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kern_sysctl.c
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/*-
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Mike Karels at Berkeley Software Design, Inc.
*
* Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD
* project, to make these variables more userfriendly.
*
* 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.
* 4. 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.
*
* @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_capsicum.h"
#include "opt_compat.h"
#include "opt_ktrace.h"
#include <sys/param.h>
#include <sys/fail.h>
#include <sys/systm.h>
#include <sys/capsicum.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/malloc.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/jail.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sbuf.h>
#include <sys/sx.h>
#include <sys/sysproto.h>
#include <sys/uio.h>
#ifdef KTRACE
#include <sys/ktrace.h>
#endif
#include <net/vnet.h>
#include <security/mac/mac_framework.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>
static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic");
static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids");
static MALLOC_DEFINE(M_SYSCTLTMP, "sysctltmp", "sysctl temp output buffer");
/*
* The sysctllock protects the MIB tree. It also protects sysctl
* contexts used with dynamic sysctls. The sysctl_register_oid() and
* sysctl_unregister_oid() routines require the sysctllock to already
* be held, so the sysctl_xlock() and sysctl_xunlock() routines are
* provided for the few places in the kernel which need to use that
* API rather than using the dynamic API. Use of the dynamic API is
* strongly encouraged for most code.
*
* The sysctlmemlock is used to limit the amount of user memory wired for
* sysctl requests. This is implemented by serializing any userland
* sysctl requests larger than a single page via an exclusive lock.
*/
static struct sx sysctllock;
static struct sx sysctlmemlock;
#define SYSCTL_XLOCK() sx_xlock(&sysctllock)
#define SYSCTL_XUNLOCK() sx_xunlock(&sysctllock)
#define SYSCTL_SLOCK() sx_slock(&sysctllock)
#define SYSCTL_SUNLOCK() sx_sunlock(&sysctllock)
#define SYSCTL_XLOCKED() sx_xlocked(&sysctllock)
#define SYSCTL_ASSERT_LOCKED() sx_assert(&sysctllock, SA_LOCKED)
#define SYSCTL_ASSERT_XLOCKED() sx_assert(&sysctllock, SA_XLOCKED)
#define SYSCTL_ASSERT_SLOCKED() sx_assert(&sysctllock, SA_SLOCKED)
#define SYSCTL_INIT() sx_init(&sysctllock, "sysctl lock")
#define SYSCTL_SLEEP(ch, wmesg, timo) \
sx_sleep(ch, &sysctllock, 0, wmesg, timo)
static int sysctl_root(SYSCTL_HANDLER_ARGS);
/* Root list */
struct sysctl_oid_list sysctl__children = SLIST_HEAD_INITIALIZER(&sysctl__children);
static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del,
int recurse);
static int sysctl_old_kernel(struct sysctl_req *, const void *, size_t);
static int sysctl_new_kernel(struct sysctl_req *, void *, size_t);
static void
sysctl_lock(bool xlock)
{
if (xlock)
SYSCTL_XLOCK();
else
SYSCTL_SLOCK();
}
static bool
sysctl_unlock(void)
{
bool xlocked;
xlocked = SYSCTL_XLOCKED();
if (xlocked)
SYSCTL_XUNLOCK();
else
SYSCTL_SUNLOCK();
return (xlocked);
}
static struct sysctl_oid *
sysctl_find_oidname(const char *name, struct sysctl_oid_list *list)
{
struct sysctl_oid *oidp;
SYSCTL_ASSERT_LOCKED();
SLIST_FOREACH(oidp, list, oid_link) {
if (strcmp(oidp->oid_name, name) == 0) {
return (oidp);
}
}
return (NULL);
}
/*
* Initialization of the MIB tree.
*
* Order by number in each list.
