xref: /freebsd/stand/libsa/netif.c (revision 1d386b48)
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 #include <sys/param.h>
36 #include <sys/types.h>
37 #include <sys/cdefs.h>
38 #include <string.h>
39 
40 #include <netinet/in.h>
41 #include <netinet/in_systm.h>
42 
43 #include "stand.h"
44 #include "net.h"
45 #include "netif.h"
46 
47 typedef TAILQ_HEAD(socket_list, iodesc) socket_list_t;
48 
49 /*
50  * Open socket list. The current implementation and assumption is,
51  * we only remove entries from tail and we only add new entries to tail.
52  * This decision is to keep iodesc id management simple - we get list
53  * entries ordered by continiously growing io_id field.
54  * If we do have multiple sockets open and we do close socket not from tail,
55  * this entry will be marked unused. netif_open() will reuse unused entry, or
56  * netif_close() will free all unused tail entries.
57  */
58 static socket_list_t sockets = TAILQ_HEAD_INITIALIZER(sockets);
59 
60 #ifdef NETIF_DEBUG
61 int netif_debug = 0;
62 #endif
63 
64 /*
65  * netif_init:
66  *
67  * initialize the generic network interface layer
68  */
69 
70 void
71 netif_init(void)
72 {
73 	struct netif_driver *drv;
74 	int d, i;
75 
76 #ifdef NETIF_DEBUG
77 	if (netif_debug)
78 		printf("netif_init: called\n");
79 #endif
80 	for (d = 0; netif_drivers[d]; d++) {
81 		drv = netif_drivers[d];
82 		for (i = 0; i < drv->netif_nifs; i++)
83 			drv->netif_ifs[i].dif_used = 0;
84 	}
85 }
86 
87 int
88 netif_match(struct netif *nif, void *machdep_hint)
89 {
90 	struct netif_driver *drv = nif->nif_driver;
91 
92 #ifdef NETIF_DEBUG
93 	if (netif_debug)
94 		printf("%s%d: netif_match (%d)\n", drv->netif_bname,
95 		    nif->nif_unit, nif->nif_sel);
96 #endif
97 	return drv->netif_match(nif, machdep_hint);
98 }
99 
100 struct netif *
101 netif_select(void *machdep_hint)
102 {
103 	int d, u, s;
104 	struct netif_driver *drv;
105 	struct netif cur_if;
106 	static struct netif best_if;
107 	int best_val;
108 	int val;
109 
110 	best_val = 0;
111 	best_if.nif_driver = NULL;
112 
113 	for (d = 0; netif_drivers[d] != NULL; d++) {
114 		cur_if.nif_driver = netif_drivers[d];
115 		drv = cur_if.nif_driver;
116 
117 		for (u = 0; u < drv->netif_nifs; u++) {
118 			cur_if.nif_unit = u;
119 
120 #ifdef NETIF_DEBUG
121 			if (netif_debug)
122 				printf("\t%s%d:", drv->netif_bname,
123 				    cur_if.nif_unit);
124 #endif
125 
126 			for (s = 0; s < drv->netif_ifs[u].dif_nsel; s++) {
127 				cur_if.nif_sel = s;
128 
129 				if (drv->netif_ifs[u].dif_used & (1 << s)) {
130 #ifdef NETIF_DEBUG
131 					if (netif_debug)
132 						printf(" [%d used]", s);
133 #endif
134 					continue;
135 				}
136 
137 				val = netif_match(&cur_if, machdep_hint);
138 #ifdef NETIF_DEBUG
139 				if (netif_debug)
140 					printf(" [%d -> %d]", s, val);
141 #endif
142 				if (val > best_val) {
143 					best_val = val;
144 					best_if = cur_if;
145 				}
146 			}
147 #ifdef NETIF_DEBUG
148 			if (netif_debug)
149 				printf("\n");
150 #endif
151 		}
152 	}
153 
154 	if (best_if.nif_driver == NULL)
155 		return NULL;
156 
157 	best_if.nif_driver->
158 	    netif_ifs[best_if.nif_unit].dif_used |= (1 << best_if.nif_sel);
159 
160 #ifdef NETIF_DEBUG
161 	if (netif_debug)
162 		printf("netif_select: %s%d(%d) wins\n",
163 			best_if.nif_driver->netif_bname,
164 			best_if.nif_unit, best_if.nif_sel);
165 #endif
166 	return &best_if;
167 }
168 
169 int
170 netif_probe(struct netif *nif, void *machdep_hint)
171 {
172 	struct netif_driver *drv = nif->nif_driver;
173 
174 #ifdef NETIF_DEBUG
175 	if (netif_debug)
176 		printf("%s%d: netif_probe\n", drv->netif_bname, nif->nif_unit);
177 #endif
178 	return drv->netif_probe(nif, machdep_hint);
179 }
180 
181 void
182 netif_attach(struct netif *nif, struct iodesc *desc, void *machdep_hint)
183 {
184 	struct netif_driver *drv = nif->nif_driver;
185 
186 #ifdef NETIF_DEBUG
187 	if (netif_debug)
188 		printf("%s%d: netif_attach\n", drv->netif_bname, nif->nif_unit);
189 #endif
190 	desc->io_netif = nif;
191 #ifdef PARANOID
192 	if (drv->netif_init == NULL)
193 		panic("%s%d: no netif_init support", drv->netif_bname,
194 		    nif->nif_unit);
195 #endif
196 	drv->netif_init(desc, machdep_hint);
197 	bzero(drv->netif_ifs[nif->nif_unit].dif_stats,
198 	    sizeof(struct netif_stats));
199 }
200 
201 void
