xref: /original-bsd/sys/netinet/in_pcb.c (revision e59fb703)
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	7.15 (Berkeley) 10/02/91
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 			for (ia = in_ifaddr; ia; ia = ia->ia_next)
177 				if (ia->ia_ifp == ifp)
178 					break;
179 		if (ia == 0) {
180 			int fport = sin->sin_port;
181 
182 			sin->sin_port = 0;
183 			ia = (struct in_ifaddr *)
184 			    ifa_ifwithdstaddr((struct sockaddr *)sin);
185 			sin->sin_port = fport;
186 			if (ia == 0)
187 				ia = in_iaonnetof(in_netof(sin->sin_addr));
188 			if (ia == 0)
189 				ia = in_ifaddr;
190 			if (ia == 0)
191 				return (EADDRNOTAVAIL);
192 		}
193 		ifaddr = (struct sockaddr_in *)&ia->ia_addr;
194 	}
195 	if (in_pcblookup(inp->inp_head,
196 	    sin->sin_addr,
197 	    sin->sin_port,
198 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
199 	    inp->inp_lport,
200 	    0))
201 		return (EADDRINUSE);
202 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
203 		if (inp->inp_lport == 0)
204 			(void)in_pcbbind(inp, (struct mbuf *)0);
205 		inp->inp_laddr = ifaddr->sin_addr;
206 	}
207 	inp->inp_faddr = sin->sin_addr;
208 	inp->inp_fport = sin->sin_port;
209 	return (0);
210 }
211 
212 in_pcbdisconnect(inp)
213 	struct inpcb *inp;
214 {
215 
216 	inp->inp_faddr.s_addr = INADDR_ANY;
217 	inp->inp_fport = 0;
218 	if (inp->inp_socket->so_state & SS_NOFDREF)
219 		in_pcbdetach(inp);
220 }
221 
222 in_pcbdetach(inp)
223 	struct inpcb *inp;
224 {
225 	struct socket *so = inp->inp_socket;
226 
227 	so->so_pcb = 0;
228 	sofree(so);
229 	if (inp->inp_options)
230 		(void)m_free(inp->inp_options);
231 	if (inp->inp_route.ro_rt)
232 		rtfree(inp->inp_route.ro_rt);
233 	remque(inp);
234 	(void) m_free(dtom(inp));
235 }
236 
237 in_setsockaddr(inp, nam)
238 	register struct inpcb *inp;
239 	struct mbuf *nam;
240 {
241 	register struct sockaddr_in *sin;
242 
243 	nam->m_len = sizeof (*sin);
244 	sin = mtod(nam, struct sockaddr_in *);
245 	bzero((caddr_t)sin, sizeof (*sin));
246 	sin->sin_family = AF_INET;
247 	sin->sin_len = sizeof(*sin);
248 	sin->sin_port = inp->inp_lport;
249 	sin->sin_addr = inp->inp_laddr;
250 }
251 
252 in_setpeeraddr(inp, nam)
253 	struct inpcb *inp;
254 	struct mbuf *nam;
255 {
256 	register struct sockaddr_in *sin;
257 
258 	nam->m_len = sizeof (*sin);
259 	sin = mtod(nam, struct sockaddr_in *);
260 	bzero((caddr_t)sin, sizeof (*sin));
261 	sin->sin_family = AF_INET;
262 	sin->sin_len = sizeof(*sin);
263 	sin->sin_port = inp->inp_fport;
264 	sin->sin_addr = inp->inp_faddr;
265 }
266 
267 /*
268  * Pass some notification to all connections of a protocol
269  * associated with address dst.  The local address and/or port numbers
270  * may be specified to limit the search.  The "usual action" will be
271  * taken, depending on the ctlinput cmd.  The caller must filter any
272  * cmds that are uninteresting (e.g., no error in the map).
273  * Call the protocol specific routine (if any) to report
274  * any errors for each matching socket.
275  *
276  * Must be called at splnet.
