xref: /freebsd/sys/netinet/in_pcb.c (revision bcd92649c9952c9c9e8845dbd34276a60dd16664)
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 1.22 1996/10/07 19:06:07 davidg 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 	unsigned short *lastport;
144 	struct sockaddr_in *sin;
145 	struct proc *p = curproc;		/* XXX */
146 	u_short lport = 0;
147 	int wild = 0, reuseport = (so->so_options & SO_REUSEPORT);
148 	int error;
149 
150 	if (in_ifaddr == 0)
151 		return (EADDRNOTAVAIL);
152 	if (inp->inp_lport || inp->inp_laddr.s_addr != INADDR_ANY)
153 		return (EINVAL);
154 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0 &&
155 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
156 	     (so->so_options & SO_ACCEPTCONN) == 0))
157 		wild = 1;
158 	if (nam) {
159 		sin = mtod(nam, struct sockaddr_in *);
160 		if (nam->m_len != sizeof (*sin))
161 			return (EINVAL);
162 #ifdef notdef
163 		/*
164 		 * We should check the family, but old programs
165 		 * incorrectly fail to initialize it.
166 		 */
167 		if (sin->sin_family != AF_INET)
168 			return (EAFNOSUPPORT);
169 #endif
170 		lport = sin->sin_port;
171 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) {
172 			/*
173 			 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
174 			 * allow complete duplication of binding if
175 			 * SO_REUSEPORT is set, or if SO_REUSEADDR is set
176 			 * and a multicast address is bound on both
177 			 * new and duplicated sockets.
178 			 */
179 			if (so->so_options & SO_REUSEADDR)
180 				reuseport = SO_REUSEADDR|SO_REUSEPORT;
181 		} else if (sin->sin_addr.s_addr != INADDR_ANY) {
182 			sin->sin_port = 0;		/* yech... */
183 			if (ifa_ifwithaddr((struct sockaddr *)sin) == 0)
184 				return (EADDRNOTAVAIL);
185 		}
186 		if (lport) {
187 			struct inpcb *t;
188 
189 			/* GROSS */
190 			if (ntohs(lport) < IPPORT_RESERVED &&
191 			    (error = suser(p->p_ucred, &p->p_acflag)))
192 				return (EACCES);
193 			t = in_pcblookup(inp->inp_pcbinfo, zeroin_addr, 0,
194 			    sin->sin_addr, lport, wild);
195 			if (t && (reuseport & t->inp_socket->so_options) == 0)
196 				return (EADDRINUSE);
197 		}
198 		inp->inp_laddr = sin->sin_addr;
199 	}
200 	if (lport == 0) {
201 		ushort first, last;
202 		int count;
203 
204 		inp->inp_flags |= INP_ANONPORT;
205 
206 		if (inp->inp_flags & INP_HIGHPORT) {
207 			first = ipport_hifirstauto;	/* sysctl */
208 			last  = ipport_hilastauto;
209 			lastport = &inp->inp_pcbinfo->lasthi;
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 			lastport = &inp->inp_pcbinfo->lastlow;
216 		} else {
217 			first = ipport_firstauto;	/* sysctl */
218 			last  = ipport_lastauto;
219 			lastport = &inp->inp_pcbinfo->lastport;
220 		}
221 		/*
222 		 * Simple check to ensure all ports are not used up causing
223 		 * a deadlock here.
224 		 *
225 		 * We split the two cases (up and down) so that the direction
226 		 * is not being tested on each round of the loop.
227 		 */
228 		if (first > last) {
229 			/*
230 			 * counting down
231 			 */
232 			count = first - last;
233 
234 			do {
235 				if (count-- <= 0)	/* completely used? */
236 					return (EADDRNOTAVAIL);
237 				--*lastport;
238 				if (*lastport > first || *lastport < last)
239 					*lastport = first;
240 				lport = htons(*lastport);
241 			} while (in_pcblookup(inp->inp_pcbinfo,
242 				 zeroin_addr, 0, inp->inp_laddr, lport, wild));
243 		} else {
244 			/*
245 			 * counting up
246 			 */
247 			count = last - first;
248 
249 			do {
250 				if (count-- <= 0)	/* completely used? */
251 					return (EADDRNOTAVAIL);
252 				++*lastport;
253 				if (*lastport < first || *lastport > last)
254 					*lastport = first;
255 				lport = htons(*lastport);
256 			} while (in_pcblookup(inp->inp_pcbinfo,
257 				 zeroin_addr, 0, inp->inp_laddr, lport, wild));
258 		}
259 	}
260 	inp->inp_lport = lport;
261 	in_pcbrehash(inp);
262 	return (0);
263 }
264 
265 /*
266  *   Transform old in_pcbconnect() into an inner subroutine for new
267  *   in_pcbconnect(): Do some validity-checking on the remote
268  *   address (in mbuf 'nam') and then determine local host address
269  *   (i.e., which interface) to use to access that remote host.
