[apple/xnu.git] / bsd / kern / kern_newsysctl.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*-
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 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/param.h>
#include <sys/buf.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/systm.h>

/*
struct sysctl_oid_list sysctl__debug_children;
struct sysctl_oid_list sysctl__kern_children;
struct sysctl_oid_list sysctl__net_children;
struct sysctl_oid_list sysctl__sysctl_children;
*/

extern struct sysctl_oid *newsysctl_list[];


static void
sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i);



/*
 * Locking and stats
 */
static struct sysctl_lock {
        int     sl_lock;
        int     sl_want;
        int     sl_locked;
} memlock;

static int sysctl_root SYSCTL_HANDLER_ARGS;

struct sysctl_oid_list sysctl__children; /* root list */

/*
 * Initialization of the MIB tree.
 *
 * Order by number in each list.
 */

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 n;

        /*
         * If this oid has a number OID_AUTO, give it a number which
         * is greater than any current oid.  Make sure it is at least
         * 100 to leave space for pre-assigned oid numbers.
         */
/*      sysctl_sysctl_debug_dump_node(parent, 3); */
        if (oidp->oid_number == OID_AUTO) {
                /* First, find the highest oid in the parent list >99 */
                n = 99;
                SLIST_FOREACH(p, parent, oid_link) {
                        if (p->oid_number > n)
                                n = p->oid_number;
                }
                oidp->oid_number = n + 1;
        }

        /*
         * Insert the oid into the parent's list in order.
         */
        q = NULL;
        SLIST_FOREACH(p, parent, oid_link) {
                if (oidp->oid_number < p->oid_number)
                        break;
                q = p;
        }
        if (q)
                SLIST_INSERT_AFTER(q, oidp, oid_link);
        else
                SLIST_INSERT_HEAD(parent, oidp, oid_link);
}

void sysctl_unregister_oid(struct sysctl_oid *oidp)
{
        SLIST_REMOVE(oidp->oid_parent, oidp, sysctl_oid, oid_link);
}

/*
 * Bulk-register all the oids in a linker_set.
 */
void sysctl_register_set(struct linker_set *lsp)
{
        int count = lsp->ls_length;
        int i;
        for (i = 0; i < count; i++)
                sysctl_register_oid((struct sysctl_oid *) lsp->ls_items[i]);
}

void sysctl_unregister_set(struct linker_set *lsp)
{
        int count = lsp->ls_length;
        int i;
        for (i = 0; i < count; i++)
                sysctl_unregister_oid((struct sysctl_oid *) lsp->ls_items[i]);
}


/*
 * Register OID's from fixed list
 */

void sysctl_register_fixed()
{
    int i = 0;


    while (newsysctl_list[i]) {
/*      printf("Registering %d\n", i); */
        sysctl_register_oid(newsysctl_list[i++]);
    }
}

/*
 * Register the kernel's oids on startup.
 */
struct linker_set sysctl_set;

void sysctl_register_all(void *arg)
{
        sysctl_register_set(&sysctl_set);
}

SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_ANY, 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.
 */

static void
sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i)
{
        int k;
        struct sysctl_oid *oidp;

        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(
                                                oidp->oid_arg1, i+2);
                                }
                                break;
                        case CTLTYPE_INT:    printf(" Int\n"); break;
                        case CTLTYPE_STRING: printf(" String\n"); break;
                        case CTLTYPE_QUAD:   printf(" Quad\n"); break;
                        case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break;
                        default:             printf("\n");
                }

        }
}

static int
sysctl_sysctl_debug SYSCTL_HANDLER_ARGS
{
        sysctl_sysctl_debug_dump_node(&sysctl__children, 0);
        return ENOENT;
}

SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD,
        0, 0, sysctl_sysctl_debug, "-", "");

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];

        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)
                                return (error);
                        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)
                                return (error);

                        namelen--;
                        name++;

                        if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 
                                break;

                        if (oid->oid_handler)
                                break;

                        lsp2 = (struct sysctl_oid_list *)oid->oid_arg1;
                        break;
                }
                lsp = lsp2;
        }
        return (SYSCTL_OUT(req, "", 1));
}

SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD, 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;

