2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
5 * Copyright (c) 1980, 1986, 1993
6 * The Regents of the University of California. All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * @(#)if.c 8.5 (Berkeley) 1/9/95
36 #include <sys/param.h>
37 #include <sys/eventhandler.h>
38 #include <sys/malloc.h>
39 #include <sys/limits.h>
41 #include <sys/mutex.h>
42 #include <sys/kernel.h>
43 #include <sys/systm.h>
44 #include <sys/types.h>
45 #include <sys/socket.h>
48 #include <net/if_var.h>
49 #include <net/if_clone.h>
50 #include <net/radix.h>
51 #include <net/route.h>
54 /* Current IF_MAXUNIT expands maximum to 5 characters. */
55 #define IFCLOSIZ (IFNAMSIZ - 5)
58 * Structure describing a `cloning' interface.
61 * (c) const until freeing
62 * (d) driver specific data, may need external protection.
63 * (e) locked by if_cloners_mtx
64 * (i) locked by ifc_mtx mtx
67 char ifc_name[IFCLOSIZ]; /* (c) Name of device, e.g. `gif' */
68 struct unrhdr *ifc_unrhdr; /* (c) alloc_unr(9) header */
69 int ifc_maxunit; /* (c) maximum unit number */
70 long ifc_refcnt; /* (i) Reference count. */
71 LIST_HEAD(, ifnet) ifc_iflist; /* (i) List of cloned interfaces */
72 struct mtx ifc_mtx; /* Mutex to protect members. */
74 enum { SIMPLE, ADVANCED } ifc_type; /* (c) */
76 /* (c) Driver specific cloning functions. Called with no locks held. */
78 struct { /* advanced cloner */
79 ifc_match_t *_ifc_match;
80 ifc_create_t *_ifc_create;
81 ifc_destroy_t *_ifc_destroy;
83 struct { /* simple cloner */
84 ifcs_create_t *_ifcs_create;
85 ifcs_destroy_t *_ifcs_destroy;
86 int _ifcs_minifs; /* minimum ifs */
90 #define ifc_match U.A._ifc_match
91 #define ifc_create U.A._ifc_create
92 #define ifc_destroy U.A._ifc_destroy
93 #define ifcs_create U.S._ifcs_create
94 #define ifcs_destroy U.S._ifcs_destroy
95 #define ifcs_minifs U.S._ifcs_minifs
97 LIST_ENTRY(if_clone) ifc_list; /* (e) On list of cloners */
100 static void if_clone_free(struct if_clone *ifc);
101 static int if_clone_createif(struct if_clone *ifc, char *name, size_t len,
104 static int ifc_simple_match(struct if_clone *, const char *);
105 static int ifc_simple_create(struct if_clone *, char *, size_t, caddr_t);
106 static int ifc_simple_destroy(struct if_clone *, struct ifnet *);
108 static struct mtx if_cloners_mtx;
109 MTX_SYSINIT(if_cloners_lock, &if_cloners_mtx, "if_cloners lock", MTX_DEF);
110 static VNET_DEFINE(int, if_cloners_count);
111 VNET_DEFINE(LIST_HEAD(, if_clone), if_cloners);
113 #define V_if_cloners_count VNET(if_cloners_count)
114 #define V_if_cloners VNET(if_cloners)
116 #define IF_CLONERS_LOCK_ASSERT() mtx_assert(&if_cloners_mtx, MA_OWNED)
117 #define IF_CLONERS_LOCK() mtx_lock(&if_cloners_mtx)
118 #define IF_CLONERS_UNLOCK() mtx_unlock(&if_cloners_mtx)
120 #define IF_CLONE_LOCK_INIT(ifc) \
121 mtx_init(&(ifc)->ifc_mtx, "if_clone lock", NULL, MTX_DEF)
122 #define IF_CLONE_LOCK_DESTROY(ifc) mtx_destroy(&(ifc)->ifc_mtx)
123 #define IF_CLONE_LOCK_ASSERT(ifc) mtx_assert(&(ifc)->ifc_mtx, MA_OWNED)
124 #define IF_CLONE_LOCK(ifc) mtx_lock(&(ifc)->ifc_mtx)
125 #define IF_CLONE_UNLOCK(ifc) mtx_unlock(&(ifc)->ifc_mtx)