270  *
271  *   This preserves definition of in_pcbconnect(), while supporting a
272  *   slightly different version for T/TCP.  (This is more than
273  *   a bit of a kludge, but cleaning up the internal interfaces would
274  *   have forced minor changes in every protocol).
275  */
276 
277 int
278 in_pcbladdr(inp, nam, plocal_sin)
279 	register struct inpcb *inp;
280 	struct mbuf *nam;
281 	struct sockaddr_in **plocal_sin;
282 {
283 	struct in_ifaddr *ia;
284 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
285 
286 	if (nam->m_len != sizeof (*sin))
287 		return (EINVAL);
288 	if (sin->sin_family != AF_INET)
289 		return (EAFNOSUPPORT);
290 	if (sin->sin_port == 0)
291 		return (EADDRNOTAVAIL);
292 	if (in_ifaddr) {
293 		/*
294 		 * If the destination address is INADDR_ANY,
295 		 * use the primary local address.
296 		 * If the supplied address is INADDR_BROADCAST,
297 		 * and the primary interface supports broadcast,
298 		 * choose the broadcast address for that interface.
299 		 */
300 #define	satosin(sa)	((struct sockaddr_in *)(sa))
301 #define sintosa(sin)	((struct sockaddr *)(sin))
302 #define ifatoia(ifa)	((struct in_ifaddr *)(ifa))
303 		if (sin->sin_addr.s_addr == INADDR_ANY)
304 		    sin->sin_addr = IA_SIN(in_ifaddr)->sin_addr;
305 		else if (sin->sin_addr.s_addr == (u_long)INADDR_BROADCAST &&
306 		  (in_ifaddr->ia_ifp->if_flags & IFF_BROADCAST))
307 		    sin->sin_addr = satosin(&in_ifaddr->ia_broadaddr)->sin_addr;
308 	}
309 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
310 		register struct route *ro;
311 
312 		ia = (struct in_ifaddr *)0;
313 		/*
314 		 * If route is known or can be allocated now,
315 		 * our src addr is taken from the i/f, else punt.
316 		 */
317 		ro = &inp->inp_route;
318 		if (ro->ro_rt &&
319 		    (satosin(&ro->ro_dst)->sin_addr.s_addr !=
320 			sin->sin_addr.s_addr ||
321 		    inp->inp_socket->so_options & SO_DONTROUTE)) {
322 			RTFREE(ro->ro_rt);
323 			ro->ro_rt = (struct rtentry *)0;
324 		}
325 		if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0 && /*XXX*/
326 		    (ro->ro_rt == (struct rtentry *)0 ||
327 		    ro->ro_rt->rt_ifp == (struct ifnet *)0)) {
328 			/* No route yet, so try to acquire one */
329 			ro->ro_dst.sa_family = AF_INET;
330 			ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
331 			((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
332 				sin->sin_addr;
333 			rtalloc(ro);
334 		}
335 		/*
336 		 * If we found a route, use the address
337 		 * corresponding to the outgoing interface
338 		 * unless it is the loopback (in case a route
339 		 * to our address on another net goes to loopback).
340 		 */
341 		if (ro->ro_rt && !(ro->ro_rt->rt_ifp->if_flags & IFF_LOOPBACK))
342 			ia = ifatoia(ro->ro_rt->rt_ifa);
343 		if (ia == 0) {
344 			u_short fport = sin->sin_port;
345 
346 			sin->sin_port = 0;
347 			ia = ifatoia(ifa_ifwithdstaddr(sintosa(sin)));
348 			if (ia == 0)
349 				ia = ifatoia(ifa_ifwithnet(sintosa(sin)));
350 			sin->sin_port = fport;
351 			if (ia == 0)
352 				ia = in_ifaddr;
353 			if (ia == 0)
354 				return (EADDRNOTAVAIL);
355 		}
356 		/*
357 		 * If the destination address is multicast and an outgoing
358 		 * interface has been set as a multicast option, use the
359 		 * address of that interface as our source address.
