2 * Copyright (c) 1980, 1986, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * @(#)if.c 8.5 (Berkeley) 1/9/95
33 #include <sys/param.h>
34 #include <sys/malloc.h>
35 #include <sys/limits.h>
37 #include <sys/mutex.h>
38 #include <sys/kernel.h>
39 #include <sys/systm.h>
40 #include <sys/types.h>
41 #include <sys/socket.h>
44 #include <net/if_clone.h>
46 #include <net/if_dl.h>
48 #include <net/if_types.h>
49 #include <net/if_var.h>
50 #include <net/radix.h>
51 #include <net/route.h>
53 static void if_clone_free(struct if_clone *ifc);
54 static int if_clone_createif(struct if_clone *ifc, char *name, size_t len);
55 static int if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp);
57 static struct mtx if_cloners_mtx;
58 static int if_cloners_count;
59 LIST_HEAD(, if_clone) if_cloners = LIST_HEAD_INITIALIZER(if_cloners);
61 #define IF_CLONERS_LOCK_INIT() \
62 mtx_init(&if_cloners_mtx, "if_cloners lock", NULL, MTX_DEF)
63 #define IF_CLONERS_LOCK_ASSERT() mtx_assert(&if_cloners_mtx, MA_OWNED)
64 #define IF_CLONERS_LOCK() mtx_lock(&if_cloners_mtx)
65 #define IF_CLONERS_UNLOCK() mtx_unlock(&if_cloners_mtx)
67 #define IF_CLONE_LOCK_INIT(ifc) \
68 mtx_init(&(ifc)->ifc_mtx, "if_clone lock", NULL, MTX_DEF)
69 #define IF_CLONE_LOCK_DESTROY(ifc) mtx_destroy(&(ifc)->ifc_mtx)
70 #define IF_CLONE_LOCK_ASSERT(ifc) mtx_assert(&(ifc)->ifc_mtx, MA_OWNED)
71 #define IF_CLONE_LOCK(ifc) mtx_lock(&(ifc)->ifc_mtx)
72 #define IF_CLONE_UNLOCK(ifc) mtx_unlock(&(ifc)->ifc_mtx)
74 #define IF_CLONE_ADDREF(ifc) \
77 IF_CLONE_ADDREF_LOCKED(ifc); \
78 IF_CLONE_UNLOCK(ifc); \
80 #define IF_CLONE_ADDREF_LOCKED(ifc) \
82 IF_CLONE_LOCK_ASSERT(ifc); \
83 KASSERT((ifc)->ifc_refcnt >= 0, \
84 ("negative refcnt %ld", (ifc)->ifc_refcnt)); \
85 (ifc)->ifc_refcnt++; \
87 #define IF_CLONE_REMREF(ifc) \
90 IF_CLONE_REMREF_LOCKED(ifc); \
92 #define IF_CLONE_REMREF_LOCKED(ifc) \
94 IF_CLONE_LOCK_ASSERT(ifc); \
95 KASSERT((ifc)->ifc_refcnt > 0, \
96 ("bogus refcnt %ld", (ifc)->ifc_refcnt)); \
97 if (--(ifc)->ifc_refcnt == 0) { \
98 IF_CLONE_UNLOCK(ifc); \
101 /* silently free the lock */ \
102 IF_CLONE_UNLOCK(ifc); \
106 #define IFC_IFLIST_INSERT(_ifc, _ifp) \
107 LIST_INSERT_HEAD(&_ifc->ifc_iflist, _ifp, if_clones)
108 #define IFC_IFLIST_REMOVE(_ifc, _ifp) \
109 LIST_REMOVE(_ifp, if_clones)
111 static MALLOC_DEFINE(M_CLONE, "clone", "interface cloning framework");
116 IF_CLONERS_LOCK_INIT();
120 * Lookup and create a clone network interface.
123 if_clone_create(char *name, size_t len)
125 struct if_clone *ifc;
127 /* Try to find an applicable cloner for this request */
129 LIST_FOREACH(ifc, &if_cloners, ifc_list) {
130 if (ifc->ifc_match(ifc, name)) {
139 return (if_clone_createif(ifc, name, len));
143 * Create a clone network interface.
146 if_clone_createif(struct if_clone *ifc, char *name, size_t len)
151 if (ifunit(name) != NULL)
154 err = (*ifc->ifc_create)(ifc, name, len);
159 panic("%s: lookup failed for %s", __func__, name);
162 IFC_IFLIST_INSERT(ifc, ifp);
163 IF_CLONE_UNLOCK(ifc);
170 * Lookup and destroy a clone network interface.