*/
void
sysctl_xlock(void)
{
SYSCTL_XLOCK();
}
void
sysctl_xunlock(void)
{
SYSCTL_XUNLOCK();
}
static int
sysctl_root_handler_locked(struct sysctl_oid *oid, void *arg1, intptr_t arg2,
struct sysctl_req *req)
{
int error;
bool xlocked;
if (oid->oid_kind & CTLFLAG_DYN)
atomic_add_int(&oid->oid_running, 1);
xlocked = sysctl_unlock();
if (!(oid->oid_kind & CTLFLAG_MPSAFE))
mtx_lock(&Giant);
error = oid->oid_handler(oid, arg1, arg2, req);
if (!(oid->oid_kind & CTLFLAG_MPSAFE))
mtx_unlock(&Giant);
sysctl_lock(xlocked);
if (oid->oid_kind & CTLFLAG_DYN) {
if (atomic_fetchadd_int(&oid->oid_running, -1) == 1 &&
(oid->oid_kind & CTLFLAG_DYING) != 0)
wakeup(&oid->oid_running);
}
return (error);
}
static void
sysctl_load_tunable_by_oid_locked(struct sysctl_oid *oidp)
{
struct sysctl_req req;
struct sysctl_oid *curr;
char *penv = NULL;
char path[64];
ssize_t rem = sizeof(path);
ssize_t len;
int val_int;
long val_long;
int64_t val_64;
quad_t val_quad;
int error;
path[--rem] = 0;
for (curr = oidp; curr != NULL; curr = SYSCTL_PARENT(curr)) {
len = strlen(curr->oid_name);
rem -= len;
if (curr != oidp)
rem -= 1;
if (rem < 0) {
printf("OID path exceeds %d bytes\n", (int)sizeof(path));
return;
}
memcpy(path + rem, curr->oid_name, len);
if (curr != oidp)
path[rem + len] = '.';
}
memset(&req, 0, sizeof(req));
req.td = curthread;
req.oldfunc = sysctl_old_kernel;
req.newfunc = sysctl_new_kernel;
req.lock = REQ_UNWIRED;
switch (oidp->oid_kind & CTLTYPE) {
case CTLTYPE_INT:
if (getenv_int(path + rem, &val_int) == 0)
return;
req.newlen = sizeof(val_int);
req.newptr = &val_int;
break;
case CTLTYPE_UINT:
if (getenv_uint(path + rem, (unsigned int *)&val_int) == 0)
return;
req.newlen = sizeof(val_int);
req.newptr = &val_int;
break;
case CTLTYPE_LONG:
if (getenv_long(path + rem, &val_long) == 0)
return;
req.newlen = sizeof(val_long);
req.newptr = &val_long;
break;
case CTLTYPE_ULONG:
if (getenv_ulong(path + rem, (unsigned long *)&val_long) == 0)
return;
req.newlen = sizeof(val_long);
req.newptr = &val_long;
break;
case CTLTYPE_S64:
if (getenv_quad(path + rem, &val_quad) == 0)
return;
val_64 = val_quad;
req.newlen = sizeof(val_64);
req.newptr = &val_64;
break;
case CTLTYPE_U64:
/* XXX there is no getenv_uquad() */
if (getenv_quad(path + rem, &val_quad) == 0)
return;
val_64 = val_quad;
req.newlen = sizeof(val_64);
req.newptr = &val_64;
break;
case CTLTYPE_STRING:
penv = kern_getenv(path + rem);
if (penv == NULL)
return;
req.newlen = strlen(penv);
req.newptr = penv;
break;
default:
return;
}
error = sysctl_root_handler_locked(oidp, oidp->oid_arg1,
oidp->oid_arg2, &req);
if (error != 0)
printf("Setting sysctl %s failed: %d\n", path + rem, error);
if (penv != NULL)
freeenv(penv);
}
void
sysctl_register_oid(struct sysctl_oid *oidp)
{
struct sysctl_oid_list *parent = oidp->oid_parent;
struct sysctl_oid *p;
struct sysctl_oid *q;
int oid_number;
int timeout = 2;
/*
* First check if another oid with the same name already
* exists in the parent's list.
*/
SYSCTL_ASSERT_XLOCKED();
p = sysctl_find_oidname(oidp->oid_name, parent);
if (p != NULL) {
if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
p->oid_refcnt++;
return;
} else {
printf("can't re-use a leaf (%s)!\n", p->oid_name);
return;
}
}
/* get current OID number */
oid_number = oidp->oid_number;
#if (OID_AUTO >= 0)
#error "OID_AUTO is expected to be a negative value"
#endif
/*
* Any negative OID number qualifies as OID_AUTO. Valid OID
* numbers should always be positive.
*
* NOTE: DO NOT change the starting value here, change it in
* <sys/sysctl.h>, and make sure it is at least 256 to
* accomodate e.g. net.inet.raw as a static sysctl node.
*/
if (oid_number < 0) {
static int newoid;
/*
* By decrementing the next OID number we spend less
* time inserting the OIDs into a sorted list.