360 		 */
361 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr)) &&
362 		    inp->inp_moptions != NULL) {
363 			struct ip_moptions *imo;
364 			struct ifnet *ifp;
365 
366 			imo = inp->inp_moptions;
367 			if (imo->imo_multicast_ifp != NULL) {
368 				ifp = imo->imo_multicast_ifp;
369 				for (ia = in_ifaddr; ia; ia = ia->ia_next)
370 					if (ia->ia_ifp == ifp)
371 						break;
372 				if (ia == 0)
373 					return (EADDRNOTAVAIL);
374 			}
375 		}
376 	/*
377 	 * Don't do pcblookup call here; return interface in plocal_sin
378 	 * and exit to caller, that will do the lookup.
379 	 */
380 		*plocal_sin = &ia->ia_addr;
381 
382 	}
383 	return(0);
384 }
385 
386 /*
387  * Outer subroutine:
388  * Connect from a socket to a specified address.
389  * Both address and port must be specified in argument sin.
390  * If don't have a local address for this socket yet,
391  * then pick one.
392  */
393 int
394 in_pcbconnect(inp, nam)
395 	register struct inpcb *inp;
396 	struct mbuf *nam;
397 {
398 	struct sockaddr_in *ifaddr;
399 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
400 	int error;
401 
402 	/*
403 	 *   Call inner routine, to assign local interface address.
404 	 */
405 	if (error = in_pcbladdr(inp, nam, &ifaddr))
406 		return(error);
407 
408 	if (in_pcblookuphash(inp->inp_pcbinfo, sin->sin_addr, sin->sin_port,
409 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
410 	    inp->inp_lport, 0) != NULL)
411 		return (EADDRINUSE);
412 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
413 		if (inp->inp_lport == 0)
414 			(void)in_pcbbind(inp, (struct mbuf *)0);
415 		inp->inp_laddr = ifaddr->sin_addr;
416 	}
417 	inp->inp_faddr = sin->sin_addr;
418 	inp->inp_fport = sin->sin_port;
419 	in_pcbrehash(inp);
420 	return (0);
421 }
422 
423 void
424 in_pcbdisconnect(inp)
425 	struct inpcb *inp;
426 {
427 
428 	inp->inp_faddr.s_addr = INADDR_ANY;
429 	inp->inp_fport = 0;
430 	in_pcbrehash(inp);
431 	if (inp->inp_socket->so_state & SS_NOFDREF)
432 		in_pcbdetach(inp);
433 }
434 
435 void
436 in_pcbdetach(inp)
437 	struct inpcb *inp;
438 {
439 	struct socket *so = inp->inp_socket;
440 	int s;
441 
442 	so->so_pcb = 0;
443 	sofree(so);
444 	if (inp->inp_options)
445 		(void)m_free(inp->inp_options);
446 	if (inp->inp_route.ro_rt)
447 		rtfree(inp->inp_route.ro_rt);
448 	ip_freemoptions(inp->inp_moptions);
449 	s = splnet();
450 	LIST_REMOVE(inp, inp_hash);
451 	LIST_REMOVE(inp, inp_list);
452 	splx(s);
453 	FREE(inp, M_PCB);
454 }
455 
456 void
457 in_setsockaddr(inp, nam)
458 	register struct inpcb *inp;
459 	struct mbuf *nam;
460 {
461 	register struct sockaddr_in *sin;
462 
463 	nam->m_len = sizeof (*sin);
464 	sin = mtod(nam, struct sockaddr_in *);
465 	bzero((caddr_t)sin, sizeof (*sin));
466 	sin->sin_family = AF_INET;
467 	sin->sin_len = sizeof(*sin);
468 	sin->sin_port = inp->inp_lport;
469 	sin->sin_addr = inp->inp_laddr;
470 }
471 
472 void
473 in_setpeeraddr(inp, nam)
474 	struct inpcb *inp;
475 	struct mbuf *nam;
476 {
477 	register struct sockaddr_in *sin;
478 
479 	nam->m_len = sizeof (*sin);
480 	sin = mtod(nam, struct sockaddr_in *);
481 	bzero((caddr_t)sin, sizeof (*sin));
482 	sin->sin_family = AF_INET;
483 	sin->sin_len = sizeof(*sin);
484 	sin->sin_port = inp->inp_fport;
485 	sin->sin_addr = inp->inp_faddr;
486 }
487 
488 /*
489  * Pass some notification to all connections of a protocol
490  * associated with address dst.  The local address and/or port numbers
491  * may be specified to limit the search.  The "usual action" will be
492  * taken, depending on the ctlinput cmd.  The caller must filter any
493  * cmds that are uninteresting (e.g., no error in the map).
