xref: /netbsd-src/sys/netcan/can_pcb.c (revision 8129437f91e6dcc2f4cb06a4243c2d358db49570)
1 /*	$NetBSD: can_pcb.c,v 1.8 2019/07/20 15:34:41 bouyer Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003, 2017 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Robert Swindells and Manuel Bouyer
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: can_pcb.c,v 1.8 2019/07/20 15:34:41 bouyer Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/malloc.h>
38 #include <sys/kmem.h>
39 #include <sys/mbuf.h>
40 #include <sys/protosw.h>
41 #include <sys/socket.h>
42 #include <sys/socketvar.h>
43 #include <sys/ioctl.h>
44 #include <sys/errno.h>
45 #include <sys/time.h>
46 #include <sys/pool.h>
47 #include <sys/proc.h>
48 
49 #include <net/if.h>
50 #include <net/route.h>
51 
52 #include <netcan/can.h>
53 #include <netcan/can_var.h>
54 #include <netcan/can_pcb.h>
55 
56 #define	CANPCBHASH_BIND(table, ifindex) \
57 	&(table)->canpt_bindhashtbl[ \
58 	    (ifindex) & (table)->canpt_bindhash]
59 #define	CANPCBHASH_CONNECT(table, ifindex) \
60 	&(table)->canpt_connecthashtbl[ \
61 	    (ifindex) & (table)->canpt_bindhash]
62 
63 struct pool canpcb_pool;
64 
65 void
can_pcbinit(struct canpcbtable * table,int bindhashsize,int connecthashsize)66 can_pcbinit(struct canpcbtable *table, int bindhashsize, int connecthashsize)
67 {
68 	static int canpcb_pool_initialized;
69 
70 	if (canpcb_pool_initialized == 0) {
71 		pool_init(&canpcb_pool, sizeof(struct canpcb), 0, 0, 0,
72 		    "canpcbpl", NULL, IPL_SOFTNET);
73 		canpcb_pool_initialized = 1;
74 	}
75 
76 	TAILQ_INIT(&table->canpt_queue);
77 	table->canpt_bindhashtbl = hashinit(bindhashsize, HASH_LIST, true,
78 	    &table->canpt_bindhash);
79 	table->canpt_connecthashtbl = hashinit(connecthashsize, HASH_LIST,
80 	    true, &table->canpt_connecthash);
81 }
82 
83 int
can_pcballoc(struct socket * so,void * v)84 can_pcballoc(struct socket *so, void *v)
85 {
86 	struct canpcbtable *table = v;
87 	struct canpcb *canp;
88 	struct can_filter *can_init_filter;
89 	int s;
90 
91 	can_init_filter = kmem_alloc(sizeof(struct can_filter), KM_NOSLEEP);
92 	if (can_init_filter == NULL)
93 		return (ENOBUFS);
94 	can_init_filter->can_id = 0;
95 	can_init_filter->can_mask = 0; /* accept all by default */
96 
97 	s = splnet();
98 	canp = pool_get(&canpcb_pool, PR_NOWAIT);
99 	splx(s);
100 	if (canp == NULL) {
101 		kmem_free(can_init_filter, sizeof(struct can_filter));
102 		return (ENOBUFS);
103 	}
104 	memset(canp, 0, sizeof(*canp));
105 	canp->canp_table = table;
106 	canp->canp_socket = so;
107 	canp->canp_filters = can_init_filter;
108 	canp->canp_nfilters = 1;
109 	mutex_init(&canp->canp_mtx, MUTEX_DEFAULT, IPL_NET);
110 	canp->canp_refcount = 1;
111 
112 	so->so_pcb = canp;
113 	mutex_enter(&canp->canp_mtx);
114 	TAILQ_INSERT_HEAD(&table->canpt_queue, canp, canp_queue);
115 	can_pcbstate(canp, CANP_ATTACHED);
116 	mutex_exit(&canp->canp_mtx);
117 	return (0);
118 }
119 
120 int
can_pcbbind(void * v,struct sockaddr_can * scan,struct lwp * l)121 can_pcbbind(void *v, struct sockaddr_can *scan, struct lwp *l)
122 {
123 	struct canpcb *canp = v;
124 
125 	if (scan->can_family != AF_CAN)
126 		return (EAFNOSUPPORT);
127 	if (scan->can_len != sizeof(*scan))
128 		return EINVAL;
129 	mutex_enter(&canp->canp_mtx);
130 	if (scan->can_ifindex != 0) {
131 		canp->canp_ifp = if_byindex(scan->can_ifindex);
132 		if (canp->canp_ifp == NULL ||
133 		    canp->canp_ifp->if_dlt != DLT_CAN_SOCKETCAN) {
134 			canp->canp_ifp = NULL;
135 			mutex_exit(&canp->canp_mtx);
136 			return (EADDRNOTAVAIL);
137 		}
138 		soisconnected(canp->canp_socket);
139 	} else {
140 		canp->canp_ifp = NULL;
141 		canp->canp_socket->so_state &= ~SS_ISCONNECTED;	/* XXX */
142 	}
143 	can_pcbstate(canp, CANP_BOUND);
144 	mutex_exit(&canp->canp_mtx);
145 	return 0;
146 }
147 
148 /*
149  * Connect from a socket to a specified address.