*/
if (--newoid < CTL_AUTO_START)
newoid = 0x7fffffff;
oid_number = newoid;
}
/*
* Insert the OID into the parent's list sorted by OID number.
*/
retry:
q = NULL;
SLIST_FOREACH(p, parent, oid_link) {
/* check if the current OID number is in use */
if (oid_number == p->oid_number) {
/* get the next valid OID number */
if (oid_number < CTL_AUTO_START ||
oid_number == 0x7fffffff) {
/* wraparound - restart */
oid_number = CTL_AUTO_START;
/* don't loop forever */
if (!timeout--)
panic("sysctl: Out of OID numbers\n");
goto retry;
} else {
oid_number++;
}
} else if (oid_number < p->oid_number)
break;
q = p;
}
/* check for non-auto OID number collision */
if (oidp->oid_number >= 0 && oidp->oid_number < CTL_AUTO_START &&
oid_number >= CTL_AUTO_START) {
printf("sysctl: OID number(%d) is already in use for '%s'\n",
oidp->oid_number, oidp->oid_name);
}
/* update the OID number, if any */
oidp->oid_number = oid_number;
if (q != NULL)
SLIST_INSERT_AFTER(q, oidp, oid_link);
else
SLIST_INSERT_HEAD(parent, oidp, oid_link);
if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE &&
#ifdef VIMAGE
(oidp->oid_kind & CTLFLAG_VNET) == 0 &&
#endif
(oidp->oid_kind & CTLFLAG_TUN) != 0 &&
(oidp->oid_kind & CTLFLAG_NOFETCH) == 0) {
/* only fetch value once */
oidp->oid_kind |= CTLFLAG_NOFETCH;
/* try to fetch value from kernel environment */
sysctl_load_tunable_by_oid_locked(oidp);
}
}
void
sysctl_unregister_oid(struct sysctl_oid *oidp)
{
struct sysctl_oid *p;
int error;
SYSCTL_ASSERT_XLOCKED();
error = ENOENT;
if (oidp->oid_number == OID_AUTO) {
error = EINVAL;
} else {
SLIST_FOREACH(p, oidp->oid_parent, oid_link) {
if (p == oidp) {
SLIST_REMOVE(oidp->oid_parent, oidp,
sysctl_oid, oid_link);
error = 0;
break;
}
}
}
/*
* This can happen when a module fails to register and is
* being unloaded afterwards. It should not be a panic()
* for normal use.
*/
if (error)
printf("%s: failed to unregister sysctl\n", __func__);
}
/* Initialize a new context to keep track of dynamically added sysctls. */
int
sysctl_ctx_init(struct sysctl_ctx_list *c)
{
if (c == NULL) {
return (EINVAL);
}
/*
* No locking here, the caller is responsible for not adding
* new nodes to a context until after this function has
* returned.
*/
TAILQ_INIT(c);
return (0);
}
/* Free the context, and destroy all dynamic oids registered in this context */
int
sysctl_ctx_free(struct sysctl_ctx_list *clist)
{
struct sysctl_ctx_entry *e, *e1;
int error;
error = 0;
/*
* First perform a "dry run" to check if it's ok to remove oids.
* XXX FIXME
* XXX This algorithm is a hack. But I don't know any
* XXX better solution for now...
*/
SYSCTL_XLOCK();
TAILQ_FOREACH(e, clist, link) {
error = sysctl_remove_oid_locked(e->entry, 0, 0);
if (error)
break;
}
/*
* Restore deregistered entries, either from the end,
* or from the place where error occured.
* e contains the entry that was not unregistered
*/
if (error)
e1 = TAILQ_PREV(e, sysctl_ctx_list, link);
else
e1 = TAILQ_LAST(clist, sysctl_ctx_list);
while (e1 != NULL) {
sysctl_register_oid(e1->entry);
e1 = TAILQ_PREV(e1, sysctl_ctx_list, link);
}
if (error) {
SYSCTL_XUNLOCK();
return(EBUSY);
}
/* Now really delete the entries */
e = TAILQ_FIRST(clist);
while (e != NULL) {
e1 = TAILQ_NEXT(e, link);
error = sysctl_remove_oid_locked(e->entry, 1, 0);
if (error)
panic("sysctl_remove_oid: corrupt tree, entry: %s",
e->entry->oid_name);
free(e, M_SYSCTLOID);
e = e1;
}
SYSCTL_XUNLOCK();
return (error);
}
/* Add an entry to the context */
struct sysctl_ctx_entry *
sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
{
struct sysctl_ctx_entry *e;
SYSCTL_ASSERT_XLOCKED();
if (clist == NULL || oidp == NULL)
return(NULL);
e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK);
e->entry = oidp;
TAILQ_INSERT_HEAD(clist, e, link);
return (e);
}
/* Find an entry in the context */
struct sysctl_ctx_entry *
sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
{
struct sysctl_ctx_entry *e;
SYSCTL_ASSERT_XLOCKED();
if (clist == NULL || oidp == NULL)
return(NULL);
TAILQ_FOREACH(e, clist, link) {
if(e->entry == oidp)
return(e);
}
return (e);
}
/*
* Delete an entry from the context.
