1 /******************************************************************************
2 Author: Samuel Jero <sj323707@ohio.edu>
6 Description: Program to ping hosts using DCCP REQ packets to test for DCCP connectivity.
7 ******************************************************************************/
15 #include <sys/types.h>
17 #include <sys/socket.h>
18 #include <sys/select.h>
19 #include <netinet/ip.h>
20 #include <netinet/ip6.h>
21 #include <netinet/in.h>
22 #include <netinet/ip_icmp.h>
23 #include <netinet/icmp6.h>
24 #include <arpa/inet.h>
28 #include <linux/dccp.h>
29 #include "checksums.h"
32 #define MAX(x,y) (x>y ? x : y)
35 struct sockaddr_in *ipv4;
36 struct sockaddr_in6 *ipv6;
40 int debug=0; /*set to 1 to turn on debugging information*/
41 int count=-1; /*Default number of pings (-1 is infinity)*/
42 int dest_port=33434; /*Default port*/
43 int ttl=64; /*Default TTL*/
44 long interval=1000; /*Default delay between pings in ms*/
45 int ip_type=AF_UNSPEC; /*IPv4 or IPv6*/
46 ipaddr_ptr_t dest_addr;
47 ipaddr_ptr_t src_addr;
51 void getAddresses(char *src, char* dst);
53 void handleDCCPpacket(int rcv_socket, int send_socket);
54 void handleICMP4packet(int rcv_socket);
55 void handleICMP6packet(int rcv_socket);
56 void buildRequestPacket(unsigned char* buffer, int *len);
57 void updateRequestPacket(unsigned char* buffer, int *len);
58 void dbgprintf(int level, const char *fmt, ...);
59 void sanitize_environment();
63 /*Parse commandline options*/
64 int main(int argc, char *argv[])
71 sanitize_environment();
73 while ((c = getopt(argc, argv, "64c:p:i:dt:S:")) != -1) {
84 dbgprintf(0, "Error: count must be positive");
89 dest_port = atoi(optarg);
92 interval = (long)(atof(optarg) * 1000.0);
94 fprintf(stderr, "Invalid interval\n");
103 if (ttl < 1 || ttl > 255) {
104 fprintf(stderr, "Invalid TTL\n");
124 getAddresses(src, dst);
125 if(src_addr.gen==NULL || dest_addr.gen==NULL){
126 dbgprintf(0,"Error: Can't determine source or destination address\n");
137 void getAddresses(char *src, char* dst){
138 struct addrinfo hint;
139 struct addrinfo *dtmp, *stmp;
140 struct ifaddrs *temp, *cur;
141 struct sockaddr_in6* iv6;
145 /*Lookup destination Address*/
146 memset(&hint,0,sizeof(struct addrinfo));
147 hint.ai_family=ip_type;
148 hint.ai_flags=AI_V4MAPPED | AI_ADDRCONFIG;
150 if((err=getaddrinfo(dst,NULL,&hint,&dtmp))!=0){
151 dbgprintf(0,"Error: Couldn't lookup destination %s (%s)\n", dst, gai_strerror(err));
155 dbgprintf(0,"Error: Unknown Host %s\n", dst);
158 addrlen=dtmp->ai_addrlen;
159 hint.ai_family=ip_type=dtmp->ai_family;
160 dest_addr.gen=malloc(dtmp->ai_addrlen);
161 if(dest_addr.gen==NULL){
162 dbgprintf(0,"Error: Can't allocate Memory\n");
165 memcpy(dest_addr.gen,dtmp->ai_addr,dtmp->ai_addrlen);
169 /*Get a meaningful source address*/
171 /*Use Commandline arg*/
172 if((err=getaddrinfo(src,NULL,&hint,&stmp))!=0){
173 dbgprintf(0,"Error: Source Address %s is invalid (%s)\n", src, gai_strerror(err));
177 dbgprintf(0,"Error: Unknown Host %s\n", dst);
180 addrlen=stmp->ai_addrlen;
181 src_addr.gen=malloc(stmp->ai_addrlen);
182 if(src_addr.gen==NULL){
183 dbgprintf(0,"Error: Can't allocate Memory\n");
186 memcpy(src_addr.gen,stmp->ai_addr,stmp->ai_addrlen);
190 /*Guess a good source address*/
194 if(cur->ifa_addr==NULL || cur->ifa_addr->sa_family!=ip_type){ /*Not matching ipv4/ipv6 of dest*/
198 if(cur->ifa_flags & IFF_LOOPBACK){ /*Don't use loopback addresses*/
202 if(cur->ifa_addr!=NULL && cur->ifa_addr->sa_family==AF_INET6){
203 iv6=(struct sockaddr_in6*)cur->ifa_addr;
