Added -n to set NS ip, updated docs, added checks

This commit is contained in:
Erik Ekman 2008-09-14 13:21:11 +00:00
parent 2eb78f9e8c
commit 55176af538
3 changed files with 52 additions and 15 deletions

View File

@ -13,7 +13,8 @@ CHANGES:
a nameserver on localhost. Use -b port to enable.
- iodine client now shuts down if it detects a server restart.
- iodined now replies to NS request on its own domain, fixes issue #33.
The destination IP address is sent as reply.
The destination IP address is sent as reply. Use -n to specify
a specific IP address to return (if behind NAT etc).
- Upstream data is now Base64 encoded if relay server preserves case and
supports the plus (+) character in domain names, fixes #16.

View File

@ -27,17 +27,23 @@ iodine, iodined \- tunnel IPv4 over DNS
.B iodined [-c] [-s] [-f] [-D] [-u
.I user
.B ] [-P
.I password
.B ] [-t
.I chrootdir
.B ] [-d
.I device
.B ] [-m
.I mtu
.B ] [-l
.I listen_ip
.B ] [-d
.I device
.B ]
.B ] [-p
.I port
.B ] [-n
.I external ip
.B ] [-b
.I dnsport
.B ] [-P
.I password
.B ]
.I tunnel_ip
.I topdomain
.SH DESCRIPTION
@ -68,14 +74,14 @@ Drop privileges and run as user 'user' after setting up tunnel.
.B -t chrootdir
Chroot to 'chrootdir' after setting up tunnel.
.TP
.B -d device
Use the TUN device 'device' instead of the normal one, which is dnsX on Linux
and otherwise tunX.
.TP
.B -P password
Use 'password' to authenticate. If not used,
.B stdin
will be used as input. Only the first 32 characters will be used.
.TP
.B -d device
Use the TUN device 'device' instead of the normal one, which is dnsX on Linux
and otherwise tunX.
.SS Server Options:
.TP
.B -c
@ -100,6 +106,14 @@ connections.
Make the server listen on 'port' instead of 53 for traffic.
.B Note:
You must make sure the dns requests are forwarded to this port yourself.
.TP
.B -n external ip
The IP address to return in NS responses. Default is to return the address used
as destination in the query.
.TP
.B -b dnsport
If this port is specified, all incoming requests not inside the tunnel domain
will be forwarded to this port on localhost, to be handled by a real dns.
.SS Client Arguments:
.TP
.B nameserver

View File

@ -60,6 +60,8 @@ static int check_ip;
static int my_mtu;
static in_addr_t my_ip;
static in_addr_t ns_ip;
static int bind_port;
static int debug;
@ -353,6 +355,10 @@ handle_ns_request(int dns_fd, struct query *q)
char buf[64*1024];
int len;
if (ns_ip != INADDR_ANY) {
memcpy(&q->destination.s_addr, &ns_ip, sizeof(in_addr_t));
}
len = dns_encode_ns_response(buf, sizeof(buf), q, topdomain);
if (debug >= 1) {
@ -636,7 +642,7 @@ usage() {
printf("Usage: %s [-v] [-h] [-c] [-s] [-f] [-D] [-u user] "
"[-t chrootdir] [-d device] [-m mtu] "
"[-l ip address to listen on] [-p port] [-b port] [-P password]"
"[-l ip address to listen on] [-p port] [-n external ip] [-b dnsport] [-P password]"
" tunnel_ip topdomain\n", __progname);
exit(2);
}
@ -648,7 +654,7 @@ help() {
printf("iodine IP over DNS tunneling server\n");
printf("Usage: %s [-v] [-h] [-c] [-s] [-f] [-D] [-u user] "
"[-t chrootdir] [-d device] [-m mtu] "
"[-l ip address to listen on] [-p port] [-b port] [-P password]"
"[-l ip address to listen on] [-p port] [-n external ip] [-b dnsport] [-P password]"
" tunnel_ip topdomain\n", __progname);
printf(" -v to print version info and exit\n");
printf(" -h to print this help and exit\n");
@ -664,6 +670,7 @@ help() {
printf(" -l ip address to listen on for incoming dns traffic "
"(default 0.0.0.0)\n");
printf(" -p port to listen on for incoming dns traffic (default 53)\n");
printf(" -n ip to respond with to NS queries\n");
printf(" -b port to forward normal DNS queries to (on localhost)\n");
printf(" -P password used for authentication (max 32 chars will be used)\n");
printf("tunnel_ip is the IP number of the local tunnel interface.\n");
@ -711,6 +718,7 @@ main(int argc, char **argv)
mtu = 1024;
listen_ip = INADDR_ANY;
port = 53;
ns_ip = INADDR_ANY;
check_ip = 1;
skipipconfig = 0;
debug = 0;
@ -729,7 +737,7 @@ main(int argc, char **argv)
srand(time(NULL));
fw_query_init();
while ((choice = getopt(argc, argv, "vcsfhDu:t:d:m:l:p:b:P:")) != -1) {
while ((choice = getopt(argc, argv, "vcsfhDu:t:d:m:l:p:n:b:P:")) != -1) {
switch(choice) {
case 'v':
version();
@ -767,6 +775,9 @@ main(int argc, char **argv)
case 'p':
port = atoi(optarg);
break;
case 'n':
ns_ip = inet_addr(optarg);
break;
case 'b':
bind_enable = 1;
bind_port = atoi(optarg);
@ -794,6 +805,13 @@ main(int argc, char **argv)
if (argc != 2)
usage();
my_ip = inet_addr(argv[0]);
if (my_ip == INADDR_NONE) {
warnx("Bad IP address to use inside tunnel.\n");
usage();
}
topdomain = strdup(argv[1]);
if(strlen(topdomain) <= 128) {
@ -848,7 +866,12 @@ main(int argc, char **argv)
warnx("Bad IP address to listen on.\n");
usage();
}
if (ns_ip == INADDR_NONE) {
warnx("Bad IP address to return as nameserver.\n");
usage();
}
if (strlen(password) == 0)
read_password(password, sizeof(password));
@ -863,7 +886,6 @@ main(int argc, char **argv)
if ((bind_fd = open_dns(0, INADDR_ANY)) == -1)
goto cleanup3;
my_ip = inet_addr(argv[0]);
my_mtu = mtu;
init_users(my_ip);