2 * Copyright (c) 1982, 1986, 1988, 1990, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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9 * notice, this list of conditions and the following disclaimer.
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13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
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21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * @(#)udp_usrreq.c 8.4 (Berkeley) 1/21/94
34 * udp_usrreq.c,v 1.4 1994/10/02 17:48:45 phk Exp
38 * Changes and additions relating to SLiRP
39 * Copyright (c) 1995 Danny Gasparovski.
41 * Please read the file COPYRIGHT for the
42 * terms and conditions of the copyright.
49 struct udpstat udpstat;
54 static u_int8_t udp_tos(struct socket *so);
55 static void udp_emu(struct socket *so, struct mbuf *m);
58 * UDP protocol implementation.
59 * Per RFC 768, August, 1980.
64 #define UDPCKSUM 0 /* XXX */
67 struct socket *udp_last_so = &udb;
72 udb.so_next = udb.so_prev = &udb;
74 /* m->m_data points at ip packet header
75 * m->m_len length ip packet
76 * ip->ip_len length data (IPDU)
80 register struct mbuf *m;
83 register struct ip *ip;
84 register struct udphdr *uh;
85 /* struct mbuf *opts = 0;*/
90 DEBUG_CALL("udp_input");
91 DEBUG_ARG("m = %lx", (long)m);
92 DEBUG_ARG("iphlen = %d", iphlen);
94 STAT(udpstat.udps_ipackets++);
97 * Strip IP options, if any; should skip this,
98 * make available to user, and use on returned packets,
99 * but we don't yet have a way to check the checksum
100 * with options still present.
102 if(iphlen > sizeof(struct ip)) {
103 ip_stripoptions(m, (struct mbuf *)0);
104 iphlen = sizeof(struct ip);
108 * Get IP and UDP header together in first mbuf.
110 ip = mtod(m, struct ip *);
111 uh = (struct udphdr *)((caddr_t)ip + iphlen);
114 * Make mbuf data length reflect UDP length.
115 * If not enough data to reflect UDP length, drop.
117 len = ntohs((u_int16_t)uh->uh_ulen);
119 if (ip->ip_len != len) {
120 if (len > ip->ip_len) {
121 STAT(udpstat.udps_badlen++);
124 m_adj(m, len - ip->ip_len);
129 * Save a copy of the IP header in case we want restore it
130 * for sending an ICMP error message in response.
133 save_ip.ip_len+= iphlen; /* tcp_input subtracts this */
136 * Checksum extended UDP header and data.
138 if (UDPCKSUM && uh->uh_sum) {
139 ((struct ipovly *)ip)->ih_next = 0;
140 ((struct ipovly *)ip)->ih_prev = 0;
141 ((struct ipovly *)ip)->ih_x1 = 0;
142 ((struct ipovly *)ip)->ih_len = uh->uh_ulen;
143 /* keep uh_sum for ICMP reply
144 * uh->uh_sum = cksum(m, len + sizeof (struct ip));
147 if(cksum(m, len + sizeof(struct ip))) {
148 STAT(udpstat.udps_badsum++);
156 if (ntohs(uh->uh_dport) == BOOTP_SERVER) {
164 if (ntohs(uh->uh_dport) == TFTP_SERVER) {
170 * Locate pcb for datagram.
173 if (so->so_lport != uh->uh_sport ||
174 so->so_laddr.s_addr != ip->ip_src.s_addr) {
177 for (tmp = udb.so_next; tmp != &udb; tmp = tmp->so_next) {
178 if (tmp->so_lport == uh->uh_sport &&
179 tmp->so_laddr.s_addr == ip->ip_src.s_addr) {
180 tmp->so_faddr.s_addr = ip->ip_dst.s_addr;
181 tmp->so_fport = uh->uh_dport;
189 STAT(udpstat.udpps_pcbcachemiss++);
196 * If there's no socket for this packet,
199 if ((so = socreate()) == NULL) goto bad;
200 if(udp_attach(so) == -1) {
201 DEBUG_MISC((dfd," udp_attach errno = %d-%s\n",
202 errno,strerror(errno)));
210 /* udp_last_so = so; */
211 so->so_laddr = ip->ip_src;
212 so->so_lport = uh->uh_sport;
214 if ((so->so_iptos = udp_tos(so)) == 0)
215 so->so_iptos = ip->ip_tos;
218 * XXXXX Here, check if it's in udpexec_list,
219 * and if it is, do the fork_exec() etc.
