+void handleDCCPpacket(int rcv_socket, int send_socket){
+ int rlen=1500;
+ unsigned char rbuffer[rlen];
+ char pbuf[1000];
+ ipaddr_ptr_t rcv_addr;
+ socklen_t rcv_addr_len;
+ struct dccp_hdr *dhdr;
+
+ /*Memory for socket address*/
+ rcv_addr_len=sizeof(struct sockaddr_storage);
+ rcv_addr.gen=malloc(rcv_addr_len);
+ if(rcv_addr.gen==NULL){
+ dbgprintf(0,"Error: Can't Allocate Memory!\n");
+ exit(1);
+ }
+
+ /*Receive Packet*/
+ rcv_addr_len=sizeof(struct sockaddr_storage);
+ if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,rcv_addr.gen,&rcv_addr_len))<0){
+ dbgprintf(0, "Error on receive from DCCP socket (%s)\n",strerror(errno));
+ }
+
+ if(rcv_addr.gen->sa_family!=ip_type){ //confirm IP type
+ dbgprintf(1, "DCCP packet on %s. Tossing.\n", (ip_type==AF_INET) ? "IPv4" : "IPv6");
+ 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;
+ }
+
+ /*Check IP source*/
+ if(rcv_addr.gen->sa_family==AF_INET){
+ /*IPv4*/
+ if(memcmp(&rcv_addr.ipv4->sin_addr,&dest_addr.ipv4->sin_addr,
+ sizeof(dest_addr.ipv4->sin_addr))!=0){ //not from destination
+ dbgprintf(1,"DCCP packet from 3rd host\n");
+ free(rcv_addr.gen);
+ return;
+ }
+ }else{
+ /*IPv6*/
+ if(memcmp(&rcv_addr.ipv6->sin6_addr, &dest_addr.ipv6->sin6_addr,
+ sizeof(dest_addr.ipv6->sin6_addr))!=0){ //not from destination
+ dbgprintf(1,"DCCP packet from 3rd host\n");
+ free(rcv_addr.gen);
+ return;
+ }
+ }
+
+ /*DCCP checks*/
+ dhdr=(struct dccp_hdr*)rbuffer;
+ if(dhdr->dccph_sport!=htons(dest_port)){
+ dbgprintf(1,"DCCP packet with wrong Source Port\n");
+ free(rcv_addr.gen);
+ return;
+ }
+ if(dhdr->dccph_dport!=htons(dest_port)){
+ dbgprintf(1,"DCCP packet with wrong Destination Port\n");
+ free(rcv_addr.gen);
+ return;
+ }
+
+ /*Print Message*/
+ if(dhdr->dccph_type==DCCP_PKT_RESET){
+ /*Print Message*/
+ if(ip_type==AF_INET){
+ dbgprintf(0, "Got DCCP RESET from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
+ }else{
+ dbgprintf(0, "Got DCCP RESET from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
+ }
+ /*Nothing else to do*/
+ }
+ if(dhdr->dccph_type==DCCP_PKT_RESPONSE){
+ /*Print Message*/
+ if(ip_type==AF_INET){
+ dbgprintf(0, "Got DCCP RESPONSE from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
+ }else{
+ dbgprintf(0, "Got DCCP RESPONSE from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
+ }
+ /*Send Close back*/
+ }
+ if(dhdr->dccph_type==DCCP_PKT_SYNC || dhdr->dccph_type==DCCP_PKT_SYNCACK){
+ /*Print Message*/
+ if(ip_type==AF_INET){
+ dbgprintf(0, "Got DCCP SYNC from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
+ }else{
+ dbgprintf(0, "Got DCCP SYNC from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
+ }
+ /*Send Reset*/
+ }
+
+ free(rcv_addr.gen);
+}
+
+void handleICMPpacket(int rcv_socket){
+ int rlen=1500;
+ unsigned char rbuffer[rlen];
+ char pbuf[1000];
+ ipaddr_ptr_t rcv_addr;
+ socklen_t rcv_addr_len;
+ struct icmphdr *icmp4;
+ struct icmp6_hdr *icmp6;
+
+ /*Memory for socket address*/
+ rcv_addr_len=sizeof(struct sockaddr_storage);
+ rcv_addr.gen=malloc(rcv_addr_len);
+ if(rcv_addr.gen==NULL){
+ dbgprintf(0,"Error: Can't Allocate Memory!\n");
+ exit(1);
+ }
+
+ /*Receive Packet*/
+ if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,rcv_addr.gen,&rcv_addr_len))<0){
+ dbgprintf(0, "Error on receive from ICMP socket (%s)\n",strerror(errno));
+ }
+
+ if(rcv_addr.gen->sa_family!=ip_type){ //confirm IP type
+ dbgprintf(1, "ICMP packet on %s. Tossing.\n", (ip_type==AF_INET) ? "IPv4" : "IPv6");
+ free(rcv_addr.gen);
+ return;
+ }
+
+ if(rcv_addr.gen->sa_family==AF_INET){
+ /*IPv4*/
+ if(rlen < sizeof(struct icmphdr)){ //check packet size
+ dbgprintf(1, "Packet smaller than possible ICMP packet!\n");
+ free(rcv_addr.gen);
+ 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);
+ free(rcv_addr.gen);
+ return;
+ }
+
+ /*Print Message*/
+ dbgprintf(0, "Got ICMPv4 type %i from %s\n", icmp4->type,
+ inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
+
+ }else{
+ /*IPv6*/
+ if(rlen < sizeof(struct icmp6_hdr)){ //check packet size
+ dbgprintf(1, "Packet smaller than possible ICMP packet!\n");
+ free(rcv_addr.gen);
+ 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);
+ free(rcv_addr.gen);
+ return;
+ }
+
+ /*Print Message*/
+ dbgprintf(0, "Got ICMPv6 type %i from %s\n", icmp6->icmp6_type,
+ inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
+ }
+
+ free(rcv_addr.gen);
+}
+
+void buildRequestPacket(unsigned char* buffer, int *len){