xref: /freebsd/sys/netinet/in_pcb.c (revision e627b39baccd1ec9129690167cf5e6d860509655)
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 1.20 1996/08/12 14:05:54 peter Exp $
35  */
36 
37 #include <sys/param.h>
38 #include <sys/queue.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/protosw.h>
43 #include <sys/socket.h>
44 #include <sys/socketvar.h>
45 #include <sys/ioctl.h>
46 #include <sys/errno.h>
47 #include <sys/time.h>
48 #include <sys/proc.h>
49 #include <sys/kernel.h>
50 #include <sys/sysctl.h>
51 
52 #include <net/if.h>
53 #include <net/route.h>
54 
55 #include <netinet/in.h>
56 #include <netinet/in_systm.h>
57 #include <netinet/ip.h>
58 #include <netinet/in_pcb.h>
59 #include <netinet/in_var.h>
60 #include <netinet/ip_var.h>
61 
62 struct	in_addr zeroin_addr;
63 
64 static void	 in_pcbinshash __P((struct inpcb *));
65 static void	 in_rtchange __P((struct inpcb *, int));
66 
67 /*
68  * These configure the range of local port addresses assigned to
69  * "unspecified" outgoing connections/packets/whatever.
70  */
71 static int ipport_lowfirstauto  = IPPORT_RESERVED - 1;	/* 1023 */
72 static int ipport_lowlastauto = IPPORT_RESERVEDSTART;	/* 600 */
73 static int ipport_firstauto = IPPORT_RESERVED;		/* 1024 */
74 static int ipport_lastauto  = IPPORT_USERRESERVED;	/* 5000 */
75 static int ipport_hifirstauto = IPPORT_HIFIRSTAUTO;	/* 40000 */
76 static int ipport_hilastauto  = IPPORT_HILASTAUTO;	/* 44999 */
77 
78 #define RANGECHK(var, min, max) \
79 	if ((var) < (min)) { (var) = (min); } \
80 	else if ((var) > (max)) { (var) = (max); }
81 
82 static int
83 sysctl_net_ipport_check SYSCTL_HANDLER_ARGS
84 {
85 	int error = sysctl_handle_int(oidp,
86 		oidp->oid_arg1, oidp->oid_arg2, req);
87 	if (!error) {
88 		RANGECHK(ipport_lowfirstauto, 1, IPPORT_RESERVED - 1);
89 		RANGECHK(ipport_lowlastauto, 1, IPPORT_RESERVED - 1);
90 		RANGECHK(ipport_firstauto, IPPORT_RESERVED, USHRT_MAX);
91 		RANGECHK(ipport_lastauto, IPPORT_RESERVED, USHRT_MAX);
92 		RANGECHK(ipport_hifirstauto, IPPORT_RESERVED, USHRT_MAX);
93 		RANGECHK(ipport_hilastauto, IPPORT_RESERVED, USHRT_MAX);
94 	}
95 	return error;
96 }
97 
98 #undef RANGECHK
99 
100 SYSCTL_NODE(_net_inet_ip, IPPROTO_IP, portrange, CTLFLAG_RW, 0, "IP Ports");
101 
102 SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, lowfirst, CTLTYPE_INT|CTLFLAG_RW,
103 	   &ipport_lowfirstauto, 0, &sysctl_net_ipport_check, "I", "");
104 SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, lowlast, CTLTYPE_INT|CTLFLAG_RW,
105 	   &ipport_lowlastauto, 0, &sysctl_net_ipport_check, "I", "");
106 SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, first, CTLTYPE_INT|CTLFLAG_RW,
107 	   &ipport_firstauto, 0, &sysctl_net_ipport_check, "I", "");
108 SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, last, CTLTYPE_INT|CTLFLAG_RW,
109 	   &ipport_lastauto, 0, &sysctl_net_ipport_check, "I", "");
110 SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, hifirst, CTLTYPE_INT|CTLFLAG_RW,
111 	   &ipport_hifirstauto, 0, &sysctl_net_ipport_check, "I", "");
112 SYSCTL_PROC(_net_inet_ip_portrange, OID_AUTO, hilast, CTLTYPE_INT|CTLFLAG_RW,
113 	   &ipport_hilastauto, 0, &sysctl_net_ipport_check, "I", "");
114 
115 int
116 in_pcballoc(so, pcbinfo)
117 	struct socket *so;
118 	struct inpcbinfo *pcbinfo;
119 {
120 	register struct inpcb *inp;
121 	int s;
122 
