xref: /freebsd/sys/netinet/in_pcb.c (revision 0ea3482342b4d7d6e71f3007ce4dafe445c639fd)
1 /*
2  * Copyright (c) 1982, 1986, 1991, 1993, 1995
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
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
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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
31  * SUCH DAMAGE.
32  *
33  *	@(#)in_pcb.c	8.4 (Berkeley) 5/24/95
34  *	$Id: in_pcb.c,v 1.13 1995/09/21 17:55:49 wollman Exp $
35  */
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/malloc.h>
40 #include <sys/mbuf.h>
41 #include <sys/protosw.h>
42 #include <sys/socket.h>
43 #include <sys/socketvar.h>
44 #include <sys/ioctl.h>
45 #include <sys/errno.h>
46 #include <sys/time.h>
47 #include <sys/proc.h>
48 #include <sys/queue.h>
49 
50 #include <net/if.h>
51 #include <net/route.h>
52 
53 #include <netinet/in.h>
54 #include <netinet/in_systm.h>
55 #include <netinet/ip.h>
56 #include <netinet/in_pcb.h>
57 #include <netinet/in_var.h>
58 #include <netinet/ip_var.h>
59 
60 struct	in_addr zeroin_addr;
61 
62 int
63 in_pcballoc(so, pcbinfo)
64 	struct socket *so;
65 	struct inpcbinfo *pcbinfo;
66 {
67 	register struct inpcb *inp;
68 	int s;
69 
70 	MALLOC(inp, struct inpcb *, sizeof(*inp), M_PCB, M_NOWAIT);
71 	if (inp == NULL)
72 		return (ENOBUFS);
73 	bzero((caddr_t)inp, sizeof(*inp));
74 	inp->inp_pcbinfo = pcbinfo;
75 	inp->inp_socket = so;
76 	s = splnet();
77 	LIST_INSERT_HEAD(pcbinfo->listhead, inp, inp_list);
78 	in_pcbinshash(inp);
79 	splx(s);
80 	so->so_pcb = (caddr_t)inp;
81 	return (0);
82 }
83 
84 int
85 in_pcbbind(inp, nam)
86 	register struct inpcb *inp;
87 	struct mbuf *nam;
88 {
89 	register struct socket *so = inp->inp_socket;
90 	struct inpcbhead *head = inp->inp_pcbinfo->listhead;
91 	unsigned short *lastport = &inp->inp_pcbinfo->lastport;
92 	struct sockaddr_in *sin;
93 	struct proc *p = curproc;		/* XXX */
94 	u_short lport = 0;
95 	int wild = 0, reuseport = (so->so_options & SO_REUSEPORT);
96 	int error;
97 
98 	if (in_ifaddr == 0)
99 		return (EADDRNOTAVAIL);
100 	if (inp->inp_lport || inp->inp_laddr.s_addr != INADDR_ANY)
101 		return (EINVAL);
102 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0 &&
103 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
104 	     (so->so_options & SO_ACCEPTCONN) == 0))
105 		wild = INPLOOKUP_WILDCARD;
106 	if (nam) {
107 		sin = mtod(nam, struct sockaddr_in *);
108 		if (nam->m_len != sizeof (*sin))
109 			return (EINVAL);
110 #ifdef notdef
111 		/*
112 		 * We should check the family, but old programs
113 		 * incorrectly fail to initialize it.
114 		 */
115 		if (sin->sin_family != AF_INET)
116 			return (EAFNOSUPPORT);
117 #endif
118 		lport = sin->sin_port;
119 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) {
120 			/*
121 			 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
122 			 * allow complete duplication of binding if
123 			 * SO_REUSEPORT is set, or if SO_REUSEADDR is set
124 			 * and a multicast address is bound on both
125 			 * new and duplicated sockets.