* NOTE: this function doesn't free oidp! You have to remove it
* with sysctl_remove_oid().
*/
int
sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
{
struct sysctl_ctx_entry *e;
if (clist == NULL || oidp == NULL)
return (EINVAL);
SYSCTL_XLOCK();
e = sysctl_ctx_entry_find(clist, oidp);
if (e != NULL) {
TAILQ_REMOVE(clist, e, link);
SYSCTL_XUNLOCK();
free(e, M_SYSCTLOID);
return (0);
} else {
SYSCTL_XUNLOCK();
return (ENOENT);
}
}
/*
* Remove dynamically created sysctl trees.
* oidp - top of the tree to be removed
* del - if 0 - just deregister, otherwise free up entries as well
* recurse - if != 0 traverse the subtree to be deleted
*/
int
sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse)
{
int error;
SYSCTL_XLOCK();
error = sysctl_remove_oid_locked(oidp, del, recurse);
SYSCTL_XUNLOCK();
return (error);
}
int
sysctl_remove_name(struct sysctl_oid *parent, const char *name,
int del, int recurse)
{
struct sysctl_oid *p, *tmp;
int error;
error = ENOENT;
SYSCTL_XLOCK();
SLIST_FOREACH_SAFE(p, SYSCTL_CHILDREN(parent), oid_link, tmp) {
if (strcmp(p->oid_name, name) == 0) {
error = sysctl_remove_oid_locked(p, del, recurse);
break;
}
}
SYSCTL_XUNLOCK();
return (error);
}
static int
sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse)
{
struct sysctl_oid *p, *tmp;
int error;
SYSCTL_ASSERT_XLOCKED();
if (oidp == NULL)
return(EINVAL);
if ((oidp->oid_kind & CTLFLAG_DYN) == 0) {
printf("can't remove non-dynamic nodes!\n");
return (EINVAL);
}
/*
* WARNING: normal method to do this should be through
* sysctl_ctx_free(). Use recursing as the last resort
* method to purge your sysctl tree of leftovers...
* However, if some other code still references these nodes,
* it will panic.
*/
if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
if (oidp->oid_refcnt == 1) {
SLIST_FOREACH_SAFE(p,
SYSCTL_CHILDREN(oidp), oid_link, tmp) {
if (!recurse) {
printf("Warning: failed attempt to "
"remove oid %s with child %s\n",
oidp->oid_name, p->oid_name);
return (ENOTEMPTY);
}
error = sysctl_remove_oid_locked(p, del,
recurse);
if (error)
return (error);
}
}
}
if (oidp->oid_refcnt > 1 ) {
oidp->oid_refcnt--;
} else {
if (oidp->oid_refcnt == 0) {
printf("Warning: bad oid_refcnt=%u (%s)!\n",
oidp->oid_refcnt, oidp->oid_name);
return (EINVAL);
}
sysctl_unregister_oid(oidp);
if (del) {
/*
* Wait for all threads running the handler to drain.
* This preserves the previous behavior when the
* sysctl lock was held across a handler invocation,
* and is necessary for module unload correctness.
*/
while (oidp->oid_running > 0) {
oidp->oid_kind |= CTLFLAG_DYING;
SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0);
}
if (oidp->oid_descr)
free(__DECONST(char *, oidp->oid_descr),
M_SYSCTLOID);
free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID);
free(oidp, M_SYSCTLOID);
}
}
return (0);
}
/*
* Create new sysctls at run time.
* clist may point to a valid context initialized with sysctl_ctx_init().