127 #define IF_CLONE_ADDREF(ifc) \
129 IF_CLONE_LOCK(ifc); \
130 IF_CLONE_ADDREF_LOCKED(ifc); \
131 IF_CLONE_UNLOCK(ifc); \
133 #define IF_CLONE_ADDREF_LOCKED(ifc) \
135 IF_CLONE_LOCK_ASSERT(ifc); \
136 KASSERT((ifc)->ifc_refcnt >= 0, \
137 ("negative refcnt %ld", (ifc)->ifc_refcnt)); \
138 (ifc)->ifc_refcnt++; \
140 #define IF_CLONE_REMREF(ifc) \
142 IF_CLONE_LOCK(ifc); \
143 IF_CLONE_REMREF_LOCKED(ifc); \
145 #define IF_CLONE_REMREF_LOCKED(ifc) \
147 IF_CLONE_LOCK_ASSERT(ifc); \
148 KASSERT((ifc)->ifc_refcnt > 0, \
149 ("bogus refcnt %ld", (ifc)->ifc_refcnt)); \
150 if (--(ifc)->ifc_refcnt == 0) { \
151 IF_CLONE_UNLOCK(ifc); \
152 if_clone_free(ifc); \
154 /* silently free the lock */ \
155 IF_CLONE_UNLOCK(ifc); \
159 #define IFC_IFLIST_INSERT(_ifc, _ifp) \
160 LIST_INSERT_HEAD(&_ifc->ifc_iflist, _ifp, if_clones)
161 #define IFC_IFLIST_REMOVE(_ifc, _ifp) \
162 LIST_REMOVE(_ifp, if_clones)
164 static MALLOC_DEFINE(M_CLONE, "clone", "interface cloning framework");
167 vnet_if_clone_init(void)
170 LIST_INIT(&V_if_cloners);
174 * Lookup and create a clone network interface.
177 if_clone_create(char *name, size_t len, caddr_t params)
179 struct if_clone *ifc;
181 /* Try to find an applicable cloner for this request */
183 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
184 if (ifc->ifc_type == SIMPLE) {
185 if (ifc_simple_match(ifc, name))
188 if (ifc->ifc_match(ifc, name))
192 if (ifc == NULL && !IS_DEFAULT_VNET(curvnet)) {
193 CURVNET_SET_QUIET(vnet0);
194 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
195 if (ifc->ifc_type == SIMPLE) {
196 if (ifc_simple_match(ifc, name))
199 if (ifc->ifc_match(ifc, name))
210 return (if_clone_createif(ifc, name, len, params));
214 * Create a clone network interface.
217 if_clone_createif(struct if_clone *ifc, char *name, size_t len, caddr_t params)
222 if (ifunit(name) != NULL)
225 if (ifc->ifc_type == SIMPLE)
226 err = ifc_simple_create(ifc, name, len, params);
228 err = (*ifc->ifc_create)(ifc, name, len, params);
233 panic("%s: lookup failed for %s", __func__, name);
235 if_addgroup(ifp, ifc->ifc_name);
238 IFC_IFLIST_INSERT(ifc, ifp);
239 IF_CLONE_UNLOCK(ifc);
246 * Lookup and destroy a clone network interface.
249 if_clone_destroy(const char *name)
252 struct if_clone *ifc;
255 ifp = ifunit_ref(name);
259 /* Find the cloner for this interface */
261 LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
262 if (strcmp(ifc->ifc_name, ifp->if_dname) == 0) {
267 if (ifc == NULL && !IS_DEFAULT_VNET(curvnet)) {
268 CURVNET_SET_QUIET(vnet0);
269 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
270 if (ifc->ifc_type == SIMPLE) {
271 if (ifc_simple_match(ifc, name))
274 if (ifc->ifc_match(ifc, name))
286 err = if_clone_destroyif(ifc, ifp);
292 * Destroy a clone network interface.
295 if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
298 struct ifnet *ifcifp;
300 if (ifc->ifc_type == ADVANCED && ifc->ifc_destroy == NULL)
304 * Given that the cloned ifnet might be attached to a different
305 * vnet from where its cloner was registered, we have to
306 * switch to the vnet context of the target vnet.
