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 handleICMPpacket(int rcv_socket);
55 void buildRequestPacket(unsigned char* buffer, int *len);
56 void updateRequestPacket(unsigned char* buffer, int *len);
57 void dbgprintf(int level, const char *fmt, ...);
58 void sanitize_environment();
62 /*Parse commandline options*/
63 int main(int argc, char *argv[])
70 sanitize_environment();
72 while ((c = getopt(argc, argv, "64c:p:i:dt:S:")) != -1) {
83 dbgprintf(0, "Error: count must be positive");
88 dest_port = atoi(optarg);
91 interval = (long)(atof(optarg) * 1000.0);
93 fprintf(stderr, "Invalid interval\n");
102 if (ttl < 1 || ttl > 255) {
103 fprintf(stderr, "Invalid TTL\n");
123 getAddresses(src, dst);
124 if(src_addr.gen==NULL || dest_addr.gen==NULL){
125 dbgprintf(0,"Error: Can't determine source or destination address\n");
136 void getAddresses(char *src, char* dst){
137 struct addrinfo hint;
138 struct addrinfo *dtmp, *stmp;
139 struct ifaddrs *temp, *cur;
140 struct sockaddr_in6* iv6;
144 /*Lookup destination Address*/
145 memset(&hint,0,sizeof(struct addrinfo));
146 hint.ai_family=ip_type;
147 hint.ai_flags=AI_V4MAPPED | AI_ADDRCONFIG;
149 if((err=getaddrinfo(dst,NULL,&hint,&dtmp))!=0){
150 dbgprintf(0,"Error: Couldn't lookup destination %s (%s)\n", dst, gai_strerror(err));
154 dbgprintf(0,"Error: Unknown Host %s\n", dst);
157 addrlen=dtmp->ai_addrlen;
158 hint.ai_family=ip_type=dtmp->ai_family;
159 dest_addr.gen=malloc(dtmp->ai_addrlen);
160 if(dest_addr.gen==NULL){
161 dbgprintf(0,"Error: Can't allocate Memory\n");
164 memcpy(dest_addr.gen,dtmp->ai_addr,dtmp->ai_addrlen);
168 /*Get a meaningful source address*/
170 /*Use Commandline arg*/
171 if((err=getaddrinfo(src,NULL,&hint,&stmp))!=0){
172 dbgprintf(0,"Error: Source Address %s is invalid (%s)\n", src, gai_strerror(err));
176 dbgprintf(0,"Error: Unknown Host %s\n", dst);
179 addrlen=stmp->ai_addrlen;
180 src_addr.gen=malloc(stmp->ai_addrlen);
181 if(src_addr.gen==NULL){
182 dbgprintf(0,"Error: Can't allocate Memory\n");
185 memcpy(src_addr.gen,stmp->ai_addr,stmp->ai_addrlen);
189 /*Guess a good source address*/
193 if(cur->ifa_addr==NULL || cur->ifa_addr->sa_family!=ip_type){ /*Not matching ipv4/ipv6 of dest*/
197 if(cur->ifa_flags & IFF_LOOPBACK){ /*Don't use loopback addresses*/
201 if(cur->ifa_addr!=NULL && cur->ifa_addr->sa_family==AF_INET6){
202 iv6=(struct sockaddr_in6*)cur->ifa_addr;
204 if(iv6->sin6_scope_id!=0){ /*Not globally valid address, if ipv6*/
210 src_addr.gen=malloc(sizeof(struct sockaddr_storage));
211 if(src_addr.gen==NULL){
212 dbgprintf(0,"Error: Can't allocate Memory\n");
215 src_addr.gen->sa_family=ip_type;
216 memcpy(src_addr.gen,cur->ifa_addr,addrlen);
225 /*Preform the ping functionality*/
231 unsigned char sbuffer[slen];
233 struct timeval timeout;
234 struct timeval t,delay, add;
238 rs=socket(ip_type, SOCK_RAW ,IPPROTO_RAW);
240 dbgprintf(0, "Error opening raw socket\n");
243 ds=socket(ip_type, SOCK_RAW ,IPPROTO_DCCP);
245 dbgprintf(0, "Error opening raw DCCP socket\n");
248 is=socket(ip_type,SOCK_RAW,IPPROTO_ICMP);
250 dbgprintf(0,"Error opening raw ICMP socket\n");
255 /*Build DCCP packet*/
256 buildRequestPacket(sbuffer,&slen);
257 if(ip_type==AF_INET){
258 addrlen=sizeof(struct sockaddr_in);
260 addrlen=sizeof(struct sockaddr_in6);
265 if(sendto(rs, &sbuffer, slen, MSG_DONTWAIT,(struct sockaddr*)dest_addr.gen,addrlen)<0){
266 dbgprintf(0,"Error: sendto failed\n");
268 if(ip_type==AF_INET){
