xref: /freebsd/sys/netinet/in_pcb.c (revision 0c43d89a0d8e976ca494d4837f4c1f3734d2c300)
1 /*
2  * Copyright (c) 1982, 1986, 1991, 1993
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	8.2 (Berkeley) 1/4/94
34  * $Id$
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 
49 #include <net/if.h>
50 #include <net/route.h>
51 
52 #include <netinet/in.h>
53 #include <netinet/in_systm.h>
54 #include <netinet/ip.h>
55 #include <netinet/in_pcb.h>
56 #include <netinet/in_var.h>
57 #include <netinet/ip_var.h>
58 
59 struct	in_addr zeroin_addr;
60 
61 int
62 in_pcballoc(so, head)
63 	struct socket *so;
64 	struct inpcb *head;
65 {
66 	register struct inpcb *inp;
67 
68 	MALLOC(inp, struct inpcb *, sizeof(*inp), M_PCB, M_WAITOK);
69 	if (inp == NULL)
70 		return (ENOBUFS);
71 	bzero((caddr_t)inp, sizeof(*inp));
72 	inp->inp_head = head;
73 	inp->inp_socket = so;
74 	insque(inp, head);
75 	so->so_pcb = (caddr_t)inp;
76 	return (0);
77 }
78 
79 int
80 in_pcbbind(inp, nam)
81 	register struct inpcb *inp;
82 	struct mbuf *nam;
83 {
84 	register struct socket *so = inp->inp_socket;
85 	register struct inpcb *head = inp->inp_head;
86 	register struct sockaddr_in *sin;
87 	struct proc *p = curproc;		/* XXX */
88 	u_short lport = 0;
89 	int wild = 0, reuseport = (so->so_options & SO_REUSEPORT);
90 	int error;
91 
92 	if (in_ifaddr == 0)
93 		return (EADDRNOTAVAIL);
94 	if (inp->inp_lport || inp->inp_laddr.s_addr != INADDR_ANY)
95 		return (EINVAL);
96 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0 &&
97 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
98 	     (so->so_options & SO_ACCEPTCONN) == 0))
99 		wild = INPLOOKUP_WILDCARD;
100 	if (nam) {
101 		sin = mtod(nam, struct sockaddr_in *);
102 		if (nam->m_len != sizeof (*sin))
103 			return (EINVAL);
104 #ifdef notdef
105 		/*
106 		 * We should check the family, but old programs
107 		 * incorrectly fail to initialize it.
108 		 */
109 		if (sin->sin_family != AF_INET)
110 			return (EAFNOSUPPORT);
111 #endif
112 		lport = sin->sin_port;
113 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) {
114 			/*
115 			 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
116 			 * allow complete duplication of binding if
117 			 * SO_REUSEPORT is set, or if SO_REUSEADDR is set
118 			 * and a multicast address is bound on both
119 			 * new and duplicated sockets.
120 			 */
121 			if (so->so_options & SO_REUSEADDR)
122 				reuseport = SO_REUSEADDR|SO_REUSEPORT;
123 		} else if (sin->sin_addr.s_addr != INADDR_ANY) {
124 			sin->sin_port = 0;		/* yech... */
125 			if (ifa_ifwithaddr((struct sockaddr *)sin) == 0)
126 				return (EADDRNOTAVAIL);
127 		}
128 		if (lport) {
129 			struct inpcb *t;
130 
131 			/* GROSS */
132 			if (ntohs(lport) < IPPORT_RESERVED &&
133 			    (error = suser(p->p_ucred, &p->p_acflag)))
134 				return (error);
135 			t = in_pcblookup(head, zeroin_addr, 0,
136 			    sin->sin_addr, lport, wild);
137 			if (t && (reuseport & t->inp_socket->so_options) == 0)
138 				return (EADDRINUSE);
139 		}
140 		inp->inp_laddr = sin->sin_addr;
141 	}
142 	if (lport == 0)
143 		do {
144 			if (head->inp_lport++ < IPPORT_RESERVED ||
145 			    head->inp_lport > IPPORT_USERRESERVED)
146 				head->inp_lport = IPPORT_RESERVED;
147 			lport = htons(head->inp_lport);
148 		} while (in_pcblookup(head,
149 			    zeroin_addr, 0, inp->inp_laddr, lport, wild));
150 	inp->inp_lport = lport;
151 	return (0);
152 }
153 
154 /*
155  * Connect from a socket to a specified address.
