xref: /freebsd/stand/libsa/netif.c (revision 7b54d275)
1 /*	$NetBSD: netif.c,v 1.10 1997/09/06 13:57:14 drochner Exp $	*/
2 
3 /*
4  * Copyright (c) 1993 Adam Glass
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Adam Glass.
18  * 4. The name of the Author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY Adam Glass ``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 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/param.h>
38 #include <sys/types.h>
39 #include <sys/cdefs.h>
40 #include <string.h>
41 
42 #include <netinet/in.h>
43 #include <netinet/in_systm.h>
44 
45 #include "stand.h"
46 #include "net.h"
47 #include "netif.h"
48 
49 typedef TAILQ_HEAD(socket_list, iodesc) socket_list_t;
50 
51 /*
52  * Open socket list. The current implementation and assumption is,
53  * we only remove entries from tail and we only add new entries to tail.
54  * This decision is to keep iodesc id management simple - we get list
55  * entries ordered by continiously growing io_id field.
56  * If we do have multiple sockets open and we do close socket not from tail,
57  * this entry will be marked unused. netif_open() will reuse unused entry, or
58  * netif_close() will free all unused tail entries.
59  */
60 static socket_list_t sockets = TAILQ_HEAD_INITIALIZER(sockets);
61 
62 #ifdef NETIF_DEBUG
63 int netif_debug = 0;
64 #endif
65 
66 /*
67  * netif_init:
68  *
69  * initialize the generic network interface layer
70  */
71 
72 void
73 netif_init(void)
74 {
75 	struct netif_driver *drv;
76 	int d, i;
77 
78 #ifdef NETIF_DEBUG
79 	if (netif_debug)
80 		printf("netif_init: called\n");
81 #endif
82 	for (d = 0; netif_drivers[d]; d++) {
83 		drv = netif_drivers[d];
84 		for (i = 0; i < drv->netif_nifs; i++)
85 			drv->netif_ifs[i].dif_used = 0;
86 	}
87 }
88 
89 int
90 netif_match(struct netif *nif, void *machdep_hint)
91 {
92 	struct netif_driver *drv = nif->nif_driver;
93 
94 #ifdef NETIF_DEBUG
95 	if (netif_debug)
96 		printf("%s%d: netif_match (%d)\n", drv->netif_bname,
97 		    nif->nif_unit, nif->nif_sel);
98 #endif
99 	return drv->netif_match(nif, machdep_hint);
100 }
101 
102 struct netif *
103 netif_select(void *machdep_hint)
104 {
105 	int d, u, s;
106 	struct netif_driver *drv;
107 	struct netif cur_if;
108 	static struct netif best_if;
109 	int best_val;
110 	int val;
111 
112 	best_val = 0;
113 	best_if.nif_driver = NULL;
114 
115 	for (d = 0; netif_drivers[d] != NULL; d++) {
116 		cur_if.nif_driver = netif_drivers[d];
117 		drv = cur_if.nif_driver;
118 
119 		for (u = 0; u < drv->netif_nifs; u++) {
120 			cur_if.nif_unit = u;
121 
122 #ifdef NETIF_DEBUG
123 			if (netif_debug)
124 				printf("\t%s%d:", drv->netif_bname,
125 				    cur_if.nif_unit);
126 #endif
127 
128 			for (s = 0; s < drv->netif_ifs[u].dif_nsel; s++) {
129 				cur_if.nif_sel = s;
130 
131 				if (drv->netif_ifs[u].dif_used & (1 << s)) {
132 #ifdef NETIF_DEBUG
133 					if (netif_debug)
134 						printf(" [%d used]", s);
135 #endif
136 					continue;
137 				}
138 
139 				val = netif_match(&cur_if, machdep_hint);
140 #ifdef NETIF_DEBUG
141 				if (netif_debug)
142 					printf(" [%d -> %d]", s, val);
143 #endif
144 				if (val > best_val) {
145 					best_val = val;
146 					best_if = cur_if;
147 				}
148 			}
149 #ifdef NETIF_DEBUG
150 			if (netif_debug)
151 				printf("\n");
