = open_dns_from_host(NULL, 0, nameservaddr.ss_family, AI_PASSIVE)) < 0) {
retval = 1;
goto cleanup2;
}
#ifdef OPENBSD
if (rtable > 0)
socket_setrtable(dns_fd, rtable);
#endif
signal(SIGINT, sighandler);
signal(SIGTERM, sighandler);
fprintf(stderr, "Sending DNS queries for %s to %s\n",
topdomain, format_addr(&nameservaddr, nameservaddr_len));
if (client_handshake(dns_fd, raw_mode, autodetect_frag_size, max_downstream_frag_size)) {
retval = 1;
goto cleanup2;
}
if (client_get_conn() == CONN_RAW_UDP) {
fprintf(stderr, "Sending raw traffic directly to %s\n", client_get_raw_addr());
}
fprintf(stderr, "Connection setup complete, transmitting data.\n");
if (foreground == 0)
do_detach();
if (pidfile != NULL)
do_pidfile(pidfile);
if (newroot != NULL)
do_chroot(newroot);
if (username != NULL) {
#ifndef WINDOWS32
gid_t gids[1];
gids[0] = pw->pw_gid;
if (setgroups(1, gids) < 0 || setgid(pw->pw_gid) < 0 || setuid(pw->pw_uid) < 0) {
warnx("Could not switch to user %s!\n", username);
usage();
/* NOTREACHED */
}
#endif
}
if (context != NULL)
do_setcon(context);
client_tunnel(tun_fd, dns_fd);
cleanup2:
close_dns(dns_fd);
close_tun(tun_fd);
cleanup1:
return retval;
}
int
main(int argc, char **argv)
{
char *errormsg = NULL;
#ifndef WINDOWS32
struct passwd *pw = NULL;
#endif
int choice = -1;
int retval = 0;
char *username = NULL;
char *newroot = NULL;
char *context = NULL;
char *device = NULL;
char *pidfile = NULL;
int remote_forward_port = 0;
char *nameserv_host = NULL;
struct sockaddr_storage nameservaddr;
int nameservaddr_len = 0;
int nameserv_family = AF_UNSPEC;
#ifdef WINDOWS32
WSAStartup(req_version, &wsa_data);
#endif
#if !defined(BSD) && !defined(__GLIBC__)
__progname = strrchr(argv[0], '/');
if (__progname == NULL)
__progname = argv[0];
else
__progname++;
#endif
#define OPT_RDOMAIN 0x80
#define OPT_NODROP 0x81
/* each option has format:
* char *name, int has_arg, int *flag, int val */
static struct option iodine_args[] = {
{"version", no_argument, 0, 'v'},
{"help", no_argument, 0, 'h'},
{"stats", optional_argument, 0, 'V'},
{"context", required_argument, 0, 'z'},
{"rdomain", required_argument, 0, OPT_RDOMAIN},
{"chrootdir", required_argument, 0, 't'},
{"preset", required_argument, 0, 'Y'},
{"proxycommand", no_argument, 0, 'R'},
// {"nodrop", no_argument, 0, OPT_NODROP},
{"remote", required_argument, 0, 'R'},
{NULL, 0, 0, 0}
};
/* Pre-parse command line to get preset
* This is so that all options override preset values regardless of order in command line */
int optind_orig = optind, preset_id = -1;
static char *iodine_args_short = "46vfDhrY:s:V:c:C:i:j:u:t:d:R:P:w:W:m:M:F:T:O:L:I:";
while ((choice = getopt_long(argc, argv, iodine_args_short, iodine_args, NULL))) {
/* Check if preset has been found yet so we don't process any other options */
if (preset_id < 0) {
if (choice == -1) {
/* reached end of command line and no preset specified - use default */
preset_id = 0;
} else if (choice == 'Y') {
/* find index of preset */
if (optarg) {
for (int i = 0; i < NUM_CLIENT_PRESETS; i++) {
if (toupper(optarg[0]) == client_presets[i].short_name) {
preset_id = i;
break;
}
}
}
} else if (choice == '?') {
usage();
/* Not reached */
} else {
/* skip all other options until we find preset */
continue;
}
if (preset_id < 0) {
/* invalid preset or none specified */
fprintf(stderr, "Invalid preset or none specified with -Y or --preset!\n");
print_presets(2);
usage();
/* not reached */
}
memcpy(&this, client_presets[preset_id].preset_data, sizeof(struct client_instance));
/* Reset optind to reparse command line */
optind = optind_orig;
continue;
} else if (choice == -1) {
break;
}
/* Once a preset is used, it is copied into memory. This way other
* options can override preset values regardless of order in command line */