*/
struct sysctl_oid *
sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent,
int number, const char *name, int kind, void *arg1, intptr_t arg2,
int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr)
{
struct sysctl_oid *oidp;
/* You have to hook up somewhere.. */
if (parent == NULL)
return(NULL);
/* Check if the node already exists, otherwise create it */
SYSCTL_XLOCK();
oidp = sysctl_find_oidname(name, parent);
if (oidp != NULL) {
if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
oidp->oid_refcnt++;
/* Update the context */
if (clist != NULL)
sysctl_ctx_entry_add(clist, oidp);
SYSCTL_XUNLOCK();
return (oidp);
} else {
SYSCTL_XUNLOCK();
printf("can't re-use a leaf (%s)!\n", name);
return (NULL);
}
}
oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO);
oidp->oid_parent = parent;
SLIST_INIT(&oidp->oid_children);
oidp->oid_number = number;
oidp->oid_refcnt = 1;
oidp->oid_name = strdup(name, M_SYSCTLOID);
oidp->oid_handler = handler;
oidp->oid_kind = CTLFLAG_DYN | kind;
oidp->oid_arg1 = arg1;
oidp->oid_arg2 = arg2;
oidp->oid_fmt = fmt;
if (descr != NULL)
oidp->oid_descr = strdup(descr, M_SYSCTLOID);
/* Update the context, if used */
if (clist != NULL)
sysctl_ctx_entry_add(clist, oidp);
/* Register this oid */
sysctl_register_oid(oidp);
SYSCTL_XUNLOCK();
return (oidp);
}
/*
* Rename an existing oid.
*/
void
sysctl_rename_oid(struct sysctl_oid *oidp, const char *name)
{
char *newname;
char *oldname;
newname = strdup(name, M_SYSCTLOID);
SYSCTL_XLOCK();
oldname = __DECONST(char *, oidp->oid_name);
oidp->oid_name = newname;
SYSCTL_XUNLOCK();
free(oldname, M_SYSCTLOID);
}
/*
* Reparent an existing oid.
*/
int
sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent)
{
struct sysctl_oid *oidp;
SYSCTL_XLOCK();
if (oid->oid_parent == parent) {
SYSCTL_XUNLOCK();
return (0);
}
oidp = sysctl_find_oidname(oid->oid_name, parent);
if (oidp != NULL) {
SYSCTL_XUNLOCK();
return (EEXIST);
}
sysctl_unregister_oid(oid);
oid->oid_parent = parent;
oid->oid_number = OID_AUTO;
sysctl_register_oid(oid);
SYSCTL_XUNLOCK();
return (0);
}
/*
* Register the kernel's oids on startup.
*/
SET_DECLARE(sysctl_set, struct sysctl_oid);
static void
sysctl_register_all(void *arg)
{
struct sysctl_oid **oidp;
sx_init(&sysctlmemlock, "sysctl mem");
SYSCTL_INIT();
SYSCTL_XLOCK();
SET_FOREACH(oidp, sysctl_set)
sysctl_register_oid(*oidp);
SYSCTL_XUNLOCK();
}
SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, 0);
/*
* "Staff-functions"
*
* These functions implement a presently undocumented interface
* used by the sysctl program to walk the tree, and get the type
* so it can print the value.
* This interface is under work and consideration, and should probably
* be killed with a big axe by the first person who can find the time.
* (be aware though, that the proper interface isn't as obvious as it
* may seem, there are various conflicting requirements.
*
* {0,0} printf the entire MIB-tree.
* {0,1,...} return the name of the "..." OID.
* {0,2,...} return the next OID.
* {0,3} return the OID of the name in "new"
* {0,4,...} return the kind & format info for the "..." OID.
* {0,5,...} return the description the "..." OID.