126 			 */
127 			if (so->so_options & SO_REUSEADDR)
128 				reuseport = SO_REUSEADDR|SO_REUSEPORT;
129 		} else if (sin->sin_addr.s_addr != INADDR_ANY) {
130 			sin->sin_port = 0;		/* yech... */
131 			if (ifa_ifwithaddr((struct sockaddr *)sin) == 0)
132 				return (EADDRNOTAVAIL);
133 		}
134 		if (lport) {
135 			struct inpcb *t;
136 
137 			/* GROSS */
138 			if (ntohs(lport) < IPPORT_RESERVED &&
139 			    (error = suser(p->p_ucred, &p->p_acflag)))
140 				return (EACCES);
141 			t = in_pcblookup(head, zeroin_addr, 0,
142 			    sin->sin_addr, lport, wild);
143 			if (t && (reuseport & t->inp_socket->so_options) == 0)
144 				return (EADDRINUSE);
145 		}
146 		inp->inp_laddr = sin->sin_addr;
147 	}
148 	if (lport == 0)
149 		do {
150 			++*lastport;
151 			if (*lastport < IPPORT_RESERVED ||
152 			    *lastport > IPPORT_USERRESERVED)
153 				*lastport = IPPORT_RESERVED;
154 			lport = htons(*lastport);
155 		} while (in_pcblookup(head,
156 			    zeroin_addr, 0, inp->inp_laddr, lport, wild));
157 	inp->inp_lport = lport;
158 	in_pcbrehash(inp);
159 	return (0);
160 }
161 
162 /*
163  *   Transform old in_pcbconnect() into an inner subroutine for new
164  *   in_pcbconnect(): Do some validity-checking on the remote
165  *   address (in mbuf 'nam') and then determine local host address
166  *   (i.e., which interface) to use to access that remote host.
167  *
168  *   This preserves definition of in_pcbconnect(), while supporting a
169  *   slightly different version for T/TCP.  (This is more than
170  *   a bit of a kludge, but cleaning up the internal interfaces would
171  *   have forced minor changes in every protocol).
172  */
173 
174 int
175 in_pcbladdr(inp, nam, plocal_sin)
176 	register struct inpcb *inp;
177 	struct mbuf *nam;
178 	struct sockaddr_in **plocal_sin;
179 {
180 	struct in_ifaddr *ia;
181 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
182 
183 	if (nam->m_len != sizeof (*sin))
184 		return (EINVAL);
185 	if (sin->sin_family != AF_INET)
186 		return (EAFNOSUPPORT);
187 	if (sin->sin_port == 0)
188 		return (EADDRNOTAVAIL);
189 	if (in_ifaddr) {
190 		/*
191 		 * If the destination address is INADDR_ANY,
192 		 * use the primary local address.
193 		 * If the supplied address is INADDR_BROADCAST,
194 		 * and the primary interface supports broadcast,
195 		 * choose the broadcast address for that interface.
196 		 */
197 #define	satosin(sa)	((struct sockaddr_in *)(sa))
198 #define sintosa(sin)	((struct sockaddr *)(sin))
199 #define ifatoia(ifa)	((struct in_ifaddr *)(ifa))
200 		if (sin->sin_addr.s_addr == INADDR_ANY)
201 		    sin->sin_addr = IA_SIN(in_ifaddr)->sin_addr;
202 		else if (sin->sin_addr.s_addr == (u_long)INADDR_BROADCAST &&
203 		  (in_ifaddr->ia_ifp->if_flags & IFF_BROADCAST))
204 		    sin->sin_addr = satosin(&in_ifaddr->ia_broadaddr)->sin_addr;
205 	}
206 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
207 		register struct route *ro;
208 
209 		ia = (struct in_ifaddr *)0;
210 		/*
211 		 * If route is known or can be allocated now,
212 		 * our src addr is taken from the i/f, else punt.
213 		 */
214 		ro = &inp->inp_route;
215 		if (ro->ro_rt &&
216 		    (satosin(&ro->ro_dst)->sin_addr.s_addr !=
217 			sin->sin_addr.s_addr ||
218 		    inp->inp_socket->so_options & SO_DONTROUTE)) {
219 			RTFREE(ro->ro_rt);
220 			ro->ro_rt = (struct rtentry *)0;
221 		}
222 		if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0 && /*XXX*/
223 		    (ro->ro_rt == (struct rtentry *)0 ||
224 		    ro->ro_rt->rt_ifp == (struct ifnet *)0)) {
225 			/* No route yet, so try to acquire one */
226 			ro->ro_dst.sa_family = AF_INET;
227 			ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
228 			((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
229 				sin->sin_addr;
230 			rtalloc(ro);
231 		}
232 		/*
233 		 * If we found a route, use the address
234 		 * corresponding to the outgoing interface
235 		 * unless it is the loopback (in case a route
236 		 * to our address on another net goes to loopback).