173 if_clone_destroy(const char *name)
175 struct if_clone *ifc;
182 /* Find the cloner for this interface */
184 LIST_FOREACH(ifc, &if_cloners, ifc_list) {
185 if (strcmp(ifc->ifc_name, ifp->if_dname) == 0) {
193 return (if_clone_destroyif(ifc, ifp));
197 * Destroy a clone network interface.
200 if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
204 if (ifc->ifc_destroy == NULL) {
210 IFC_IFLIST_REMOVE(ifc, ifp);
211 IF_CLONE_UNLOCK(ifc);
213 err = (*ifc->ifc_destroy)(ifc, ifp);
217 IFC_IFLIST_INSERT(ifc, ifp);
218 IF_CLONE_UNLOCK(ifc);
226 * Register a network interface cloner.
229 if_clone_attach(struct if_clone *ifc)
234 * Compute bitmap size and allocate it.
236 maxclone = ifc->ifc_maxunit + 1;
238 if ((len << 3) < maxclone)
240 ifc->ifc_units = malloc(len, M_CLONE, M_WAITOK | M_ZERO);
241 ifc->ifc_bmlen = len;
242 IF_CLONE_LOCK_INIT(ifc);
243 IF_CLONE_ADDREF(ifc);
246 LIST_INSERT_HEAD(&if_cloners, ifc, ifc_list);
250 LIST_INIT(&ifc->ifc_iflist);
252 if (ifc->ifc_attach != NULL)
253 (*ifc->ifc_attach)(ifc);
254 EVENTHANDLER_INVOKE(if_clone_event, ifc);
258 * Unregister a network interface cloner.
261 if_clone_detach(struct if_clone *ifc)
263 struct ifc_simple_data *ifcs = ifc->ifc_data;
266 LIST_REMOVE(ifc, ifc_list);
270 /* Allow all simples to be destroyed */
271 if (ifc->ifc_attach == ifc_simple_attach)
272 ifcs->ifcs_minifs = 0;
274 /* destroy all interfaces for this cloner */
275 while (!LIST_EMPTY(&ifc->ifc_iflist))
276 if_clone_destroyif(ifc, LIST_FIRST(&ifc->ifc_iflist));
278 IF_CLONE_REMREF(ifc);
282 if_clone_free(struct if_clone *ifc)
284 for (int bytoff = 0; bytoff < ifc->ifc_bmlen; bytoff++) {
285 KASSERT(ifc->ifc_units[bytoff] == 0x00,
286 ("ifc_units[%d] is not empty", bytoff));
289 KASSERT(LIST_EMPTY(&ifc->ifc_iflist),
290 ("%s: ifc_iflist not empty", __func__));
292 IF_CLONE_LOCK_DESTROY(ifc);
293 free(ifc->ifc_units, M_CLONE);
297 * Provide list of interface cloners to userspace.
300 if_clone_list(struct if_clonereq *ifcr)
302 char *buf, *dst, *outbuf = NULL;
303 struct if_clone *ifc;
304 int buf_count, count, err = 0;
306 if (ifcr->ifcr_count < 0)
311 * Set our internal output buffer size. We could end up not
312 * reporting a cloner that is added between the unlock and lock
313 * below, but that's not a major problem. Not caping our
314 * allocation to the number of cloners actually in the system
315 * could be because that would let arbitrary users cause us to
316 * allocate abritrary amounts of kernel memory.
318 buf_count = (if_cloners_count < ifcr->ifcr_count) ?
319 if_cloners_count : ifcr->ifcr_count;
322 outbuf = malloc(IFNAMSIZ*buf_count, M_CLONE, M_WAITOK | M_ZERO);
326 ifcr->ifcr_total = if_cloners_count;
327 if ((dst = ifcr->ifcr_buffer) == NULL) {
328 /* Just asking how many there are. */
331 count = (if_cloners_count < buf_count) ?
332 if_cloners_count : buf_count;
334 for (ifc = LIST_FIRST(&if_cloners), buf = outbuf;
335 ifc != NULL && count != 0;
336 ifc = LIST_NEXT(ifc, ifc_list), count--, buf += IFNAMSIZ) {
337 strlcpy(buf, ifc->ifc_name, IFNAMSIZ);
343 err = copyout(outbuf, dst, buf_count*IFNAMSIZ);
345 free(outbuf, M_CLONE);
350 * A utility function to extract unit numbers from interface names of
353 * Returns 0 on success and an error on failure.