223 so->so_faddr = ip->ip_dst; /* XXX */
224 so->so_fport = uh->uh_dport; /* XXX */
226 iphlen += sizeof(struct udphdr);
231 * Now we sendto() the packet.
236 if(sosendto(so,m) == -1) {
240 DEBUG_MISC((dfd,"udp tx errno = %d-%s\n",errno,strerror(errno)));
241 icmp_error(m, ICMP_UNREACH,ICMP_UNREACH_NET, 0,strerror(errno));
244 m_free(so->so_m); /* used for ICMP if error on sorecvfrom */
246 /* restore the orig mbuf packet */
250 so->so_m=m; /* ICMP backup */
255 /* if (opts) m_freem(opts); */
259 int udp_output2(struct socket *so, struct mbuf *m,
260 struct sockaddr_in *saddr, struct sockaddr_in *daddr,
263 register struct udpiphdr *ui;
266 DEBUG_CALL("udp_output");
267 DEBUG_ARG("so = %lx", (long)so);
268 DEBUG_ARG("m = %lx", (long)m);
269 DEBUG_ARG("saddr = %lx", (long)saddr->sin_addr.s_addr);
270 DEBUG_ARG("daddr = %lx", (long)daddr->sin_addr.s_addr);
275 m->m_data -= sizeof(struct udpiphdr);
276 m->m_len += sizeof(struct udpiphdr);
279 * Fill in mbuf with extended UDP header
280 * and addresses and length put into network format.
282 ui = mtod(m, struct udpiphdr *);
283 ui->ui_next = ui->ui_prev = 0;
285 ui->ui_pr = IPPROTO_UDP;
286 ui->ui_len = htons(m->m_len - sizeof(struct ip)); /* + sizeof (struct udphdr)); */
287 /* XXXXX Check for from-one-location sockets, or from-any-location sockets */
288 ui->ui_src = saddr->sin_addr;
289 ui->ui_dst = daddr->sin_addr;
290 ui->ui_sport = saddr->sin_port;
291 ui->ui_dport = daddr->sin_port;
292 ui->ui_ulen = ui->ui_len;
295 * Stuff checksum and output datagram.
299 if ((ui->ui_sum = cksum(m, /* sizeof (struct udpiphdr) + */ m->m_len)) == 0)
302 ((struct ip *)ui)->ip_len = m->m_len;
304 ((struct ip *)ui)->ip_ttl = IPDEFTTL;
305 ((struct ip *)ui)->ip_tos = iptos;
307 STAT(udpstat.udps_opackets++);
309 error = ip_output(so, m);
314 int udp_output(struct socket *so, struct mbuf *m,
315 struct sockaddr_in *addr)
318 struct sockaddr_in saddr, daddr;
321 if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr &&
322 addr->sin_addr.s_addr == htonl(0x7f000001)) {
323 saddr.sin_addr.s_addr = so->so_faddr.s_addr;
324 if ((so->so_faddr.s_addr & htonl(0x000000ff)) == htonl(0xff))
325 saddr.sin_addr.s_addr = alias_addr.s_addr;
327 daddr.sin_addr = so->so_laddr;
328 daddr.sin_port = so->so_lport;
330 return udp_output2(so, m, &saddr, &daddr, so->so_iptos);
337 struct sockaddr_in addr;
339 if((so->s = socket(AF_INET,SOCK_DGRAM,0)) != -1) {
341 * Here, we bind() the socket. Although not really needed
342 * (sendto() on an unbound socket will bind it), it's done
343 * here so that emulation of ytalk etc. don't have to do it
345 addr.sin_family = AF_INET;
347 addr.sin_addr.s_addr = INADDR_ANY;
348 if(bind(so->s, (struct sockaddr *)&addr, sizeof(addr))<0) {
353 WSASetLastError(lasterrno);
358 /* success, insert in queue */
359 so->so_expire = curtime + SO_EXPIRE;
371 /* if (so->so_m) m_free(so->so_m); done by sofree */
376 static const struct tos_t udptos[] = {
377 {0, 53, IPTOS_LOWDELAY, 0}, /* DNS */
