#36, basic raw mode tunnel works

src/iodine.c

@@ -189,58 +189,77 @@ is_sending()
 }
 
 static int
-read_dns(int fd, char *buf, int buflen)
+read_dns(int dns_fd, int tun_fd, char *buf, int buflen) /* FIXME: tun_fd needed for raw handling */
 {
 	struct sockaddr_in from;
 	char data[64*1024];
 	socklen_t addrlen;
 	struct query q;
-	int rv;
 	int r;
 
 	addrlen = sizeof(struct sockaddr);
-	if ((r = recvfrom(fd, data, sizeof(data), 0, 
+	if ((r = recvfrom(dns_fd, data, sizeof(data), 0, 
 			  (struct sockaddr*)&from, &addrlen)) == -1) {
 		warn("recvfrom");
 		return 0;
 	}
 
-	rv = dns_decode(buf, buflen, &q, QR_ANSWER, data, r);
+	if (conn == CONN_DNS_NULL) {
+		int rv;
 
-	/* decode the data header, update seqno and frag before next request */
+		rv = dns_decode(buf, buflen, &q, QR_ANSWER, data, r);
-	if (rv >= 2) {
-		downstream_seqno = (buf[1] >> 5) & 7;
-		downstream_fragment = (buf[1] >> 1) & 15;
-	}
-
-
-	if (is_sending()) {
-		if (chunkid == q.id) {
-			/* Got ACK on sent packet */
-			outpkt.offset += outpkt.sentlen;
-			if (outpkt.offset == outpkt.len) {
-				/* Packet completed */
-				outpkt.offset = 0;
-				outpkt.len = 0;
-				outpkt.sentlen = 0;
-
-				/* If the ack contains unacked frag number but no data, 
-				 * send a ping to ack the frag number and get more data*/
-				if (rv == 2 && (
-					downstream_seqno != down_ack_seqno ||
-					downstream_fragment != down_ack_fragment
-					)) {
-					
-					send_ping(fd);
-				}
-			} else {
-				/* More to send */
-				send_chunk(fd);
-			}
 
+		/* decode the data header, update seqno and frag before next request */
+		if (rv >= 2) {
+			downstream_seqno = (buf[1] >> 5) & 7;
+			downstream_fragment = (buf[1] >> 1) & 15;
 		}
+
+
+		if (is_sending()) {
+			if (chunkid == q.id) {
+				/* Got ACK on sent packet */
+				outpkt.offset += outpkt.sentlen;
+				if (outpkt.offset == outpkt.len) {
+					/* Packet completed */
+					outpkt.offset = 0;
+					outpkt.len = 0;
+					outpkt.sentlen = 0;
+
+					/* If the ack contains unacked frag number but no data, 
+					 * send a ping to ack the frag number and get more data*/
+					if (rv == 2 && (
+						downstream_seqno != down_ack_seqno ||
+						downstream_fragment != down_ack_fragment
+						)) {
+						
+						send_ping(dns_fd);
+					}
+				} else {
+					/* More to send */
+					send_chunk(dns_fd);
+				}
+			}
+		}
+		return rv;
+	} else { /* CONN_RAW_UDP */
+		unsigned long datalen;
+		char buf[64*1024];
+		int raw_user;
+
+		/* minimum length */
+		if (r < RAW_HDR_LEN) return 0;
+		/* should start with header */
+		if (memcmp(data, raw_header, RAW_HDR_IDENT_LEN)) return 0;
+		/* should be data packet */
+		if (RAW_HDR_GET_CMD(data) != RAW_HDR_CMD_DATA) return 0;
+
+		raw_user = RAW_HDR_GET_USR(data);
+		if (uncompress((uint8_t*)buf, &datalen, (uint8_t*) &data[RAW_HDR_LEN], r) == Z_OK) {
+			write_tun(tun_fd, buf, datalen);
+		}
+		return 0;
 	}
-	return rv;
 }
 
 
@@ -283,7 +302,7 @@ tunnel_dns(int tun_fd, int dns_fd)
 	char buf[64*1024];
 	size_t read;
 