237 		 */
238 		if (ro->ro_rt && !(ro->ro_rt->rt_ifp->if_flags & IFF_LOOPBACK))
239 			ia = ifatoia(ro->ro_rt->rt_ifa);
240 		if (ia == 0) {
241 			u_short fport = sin->sin_port;
242 
243 			sin->sin_port = 0;
244 			ia = ifatoia(ifa_ifwithdstaddr(sintosa(sin)));
245 			if (ia == 0)
246 				ia = ifatoia(ifa_ifwithnet(sintosa(sin)));
247 			sin->sin_port = fport;
248 			if (ia == 0)
249 				ia = in_ifaddr;
250 			if (ia == 0)
251 				return (EADDRNOTAVAIL);
252 		}
253 		/*
254 		 * If the destination address is multicast and an outgoing
255 		 * interface has been set as a multicast option, use the
256 		 * address of that interface as our source address.
257 		 */
258 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr)) &&
259 		    inp->inp_moptions != NULL) {
260 			struct ip_moptions *imo;
261 			struct ifnet *ifp;
262 
263 			imo = inp->inp_moptions;
264 			if (imo->imo_multicast_ifp != NULL) {
265 				ifp = imo->imo_multicast_ifp;
266 				for (ia = in_ifaddr; ia; ia = ia->ia_next)
267 					if (ia->ia_ifp == ifp)
268 						break;
269 				if (ia == 0)
270 					return (EADDRNOTAVAIL);
271 			}
272 		}
273 	/*
274 	 * Don't do pcblookup call here; return interface in plocal_sin
275 	 * and exit to caller, that will do the lookup.
276 	 */
277 		*plocal_sin = &ia->ia_addr;
278 
279 	}
280 	return(0);
281 }
282 
283 /*
284  * Outer subroutine:
285  * Connect from a socket to a specified address.
286  * Both address and port must be specified in argument sin.
287  * If don't have a local address for this socket yet,
288  * then pick one.
289  */
290 int
291 in_pcbconnect(inp, nam)
292 	register struct inpcb *inp;
293 	struct mbuf *nam;
294 {
295 	struct sockaddr_in *ifaddr;
296 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
297 	int error;
298 
299 	/*
300 	 *   Call inner routine, to assign local interface address.
301 	 */
302 	if (error = in_pcbladdr(inp, nam, &ifaddr))
303 		return(error);
304 
305 	if (in_pcblookuphash(inp->inp_pcbinfo, sin->sin_addr, sin->sin_port,
306 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
307 	    inp->inp_lport) != NULL)
308 		return (EADDRINUSE);
309 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
310 		if (inp->inp_lport == 0)
311 			(void)in_pcbbind(inp, (struct mbuf *)0);
312 		inp->inp_laddr = ifaddr->sin_addr;
313 	}
314 	inp->inp_faddr = sin->sin_addr;
315 	inp->inp_fport = sin->sin_port;
316 	in_pcbrehash(inp);
317 	return (0);
318 }
319 
320 void
321 in_pcbdisconnect(inp)
322 	struct inpcb *inp;
323 {
324 
325 	inp->inp_faddr.s_addr = INADDR_ANY;
326 	inp->inp_fport = 0;
327 	in_pcbrehash(inp);
328 	if (inp->inp_socket->so_state & SS_NOFDREF)
329 		in_pcbdetach(inp);
330 }
331 
332 void
333 in_pcbdetach(inp)
334 	struct inpcb *inp;
335 {
336 	struct socket *so = inp->inp_socket;
337 	int s;
338 
339 	so->so_pcb = 0;
340 	sofree(so);
341 	if (inp->inp_options)
342 		(void)m_free(inp->inp_options);
343 	if (inp->inp_route.ro_rt)
344 		rtfree(inp->inp_route.ro_rt);
345 	ip_freemoptions(inp->inp_moptions);
346 	s = splnet();
347 	LIST_REMOVE(inp, inp_hash);
348 	LIST_REMOVE(inp, inp_list);
349 	splx(s);
350 	FREE(inp, M_PCB);
351 }
352 
353 void
354 in_setsockaddr(inp, nam)
355 	register struct inpcb *inp;
356 	struct mbuf *nam;
357 {
358 	register struct sockaddr_in *sin;
359 
360 	nam->m_len = sizeof (*sin);
361 	sin = mtod(nam, struct sockaddr_in *);
362 	bzero((caddr_t)sin, sizeof (*sin));
363 	sin->sin_family = AF_INET;
364 	sin->sin_len = sizeof(*sin);
365 	sin->sin_port = inp->inp_lport;
366 	sin->sin_addr = inp->inp_laddr;
367 }
368 
369 void
370 in_setpeeraddr(inp, nam)
371 	struct inpcb *inp;
372 	struct mbuf *nam;
373 {
374 	register struct sockaddr_in *sin;
375 
376 	nam->m_len = sizeof (*sin);
377 	sin = mtod(nam, struct sockaddr_in *);
378 	bzero((caddr_t)sin, sizeof (*sin));
379 	sin->sin_family = AF_INET;
380 	sin->sin_len = sizeof(*sin);
381 	sin->sin_port = inp->inp_fport;
382 	sin->sin_addr = inp->inp_faddr;
383 }
384 
385 /*
386  * Pass some notification to all connections of a protocol
387  * associated with address dst.  The local address and/or port numbers
388  * may be specified to limit the search.  The "usual action" will be
389  * taken, depending on the ctlinput cmd.  The caller must filter any
390  * cmds that are uninteresting (e.g., no error in the map).
