#include <machine/rtems-bsd-kernel-space.h>
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
* Copyright (c) 1980, 1986, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)if.c 8.5 (Berkeley) 1/9/95
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/eventhandler.h>
#include <sys/malloc.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_clone.h>
#include <net/radix.h>
#include <net/route.h>
#include <net/vnet.h>
/* Current IF_MAXUNIT expands maximum to 5 characters. */
#define IFCLOSIZ (IFNAMSIZ - 5)
/*
* Structure describing a `cloning' interface.
*
* List of locks
* (c) const until freeing
* (d) driver specific data, may need external protection.
* (e) locked by if_cloners_mtx
* (i) locked by ifc_mtx mtx
*/
struct if_clone {
char ifc_name[IFCLOSIZ]; /* (c) Name of device, e.g. `gif' */
struct unrhdr *ifc_unrhdr; /* (c) alloc_unr(9) header */
int ifc_maxunit; /* (c) maximum unit number */
int ifc_flags;
long ifc_refcnt; /* (i) Reference count. */
LIST_HEAD(, ifnet) ifc_iflist; /* (i) List of cloned interfaces */
struct mtx ifc_mtx; /* Mutex to protect members. */
enum { SIMPLE, ADVANCED } ifc_type; /* (c) */
/* (c) Driver specific cloning functions. Called with no locks held. */
union {
struct { /* advanced cloner */
ifc_match_t *_ifc_match;
ifc_create_t *_ifc_create;
ifc_destroy_t *_ifc_destroy;
} A;
struct { /* simple cloner */
ifcs_create_t *_ifcs_create;
ifcs_destroy_t *_ifcs_destroy;
int _ifcs_minifs; /* minimum ifs */
} S;
} U;
#define ifc_match U.A._ifc_match
#define ifc_create U.A._ifc_create
#define ifc_destroy U.A._ifc_destroy
#define ifcs_create U.S._ifcs_create
#define ifcs_destroy U.S._ifcs_destroy
#define ifcs_minifs U.S._ifcs_minifs
LIST_ENTRY(if_clone) ifc_list; /* (e) On list of cloners */
};
static void if_clone_free(struct if_clone *ifc);
static int if_clone_createif(struct if_clone *ifc, char *name, size_t len,
caddr_t params);
static int ifc_simple_match(struct if_clone *, const char *);
static int ifc_simple_create(struct if_clone *, char *, size_t, caddr_t);
static int ifc_simple_destroy(struct if_clone *, struct ifnet *);
static struct mtx if_cloners_mtx;
MTX_SYSINIT(if_cloners_lock, &if_cloners_mtx, "if_cloners lock", MTX_DEF);
VNET_DEFINE_STATIC(int, if_cloners_count);
VNET_DEFINE(LIST_HEAD(, if_clone), if_cloners);
#define V_if_cloners_count VNET(if_cloners_count)
#define V_if_cloners VNET(if_cloners)
#define IF_CLONERS_LOCK_ASSERT() mtx_assert(&if_cloners_mtx, MA_OWNED)
#define IF_CLONERS_LOCK() mtx_lock(&if_cloners_mtx)
#define IF_CLONERS_UNLOCK() mtx_unlock(&if_cloners_mtx)
#define IF_CLONE_LOCK_INIT(ifc) \
mtx_init(&(ifc)->ifc_mtx, "if_clone lock", NULL, MTX_DEF)
#define IF_CLONE_LOCK_DESTROY(ifc) mtx_destroy(&(ifc)->ifc_mtx)
#define IF_CLONE_LOCK_ASSERT(ifc) mtx_assert(&(ifc)->ifc_mtx, MA_OWNED)
#define IF_CLONE_LOCK(ifc) mtx_lock(&(ifc)->ifc_mtx)
#define IF_CLONE_UNLOCK(ifc) mtx_unlock(&(ifc)->ifc_mtx)
#define IF_CLONE_ADDREF(ifc) \
do { \
IF_CLONE_LOCK(ifc); \
IF_CLONE_ADDREF_LOCKED(ifc); \
IF_CLONE_UNLOCK(ifc); \
} while (0)
#define IF_CLONE_ADDREF_LOCKED(ifc) \
do { \