        *len = level;
        SLIST_FOREACH(oidp, lsp, oid_link) {
                *next = oidp->oid_number;
                *oidpp = oidp;

                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 = (struct sysctl_oid_list *)oidp->oid_arg1;
                        if (!sysctl_sysctl_next_ls (lsp, 0, 0, next+1, 
                                len, level+1, oidpp))
                                return 0;
                        goto next;
                }

                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 = (struct sysctl_oid_list *)oidp->oid_arg1;
                        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 = (struct sysctl_oid_list *)oidp->oid_arg1;
                if (!sysctl_sysctl_next_ls (lsp, name+1, namelen-1, next+1, 
                        len, level+1, oidpp))
                        return (0);
        next:
                namelen = 1;
                *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];

        i = sysctl_sysctl_next_ls (lsp, name, namelen, newoid, &j, 1, &oid);
        if (i)
                return ENOENT;
        error = SYSCTL_OUT(req, newoid, j * sizeof (int));
        return (error);
}

SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD, sysctl_sysctl_next, "");

static int
name2oid (char *name, int *oid, int *len, struct sysctl_oid **oidpp)
{
        int i;
        struct sysctl_oid *oidp;
        struct sysctl_oid_list *lsp = &sysctl__children;
        char *p;

        if (!*name)
                return ENOENT;

        p = name + strlen(name) - 1 ;
        if (*p == '.')
                *p = '\0';

        *len = 0;

        for (p = name; *p && *p != '.'; p++) 
                ;
        i = *p;
        if (i == '.')
                *p = '\0';

        oidp = SLIST_FIRST(lsp);

        while (oidp && *len < CTL_MAXNAME) {
                if (strcmp(name, oidp->oid_name)) {
                        oidp = SLIST_NEXT(oidp, oid_link);
                        continue;
                }
                *oid++ = oidp->oid_number;
                (*len)++;

                if (!i) {
                        if (oidpp)
                                *oidpp = oidp;
                        return (0);
                }

                if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
                        break;

                if (oidp->oid_handler)
                        break;

                lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
                oidp = SLIST_FIRST(lsp);
                name = p+1;
                for (p = name; *p && *p != '.'; p++) 
                                ;
                i = *p;
                if (i == '.')
                        *p = '\0';
        }
        return ENOENT;
}

static int
sysctl_sysctl_name2oid SYSCTL_HANDLER_ARGS
{
        char *p;
        int error, oid[CTL_MAXNAME], len;
        struct sysctl_oid *op = 0;

        if (!req->newlen) 
                return ENOENT;
        if (req->newlen >= MAXPATHLEN)  /* XXX arbitrary, undocumented */
                return (ENAMETOOLONG);

        p = _MALLOC(req->newlen+1, M_TEMP, M_WAITOK);

        if (!p)
            return ENOMEM;

        error = SYSCTL_IN(req, p, req->newlen);
        if (error) {
                FREE(p, M_TEMP);
                return (error);
        }

        p [req->newlen] = '\0';

        error = name2oid(p, oid, &len, &op);

        FREE(p, M_TEMP);

        if (error)
                return (error);

        error = SYSCTL_OUT(req, oid, len * sizeof *oid);
        return (error);
}

SYSCTL_PROC(_sysctl, 3, name2oid, CTLFLAG_RW|CTLFLAG_ANYBODY, 0, 0, 
        sysctl_sysctl_name2oid, "I", "");

static int
sysctl_sysctl_oidfmt SYSCTL_HANDLER_ARGS
{
        int *name = (int *) arg1, error;
        u_int namelen = arg2;
        int indx;
        struct sysctl_oid *oid;
        struct sysctl_oid_list *lsp = &sysctl__children;

        oid = SLIST_FIRST(lsp);

        indx = 0;
        while (oid && indx < CTL_MAXNAME) {
                if (oid->oid_number == name[indx]) {
                        indx++;
                        if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
                                if (oid->oid_handler)
                                        goto found;
                                if (indx == namelen)
                                        goto found;
                                lsp = (struct sysctl_oid_list *)oid->oid_arg1;
                                oid = SLIST_FIRST(lsp);
                        } else {
                                if (indx != namelen)
                                        return EISDIR;
                                goto found;
                        }
                } else {
                        oid = SLIST_NEXT(oid, oid_link);
                }
        }
        return ENOENT;
found:
        if (!oid->oid_fmt)
                return ENOENT;
        error = SYSCTL_OUT(req, 
                &oid->oid_kind, sizeof(oid->oid_kind));
        if (!error)
                error = SYSCTL_OUT(req, oid->oid_fmt, 
                        strlen(oid->oid_fmt)+1);
        return (error);
}


SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD, sysctl_sysctl_oidfmt, "");

/*
 * Default "handler" functions.
 */

/*
 * Handle an int, signed or unsigned.
 * Two cases:
 *     a variable:  point arg1 at it.
 *     a constant:  pass it in arg2.
 */

int
sysctl_handle_int SYSCTL_HANDLER_ARGS
{
        int error = 0;

        if (arg1)
                error = SYSCTL_OUT(req, arg1, sizeof(int));
        else
                error = SYSCTL_OUT(req, &arg2, sizeof(int));

        if (error || !req->newptr)
                return (error);

        if (!arg1)
                error = EPERM;
        else
                error = SYSCTL_IN(req, arg1, sizeof(int));
        return (error);
}

/*
 * Handle a long, signed or unsigned.  arg1 points to it.
 */

int
sysctl_handle_long SYSCTL_HANDLER_ARGS
{
        int error = 0;

        if (!arg1)
                return (EINVAL);
        error = SYSCTL_OUT(req, arg1, sizeof(long));

        if (error || !req->newptr)
                return (error);

        error = SYSCTL_IN(req, arg1, sizeof(long));
        return (error);
}

/*
 * Handle our generic '\0' terminated 'C' string.
 * Two cases:
 *      a variable string:  point arg1 at it, arg2 is max length.
 *      a constant string:  point arg1 at it, arg2 is zero.
 */

int
sysctl_handle_string SYSCTL_HANDLER_ARGS
{
        int error=0;

        error = SYSCTL_OUT(req, arg1, strlen((char *)arg1)+1);

        if (error || !req->newptr)
                return (error);

        if ((req->newlen - req->newidx) >= arg2) {
                error = EINVAL;
        } else {
                arg2 = (req->newlen - req->newidx);
                error = SYSCTL_IN(req, arg1, arg2);
                ((char *)arg1)[arg2] = '\0';
        }

        return (error);
}

/*
 * Handle any kind of opaque data.
 * arg1 points to it, arg2 is the size.
 */

int
sysctl_handle_opaque SYSCTL_HANDLER_ARGS
{
        int error;

        error = SYSCTL_OUT(req, arg1, arg2);

        if (error || !req->newptr)
                return (error);

        error = SYSCTL_IN(req, arg1, arg2);

        return (error);
}

/*
 * Transfer functions to/from kernel space.
 * XXX: rather untested at this point
 */
static int
sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l)
{
        size_t i = 0;
        int error = 0;

        if (req->oldptr) {
                i = l;
                if (i > req->oldlen - req->oldidx)
                        i = req->oldlen - req->oldidx;
                if (i > 0) {
                        error = copyout(p, (char *)req->oldptr + req->oldidx, i);
                        if (error)
                            return error;
                }
        }
        req->oldidx += l;
        if (req->oldptr && i != l)
                return (ENOMEM);
        return (0);
}

static int
sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l)
{
        if (!req->newptr)
                return 0;
        if (req->newlen - req->newidx < l)
                return (EINVAL);
        copyin((char *)req->newptr + req->newidx, p, l);
        req->newidx += l;
        return (0);
}

int
kernel_sysctl(struct proc *p, int *name, u_int namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval)
{
        int error = 0;
        struct sysctl_req req;

        bzero(&req, sizeof req);

        req.p = p;

        if (oldlenp) {
                req.oldlen = *oldlenp;
        }

        if (old) {
                req.oldptr= old;
        }

        if (newlen) {
                req.newlen = newlen;
                req.newptr = new;
        }

        req.oldfunc = sysctl_old_kernel;
        req.newfunc = sysctl_new_kernel;
        req.lock = 1;