391  * Call the protocol specific routine (if any) to report
392  * any errors for each matching socket.
393  *
394  * Must be called at splnet.
395  */
396 void
397 in_pcbnotify(head, dst, fport_arg, laddr, lport_arg, cmd, notify)
398 	struct inpcbhead *head;
399 	struct sockaddr *dst;
400 	u_int fport_arg, lport_arg;
401 	struct in_addr laddr;
402 	int cmd;
403 	void (*notify) __P((struct inpcb *, int));
404 {
405 	register struct inpcb *inp, *oinp;
406 	struct in_addr faddr;
407 	u_short fport = fport_arg, lport = lport_arg;
408 	int errno, s;
409 
410 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET)
411 		return;
412 	faddr = ((struct sockaddr_in *)dst)->sin_addr;
413 	if (faddr.s_addr == INADDR_ANY)
414 		return;
415 
416 	/*
417 	 * Redirects go to all references to the destination,
418 	 * and use in_rtchange to invalidate the route cache.
419 	 * Dead host indications: notify all references to the destination.
420 	 * Otherwise, if we have knowledge of the local port and address,
421 	 * deliver only to that socket.
422 	 */
423 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
424 		fport = 0;
425 		lport = 0;
426 		laddr.s_addr = 0;
427 		if (cmd != PRC_HOSTDEAD)
428 			notify = in_rtchange;
429 	}
430 	errno = inetctlerrmap[cmd];
431 	s = splnet();
432 	for (inp = head->lh_first; inp != NULL;) {
433 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
434 		    inp->inp_socket == 0 ||
435 		    (lport && inp->inp_lport != lport) ||
436 		    (laddr.s_addr && inp->inp_laddr.s_addr != laddr.s_addr) ||
437 		    (fport && inp->inp_fport != fport)) {
438 			inp = inp->inp_list.le_next;
439 			continue;
440 		}
441 		oinp = inp;
442 		inp = inp->inp_list.le_next;
443 		if (notify)
444 			(*notify)(oinp, errno);
445 	}
446 	splx(s);
447 }
448 
449 /*
450  * Check for alternatives when higher level complains
451  * about service problems.  For now, invalidate cached
452  * routing information.  If the route was created dynamically
453  * (by a redirect), time to try a default gateway again.
454  */
455 void
456 in_losing(inp)
457 	struct inpcb *inp;
458 {
459 	register struct rtentry *rt;
460 	struct rt_addrinfo info;
461 
462 	if ((rt = inp->inp_route.ro_rt)) {
463 		inp->inp_route.ro_rt = 0;
464 		bzero((caddr_t)&info, sizeof(info));
465 		info.rti_info[RTAX_DST] =
466 			(struct sockaddr *)&inp->inp_route.ro_dst;
467 		info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
468 		info.rti_info[RTAX_NETMASK] = rt_mask(rt);
469 		rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
470 		if (rt->rt_flags & RTF_DYNAMIC)
471 			(void) rtrequest(RTM_DELETE, rt_key(rt),
472 				rt->rt_gateway, rt_mask(rt), rt->rt_flags,
473 				(struct rtentry **)0);
474 		else
475 		/*
476 		 * A new route can be allocated
477 		 * the next time output is attempted.
478 		 */
479 			rtfree(rt);
480 	}
481 }
482 
483 /*
484  * After a routing change, flush old routing
485  * and allocate a (hopefully) better one.