IF_CLONE_LOCK_ASSERT(ifc); \
KASSERT((ifc)->ifc_refcnt >= 0, \
("negative refcnt %ld", (ifc)->ifc_refcnt)); \
(ifc)->ifc_refcnt++; \
} while (0)
#define IF_CLONE_REMREF(ifc) \
do { \
IF_CLONE_LOCK(ifc); \
IF_CLONE_REMREF_LOCKED(ifc); \
} while (0)
#define IF_CLONE_REMREF_LOCKED(ifc) \
do { \
IF_CLONE_LOCK_ASSERT(ifc); \
KASSERT((ifc)->ifc_refcnt > 0, \
("bogus refcnt %ld", (ifc)->ifc_refcnt)); \
if (--(ifc)->ifc_refcnt == 0) { \
IF_CLONE_UNLOCK(ifc); \
if_clone_free(ifc); \
} else { \
/* silently free the lock */ \
IF_CLONE_UNLOCK(ifc); \
} \
} while (0)
#define IFC_IFLIST_INSERT(_ifc, _ifp) \
LIST_INSERT_HEAD(&_ifc->ifc_iflist, _ifp, if_clones)
#define IFC_IFLIST_REMOVE(_ifc, _ifp) \
LIST_REMOVE(_ifp, if_clones)
static MALLOC_DEFINE(M_CLONE, "clone", "interface cloning framework");
void
vnet_if_clone_init(void)
{
LIST_INIT(&V_if_cloners);
}
/*
* Lookup and create a clone network interface.
*/
int
if_clone_create(char *name, size_t len, caddr_t params)
{
struct if_clone *ifc;
/* Try to find an applicable cloner for this request */
IF_CLONERS_LOCK();
LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
if (ifc->ifc_type == SIMPLE) {
if (ifc_simple_match(ifc, name))
break;
} else {
if (ifc->ifc_match(ifc, name))
break;
}
#ifdef VIMAGE
if (ifc == NULL && !IS_DEFAULT_VNET(curvnet)) {
CURVNET_SET_QUIET(vnet0);
LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
if (ifc->ifc_type == SIMPLE) {
if (ifc_simple_match(ifc, name))
break;
} else {
if (ifc->ifc_match(ifc, name))
break;
}
CURVNET_RESTORE();
}
#endif
IF_CLONERS_UNLOCK();
if (ifc == NULL)
return (EINVAL);
return (if_clone_createif(ifc, name, len, params));
}
/*
* Create a clone network interface.
*/
static int
if_clone_createif(struct if_clone *ifc, char *name, size_t len, caddr_t params)
{
int err;
struct ifnet *ifp;
if (ifunit(name) != NULL)
return (EEXIST);
if (ifc->ifc_type == SIMPLE)
err = ifc_simple_create(ifc, name, len, params);
else
err = (*ifc->ifc_create)(ifc, name, len, params);
if (!err) {
ifp = ifunit(name);
if (ifp == NULL)
panic("%s: lookup failed for %s", __func__, name);
if ((ifc->ifc_flags & IFC_NOGROUP) == 0)
if_addgroup(ifp, ifc->ifc_name);
IF_CLONE_LOCK(ifc);
IFC_IFLIST_INSERT(ifc, ifp);
IF_CLONE_UNLOCK(ifc);
}
return (err);
}
/*
* Lookup and destroy a clone network interface.
*/
int
if_clone_destroy(const char *name)
{
int err;
struct if_clone *ifc;
struct ifnet *ifp;
ifp = ifunit_ref(name);
if (ifp == NULL)
return (ENXIO);
/* Find the cloner for this interface */
IF_CLONERS_LOCK();
LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
if (strcmp(ifc->ifc_name, ifp->if_dname) == 0) {
break;
}
}
#ifdef VIMAGE
if (ifc == NULL && !IS_DEFAULT_VNET(curvnet)) {
CURVNET_SET_QUIET(vnet0);
LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
if (ifc->ifc_type == SIMPLE) {
if (ifc_simple_match(ifc, name))
break;
} else {
if (ifc->ifc_match(ifc, name))
break;
}
CURVNET_RESTORE();
}
#endif
IF_CLONERS_UNLOCK();
if (ifc == NULL) {
if_rele(ifp);
return (EINVAL);
}
err = if_clone_destroyif(ifc, ifp);
if_rele(ifp);
return err;
}
/*
* Destroy a clone network interface.
