xref: /original-bsd/sys/netinet/in_pcb.c (revision 68549010)
1 /*
2  * Copyright (c) 1982, 1986, 1991 Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  *
7  *	@(#)in_pcb.c	7.18 (Berkeley) 03/21/92
8  */
9 
10 #include "param.h"
11 #include "systm.h"
12 #include "malloc.h"
13 #include "mbuf.h"
14 #include "protosw.h"
15 #include "socket.h"
16 #include "socketvar.h"
17 #include "ioctl.h"
18 #include "errno.h"
19 
20 #include "../net/if.h"
21 #include "../net/route.h"
22 
23 #include "in.h"
24 #include "in_systm.h"
25 #include "ip.h"
26 #include "in_pcb.h"
27 #include "in_var.h"
28 
29 struct	in_addr zeroin_addr;
30 
31 in_pcballoc(so, head)
32 	struct socket *so;
33 	struct inpcb *head;
34 {
35 	struct mbuf *m;
36 	register struct inpcb *inp;
37 
38 	m = m_getclr(M_DONTWAIT, MT_PCB);
39 	if (m == NULL)
40 		return (ENOBUFS);
41 	inp = mtod(m, struct inpcb *);
42 	inp->inp_head = head;
43 	inp->inp_socket = so;
44 	insque(inp, head);
45 	so->so_pcb = (caddr_t)inp;
46 	return (0);
47 }
48 
49 in_pcbbind(inp, nam)
50 	register struct inpcb *inp;
51 	struct mbuf *nam;
52 {
53 	register struct socket *so = inp->inp_socket;
54 	register struct inpcb *head = inp->inp_head;
55 	register struct sockaddr_in *sin;
56 	u_short lport = 0;
57 
58 	if (in_ifaddr == 0)
59 		return (EADDRNOTAVAIL);
60 	if (inp->inp_lport || inp->inp_laddr.s_addr != INADDR_ANY)
61 		return (EINVAL);
62 	if (nam == 0)
63 		goto noname;
64 	sin = mtod(nam, struct sockaddr_in *);
65 	if (nam->m_len != sizeof (*sin))
66 		return (EINVAL);
67 	if (sin->sin_addr.s_addr != INADDR_ANY) {
68 		int tport = sin->sin_port;
69 
70 		sin->sin_port = 0;		/* yech... */
71 		if (ifa_ifwithaddr((struct sockaddr *)sin) == 0)
72 			return (EADDRNOTAVAIL);
73 		sin->sin_port = tport;
74 	}
75 	lport = sin->sin_port;
76 	if (lport) {
77 		u_short aport = ntohs(lport);
78 		int wild = 0;
79 
80 		/* GROSS */
81 		if (aport < IPPORT_RESERVED && (so->so_state & SS_PRIV) == 0)
82 			return (EACCES);
83 		/* even GROSSER, but this is the Internet */
84 		if ((so->so_options & SO_REUSEADDR) == 0 &&
85 		    ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
86 		     (so->so_options & SO_ACCEPTCONN) == 0))
87 			wild = INPLOOKUP_WILDCARD;
88 		if (in_pcblookup(head,
89 		    zeroin_addr, 0, sin->sin_addr, lport, wild))
90 			return (EADDRINUSE);
91 	}
92 	inp->inp_laddr = sin->sin_addr;
93 noname:
94 	if (lport == 0)
95 		do {
96 			if (head->inp_lport++ < IPPORT_RESERVED ||
97 			    head->inp_lport > IPPORT_USERRESERVED)
98 				head->inp_lport = IPPORT_RESERVED;
99 			lport = htons(head->inp_lport);
100 		} while (in_pcblookup(head,
101 			    zeroin_addr, 0, inp->inp_laddr, lport, 0));
102 	inp->inp_lport = lport;
103 	return (0);
104 }
105 
106 /*
107  * Connect from a socket to a specified address.