123 	MALLOC(inp, struct inpcb *, sizeof(*inp), M_PCB, M_NOWAIT);
124 	if (inp == NULL)
125 		return (ENOBUFS);
126 	bzero((caddr_t)inp, sizeof(*inp));
127 	inp->inp_pcbinfo = pcbinfo;
128 	inp->inp_socket = so;
129 	s = splnet();
130 	LIST_INSERT_HEAD(pcbinfo->listhead, inp, inp_list);
131 	in_pcbinshash(inp);
132 	splx(s);
133 	so->so_pcb = (caddr_t)inp;
134 	return (0);
135 }
136 
137 int
138 in_pcbbind(inp, nam)
139 	register struct inpcb *inp;
140 	struct mbuf *nam;
141 {
142 	register struct socket *so = inp->inp_socket;
143 	struct inpcbhead *head = inp->inp_pcbinfo->listhead;
144 	unsigned short *lastport = &inp->inp_pcbinfo->lastport;
145 	struct sockaddr_in *sin;
146 	struct proc *p = curproc;		/* XXX */
147 	u_short lport = 0;
148 	int wild = 0, reuseport = (so->so_options & SO_REUSEPORT);
149 	int error;
150 
151 	if (in_ifaddr == 0)
152 		return (EADDRNOTAVAIL);
153 	if (inp->inp_lport || inp->inp_laddr.s_addr != INADDR_ANY)
154 		return (EINVAL);
155 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0 &&
156 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
157 	     (so->so_options & SO_ACCEPTCONN) == 0))
158 		wild = INPLOOKUP_WILDCARD;
159 	if (nam) {
160 		sin = mtod(nam, struct sockaddr_in *);
161 		if (nam->m_len != sizeof (*sin))
162 			return (EINVAL);
163 #ifdef notdef
164 		/*
165 		 * We should check the family, but old programs
166 		 * incorrectly fail to initialize it.
167 		 */
168 		if (sin->sin_family != AF_INET)
169 			return (EAFNOSUPPORT);
170 #endif
171 		lport = sin->sin_port;
172 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) {
173 			/*
174 			 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
175 			 * allow complete duplication of binding if
176 			 * SO_REUSEPORT is set, or if SO_REUSEADDR is set
177 			 * and a multicast address is bound on both
178 			 * new and duplicated sockets.
179 			 */
180 			if (so->so_options & SO_REUSEADDR)
181 				reuseport = SO_REUSEADDR|SO_REUSEPORT;
182 		} else if (sin->sin_addr.s_addr != INADDR_ANY) {
183 			sin->sin_port = 0;		/* yech... */
184 			if (ifa_ifwithaddr((struct sockaddr *)sin) == 0)
185 				return (EADDRNOTAVAIL);
186 		}
187 		if (lport) {
188 			struct inpcb *t;
189 
190 			/* GROSS */
191 			if (ntohs(lport) < IPPORT_RESERVED &&
192 			    (error = suser(p->p_ucred, &p->p_acflag)))
193 				return (EACCES);
194 			t = in_pcblookup(head, zeroin_addr, 0,
195 			    sin->sin_addr, lport, wild);
196 			if (t && (reuseport & t->inp_socket->so_options) == 0)
197 				return (EADDRINUSE);
198 		}
199 		inp->inp_laddr = sin->sin_addr;
200 	}
201 	if (lport == 0) {
202 		ushort first, last;
203 		int count;
204 
205 		inp->inp_flags |= INP_ANONPORT;
206 
207 		if (inp->inp_flags & INP_HIGHPORT) {
208 			first = ipport_hifirstauto;	/* sysctl */
209 			last  = ipport_hilastauto;
210 		} else if (inp->inp_flags & INP_LOWPORT) {
211 			if (error = suser(p->p_ucred, &p->p_acflag))
212 				return (EACCES);
213 			first = ipport_lowfirstauto;	/* 1023 */
214 			last  = ipport_lowlastauto;	/* 600 */
215 		} else {
216 			first = ipport_firstauto;	/* sysctl */
217 			last  = ipport_lastauto;
218 		}
219 		/*
220 		 * Simple check to ensure all ports are not used up causing
221 		 * a deadlock here.
222 		 *
223 		 * We split the two cases (up and down) so that the direction
224 		 * is not being tested on each round of the loop.
