xref: /original-bsd/sys/netinet/in_pcb.c (revision 75965087)
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	7.14 (Berkeley) 04/20/91
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 
19 #include "../net/if.h"
20 #include "../net/route.h"
21 
22 #include "in.h"
23 #include "in_systm.h"
24 #include "ip.h"
25 #include "in_pcb.h"
26 #include "in_var.h"
27 
28 struct	in_addr zeroin_addr;
29 
30 in_pcballoc(so, head)
31 	struct socket *so;
32 	struct inpcb *head;
33 {
34 	struct mbuf *m;
35 	register struct inpcb *inp;
36 
37 	m = m_getclr(M_DONTWAIT, MT_PCB);
38 	if (m == NULL)
39 		return (ENOBUFS);
40 	inp = mtod(m, struct inpcb *);
41 	inp->inp_head = head;
42 	inp->inp_socket = so;
43 	insque(inp, head);
44 	so->so_pcb = (caddr_t)inp;
45 	return (0);
46 }
47 
48 in_pcbbind(inp, nam)
49 	register struct inpcb *inp;
50 	struct mbuf *nam;
51 {
52 	register struct socket *so = inp->inp_socket;
53 	register struct inpcb *head = inp->inp_head;
54 	register struct sockaddr_in *sin;
55 	u_short lport = 0;
56 
57 	if (in_ifaddr == 0)
58 		return (EADDRNOTAVAIL);
59 	if (inp->inp_lport || inp->inp_laddr.s_addr != INADDR_ANY)
60 		return (EINVAL);
61 	if (nam == 0)
62 		goto noname;
63 	sin = mtod(nam, struct sockaddr_in *);
64 	if (nam->m_len != sizeof (*sin))
65 		return (EINVAL);
66 	if (sin->sin_addr.s_addr != INADDR_ANY) {
67 		int tport = sin->sin_port;
68 
69 		sin->sin_port = 0;		/* yech... */
70 		if (ifa_ifwithaddr((struct sockaddr *)sin) == 0)
71 			return (EADDRNOTAVAIL);
72 		sin->sin_port = tport;
73 	}
74 	lport = sin->sin_port;
75 	if (lport) {
76 		u_short aport = ntohs(lport);
77 		int wild = 0;
78 
79 		/* GROSS */
80 		if (aport < IPPORT_RESERVED && (so->so_state & SS_PRIV) == 0)
81 			return (EACCES);
82 		/* even GROSSER, but this is the Internet */
83 		if ((so->so_options & SO_REUSEADDR) == 0 &&
84 		    ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
85 		     (so->so_options & SO_ACCEPTCONN) == 0))
86 			wild = INPLOOKUP_WILDCARD;
87 		if (in_pcblookup(head,
88 		    zeroin_addr, 0, sin->sin_addr, lport, wild))
89 			return (EADDRINUSE);
90 	}
91 	inp->inp_laddr = sin->sin_addr;
92 noname:
93 	if (lport == 0)
94 		do {
95 			if (head->inp_lport++ < IPPORT_RESERVED ||
96 			    head->inp_lport > IPPORT_USERRESERVED)
97 				head->inp_lport = IPPORT_RESERVED;
98 			lport = htons(head->inp_lport);
99 		} while (in_pcblookup(head,
100 			    zeroin_addr, 0, inp->inp_laddr, lport, 0));
101 	inp->inp_lport = lport;
102 	return (0);
103 }
104 
105 /*
106  * Connect from a socket to a specified address.
107  * Both address and port must be specified in argument sin.
108  * If don't have a local address for this socket yet,
109  * then pick one.
110  */
111 in_pcbconnect(inp, nam)
112 	register struct inpcb *inp;
113 	struct mbuf *nam;
114 {
115 	struct in_ifaddr *ia;
116 	struct sockaddr_in *ifaddr;
117 	register struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
118 
119 	if (nam->m_len != sizeof (*sin))
120 		return (EINVAL);
121 	if (sin->sin_family != AF_INET)
122 		return (EAFNOSUPPORT);
123 	if (sin->sin_port == 0)
124 		return (EADDRNOTAVAIL);
125 	if (in_ifaddr) {
126 		/*
127 		 * If the destination address is INADDR_ANY,
128 		 * use the primary local address.
129 		 * If the supplied address is INADDR_BROADCAST,
130 		 * and the primary interface supports broadcast,
131 		 * choose the broadcast address for that interface.
132 		 */
133 #define	satosin(sa)	((struct sockaddr_in *)(sa))
134 		if (sin->sin_addr.s_addr == INADDR_ANY)
135 		    sin->sin_addr = IA_SIN(in_ifaddr)->sin_addr;
136 		else if (sin->sin_addr.s_addr == (u_long)INADDR_BROADCAST &&
137 		  (in_ifaddr->ia_ifp->if_flags & IFF_BROADCAST))
138 		    sin->sin_addr = satosin(&in_ifaddr->ia_broadaddr)->sin_addr;
139 	}
140 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
141 		register struct route *ro;
142 		struct ifnet *ifp;
143 
144 		ia = (struct in_ifaddr *)0;
145 		/*
146 		 * If route is known or can be allocated now,
147 		 * our src addr is taken from the i/f, else punt.
