xref: /original-bsd/sys/netinet/in_pcb.c (revision 2301fdfb)
1 /*
2  * Copyright (c) 1982, 1986 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  *
17  *	@(#)in_pcb.c	7.8 (Berkeley) 10/12/88
18  */
19 
20 #include "param.h"
21 #include "systm.h"
22 #include "dir.h"
23 #include "user.h"
24 #include "malloc.h"
25 #include "mbuf.h"
26 #include "socket.h"
27 #include "socketvar.h"
28 #include "ioctl.h"
29 #include "in.h"
30 #include "in_systm.h"
31 #include "../net/if.h"
32 #include "../net/route.h"
33 #include "in_pcb.h"
34 #include "in_var.h"
35 #include "protosw.h"
36 
37 struct	in_addr zeroin_addr;
38 
39 in_pcballoc(so, head)
40 	struct socket *so;
41 	struct inpcb *head;
42 {
43 	struct mbuf *m;
44 	register struct inpcb *inp;
45 
46 	m = m_getclr(M_DONTWAIT, MT_PCB);
47 	if (m == NULL)
48 		return (ENOBUFS);
49 	inp = mtod(m, struct inpcb *);
50 	inp->inp_head = head;
51 	inp->inp_socket = so;
52 	insque(inp, head);
53 	so->so_pcb = (caddr_t)inp;
54 	return (0);
55 }
56 
57 in_pcbbind(inp, nam)
58 	register struct inpcb *inp;
59 	struct mbuf *nam;
60 {
61 	register struct socket *so = inp->inp_socket;
62 	register struct inpcb *head = inp->inp_head;
63 	register struct sockaddr_in *sin;
64 	u_short lport = 0;
65 
66 	if (in_ifaddr == 0)
67 		return (EADDRNOTAVAIL);
68 	if (inp->inp_lport || inp->inp_laddr.s_addr != INADDR_ANY)
69 		return (EINVAL);
70 	if (nam == 0)
71 		goto noname;
72 	sin = mtod(nam, struct sockaddr_in *);
73 	if (nam->m_len != sizeof (*sin))
74 		return (EINVAL);
75 	if (sin->sin_addr.s_addr != INADDR_ANY) {
76 		int tport = sin->sin_port;
77 
78 		sin->sin_port = 0;		/* yech... */
79 		if (ifa_ifwithaddr((struct sockaddr *)sin) == 0)
80 			return (EADDRNOTAVAIL);
81 		sin->sin_port = tport;
82 	}
83 	lport = sin->sin_port;
84 	if (lport) {
85 		u_short aport = ntohs(lport);
86 		int wild = 0;
87 
88 		/* GROSS */
89 		if (aport < IPPORT_RESERVED && u.u_uid != 0)
90 			return (EACCES);
91 		/* even GROSSER, but this is the Internet */
92 		if ((so->so_options & SO_REUSEADDR) == 0 &&
93 		    ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
94 		     (so->so_options & SO_ACCEPTCONN) == 0))
95 			wild = INPLOOKUP_WILDCARD;
96 		if (in_pcblookup(head,
97 		    zeroin_addr, 0, sin->sin_addr, lport, wild))
98 			return (EADDRINUSE);
99 	}
100 	inp->inp_laddr = sin->sin_addr;
101 noname:
102 	if (lport == 0)
103 		do {
104 			if (head->inp_lport++ < IPPORT_RESERVED ||
105 			    head->inp_lport > IPPORT_USERRESERVED)
106 				head->inp_lport = IPPORT_RESERVED;
107 			lport = htons(head->inp_lport);
108 		} while (in_pcblookup(head,
109 			    zeroin_addr, 0, inp->inp_laddr, lport, 0));
110 	inp->inp_lport = lport;
111 	return (0);
112 }
113 
114 /*
115  * Connect from a socket to a specified address.
116  * Both address and port must be specified in argument sin.
117  * If don't have a local address for this socket yet,
118  * then pick one.
119  */
120 in_pcbconnect(inp, nam)
121 	register struct inpcb *inp;
122 	struct mbuf *nam;
123 {
124 	struct in_ifaddr *ia;
125 	struct sockaddr_in *ifaddr;
126 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
127 
128 	if (nam->m_len != sizeof (*sin))
129 		return (EINVAL);
130 	if (sin->sin_family != AF_INET)
131 		return (EAFNOSUPPORT);
132 	if (sin->sin_port == 0)
133 		return (EADDRNOTAVAIL);
134 	if (in_ifaddr) {
135 		/*
136 		 * If the destination address is INADDR_ANY,
137 		 * use the primary local address.