225 		 */
226 		if (first > last) {
227 			/*
228 			 * counting down
229 			 */
230 			count = first - last;
231 
232 			do {
233 				if (count-- <= 0)	/* completely used? */
234 					return (EADDRNOTAVAIL);
235 				--*lastport;
236 				if (*lastport > first || *lastport < last)
237 					*lastport = first;
238 				lport = htons(*lastport);
239 			} while (in_pcblookup(head,
240 				 zeroin_addr, 0, inp->inp_laddr, lport, wild));
241 		} else {
242 			/*
243 			 * counting up
244 			 */
245 			count = last - first;
246 
247 			do {
248 				if (count-- <= 0)	/* completely used? */
249 					return (EADDRNOTAVAIL);
250 				++*lastport;
251 				if (*lastport < first || *lastport > last)
252 					*lastport = first;
253 				lport = htons(*lastport);
254 			} while (in_pcblookup(head,
255 				 zeroin_addr, 0, inp->inp_laddr, lport, wild));
256 		}
257 	}
258 	inp->inp_lport = lport;
259 	in_pcbrehash(inp);
260 	return (0);
261 }
262 
263 /*
264  *   Transform old in_pcbconnect() into an inner subroutine for new
265  *   in_pcbconnect(): Do some validity-checking on the remote
266  *   address (in mbuf 'nam') and then determine local host address
267  *   (i.e., which interface) to use to access that remote host.
268  *
269  *   This preserves definition of in_pcbconnect(), while supporting a
270  *   slightly different version for T/TCP.  (This is more than
271  *   a bit of a kludge, but cleaning up the internal interfaces would
272  *   have forced minor changes in every protocol).
273  */
274 
275 int
276 in_pcbladdr(inp, nam, plocal_sin)
277 	register struct inpcb *inp;
278 	struct mbuf *nam;
279 	struct sockaddr_in **plocal_sin;
280 {
281 	struct in_ifaddr *ia;
282 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
283 
284 	if (nam->m_len != sizeof (*sin))
285 		return (EINVAL);
286 	if (sin->sin_family != AF_INET)
287 		return (EAFNOSUPPORT);
288 	if (sin->sin_port == 0)
289 		return (EADDRNOTAVAIL);
290 	if (in_ifaddr) {
291 		/*
292 		 * If the destination address is INADDR_ANY,
293 		 * use the primary local address.
294 		 * If the supplied address is INADDR_BROADCAST,
295 		 * and the primary interface supports broadcast,
296 		 * choose the broadcast address for that interface.
297 		 */
298 #define	satosin(sa)	((struct sockaddr_in *)(sa))
299 #define sintosa(sin)	((struct sockaddr *)(sin))
300 #define ifatoia(ifa)	((struct in_ifaddr *)(ifa))
301 		if (sin->sin_addr.s_addr == INADDR_ANY)
302 		    sin->sin_addr = IA_SIN(in_ifaddr)->sin_addr;
303 		else if (sin->sin_addr.s_addr == (u_long)INADDR_BROADCAST &&
304 		  (in_ifaddr->ia_ifp->if_flags & IFF_BROADCAST))
305 		    sin->sin_addr = satosin(&in_ifaddr->ia_broadaddr)->sin_addr;
306 	}
307 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
308 		register struct route *ro;
309 
310 		ia = (struct in_ifaddr *)0;
311 		/*
312 		 * If route is known or can be allocated now,
313 		 * our src addr is taken from the i/f, else punt.
314 		 */
315 		ro = &inp->inp_route;
316 		if (ro->ro_rt &&
317 		    (satosin(&ro->ro_dst)->sin_addr.s_addr !=
318 			sin->sin_addr.s_addr ||
319 		    inp->inp_socket->so_options & SO_DONTROUTE)) {
320 			RTFREE(ro->ro_rt);
321 			ro->ro_rt = (struct rtentry *)0;
322 		}
323 		if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0 && /*XXX*/
324 		    (ro->ro_rt == (struct rtentry *)0 ||
325 		    ro->ro_rt->rt_ifp == (struct ifnet *)0)) {
326 			/* No route yet, so try to acquire one */
327 			ro->ro_dst.sa_family = AF_INET;
328 			ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
329 			((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
330 				sin->sin_addr;
331 			rtalloc(ro);
332 		}
333 		/*
334 		 * If we found a route, use the address
335 		 * corresponding to the outgoing interface
336 		 * unless it is the loopback (in case a route
337 		 * to our address on another net goes to loopback).
