xref: /freebsd/sys/netinet/in_pcb.c (revision afe61c15161c324a7af299a9b8457aba5afc92db)
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  */
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/malloc.h>
39 #include <sys/mbuf.h>
40 #include <sys/protosw.h>
41 #include <sys/socket.h>
42 #include <sys/socketvar.h>
43 #include <sys/ioctl.h>
44 #include <sys/errno.h>
45 #include <sys/time.h>
46 #include <sys/proc.h>
47 
48 #include <net/if.h>
49 #include <net/route.h>
50 
51 #include <netinet/in.h>
52 #include <netinet/in_systm.h>
53 #include <netinet/ip.h>
54 #include <netinet/in_pcb.h>
55 #include <netinet/in_var.h>
56 #include <netinet/ip_var.h>
57 
58 struct	in_addr zeroin_addr;
59 
60 int
61 in_pcballoc(so, head)
62 	struct socket *so;
63 	struct inpcb *head;
64 {
65 	register struct inpcb *inp;
66 
67 	MALLOC(inp, struct inpcb *, sizeof(*inp), M_PCB, M_WAITOK);
68 	if (inp == NULL)
69 		return (ENOBUFS);
70 	bzero((caddr_t)inp, sizeof(*inp));
71 	inp->inp_head = head;
72 	inp->inp_socket = so;
73 	insque(inp, head);
74 	so->so_pcb = (caddr_t)inp;
75 	return (0);
76 }
77 
78 int
79 in_pcbbind(inp, nam)
80 	register struct inpcb *inp;
81 	struct mbuf *nam;
82 {
83 	register struct socket *so = inp->inp_socket;
84 	register struct inpcb *head = inp->inp_head;
85 	register struct sockaddr_in *sin;
86 	struct proc *p = curproc;		/* XXX */
87 	u_short lport = 0;
88 	int wild = 0, reuseport = (so->so_options & SO_REUSEPORT);
89 	int error;
90 
91 	if (in_ifaddr == 0)
92 		return (EADDRNOTAVAIL);
93 	if (inp->inp_lport || inp->inp_laddr.s_addr != INADDR_ANY)
94 		return (EINVAL);
95 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0 &&
96 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
97 	     (so->so_options & SO_ACCEPTCONN) == 0))
98 		wild = INPLOOKUP_WILDCARD;
99 	if (nam) {
100 		sin = mtod(nam, struct sockaddr_in *);
101 		if (nam->m_len != sizeof (*sin))
102 			return (EINVAL);
103 #ifdef notdef
104 		/*
105 		 * We should check the family, but old programs
106 		 * incorrectly fail to initialize it.
107 		 */
108 		if (sin->sin_family != AF_INET)
109 			return (EAFNOSUPPORT);
110 #endif
111 		lport = sin->sin_port;
112 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr))) {
113 			/*
114 			 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
115 			 * allow complete duplication of binding if
116 			 * SO_REUSEPORT is set, or if SO_REUSEADDR is set
117 			 * and a multicast address is bound on both
118 			 * new and duplicated sockets.
119 			 */
120 			if (so->so_options & SO_REUSEADDR)
121 				reuseport = SO_REUSEADDR|SO_REUSEPORT;
122 		} else if (sin->sin_addr.s_addr != INADDR_ANY) {
123 			sin->sin_port = 0;		/* yech... */
124 			if (ifa_ifwithaddr((struct sockaddr *)sin) == 0)
125 				return (EADDRNOTAVAIL);
126 		}
127 		if (lport) {
128 			struct inpcb *t;
129 
130 			/* GROSS */
131 			if (ntohs(lport) < IPPORT_RESERVED &&
132 			    (error = suser(p->p_ucred, &p->p_acflag)))
133 				return (error);
134 			t = in_pcblookup(head, zeroin_addr, 0,
135 			    sin->sin_addr, lport, wild);
136 			if (t && (reuseport & t->inp_socket->so_options) == 0)
137 				return (EADDRINUSE);
138 		}
139 		inp->inp_laddr = sin->sin_addr;
140 	}
141 	if (lport == 0)
142 		do {
143 			if (head->inp_lport++ < IPPORT_RESERVED ||
144 			    head->inp_lport > IPPORT_USERRESERVED)
145 				head->inp_lport = IPPORT_RESERVED;
146 			lport = htons(head->inp_lport);
147 		} while (in_pcblookup(head,
148 			    zeroin_addr, 0, inp->inp_laddr, lport, wild));
149 	inp->inp_lport = lport;
150 	return (0);
151 }
152 
153 /*
154  * Connect from a socket to a specified address.