138 		 * If the supplied address is INADDR_BROADCAST,
139 		 * and the primary interface supports broadcast,
140 		 * choose the broadcast address for that interface.
141 		 */
142 #define	satosin(sa)	((struct sockaddr_in *)(sa))
143 		if (sin->sin_addr.s_addr == INADDR_ANY)
144 		    sin->sin_addr = IA_SIN(in_ifaddr)->sin_addr;
145 		else if (sin->sin_addr.s_addr == (u_long)INADDR_BROADCAST &&
146 		  (in_ifaddr->ia_ifp->if_flags & IFF_BROADCAST))
147 		    sin->sin_addr = satosin(&in_ifaddr->ia_broadaddr)->sin_addr;
148 	}
149 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
150 		register struct route *ro;
151 		struct ifnet *ifp;
152 
153 		ia = (struct in_ifaddr *)0;
154 		/*
155 		 * If route is known or can be allocated now,
156 		 * our src addr is taken from the i/f, else punt.
157 		 */
158 		ro = &inp->inp_route;
159 		if (ro->ro_rt &&
160 		    (satosin(&ro->ro_dst)->sin_addr.s_addr !=
161 			sin->sin_addr.s_addr ||
162 		    inp->inp_socket->so_options & SO_DONTROUTE)) {
163 			RTFREE(ro->ro_rt);
164 			ro->ro_rt = (struct rtentry *)0;
165 		}
166 		if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0 && /*XXX*/
167 		    (ro->ro_rt == (struct rtentry *)0 ||
168 		    ro->ro_rt->rt_ifp == (struct ifnet *)0)) {
169 			/* No route yet, so try to acquire one */
170 			ro->ro_dst.sa_family = AF_INET;
171 			((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
172 				sin->sin_addr;
173 			rtalloc(ro);
174 		}
175 		/*
176 		 * If we found a route, use the address
177 		 * corresponding to the outgoing interface
178 		 * unless it is the loopback (in case a route
179 		 * to our address on another net goes to loopback).
180 		 */
181 		if (ro->ro_rt && (ifp = ro->ro_rt->rt_ifp) &&
182 		    (ifp->if_flags & IFF_LOOPBACK) == 0)
183 			for (ia = in_ifaddr; ia; ia = ia->ia_next)
184 				if (ia->ia_ifp == ifp)
185 					break;
186 		if (ia == 0) {
187 			int fport = sin->sin_port;
188 
189 			sin->sin_port = 0;
190 			ia = (struct in_ifaddr *)
191 			    ifa_ifwithdstaddr((struct sockaddr *)sin);
192 			sin->sin_port = fport;
193 			if (ia == 0)
194 				ia = in_iaonnetof(in_netof(sin->sin_addr));
195 			if (ia == 0)
196 				ia = in_ifaddr;
197 			if (ia == 0)
198 				return (EADDRNOTAVAIL);
199 		}
200 		ifaddr = (struct sockaddr_in *)&ia->ia_addr;
201 	}
202 	if (in_pcblookup(inp->inp_head,
203 	    sin->sin_addr,
204 	    sin->sin_port,
205 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
206 	    inp->inp_lport,
207 	    0))
208 		return (EADDRINUSE);
209 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
210 		if (inp->inp_lport == 0)
211 			(void)in_pcbbind(inp, (struct mbuf *)0);
212 		inp->inp_laddr = ifaddr->sin_addr;
213 	}
214 	inp->inp_faddr = sin->sin_addr;
215 	inp->inp_fport = sin->sin_port;
216 	return (0);
217 }
218 
219 in_pcbdisconnect(inp)
220 	struct inpcb *inp;
221 {
222 
223 	inp->inp_faddr.s_addr = INADDR_ANY;
224 	inp->inp_fport = 0;
225 	if (inp->inp_socket->so_state & SS_NOFDREF)
226 		in_pcbdetach(inp);
227 }
228 
229 in_pcbdetach(inp)
230 	struct inpcb *inp;
231 {
232 	struct socket *so = inp->inp_socket;
233 
234 	so->so_pcb = 0;
235 	sofree(so);
236 	if (inp->inp_options)
237 		(void)m_free(inp->inp_options);
238 	if (inp->inp_route.ro_rt)
239 		rtfree(inp->inp_route.ro_rt);
240 	remque(inp);
241 	(void) m_free(dtom(inp));
242 }
243 
244 in_setsockaddr(inp, nam)
245 	register struct inpcb *inp;
246 	struct mbuf *nam;
247 {
248 	register struct sockaddr_in *sin;
249 
250 	nam->m_len = sizeof (*sin);
251 	sin = mtod(nam, struct sockaddr_in *);
252 	bzero((caddr_t)sin, sizeof (*sin));
253 	sin->sin_family = AF_INET;
254 	sin->sin_port = inp->inp_lport;
255 	sin->sin_addr = inp->inp_laddr;
256 }
257 
258 in_setpeeraddr(inp, nam)
259 	struct inpcb *inp;
260 	struct mbuf *nam;
261 {
262 	register struct sockaddr_in *sin;
263 
264 	nam->m_len = sizeof (*sin);
265 	sin = mtod(nam, struct sockaddr_in *);
266 	bzero((caddr_t)sin, sizeof (*sin));
267 	sin->sin_family = AF_INET;
268 	sin->sin_port = inp->inp_fport;
269 	sin->sin_addr = inp->inp_faddr;
270 }
271 
272 /*
273  * Pass some notification to all connections of a protocol
274  * associated with address dst.  Call the protocol specific
275  * routine (if any) to handle each connection.