108  * Both address and port must be specified in argument sin.
109  * If don't have a local address for this socket yet,
110  * then pick one.
111  */
112 in_pcbconnect(inp, nam)
113 	register struct inpcb *inp;
114 	struct mbuf *nam;
115 {
116 	struct in_ifaddr *ia;
117 	struct sockaddr_in *ifaddr;
118 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
119 
120 	if (nam->m_len != sizeof (*sin))
121 		return (EINVAL);
122 	if (sin->sin_family != AF_INET)
123 		return (EAFNOSUPPORT);
124 	if (sin->sin_port == 0)
125 		return (EADDRNOTAVAIL);
126 	if (in_ifaddr) {
127 		/*
128 		 * If the destination address is INADDR_ANY,
129 		 * use the primary local address.
130 		 * If the supplied address is INADDR_BROADCAST,
131 		 * and the primary interface supports broadcast,
132 		 * choose the broadcast address for that interface.
133 		 */
134 #define	satosin(sa)	((struct sockaddr_in *)(sa))
135 		if (sin->sin_addr.s_addr == INADDR_ANY)
136 		    sin->sin_addr = IA_SIN(in_ifaddr)->sin_addr;
137 		else if (sin->sin_addr.s_addr == (u_long)INADDR_BROADCAST &&
138 		  (in_ifaddr->ia_ifp->if_flags & IFF_BROADCAST))
139 		    sin->sin_addr = satosin(&in_ifaddr->ia_broadaddr)->sin_addr;
140 	}
141 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
142 		register struct route *ro;
143 		struct ifnet *ifp;
144 
145 		ia = (struct in_ifaddr *)0;
146 		/*
147 		 * If route is known or can be allocated now,
148 		 * our src addr is taken from the i/f, else punt.
149 		 */
150 		ro = &inp->inp_route;
151 		if (ro->ro_rt &&
152 		    (satosin(&ro->ro_dst)->sin_addr.s_addr !=
153 			sin->sin_addr.s_addr ||
154 		    inp->inp_socket->so_options & SO_DONTROUTE)) {
155 			RTFREE(ro->ro_rt);
156 			ro->ro_rt = (struct rtentry *)0;
157 		}
158 		if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0 && /*XXX*/
159 		    (ro->ro_rt == (struct rtentry *)0 ||
160 		    ro->ro_rt->rt_ifp == (struct ifnet *)0)) {
161 			/* No route yet, so try to acquire one */
162 			ro->ro_dst.sa_family = AF_INET;
163 			ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
164 			((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
165 				sin->sin_addr;
166 			rtalloc(ro);
167 		}
168 		/*
169 		 * If we found a route, use the address
170 		 * corresponding to the outgoing interface
171 		 * unless it is the loopback (in case a route
172 		 * to our address on another net goes to loopback).