269 dbgprintf(0, "Sending DCCP Request to %s\n",inet_ntop(ip_type, (void*)&dest_addr.ipv4->sin_addr, pbuf, 1000));
271 dbgprintf(0, "Sending DCCP Request to %s\n",inet_ntop(ip_type, (void*)&dest_addr.ipv6->sin6_addr, pbuf, 1000));
274 /*Use select to wait on packets or until interval has passed*/
275 add.tv_sec=interval/1000;
276 add.tv_usec=(interval%1000)*1000;
277 gettimeofday(&t,NULL);
278 timeradd(&t,&add,&delay);
282 while(timercmp(&t,&delay,<)){
283 timersub(&delay,&t,&timeout);
284 if(select(MAX(ds+1,is+1),&sel, NULL,NULL,&timeout)<0){
285 dbgprintf(0,"Select() error\n");
288 if(FD_ISSET(ds,&sel)){
289 /*Data on the DCCP socket*/
290 handleDCCPpacket(ds,rs);
293 if(FD_ISSET(is,&sel)){
294 /*Data on the ICMP socket*/
295 handleICMPpacket(is);
297 gettimeofday(&t,NULL);
309 updateRequestPacket(sbuffer,&slen);
317 void handleDCCPpacket(int rcv_socket, int send_socket){
319 unsigned char rbuffer[rlen];
321 ipaddr_ptr_t rcv_addr;
322 socklen_t rcv_addr_len;
323 struct dccp_hdr *dhdr;
325 /*Memory for socket address*/
326 rcv_addr_len=sizeof(struct sockaddr_storage);
327 rcv_addr.gen=malloc(rcv_addr_len);
328 if(rcv_addr.gen==NULL){
329 dbgprintf(0,"Error: Can't Allocate Memory!\n");
334 rcv_addr_len=sizeof(struct sockaddr_storage);
335 if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,rcv_addr.gen,&rcv_addr_len))<0){
336 dbgprintf(0, "Error on receive from DCCP socket (%s)\n",strerror(errno));
339 if(rcv_addr.gen->sa_family!=ip_type){ //confirm IP type
340 dbgprintf(1, "DCCP packet on %s. Tossing.\n", (ip_type==AF_INET) ? "IPv4" : "IPv6");
345 if(rlen < sizeof(struct dccp_hdr)){ //check packet size
346 dbgprintf(1, "Packet smaller than possible DCCP packet received on DCCP socket\n");
352 if(rcv_addr.gen->sa_family==AF_INET){
354 if(memcmp(&rcv_addr.ipv4->sin_addr,&dest_addr.ipv4->sin_addr,
355 sizeof(dest_addr.ipv4->sin_addr))!=0){ //not from destination
356 dbgprintf(1,"DCCP packet from 3rd host\n");
362 if(memcmp(&rcv_addr.ipv6->sin6_addr, &dest_addr.ipv6->sin6_addr,
363 sizeof(dest_addr.ipv6->sin6_addr))!=0){ //not from destination
364 dbgprintf(1,"DCCP packet from 3rd host\n");
371 dhdr=(struct dccp_hdr*)rbuffer;
372 if(dhdr->dccph_sport!=htons(dest_port)){
373 dbgprintf(1,"DCCP packet with wrong Source Port\n");
377 if(dhdr->dccph_dport!=htons(dest_port)){
378 dbgprintf(1,"DCCP packet with wrong Destination Port\n");
384 if(dhdr->dccph_type==DCCP_PKT_RESET){
386 if(ip_type==AF_INET){
387 dbgprintf(0, "Got DCCP RESET from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
389 dbgprintf(0, "Got DCCP RESET from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
391 /*Nothing else to do*/
393 if(dhdr->dccph_type==DCCP_PKT_RESPONSE){
395 if(ip_type==AF_INET){
396 dbgprintf(0, "Got DCCP RESPONSE from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
398 dbgprintf(0, "Got DCCP RESPONSE from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
402 if(dhdr->dccph_type==DCCP_PKT_SYNC || dhdr->dccph_type==DCCP_PKT_SYNCACK){
404 if(ip_type==AF_INET){
405 dbgprintf(0, "Got DCCP SYNC from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
407 dbgprintf(0, "Got DCCP SYNC from %s\n",inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
415 void handleICMPpacket(int rcv_socket){
417 unsigned char rbuffer[rlen];
419 ipaddr_ptr_t rcv_addr;
420 socklen_t rcv_addr_len;
421 struct icmphdr *icmp4;
422 struct icmp6_hdr *icmp6;
424 /*Memory for socket address*/
425 rcv_addr_len=sizeof(struct sockaddr_storage);
426 rcv_addr.gen=malloc(rcv_addr_len);