148 		 */
149 		ro = &inp->inp_route;
150 		if (ro->ro_rt &&
151 		    (satosin(&ro->ro_dst)->sin_addr.s_addr !=
152 			sin->sin_addr.s_addr ||
153 		    inp->inp_socket->so_options & SO_DONTROUTE)) {
154 			RTFREE(ro->ro_rt);
155 			ro->ro_rt = (struct rtentry *)0;
156 		}
157 		if ((inp->inp_socket->so_options & SO_DONTROUTE) == 0 && /*XXX*/
158 		    (ro->ro_rt == (struct rtentry *)0 ||
159 		    ro->ro_rt->rt_ifp == (struct ifnet *)0)) {
160 			/* No route yet, so try to acquire one */
161 			ro->ro_dst.sa_family = AF_INET;
162 			ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
163 			((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
164 				sin->sin_addr;
165 			rtalloc(ro);
166 		}
167 		/*
168 		 * If we found a route, use the address
169 		 * corresponding to the outgoing interface
170 		 * unless it is the loopback (in case a route
171 		 * to our address on another net goes to loopback).
172 		 */
173 		if (ro->ro_rt && (ifp = ro->ro_rt->rt_ifp) &&
174 		    (ifp->if_flags & IFF_LOOPBACK) == 0)
175 			for (ia = in_ifaddr; ia; ia = ia->ia_next)
176 				if (ia->ia_ifp == ifp)
177 					break;
178 		if (ia == 0) {
179 			int fport = sin->sin_port;
180 
181 			sin->sin_port = 0;
182 			ia = (struct in_ifaddr *)
183 			    ifa_ifwithdstaddr((struct sockaddr *)sin);
184 			sin->sin_port = fport;
185 			if (ia == 0)
186 				ia = in_iaonnetof(in_netof(sin->sin_addr));
187 			if (ia == 0)
188 				ia = in_ifaddr;
189 			if (ia == 0)
190 				return (EADDRNOTAVAIL);
191 		}
192 		ifaddr = (struct sockaddr_in *)&ia->ia_addr;
193 	}
194 	if (in_pcblookup(inp->inp_head,
195 	    sin->sin_addr,
196 	    sin->sin_port,
197 	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifaddr->sin_addr,
198 	    inp->inp_lport,
199 	    0))
200 		return (EADDRINUSE);
201 	if (inp->inp_laddr.s_addr == INADDR_ANY) {
202 		if (inp->inp_lport == 0)
203 			(void)in_pcbbind(inp, (struct mbuf *)0);
204 		inp->inp_laddr = ifaddr->sin_addr;
205 	}
206 	inp->inp_faddr = sin->sin_addr;
207 	inp->inp_fport = sin->sin_port;
208 	return (0);
209 }
210 
211 in_pcbdisconnect(inp)
212 	struct inpcb *inp;
213 {
214 
215 	inp->inp_faddr.s_addr = INADDR_ANY;
216 	inp->inp_fport = 0;
217 	if (inp->inp_socket->so_state & SS_NOFDREF)
218 		in_pcbdetach(inp);
219 }
220 
221 in_pcbdetach(inp)
222 	struct inpcb *inp;
223 {
224 	struct socket *so = inp->inp_socket;
225 
226 	so->so_pcb = 0;
227 	sofree(so);
228 	if (inp->inp_options)
229 		(void)m_free(inp->inp_options);
230 	if (inp->inp_route.ro_rt)
231 		rtfree(inp->inp_route.ro_rt);
232 	remque(inp);
233 	(void) m_free(dtom(inp));
234 }
235 
236 in_setsockaddr(inp, nam)
237 	register struct inpcb *inp;
238 	struct mbuf *nam;
239 {
240 	register struct sockaddr_in *sin;
241 
242 	nam->m_len = sizeof (*sin);
243 	sin = mtod(nam, struct sockaddr_in *);
244 	bzero((caddr_t)sin, sizeof (*sin));
245 	sin->sin_family = AF_INET;
246 	sin->sin_len = sizeof(*sin);
247 	sin->sin_port = inp->inp_lport;
248 	sin->sin_addr = inp->inp_laddr;
249 }
250 
251 in_setpeeraddr(inp, nam)
252 	struct inpcb *inp;
253 	struct mbuf *nam;
254 {
255 	register struct sockaddr_in *sin;
256 
257 	nam->m_len = sizeof (*sin);
258 	sin = mtod(nam, struct sockaddr_in *);
259 	bzero((caddr_t)sin, sizeof (*sin));
260 	sin->sin_family = AF_INET;
261 	sin->sin_len = sizeof(*sin);
262 	sin->sin_port = inp->inp_fport;
263 	sin->sin_addr = inp->inp_faddr;
264 }
265 
266 /*
267  * Pass some notification to all connections of a protocol
268  * associated with address dst.  The local address and/or port numbers
269  * may be specified to limit the search.  The "usual action" will be
270  * taken, depending on the ctlinput cmd.  The caller must filter any
271  * cmds that are uninteresting (e.g., no error in the map).
