Exit if too big

src/algo_rr.c

@@ -205,6 +205,8 @@ int algo_rr_on_datagram(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo
   struct evt_core_fdinfo *to_fdinfo = NULL;
   uint16_t min_pkt;
   char url[255];
+  size_t health_packet_size = sizeof(bp->ip.ap.fmt.headers) - sizeof(bp->ip.ap.fmt.content.health);
+  size_t max_size = sizeof(struct internet_packet) - health_packet_size;
 
   if (ctx->verbose > 1) fprintf(stderr, "    [algo/rr] Read a UDP packet on URL %s\n", fdinfo->url);
 
@@ -230,13 +232,24 @@ int algo_rr_on_datagram(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo
   bp->ip.ap.fmt.content.clear.id = rr->sent_content_id;
   min_pkt = rr->sent_content_id;
   rr->sent_content_id++;
+  if (bp->ip.ap.fmt.headers.size > max_size) {
+    fprintf(stderr, "Packet is too big to be relayed. Oops...\n");
+    exit(EXIT_FAILURE);
+  }
 
   // 4. Append redundancy if needed
   if (app_ctx->ap.redundant_data == 1) {
-    min_pkt = rr->prev_packet.ap.fmt.content.clear.id;
+    size_t current_size = get_full_size (bp);
-    append_buffer(&bp->ip.ap, bp->ap_count, &rr->prev_packet.ap); // We append previous packet
+    size_t final_size = current_size + rr->prev_packet.ap.fmt.headers.size;
+    if (final_size <= max_size) {
+      min_pkt = rr->prev_packet.ap.fmt.content.clear.id;
+      append_buffer(&bp->ip.ap, bp->ap_count, &rr->prev_packet.ap); // We append previous packet
+      bp->ap_count++;
+    } else if (ctx->verbose) {
+      fprintf(stderr, "    [algo/rr] Can't append redundancy (current=%ld, after=%ld, max=%ld)\n", current_size, final_size, max_size);
+    }
+
     append_buffer(&rr->prev_packet.ap, 0, &bp->ip.ap); // We store current packet for next time
-    bp->ap_count++;
   }
 
   // 5. Append health packet

src/packet.h

@@ -80,6 +80,8 @@ struct udp_target {
   int ref_count;
 };
 
+size_t get_full_size(struct buffer_packet* bp);
+
 enum FD_STATE read_packet_from_tcp(int fd, struct buffer_packet* bp);
 enum FD_STATE write_packet_to_tcp(int fd, struct buffer_packet* bp);
 enum FD_STATE write_packet_to_udp(int fd, struct buffer_packet* bp, struct udp_target* udp_t);