338 		 */
339 		if (ro->ro_rt && !(ro->ro_rt->rt_ifp->if_flags & IFF_LOOPBACK))
340 			ia = ifatoia(ro->ro_rt->rt_ifa);
341 		if (ia == 0) {
342 			u_short fport = sin->sin_port;
343 
344 			sin->sin_port = 0;
345 			ia = ifatoia(ifa_ifwithdstaddr(sintosa(sin)));
346 			if (ia == 0)
347 				ia = ifatoia(ifa_ifwithnet(sintosa(sin)));
348 			sin->sin_port = fport;
349 			if (ia == 0)
350 				ia = in_ifaddr;
351 			if (ia == 0)
352 				return (EADDRNOTAVAIL);
353 		}
354 		/*
355 		 * If the destination address is multicast and an outgoing
356 		 * interface has been set as a multicast option, use the
357 		 * address of that interface as our source address.
358 		 */
359 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr)) &&
360 		    inp->inp_moptions != NULL) {
361 			struct ip_moptions *imo;
362 			struct ifnet *ifp;
363 
364 			imo = inp->inp_moptions;
365 			if (imo->imo_multicast_ifp != NULL) {
366 				ifp = imo->imo_multicast_ifp;
367 				for (ia = in_ifaddr; ia; ia = ia->ia_next)
368 					if (ia->ia_ifp == ifp)
369 						break;
370 				if (ia == 0)
371 					return (EADDRNOTAVAIL);
372 			}
373 		}
374 	/*
375 	 * Don't do pcblookup call here; return interface in plocal_sin
376 	 * and exit to caller, that will do the lookup.
377 	 */
378 		*plocal_sin = &ia->ia_addr;
379 
380 	}
381 	return(0);
382 }
383 
384 /*
385  * Outer subroutine:
386  * Connect from a socket to a specified address.
387  * Both address and port must be specified in argument sin.
388  * If don't have a local address for this socket yet,
389  * then pick one.
390  */
391 int
392 in_pcbconnect(inp, nam)
393 	register struct inpcb *inp;
394 	struct mbuf *nam;
395 {
396 	struct sockaddr_in *ifaddr;
397 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
398 	int error;
399 
400 	/*
401 	 *   Call inner routine, to assign local interface address.
402 	 */
403 	if (error = in_pcbladdr(inp, nam, &ifaddr))
404 		return(error);
405 
406 	if (in_pcblookuphash(inp->inp_pcbinfo, sin->sin_addr, sin->sin_port,
407 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
408 	    inp->inp_lport) != NULL)
409 		return (EADDRINUSE);
410 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
411 		if (inp->inp_lport == 0)
412 			(void)in_pcbbind(inp, (struct mbuf *)0);
413 		inp->inp_laddr = ifaddr->sin_addr;
414 	}
415 	inp->inp_faddr = sin->sin_addr;
416 	inp->inp_fport = sin->sin_port;
417 	in_pcbrehash(inp);
418 	return (0);
419 }
420 
421 void
422 in_pcbdisconnect(inp)
423 	struct inpcb *inp;
424 {
425 
426 	inp->inp_faddr.s_addr = INADDR_ANY;
427 	inp->inp_fport = 0;
428 	in_pcbrehash(inp);
429 	if (inp->inp_socket->so_state & SS_NOFDREF)
430 		in_pcbdetach(inp);
431 }
432 
433 void
434 in_pcbdetach(inp)
435 	struct inpcb *inp;
436 {
437 	struct socket *so = inp->inp_socket;
438 	int s;
439 
440 	so->so_pcb = 0;
441 	sofree(so);
442 	if (inp->inp_options)
443 		(void)m_free(inp->inp_options);
444 	if (inp->inp_route.ro_rt)
445 		rtfree(inp->inp_route.ro_rt);
446 	ip_freemoptions(inp->inp_moptions);
447 	s = splnet();
448 	LIST_REMOVE(inp, inp_hash);
449 	LIST_REMOVE(inp, inp_list);
450 	splx(s);
451 	FREE(inp, M_PCB);
452 }
453 
454 void
455 in_setsockaddr(inp, nam)
456 	register struct inpcb *inp;
457 	struct mbuf *nam;
458 {
459 	register struct sockaddr_in *sin;
460 
461 	nam->m_len = sizeof (*sin);
462 	sin = mtod(nam, struct sockaddr_in *);
463 	bzero((caddr_t)sin, sizeof (*sin));
464 	sin->sin_family = AF_INET;
465 	sin->sin_len = sizeof(*sin);
466 	sin->sin_port = inp->inp_lport;
467 	sin->sin_addr = inp->inp_laddr;
468 }
469 
470 void
471 in_setpeeraddr(inp, nam)
472 	struct inpcb *inp;
473 	struct mbuf *nam;
474 {
475 	register struct sockaddr_in *sin;
476 
477 	nam->m_len = sizeof (*sin);
478 	sin = mtod(nam, struct sockaddr_in *);
479 	bzero((caddr_t)sin, sizeof (*sin));
480 	sin->sin_family = AF_INET;
481 	sin->sin_len = sizeof(*sin);
482 	sin->sin_port = inp->inp_fport;
483 	sin->sin_addr = inp->inp_faddr;
484 }
485 
486 /*
487  * Pass some notification to all connections of a protocol
488  * associated with address dst.  The local address and/or port numbers
489  * may be specified to limit the search.  The "usual action" will be
490  * taken, depending on the ctlinput cmd.  The caller must filter any
491  * cmds that are uninteresting (e.g., no error in the map).
