DEST_UNREACHABLE,
TTL_EXPIRATION,
TOO_BIG,
- PARAMETER_PROBLEM
+ PARAMETER_PROBLEM,
+ DCCP_ERROR
};
char* response_label[]= {
"Unknown",
"Destination Unreachable",
"TTL Expiration",
"Packet Too Big",
-"DCCP Not Supported (Parameter Problem)"
+"DCCP Not Supported (Parameter Problem)",
+"Protocol Error (DCCP Reset)"
};
void handleICMP6packet(int rcv_socket);
void buildRequestPacket(unsigned char* buffer, int *len, int seq);
void updateRequestPacket(unsigned char* buffer, int *len, int seq);
+void sendClose(int seq, u_int16_t ack_h, u_int32_t ack_l, int socket);
+void sendReset(int seq, u_int16_t ack_h, u_int32_t ack_l, int socket);
int logPacket(int seq);
int logResponse(ipaddr_ptr_t *src, int seq, int type);
void clearQueue();
socklen_t rcv_addr_len;
struct dccp_hdr *dhdr;
struct dccp_hdr_reset *dhdr_re;
+ struct dccp_hdr_ext *dhdre;
struct dccp_hdr_response *dhdr_rp;
struct dccp_hdr_ack_bits *dhdr_sync;
unsigned char* ptr;
return;
}
dhdr_re=(struct dccp_hdr_reset*)(ptr+sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext));
- logResponse(&rcv_addr, ntohl(dhdr_re->dccph_reset_ack.dccph_ack_nr_low), RESET);
+
+ /*Log*/
+ if(dhdr_re->dccph_reset_code==DCCP_RESET_CODE_NO_CONNECTION){
+ logResponse(&rcv_addr, ntohl(dhdr_re->dccph_reset_ack.dccph_ack_nr_low), RESET);
+ }else{
+ logResponse(&rcv_addr, ntohl(dhdr_re->dccph_reset_ack.dccph_ack_nr_low), DCCP_ERROR);
+ }
/*Nothing else to do*/
}
if(dhdr->dccph_type==DCCP_PKT_RESPONSE){
dbgprintf(1, "Error: Response packet too small!");
return;
}
+
+ /*Log*/
+ dhdre=(struct dccp_hdr_ext*)(ptr+sizeof(struct dccp_hdr));
dhdr_rp=(struct dccp_hdr_response*)(ptr+sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext));
logResponse(&rcv_addr,ntohl(dhdr_rp->dccph_resp_ack.dccph_ack_nr_low),RESPONSE);
- /*TODO:Send Close back*/
+
+ /*Send Close*/
+ sendClose(ntohl(dhdr_rp->dccph_resp_ack.dccph_ack_nr_low),
+ dhdr->dccph_seq, dhdre->dccph_seq_low,send_socket);
}
if(dhdr->dccph_type==DCCP_PKT_SYNC || dhdr->dccph_type==DCCP_PKT_SYNCACK){
if(rlen < (ptr-rbuffer)+sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext)+sizeof(struct dccp_hdr_ack_bits)){
dbgprintf(1, "Error: Response packet too small!");
return;
}
+
+ /*Log*/
+ dhdre=(struct dccp_hdr_ext*)(ptr+sizeof(struct dccp_hdr));
dhdr_sync=(struct dccp_hdr_ack_bits*)(ptr+sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext));
logResponse(&rcv_addr,ntohl(dhdr_sync->dccph_ack_nr_low),SYNC);
- /*TODO:Send Reset*/
+
+ /*Send Reset*/
+ sendReset(ntohl(dhdr_sync->dccph_ack_nr_low),
+ dhdr->dccph_seq, dhdre->dccph_seq_low,send_socket);
}
free(rcv_addr.gen);
ip4hdr=(struct iphdr*)(rbuffer+sizeof(struct icmphdr));
if(memcmp(&src_addr.ipv4->sin_addr,&ip4hdr->saddr,sizeof(src_addr.ipv4->sin_addr))!=0){
/*Source address doesn't match*/
+ dbgprintf(1,"Tossing ICMPv4 packet because the embedded IPv4 source address isn't us\n");
free(rcv_addr.gen);
return;
}
if(memcmp(&dest_addr.ipv4->sin_addr,&ip4hdr->daddr,sizeof(dest_addr.ipv4->sin_addr))!=0){