156  * Both address and port must be specified in argument sin.
157  * If don't have a local address for this socket yet,
158  * then pick one.
159  */
160 int
161 in_pcbconnect(inp, nam)
162 	register struct inpcb *inp;
163 	struct mbuf *nam;
164 {
165 	struct in_ifaddr *ia;
166 	struct sockaddr_in *ifaddr = 0;
167 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
168 
169 	if (nam->m_len != sizeof (*sin))
170 		return (EINVAL);
171 	if (sin->sin_family != AF_INET)
172 		return (EAFNOSUPPORT);
173 	if (sin->sin_port == 0)
174 		return (EADDRNOTAVAIL);
175 	if (in_ifaddr) {
176 		/*
177 		 * If the destination address is INADDR_ANY,
178 		 * use the primary local address.
179 		 * If the supplied address is INADDR_BROADCAST,
180 		 * and the primary interface supports broadcast,
181 		 * choose the broadcast address for that interface.
182 		 */
183 #define	satosin(sa)	((struct sockaddr_in *)(sa))
184 #define sintosa(sin)	((struct sockaddr *)(sin))
185 #define ifatoia(ifa)	((struct in_ifaddr *)(ifa))
186 		if (sin->sin_addr.s_addr == INADDR_ANY)
187 		    sin->sin_addr = IA_SIN(in_ifaddr)->sin_addr;
188 		else if (sin->sin_addr.s_addr == (u_long)INADDR_BROADCAST &&
189 		  (in_ifaddr->ia_ifp->if_flags & IFF_BROADCAST))
190 		    sin->sin_addr = satosin(&in_ifaddr->ia_broadaddr)->sin_addr;
191 	}
192 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
193 		register struct route *ro;
194 
195 		ia = (struct in_ifaddr *)0;
196 		/*
197 		 * If route is known or can be allocated now,
198 		 * our src addr is taken from the i/f, else punt.
199 		 */
200 		ro = &inp->inp_route;
201 		if (ro->ro_rt &&
202 		    (satosin(&ro->ro_dst)->sin_addr.s_addr !=
203 			sin->sin_addr.s_addr ||
204 		    inp->inp_socket->so_options & SO_DONTROUTE)) {
205 			RTFREE(ro->ro_rt);
206 			ro->ro_rt = (struct rtentry *)0;
207 		}
208 		if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0 && /*XXX*/
209 		    (ro->ro_rt == (struct rtentry *)0 ||
210 		    ro->ro_rt->rt_ifp == (struct ifnet *)0)) {
211 			/* No route yet, so try to acquire one */
212 			ro->ro_dst.sa_family = AF_INET;
213 			ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
214 			((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
215 				sin->sin_addr;
216 			rtalloc(ro);
217 		}
218 		/*
219 		 * If we found a route, use the address
220 		 * corresponding to the outgoing interface
221 		 * unless it is the loopback (in case a route
222 		 * to our address on another net goes to loopback).
223 		 */
224 		if (ro->ro_rt && !(ro->ro_rt->rt_ifp->if_flags & IFF_LOOPBACK))
225 			ia = ifatoia(ro->ro_rt->rt_ifa);
226 		if (ia == 0) {
227 			u_short fport = sin->sin_port;
228 
229 			sin->sin_port = 0;
230 			ia = ifatoia(ifa_ifwithdstaddr(sintosa(sin)));
231 			if (ia == 0)
232 				ia = ifatoia(ifa_ifwithnet(sintosa(sin)));
233 			sin->sin_port = fport;
234 			if (ia == 0)
235 				ia = in_ifaddr;
236 			if (ia == 0)
237 				return (EADDRNOTAVAIL);
238 		}
239 		/*
240 		 * If the destination address is multicast and an outgoing
241 		 * interface has been set as a multicast option, use the
242 		 * address of that interface as our source address.