*/
#ifdef SYSCTL_DEBUG
static void
sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i)
{
int k;
struct sysctl_oid *oidp;
SYSCTL_ASSERT_LOCKED();
SLIST_FOREACH(oidp, l, oid_link) {
for (k=0; k<i; k++)
printf(" ");
printf("%d %s ", oidp->oid_number, oidp->oid_name);
printf("%c%c",
oidp->oid_kind & CTLFLAG_RD ? 'R':' ',
oidp->oid_kind & CTLFLAG_WR ? 'W':' ');
if (oidp->oid_handler)
printf(" *Handler");
switch (oidp->oid_kind & CTLTYPE) {
case CTLTYPE_NODE:
printf(" Node\n");
if (!oidp->oid_handler) {
sysctl_sysctl_debug_dump_node(
SYSCTL_CHILDREN(oidp), i + 2);
}
break;
case CTLTYPE_INT: printf(" Int\n"); break;
case CTLTYPE_UINT: printf(" u_int\n"); break;
case CTLTYPE_LONG: printf(" Long\n"); break;
case CTLTYPE_ULONG: printf(" u_long\n"); break;
case CTLTYPE_STRING: printf(" String\n"); break;
case CTLTYPE_U64: printf(" uint64_t\n"); break;
case CTLTYPE_S64: printf(" int64_t\n"); break;
case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break;
default: printf("\n");
}
}
}
static int
sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS)
{
int error;
error = priv_check(req->td, PRIV_SYSCTL_DEBUG);
if (error)
return (error);
SYSCTL_SLOCK();
sysctl_sysctl_debug_dump_node(&sysctl__children, 0);
SYSCTL_SUNLOCK();
return (ENOENT);
}
SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD|CTLFLAG_MPSAFE,
0, 0, sysctl_sysctl_debug, "-", "");
#endif
static int
sysctl_sysctl_name(SYSCTL_HANDLER_ARGS)
{
int *name = (int *) arg1;
u_int namelen = arg2;
int error = 0;
struct sysctl_oid *oid;
struct sysctl_oid_list *lsp = &sysctl__children, *lsp2;
char buf[10];
SYSCTL_SLOCK();
while (namelen) {
if (!lsp) {
snprintf(buf,sizeof(buf),"%d",*name);
if (req->oldidx)
error = SYSCTL_OUT(req, ".", 1);
if (!error)
error = SYSCTL_OUT(req, buf, strlen(buf));
if (error)
goto out;
namelen--;
name++;
continue;
}
lsp2 = 0;
SLIST_FOREACH(oid, lsp, oid_link) {
if (oid->oid_number != *name)
continue;
if (req->oldidx)
error = SYSCTL_OUT(req, ".", 1);
if (!error)
error = SYSCTL_OUT(req, oid->oid_name,
strlen(oid->oid_name));
if (error)
goto out;
namelen--;
name++;
if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE)
break;
if (oid->oid_handler)
break;
lsp2 = SYSCTL_CHILDREN(oid);
break;
}
lsp = lsp2;
}
error = SYSCTL_OUT(req, "", 1);
out:
SYSCTL_SUNLOCK();
return (error);
}
/*
* XXXRW/JA: Shouldn't return name data for nodes that we don't permit in
* capability mode.
*/
static SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD,
sysctl_sysctl_name, "");
static int
sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen,
int *next, int *len, int level, struct sysctl_oid **oidpp)
{
struct sysctl_oid *oidp;
SYSCTL_ASSERT_LOCKED();
*len = level;
SLIST_FOREACH(oidp, lsp, oid_link) {
*next = oidp->oid_number;
*oidpp = oidp;
if (oidp->oid_kind & CTLFLAG_SKIP)
continue;
if (!namelen) {
if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
return (0);
if (oidp->oid_handler)
/* We really should call the handler here...*/
return (0);
lsp = SYSCTL_CHILDREN(oidp);
if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1,
len, level+1, oidpp))
return (0);
goto emptynode;
}
if (oidp->oid_number < *name)
continue;
if (oidp->oid_number > *name) {
if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
return (0);
if (oidp->oid_handler)
return (0);
lsp = SYSCTL_CHILDREN(oidp);
if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1,
next+1, len, level+1, oidpp))
return (0);
goto next;
}
if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
continue;
if (oidp->oid_handler)
continue;
lsp = SYSCTL_CHILDREN(oidp);
if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1,
len, level+1, oidpp))
return (0);
next:
namelen = 1;
emptynode:
*len = level;
}
return (1);
}
static int
sysctl_sysctl_next(SYSCTL_HANDLER_ARGS)
{
int *name = (int *) arg1;
u_int namelen = arg2;
int i, j, error;
struct sysctl_oid *oid;
struct sysctl_oid_list *lsp = &sysctl__children;
int newoid[CTL_MAXNAME];
SYSCTL_SLOCK();
i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid);
SYSCTL_SUNLOCK();
if (i)
return (ENOENT);
error = SYSCTL_OUT(req, newoid, j * sizeof (int));
return (error);
}
/*
* XXXRW/JA: Shouldn't return next data for nodes that we don't permit in
* capability mode.
*/
static SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD,
sysctl_sysctl_next, "");
static int