202 netif_detach(struct netif *nif)
203 {
204 	struct netif_driver *drv = nif->nif_driver;
205 
206 #ifdef NETIF_DEBUG
207 	if (netif_debug)
208 		printf("%s%d: netif_detach\n", drv->netif_bname, nif->nif_unit);
209 #endif
210 #ifdef PARANOID
211 	if (drv->netif_end == NULL)
212 		panic("%s%d: no netif_end support", drv->netif_bname,
213 		    nif->nif_unit);
214 #endif
215 	drv->netif_end(nif);
216 }
217 
218 ssize_t
219 netif_get(struct iodesc *desc, void **pkt, time_t timo)
220 {
221 #ifdef NETIF_DEBUG
222 	struct netif *nif = desc->io_netif;
223 #endif
224 	struct netif_driver *drv = desc->io_netif->nif_driver;
225 	ssize_t rv;
226 
227 #ifdef NETIF_DEBUG
228 	if (netif_debug)
229 		printf("%s%d: netif_get\n", drv->netif_bname, nif->nif_unit);
230 #endif
231 #ifdef PARANOID
232 	if (drv->netif_get == NULL)
233 		panic("%s%d: no netif_get support", drv->netif_bname,
234 		    nif->nif_unit);
235 #endif
236 	rv = drv->netif_get(desc, pkt, timo);
237 #ifdef NETIF_DEBUG
238 	if (netif_debug)
239 		printf("%s%d: netif_get returning %d\n", drv->netif_bname,
240 		    nif->nif_unit, (int)rv);
241 #endif
242 	return (rv);
243 }
244 
245 ssize_t
246 netif_put(struct iodesc *desc, void *pkt, size_t len)
247 {
248 #ifdef NETIF_DEBUG
249 	struct netif *nif = desc->io_netif;
250 #endif
251 	struct netif_driver *drv = desc->io_netif->nif_driver;
252 	ssize_t rv;
253 
254 #ifdef NETIF_DEBUG
255 	if (netif_debug)
256 		printf("%s%d: netif_put\n", drv->netif_bname, nif->nif_unit);
257 #endif
258 #ifdef PARANOID
259 	if (drv->netif_put == NULL)
260 		panic("%s%d: no netif_put support", drv->netif_bname,
261 		    nif->nif_unit);
262 #endif
263 	rv = drv->netif_put(desc, pkt, len);
264 #ifdef NETIF_DEBUG
265 	if (netif_debug)
266 		printf("%s%d: netif_put returning %d\n", drv->netif_bname,
267 		    nif->nif_unit, (int)rv);
268 #endif
269 	return (rv);
270 }
271 
272 /*
273  * socktodesc_impl:
274  *
275  * Walk socket list and return pointer to iodesc structure.
276  * if id is < 0, return first unused iodesc.
277  */
278 static struct iodesc *
279 socktodesc_impl(int socket)
280 {
281 	struct iodesc *s;
282 
283 	TAILQ_FOREACH(s, &sockets, io_link) {
284 		/* search by socket id */
285 		if (socket >= 0) {
286 			if (s->io_id == socket)
287 				break;
288 			continue;
289 		}
290 		/* search for first unused entry */
291 		if (s->io_netif == NULL)
292 			break;
293 	}
294 	return (s);
295 }
296 
297 struct iodesc *
298 socktodesc(int sock)
299 {
300 	struct iodesc *desc;
301 
302 	if (sock < 0)
303 		desc = NULL;
304 	else
305 		desc = socktodesc_impl(sock);
306 
307 	if (desc == NULL)
308 		errno = EBADF;
309 
310 	return (desc);
311 }
312 
313 int
314 netif_open(void *machdep_hint)
315 {
316 	struct iodesc *s;
317 	struct netif *nif;
318 
319 	/* find a free socket */
320 	s = socktodesc_impl(-1);
321 	if (s == NULL) {
322 		struct iodesc *last;
323 
324 		s = calloc(1, sizeof (*s));
325 		if (s == NULL)
326 			return (-1);
327 
328 		last = TAILQ_LAST(&sockets, socket_list);
329 		if (last != NULL)
330 			s->io_id = last->io_id + 1;
331 		TAILQ_INSERT_TAIL(&sockets, s, io_link);
332 	}
333 
334 	netif_init();
335 	nif = netif_select(machdep_hint);
336 	if (!nif)
337 		panic("netboot: no interfaces left untried");
338 	if (netif_probe(nif, machdep_hint)) {
339 		printf("netboot: couldn't probe %s%d\n",
340 		    nif->nif_driver->netif_bname, nif->nif_unit);
341 		errno = EINVAL;
342 		return (-1);
343 	}
344 	netif_attach(nif, s, machdep_hint);
345 
346 	return (s->io_id);
347 }
348 
349 int
350 netif_close(int sock)
351 {
352 	struct iodesc *s, *last;
353 	int err;
354 
355 	err = 0;
356 	s = socktodesc_impl(sock);
357 	if (s == NULL || sock < 0) {
358 		err = EBADF;
359 		return (-1);
360 	}
361 	netif_detach(s->io_netif);
362 	bzero(&s->destip, sizeof (s->destip));
363 	bzero(&s->myip, sizeof (s->myip));
364 	s->destport = 0;
365 	s->myport = 0;
366 	s->xid = 0;
367 	bzero(s->myea, sizeof (s->myea));
368 	s->io_netif = NULL;
369 
370 	/* free unused entries from tail. */
371 	TAILQ_FOREACH_REVERSE_SAFE(last, &sockets, socket_list, io_link, s) {
372 		if (last->io_netif != NULL)
373 			break;
374 		TAILQ_REMOVE(&sockets, last, io_link);
375 		free(last);
376 	}
377 
378 	if (err) {
379 		errno = err;
380 		return (-1);
381 	}
382 
383 	return (0);
384 }
385