-	if ((read = read_dns(dns_fd, buf, sizeof(buf))) <= 2) 
+	if ((read = read_dns(dns_fd, tun_fd, buf, sizeof(buf))) <= 2) 
 		return -1;
 
 	if (downstream_seqno != inpkt.seqno) {
@@ -578,7 +597,7 @@ handshake_version(int dns_fd, int *seed)
 		r = select(dns_fd + 1, &fds, NULL, NULL, &tv);
 
 		if(r > 0) {
-			read = read_dns(dns_fd, in, sizeof(in));
+			read = read_dns(dns_fd, 0, in, sizeof(in));
 			
 			if(read <= 0) {
 				if (read == 0) {
@@ -646,7 +665,7 @@ handshake_login(int dns_fd, int seed)
 		r = select(dns_fd + 1, &fds, NULL, NULL, &tv);
 
 		if(r > 0) {
-			read = read_dns(dns_fd, in, sizeof(in));
+			read = read_dns(dns_fd, 0, in, sizeof(in));
 			
 			if(read <= 0) {
 				warn("read");
@@ -707,7 +726,7 @@ handshake_raw_udp(int dns_fd, int seed)
 		r = select(dns_fd + 1, &fds, NULL, NULL, &tv);
 
 		if(r > 0) {
-			len = read_dns(dns_fd, in, sizeof(in));
+			len = read_dns(dns_fd, 0, in, sizeof(in));
 			if (len == 5 && in[0] == 'I') {
 				/* Received IP address */
 				remoteaddr = (in[1] & 0xff);
@@ -800,7 +819,7 @@ handshake_case_check(int dns_fd)
 		r = select(dns_fd + 1, &fds, NULL, NULL, &tv);
 
 		if(r > 0) {
-			read = read_dns(dns_fd, in, sizeof(in));
+			read = read_dns(dns_fd, 0, in, sizeof(in));
 			
 			if (read > 0) {
 				if (in[0] == 'z' || in[0] == 'Z') {
@@ -864,7 +883,7 @@ handshake_switch_codec(int dns_fd)
 		r = select(dns_fd + 1, &fds, NULL, NULL, &tv);
 
 		if(r > 0) {
-			read = read_dns(dns_fd, in, sizeof(in));
+			read = read_dns(dns_fd, 0, in, sizeof(in));
 			
 			if (read > 0) {
 				if (strncmp("BADLEN", in, 6) == 0) {
@@ -918,7 +937,7 @@ handshake_autoprobe_fragsize(int dns_fd)
 			r = select(dns_fd + 1, &fds, NULL, NULL, &tv);
 
 			if(r > 0) {
-				read = read_dns(dns_fd, in, sizeof(in));
+				read = read_dns(dns_fd, 0, in, sizeof(in));
 				
 				if (read > 0) {
 					/* We got a reply */
@@ -989,7 +1008,7 @@ handshake_set_fragsize(int dns_fd, int fragsize)
 		r = select(dns_fd + 1, &fds, NULL, NULL, &tv);
 
 		if(r > 0) {
-			read = read_dns(dns_fd, in, sizeof(in));
+			read = read_dns(dns_fd, 0, in, sizeof(in));
 			
 			if (read > 0) {
 				int accepted_fragsize;

src/iodined.c

@@ -123,6 +123,9 @@ check_user_and_ip(int userid, struct query *q)
 	if (!users[userid].active) {
 		return 1;
 	}
+	if (users[userid].last_pkt + 60 < time(NULL)) {
+		return 1;
+	}
 
 	/* return early if IP checking is disabled */
 	if (!check_ip) {
@@ -133,6 +136,24 @@ check_user_and_ip(int userid, struct query *q)
 	return memcmp(&(users[userid].host), &(tempin->sin_addr), sizeof(struct in_addr));
 }
 