150  */
151 int
can_pcbconnect(void * v,struct sockaddr_can * scan)152 can_pcbconnect(void *v, struct sockaddr_can *scan)
153 {
154 #if 0
155 	struct canpcb *canp = v;
156 	struct sockaddr_can *ifaddr = NULL;
157 	int error;
158 #endif
159 
160 	if (scan->can_family != AF_CAN)
161 		return (EAFNOSUPPORT);
162 	if (scan->can_len != sizeof(*scan))
163 		return EINVAL;
164 #if 0
165 	mutex_enter(&canp->canp_mtx);
166 	memcpy(&canp->canp_dst, scan, sizeof(struct sockaddr_can));
167 	can_pcbstate(canp, CANP_CONNECTED);
168 	mutex_exit(&canp->canp_mtx);
169 	return 0;
170 #endif
171 	return EOPNOTSUPP;
172 }
173 
174 void
can_pcbdisconnect(void * v)175 can_pcbdisconnect(void *v)
176 {
177 	struct canpcb *canp = v;
178 
179 	mutex_enter(&canp->canp_mtx);
180 	can_pcbstate(canp, CANP_DETACHED);
181 	mutex_exit(&canp->canp_mtx);
182 	if (canp->canp_socket->so_state & SS_NOFDREF)
183 		can_pcbdetach(canp);
184 }
185 
186 void
can_pcbdetach(void * v)187 can_pcbdetach(void *v)
188 {
189 	struct canpcb *canp = v;
190 	struct socket *so = canp->canp_socket;
191 
192 	KASSERT(mutex_owned(softnet_lock));
193 	so->so_pcb = NULL;
194 	mutex_enter(&canp->canp_mtx);
195 	can_pcbstate(canp, CANP_DETACHED);
196 	mutex_exit(&canp->canp_mtx);
197 	can_pcbsetfilter(canp, NULL, 0);
198 	TAILQ_REMOVE(&canp->canp_table->canpt_queue, canp, canp_queue);
199 	sofree(so); /* sofree drops the softnet_lock */
200 	canp_unref(canp);
201 	mutex_enter(softnet_lock);
202 }
203 
204 void
canp_ref(struct canpcb * canp)205 canp_ref(struct canpcb *canp)
206 {
207 	KASSERT(mutex_owned(&canp->canp_mtx));
208 	canp->canp_refcount++;
209 }
210 
211 void
canp_unref(struct canpcb * canp)212 canp_unref(struct canpcb *canp)
213 {
214 	mutex_enter(&canp->canp_mtx);
215 	canp->canp_refcount--;
216 	KASSERT(canp->canp_refcount >= 0);
217 	if (canp->canp_refcount > 0) {
218 		mutex_exit(&canp->canp_mtx);
219 		return;
220 	}
221 	mutex_exit(&canp->canp_mtx);
222 	mutex_destroy(&canp->canp_mtx);
223 	pool_put(&canpcb_pool, canp);
224 }
225 
226 void
can_setsockaddr(struct canpcb * canp,struct sockaddr_can * scan)227 can_setsockaddr(struct canpcb *canp, struct sockaddr_can *scan)
228 {
229 
230 	mutex_enter(&canp->canp_mtx);
231 	memset(scan, 0, sizeof (*scan));
232 	scan->can_family = AF_CAN;
233 	scan->can_len = sizeof(*scan);
234 	if (canp->canp_ifp)
235 		scan->can_ifindex = canp->canp_ifp->if_index;
236 	else
237 		scan->can_ifindex = 0;
238 	mutex_exit(&canp->canp_mtx);
239 }
240 
241 int
can_pcbsetfilter(struct canpcb * canp,struct can_filter * fp,int nfilters)242 can_pcbsetfilter(struct canpcb *canp, struct can_filter *fp, int nfilters)
243 {
244 
245 	struct can_filter *newf;
246 	struct can_filter *oldf;
247 	int oldnf;
248 	int error = 0;
249 
250 	if (nfilters > 0) {
251 		newf =
252 		    kmem_alloc(sizeof(struct can_filter) * nfilters, KM_SLEEP);
253 		memcpy(newf, fp, sizeof(struct can_filter) * nfilters);
254 	} else {
255 		newf = NULL;
256 	}
257 	mutex_enter(&canp->canp_mtx);
258 	oldf = canp->canp_filters;
259 	oldnf = canp->canp_nfilters;
260 	if (newf != NULL && canp->canp_state == CANP_DETACHED) {
261 		error = ECONNRESET;
262 	} else {
263 		canp->canp_filters = newf;
264 		canp->canp_nfilters = nfilters;
265 		newf = NULL;
266 	}
267 	mutex_exit(&canp->canp_mtx);
268 	if (oldf != NULL) {
269 		kmem_free(oldf, sizeof(struct can_filter) * oldnf);
270 	}
271 	if (newf != NULL) {
272 		kmem_free(newf, sizeof(struct can_filter) * nfilters);
273 	}
274 	return error;
275 }
276 
277 
278 
279 #if 0
280 /*
281  * Pass some notification to all connections of a protocol
282  * associated with address dst.  The local address and/or port numbers
283  * may be specified to limit the search.  The "usual action" will be
284  * taken, depending on the ctlinput cmd.  The caller must filter any
285  * cmds that are uninteresting (e.g., no error in the map).
