diff --git a/src/common.h b/src/common.h
index 28fc2bb..dd7db6e 100644
--- a/src/common.h
+++ b/src/common.h
@@ -21,8 +21,13 @@
#define RAW_HDR_LEN 4
#define RAW_HDR_IDENT_LEN 3
#define RAW_HDR_CMD 3
-#define RAW_HDR_CMD_LOGIN 0x01
-#define RAW_HDR_CMD_DATA 0x02
+#define RAW_HDR_CMD_LOGIN 0x10
+#define RAW_HDR_CMD_DATA 0x20
+
+#define RAW_HDR_CMD_MASK 0xF0
+#define RAW_HDR_USR_MASK 0x0F
+#define RAW_HDR_GET_CMD(x) ((x)[RAW_HDR_CMD] & RAW_HDR_CMD_MASK)
+#define RAW_HDR_GET_USR(x) ((x)[RAW_HDR_CMD] & RAW_HDR_USR_MASK)
extern const unsigned char raw_header[RAW_HDR_LEN];
#ifdef WINDOWS32
@@ -85,6 +90,12 @@ struct query {
int fromlen;
};
+enum connection {
+ CONN_RAW_UDP,
+ CONN_DNS_NULL,
+ CONN_MAX
+};
+
void check_superuser(void (*usage_fn)(void));
int open_dns(int, in_addr_t);
void close_dns(int);
diff --git a/src/iodine.c b/src/iodine.c
index 9b1dcba..41cb9cc 100644
--- a/src/iodine.c
+++ b/src/iodine.c
@@ -60,6 +60,7 @@ WSADATA wsa_data;
static void send_ping(int fd);
static void send_chunk(int fd);
+static void send_raw_data(int fd);
static int build_hostname(char *buf, size_t buflen,
const char *data, const size_t datalen,
const char *topdomain, struct encoder *encoder);
@@ -94,6 +95,9 @@ static struct encoder *b32;
* Defaults to Base32, can be changed after handshake */
static struct encoder *dataenc;
+/* My connection mode */
+static enum connection conn;
+
#if !defined(BSD) && !defined(__GLIBC__)
static char *__progname;
#endif
@@ -120,7 +124,7 @@ send_query(int fd, char *hostname)
}
static void
-send_raw(int fd, char *buf, int buflen, int cmd)
+send_raw(int fd, char *buf, int buflen, int user, int cmd)
{
char packet[4096];
int len;
@@ -131,7 +135,7 @@ send_raw(int fd, char *buf, int buflen, int cmd)
memcpy(&packet[RAW_HDR_LEN], buf, len);
len += RAW_HDR_LEN;
- packet[RAW_HDR_CMD] = cmd;
+ packet[RAW_HDR_CMD] = cmd | (user & 0x0F);
sendto(fd, packet, len, 0, (struct sockaddr*)&raw_serv, sizeof(raw_serv));
}
@@ -263,7 +267,11 @@ tunnel_tun(int tun_fd, int dns_fd)
outpkt.seqno++;
outpkt.fragment = 0;
- send_chunk(dns_fd);
+ if (conn == CONN_DNS_NULL) {
+ send_chunk(dns_fd);
+ } else {
+ send_raw_data(dns_fd);
+ }
return read;
}
@@ -327,7 +335,7 @@ tunnel(int tun_fd, int dns_fd)
FD_ZERO(&fds);
- if (!is_sending()) {
+ if ((!is_sending()) || conn == CONN_RAW_UDP) {
FD_SET(tun_fd, &fds);
}
FD_SET(dns_fd, &fds);
@@ -340,7 +348,7 @@ tunnel(int tun_fd, int dns_fd)
if (i < 0)
err(1, "select");
- if (i == 0) /* timeout */
+ if (i == 0 && conn == CONN_DNS_NULL) /* timeout */
send_ping(dns_fd);
else {
if (FD_ISSET(tun_fd, &fds)) {
@@ -357,6 +365,12 @@ tunnel(int tun_fd, int dns_fd)
return rv;
}
+static void
+send_raw_data(int dns_fd)
+{
+ send_raw(dns_fd, outpkt.data, outpkt.len, userid, RAW_HDR_CMD_DATA);
+}
+
static void
send_chunk(int fd)
{
@@ -507,11 +521,10 @@ send_ip_request(int fd, int userid)
static void