427 if(rcv_addr.gen==NULL){
428 dbgprintf(0,"Error: Can't Allocate Memory!\n");
433 if((rlen=recvfrom(rcv_socket, &rbuffer, 1000,0,rcv_addr.gen,&rcv_addr_len))<0){
434 dbgprintf(0, "Error on receive from ICMP socket (%s)\n",strerror(errno));
437 if(rcv_addr.gen->sa_family!=ip_type){ //confirm IP type
438 dbgprintf(1, "ICMP packet on %s. Tossing.\n", (ip_type==AF_INET) ? "IPv4" : "IPv6");
443 if(rcv_addr.gen->sa_family==AF_INET){
445 if(rlen < sizeof(struct icmphdr)){ //check packet size
446 dbgprintf(1, "Packet smaller than possible ICMP packet!\n");
451 icmp4=(struct icmphdr*)rbuffer;
452 if(icmp4->type!=3 && icmp4->type!=11){ //check icmp types
453 dbgprintf(1, "Tossing ICMP packet of type %i\n", icmp4->type);
459 dbgprintf(0, "Got ICMPv4 type %i from %s\n", icmp4->type,
460 inet_ntop(ip_type, (void*)&rcv_addr.ipv4->sin_addr, pbuf, 1000));
464 if(rlen < sizeof(struct icmp6_hdr)){ //check packet size
465 dbgprintf(1, "Packet smaller than possible ICMP packet!\n");
470 icmp6=(struct icmp6_hdr*)rbuffer;
471 if(icmp6->icmp6_type!=1 && icmp6->icmp6_type!=2 && icmp6->icmp6_type!=3
472 && icmp6->icmp6_type!=4){ //check icmp types
473 dbgprintf(1, "Tossing ICMP packet of type %i\n", icmp6->icmp6_type);
479 dbgprintf(0, "Got ICMPv6 type %i from %s\n", icmp6->icmp6_type,
480 inet_ntop(ip_type, (void*)&rcv_addr.ipv6->sin6_addr, pbuf, 1000));
486 void buildRequestPacket(unsigned char* buffer, int *len){
487 struct dccp_hdr *dhdr;
488 struct dccp_hdr_ext *dhdre;
489 struct dccp_hdr_request *dhdrr;
490 struct iphdr* ip4hdr;
491 struct ip6_hdr* ip6hdr;
494 int dccp_hdr_len=sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext)+sizeof(struct dccp_hdr_request);
497 if(*len < dccp_hdr_len+sizeof(struct ip6_hdr)){
498 dbgprintf(0, "Error: Insufficient buffer space\n");
502 memset(buffer, 0, *len);
506 if(ip_type==AF_INET){
507 ip_hdr_len=sizeof(struct iphdr);
508 ip4hdr=(struct iphdr*)buffer;
509 ip4hdr->check=htons(0);
510 memcpy(&ip4hdr->daddr, &dest_addr.ipv4->sin_addr, sizeof(dest_addr.ipv4->sin_addr));
511 ip4hdr->frag_off=htons(0);
512 ip4hdr->id=htons(1);//first
514 ip4hdr->protocol=IPPROTO_DCCP;
515 memcpy(&ip4hdr->saddr, &src_addr.ipv4->sin_addr, sizeof(src_addr.ipv4->sin_addr));
517 ip4hdr->tot_len=htons(ip_hdr_len+dccp_hdr_len);
521 ip_hdr_len=sizeof(struct ip6_hdr);
522 ip6hdr=(struct ip6_hdr*)buffer;
523 memcpy(&ip6hdr->ip6_dst, &dest_addr.ipv6->sin6_addr, sizeof(dest_addr.ipv6->sin6_addr));
524 memcpy(&ip6hdr->ip6_src, &src_addr.ipv6->sin6_addr, sizeof(src_addr.ipv6->sin6_addr));
525 ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_flow=htonl(6<<28); //version, traffic class, flow label
526 ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_hlim=ttl;
527 ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_nxt=IPPROTO_DCCP;
528 ip6hdr->ip6_ctlun.ip6_un1.ip6_un1_plen=htons(dccp_hdr_len);
532 dhdr=(struct dccp_hdr*)(buffer+ip_hdr_len);
533 dhdre=(struct dccp_hdr_ext*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr));
534 dhdrr=(struct dccp_hdr_request*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext));
536 dhdr->dccph_checksum=0;
538 dhdr->dccph_doff=dccp_hdr_len/4;
539 dhdr->dccph_dport=htons(dest_port);
540 dhdr->dccph_reserved=0;
541 dhdr->dccph_sport=htons(dest_port);
543 dhdr->dccph_type=DCCP_PKT_REQUEST;
544 dhdr->dccph_seq2=htonl(0); //Reserved if using 48 bit sequence numbers
545 dhdr->dccph_seq=htonl(0); //High 16bits of sequence number. Always make 0 for simplicity.