152 #endif
153 		}
154 	}
155 
156 	if (best_if.nif_driver == NULL)
157 		return NULL;
158 
159 	best_if.nif_driver->
160 	    netif_ifs[best_if.nif_unit].dif_used |= (1 << best_if.nif_sel);
161 
162 #ifdef NETIF_DEBUG
163 	if (netif_debug)
164 		printf("netif_select: %s%d(%d) wins\n",
165 			best_if.nif_driver->netif_bname,
166 			best_if.nif_unit, best_if.nif_sel);
167 #endif
168 	return &best_if;
169 }
170 
171 int
172 netif_probe(struct netif *nif, void *machdep_hint)
173 {
174 	struct netif_driver *drv = nif->nif_driver;
175 
176 #ifdef NETIF_DEBUG
177 	if (netif_debug)
178 		printf("%s%d: netif_probe\n", drv->netif_bname, nif->nif_unit);
179 #endif
180 	return drv->netif_probe(nif, machdep_hint);
181 }
182 
183 void
184 netif_attach(struct netif *nif, struct iodesc *desc, void *machdep_hint)
185 {
186 	struct netif_driver *drv = nif->nif_driver;
187 
188 #ifdef NETIF_DEBUG
189 	if (netif_debug)
190 		printf("%s%d: netif_attach\n", drv->netif_bname, nif->nif_unit);
191 #endif
192 	desc->io_netif = nif;
193 #ifdef PARANOID
194 	if (drv->netif_init == NULL)
195 		panic("%s%d: no netif_init support", drv->netif_bname,
196 		    nif->nif_unit);
197 #endif
198 	drv->netif_init(desc, machdep_hint);
199 	bzero(drv->netif_ifs[nif->nif_unit].dif_stats,
200 	    sizeof(struct netif_stats));
201 }
202 
203 void
204 netif_detach(struct netif *nif)
205 {
206 	struct netif_driver *drv = nif->nif_driver;
207 
208 #ifdef NETIF_DEBUG
209 	if (netif_debug)
210 		printf("%s%d: netif_detach\n", drv->netif_bname, nif->nif_unit);
211 #endif
212 #ifdef PARANOID
213 	if (drv->netif_end == NULL)
214 		panic("%s%d: no netif_end support", drv->netif_bname,
215 		    nif->nif_unit);
216 #endif
217 	drv->netif_end(nif);
218 }
219 
220 ssize_t
221 netif_get(struct iodesc *desc, void **pkt, time_t timo)
222 {
223 #ifdef NETIF_DEBUG
224 	struct netif *nif = desc->io_netif;
225 #endif
226 	struct netif_driver *drv = desc->io_netif->nif_driver;
227 	ssize_t rv;
228 
229 #ifdef NETIF_DEBUG
230 	if (netif_debug)
231 		printf("%s%d: netif_get\n", drv->netif_bname, nif->nif_unit);
232 #endif
233 #ifdef PARANOID
234 	if (drv->netif_get == NULL)
235 		panic("%s%d: no netif_get support", drv->netif_bname,
236 		    nif->nif_unit);
237 #endif
238 	rv = drv->netif_get(desc, pkt, timo);
239 #ifdef NETIF_DEBUG
240 	if (netif_debug)
241 		printf("%s%d: netif_get returning %d\n", drv->netif_bname,
242 		    nif->nif_unit, (int)rv);
243 #endif
244 	return (rv);
245 }
246 
247 ssize_t
248 netif_put(struct iodesc *desc, void *pkt, size_t len)
249 {
250 #ifdef NETIF_DEBUG
251 	struct netif *nif = desc->io_netif;
252 #endif
253 	struct netif_driver *drv = desc->io_netif->nif_driver;
254 	ssize_t rv;
255 
256 #ifdef NETIF_DEBUG
257 	if (netif_debug)
258 		printf("%s%d: netif_put\n", drv->netif_bname, nif->nif_unit);
259 #endif
260 #ifdef PARANOID
261 	if (drv->netif_put == NULL)
262 		panic("%s%d: no netif_put support", drv->netif_bname,
263 		    nif->nif_unit);
264 #endif
265 	rv = drv->netif_put(desc, pkt, len);
266 #ifdef NETIF_DEBUG
267 	if (netif_debug)
268 		printf("%s%d: netif_put returning %d\n", drv->netif_bname,
269 		    nif->nif_unit, (int)rv);
270 #endif
271 	return (rv);
272 }
273 
274 /*
275  * socktodesc_impl:
276  *
277  * Walk socket list and return pointer to iodesc structure.