switch (choice) {
case '4':
nameserv_family = AF_INET;
break;
case '6':
nameserv_family = AF_INET6;
break;
case 'v':
version();
/* NOTREACHED */
break;
case 'V':
this.stats = atoi(optarg);
if (this.stats < 0)
this.stats = 0;
break;
case 'f':
this.foreground = 1;
break;
case 'D':
this.debug++;
break;
case 'h':
help();
/* NOTREACHED */
break;
case 'r':
this.raw_mode = 0;
break;
case 'u':
username = optarg;
break;
case 't':
newroot = optarg;
break;
case 'd':
device = optarg;
break;
#ifdef OPENBSD
case OPT_RDOMAIN:
rtable = atoi(optarg);
break;
#endif
case 'R':
/* Argument format: [host:]port */
if (!optarg) break;
this.use_remote_forward = 1;
remote_forward_port = parse_tcp_forward_option(optarg);
break;
case OPT_NODROP:
// TODO implement TCP-over-tun optimisations
break;
case 'P':
strncpy(this.password, optarg, sizeof(this.password));
this.password[sizeof(this.password)-1] = 0;
/* XXX: find better way of cleaning up ps(1) */
memset(optarg, 0, strlen(optarg));
break;
case 'm':
this.autodetect_frag_size = 0;
this.max_downstream_frag_size = atoi(optarg);
break;
case 'M':
this.hostname_maxlen = atoi(optarg);
if (this.hostname_maxlen > 255)
this.hostname_maxlen = 255;
if (this.hostname_maxlen < 10)
this.hostname_maxlen = 10;
break;
case 'z':
context = optarg;
break;
case 'F':
pidfile = optarg;
break;
case 'T':
if (client_set_qtype(optarg))
errx(5, "Invalid query type '%s'", optarg);
break;
case 'O':
if ((this.downenc = parse_encoding(optarg)) == 0)
errx(6, "Invalid encoding type '%s'", optarg);
break;
case 'L':
this.lazymode = atoi(optarg);
if (this.lazymode > 1)
this.lazymode = 1;
if (this.lazymode < 0)
this.lazymode = 0;
break;
case 'I':
this.max_timeout_ms = strtod(optarg, NULL) * 1000;
if (this.autodetect_server_timeout) {
this.server_timeout_ms = this.max_timeout_ms / 2;
}
break;
case 'i':
this.server_timeout_ms = strtod(optarg, NULL) * 1000;
this.autodetect_server_timeout = 0;
break;
case 'j':
this.downstream_timeout_ms = strtod(optarg, NULL) * 1000;
if (this.autodetect_server_timeout) {
this.autodetect_server_timeout = 0;
this.server_timeout_ms = 4000;
}
break;
case 's':
this.send_interval_ms = atoi(optarg);
if (this.send_interval_ms < 0)
this.send_interval_ms = 0;
case 'w':
this.windowsize_down = atoi(optarg);
break;
case 'W':
this.windowsize_up = atoi(optarg);
break;
case 'c':
this.compression_down = atoi(optarg) & 1;
break;
case 'C':
this.compression_up = atoi(optarg) & 1;
break;
case 'Y':
/* Already processed preset: ignore */
continue;
default:
usage();
/* NOTREACHED */
}
}
srand((unsigned) time(NULL));
this.rand_seed = (uint16_t) rand();
this.chunkid = (uint16_t) rand();
this.running = 1;
check_superuser(usage);
argc -= optind;
argv += optind;
if (this.debug) {
fprintf(stderr, "Debug level %d enabled, will stay in foreground.\n", this.debug);
fprintf(stderr, "Add more -D switches to set higher debug level.\n");
this.foreground = 1;
}
this.nameserv_hosts_len = argc - 1;
if (this.nameserv_hosts_len <= 0)
/* if no hosts specified, use resolv.conf */
this.nameserv_hosts_len = 1;
// Preallocate memory with expected number of hosts
this.nameserv_hosts = malloc(sizeof(char *) * this.nameserv_hosts_len);
this.nameserv_addrs = malloc(sizeof(struct sockaddr_storage) * this.nameserv_hosts_len);
if (argc == 0) {
usage();
/* NOT REACHED */
} else if (argc == 1) {
this.nameserv_hosts[0] = get_resolvconf_addr();
} else if (argc > 1)
for (int h = 0; h < this.nameserv_hosts_len; h++)
this.nameserv_hosts[h] = strdup(argv[h + 1]);
this.topdomain = strdup(argv[0]);
for (int n = 0; n < this.nameserv_hosts_len; n++) {
nameserv_host = this.nameserv_hosts[n];
if (!nameserv_host) {
errx(1, "Error processing nameserver hostnames!");
}
nameservaddr_len = get_addr(nameserv_host, DNS_PORT, nameserv_family, 0, &nameservaddr);