205 if(iv6->sin6_scope_id!=0){ /*Not globally valid address, if ipv6*/
211 src_addr.gen=malloc(sizeof(struct sockaddr_storage));
212 if(src_addr.gen==NULL){
213 dbgprintf(0,"Error: Can't allocate Memory\n");
216 src_addr.gen->sa_family=ip_type;
217 memcpy(src_addr.gen,cur->ifa_addr,addrlen);
226 /*Preform the ping functionality*/
232 unsigned char sbuffer[slen];
234 struct timeval timeout;
235 struct timeval t,delay, add;
239 rs=socket(ip_type, SOCK_RAW ,IPPROTO_RAW);
241 dbgprintf(0, "Error opening raw socket\n");
244 ds=socket(ip_type, SOCK_RAW ,IPPROTO_DCCP);
246 dbgprintf(0, "Error opening raw DCCP socket\n");
249 is4=socket(ip_type,SOCK_RAW,IPPROTO_ICMP);
251 dbgprintf(0,"Error opening raw ICMPv4 socket\n");
254 is6=socket(ip_type,SOCK_RAW,IPPROTO_ICMPV6);
256 dbgprintf(0,"Error opening raw ICMPv6 socket\n");
261 /*Build DCCP packet*/
262 buildRequestPacket(sbuffer,&slen);
263 if(ip_type==AF_INET){
264 addrlen=sizeof(struct sockaddr_in);
266 addrlen=sizeof(struct sockaddr_in6);
271 if(sendto(rs, &sbuffer, slen, MSG_DONTWAIT,(struct sockaddr*)dest_addr.gen,addrlen)<0){
272 dbgprintf(0,"Error: sendto failed\n");
274 if(ip_type==AF_INET){
275 dbgprintf(0, "Sending DCCP Request to %s\n",inet_ntop(ip_type, (void*)&dest_addr.ipv4->sin_addr, pbuf, 1000));
277 dbgprintf(0, "Sending DCCP Request to %s\n",inet_ntop(ip_type, (void*)&dest_addr.ipv6->sin6_addr, pbuf, 1000));
280 /*Use select to wait on packets or until interval has passed*/
281 add.tv_sec=interval/1000;
282 add.tv_usec=(interval%1000)*1000;
283 gettimeofday(&t,NULL);
284 timeradd(&t,&add,&delay);
285 while(timercmp(&t,&delay,<)){
286 /*Prepare for select*/
291 timersub(&delay,&t,&timeout);
294 if(select(MAX(ds+1,MAX(is4+1,is6+1)),&sel, NULL,NULL,&timeout)<0){
295 dbgprintf(0,"Select() error\n");
298 if(FD_ISSET(ds,&sel)){
299 /*Data on the DCCP socket*/
300 handleDCCPpacket(ds,rs);
303 if(FD_ISSET(is4,&sel) && ip_type==AF_INET){
304 /*Data on the ICMPv4 socket*/
305 handleICMP4packet(is4);
307 if(FD_ISSET(is6,&sel) && ip_type==AF_INET6){
308 /*Data on the ICMPv6 socket*/
309 handleICMP6packet(is6);
311 gettimeofday(&t,NULL);
323 updateRequestPacket(sbuffer,&slen);
332 void handleDCCPpacket(int rcv_socket, int send_socket){
334 unsigned char rbuffer[rlen];
336 ipaddr_ptr_t rcv_addr;
337 socklen_t rcv_addr_len;
338 struct dccp_hdr *dhdr;
340 /*Memory for socket address*/
341 rcv_addr_len=sizeof(struct sockaddr_storage);
342 rcv_addr.gen=malloc(rcv_addr_len);
343 if(rcv_addr.gen==NULL){
344 dbgprintf(0,"Error: Can't Allocate Memory!\n");
349 rcv_addr_len=sizeof(struct sockaddr_storage);
350 if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,rcv_addr.gen,&rcv_addr_len))<0){
351 dbgprintf(0, "Error on receive from DCCP socket (%s)\n",strerror(errno));
354 if(rcv_addr.gen->sa_family!=ip_type){ //confirm IP type
355 dbgprintf(1, "DCCP packet on %s. Tossing.\n", (ip_type==AF_INET) ? "IPv4" : "IPv6");
360 if(rlen < sizeof(struct dccp_hdr)){ //check packet size
361 dbgprintf(1, "Packet smaller than possible DCCP packet received on DCCP socket\n");
367 if(rcv_addr.gen->sa_family==AF_INET){
369 if(memcmp(&rcv_addr.ipv4->sin_addr,&dest_addr.ipv4->sin_addr,
370 sizeof(dest_addr.ipv4->sin_addr))!=0){ //not from destination
371 dbgprintf(1,"DCCP packet from 3rd host\n");
377 if(memcmp(&rcv_addr.ipv6->sin6_addr, &dest_addr.ipv6->sin6_addr,
378 sizeof(dest_addr.ipv6->sin6_addr))!=0){ //not from destination
379 dbgprintf(1,"DCCP packet from 3rd host\n");
386 dhdr=(struct dccp_hdr*)rbuffer;