243 		 */
244 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr)) &&
245 		    inp->inp_moptions != NULL) {
246 			struct ip_moptions *imo;
247 			struct ifnet *ifp;
248 
249 			imo = inp->inp_moptions;
250 			if (imo->imo_multicast_ifp != NULL) {
251 				ifp = imo->imo_multicast_ifp;
252 				for (ia = in_ifaddr; ia; ia = ia->ia_next)
253 					if (ia->ia_ifp == ifp)
254 						break;
255 				if (ia == 0)
256 					return (EADDRNOTAVAIL);
257 			}
258 		}
259 		ifaddr = (struct sockaddr_in *)&ia->ia_addr;
260 	}
261 	if (in_pcblookup(inp->inp_head,
262 	    sin->sin_addr,
263 	    sin->sin_port,
264 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
265 	    inp->inp_lport,
266 	    0))
267 		return (EADDRINUSE);
268 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
269 		if (inp->inp_lport == 0)
270 			(void)in_pcbbind(inp, (struct mbuf *)0);
271 		inp->inp_laddr = ifaddr->sin_addr;
272 	}
273 	inp->inp_faddr = sin->sin_addr;
274 	inp->inp_fport = sin->sin_port;
275 	return (0);
276 }
277 
278 void
279 in_pcbdisconnect(inp)
280 	struct inpcb *inp;
281 {
282 
283 	inp->inp_faddr.s_addr = INADDR_ANY;
284 	inp->inp_fport = 0;
285 	if (inp->inp_socket->so_state & SS_NOFDREF)
286 		in_pcbdetach(inp);
287 }
288 
289 void
290 in_pcbdetach(inp)
291 	struct inpcb *inp;
292 {
293 	struct socket *so = inp->inp_socket;
294 
295 	so->so_pcb = 0;
296 	sofree(so);
297 	if (inp->inp_options)
298 		(void)m_free(inp->inp_options);
299 	if (inp->inp_route.ro_rt)
300 		rtfree(inp->inp_route.ro_rt);
301 	ip_freemoptions(inp->inp_moptions);
302 	remque(inp);
303 	FREE(inp, M_PCB);
304 }
305 
306 void
307 in_setsockaddr(inp, nam)
308 	register struct inpcb *inp;
309 	struct mbuf *nam;
310 {
311 	register struct sockaddr_in *sin;
312 
313 	nam->m_len = sizeof (*sin);
314 	sin = mtod(nam, struct sockaddr_in *);
315 	bzero((caddr_t)sin, sizeof (*sin));
316 	sin->sin_family = AF_INET;
317 	sin->sin_len = sizeof(*sin);
318 	sin->sin_port = inp->inp_lport;
319 	sin->sin_addr = inp->inp_laddr;
320 }
321 
322 void
323 in_setpeeraddr(inp, nam)
324 	struct inpcb *inp;
325 	struct mbuf *nam;
326 {
327 	register struct sockaddr_in *sin;
328 
329 	nam->m_len = sizeof (*sin);
330 	sin = mtod(nam, struct sockaddr_in *);
331 	bzero((caddr_t)sin, sizeof (*sin));
332 	sin->sin_family = AF_INET;
333 	sin->sin_len = sizeof(*sin);
334 	sin->sin_port = inp->inp_fport;
335 	sin->sin_addr = inp->inp_faddr;
336 }
337 
338 /*
339  * Pass some notification to all connections of a protocol
340  * associated with address dst.  The local address and/or port numbers
341  * may be specified to limit the search.  The "usual action" will be
342  * taken, depending on the ctlinput cmd.  The caller must filter any
343  * cmds that are uninteresting (e.g., no error in the map).
344  * Call the protocol specific routine (if any) to report
345  * any errors for each matching socket.
346  *
347  * Must be called at splnet.
348  */
349 void
350 in_pcbnotify(head, dst, fport_arg, laddr, lport_arg, cmd, notify)
351 	struct inpcb *head;
352 	struct sockaddr *dst;
353 	u_int fport_arg, lport_arg;
354 	struct in_addr laddr;
355 	int cmd;
356 	void (*notify) __P((struct inpcb *, int));
357 {
358 	extern u_char inetctlerrmap[];
359 	register struct inpcb *inp, *oinp;
360 	struct in_addr faddr;
361 	u_short fport = fport_arg, lport = lport_arg;
362 	int errno;
363 
364 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET)
365 		return;
366 	faddr = ((struct sockaddr_in *)dst)->sin_addr;
367 	if (faddr.s_addr == INADDR_ANY)
368 		return;
369 
370 	/*
371 	 * Redirects go to all references to the destination,
372 	 * and use in_rtchange to invalidate the route cache.