278  * if id is < 0, return first unused iodesc.
279  */
280 static struct iodesc *
281 socktodesc_impl(int socket)
282 {
283 	struct iodesc *s;
284 
285 	TAILQ_FOREACH(s, &sockets, io_link) {
286 		/* search by socket id */
287 		if (socket >= 0) {
288 			if (s->io_id == socket)
289 				break;
290 			continue;
291 		}
292 		/* search for first unused entry */
293 		if (s->io_netif == NULL)
294 			break;
295 	}
296 	return (s);
297 }
298 
299 struct iodesc *
300 socktodesc(int sock)
301 {
302 	struct iodesc *desc;
303 
304 	if (sock < 0)
305 		desc = NULL;
306 	else
307 		desc = socktodesc_impl(sock);
308 
309 	if (desc == NULL)
310 		errno = EBADF;
311 
312 	return (desc);
313 }
314 
315 int
316 netif_open(void *machdep_hint)
317 {
318 	struct iodesc *s;
319 	struct netif *nif;
320 
321 	/* find a free socket */
322 	s = socktodesc_impl(-1);
323 	if (s == NULL) {
324 		struct iodesc *last;
325 
326 		s = calloc(1, sizeof (*s));
327 		if (s == NULL)
328 			return (-1);
329 
330 		last = TAILQ_LAST(&sockets, socket_list);
331 		if (last != NULL)
332 			s->io_id = last->io_id + 1;
333 		TAILQ_INSERT_TAIL(&sockets, s, io_link);
334 	}
335 
336 	netif_init();
337 	nif = netif_select(machdep_hint);
338 	if (!nif)
339 		panic("netboot: no interfaces left untried");
340 	if (netif_probe(nif, machdep_hint)) {
341 		printf("netboot: couldn't probe %s%d\n",
342 		    nif->nif_driver->netif_bname, nif->nif_unit);
343 		errno = EINVAL;
344 		return (-1);
345 	}
346 	netif_attach(nif, s, machdep_hint);
347 
348 	return (s->io_id);
349 }
350 
351 int
352 netif_close(int sock)
353 {
354 	struct iodesc *s, *last;
355 	int err;
356 
357 	err = 0;
358 	s = socktodesc_impl(sock);
359 	if (s == NULL || sock < 0) {
360 		err = EBADF;
361 		return (-1);
362 	}
363 	netif_detach(s->io_netif);
364 	bzero(&s->destip, sizeof (s->destip));
365 	bzero(&s->myip, sizeof (s->myip));
366 	s->destport = 0;
367 	s->myport = 0;
368 	s->xid = 0;
369 	bzero(s->myea, sizeof (s->myea));
370 	s->io_netif = NULL;
371 
372 	/* free unused entries from tail. */
373 	TAILQ_FOREACH_REVERSE_SAFE(last, &sockets, socket_list, io_link, s) {
374 		if (last->io_netif != NULL)
375 			break;
376 		TAILQ_REMOVE(&sockets, last, io_link);
377 		free(last);
378 	}
379 
380 	if (err) {
381 		errno = err;
382 		return (-1);
383 	}
384 
385 	return (0);
386 }
387