/*Destination address doesn't match*/
+ dbgprintf(1,"Tossing ICMPv4 packet because the embedded IPv4 destination address isn't our target\n");
free(rcv_addr.gen);
return;
}
if(ip4hdr->protocol!=IPPROTO_DCCP){
/*Not DCCP!*/
+ dbgprintf(1,"Tossing ICMPv4 packet because the embedded packet isn't DCCP\n");
free(rcv_addr.gen);
return;
}
dhdr=(struct dccp_hdr*)(rbuffer+sizeof(struct icmphdr)+ip4hdr->ihl*4);
if(dhdr->dccph_dport!=htons(dest_port)){
/*DCCP Destination Ports don't match*/
+ dbgprintf(1,"Tossing ICMPv4 packet because the embedded packet doesn't have our DCCP destination port\n");
free(rcv_addr.gen);
return;
}
if(dhdr->dccph_sport!=htons(dest_port)){
/*DCCP Source Ports don't match*/
+ dbgprintf(1,"Tossing ICMPv4 packet because the embedded packet doesn't have our DCCP source port\n");
free(rcv_addr.gen);
return;
}
/*Decode IPv6 header*/
ip6hdr=(struct ip6_hdr*)(rbuffer+sizeof(struct icmp6_hdr));
if(memcmp(&src_addr.ipv6->sin6_addr,&ip6hdr->ip6_src,sizeof(src_addr.ipv6->sin6_addr))!=0){
+ dbgprintf(1,"Tossing ICMPv6 packet because the embedded IPv6 source address isn't us\n");
/*Source address doesn't match*/
free(rcv_addr.gen);
return;
}
if(memcmp(&dest_addr.ipv6->sin6_addr,&ip6hdr->ip6_dst,sizeof(dest_addr.ipv6->sin6_addr))!=0){
/*Destination address doesn't match*/
+ dbgprintf(1,"Tossing ICMPv6 packet because the embedded IPv6 destination address isn't our target\n");
free(rcv_addr.gen);
return;
}
if(ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_nxt!=IPPROTO_DCCP){
/*Not DCCP!*/
+ dbgprintf(1,"Tossing ICMPv6 packet because the embedded packet isn't DCCP\n");
free(rcv_addr.gen);
return;
}
dhdr=(struct dccp_hdr*)(rbuffer+sizeof(struct icmp6_hdr)+sizeof(struct ip6_hdr));
if(dhdr->dccph_dport!=htons(dest_port)){
/*DCCP Destination Ports don't match*/
+ dbgprintf(1,"Tossing ICMPv6 packet because the embedded packet doesn't have our DCCP destination port\n");
free(rcv_addr.gen);
return;
}
if(dhdr->dccph_sport!=htons(dest_port)){
/*DCCP Source Ports don't match*/
+ dbgprintf(1,"Tossing ICMPv6 packet because the embedded packet doesn't have our DCCP source port\n");
free(rcv_addr.gen);
return;
}
dhdre=(struct dccp_hdr_ext*)(rbuffer+sizeof(struct icmp6_hdr)+sizeof(struct ip6_hdr)+sizeof(struct dccp_hdr));
-
-
/*Log*/
if(icmp6->icmp6_type==ICMP6_DST_UNREACH){
type=DEST_UNREACHABLE;
return;
}
+void sendClose(int seq, u_int16_t ack_h, u_int32_t ack_l, int socket){
+ unsigned char buffer[1500];
+ struct dccp_hdr *dhdr;
+ struct dccp_hdr_ext *dhdre;
+ struct dccp_hdr_ack_bits *dhd_ack;
+ struct iphdr* ip4hdr;
+ struct ip6_hdr* ip6hdr;
+ int len;
+ int addrlen;
+
+ int ip_hdr_len;
+ int dccp_hdr_len=sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext)+sizeof(struct dccp_hdr_ack_bits);
+
+ memset(buffer, 0, 1500);
+
+ /*IP header*/
+ ip4hdr=NULL;
+ if(ip_type==AF_INET){
+ ip_hdr_len=sizeof(struct iphdr);
+ ip4hdr=(struct iphdr*)buffer;
+ ip4hdr->check=htons(0);