155  * Both address and port must be specified in argument sin.
156  * If don't have a local address for this socket yet,
157  * then pick one.
158  */
159 int
160 in_pcbconnect(inp, nam)
161 	register struct inpcb *inp;
162 	struct mbuf *nam;
163 {
164 	struct in_ifaddr *ia;
165 	struct sockaddr_in *ifaddr = 0;
166 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
167 
168 	if (nam->m_len != sizeof (*sin))
169 		return (EINVAL);
170 	if (sin->sin_family != AF_INET)
171 		return (EAFNOSUPPORT);
172 	if (sin->sin_port == 0)
173 		return (EADDRNOTAVAIL);
174 	if (in_ifaddr) {
175 		/*
176 		 * If the destination address is INADDR_ANY,
177 		 * use the primary local address.
178 		 * If the supplied address is INADDR_BROADCAST,
179 		 * and the primary interface supports broadcast,
180 		 * choose the broadcast address for that interface.
181 		 */
182 #define	satosin(sa)	((struct sockaddr_in *)(sa))
183 #define sintosa(sin)	((struct sockaddr *)(sin))
184 #define ifatoia(ifa)	((struct in_ifaddr *)(ifa))
185 		if (sin->sin_addr.s_addr == INADDR_ANY)
186 		    sin->sin_addr = IA_SIN(in_ifaddr)->sin_addr;
187 		else if (sin->sin_addr.s_addr == (u_long)INADDR_BROADCAST &&
188 		  (in_ifaddr->ia_ifp->if_flags & IFF_BROADCAST))
189 		    sin->sin_addr = satosin(&in_ifaddr->ia_broadaddr)->sin_addr;
190 	}
191 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
192 		register struct route *ro;
193 
194 		ia = (struct in_ifaddr *)0;
195 		/*
196 		 * If route is known or can be allocated now,
197 		 * our src addr is taken from the i/f, else punt.
198 		 */
199 		ro = &inp->inp_route;
200 		if (ro->ro_rt &&
201 		    (satosin(&ro->ro_dst)->sin_addr.s_addr !=
202 			sin->sin_addr.s_addr ||
203 		    inp->inp_socket->so_options & SO_DONTROUTE)) {
204 			RTFREE(ro->ro_rt);
205 			ro->ro_rt = (struct rtentry *)0;
206 		}
207 		if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0 && /*XXX*/
208 		    (ro->ro_rt == (struct rtentry *)0 ||
209 		    ro->ro_rt->rt_ifp == (struct ifnet *)0)) {
210 			/* No route yet, so try to acquire one */
211 			ro->ro_dst.sa_family = AF_INET;
212 			ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
213 			((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
214 				sin->sin_addr;
215 			rtalloc(ro);
216 		}
217 		/*
218 		 * If we found a route, use the address
219 		 * corresponding to the outgoing interface
220 		 * unless it is the loopback (in case a route
221 		 * to our address on another net goes to loopback).
222 		 */
223 		if (ro->ro_rt && !(ro->ro_rt->rt_ifp->if_flags & IFF_LOOPBACK))
224 			ia = ifatoia(ro->ro_rt->rt_ifa);
225 		if (ia == 0) {
226 			u_short fport = sin->sin_port;
227 
228 			sin->sin_port = 0;
229 			ia = ifatoia(ifa_ifwithdstaddr(sintosa(sin)));
230 			if (ia == 0)
231 				ia = ifatoia(ifa_ifwithnet(sintosa(sin)));
232 			sin->sin_port = fport;
233 			if (ia == 0)
234 				ia = in_ifaddr;
235 			if (ia == 0)
236 				return (EADDRNOTAVAIL);
237 		}
238 		/*
239 		 * If the destination address is multicast and an outgoing
240 		 * interface has been set as a multicast option, use the
241 		 * address of that interface as our source address.