492  * Call the protocol specific routine (if any) to report
493  * any errors for each matching socket.
494  *
495  * Must be called at splnet.
496  */
497 void
498 in_pcbnotify(head, dst, fport_arg, laddr, lport_arg, cmd, notify)
499 	struct inpcbhead *head;
500 	struct sockaddr *dst;
501 	u_int fport_arg, lport_arg;
502 	struct in_addr laddr;
503 	int cmd;
504 	void (*notify) __P((struct inpcb *, int));
505 {
506 	register struct inpcb *inp, *oinp;
507 	struct in_addr faddr;
508 	u_short fport = fport_arg, lport = lport_arg;
509 	int errno, s;
510 
511 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET)
512 		return;
513 	faddr = ((struct sockaddr_in *)dst)->sin_addr;
514 	if (faddr.s_addr == INADDR_ANY)
515 		return;
516 
517 	/*
518 	 * Redirects go to all references to the destination,
519 	 * and use in_rtchange to invalidate the route cache.
520 	 * Dead host indications: notify all references to the destination.
521 	 * Otherwise, if we have knowledge of the local port and address,
522 	 * deliver only to that socket.
523 	 */
524 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
525 		fport = 0;
526 		lport = 0;
527 		laddr.s_addr = 0;
528 		if (cmd != PRC_HOSTDEAD)
529 			notify = in_rtchange;
530 	}
531 	errno = inetctlerrmap[cmd];
532 	s = splnet();
533 	for (inp = head->lh_first; inp != NULL;) {
534 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
535 		    inp->inp_socket == 0 ||
536 		    (lport && inp->inp_lport != lport) ||
537 		    (laddr.s_addr && inp->inp_laddr.s_addr != laddr.s_addr) ||
538 		    (fport && inp->inp_fport != fport)) {
539 			inp = inp->inp_list.le_next;
540 			continue;
541 		}
542 		oinp = inp;
543 		inp = inp->inp_list.le_next;
544 		if (notify)
545 			(*notify)(oinp, errno);
546 	}
547 	splx(s);
548 }
549 
550 /*
551  * Check for alternatives when higher level complains
552  * about service problems.  For now, invalidate cached
553  * routing information.  If the route was created dynamically
554  * (by a redirect), time to try a default gateway again.
555  */
556 void
557 in_losing(inp)
558 	struct inpcb *inp;
559 {
560 	register struct rtentry *rt;
561 	struct rt_addrinfo info;
562 
563 	if ((rt = inp->inp_route.ro_rt)) {
564 		inp->inp_route.ro_rt = 0;
565 		bzero((caddr_t)&info, sizeof(info));
566 		info.rti_info[RTAX_DST] =
567 			(struct sockaddr *)&inp->inp_route.ro_dst;
568 		info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
569 		info.rti_info[RTAX_NETMASK] = rt_mask(rt);
570 		rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
571 		if (rt->rt_flags & RTF_DYNAMIC)
572 			(void) rtrequest(RTM_DELETE, rt_key(rt),
573 				rt->rt_gateway, rt_mask(rt), rt->rt_flags,
574 				(struct rtentry **)0);
575 		else
576 		/*
577 		 * A new route can be allocated
578 		 * the next time output is attempted.
579 		 */
580 			rtfree(rt);
581 	}
582 }
583 
584 /*
585  * After a routing change, flush old routing
586  * and allocate a (hopefully) better one.