356 ifc_name2unit(const char *name, int *unit)
359 int cutoff = INT_MAX / 10;
360 int cutlim = INT_MAX % 10;
362 for (cp = name; *cp != '\0' && (*cp < '0' || *cp > '9'); cp++);
365 } else if (cp[0] == '0' && cp[1] != '\0') {
366 /* Disallow leading zeroes. */
369 for (*unit = 0; *cp != '\0'; cp++) {
370 if (*cp < '0' || *cp > '9') {
371 /* Bogus unit number. */
374 if (*unit > cutoff ||
375 (*unit == cutoff && *cp - '0' > cutlim))
377 *unit = (*unit * 10) + (*cp - '0');
385 ifc_alloc_unit(struct if_clone *ifc, int *unit)
387 int wildcard, bytoff, bitoff;
393 wildcard = (*unit < 0);
395 * Find a free unit if none was given.
398 while ((bytoff < ifc->ifc_bmlen)
399 && (ifc->ifc_units[bytoff] == 0xff))
401 if (bytoff >= ifc->ifc_bmlen) {
405 while ((ifc->ifc_units[bytoff] & (1 << bitoff)) != 0)
407 *unit = (bytoff << 3) + bitoff;
410 if (*unit > ifc->ifc_maxunit) {
417 bitoff = *unit - (bytoff << 3);
420 if((ifc->ifc_units[bytoff] & (1 << bitoff)) != 0) {
425 * Allocate the unit in the bitmap.
427 KASSERT((ifc->ifc_units[bytoff] & (1 << bitoff)) == 0,
428 ("%s: bit is already set", __func__));
429 ifc->ifc_units[bytoff] |= (1 << bitoff);
430 IF_CLONE_ADDREF_LOCKED(ifc);
433 IF_CLONE_UNLOCK(ifc);
438 ifc_free_unit(struct if_clone *ifc, int unit)
444 * Compute offset in the bitmap and deallocate the unit.
447 bitoff = unit - (bytoff << 3);
450 KASSERT((ifc->ifc_units[bytoff] & (1 << bitoff)) != 0,
451 ("%s: bit is already cleared", __func__));
452 ifc->ifc_units[bytoff] &= ~(1 << bitoff);
453 IF_CLONE_REMREF_LOCKED(ifc); /* releases lock */
457 ifc_simple_attach(struct if_clone *ifc)
462 struct ifc_simple_data *ifcs = ifc->ifc_data;
464 KASSERT(ifcs->ifcs_minifs - 1 <= ifc->ifc_maxunit,
465 ("%s: %s requested more units than allowed (%d > %d)",
466 __func__, ifc->ifc_name, ifcs->ifcs_minifs,
467 ifc->ifc_maxunit + 1));
469 for (unit = 0; unit < ifcs->ifcs_minifs; unit++) {
470 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit);
471 err = if_clone_createif(ifc, name, IFNAMSIZ);
473 ("%s: failed to create required interface %s",
479 ifc_simple_match(struct if_clone *ifc, const char *name)
485 for (cp = name, i = 0; i < strlen(ifc->ifc_name); i++, cp++) {
486 if (ifc->ifc_name[i] != *cp)
490 /* Make sure there's a unit number or nothing after the name */
491 for (; *cp != '\0'; cp++) {
492 if (*cp < '0' || *cp > '9')
500 ifc_simple_create(struct if_clone *ifc, char *name, size_t len)
506 struct ifc_simple_data *ifcs = ifc->ifc_data;
508 err = ifc_name2unit(name, &unit);
512 wildcard = (unit < 0);
514 err = ifc_alloc_unit(ifc, &unit);
518 err = ifcs->ifcs_create(ifc, unit);
520 ifc_free_unit(ifc, unit);
524 /* In the wildcard case, we need to update the name. */
526 for (dp = name; *dp != '\0'; dp++);
527 if (snprintf(dp, len - (dp-name), "%d", unit) >
528 len - (dp-name) - 1) {
530 * This can only be a programmer error and
531 * there's no straightforward way to recover if
534 panic("if_clone_create(): interface name too long");
543 ifc_simple_destroy(struct if_clone *ifc, struct ifnet *ifp)
546 struct ifc_simple_data *ifcs = ifc->ifc_data;
548 unit = ifp->if_dunit;
550 if (unit < ifcs->ifcs_minifs)
553 ifcs->ifcs_destroy(ifp);
555 ifc_free_unit(ifc, unit);