373 	 * Dead host indications: notify all references to the destination.
374 	 * Otherwise, if we have knowledge of the local port and address,
375 	 * deliver only to that socket.
376 	 */
377 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
378 		fport = 0;
379 		lport = 0;
380 		laddr.s_addr = 0;
381 		if (cmd != PRC_HOSTDEAD)
382 			notify = in_rtchange;
383 	}
384 	errno = inetctlerrmap[cmd];
385 	for (inp = head->inp_next; inp != head;) {
386 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
387 		    inp->inp_socket == 0 ||
388 		    (lport && inp->inp_lport != lport) ||
389 		    (laddr.s_addr && inp->inp_laddr.s_addr != laddr.s_addr) ||
390 		    (fport && inp->inp_fport != fport)) {
391 			inp = inp->inp_next;
392 			continue;
393 		}
394 		oinp = inp;
395 		inp = inp->inp_next;
396 		if (notify)
397 			(*notify)(oinp, errno);
398 	}
399 }
400 
401 /*
402  * Check for alternatives when higher level complains
403  * about service problems.  For now, invalidate cached
404  * routing information.  If the route was created dynamically
405  * (by a redirect), time to try a default gateway again.
406  */
407 void
408 in_losing(inp)
409 	struct inpcb *inp;
410 {
411 	register struct rtentry *rt;
412 	struct rt_addrinfo info;
413 
414 	if ((rt = inp->inp_route.ro_rt)) {
415 		inp->inp_route.ro_rt = 0;
416 		bzero((caddr_t)&info, sizeof(info));
417 		info.rti_info[RTAX_DST] =
418 			(struct sockaddr *)&inp->inp_route.ro_dst;
419 		info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
420 		info.rti_info[RTAX_NETMASK] = rt_mask(rt);
421 		rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
422 		if (rt->rt_flags & RTF_DYNAMIC)
423 			(void) rtrequest(RTM_DELETE, rt_key(rt),
424 				rt->rt_gateway, rt_mask(rt), rt->rt_flags,
425 				(struct rtentry **)0);
426 		else
427 		/*
428 		 * A new route can be allocated
429 		 * the next time output is attempted.
430 		 */
431 			rtfree(rt);
432 	}
433 }
434 
435 /*
436  * After a routing change, flush old routing
437  * and allocate a (hopefully) better one.
438  */
439 void
440 in_rtchange(inp, errno)
441 	register struct inpcb *inp;
442 	int errno;
443 {
444 	if (inp->inp_route.ro_rt) {
445 		rtfree(inp->inp_route.ro_rt);
446 		inp->inp_route.ro_rt = 0;
447 		/*
448 		 * A new route can be allocated the next time
449 		 * output is attempted.
450 		 */
451 	}
452 }
453 
454 struct inpcb *
455 in_pcblookup(head, faddr, fport_arg, laddr, lport_arg, flags)
456 	struct inpcb *head;
457 	struct in_addr faddr, laddr;
458 	u_int fport_arg, lport_arg;
459 	int flags;
460 {
461 	register struct inpcb *inp, *match = 0;
462 	int matchwild = 3, wildcard;
463 	u_short fport = fport_arg, lport = lport_arg;
464 
465 	for (inp = head->inp_next; inp != head; inp = inp->inp_next) {
466 		if (inp->inp_lport != lport)
467 			continue;
468 		wildcard = 0;
469 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
470 			if (laddr.s_addr == INADDR_ANY)
471 				wildcard++;
472 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
473 				continue;
474 		} else {
475 			if (laddr.s_addr != INADDR_ANY)
476 				wildcard++;
477 		}
478 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
479 			if (faddr.s_addr == INADDR_ANY)
480 				wildcard++;
481 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
482 			    inp->inp_fport != fport)
483 				continue;
484 		} else {
485 			if (faddr.s_addr != INADDR_ANY)
486 				wildcard++;
487 		}
488 		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
489 			continue;
490 		if (wildcard < matchwild) {
491 			match = inp;
492 			matchwild = wildcard;
493 			if (matchwild == 0)
494 				break;
495 		}
496 	}
497 	return (match);
498 }
499