276  */
277 in_pcbnotify(head, dst, errno, notify)
278 	struct inpcb *head;
279 	register struct in_addr *dst;
280 	int errno, (*notify)();
281 {
282 	register struct inpcb *inp, *oinp;
283 	int s = splimp();
284 
285 	for (inp = head->inp_next; inp != head;) {
286 		if (inp->inp_faddr.s_addr != dst->s_addr ||
287 		    inp->inp_socket == 0) {
288 			inp = inp->inp_next;
289 			continue;
290 		}
291 		if (errno)
292 			inp->inp_socket->so_error = errno;
293 		oinp = inp;
294 		inp = inp->inp_next;
295 		if (notify)
296 			(*notify)(oinp);
297 	}
298 	splx(s);
299 }
300 
301 /*
302  * Check for alternatives when higher level complains
303  * about service problems.  For now, invalidate cached
304  * routing information.  If the route was created dynamically
305  * (by a redirect), time to try a default gateway again.
306  */
307 in_losing(inp)
308 	struct inpcb *inp;
309 {
310 	register struct rtentry *rt;
311 
312 	if ((rt = inp->inp_route.ro_rt)) {
313 		if (rt->rt_flags & RTF_DYNAMIC)
314 			(void) rtrequest((int)SIOCDELRT, rt);
315 		rtfree(rt);
316 		inp->inp_route.ro_rt = 0;
317 		/*
318 		 * A new route can be allocated
319 		 * the next time output is attempted.
320 		 */
321 	}
322 }
323 
324 /*
325  * After a routing change, flush old routing
326  * and allocate a (hopefully) better one.
327  */
328 in_rtchange(inp)
329 	register struct inpcb *inp;
330 {
331 	if (inp->inp_route.ro_rt) {
332 		rtfree(inp->inp_route.ro_rt);
333 		inp->inp_route.ro_rt = 0;
334 		/*
335 		 * A new route can be allocated the next time
336 		 * output is attempted.
337 		 */
338 	}
339 }
340 
341 struct inpcb *
342 in_pcblookup(head, faddr, fport, laddr, lport, flags)
343 	struct inpcb *head;
344 	struct in_addr faddr, laddr;
345 	u_short fport, lport;
346 	int flags;
347 {
348 	register struct inpcb *inp, *match = 0;
349 	int matchwild = 3, wildcard;
350 
351 	for (inp = head->inp_next; inp != head; inp = inp->inp_next) {
352 		if (inp->inp_lport != lport)
353 			continue;
354 		wildcard = 0;
355 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
356 			if (laddr.s_addr == INADDR_ANY)
357 				wildcard++;
358 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
359 				continue;
360 		} else {
361 			if (laddr.s_addr != INADDR_ANY)
362 				wildcard++;
363 		}
364 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
365 			if (faddr.s_addr == INADDR_ANY)
366 				wildcard++;
367 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
368 			    inp->inp_fport != fport)
369 				continue;
370 		} else {
371 			if (faddr.s_addr != INADDR_ANY)
372 				wildcard++;
373 		}
374 		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
375 			continue;
376 		if (wildcard < matchwild) {
377 			match = inp;
378 			matchwild = wildcard;
379 			if (matchwild == 0)
380 				break;
381 		}
382 	}
383 	return (match);
384 }
385