*/
int
if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
{
int err;
struct ifnet *ifcifp;
if (ifc->ifc_type == ADVANCED && ifc->ifc_destroy == NULL)
return(EOPNOTSUPP);
/*
* Given that the cloned ifnet might be attached to a different
* vnet from where its cloner was registered, we have to
* switch to the vnet context of the target vnet.
*/
CURVNET_SET_QUIET(ifp->if_vnet);
IF_CLONE_LOCK(ifc);
LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
if (ifcifp == ifp) {
IFC_IFLIST_REMOVE(ifc, ifp);
break;
}
}
IF_CLONE_UNLOCK(ifc);
if (ifcifp == NULL) {
CURVNET_RESTORE();
return (ENXIO); /* ifp is not on the list. */
}
if ((ifc->ifc_flags & IFC_NOGROUP) == 0)
if_delgroup(ifp, ifc->ifc_name);
if (ifc->ifc_type == SIMPLE)
err = ifc_simple_destroy(ifc, ifp);
else
err = (*ifc->ifc_destroy)(ifc, ifp);
if (err != 0) {
if ((ifc->ifc_flags & IFC_NOGROUP) == 0)
if_addgroup(ifp, ifc->ifc_name);
IF_CLONE_LOCK(ifc);
IFC_IFLIST_INSERT(ifc, ifp);
IF_CLONE_UNLOCK(ifc);
}
CURVNET_RESTORE();
return (err);
}
static struct if_clone *
if_clone_alloc(const char *name, int maxunit)
{
struct if_clone *ifc;
KASSERT(name != NULL, ("%s: no name\n", __func__));
ifc = malloc(sizeof(struct if_clone), M_CLONE, M_WAITOK | M_ZERO);
strncpy(ifc->ifc_name, name, IFCLOSIZ-1);
IF_CLONE_LOCK_INIT(ifc);
IF_CLONE_ADDREF(ifc);
ifc->ifc_maxunit = maxunit ? maxunit : IF_MAXUNIT;
ifc->ifc_unrhdr = new_unrhdr(0, ifc->ifc_maxunit, &ifc->ifc_mtx);
LIST_INIT(&ifc->ifc_iflist);
return (ifc);
}
static int
if_clone_attach(struct if_clone *ifc)
{
struct if_clone *ifc1;
IF_CLONERS_LOCK();
LIST_FOREACH(ifc1, &V_if_cloners, ifc_list)
if (strcmp(ifc->ifc_name, ifc1->ifc_name) == 0) {
IF_CLONERS_UNLOCK();
IF_CLONE_REMREF(ifc);
return (EEXIST);
}
LIST_INSERT_HEAD(&V_if_cloners, ifc, ifc_list);
V_if_cloners_count++;
IF_CLONERS_UNLOCK();
return (0);
}
struct if_clone *
if_clone_advanced(const char *name, u_int maxunit, ifc_match_t match,
ifc_create_t create, ifc_destroy_t destroy)
{
struct if_clone *ifc;
ifc = if_clone_alloc(name, maxunit);
ifc->ifc_type = ADVANCED;
ifc->ifc_match = match;
ifc->ifc_create = create;
ifc->ifc_destroy = destroy;
if (if_clone_attach(ifc) != 0)
return (NULL);
EVENTHANDLER_INVOKE(if_clone_event, ifc);
return (ifc);
}
struct if_clone *
if_clone_simple(const char *name, ifcs_create_t create, ifcs_destroy_t destroy,
u_int minifs)
{
struct if_clone *ifc;
u_int unit;
ifc = if_clone_alloc(name, 0);
ifc->ifc_type = SIMPLE;
ifc->ifcs_create = create;
ifc->ifcs_destroy = destroy;
ifc->ifcs_minifs = minifs;
if (if_clone_attach(ifc) != 0)
return (NULL);
for (unit = 0; unit < minifs; unit++) {
char name[IFNAMSIZ];
int error __unused;
snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit);
error = if_clone_createif(ifc, name, IFNAMSIZ, NULL);
KASSERT(error == 0,
("%s: failed to create required interface %s",
__func__, name));
}
EVENTHANDLER_INVOKE(if_clone_event, ifc);
return (ifc);
}
/*
* Unregister a network interface cloner.