387 if(dhdr->dccph_sport!=htons(dest_port)){
388 dbgprintf(1,"DCCP packet with wrong Source Port\n");
392 if(dhdr->dccph_dport!=htons(dest_port)){
393 dbgprintf(1,"DCCP packet with wrong Destination Port\n");
399 if(dhdr->dccph_type==DCCP_PKT_RESET){
401 if(ip_type==AF_INET){
402 dbgprintf(0, "Got DCCP RESET from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
404 dbgprintf(0, "Got DCCP RESET from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
406 /*Nothing else to do*/
408 if(dhdr->dccph_type==DCCP_PKT_RESPONSE){
410 if(ip_type==AF_INET){
411 dbgprintf(0, "Got DCCP RESPONSE from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
413 dbgprintf(0, "Got DCCP RESPONSE from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
417 if(dhdr->dccph_type==DCCP_PKT_SYNC || dhdr->dccph_type==DCCP_PKT_SYNCACK){
419 if(ip_type==AF_INET){
420 dbgprintf(0, "Got DCCP SYNC from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
422 dbgprintf(0, "Got DCCP SYNC from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
430 void handleICMP4packet(int rcv_socket){
432 unsigned char rbuffer[rlen];
434 struct sockaddr_in rcv_addr;
435 socklen_t rcv_addr_len=sizeof(struct sockaddr_in);
436 struct icmphdr *icmp4;
439 if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,(struct sockaddr*)&rcv_addr,&rcv_addr_len))<0){
440 dbgprintf(0, "Error on receive from ICMP socket (%s)\n",strerror(errno));
443 if(rlen < sizeof(struct icmphdr)){ //check packet size
444 dbgprintf(1, "Packet smaller than possible ICMP packet!\n");
448 icmp4=(struct icmphdr*)rbuffer;
449 if(icmp4->type!=3 && icmp4->type!=11){ //check icmp types
450 dbgprintf(1, "Tossing ICMP packet of type %i\n", icmp4->type);
455 dbgprintf(0, "Got ICMPv4 type %i from %s\n", icmp4->type,
456 inet_ntop(ip_type, (void*)&rcv_addr.sin_addr, pbuf, 1000));
459 void handleICMP6packet(int rcv_socket){
461 unsigned char rbuffer[rlen];
463 struct sockaddr_in6 rcv_addr;
464 socklen_t rcv_addr_len=sizeof(struct sockaddr_in6);
465 struct icmp6_hdr *icmp6;
468 if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,(struct sockaddr*)&rcv_addr,&rcv_addr_len))<0){
469 dbgprintf(0, "Error on receive from ICMP socket (%s)\n",strerror(errno));
472 if(rlen < sizeof(struct icmp6_hdr)){ //check packet size
473 dbgprintf(1, "Packet smaller than possible ICMP packet!\n");
477 icmp6=(struct icmp6_hdr*)rbuffer;
478 if(icmp6->icmp6_type!=1 && icmp6->icmp6_type!=2 && icmp6->icmp6_type!=3
479 && icmp6->icmp6_type!=4){ //check icmp types
480 dbgprintf(1, "Tossing ICMP packet of type %i\n", icmp6->icmp6_type);
485 dbgprintf(0, "Got ICMPv6 type %i from %s\n", icmp6->icmp6_type,
486 inet_ntop(ip_type, (void*)&rcv_addr.sin6_addr, pbuf, 1000));
489 void buildRequestPacket(unsigned char* buffer, int *len){
490 struct dccp_hdr *dhdr;
491 struct dccp_hdr_ext *dhdre;
492 struct dccp_hdr_request *dhdrr;
493 struct iphdr* ip4hdr;
494 struct ip6_hdr* ip6hdr;
497 int dccp_hdr_len=sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext)+sizeof(struct dccp_hdr_request);
500 if(*len < dccp_hdr_len+sizeof(struct ip6_hdr)){
501 dbgprintf(0, "Error: Insufficient buffer space\n");
505 memset(buffer, 0, *len);
509 if(ip_type==AF_INET){
510 ip_hdr_len=sizeof(struct iphdr);
511 ip4hdr=(struct iphdr*)buffer;
512 ip4hdr->check=htons(0);
513 memcpy(&ip4hdr->daddr, &dest_addr.ipv4->sin_addr, sizeof(dest_addr.ipv4->sin_addr));
514 ip4hdr->frag_off=htons(0);
515 ip4hdr->id=htons(1);//first
517 ip4hdr->protocol=IPPROTO_DCCP;
518 memcpy(&ip4hdr->saddr, &src_addr.ipv4->sin_addr, sizeof(src_addr.ipv4->sin_addr));