494  * Call the protocol specific routine (if any) to report
495  * any errors for each matching socket.
496  *
497  * Must be called at splnet.
498  */
499 void
500 in_pcbnotify(head, dst, fport_arg, laddr, lport_arg, cmd, notify)
501 	struct inpcbhead *head;
502 	struct sockaddr *dst;
503 	u_int fport_arg, lport_arg;
504 	struct in_addr laddr;
505 	int cmd;
506 	void (*notify) __P((struct inpcb *, int));
507 {
508 	register struct inpcb *inp, *oinp;
509 	struct in_addr faddr;
510 	u_short fport = fport_arg, lport = lport_arg;
511 	int errno, s;
512 
513 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET)
514 		return;
515 	faddr = ((struct sockaddr_in *)dst)->sin_addr;
516 	if (faddr.s_addr == INADDR_ANY)
517 		return;
518 
519 	/*
520 	 * Redirects go to all references to the destination,
521 	 * and use in_rtchange to invalidate the route cache.
522 	 * Dead host indications: notify all references to the destination.
523 	 * Otherwise, if we have knowledge of the local port and address,
524 	 * deliver only to that socket.
525 	 */
526 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
527 		fport = 0;
528 		lport = 0;
529 		laddr.s_addr = 0;
530 		if (cmd != PRC_HOSTDEAD)
531 			notify = in_rtchange;
532 	}
533 	errno = inetctlerrmap[cmd];
534 	s = splnet();
535 	for (inp = head->lh_first; inp != NULL;) {
536 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
537 		    inp->inp_socket == 0 ||
538 		    (lport && inp->inp_lport != lport) ||
539 		    (laddr.s_addr && inp->inp_laddr.s_addr != laddr.s_addr) ||
540 		    (fport && inp->inp_fport != fport)) {
541 			inp = inp->inp_list.le_next;
542 			continue;
543 		}
544 		oinp = inp;
545 		inp = inp->inp_list.le_next;
546 		if (notify)
547 			(*notify)(oinp, errno);
548 	}
549 	splx(s);
550 }
551 
552 /*
553  * Check for alternatives when higher level complains
554  * about service problems.  For now, invalidate cached
555  * routing information.  If the route was created dynamically
556  * (by a redirect), time to try a default gateway again.
557  */
558 void
559 in_losing(inp)
560 	struct inpcb *inp;
561 {
562 	register struct rtentry *rt;
563 	struct rt_addrinfo info;
564 
565 	if ((rt = inp->inp_route.ro_rt)) {
566 		inp->inp_route.ro_rt = 0;
567 		bzero((caddr_t)&info, sizeof(info));
568 		info.rti_info[RTAX_DST] =
569 			(struct sockaddr *)&inp->inp_route.ro_dst;
570 		info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
571 		info.rti_info[RTAX_NETMASK] = rt_mask(rt);
572 		rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
573 		if (rt->rt_flags & RTF_DYNAMIC)
574 			(void) rtrequest(RTM_DELETE, rt_key(rt),
575 				rt->rt_gateway, rt_mask(rt), rt->rt_flags,
576 				(struct rtentry **)0);
577 		else
578 		/*
579 		 * A new route can be allocated
580 		 * the next time output is attempted.
581 		 */
582 			rtfree(rt);
583 	}
584 }
585 
586 /*
587  * After a routing change, flush old routing
588  * and allocate a (hopefully) better one.
589  */
590 static void
591 in_rtchange(inp, errno)
592 	register struct inpcb *inp;
593 	int errno;
594 {
595 	if (inp->inp_route.ro_rt) {
596 		rtfree(inp->inp_route.ro_rt);
597 		inp->inp_route.ro_rt = 0;
598 		/*
599 		 * A new route can be allocated the next time
600 		 * output is attempted.