308 CURVNET_SET_QUIET(ifp->if_vnet);
311 LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
313 IFC_IFLIST_REMOVE(ifc, ifp);
317 IF_CLONE_UNLOCK(ifc);
318 if (ifcifp == NULL) {
320 return (ENXIO); /* ifp is not on the list. */
323 if_delgroup(ifp, ifc->ifc_name);
325 if (ifc->ifc_type == SIMPLE)
326 err = ifc_simple_destroy(ifc, ifp);
328 err = (*ifc->ifc_destroy)(ifc, ifp);
331 if_addgroup(ifp, ifc->ifc_name);
334 IFC_IFLIST_INSERT(ifc, ifp);
335 IF_CLONE_UNLOCK(ifc);
341 static struct if_clone *
342 if_clone_alloc(const char *name, int maxunit)
344 struct if_clone *ifc;
346 KASSERT(name != NULL, ("%s: no name\n", __func__));
348 ifc = malloc(sizeof(struct if_clone), M_CLONE, M_WAITOK | M_ZERO);
349 strncpy(ifc->ifc_name, name, IFCLOSIZ-1);
350 IF_CLONE_LOCK_INIT(ifc);
351 IF_CLONE_ADDREF(ifc);
352 ifc->ifc_maxunit = maxunit ? maxunit : IF_MAXUNIT;
353 ifc->ifc_unrhdr = new_unrhdr(0, ifc->ifc_maxunit, &ifc->ifc_mtx);
354 LIST_INIT(&ifc->ifc_iflist);
360 if_clone_attach(struct if_clone *ifc)
362 struct if_clone *ifc1;
365 LIST_FOREACH(ifc1, &V_if_cloners, ifc_list)
366 if (strcmp(ifc->ifc_name, ifc1->ifc_name) == 0) {
368 IF_CLONE_REMREF(ifc);
371 LIST_INSERT_HEAD(&V_if_cloners, ifc, ifc_list);
372 V_if_cloners_count++;
379 if_clone_advanced(const char *name, u_int maxunit, ifc_match_t match,
380 ifc_create_t create, ifc_destroy_t destroy)
382 struct if_clone *ifc;
384 ifc = if_clone_alloc(name, maxunit);
385 ifc->ifc_type = ADVANCED;
386 ifc->ifc_match = match;
387 ifc->ifc_create = create;
388 ifc->ifc_destroy = destroy;
390 if (if_clone_attach(ifc) != 0)
393 EVENTHANDLER_INVOKE(if_clone_event, ifc);
399 if_clone_simple(const char *name, ifcs_create_t create, ifcs_destroy_t destroy,
402 struct if_clone *ifc;
405 ifc = if_clone_alloc(name, 0);
406 ifc->ifc_type = SIMPLE;
407 ifc->ifcs_create = create;
408 ifc->ifcs_destroy = destroy;
409 ifc->ifcs_minifs = minifs;
411 if (if_clone_attach(ifc) != 0)
414 for (unit = 0; unit < minifs; unit++) {
418 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit);
419 error = if_clone_createif(ifc, name, IFNAMSIZ, NULL);
421 ("%s: failed to create required interface %s",
425 EVENTHANDLER_INVOKE(if_clone_event, ifc);
431 * Unregister a network interface cloner.
434 if_clone_detach(struct if_clone *ifc)
438 LIST_REMOVE(ifc, ifc_list);
439 V_if_cloners_count--;
442 /* Allow all simples to be destroyed */
443 if (ifc->ifc_type == SIMPLE)
444 ifc->ifcs_minifs = 0;
446 /* destroy all interfaces for this cloner */
447 while (!LIST_EMPTY(&ifc->ifc_iflist))
448 if_clone_destroyif(ifc, LIST_FIRST(&ifc->ifc_iflist));
450 IF_CLONE_REMREF(ifc);
454 if_clone_free(struct if_clone *ifc)
457 KASSERT(LIST_EMPTY(&ifc->ifc_iflist),
458 ("%s: ifc_iflist not empty", __func__));
460 IF_CLONE_LOCK_DESTROY(ifc);
461 delete_unrhdr(ifc->ifc_unrhdr);
466 * Provide list of interface cloners to userspace.
469 if_clone_list(struct if_clonereq *ifcr)
471 char *buf, *dst, *outbuf = NULL;
472 struct if_clone *ifc;
473 int buf_count, count, err = 0;
475 if (ifcr->ifcr_count < 0)
480 * Set our internal output buffer size. We could end up not
481 * reporting a cloner that is added between the unlock and lock
482 * below, but that's not a major problem. Not caping our
483 * allocation to the number of cloners actually in the system
484 * could be because that would let arbitrary users cause us to
485 * allocate arbitrary amounts of kernel memory.
487 buf_count = (V_if_cloners_count < ifcr->ifcr_count) ?
488 V_if_cloners_count : ifcr->ifcr_count;
491 outbuf = malloc(IFNAMSIZ*buf_count, M_CLONE, M_WAITOK | M_ZERO);
495 ifcr->ifcr_total = V_if_cloners_count;
496 if ((dst = ifcr->ifcr_buffer) == NULL) {
497 /* Just asking how many there are. */
500 count = (V_if_cloners_count < buf_count) ?