587  */
588 static void
589 in_rtchange(inp, errno)
590 	register struct inpcb *inp;
591 	int errno;
592 {
593 	if (inp->inp_route.ro_rt) {
594 		rtfree(inp->inp_route.ro_rt);
595 		inp->inp_route.ro_rt = 0;
596 		/*
597 		 * A new route can be allocated the next time
598 		 * output is attempted.
599 		 */
600 	}
601 }
602 
603 struct inpcb *
604 in_pcblookup(head, faddr, fport_arg, laddr, lport_arg, flags)
605 	struct inpcbhead *head;
606 	struct in_addr faddr, laddr;
607 	u_int fport_arg, lport_arg;
608 	int flags;
609 {
610 	register struct inpcb *inp, *match = NULL;
611 	int matchwild = 3, wildcard;
612 	u_short fport = fport_arg, lport = lport_arg;
613 	int s;
614 
615 	s = splnet();
616 
617 	for (inp = head->lh_first; inp != NULL; inp = inp->inp_list.le_next) {
618 		if (inp->inp_lport != lport)
619 			continue;
620 		wildcard = 0;
621 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
622 			if (faddr.s_addr == INADDR_ANY)
623 				wildcard++;
624 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
625 			    inp->inp_fport != fport)
626 				continue;
627 		} else {
628 			if (faddr.s_addr != INADDR_ANY)
629 				wildcard++;
630 		}
631 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
632 			if (laddr.s_addr == INADDR_ANY)
633 				wildcard++;
634 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
635 				continue;
636 		} else {
637 			if (laddr.s_addr != INADDR_ANY)
638 				wildcard++;
639 		}
640 		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
641 			continue;
642 		if (wildcard < matchwild) {
643 			match = inp;
644 			matchwild = wildcard;
645 			if (matchwild == 0) {
646 				break;
647 			}
648 		}
649 	}
650 	splx(s);
651 	return (match);
652 }
653 
654 /*
655  * Lookup PCB in hash list.
656  */
657 struct inpcb *
658 in_pcblookuphash(pcbinfo, faddr, fport_arg, laddr, lport_arg)
659 	struct inpcbinfo *pcbinfo;
660 	struct in_addr faddr, laddr;
661 	u_int fport_arg, lport_arg;
662 {
663 	struct inpcbhead *head;
664 	register struct inpcb *inp;
665 	u_short fport = fport_arg, lport = lport_arg;
666 	int s;
667 
668 	s = splnet();
669 	/*
670 	 * First look for an exact match.
671 	 */
672 	head = &pcbinfo->hashbase[(faddr.s_addr + lport + fport) % pcbinfo->hashsize];
673 
674 	for (inp = head->lh_first; inp != NULL; inp = inp->inp_hash.le_next) {
675 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
676 		    inp->inp_fport != fport ||
677 		    inp->inp_lport != lport ||
678 		    inp->inp_laddr.s_addr != laddr.s_addr)
679 			continue;
680 		/*
681 		 * Move PCB to head of this hash chain so that it can be
682 		 * found more quickly in the future.
683 		 */
684 		if (inp != head->lh_first) {
685 			LIST_REMOVE(inp, inp_hash);
686 			LIST_INSERT_HEAD(head, inp, inp_hash);
687 		}
688 		break;
689 	}
690 	splx(s);
691 	return (inp);
692 }
693 
694 /*
695  * Insert PCB into hash chain. Must be called at splnet.
696  */
697 static void
698 in_pcbinshash(inp)
699 	struct inpcb *inp;
700 {
701 	struct inpcbhead *head;
702 
703 	head = &inp->inp_pcbinfo->hashbase[(inp->inp_faddr.s_addr +
704 		inp->inp_lport + inp->inp_fport) % inp->inp_pcbinfo->hashsize];
705 
706 	LIST_INSERT_HEAD(head, inp, inp_hash);
707 }
708 
709 void
710 in_pcbrehash(inp)
711 	struct inpcb *inp;
712 {
713 	struct inpcbhead *head;
714 	int s;
715 
716 	s = splnet();
717 	LIST_REMOVE(inp, inp_hash);
718 
719 	head = &inp->inp_pcbinfo->hashbase[(inp->inp_faddr.s_addr +
720 		inp->inp_lport + inp->inp_fport) % inp->inp_pcbinfo->hashsize];
721 
722 	LIST_INSERT_HEAD(head, inp, inp_hash);
723 	splx(s);
724 }
725