486  */
487 void
488 in_rtchange(inp, errno)
489 	register struct inpcb *inp;
490 	int errno;
491 {
492 	if (inp->inp_route.ro_rt) {
493 		rtfree(inp->inp_route.ro_rt);
494 		inp->inp_route.ro_rt = 0;
495 		/*
496 		 * A new route can be allocated the next time
497 		 * output is attempted.
498 		 */
499 	}
500 }
501 
502 struct inpcb *
503 in_pcblookup(head, faddr, fport_arg, laddr, lport_arg, flags)
504 	struct inpcbhead *head;
505 	struct in_addr faddr, laddr;
506 	u_int fport_arg, lport_arg;
507 	int flags;
508 {
509 	register struct inpcb *inp, *match = NULL;
510 	int matchwild = 3, wildcard;
511 	u_short fport = fport_arg, lport = lport_arg;
512 	int s;
513 
514 	s = splnet();
515 
516 	for (inp = head->lh_first; inp != NULL; inp = inp->inp_list.le_next) {
517 		if (inp->inp_lport != lport)
518 			continue;
519 		wildcard = 0;
520 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
521 			if (faddr.s_addr == INADDR_ANY)
522 				wildcard++;
523 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
524 			    inp->inp_fport != fport)
525 				continue;
526 		} else {
527 			if (faddr.s_addr != INADDR_ANY)
528 				wildcard++;
529 		}
530 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
531 			if (laddr.s_addr == INADDR_ANY)
532 				wildcard++;
533 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
534 				continue;
535 		} else {
536 			if (laddr.s_addr != INADDR_ANY)
537 				wildcard++;
538 		}
539 		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
540 			continue;
541 		if (wildcard < matchwild) {
542 			match = inp;
543 			matchwild = wildcard;
544 			if (matchwild == 0) {
545 				break;
546 			}
547 		}
548 	}
549 	splx(s);
550 	return (match);
551 }
552 
553 /*
554  * Lookup PCB in hash list.
555  */
556 struct inpcb *
557 in_pcblookuphash(pcbinfo, faddr, fport_arg, laddr, lport_arg)
558 	struct inpcbinfo *pcbinfo;
559 	struct in_addr faddr, laddr;
560 	u_int fport_arg, lport_arg;
561 {
562 	struct inpcbhead *head;
563 	register struct inpcb *inp;
564 	u_short fport = fport_arg, lport = lport_arg;
565 	int s;
566 
567 	s = splnet();
568 	/*
569 	 * First look for an exact match.
570 	 */
571 	head = &pcbinfo->hashbase[(faddr.s_addr + lport + fport) % pcbinfo->hashsize];
572 
573 	for (inp = head->lh_first; inp != NULL; inp = inp->inp_hash.le_next) {
574 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
575 		    inp->inp_fport != fport ||
576 		    inp->inp_lport != lport ||
577 		    inp->inp_laddr.s_addr != laddr.s_addr)
578 			continue;
579 		/*
580 		 * Move PCB to head of this hash chain so that it can be
581 		 * found more quickly in the future.
582 		 */
583 		if (inp != head->lh_first) {
584 			LIST_REMOVE(inp, inp_hash);
585 			LIST_INSERT_HEAD(head, inp, inp_hash);
586 		}
587 		break;
588 	}
589 	splx(s);
590 	return (inp);
591 }
592 
593 /*
594  * Insert PCB into hash chain. Must be called at splnet.
595  */
596 void
597 in_pcbinshash(inp)
598 	struct inpcb *inp;
599 {
600 	struct inpcbhead *head;
601 
602 	head = &inp->inp_pcbinfo->hashbase[(inp->inp_faddr.s_addr +
603 		inp->inp_lport + inp->inp_fport) % inp->inp_pcbinfo->hashsize];
604 
605 	LIST_INSERT_HEAD(head, inp, inp_hash);
606 }
607 
608 void
609 in_pcbrehash(inp)
610 	struct inpcb *inp;
611 {
612 	struct inpcbhead *head;
613 	int s;
614 
615 	s = splnet();
616 	LIST_REMOVE(inp, inp_hash);
617 
618 	head = &inp->inp_pcbinfo->hashbase[(inp->inp_faddr.s_addr +
619 		inp->inp_lport + inp->inp_fport) % inp->inp_pcbinfo->hashsize];
620 
621 	LIST_INSERT_HEAD(head, inp, inp_hash);
622 	splx(s);
623 }
624