272  * Call the protocol specific routine (if any) to report
273  * any errors for each matching socket.
274  *
275  * Must be called at splnet.
276  */
277 in_pcbnotify(head, dst, fport, laddr, lport, cmd, notify)
278 	struct inpcb *head;
279 	struct sockaddr *dst;
280 	u_short fport, lport;
281 	struct in_addr laddr;
282 	int cmd, (*notify)();
283 {
284 	register struct inpcb *inp, *oinp;
285 	struct in_addr faddr;
286 	int errno;
287 	int in_rtchange();
288 	extern u_char inetctlerrmap[];
289 
290 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET)
291 		return;
292 	faddr = ((struct sockaddr_in *)dst)->sin_addr;
293 	if (faddr.s_addr == INADDR_ANY)
294 		return;
295 
296 	/*
297 	 * Redirects go to all references to the destination,
298 	 * and use in_rtchange to invalidate the route cache.
299 	 * Dead host indications: notify all references to the destination.
300 	 * Otherwise, if we have knowledge of the local port and address,
301 	 * deliver only to that socket.
302 	 */
303 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
304 		fport = 0;
305 		lport = 0;
306 		laddr.s_addr = 0;
307 		if (cmd != PRC_HOSTDEAD)
308 			notify = in_rtchange;
309 	}
310 	errno = inetctlerrmap[cmd];
311 	for (inp = head->inp_next; inp != head;) {
312 		if (inp->inp_faddr.s_addr != faddr.s_addr ||
313 		    inp->inp_socket == 0 ||
314 		    (lport && inp->inp_lport != lport) ||
315 		    (laddr.s_addr && inp->inp_laddr.s_addr != laddr.s_addr) ||
316 		    (fport && inp->inp_fport != fport)) {
317 			inp = inp->inp_next;
318 			continue;
319 		}
320 		oinp = inp;
321 		inp = inp->inp_next;
322 		if (notify)
323 			(*notify)(oinp, errno);
324 	}
325 }
326 
327 /*
328  * Check for alternatives when higher level complains
329  * about service problems.  For now, invalidate cached
330  * routing information.  If the route was created dynamically
331  * (by a redirect), time to try a default gateway again.
332  */
333 in_losing(inp)
334 	struct inpcb *inp;
335 {
336 	register struct rtentry *rt;
337 
338 	if ((rt = inp->inp_route.ro_rt)) {
339 		rt_missmsg(RTM_LOSING, &inp->inp_route.ro_dst,
340 			    rt->rt_gateway, (struct sockaddr *)rt_mask(rt),
341 			    (struct sockaddr *)0, rt->rt_flags, 0);
342 		if (rt->rt_flags & RTF_DYNAMIC)
343 			(void) rtrequest(RTM_DELETE, rt_key(rt),
344 				rt->rt_gateway, rt_mask(rt), rt->rt_flags,
345 				(struct rtentry **)0);
346 		inp->inp_route.ro_rt = 0;
347 		rtfree(rt);
348 		/*
349 		 * A new route can be allocated
350 		 * the next time output is attempted.
351 		 */
352 	}
353 }
354 
355 /*
356  * After a routing change, flush old routing
357  * and allocate a (hopefully) better one.
358  */
359 in_rtchange(inp)
360 	register struct inpcb *inp;
361 {
362 	if (inp->inp_route.ro_rt) {
363 		rtfree(inp->inp_route.ro_rt);
364 		inp->inp_route.ro_rt = 0;
365 		/*
366 		 * A new route can be allocated the next time
367 		 * output is attempted.
368 		 */
369 	}
370 }
371 
372 struct inpcb *
373 in_pcblookup(head, faddr, fport, laddr, lport, flags)
374 	struct inpcb *head;
375 	struct in_addr faddr, laddr;
376 	u_short fport, lport;
377 	int flags;
378 {
379 	register struct inpcb *inp, *match = 0;
380 	int matchwild = 3, wildcard;
381 
382 	for (inp = head->inp_next; inp != head; inp = inp->inp_next) {
383 		if (inp->inp_lport != lport)
384 			continue;
385 		wildcard = 0;
386 		if (inp->inp_laddr.s_addr != INADDR_ANY) {
387 			if (laddr.s_addr == INADDR_ANY)
388 				wildcard++;
389 			else if (inp->inp_laddr.s_addr != laddr.s_addr)
390 				continue;
391 		} else {
392 			if (laddr.s_addr != INADDR_ANY)
393 				wildcard++;
394 		}
395 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
396 			if (faddr.s_addr == INADDR_ANY)
397 				wildcard++;
398 			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
399 			    inp->inp_fport != fport)
400 				continue;
401 		} else {
402 			if (faddr.s_addr != INADDR_ANY)
403 				wildcard++;
404 		}
405 		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
406 			continue;
407 		if (wildcard < matchwild) {
408 			match = inp;
409 			matchwild = wildcard;
410 			if (matchwild == 0)
411 				break;
412 		}
413 	}
414 	return (match);
415 }
416