378 {517, 517, IPTOS_LOWDELAY, EMU_TALK}, /* talk */
379 {518, 518, IPTOS_LOWDELAY, EMU_NTALK}, /* ntalk */
380 {0, 7648, IPTOS_LOWDELAY, EMU_CUSEEME}, /* Cu-Seeme */
385 udp_tos(struct socket *so)
389 while(udptos[i].tos) {
390 if ((udptos[i].fport && ntohs(so->so_fport) == udptos[i].fport) ||
391 (udptos[i].lport && ntohs(so->so_lport) == udptos[i].lport)) {
392 so->so_emu = udptos[i].emu;
393 return udptos[i].tos;
406 * Here, talk/ytalk/ntalk requests must be emulated
409 udp_emu(struct socket *so, struct mbuf *m)
411 struct sockaddr_in addr;
412 int addrlen = sizeof(addr);
416 char buff[sizeof(CTL_MSG)];
419 struct talk_request {
420 struct talk_request *next;
421 struct socket *udp_so;
422 struct socket *tcp_so;
425 static struct talk_request *req_tbl = 0;
430 uint16_t d_family; // destination family
431 uint16_t d_port; // destination port
432 uint32_t d_addr; // destination address
433 uint16_t s_family; // source family
434 uint16_t s_port; // source port
435 uint32_t so_addr; // source address
436 uint32_t seqn; // sequence number
437 uint16_t message; // message
438 uint16_t data_type; // data type
439 uint16_t pkt_len; // packet length
448 * Talk emulation. We always change the ctl_addr to get
449 * some answers from the daemon. When an ANNOUNCE comes,
450 * we send LEAVE_INVITE to the local daemons. Also when a
451 * DELETE comes, we send copies to the local daemons.
453 if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0)
456 #define IS_OLD (so->so_emu == EMU_TALK)
458 #define COPY_MSG(dest, src) { dest->type = src->type; \
459 dest->id_num = src->id_num; \
460 dest->pid = src->pid; \
461 dest->addr = src->addr; \
462 dest->ctl_addr = src->ctl_addr; \
463 memcpy(&dest->l_name, &src->l_name, NAME_SIZE_OLD); \
464 memcpy(&dest->r_name, &src->r_name, NAME_SIZE_OLD); \
465 memcpy(&dest->r_tty, &src->r_tty, TTY_SIZE); }
467 #define OTOSIN(ptr, field) ((struct sockaddr_in *)&ptr->field)
468 /* old_sockaddr to sockaddr_in */
471 if (IS_OLD) { /* old talk */
472 omsg = mtod(m, CTL_MSG_OLD*);
473 nmsg = (CTL_MSG *) buff;
475 OTOSIN(omsg, ctl_addr)->sin_port = addr.sin_port;
476 OTOSIN(omsg, ctl_addr)->sin_addr = our_addr;
477 strncpy(omsg->l_name, getlogin(), NAME_SIZE_OLD);
478 } else { /* new talk */
479 omsg = (CTL_MSG_OLD *) buff;
480 nmsg = mtod(m, CTL_MSG *);
482 OTOSIN(nmsg, ctl_addr)->sin_port = addr.sin_port;
483 OTOSIN(nmsg, ctl_addr)->sin_addr = our_addr;
484 strncpy(nmsg->l_name, getlogin(), NAME_SIZE_OLD);
488 return; /* for LOOK_UP this is enough */
490 if (IS_OLD) { /* make a copy of the message */
491 COPY_MSG(nmsg, omsg);
495 COPY_MSG(omsg, nmsg);
498 * If if is an ANNOUNCE message, we go through the
499 * request table to see if a tcp port has already
500 * been redirected for this socket. If not, we solisten()
501 * a new socket and add this entry to the table.
502 * The port number of the tcp socket and our IP
503 * are put to the addr field of the message structures.