546 dhdre->dccph_seq_low=htonl(seq);
547 dhdrr->dccph_req_service= htonl(0x50455246);
550 if(ip_type==AF_INET){
551 dhdr->dccph_checksum=ipv4_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
552 (unsigned char*) &dest_addr.ipv4->sin_addr,
553 (unsigned char*)&src_addr.ipv4->sin_addr, IPPROTO_DCCP);
554 ip4hdr->check=ipv4_chksum(buffer,ip_hdr_len);
556 dhdr->dccph_checksum=ipv6_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
557 (unsigned char*) &dest_addr.ipv6->sin6_addr,
558 (unsigned char*)&src_addr.ipv6->sin6_addr, IPPROTO_DCCP);
560 *len=ip_hdr_len+dccp_hdr_len;
564 void updateRequestPacket(unsigned char* buffer, int *len){
565 struct dccp_hdr *dhdr;
566 struct dccp_hdr_ext *dhdre;
567 struct iphdr* ip4hdr;
570 int dccp_hdr_len=sizeof(struct dccp_hdr)+sizeof(struct dccp_hdr_ext)+sizeof(struct dccp_hdr_request);
575 if(ip_type==AF_INET){
576 ip_hdr_len=sizeof(struct iphdr);
577 ip4hdr=(struct iphdr*)buffer;
578 ip4hdr->check=htons(0);
579 tmp=ntohs(ip4hdr->id);
580 ip4hdr->id=htons(tmp+1);
582 ip_hdr_len=sizeof(struct ip6_hdr);
586 dhdr=(struct dccp_hdr*)(buffer+ip_hdr_len);
587 dhdre=(struct dccp_hdr_ext*)(buffer+ip_hdr_len+sizeof(struct dccp_hdr));
588 dhdr->dccph_checksum=0;
589 tmp=ntohl(dhdre->dccph_seq_low);
590 dhdre->dccph_seq_low=htonl(tmp+1);
593 if(ip_type==AF_INET){
594 dhdr->dccph_checksum=ipv4_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
595 (unsigned char*) &dest_addr.ipv4->sin_addr,
596 (unsigned char*)&src_addr.ipv4->sin_addr, IPPROTO_DCCP);
597 ip4hdr->check=ipv4_chksum(buffer,ip_hdr_len);
599 dhdr->dccph_checksum=ipv6_pseudohdr_chksum((buffer+ip_hdr_len), dccp_hdr_len,
600 (unsigned char*) &dest_addr.ipv6->sin6_addr,
601 (unsigned char*)&src_addr.ipv6->sin6_addr, IPPROTO_DCCP);
603 *len=ip_hdr_len+dccp_hdr_len;
607 /*Usage information for program*/
610 dbgprintf(0, "dccpping: [-d] [-6|-4] [-c count] [-p port] [-i interval] [-t ttl] [-S srcaddress] remote_host\n");
614 /*Program will probably be run setuid, so be extra careful*/
615 void sanitize_environment()
617 #if defined(_SVID_SOURCE) || defined(_XOPEN_SOURCE)
620 extern char **environ;
626 void dbgprintf(int level, const char *fmt, ...)
631 vfprintf(stderr, fmt, args);