*/
void
if_clone_detach(struct if_clone *ifc)
{
IF_CLONERS_LOCK();
LIST_REMOVE(ifc, ifc_list);
V_if_cloners_count--;
IF_CLONERS_UNLOCK();
/* Allow all simples to be destroyed */
if (ifc->ifc_type == SIMPLE)
ifc->ifcs_minifs = 0;
/* destroy all interfaces for this cloner */
while (!LIST_EMPTY(&ifc->ifc_iflist))
if_clone_destroyif(ifc, LIST_FIRST(&ifc->ifc_iflist));
IF_CLONE_REMREF(ifc);
}
static void
if_clone_free(struct if_clone *ifc)
{
KASSERT(LIST_EMPTY(&ifc->ifc_iflist),
("%s: ifc_iflist not empty", __func__));
IF_CLONE_LOCK_DESTROY(ifc);
delete_unrhdr(ifc->ifc_unrhdr);
free(ifc, M_CLONE);
}
/*
* Provide list of interface cloners to userspace.
*/
int
if_clone_list(struct if_clonereq *ifcr)
{
char *buf, *dst, *outbuf = NULL;
struct if_clone *ifc;
int buf_count, count, err = 0;
if (ifcr->ifcr_count < 0)
return (EINVAL);
IF_CLONERS_LOCK();
/*
* Set our internal output buffer size. We could end up not
* reporting a cloner that is added between the unlock and lock
* below, but that's not a major problem. Not caping our
* allocation to the number of cloners actually in the system
* could be because that would let arbitrary users cause us to
* allocate arbitrary amounts of kernel memory.
*/
buf_count = (V_if_cloners_count < ifcr->ifcr_count) ?
V_if_cloners_count : ifcr->ifcr_count;
IF_CLONERS_UNLOCK();
outbuf = malloc(IFNAMSIZ*buf_count, M_CLONE, M_WAITOK | M_ZERO);
IF_CLONERS_LOCK();
ifcr->ifcr_total = V_if_cloners_count;
if ((dst = ifcr->ifcr_buffer) == NULL) {
/* Just asking how many there are. */
goto done;
}
count = (V_if_cloners_count < buf_count) ?
V_if_cloners_count : buf_count;
for (ifc = LIST_FIRST(&V_if_cloners), buf = outbuf;
ifc != NULL && count != 0;
ifc = LIST_NEXT(ifc, ifc_list), count--, buf += IFNAMSIZ) {
strlcpy(buf, ifc->ifc_name, IFNAMSIZ);
}
done:
IF_CLONERS_UNLOCK();
if (err == 0 && dst != NULL)
err = copyout(outbuf, dst, buf_count*IFNAMSIZ);
if (outbuf != NULL)
free(outbuf, M_CLONE);
return (err);
}
/*
* if_clone_findifc() looks up ifnet from the current
* cloner list, and returns ifc if found. Note that ifc_refcnt
* is incremented.
*/
struct if_clone *
if_clone_findifc(struct ifnet *ifp)
{
struct if_clone *ifc, *ifc0;
struct ifnet *ifcifp;
ifc0 = NULL;
IF_CLONERS_LOCK();
LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
IF_CLONE_LOCK(ifc);
LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
if (ifp == ifcifp) {
ifc0 = ifc;
IF_CLONE_ADDREF_LOCKED(ifc);
break;
}
}
IF_CLONE_UNLOCK(ifc);
if (ifc0 != NULL)
break;
}
IF_CLONERS_UNLOCK();
return (ifc0);
}
/*
* if_clone_addgroup() decrements ifc_refcnt because it is called after
* if_clone_findifc().
*/
void
if_clone_addgroup(struct ifnet *ifp, struct if_clone *ifc)
{
if ((ifc->ifc_flags & IFC_NOGROUP) == 0) {
if_addgroup(ifp, ifc->ifc_name);
IF_CLONE_REMREF(ifc);
}
}
/*
* A utility function to extract unit numbers from interface names of
* the form name###.