+ memcpy(&ip4hdr->daddr, &dest_addr.ipv4->sin_addr, sizeof(dest_addr.ipv4->sin_addr));
+ ip4hdr->frag_off=htons(0);
+ ip4hdr->id=htons(1);//first
+ ip4hdr->ihl=5;
+ ip4hdr->protocol=IPPROTO_DCCP;
+ memcpy(&ip4hdr->saddr, &src_addr.ipv4->sin_addr, sizeof(src_addr.ipv4->sin_addr));
+ ip4hdr->tos=0;
+ ip4hdr->tot_len=htons(ip_hdr_len+dccp_hdr_len);
+ ip4hdr->ttl=ttl;
+ ip4hdr->version=4;
+ }else{
+ ip_hdr_len=sizeof(struct ip6_hdr);
+ ip6hdr=(struct ip6_hdr*)buffer;
+ memcpy(&ip6hdr->ip6_dst, &dest_addr.ipv6->sin6_addr, sizeof(dest_addr.ipv6->sin6_addr));
+ memcpy(&ip6hdr->ip6_src, &src_addr.ipv6->sin6_addr, sizeof(src_addr.ipv6->sin6_addr));
+ ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_flow=htonl(6<<28); //version, traffic class, flow label
+ ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_hlim=ttl;
+ ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_nxt=IPPROTO_DCCP;
+ ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_plen=htons(dccp_hdr_len);
+ }
+
+ /*DCCP header*/
+ dhdr=(struct dccp_hdr*)(buffer+ip_hdr_len);
+ dhdre=(struct dccp_hdr_ext*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr));
+ dhd_ack=(struct dccp_hdr_ack_bits*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext));
+ dhdr->dccph_ccval=0;
+ dhdr->dccph_checksum=0;
+ dhdr->dccph_cscov=0;
+ dhdr->dccph_doff=dccp_hdr_len/4;
+ dhdr->dccph_dport=htons(dest_port);
+ dhdr->dccph_reserved=0;
+ dhdr->dccph_sport=htons(dest_port);
+ dhdr->dccph_x=1;
+ dhdr->dccph_type=DCCP_PKT_CLOSE;
+ dhdr->dccph_seq2=htonl(0); //Reserved if using 48 bit sequence numbers
+ dhdr->dccph_seq=htonl(0); //High 16bits of sequence number. Always make 0 for simplicity.
+ dhdre->dccph_seq_low=htonl(seq+1);
+ dhd_ack->dccph_ack_nr_high=ack_h;
+ dhd_ack->dccph_ack_nr_low=ack_l;
+
+ /*Checksums*/
+ if(ip_type==AF_INET){
+ dhdr->dccph_checksum=ipv4_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
+ (unsigned char*) &dest_addr.ipv4->sin_addr,
+ (unsigned char*)&src_addr.ipv4->sin_addr, IPPROTO_DCCP);
+ ip4hdr->check=ipv4_chksum(buffer,ip_hdr_len);
+ }else{
+ dhdr->dccph_checksum=ipv6_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
+ (unsigned char*) &dest_addr.ipv6->sin6_addr,
+ (unsigned char*)&src_addr.ipv6->sin6_addr, IPPROTO_DCCP);
+ }
+ len=ip_hdr_len+dccp_hdr_len;
+
+ /*Send*/
+ if(ip_type==AF_INET){
+ addrlen=sizeof(struct sockaddr_in);
+ }else{
+ addrlen=sizeof(struct sockaddr_in6);
+ }
+ if(sendto(socket, &buffer, len, MSG_DONTWAIT,(struct sockaddr*)dest_addr.gen,addrlen)<0){
+ if(errno!=EINTR){
+ dbgprintf(0,"Error: sendto failed\n");
+ }
+ }
+ return;
+}
+
+void sendReset(int seq, u_int16_t ack_h, u_int32_t ack_l, int socket){
+ unsigned char buffer[1500];
+ struct dccp_hdr *dhdr;
+ struct dccp_hdr_ext *dhdre;
+ struct dccp_hdr_reset *dh_re;
+ struct iphdr* ip4hdr;
+ struct ip6_hdr* ip6hdr;
+ int len;
+ int addrlen;
+
+ int ip_hdr_len;
+ int dccp_hdr_len=sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext)+sizeof(struct dccp_hdr_reset);
+
+ memset(buffer, 0, 1500);
+