if (nameservaddr_len < 0) {
errx(1, "Cannot lookup nameserver '%s': %s ",
nameserv_host, gai_strerror(nameservaddr_len));
}
memcpy(&this.nameserv_addrs[n], &nameservaddr, sizeof(struct sockaddr_storage));
this.nameserv_addrs_len ++;
nameserv_host = NULL;
}
if (this.nameserv_addrs_len <= 0 || !this.nameserv_hosts[0]) {
warnx("No nameservers found - not connected to any network?");
usage();
}
if (this.max_downstream_frag_size < 10 || this.max_downstream_frag_size > MAX_FRAGSIZE) {
warnx("Use a max frag size between 10 and %d bytes.", MAX_FRAGSIZE);
usage();
/* NOTREACHED */
}
if(check_topdomain(this.topdomain, &errormsg)) {
warnx("Invalid topdomain: %s", errormsg);
usage();
/* NOTREACHED */
}
int max_ws = MAX_SEQ_ID / 2;
if (this.windowsize_up < 1 || this.windowsize_down < 1 ||
this.windowsize_up > max_ws || this.windowsize_down > max_ws) {
warnx("Window sizes (-w or -W) must be between 0 and %d!", max_ws);
usage();
}
if (this.max_timeout_ms < 100) {
warnx("Target interval (-I) must be greater than 0.1 seconds!");
usage();
}
if ((this.server_timeout_ms < 100 || this.server_timeout_ms >= this.max_timeout_ms)
&& !this.autodetect_server_timeout) {
warnx("Server timeout (-i) must be greater than 0.1 sec and less than target interval!");
usage();
}
if (this.downstream_timeout_ms < 100) {
warnx("Downstream fragment timeout must be more than 0.1 sec to prevent excessive retransmits.");
usage();
}
if (!this.lazymode && this.max_timeout_ms > 1000) {
fprintf(stderr, "Warning: Target interval of >1 second in immediate mode will cause high latency.\n");
}
if (username != NULL) {
#ifndef WINDOWS32
if ((pw = getpwnam(username)) == NULL) {
warnx("User %s does not exist!", username);
usage();
/* NOTREACHED */
}
#else
warnx("Warning: Cannot switch user on Windows systems.");
#endif
}
if (strlen(this.password) == 0) {
if (NULL != getenv(PASSWORD_ENV_VAR))
snprintf(this.password, sizeof(this.password), "%s", getenv(PASSWORD_ENV_VAR));
else
read_password(this.password, sizeof(this.password));
}
if (!this.use_remote_forward) {
if ((this.tun_fd = open_tun(device)) == -1) {
retval = 1;
goto cleanup;
}
}
if ((this.dns_fd = open_dns_from_host(NULL, 0, nameservaddr.ss_family, AI_PASSIVE)) < 0) {
retval = 1;
goto cleanup;
}
#ifdef OPENBSD
if (rtable > 0)
socket_setrtable(dns_fd, rtable);
#endif
signal(SIGINT, sighandler);
signal(SIGTERM, sighandler);
fprintf(stderr, "Sending DNS queries for %s to ", this.topdomain);
for (int a = 0; a < this.nameserv_addrs_len; a++)
fprintf(stderr, "%s%s", format_addr(&this.nameserv_addrs[a], sizeof(struct sockaddr_storage)),
(a != this.nameserv_addrs_len - 1) ? ", " : "");
fprintf(stderr, "\n");
if (this.remote_forward_addr.ss_family != AF_UNSPEC)
fprintf(stderr, "Requesting TCP data forwarding from server to %s:%d\n",
format_addr(&this.remote_forward_addr, sizeof(struct sockaddr_storage)), remote_forward_port);
if (client_handshake()) {
retval = 1;
goto cleanup;
}
if (this.conn == CONN_RAW_UDP) {
fprintf(stderr, "Sending raw UDP traffic directly to %s\n", client_get_raw_addr());
}
fprintf(stderr, "Connection setup complete, transmitting data.\n");
if (this.foreground == 0)
do_detach();
if (pidfile != NULL)
do_pidfile(pidfile);
if (newroot != NULL)
do_chroot(newroot);
if (username != NULL) {
#ifndef WINDOWS32
gid_t gids[1];
gids[0] = pw->pw_gid;
if (setgroups(1, gids) < 0 || setgid(pw->pw_gid) < 0 || setuid(pw->pw_uid) < 0) {
warnx("Could not switch to user %s!\n", username);
usage();
/* NOTREACHED */
}
#endif
}
if (context != NULL)
do_setcon(context);
client_tunnel();
cleanup:
if (this.use_remote_forward)
close(STDOUT_FILENO);
close_socket(this.dns_fd);
close_socket(this.tun_fd);
#ifdef WINDOWS32
WSACleanup();
#endif
return retval;
}