*
* Returns 0 on success and an error on failure.
*/
int
ifc_name2unit(const char *name, int *unit)
{
const char *cp;
int cutoff = INT_MAX / 10;
int cutlim = INT_MAX % 10;
for (cp = name; *cp != '\0' && (*cp < '0' || *cp > '9'); cp++);
if (*cp == '\0') {
*unit = -1;
} else if (cp[0] == '0' && cp[1] != '\0') {
/* Disallow leading zeroes. */
return (EINVAL);
} else {
for (*unit = 0; *cp != '\0'; cp++) {
if (*cp < '0' || *cp > '9') {
/* Bogus unit number. */
return (EINVAL);
}
if (*unit > cutoff ||
(*unit == cutoff && *cp - '0' > cutlim))
return (EINVAL);
*unit = (*unit * 10) + (*cp - '0');
}
}
return (0);
}
static int
ifc_alloc_unit_specific(struct if_clone *ifc, int *unit)
{
char name[IFNAMSIZ];
if (*unit > ifc->ifc_maxunit)
return (ENOSPC);
if (alloc_unr_specific(ifc->ifc_unrhdr, *unit) == -1)
return (EEXIST);
snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, *unit);
if (ifunit(name) != NULL) {
free_unr(ifc->ifc_unrhdr, *unit);
return (EEXIST);
}
IF_CLONE_ADDREF(ifc);
return (0);
}
static int
ifc_alloc_unit_next(struct if_clone *ifc, int *unit)
{
int error;
*unit = alloc_unr(ifc->ifc_unrhdr);
if (*unit == -1)
return (ENOSPC);
free_unr(ifc->ifc_unrhdr, *unit);
for (;;) {
error = ifc_alloc_unit_specific(ifc, unit);
if (error != EEXIST)
break;
(*unit)++;
}
return (error);
}
int
ifc_alloc_unit(struct if_clone *ifc, int *unit)
{
if (*unit < 0)
return (ifc_alloc_unit_next(ifc, unit));
else
return (ifc_alloc_unit_specific(ifc, unit));
}
void
ifc_free_unit(struct if_clone *ifc, int unit)
{
free_unr(ifc->ifc_unrhdr, unit);
IF_CLONE_REMREF(ifc);
}
static int
ifc_simple_match(struct if_clone *ifc, const char *name)
{
const char *cp;
int i;
/* Match the name */
for (cp = name, i = 0; i < strlen(ifc->ifc_name); i++, cp++) {
if (ifc->ifc_name[i] != *cp)
return (0);
}
/* Make sure there's a unit number or nothing after the name */
for (; *cp != '\0'; cp++) {
if (*cp < '0' || *cp > '9')
return (0);
}
return (1);
}
static int
ifc_simple_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
{
char *dp;
int wildcard;
int unit;
int err;
err = ifc_name2unit(name, &unit);
if (err != 0)
return (err);
wildcard = (unit < 0);
err = ifc_alloc_unit(ifc, &unit);
if (err != 0)
return (err);
err = ifc->ifcs_create(ifc, unit, params);
if (err != 0) {
ifc_free_unit(ifc, unit);
return (err);
}
/* In the wildcard case, we need to update the name. */
if (wildcard) {
for (dp = name; *dp != '\0'; dp++);
if (snprintf(dp, len - (dp-name), "%d", unit) >
len - (dp-name) - 1) {
/*
* This can only be a programmer error and
* there's no straightforward way to recover if
* it happens.
*/
panic("if_clone_create(): interface name too long");
}
}
return (0);
}
static int
ifc_simple_destroy(struct if_clone *ifc, struct ifnet *ifp)
{
int unit;
unit = ifp->if_dunit;
if (unit < ifc->ifcs_minifs)
return (EINVAL);
ifc->ifcs_destroy(ifp);
ifc_free_unit(ifc, unit);
return (0);
}
const char *
ifc_name(struct if_clone *ifc)
{
return (ifc->ifc_name);
}
void
ifc_flags_set(struct if_clone *ifc, int flags)
{
ifc->ifc_flags = flags;
}
int
ifc_flags_get(struct if_clone *ifc)
{
return (ifc->ifc_flags);
}