send_raw_udp_login(int dns_fd, int userid, int seed)
{
- char buf[17];
+ char buf[16];
login_calculate(buf, 16, password, seed + 1);
- buf[16] = userid;
- send_raw(dns_fd, buf, sizeof(buf), RAW_HDR_CMD_LOGIN);
+ send_raw(dns_fd, buf, sizeof(buf), userid, RAW_HDR_CMD_LOGIN);
}
static void
@@ -715,7 +728,7 @@ handshake_raw_udp(int dns_fd, int seed)
if (!remoteaddr) {
fprintf(stderr, " failed to get IP.\n");
- return 1;
+ return 0;
}
fprintf(stderr, " at %s: ", inet_ntoa(server));
fflush(stderr);
@@ -743,16 +756,15 @@ handshake_raw_udp(int dns_fd, int seed)
if(r > 0) {
/* recv() needed for windows, dont change to read() */
len = recv(dns_fd, in, sizeof(in), 0);
- if (len >= (17 + RAW_HDR_LEN)) {
+ if (len >= (16 + RAW_HDR_LEN)) {
char hash[16];
login_calculate(hash, 16, password, seed - 1);
if (memcmp(in, raw_header, RAW_HDR_IDENT_LEN) == 0
- && in[RAW_HDR_CMD] == RAW_HDR_CMD_LOGIN
- && memcmp(&in[RAW_HDR_LEN], hash, sizeof(hash)) == 0
- && in[16 + RAW_HDR_LEN] == userid) {
+ && RAW_HDR_GET_CMD(in) == RAW_HDR_CMD_LOGIN
+ && memcmp(&in[RAW_HDR_LEN], hash, sizeof(hash)) == 0) {
fprintf(stderr, "OK\n");
- return 0;
+ return 1;
}
}
}
@@ -761,7 +773,7 @@ handshake_raw_udp(int dns_fd, int seed)
}
fprintf(stderr, "failed\n");
- return 1;
+ return 0;
}
static int
@@ -1016,22 +1028,24 @@ handshake(int dns_fd, int autodetect_frag_size, int fragsize)
return r;
}
- handshake_raw_udp(dns_fd, seed);
+ if (handshake_raw_udp(dns_fd, seed)) {
+ conn = CONN_RAW_UDP;
+ } else {
+ case_preserved = handshake_case_check(dns_fd);
- case_preserved = handshake_case_check(dns_fd);
-
- if (case_preserved) {
- handshake_switch_codec(dns_fd);
- }
-
- if (autodetect_frag_size) {
- fragsize = handshake_autoprobe_fragsize(dns_fd);
- if (!fragsize) {
- return 1;
+ if (case_preserved) {
+ handshake_switch_codec(dns_fd);
}
- }
- handshake_set_fragsize(dns_fd, fragsize);
+ if (autodetect_frag_size) {
+ fragsize = handshake_autoprobe_fragsize(dns_fd);
+ if (!fragsize) {
+ return 1;
+ }
+ }
+
+ handshake_set_fragsize(dns_fd, fragsize);
+ }
return 0;
}
@@ -1178,6 +1192,7 @@ main(int argc, char **argv)
b32 = get_base32_encoder();
dataenc = get_base32_encoder();
+ conn = CONN_DNS_NULL;
retval = 0;
@@ -1312,7 +1327,11 @@ main(int argc, char **argv)
goto cleanup2;
}
- fprintf(stderr, "Sending queries for %s to %s\n", topdomain, nameserv_addr);
+ if (conn == CONN_DNS_NULL) {
+ fprintf(stderr, "Sending queries for %s to %s\n", topdomain, nameserv_addr);
+ } else {
+ fprintf(stderr, "Sending raw traffic directly to %s\n", inet_ntoa(raw_serv.sin_addr));
+ }
if (foreground == 0)
do_detach();
diff --git a/src/iodined.c b/src/iodined.c
index e1f4b94..60b84ca 100644
--- a/src/iodined.c
+++ b/src/iodined.c
@@ -85,8 +85,9 @@ static int debug;
static char *__progname;
#endif
-static int read_dns(int, struct query *);
+static int read_dns(int, int, struct query *);