286  * Call the protocol specific routine (if any) to report
287  * any errors for each matching socket.
288  *
289  * Must be called at splsoftnet.
290  */
291 int
292 can_pcbnotify(struct canpcbtable *table, u_int32_t faddr, u_int32_t laddr,
293     int errno, void (*notify)(struct canpcb *, int))
294 {
295 	struct canpcbhead *head;
296 	struct canpcb *canp, *ncanp;
297 	int nmatch;
298 
299 	if (faddr == 0 || notify == 0)
300 		return (0);
301 
302 	nmatch = 0;
303 	head = CANPCBHASH_CONNECT(table, faddr, laddr);
304 	for (canp = LIST_FIRST(head); canp != NULL; canp = ncanp) {
305 		ncanp = LIST_NEXT(canp, canp_hash);
306 		if (canp->canp_faddr == faddr &&
307 		    canp->canp_laddr == laddr) {
308 			(*notify)(canp, errno);
309 			nmatch++;
310 		}
311 	}
312 	return (nmatch);
313 }
314 
315 void
316 can_pcbnotifyall(struct canpcbtable *table, u_int32_t faddr, int errno,
317     void (*notify)(struct canpcb *, int))
318 {
319 	struct canpcb *canp, *ncanp;
320 
321 	if (faddr == 0 || notify == 0)
322 		return;
323 
324 	TAILQ_FOREACH_SAFE(canp, &table->canpt_queue, canp_queue, ncanp) {
325 		if (canp->canp_faddr == faddr)
326 			(*notify)(canp, errno);
327 	}
328 }
329 #endif
330 
331 #if 0
332 void
333 can_pcbpurgeif0(struct canpcbtable *table, struct ifnet *ifp)
334 {
335 	struct canpcb *canp, *ncanp;
336 	struct ip_moptions *imo;
337 	int i, gap;
338 
339 }
340 
341 void
342 can_pcbpurgeif(struct canpcbtable *table, struct ifnet *ifp)
343 {
344 	struct canpcb *canp, *ncanp;
345 
346 	for (canp = CIRCLEQ_FIRST(&table->canpt_queue);
347 	    canp != (void *)&table->canpt_queue;
348 	    canp = ncanp) {
349 		ncanp = CIRCLEQ_NEXT(canp, canp_queue);
350 	}
351 }
352 #endif
353 
354 
355 
356 void
can_pcbstate(struct canpcb * canp,int state)357 can_pcbstate(struct canpcb *canp, int state)
358 {
359 	int ifindex = canp->canp_ifp ? canp->canp_ifp->if_index : 0;
360 	KASSERT(mutex_owned(&canp->canp_mtx));
361 
362 	if (canp->canp_state > CANP_ATTACHED)
363 		LIST_REMOVE(canp, canp_hash);
364 
365 	switch (state) {
366 	case CANP_BOUND:
367 		LIST_INSERT_HEAD(CANPCBHASH_BIND(canp->canp_table,
368 		    ifindex), canp, canp_hash);
369 		break;
370 	case CANP_CONNECTED:
371 		LIST_INSERT_HEAD(CANPCBHASH_CONNECT(canp->canp_table,
372 		    ifindex), canp, canp_hash);
373 		break;
374 	}
375 
376 	canp->canp_state = state;
377 }
378 
379 /*
380  * check mbuf against socket accept filter.
381  * returns true if mbuf is accepted, false otherwise
382  */
383 bool
can_pcbfilter(struct canpcb * canp,struct mbuf * m)384 can_pcbfilter(struct canpcb *canp, struct mbuf *m)
385 {
386 	int i;
387 	struct can_frame *fmp;
388 	struct can_filter *fip;
389 
390 	KASSERT(mutex_owned(&canp->canp_mtx));
391 	KASSERT((m->m_flags & M_PKTHDR) != 0);
392 	KASSERT(m->m_len == m->m_pkthdr.len);
393 
394 	fmp = mtod(m, struct can_frame *);
395 	for (i = 0; i < canp->canp_nfilters; i++) {
396 		fip = &canp->canp_filters[i];
397 		if ((fmp->can_id & fip->can_mask) == fip->can_id)
398 			return true;
399 	}
400 	/* no match */
401 	return false;
402 }
403