From bda49e5e9254c402acd8f307367c64e18d486fc5 Mon Sep 17 00:00:00 2001
From: gonzalef <kneesbrah@gmail.com>
Date: Mon, 27 Apr 2020 20:08:30 +0200
Subject: [PATCH] work with tlvs check packet length

---
 src/node.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/src/node.c b/src/node.c
index d71c883..2f959b2 100644
--- a/src/node.c
+++ b/src/node.c
@@ -36,16 +36,16 @@ int ask_for_peers(int socket_num) {
         struct in6_addr ip = peer->ip;
         int16_t port = peer->port;
 
-        int ifindex = if_nametoindex("enp3s0");
+        /*int ifindex = if_nametoindex("enp3s0");
         if(ifindex == 0) {
             int ifindex = if_nametoindex("eth0");
             if(ifindex == 0) {
                 perror("if_nametoindex failed");
                 return -1;
             }
-        }
+        }*/
 
-        ifindex = 0;
+        int ifindex = 0;
 
         // Initialize sockaddr
         struct sockaddr_in6 dest;
@@ -687,9 +687,15 @@ int add_message(char * message, int message_len){
 	return 0;
 }
 // We then look at the differents TLVs in the packet.
-int work_with_tlvs(char * data, int16_t packet_len, struct sockaddr_in6 *sender, int socket_num){
+int work_with_tlvs(char * data, int16_t total_packet_len, struct sockaddr_in6 *sender, int socket_num){
+    int16_t packet_len = ntohs(((packet*) data)->length);
 
-    int pos = 0;
+    if(packet_len != total_packet_len - 4) {
+        fprintf(stderr, ">> Length indicated in packet differs from real length of packet received.\n");
+        return -1;
+    }
+
+    int pos = 4;
     unsigned char tlv_len, hash[16];
     char warn[32];
     tlv new_tlv, cur_tlv;
@@ -703,6 +709,7 @@ int work_with_tlvs(char * data, int16_t packet_len, struct sockaddr_in6 *sender,
     packet pack = (packet) {.magic = 95, .version = 1, .length = 0};
     memset(pack.body, 0, 1020);
 
+/*
     int ifindex = if_nametoindex("enp3s0");
     if(ifindex == 0) {
         int ifindex = if_nametoindex("eth0");
@@ -711,6 +718,8 @@ int work_with_tlvs(char * data, int16_t packet_len, struct sockaddr_in6 *sender,
             return -1;
         }
     }
+*/
+    int ifindex = 0;
 
     ifindex = 0;
     while(pos < packet_len) {