static void write_dns(int, struct query *, char *, int);
+static void handle_full_packet(int, int);
static void
sigint(int sig)
@@ -295,15 +296,12 @@ static void
handle_null_request(int tun_fd, int dns_fd, struct query *q, int domain_len)
{
struct in_addr tempip;
- struct ip *hdr;
- unsigned long outlen;
char in[512];
char logindata[16];
char out[64*1024];
char unpacked[64*1024];
char *tmp[2];
int userid;
- int touser;
int version;
int code;
int read;
@@ -589,30 +587,7 @@ handle_null_request(int tun_fd, int dns_fd, struct query *q, int domain_len)
}
if (lastfrag & 1) { /* packet is complete */
- int ret;
- outlen = sizeof(out);
- ret = uncompress((uint8_t*)out, &outlen,
- (uint8_t*)users[userid].inpacket.data, users[userid].inpacket.len);
-
- if (ret == Z_OK) {
- hdr = (struct ip*) (out + 4);
- touser = find_user_by_ip(hdr->ip_dst.s_addr);
-
- if (touser == -1) {
- /* send the uncompressed packet to tun device */
- write_tun(tun_fd, out, outlen);
- } else {
- /* send the compressed packet to other client
- * if another packet is queued, throw away this one. TODO build queue */
- if (users[touser].outpacket.len == 0) {
- memcpy(users[touser].outpacket.data, users[userid].inpacket.data, users[userid].inpacket.len);
- users[touser].outpacket.len = users[userid].inpacket.len;
- }
- }
- } else {
- fprintf(stderr, "Discarded data, uncompress() result: %d\n", ret);
- }
- users[userid].inpacket.len = users[userid].inpacket.offset = 0;
+ handle_full_packet(tun_fd, userid);
}
/* Update seqno and maybe send immediate response packet */
update_downstream_seqno(dns_fd, userid, dn_seq, dn_frag);
@@ -730,7 +705,7 @@ tunnel_dns(int tun_fd, int dns_fd, int bind_fd)
int domain_len;
int inside_topdomain;
- if ((read = read_dns(dns_fd, &q)) <= 0)
+ if ((read = read_dns(dns_fd, tun_fd, &q)) <= 0)
return 0;
if (debug >= 2) {
@@ -820,15 +795,15 @@ tunnel(int tun_fd, int dns_fd, int bind_fd)
}
}
} else {
- if(FD_ISSET(tun_fd, &fds)) {
+ if (FD_ISSET(tun_fd, &fds)) {
tunnel_tun(tun_fd, dns_fd);
continue;
}
- if(FD_ISSET(dns_fd, &fds)) {
+ if (FD_ISSET(dns_fd, &fds)) {
tunnel_dns(tun_fd, dns_fd, bind_fd);
continue;
}
- if(FD_ISSET(bind_fd, &fds)) {
+ if (FD_ISSET(bind_fd, &fds)) {
tunnel_bind(bind_fd, dns_fd);
continue;
}
@@ -839,7 +814,42 @@ tunnel(int tun_fd, int dns_fd, int bind_fd)
}
static void
-send_raw(int fd, char *buf, int buflen, int cmd, struct query *q)
+handle_full_packet(int tun_fd, int userid)
+{
+ unsigned long outlen;
+ char out[64*1024];
+ int touser;
+ int ret;
+
+ outlen = sizeof(out);
+ ret = uncompress((uint8_t*)out, &outlen,
+ (uint8_t*)users[userid].inpacket.data, users[userid].inpacket.len);
+
+ if (ret == Z_OK) {
+ struct ip *hdr;
+
+ hdr = (struct ip*) (out + 4);
+ touser = find_user_by_ip(hdr->ip_dst.s_addr);
+
+ if (touser == -1) {
+ /* send the uncompressed packet to tun device */
+ write_tun(tun_fd, out, outlen);
+ } else {