277  */
278 in_pcbnotify(head, dst, fport, laddr, lport, cmd, notify)
279 	struct inpcb *head;
280 	struct sockaddr *dst;
281 	u_short fport, lport;
282 	struct in_addr laddr;
283 	int cmd, (*notify)();
284 {
285 	register struct inpcb *inp, *oinp;
286 	struct in_addr faddr;
287 	int errno;
288 	int in_rtchange();
289 	extern u_char inetctlerrmap[];
290 
291 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET)
292 		return;
293 	faddr = ((struct sockaddr_in *)dst)->sin_addr;
294 	if (faddr.s_addr == INADDR_ANY)
295 		return;
296 
297 	/*
298 	 * Redirects go to all references to the destination,
299 	 * and use in_rtchange to invalidate the route cache.
300 	 * Dead host indications: notify all references to the destination.
301 	 * Otherwise, if we have knowledge of the local port and address,
302 	 * deliver only to that socket.
303 	 */
304 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
305 		fport = 0;
306 		lport = 0;
307 		laddr.s_addr = 0;
308 		if (cmd != PRC_HOSTDEAD)
309 			notify = in_rtchange;
310 	}
311 	errno = inetctlerrmap[cmd];
312 	for (inp = head->inp_next; inp != head;) {
313 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
314 		    inp->inp_socket == 0 ||
315 		    (lport && inp->inp_lport != lport) ||
316 		    (laddr.s_addr && inp->inp_laddr.s_addr != laddr.s_addr) ||
317 		    (fport && inp->inp_fport != fport)) {
318 			inp = inp->inp_next;
319 			continue;
320 		}
321 		oinp = inp;
322 		inp = inp->inp_next;
323 		if (notify)
324 			(*notify)(oinp, errno);
325 	}
326 }
327 
328 /*
329  * Check for alternatives when higher level complains
330  * about service problems.  For now, invalidate cached
331  * routing information.  If the route was created dynamically
332  * (by a redirect), time to try a default gateway again.
333  */
334 in_losing(inp)
335 	struct inpcb *inp;
336 {
337 	register struct rtentry *rt;
338 
339 	if ((rt = inp->inp_route.ro_rt)) {
340 		rt_missmsg(RTM_LOSING, &inp->inp_route.ro_dst,
341 			    rt->rt_gateway, (struct sockaddr *)rt_mask(rt),
342 			    (struct sockaddr *)0, rt->rt_flags, 0);
343 		if (rt->rt_flags & RTF_DYNAMIC)
344 			(void) rtrequest(RTM_DELETE, rt_key(rt),
345 				rt->rt_gateway, rt_mask(rt), rt->rt_flags,
346 				(struct rtentry **)0);
347 		inp->inp_route.ro_rt = 0;
348 		rtfree(rt);
349 		/*
350 		 * A new route can be allocated
351 		 * the next time output is attempted.
352 		 */
353 	}
354 }
355 
356 /*
357  * After a routing change, flush old routing
358  * and allocate a (hopefully) better one.
359  */
360 in_rtchange(inp)
361 	register struct inpcb *inp;
362 {
363 	if (inp->inp_route.ro_rt) {
364 		rtfree(inp->inp_route.ro_rt);
365 		inp->inp_route.ro_rt = 0;
366 		/*
367 		 * A new route can be allocated the next time
368 		 * output is attempted.
369 		 */
370 	}
371 }
372 
373 struct inpcb *
374 in_pcblookup(head, faddr, fport, laddr, lport, flags)
375 	struct inpcb *head;
376 	struct in_addr faddr, laddr;
377 	u_short fport, lport;
378 	int flags;
379 {
380 	register struct inpcb *inp, *match = 0;
381 	int matchwild = 3, wildcard;
382 
383 	for (inp = head->inp_next; inp != head; inp = inp->inp_next) {
384 		if (inp->inp_lport != lport)
385 			continue;
386 		wildcard = 0;
387 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
388 			if (laddr.s_addr == INADDR_ANY)
389 				wildcard++;
390 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
391 				continue;
392 		} else {
393 			if (laddr.s_addr != INADDR_ANY)
394 				wildcard++;
395 		}
396 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
397 			if (faddr.s_addr == INADDR_ANY)
398 				wildcard++;
399 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
400 			    inp->inp_fport != fport)
401 				continue;
402 		} else {
403 			if (faddr.s_addr != INADDR_ANY)
404 				wildcard++;
405 		}
406 		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
407 			continue;
408 		if (wildcard < matchwild) {
409 			match = inp;
410 			matchwild = wildcard;
411 			if (matchwild == 0)
412 				break;
413 		}
414 	}
415 	return (match);
416 }
417