520 ip4hdr->tot_len=htons(ip_hdr_len+dccp_hdr_len);
524 ip_hdr_len=sizeof(struct ip6_hdr);
525 ip6hdr=(struct ip6_hdr*)buffer;
526 memcpy(&ip6hdr->ip6_dst, &dest_addr.ipv6->sin6_addr, sizeof(dest_addr.ipv6->sin6_addr));
527 memcpy(&ip6hdr->ip6_src, &src_addr.ipv6->sin6_addr, sizeof(src_addr.ipv6->sin6_addr));
528 ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_flow=htonl(6<<28); //version, traffic class, flow label
529 ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_hlim=ttl;
530 ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_nxt=IPPROTO_DCCP;
531 ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_plen=htons(dccp_hdr_len);
535 dhdr=(struct dccp_hdr*)(buffer+ip_hdr_len);
536 dhdre=(struct dccp_hdr_ext*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr));
537 dhdrr=(struct dccp_hdr_request*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext));
539 dhdr->dccph_checksum=0;
541 dhdr->dccph_doff=dccp_hdr_len/4;
542 dhdr->dccph_dport=htons(dest_port);
543 dhdr->dccph_reserved=0;
544 dhdr->dccph_sport=htons(dest_port);
546 dhdr->dccph_type=DCCP_PKT_REQUEST;
547 dhdr->dccph_seq2=htonl(0); //Reserved if using 48 bit sequence numbers
548 dhdr->dccph_seq=htonl(0); //High 16bits of sequence number. Always make 0 for simplicity.
549 dhdre->dccph_seq_low=htonl(seq);
550 dhdrr->dccph_req_service= htonl(0x50455246);
553 if(ip_type==AF_INET){
554 dhdr->dccph_checksum=ipv4_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
555 (unsigned char*) &dest_addr.ipv4->sin_addr,
556 (unsigned char*)&src_addr.ipv4->sin_addr, IPPROTO_DCCP);
557 ip4hdr->check=ipv4_chksum(buffer,ip_hdr_len);
559 dhdr->dccph_checksum=ipv6_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
560 (unsigned char*) &dest_addr.ipv6->sin6_addr,
561 (unsigned char*)&src_addr.ipv6->sin6_addr, IPPROTO_DCCP);
563 *len=ip_hdr_len+dccp_hdr_len;
567 void updateRequestPacket(unsigned char* buffer, int *len){
568 struct dccp_hdr *dhdr;
569 struct dccp_hdr_ext *dhdre;
570 struct iphdr* ip4hdr;
573 int dccp_hdr_len=sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext)+sizeof(struct dccp_hdr_request);
578 if(ip_type==AF_INET){
579 ip_hdr_len=sizeof(struct iphdr);
580 ip4hdr=(struct iphdr*)buffer;
581 ip4hdr->check=htons(0);
582 tmp=ntohs(ip4hdr->id);
583 ip4hdr->id=htons(tmp+1);
585 ip_hdr_len=sizeof(struct ip6_hdr);
589 dhdr=(struct dccp_hdr*)(buffer+ip_hdr_len);
590 dhdre=(struct dccp_hdr_ext*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr));
591 dhdr->dccph_checksum=0;
592 tmp=ntohl(dhdre->dccph_seq_low);
593 dhdre->dccph_seq_low=htonl(tmp+1);
596 if(ip_type==AF_INET){
597 dhdr->dccph_checksum=ipv4_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
598 (unsigned char*) &dest_addr.ipv4->sin_addr,
599 (unsigned char*)&src_addr.ipv4->sin_addr, IPPROTO_DCCP);
600 ip4hdr->check=ipv4_chksum(buffer,ip_hdr_len);
602 dhdr->dccph_checksum=ipv6_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
603 (unsigned char*) &dest_addr.ipv6->sin6_addr,
604 (unsigned char*)&src_addr.ipv6->sin6_addr, IPPROTO_DCCP);
606 *len=ip_hdr_len+dccp_hdr_len;
610 /*Usage information for program*/
613 dbgprintf(0, "dccpping: [-d] [-6|-4] [-c count] [-p port] [-i interval] [-t ttl] [-S srcaddress] remote_host\n");
617 /*Program will probably be run setuid, so be extra careful*/
618 void sanitize_environment()
620 #if defined(_SVID_SOURCE) || defined(_XOPEN_SOURCE)
623 extern char **environ;
629 void dbgprintf(int level, const char *fmt, ...)
634 vfprintf(stderr, fmt, args);