Fixes #15

src/ip.h

@@ -4,6 +4,7 @@
 
 struct ip_common {
     uint8_t version;
+    uint8_t tc;
     uint8_t proto;
     uint8_t hdr_size;
     uint16_t size;
@@ -24,11 +25,13 @@ static inline int ip_get_common (struct ip_common *ic, const uint8_t *data, size
 
     switch (ic->version) {
     case 4:
+        ic->tc = data[1];
         ic->proto = data[9];
         ic->hdr_size = (data[0]&0xF)<<2;
         ic->size = ((data[2]<<8)|data[3]);
         return 0;
     case 6:
+        ic->tc = ((data[0]&0xF)<<4)|(data[1]>>4);
         ic->proto = data[6];
         ic->hdr_size = 40;
         ic->size = ((data[4]<<8)|data[5])+40;

src/main.c

@@ -384,6 +384,8 @@ int main (int argc, char **argv)
 
     size_t send_size = 0;
     size_t send_limit = 0;
+    int send_tc = 0;
+    int send_next_tc = 0;
 
     while (!gt.quit) {
         FD_SET(tun_fd, &rfds);
@@ -438,16 +440,26 @@ int main (int argc, char **argv)
 
                 send_size += r;
 
-                if (send_size<=mtu)
+                int update_tc = (ic.tc&0xFC)>(send_tc&0xFC);
+
+                if (send_size<=mtu) {
                     send_limit = send_size;
+                    if ((ic.tc&0xFC)>(send_tc&0xFC))
+                        send_tc = ic.tc;
+                } else {
+                    if ((ic.tc&0xFC)>(send_next_tc&0xFC))
+                        send_next_tc = ic.tc;
+                }
             }
         }
 
-        if (send_limit && mud_send(mud, send.buf, send_limit)==send_limit) {
+        if (send_limit && mud_send(mud, send.buf, send_limit, send_tc)==send_limit) {
             if (send_size>send_limit)
                 memmove(&send.buf[0], &send.buf[send_limit], send_size-send_limit);
             send_size -= send_limit;
             send_limit = send_size;
+            send_tc = send_next_tc;
+            send_next_tc = 0;
         }
 
         mud_push(mud);