173 		 */
174 		if (ro->ro_rt && (ifp = ro->ro_rt->rt_ifp) &&
175 		    (ifp->if_flags & IFF_LOOPBACK) == 0 &&
176 		    (ia = (struct in_ifaddr *)ro->ro_rt->rt_ifa) == 0)
177 			for (ia = in_ifaddr; ia; ia = ia->ia_next)
178 				if (ia->ia_ifp == ifp)
179 					break;
180 		if (ia == 0) {
181 			int fport = sin->sin_port;
182 
183 			sin->sin_port = 0;
184 			ia = (struct in_ifaddr *)
185 			    ifa_ifwithdstaddr((struct sockaddr *)sin);
186 			sin->sin_port = fport;
187 			if (ia == 0)
188 				ia = in_iaonnetof(in_netof(sin->sin_addr));
189 			if (ia == 0)
190 				ia = in_ifaddr;
191 			if (ia == 0)
192 				return (EADDRNOTAVAIL);
193 		}
194 		ifaddr = (struct sockaddr_in *)&ia->ia_addr;
195 	}
196 	if (in_pcblookup(inp->inp_head,
197 	    sin->sin_addr,
198 	    sin->sin_port,
199 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
200 	    inp->inp_lport,
201 	    0))
202 		return (EADDRINUSE);
203 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
204 		if (inp->inp_lport == 0)
205 			(void)in_pcbbind(inp, (struct mbuf *)0);
206 		inp->inp_laddr = ifaddr->sin_addr;
207 	}
208 	inp->inp_faddr = sin->sin_addr;
209 	inp->inp_fport = sin->sin_port;
210 	return (0);
211 }
212 
213 in_pcbdisconnect(inp)
214 	struct inpcb *inp;
215 {
216 
217 	inp->inp_faddr.s_addr = INADDR_ANY;
218 	inp->inp_fport = 0;
219 	if (inp->inp_socket->so_state & SS_NOFDREF)
220 		in_pcbdetach(inp);
221 }
222 
223 in_pcbdetach(inp)
224 	struct inpcb *inp;
225 {
226 	struct socket *so = inp->inp_socket;
227 
228 	so->so_pcb = 0;
229 	sofree(so);
230 	if (inp->inp_options)
231 		(void)m_free(inp->inp_options);
232 	if (inp->inp_route.ro_rt)
233 		rtfree(inp->inp_route.ro_rt);
234 	remque(inp);
235 	(void) m_free(dtom(inp));
236 }
237 
238 in_setsockaddr(inp, nam)
239 	register struct inpcb *inp;
240 	struct mbuf *nam;
241 {
242 	register struct sockaddr_in *sin;
243 
244 	nam->m_len = sizeof (*sin);
245 	sin = mtod(nam, struct sockaddr_in *);
246 	bzero((caddr_t)sin, sizeof (*sin));
247 	sin->sin_family = AF_INET;
248 	sin->sin_len = sizeof(*sin);
249 	sin->sin_port = inp->inp_lport;
250 	sin->sin_addr = inp->inp_laddr;
251 }
252 
253 in_setpeeraddr(inp, nam)
254 	struct inpcb *inp;
255 	struct mbuf *nam;
256 {
257 	register struct sockaddr_in *sin;
258 
259 	nam->m_len = sizeof (*sin);
260 	sin = mtod(nam, struct sockaddr_in *);
261 	bzero((caddr_t)sin, sizeof (*sin));
262 	sin->sin_family = AF_INET;
263 	sin->sin_len = sizeof(*sin);
264 	sin->sin_port = inp->inp_fport;
265 	sin->sin_addr = inp->inp_faddr;
266 }
267 
268 /*
269  * Pass some notification to all connections of a protocol
270  * associated with address dst.  The local address and/or port numbers
271  * may be specified to limit the search.  The "usual action" will be
272  * taken, depending on the ctlinput cmd.  The caller must filter any
273  * cmds that are uninteresting (e.g., no error in the map).
274  * Call the protocol specific routine (if any) to report
275  * any errors for each matching socket.
276  *
277  * Must be called at splnet.
278  */
279 in_pcbnotify(head, dst, fport, laddr, lport, cmd, notify)
280 	struct inpcb *head;
281 	struct sockaddr *dst;
282 	u_short fport, lport;
283 	struct in_addr laddr;
284 	int cmd, (*notify)();
285 {
286 	register struct inpcb *inp, *oinp;
287 	struct in_addr faddr;
288 	int errno;
289 	int in_rtchange();
290 	extern u_char inetctlerrmap[];
291 
292 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET)
293 		return;
294 	faddr = ((struct sockaddr_in *)dst)->sin_addr;
295 	if (faddr.s_addr == INADDR_ANY)
296 		return;
297 
298 	/*
299 	 * Redirects go to all references to the destination,
300 	 * and use in_rtchange to invalidate the route cache.
301 	 * Dead host indications: notify all references to the destination.
