Stupid IPv4/IPv6 differences on raw socket reception

diff --git a/dccpping.c b/dccpping.c
index 2fd8075d26279265a5cb5272afc09dfadb6df4ec..e3f99f1c4e7bfb121fd7fd020ff405a1f260822d 100644 (file)
--- a/dccpping.c
+++ b/dccpping.c
@@ -336,6 +336,8 @@ void handleDCCPpacket(int rcv_socket, int send_socket){
        ipaddr_ptr_t rcv_addr;
        socklen_t rcv_addr_len;
        struct dccp_hdr *dhdr;
+       unsigned char* ptr;
+       struct iphdr* iph;
 
        /*Memory for socket address*/
        rcv_addr_len=sizeof(struct sockaddr_storage);
@@ -357,13 +359,6 @@ void handleDCCPpacket(int rcv_socket, int send_socket){
                return;
        }
 
-       if(rlen < sizeof(struct dccp_hdr)){ //check packet size
-               dbgprintf(1, "Packet smaller than possible DCCP packet received on DCCP socket\n");
-               free(rcv_addr.gen);
-               return;
-       }
-
-       /*Check IP source*/
        if(rcv_addr.gen->sa_family==AF_INET){
                /*IPv4*/
                if(memcmp(&rcv_addr.ipv4->sin_addr,&dest_addr.ipv4->sin_addr,
@@ -372,6 +367,14 @@ void handleDCCPpacket(int rcv_socket, int send_socket){
                        free(rcv_addr.gen);
                        return;
                }
+               if(rlen < sizeof(struct dccp_hdr)+sizeof(struct iphdr)){ //check packet size
+
+                       dbgprintf(1, "Packet smaller than possible DCCP packet received on DCCP socket\n");
+                       free(rcv_addr.gen);
+                       return;
+               }
+               iph=(struct iphdr*)rbuffer;
+               ptr=rbuffer+iph->ihl*4;
        }else{
                /*IPv6*/
                if(memcmp(&rcv_addr.ipv6->sin6_addr, &dest_addr.ipv6->sin6_addr,
@@ -380,12 +383,19 @@ void handleDCCPpacket(int rcv_socket, int send_socket){
                        free(rcv_addr.gen);
                        return;
                }
+               if(rlen < sizeof(struct dccp_hdr)){ //check packet size
+
+                       dbgprintf(1, "Packet smaller than possible DCCP packet received on DCCP socket\n");
+                       free(rcv_addr.gen);
+                       return;
+               }
+               ptr=rbuffer;
        }
 
        /*DCCP checks*/
-       dhdr=(struct dccp_hdr*)rbuffer;
+       dhdr=(struct dccp_hdr*)ptr;
        if(dhdr->dccph_sport!=htons(dest_port)){
-               dbgprintf(1,"DCCP packet with wrong Source Port\n");
+               dbgprintf(1,"DCCP packet with wrong Source Port (%i)\n", ntohs(dhdr->dccph_sport));
                free(rcv_addr.gen);
                return;
        }
@@ -437,17 +447,17 @@ void handleICMP4packet(int rcv_socket){
 
        /*Receive Packet*/
        if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,(struct sockaddr*)&rcv_addr,&rcv_addr_len))<0){
-               dbgprintf(0, "Error on receive from ICMP socket (%s)\n",strerror(errno));
+               dbgprintf(0, "Error on receive from ICMPv4 socket (%s)\n",strerror(errno));
        }
 
        if(rlen < sizeof(struct icmphdr)){ //check packet size
-               dbgprintf(1, "Packet smaller than possible ICMP packet!\n");
+               dbgprintf(1, "Packet smaller than possible ICMPv4 packet!\n");
                return;
        }
 
        icmp4=(struct icmphdr*)rbuffer;
        if(icmp4->type!=3 && icmp4->type!=11){ //check icmp types
-               dbgprintf(1, "Tossing ICMP packet of type %i\n", icmp4->type);
+               dbgprintf(1, "Tossing ICMPv4 packet of type %i\n", icmp4->type);
                return;
        }
 
@@ -466,18 +476,18 @@ void handleICMP6packet(int rcv_socket){
 
        /*Receive Packet*/
        if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,(struct sockaddr*)&rcv_addr,&rcv_addr_len))<0){
-               dbgprintf(0, "Error on receive from ICMP socket (%s)\n",strerror(errno));
+               dbgprintf(0, "Error on receive from ICMPv6 socket (%s)\n",strerror(errno));
        }
 
        if(rlen < sizeof(struct icmp6_hdr)){ //check packet size
-               dbgprintf(1, "Packet smaller than possible ICMP packet!\n");
+               dbgprintf(1, "Packet smaller than possible ICMPv6 packet!\n");
                return;
        }
 
        icmp6=(struct icmp6_hdr*)rbuffer;
        if(icmp6->icmp6_type!=1 && icmp6->icmp6_type!=2 && icmp6->icmp6_type!=3
                        && icmp6->icmp6_type!=4){ //check icmp types
-               dbgprintf(1, "Tossing ICMP packet of type %i\n", icmp6->icmp6_type);
+               dbgprintf(1, "Tossing ICMPv6 packet of type %i\n", icmp6->icmp6_type);
                return;
        }