601 		 */
602 	}
603 }
604 
605 struct inpcb *
606 in_pcblookup(pcbinfo, faddr, fport_arg, laddr, lport_arg, wild_okay)
607 	struct inpcbinfo *pcbinfo;
608 	struct in_addr faddr, laddr;
609 	u_int fport_arg, lport_arg;
610 	int wild_okay;
611 {
612 	register struct inpcb *inp, *match = NULL;
613 	int matchwild = 3, wildcard;
614 	u_short fport = fport_arg, lport = lport_arg;
615 	int s;
616 
617 	s = splnet();
618 
619 	for (inp = pcbinfo->listhead->lh_first; inp != NULL; inp = inp->inp_list.le_next) {
620 		if (inp->inp_lport != lport)
621 			continue;
622 		wildcard = 0;
623 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
624 			if (faddr.s_addr == INADDR_ANY)
625 				wildcard++;
626 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
627 			    inp->inp_fport != fport)
628 				continue;
629 		} else {
630 			if (faddr.s_addr != INADDR_ANY)
631 				wildcard++;
632 		}
633 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
634 			if (laddr.s_addr == INADDR_ANY)
635 				wildcard++;
636 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
637 				continue;
638 		} else {
639 			if (laddr.s_addr != INADDR_ANY)
640 				wildcard++;
641 		}
642 		if (wildcard && wild_okay == 0)
643 			continue;
644 		if (wildcard < matchwild) {
645 			match = inp;
646 			matchwild = wildcard;
647 			if (matchwild == 0) {
648 				break;
649 			}
650 		}
651 	}
652 	splx(s);
653 	return (match);
654 }
655 
656 /*
657  * Lookup PCB in hash list.
658  */
659 struct inpcb *
660 in_pcblookuphash(pcbinfo, faddr, fport_arg, laddr, lport_arg, wildcard)
661 	struct inpcbinfo *pcbinfo;
662 	struct in_addr faddr, laddr;
663 	u_int fport_arg, lport_arg;
664 	int wildcard;
665 {
666 	struct inpcbhead *head;
667 	register struct inpcb *inp;
668 	u_short fport = fport_arg, lport = lport_arg;
669 	int s;
670 
671 	s = splnet();
672 	/*
673 	 * First look for an exact match.
674 	 */
675 	head = &pcbinfo->hashbase[(faddr.s_addr + lport + fport) % pcbinfo->hashsize];
676 	for (inp = head->lh_first; inp != NULL; inp = inp->inp_hash.le_next) {
677 		if (inp->inp_faddr.s_addr == faddr.s_addr &&
678 		    inp->inp_fport == fport && inp->inp_lport == lport &&
679 		    inp->inp_laddr.s_addr == laddr.s_addr)
680 			goto found;
681 	}
682 	if (wildcard) {
683 		struct inpcb *local_wild = NULL;
684 
685 		head = &pcbinfo->hashbase[(INADDR_ANY + lport) % pcbinfo->hashsize];
686 		for (inp = head->lh_first; inp != NULL; inp = inp->inp_hash.le_next) {
687 			if (inp->inp_faddr.s_addr == INADDR_ANY &&
688 			    inp->inp_fport == 0 && inp->inp_lport == lport) {
689 				if (inp->inp_laddr.s_addr == laddr.s_addr)
690 					goto found;
691 				else if (inp->inp_laddr.s_addr == INADDR_ANY)
692 					local_wild = inp;
693 			}
694 		}
695 		if (local_wild != NULL) {
696 			inp = local_wild;
697 			goto found;
698 		}
699 	}
700 	splx(s);
701 	return (NULL);
702 
703 found:
704 	/*
705 	 * Move PCB to head of this hash chain so that it can be
706 	 * found more quickly in the future.
707 	 * XXX - this is a pessimization on machines with few
708 	 * concurrent connections.
709 	 */
710 	if (inp != head->lh_first) {
711 		LIST_REMOVE(inp, inp_hash);
712 		LIST_INSERT_HEAD(head, inp, inp_hash);
713 	}
714 	splx(s);
715 	return (inp);
716 }
717 
718 /*
719  * Insert PCB into hash chain. Must be called at splnet.
720  */
721 static void
722 in_pcbinshash(inp)
723 	struct inpcb *inp;
724 {
725 	struct inpcbhead *head;
726 
727 	head = &inp->inp_pcbinfo->hashbase[(inp->inp_faddr.s_addr +
728 		inp->inp_lport + inp->inp_fport) % inp->inp_pcbinfo->hashsize];
729 
730 	LIST_INSERT_HEAD(head, inp, inp_hash);
731 }
732 
733 void
734 in_pcbrehash(inp)
735 	struct inpcb *inp;
736 {
737 	struct inpcbhead *head;
738 	int s;
739 
740 	s = splnet();
741 	LIST_REMOVE(inp, inp_hash);
742 
743 	head = &inp->inp_pcbinfo->hashbase[(inp->inp_faddr.s_addr +
744 		inp->inp_lport + inp->inp_fport) % inp->inp_pcbinfo->hashsize];
745 
746 	LIST_INSERT_HEAD(head, inp, inp_hash);
747 	splx(s);
748 }
749