242 		 */
243 		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr)) &&
244 		    inp->inp_moptions != NULL) {
245 			struct ip_moptions *imo;
246 			struct ifnet *ifp;
247 
248 			imo = inp->inp_moptions;
249 			if (imo->imo_multicast_ifp != NULL) {
250 				ifp = imo->imo_multicast_ifp;
251 				for (ia = in_ifaddr; ia; ia = ia->ia_next)
252 					if (ia->ia_ifp == ifp)
253 						break;
254 				if (ia == 0)
255 					return (EADDRNOTAVAIL);
256 			}
257 		}
258 		ifaddr = (struct sockaddr_in *)&ia->ia_addr;
259 	}
260 	if (in_pcblookup(inp->inp_head,
261 	    sin->sin_addr,
262 	    sin->sin_port,
263 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
264 	    inp->inp_lport,
265 	    0))
266 		return (EADDRINUSE);
267 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
268 		if (inp->inp_lport == 0)
269 			(void)in_pcbbind(inp, (struct mbuf *)0);
270 		inp->inp_laddr = ifaddr->sin_addr;
271 	}
272 	inp->inp_faddr = sin->sin_addr;
273 	inp->inp_fport = sin->sin_port;
274 	return (0);
275 }
276 
277 void
278 in_pcbdisconnect(inp)
279 	struct inpcb *inp;
280 {
281 
282 	inp->inp_faddr.s_addr = INADDR_ANY;
283 	inp->inp_fport = 0;
284 	if (inp->inp_socket->so_state & SS_NOFDREF)
285 		in_pcbdetach(inp);
286 }
287 
288 void
289 in_pcbdetach(inp)
290 	struct inpcb *inp;
291 {
292 	struct socket *so = inp->inp_socket;
293 
294 	so->so_pcb = 0;
295 	sofree(so);
296 	if (inp->inp_options)
297 		(void)m_free(inp->inp_options);
298 	if (inp->inp_route.ro_rt)
299 		rtfree(inp->inp_route.ro_rt);
300 	ip_freemoptions(inp->inp_moptions);
301 	remque(inp);
302 	FREE(inp, M_PCB);
303 }
304 
305 void
306 in_setsockaddr(inp, nam)
307 	register struct inpcb *inp;
308 	struct mbuf *nam;
309 {
310 	register struct sockaddr_in *sin;
311 
312 	nam->m_len = sizeof (*sin);
313 	sin = mtod(nam, struct sockaddr_in *);
314 	bzero((caddr_t)sin, sizeof (*sin));
315 	sin->sin_family = AF_INET;
316 	sin->sin_len = sizeof(*sin);
317 	sin->sin_port = inp->inp_lport;
318 	sin->sin_addr = inp->inp_laddr;
319 }
320 
321 void
322 in_setpeeraddr(inp, nam)
323 	struct inpcb *inp;
324 	struct mbuf *nam;
325 {
326 	register struct sockaddr_in *sin;
327 
328 	nam->m_len = sizeof (*sin);
329 	sin = mtod(nam, struct sockaddr_in *);
330 	bzero((caddr_t)sin, sizeof (*sin));
331 	sin->sin_family = AF_INET;
332 	sin->sin_len = sizeof(*sin);
333 	sin->sin_port = inp->inp_fport;
334 	sin->sin_addr = inp->inp_faddr;
335 }
336 
337 /*
338  * Pass some notification to all connections of a protocol
339  * associated with address dst.  The local address and/or port numbers
340  * may be specified to limit the search.  The "usual action" will be
341  * taken, depending on the ctlinput cmd.  The caller must filter any
342  * cmds that are uninteresting (e.g., no error in the map).
343  * Call the protocol specific routine (if any) to report
344  * any errors for each matching socket.
345  *
346  * Must be called at splnet.
347  */
348 void
349 in_pcbnotify(head, dst, fport_arg, laddr, lport_arg, cmd, notify)
350 	struct inpcb *head;
351 	struct sockaddr *dst;
352 	u_int fport_arg, lport_arg;
353 	struct in_addr laddr;
354 	int cmd;
355 	void (*notify) __P((struct inpcb *, int));
356 {
357 	extern u_char inetctlerrmap[];
358 	register struct inpcb *inp, *oinp;
359 	struct in_addr faddr;
360 	u_short fport = fport_arg, lport = lport_arg;
361 	int errno;
362 
363 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET)
364 		return;
365 	faddr = ((struct sockaddr_in *)dst)->sin_addr;
366 	if (faddr.s_addr == INADDR_ANY)
367 		return;
368 
369 	/*
370 	 * Redirects go to all references to the destination,
371 	 * and use in_rtchange to invalidate the route cache.