504 * Then a LEAVE_INVITE is sent to both local daemon
505 * ports, 517 and 518. This is why we have two copies
506 * of the message, one in old talk and one in new talk
510 if (type == ANNOUNCE) {
514 for(req = req_tbl; req; req = req->next)
515 if (so == req->udp_so)
516 break; /* found it */
518 if (!req) { /* no entry for so, create new */
519 req = (struct talk_request *)
520 malloc(sizeof(struct talk_request));
522 req->tcp_so = solisten(0,
523 OTOSIN(omsg, addr)->sin_addr.s_addr,
524 OTOSIN(omsg, addr)->sin_port,
530 /* replace port number in addr field */
531 addrlen = sizeof(addr);
532 getsockname(req->tcp_so->s,
533 (struct sockaddr *) &addr,
535 OTOSIN(omsg, addr)->sin_port = addr.sin_port;
536 OTOSIN(omsg, addr)->sin_addr = our_addr;
537 OTOSIN(nmsg, addr)->sin_port = addr.sin_port;
538 OTOSIN(nmsg, addr)->sin_addr = our_addr;
540 /* send LEAVE_INVITEs */
541 temp_port = OTOSIN(omsg, ctl_addr)->sin_port;
542 OTOSIN(omsg, ctl_addr)->sin_port = 0;
543 OTOSIN(nmsg, ctl_addr)->sin_port = 0;
544 omsg->type = nmsg->type = LEAVE_INVITE;
546 s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
547 addr.sin_addr = our_addr;
548 addr.sin_family = AF_INET;
549 addr.sin_port = htons(517);
550 sendto(s, (char *)omsg, sizeof(*omsg), 0,
551 (struct sockaddr *)&addr, sizeof(addr));
552 addr.sin_port = htons(518);
553 sendto(s, (char *)nmsg, sizeof(*nmsg), 0,
554 (struct sockaddr *) &addr, sizeof(addr));
557 omsg->type = nmsg->type = ANNOUNCE;
558 OTOSIN(omsg, ctl_addr)->sin_port = temp_port;
559 OTOSIN(nmsg, ctl_addr)->sin_port = temp_port;
563 * If it is a DELETE message, we send a copy to the
564 * local daemons. Then we delete the entry corresponding
565 * to our socket from the request table.
568 if (type == DELETE) {
569 struct talk_request *temp_req, *req_next;
573 temp_port = OTOSIN(omsg, ctl_addr)->sin_port;
574 OTOSIN(omsg, ctl_addr)->sin_port = 0;
575 OTOSIN(nmsg, ctl_addr)->sin_port = 0;
577 s = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
578 addr.sin_addr = our_addr;
579 addr.sin_family = AF_INET;
580 addr.sin_port = htons(517);
581 sendto(s, (char *)omsg, sizeof(*omsg), 0,
582 (struct sockaddr *)&addr, sizeof(addr));
583 addr.sin_port = htons(518);
584 sendto(s, (char *)nmsg, sizeof(*nmsg), 0,
585 (struct sockaddr *)&addr, sizeof(addr));
588 OTOSIN(omsg, ctl_addr)->sin_port = temp_port;
589 OTOSIN(nmsg, ctl_addr)->sin_port = temp_port;
591 /* delete table entry */
592 if (so == req_tbl->udp_so) {
594 req_tbl = req_tbl->next;
598 for(req = req_tbl->next; req; req = req_next) {
599 req_next = req->next;
600 if (so == req->udp_so) {
601 temp_req->next = req_next;
617 * Cu-SeeMe emulation.
618 * Hopefully the packet is more that 16 bytes long. We don't
619 * do any other tests, just replace the address and port
622 if (m->m_len >= sizeof (*cu_head)) {
623 if (getsockname(so->s, (struct sockaddr *)&addr, &addrlen) < 0)
625 cu_head = mtod(m, struct cu_header *);
626 cu_head->s_port = addr.sin_port;
627 cu_head->so_addr = our_addr.s_addr;
635 udp_listen(port, laddr, lport, flags)
641 struct sockaddr_in addr;
643 int addrlen = sizeof(struct sockaddr_in), opt = 1;
645 if ((so = socreate()) == NULL) {
649 so->s = socket(AF_INET,SOCK_DGRAM,0);
650 so->so_expire = curtime + SO_EXPIRE;
653 addr.sin_family = AF_INET;
654 addr.sin_addr.s_addr = INADDR_ANY;
655 addr.sin_port = port;
657 if (bind(so->s,(struct sockaddr *)&addr, addrlen) < 0) {
661 setsockopt(so->s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int));
662 /* setsockopt(so->s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int)); */
664 getsockname(so->s,(struct sockaddr *)&addr,&addrlen);
665 so->so_fport = addr.sin_port;
666 if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
667 so->so_faddr = alias_addr;
669 so->so_faddr = addr.sin_addr;
671 so->so_lport = lport;
672 so->so_laddr.s_addr = laddr;
673 if (flags != SS_FACCEPTONCE)
676 so->so_state = SS_ISFCONNECTED;