+static void
+send_raw(int fd, char *buf, int buflen, int user, int cmd, struct query *q)
+{
+	char packet[4096];
+	int len;
+
+	len = MIN(sizeof(packet) - RAW_HDR_LEN, buflen);
+
+	memcpy(packet, raw_header, RAW_HDR_LEN);
+	memcpy(&packet[RAW_HDR_LEN], buf, len);
+
+	len += RAW_HDR_LEN;
+	packet[RAW_HDR_CMD] = cmd | (user & 0x0F);
+
+	sendto(fd, packet, len, 0, &q->from, q->fromlen);
+}
+
+
 static int
 tunnel_tun(int tun_fd, int dns_fd)
 {
@@ -155,17 +176,22 @@ tunnel_tun(int tun_fd, int dns_fd)
 	outlen = sizeof(out);
 	compress2((uint8_t*)out, &outlen, (uint8_t*)in, read, 9);
 
-	/* if another packet is queued, throw away this one. TODO build queue */
+	if (users[userid].conn == CONN_DNS_NULL) {
-	if (users[userid].outpacket.len == 0) {
+		/* if another packet is queued, throw away this one. TODO build queue */
-		memcpy(users[userid].outpacket.data, out, outlen);
+		if (users[userid].outpacket.len == 0) {
-		users[userid].outpacket.len = outlen;
+			memcpy(users[userid].outpacket.data, out, outlen);
-		users[userid].outpacket.offset = 0;
+			users[userid].outpacket.len = outlen;
-		users[userid].outpacket.sentlen = 0;
+			users[userid].outpacket.offset = 0;
-		users[userid].outpacket.seqno = (++users[userid].outpacket.seqno & 7);
+			users[userid].outpacket.sentlen = 0;
-		users[userid].outpacket.fragment = 0;
+			users[userid].outpacket.seqno = (++users[userid].outpacket.seqno & 7);
+			users[userid].outpacket.fragment = 0;
+			return outlen;
+		} else {
+			return 0;
+		}
+	} else { /* CONN_RAW_UDP */
+		send_raw(dns_fd, out, outlen, userid, RAW_HDR_CMD_DATA, &users[userid].q);
 		return outlen;
-	} else {
-		return 0;
 	}
 }
 
@@ -790,7 +816,7 @@ tunnel(int tun_fd, int dns_fd, int bind_fd)
  		if (i==0) {	
 			int j;
  			for (j = 0; j < USERS; j++) {
- 				if (users[j].q.id != 0) {
+ 				if (users[j].q.id != 0 && users[j].conn == CONN_DNS_NULL) {
 					send_chunk(dns_fd, j);
  				}
  			}
@@ -848,23 +874,6 @@ handle_full_packet(int tun_fd, int userid)
 	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;
-
-	len = MIN(sizeof(packet) - RAW_HDR_LEN, buflen);
-
-	memcpy(packet, raw_header, RAW_HDR_LEN);
-	memcpy(&packet[RAW_HDR_LEN], buf, len);
-
-	len += RAW_HDR_LEN;
-	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, int userid)
 {
@@ -931,7 +940,6 @@ raw_decode(char *packet, int len, struct query *q, int dns_fd, int tun_fd)
 	if (memcmp(packet, raw_header, RAW_HDR_IDENT_LEN)) return 0;
 
 	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 */

src/user.c

@@ -106,7 +106,7 @@ users_waiting_on_reply()
 	for (i = 0; i < USERS; i++) {
 		if (users[i].active && !users[i].disabled && 
 			users[i].last_pkt + 60 > time(NULL) &&
-			users[i].q.id != 0) {
+			users[i].q.id != 0 && users[i].conn == CONN_DNS_NULL) {
 			ret++;
 		}
 	}
@@ -144,7 +144,9 @@ all_users_waiting_to_send()
 	for (i = 0; i < USERS; i++) {
 		if (users[i].active && !users[i].disabled &&
 			users[i].last_pkt + 60 > now &&
-			users[i].outpacket.len == 0) {
+			((users[i].outpacket.len == 0 && users[i].conn == CONN_DNS_NULL) 
+				|| users[i].conn == CONN_RAW_UDP)) {
+
 			ret = 0;
 			break;
 		}