302 	 * Otherwise, if we have knowledge of the local port and address,
303 	 * deliver only to that socket.
304 	 */
305 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
306 		fport = 0;
307 		lport = 0;
308 		laddr.s_addr = 0;
309 		if (cmd != PRC_HOSTDEAD)
310 			notify = in_rtchange;
311 	}
312 	errno = inetctlerrmap[cmd];
313 	for (inp = head->inp_next; inp != head;) {
314 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
315 		    inp->inp_socket == 0 ||
316 		    (lport && inp->inp_lport != lport) ||
317 		    (laddr.s_addr && inp->inp_laddr.s_addr != laddr.s_addr) ||
318 		    (fport && inp->inp_fport != fport)) {
319 			inp = inp->inp_next;
320 			continue;
321 		}
322 		oinp = inp;
323 		inp = inp->inp_next;
324 		if (notify)
325 			(*notify)(oinp, errno);
326 	}
327 }
328 
329 /*
330  * Check for alternatives when higher level complains
331  * about service problems.  For now, invalidate cached
332  * routing information.  If the route was created dynamically
333  * (by a redirect), time to try a default gateway again.
334  */
335 in_losing(inp)
336 	struct inpcb *inp;
337 {
338 	register struct rtentry *rt;
339 	struct rt_addrinfo info;
340 
341 	if ((rt = inp->inp_route.ro_rt)) {
342 		bzero((caddr_t)&info, sizeof(info));
343 		info.rti_info[RTAX_DST] =
344 			(struct sockaddr *)&inp->inp_route.ro_dst;
345 		info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
346 		info.rti_info[RTAX_NETMASK] = rt_mask(rt);
347 		rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
348 		if (rt->rt_flags & RTF_DYNAMIC)
349 			(void) rtrequest(RTM_DELETE, rt_key(rt),
350 				rt->rt_gateway, rt_mask(rt), rt->rt_flags,
351 				(struct rtentry **)0);
352 		inp->inp_route.ro_rt = 0;
353 		rtfree(rt);
354 		/*
355 		 * A new route can be allocated
356 		 * the next time output is attempted.
357 		 */
358 	}
359 }
360 
361 /*
362  * After a routing change, flush old routing
363  * and allocate a (hopefully) better one.
364  */
365 in_rtchange(inp)
366 	register struct inpcb *inp;
367 {
368 	if (inp->inp_route.ro_rt) {
369 		rtfree(inp->inp_route.ro_rt);
370 		inp->inp_route.ro_rt = 0;
371 		/*
372 		 * A new route can be allocated the next time
373 		 * output is attempted.
374 		 */
375 	}
376 }
377 
378 struct inpcb *
379 in_pcblookup(head, faddr, fport, laddr, lport, flags)
380 	struct inpcb *head;
381 	struct in_addr faddr, laddr;
382 	u_short fport, lport;
383 	int flags;
384 {
385 	register struct inpcb *inp, *match = 0;
386 	int matchwild = 3, wildcard;
387 
388 	for (inp = head->inp_next; inp != head; inp = inp->inp_next) {
389 		if (inp->inp_lport != lport)
390 			continue;
391 		wildcard = 0;
392 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
393 			if (laddr.s_addr == INADDR_ANY)
394 				wildcard++;
395 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
396 				continue;
397 		} else {
398 			if (laddr.s_addr != INADDR_ANY)
399 				wildcard++;
400 		}
401 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
402 			if (faddr.s_addr == INADDR_ANY)
403 				wildcard++;
404 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
405 			    inp->inp_fport != fport)
406 				continue;
407 		} else {
408 			if (faddr.s_addr != INADDR_ANY)
409 				wildcard++;
410 		}
411 		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
412 			continue;
413 		if (wildcard < matchwild) {
414 			match = inp;
415 			matchwild = wildcard;
416 			if (matchwild == 0)
417 				break;
418 		}
419 	}
420 	return (match);
421 }
422