+ /* send the compressed packet to other client
+ * if another packet is queued, throw away this one. TODO build queue */
+ if (users[touser].outpacket.len == 0) {
+ memcpy(users[touser].outpacket.data, users[userid].inpacket.data, users[userid].inpacket.len);
+ users[touser].outpacket.len = users[userid].inpacket.len;
+ }
+ }
+ } else {
+ fprintf(stderr, "Discarded data, uncompress() result: %d\n", ret);
+ }
+ users[userid].inpacket.len = users[userid].inpacket.offset = 0;
+}
+
+static void
+send_raw(int fd, char *buf, int buflen, int user, int cmd, struct query *q)
{
char packet[4096];
int len;
@@ -850,51 +860,96 @@ send_raw(int fd, char *buf, int buflen, int cmd, struct query *q)
memcpy(&packet[RAW_HDR_LEN], buf, len);
len += RAW_HDR_LEN;
- packet[RAW_HDR_CMD] = cmd;
+ packet[RAW_HDR_CMD] = cmd | (user & 0x0F);
sendto(fd, packet, len, 0, &q->from, q->fromlen);
}
static void
-handle_raw_login(char *packet, int len, struct query *q, int fd)
+handle_raw_login(char *packet, int len, struct query *q, int fd, int userid)
{
- int userid;
char myhash[16];
- if (len < 17) return;
+ if (len < 16) return;
- userid = packet[16];
if (userid < 0 || userid > created_users) return;
if (!users[userid].active) return;
+ /* User sends hash of seed + 1 */
login_calculate(myhash, 16, password, users[userid].seed + 1);
if (memcmp(packet, myhash, 16) == 0) {
+ struct sockaddr_in *tempin;
+
+ /* Update query and time info for user */
+ users[userid].last_pkt = time(NULL);
+ memcpy(&(users[userid].q), q, sizeof(struct query));
+
+ /* Store remote IP number */
+ tempin = (struct sockaddr_in *) &(q->from);
+ memcpy(&(users[userid].host), &(tempin->sin_addr), sizeof(struct in_addr));
+
/* Correct hash, reply with hash of seed - 1 */
+ user_set_conn_type(userid, CONN_RAW_UDP);
users[userid].last_pkt = time(NULL);
login_calculate(myhash, 16, password, users[userid].seed - 1);
- memcpy(packet, myhash, 16);
- send_raw(fd, packet, 17, RAW_HDR_CMD_LOGIN, q);
+ send_raw(fd, myhash, 16, userid, RAW_HDR_CMD_LOGIN, q);
}
}
-static int
-raw_decode(char *packet, int len, struct query *q, int fd)
+static void
+handle_raw_data(char *packet, int len, struct query *q, int dns_fd, int tun_fd, int userid)
{
+ if (check_user_and_ip(userid, q) != 0) {
+ return;
+ }
+
+ /* Update query and time info for user */
+ users[userid].last_pkt = time(NULL);
+ memcpy(&(users[userid].q), q, sizeof(struct query));
+
+ /* copy to packet buffer, update length */
+ users[userid].inpacket.offset = 0;
+ memcpy(users[userid].inpacket.data, packet, len);
+ users[userid].inpacket.len = len;
+
+ if (debug >= 1) {
+ fprintf(stderr, "IN pkt raw, total %d, from user %d\n",
+ users[userid].inpacket.len, userid);
+ }
+
+ handle_full_packet(tun_fd, userid);
+}
+
+static int
+raw_decode(char *packet, int len, struct query *q, int dns_fd, int tun_fd)
+{
+ int raw_user;
+
/* minimum length */