501 V_if_cloners_count : buf_count;
503 for (ifc = LIST_FIRST(&V_if_cloners), buf = outbuf;
504 ifc != NULL && count != 0;
505 ifc = LIST_NEXT(ifc, ifc_list), count--, buf += IFNAMSIZ) {
506 strlcpy(buf, ifc->ifc_name, IFNAMSIZ);
511 if (err == 0 && dst != NULL)
512 err = copyout(outbuf, dst, buf_count*IFNAMSIZ);
514 free(outbuf, M_CLONE);
519 * if_clone_findifc() looks up ifnet from the current
520 * cloner list, and returns ifc if found. Note that ifc_refcnt
524 if_clone_findifc(struct ifnet *ifp)
526 struct if_clone *ifc, *ifc0;
527 struct ifnet *ifcifp;
531 LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
533 LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
536 IF_CLONE_ADDREF_LOCKED(ifc);
540 IF_CLONE_UNLOCK(ifc);
550 * if_clone_addgroup() decrements ifc_refcnt because it is called after
551 * if_clone_findifc().
554 if_clone_addgroup(struct ifnet *ifp, struct if_clone *ifc)
557 if_addgroup(ifp, ifc->ifc_name);
558 IF_CLONE_REMREF(ifc);
562 * A utility function to extract unit numbers from interface names of
565 * Returns 0 on success and an error on failure.
568 ifc_name2unit(const char *name, int *unit)
571 int cutoff = INT_MAX / 10;
572 int cutlim = INT_MAX % 10;
574 for (cp = name; *cp != '\0' && (*cp < '0' || *cp > '9'); cp++);
577 } else if (cp[0] == '0' && cp[1] != '\0') {
578 /* Disallow leading zeroes. */
581 for (*unit = 0; *cp != '\0'; cp++) {
582 if (*cp < '0' || *cp > '9') {
583 /* Bogus unit number. */
586 if (*unit > cutoff ||
587 (*unit == cutoff && *cp - '0' > cutlim))
589 *unit = (*unit * 10) + (*cp - '0');
597 ifc_alloc_unit_specific(struct if_clone *ifc, int *unit)
601 if (*unit > ifc->ifc_maxunit)
604 if (alloc_unr_specific(ifc->ifc_unrhdr, *unit) == -1)
607 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, *unit);
608 if (ifunit(name) != NULL) {
609 free_unr(ifc->ifc_unrhdr, *unit);
613 IF_CLONE_ADDREF(ifc);
619 ifc_alloc_unit_next(struct if_clone *ifc, int *unit)
623 *unit = alloc_unr(ifc->ifc_unrhdr);
627 free_unr(ifc->ifc_unrhdr, *unit);
629 error = ifc_alloc_unit_specific(ifc, unit);
640 ifc_alloc_unit(struct if_clone *ifc, int *unit)
643 return (ifc_alloc_unit_next(ifc, unit));
645 return (ifc_alloc_unit_specific(ifc, unit));
649 ifc_free_unit(struct if_clone *ifc, int unit)
652 free_unr(ifc->ifc_unrhdr, unit);
653 IF_CLONE_REMREF(ifc);
657 ifc_simple_match(struct if_clone *ifc, const char *name)
663 for (cp = name, i = 0; i < strlen(ifc->ifc_name); i++, cp++) {
664 if (ifc->ifc_name[i] != *cp)
668 /* Make sure there's a unit number or nothing after the name */
669 for (; *cp != '\0'; cp++) {
670 if (*cp < '0' || *cp > '9')
678 ifc_simple_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
685 err = ifc_name2unit(name, &unit);
689 wildcard = (unit < 0);
691 err = ifc_alloc_unit(ifc, &unit);
695 err = ifc->ifcs_create(ifc, unit, params);
697 ifc_free_unit(ifc, unit);
701 /* In the wildcard case, we need to update the name. */
703 for (dp = name; *dp != '\0'; dp++);
704 if (snprintf(dp, len - (dp-name), "%d", unit) >
705 len - (dp-name) - 1) {
707 * This can only be a programmer error and
708 * there's no straightforward way to recover if
711 panic("if_clone_create(): interface name too long");
720 ifc_simple_destroy(struct if_clone *ifc, struct ifnet *ifp)
724 unit = ifp->if_dunit;
726 if (unit < ifc->ifcs_minifs)
729 ifc->ifcs_destroy(ifp);
731 ifc_free_unit(ifc, unit);