372 	 * Dead host indications: notify all references to the destination.
373 	 * Otherwise, if we have knowledge of the local port and address,
374 	 * deliver only to that socket.
375 	 */
376 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
377 		fport = 0;
378 		lport = 0;
379 		laddr.s_addr = 0;
380 		if (cmd != PRC_HOSTDEAD)
381 			notify = in_rtchange;
382 	}
383 	errno = inetctlerrmap[cmd];
384 	for (inp = head->inp_next; inp != head;) {
385 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
386 		    inp->inp_socket == 0 ||
387 		    (lport && inp->inp_lport != lport) ||
388 		    (laddr.s_addr && inp->inp_laddr.s_addr != laddr.s_addr) ||
389 		    (fport && inp->inp_fport != fport)) {
390 			inp = inp->inp_next;
391 			continue;
392 		}
393 		oinp = inp;
394 		inp = inp->inp_next;
395 		if (notify)
396 			(*notify)(oinp, errno);
397 	}
398 }
399 
400 /*
401  * Check for alternatives when higher level complains
402  * about service problems.  For now, invalidate cached
403  * routing information.  If the route was created dynamically
404  * (by a redirect), time to try a default gateway again.
405  */
406 void
407 in_losing(inp)
408 	struct inpcb *inp;
409 {
410 	register struct rtentry *rt;
411 	struct rt_addrinfo info;
412 
413 	if ((rt = inp->inp_route.ro_rt)) {
414 		inp->inp_route.ro_rt = 0;
415 		bzero((caddr_t)&info, sizeof(info));
416 		info.rti_info[RTAX_DST] =
417 			(struct sockaddr *)&inp->inp_route.ro_dst;
418 		info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
419 		info.rti_info[RTAX_NETMASK] = rt_mask(rt);
420 		rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
421 		if (rt->rt_flags & RTF_DYNAMIC)
422 			(void) rtrequest(RTM_DELETE, rt_key(rt),
423 				rt->rt_gateway, rt_mask(rt), rt->rt_flags,
424 				(struct rtentry **)0);
425 		else
426 		/*
427 		 * A new route can be allocated
428 		 * the next time output is attempted.
429 		 */
430 			rtfree(rt);
431 	}
432 }
433 
434 /*
435  * After a routing change, flush old routing
436  * and allocate a (hopefully) better one.
437  */
438 void
439 in_rtchange(inp, errno)
440 	register struct inpcb *inp;
441 	int errno;
442 {
443 	if (inp->inp_route.ro_rt) {
444 		rtfree(inp->inp_route.ro_rt);
445 		inp->inp_route.ro_rt = 0;
446 		/*
447 		 * A new route can be allocated the next time
448 		 * output is attempted.
449 		 */
450 	}
451 }
452 
453 struct inpcb *
454 in_pcblookup(head, faddr, fport_arg, laddr, lport_arg, flags)
455 	struct inpcb *head;
456 	struct in_addr faddr, laddr;
457 	u_int fport_arg, lport_arg;
458 	int flags;
459 {
460 	register struct inpcb *inp, *match = 0;
461 	int matchwild = 3, wildcard;
462 	u_short fport = fport_arg, lport = lport_arg;
463 
464 	for (inp = head->inp_next; inp != head; inp = inp->inp_next) {
465 		if (inp->inp_lport != lport)
466 			continue;
467 		wildcard = 0;
468 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
469 			if (laddr.s_addr == INADDR_ANY)
470 				wildcard++;
471 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
472 				continue;
473 		} else {
474 			if (laddr.s_addr != INADDR_ANY)
475 				wildcard++;
476 		}
477 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
478 			if (faddr.s_addr == INADDR_ANY)
479 				wildcard++;
480 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
481 			    inp->inp_fport != fport)
482 				continue;
483 		} else {
484 			if (faddr.s_addr != INADDR_ANY)
485 				wildcard++;
486 		}
487 		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
488 			continue;
489 		if (wildcard < matchwild) {
490 			match = inp;
491 			matchwild = wildcard;
492 			if (matchwild == 0)
493 				break;
494 		}
495 	}
496 	return (match);
497 }
498