if (len < RAW_HDR_LEN) return 0;
/* should start with header */
if (memcmp(packet, raw_header, RAW_HDR_IDENT_LEN)) return 0;
- if (packet[RAW_HDR_CMD] == RAW_HDR_CMD_LOGIN) {
- handle_raw_login(&packet[RAW_HDR_LEN], len - RAW_HDR_LEN, q, fd);
- } else {
- warnx("Unhandled raw command %02X\n", packet[RAW_HDR_CMD]);
+ raw_user = RAW_HDR_GET_USR(packet);
+ printf("raw %02x\n", packet[RAW_HDR_CMD]);
+ switch (RAW_HDR_GET_CMD(packet)) {
+ case RAW_HDR_CMD_LOGIN:
+ /* Login challenge */
+ handle_raw_login(&packet[RAW_HDR_LEN], len - RAW_HDR_LEN, q, dns_fd, raw_user);
+ break;
+ case RAW_HDR_CMD_DATA:
+ /* Data packet */
+ handle_raw_data(&packet[RAW_HDR_LEN], len - RAW_HDR_LEN, q, dns_fd, tun_fd, raw_user);
+ break;
+ default:
+ warnx("Unhandled raw command %02X from user %d", RAW_HDR_GET_CMD(packet), raw_user);
+ break;
}
return 1;
}
static int
-read_dns(int fd, struct query *q)
+read_dns(int fd, int tun_fd, struct query *q) /* FIXME: tun_fd is because of raw_decode() below */
{
struct sockaddr_in from;
socklen_t addrlen;
@@ -929,7 +984,7 @@ read_dns(int fd, struct query *q)
q->fromlen = addrlen;
/* TODO do not handle raw packets here! */
- if (raw_decode(packet, r, q, fd)) {
+ if (raw_decode(packet, r, q, fd, tun_fd)) {
return 0;
}
if (dns_decode(NULL, 0, q, QR_QUERY, packet, r) < 0) {
@@ -1177,7 +1232,7 @@ main(int argc, char **argv)
}
topdomain = strdup(argv[1]);
- if(strlen(topdomain) <= 128) {
+ if (strlen(topdomain) <= 128) {
if(check_topdomain(topdomain)) {
warnx("Topdomain contains invalid characters.");
usage();
diff --git a/src/user.c b/src/user.c
index b15665b..7250251 100644
--- a/src/user.c
+++ b/src/user.c
@@ -90,6 +90,7 @@ init_users(in_addr_t my_ip, int netbits)
users[i].out_acked_seqno = 0;
users[i].out_acked_fragment = 0;
users[i].fragsize = 4096;
+ users[i].conn = CONN_DNS_NULL;
}
return created_users;
@@ -161,6 +162,8 @@ find_available_user()
if ((!users[i].active || users[i].last_pkt + 60 < time(NULL)) && !users[i].disabled) {
users[i].active = 1;
users[i].last_pkt = time(NULL);
+ users[i].fragsize = 4096;
+ users[i].conn = CONN_DNS_NULL;
ret = i;
break;
}
@@ -176,3 +179,16 @@ user_switch_codec(int userid, struct encoder *enc)
users[userid].encoder = enc;
}
+
+void
+user_set_conn_type(int userid, enum connection c)
+{
+ if (userid < 0 || userid >= USERS)
+ return;
+
+ if (c < 0 || c >= CONN_MAX)
+ return;
+
+ users[userid].conn = c;
+}
+
diff --git a/src/user.h b/src/user.h
index 51fdfbc..ba1e696 100644
--- a/src/user.h
+++ b/src/user.h
@@ -34,6 +34,7 @@ struct user {
int out_acked_seqno;
int out_acked_fragment;
int fragsize;
+ enum connection conn;
};
extern struct user users[USERS];
@@ -44,5 +45,6 @@ int find_user_by_ip(uint32_t);
int all_users_waiting_to_send();
int find_available_user();
void user_switch_codec(int userid, struct encoder *enc);
+void user_set_conn_type(int userid, enum connection c);
#endif