+ /*IP header*/
+ ip4hdr=NULL;
+ if(ip_type==AF_INET){
+ ip_hdr_len=sizeof(struct iphdr);
+ ip4hdr=(struct iphdr*)buffer;
+ ip4hdr->check=htons(0);
+ memcpy(&ip4hdr->daddr, &dest_addr.ipv4->sin_addr, sizeof(dest_addr.ipv4->sin_addr));
+ ip4hdr->frag_off=htons(0);
+ ip4hdr->id=htons(1);//first
+ ip4hdr->ihl=5;
+ ip4hdr->protocol=IPPROTO_DCCP;
+ memcpy(&ip4hdr->saddr, &src_addr.ipv4->sin_addr, sizeof(src_addr.ipv4->sin_addr));
+ ip4hdr->tos=0;
+ ip4hdr->tot_len=htons(ip_hdr_len+dccp_hdr_len);
+ ip4hdr->ttl=ttl;
+ ip4hdr->version=4;
+ }else{
+ ip_hdr_len=sizeof(struct ip6_hdr);
+ ip6hdr=(struct ip6_hdr*)buffer;
+ memcpy(&ip6hdr->ip6_dst, &dest_addr.ipv6->sin6_addr, sizeof(dest_addr.ipv6->sin6_addr));
+ memcpy(&ip6hdr->ip6_src, &src_addr.ipv6->sin6_addr, sizeof(src_addr.ipv6->sin6_addr));
+ ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_flow=htonl(6<<28); //version, traffic class, flow label
+ ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_hlim=ttl;
+ ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_nxt=IPPROTO_DCCP;
+ ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_plen=htons(dccp_hdr_len);
+ }
+
+ /*DCCP header*/
+ dhdr=(struct dccp_hdr*)(buffer+ip_hdr_len);
+ dhdre=(struct dccp_hdr_ext*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr));
+ dh_re=(struct dccp_hdr_reset*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext));
+ dhdr->dccph_ccval=0;
+ dhdr->dccph_checksum=0;
+ dhdr->dccph_cscov=0;
+ dhdr->dccph_doff=dccp_hdr_len/4;
+ dhdr->dccph_dport=htons(dest_port);
+ dhdr->dccph_reserved=0;
+ dhdr->dccph_sport=htons(dest_port);
+ dhdr->dccph_x=1;
+ dhdr->dccph_type=DCCP_PKT_RESET;
+ dhdr->dccph_seq2=htonl(0); //Reserved if using 48 bit sequence numbers
+ dhdr->dccph_seq=htonl(0); //High 16bits of sequence number. Always make 0 for simplicity.
+ dhdre->dccph_seq_low=htonl(seq+1);
+ dh_re->dccph_reset_ack.dccph_ack_nr_high=ack_h;
+ dh_re->dccph_reset_ack.dccph_ack_nr_low=ack_l;
+ dh_re->dccph_reset_code=DCCP_RESET_CODE_CLOSED;
+ dh_re->dccph_reset_data[0]=0;
+ dh_re->dccph_reset_data[1]=0;
+ dh_re->dccph_reset_data[2]=0;
+
+ /*Checksums*/
+ if(ip_type==AF_INET){
+ dhdr->dccph_checksum=ipv4_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
+ (unsigned char*) &dest_addr.ipv4->sin_addr,
+ (unsigned char*)&src_addr.ipv4->sin_addr, IPPROTO_DCCP);
+ ip4hdr->check=ipv4_chksum(buffer,ip_hdr_len);
+ }else{
+ dhdr->dccph_checksum=ipv6_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
+ (unsigned char*) &dest_addr.ipv6->sin6_addr,
+ (unsigned char*)&src_addr.ipv6->sin6_addr, IPPROTO_DCCP);
+ }
+ len=ip_hdr_len+dccp_hdr_len;
+
+ /*Send*/
+ if(ip_type==AF_INET){
+ addrlen=sizeof(struct sockaddr_in);
+ }else{
+ addrlen=sizeof(struct sockaddr_in6);
+ }
+ if(sendto(socket, &buffer, len, MSG_DONTWAIT,(struct sockaddr*)dest_addr.gen,addrlen)<0){
+ if(errno!=EINTR){
+ dbgprintf(0,"Error: sendto failed\n");
+ }
+ }
+ return;
+}
+
int logPacket(int seq){
struct request *tmp;
projects / dccpping / commitdiff