        /* XXX this should probably be done in a general way */
        while (memlock.sl_lock) {
                memlock.sl_want = 1;
                (void) tsleep((caddr_t)&memlock, PRIBIO+1, "sysctl", 0);
                memlock.sl_locked++;
        }
        memlock.sl_lock = 1;

        error = sysctl_root(0, name, namelen, &req);

        if (req.lock == 2)
                vsunlock(req.oldptr, req.oldlen, B_WRITE);

        memlock.sl_lock = 0;

        if (memlock.sl_want) {
                memlock.sl_want = 0;
                wakeup((caddr_t)&memlock);
        }

        if (error && error != ENOMEM)
                return (error);

        if (retval) {
                if (req.oldptr && req.oldidx > req.oldlen)
                        *retval = req.oldlen;
                else
                        *retval = req.oldidx;
        }
        return (error);
}

/*
 * Transfer function to/from user space.
 */
static int
sysctl_old_user(struct sysctl_req *req, const void *p, size_t l)
{
        int error = 0;
        size_t i = 0;

        if (req->oldptr) {
                if (req->oldlen - req->oldidx < l)
                    return (ENOMEM);
                i = l;
                if (i > req->oldlen - req->oldidx)
                        i = req->oldlen - req->oldidx;
                if (i > 0)
                        error = copyout(p, (char *)req->oldptr + req->oldidx,
                                        i);
        }
        req->oldidx += l;
        if (error)
                return (error);
        if (req->oldptr && i < l)
                return (ENOMEM);
        return (0);
}

static int
sysctl_new_user(struct sysctl_req *req, void *p, size_t l)
{
        int error;

        if (!req->newptr)
                return 0;
        if (req->newlen - req->newidx < l)
                return (EINVAL);
        error = copyin((char *)req->newptr + req->newidx, p, l);
        req->newidx += l;
        return (error);
}

/*
 * Traverse our tree, and find the right node, execute whatever it points
 * at, and return the resulting error code.
 */

int
sysctl_root SYSCTL_HANDLER_ARGS
{
        int *name = (int *) arg1;
        u_int namelen = arg2;
        int indx, i;
        struct sysctl_oid *oid;
        struct sysctl_oid_list *lsp = &sysctl__children;
        int error;

        oid = SLIST_FIRST(lsp);

        indx = 0;
        while (oid && indx < CTL_MAXNAME) {
                if (oid->oid_number == name[indx]) {
                        indx++;
                        if (oid->oid_kind & CTLFLAG_NOLOCK)
                                req->lock = 0;
                        if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
                                if (oid->oid_handler)
                                        goto found;
                                if (indx == namelen)
                                        return ENOENT;
                                lsp = (struct sysctl_oid_list *)oid->oid_arg1;
                                oid = SLIST_FIRST(lsp);
                        } else {
                                if (indx != namelen)
                                        return EISDIR;
                                goto found;
                        }
                } else {
                        oid = SLIST_NEXT(oid, oid_link);
                }
        }
        return ENOENT;
found:
        /* If writing isn't allowed */
        if (req->newptr && (!(oid->oid_kind & CTLFLAG_WR) ||
                            ((oid->oid_kind & CTLFLAG_SECURE) && securelevel > 0))) {
                return (EPERM);
        }

        /* Most likely only root can write */
        if (!(oid->oid_kind & CTLFLAG_ANYBODY) &&
            req->newptr && req->p &&
            (error = suser(req->p->p_ucred, &req->p->p_acflag)))
                return (error);

        if (!oid->oid_handler) {
            return EINVAL;
        }

        /*
         * Switch to the NETWORK funnel for CTL_NET and KERN_IPC sysctls
         */

        if (((name[0] == CTL_NET) || ((name[0] == CTL_KERN) &&
                                                       (name[1] == KERN_IPC))))
             thread_funnel_switch(KERNEL_FUNNEL, NETWORK_FUNNEL);

        if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
                i = (oid->oid_handler) (oid,
                                        name + indx, namelen - indx,
                                        req);
        } else {
                i = (oid->oid_handler) (oid,
                                        oid->oid_arg1, oid->oid_arg2,
                                        req);
        }

        /*
         * Switch back to the KERNEL funnel, if necessary
         */

        if (((name[0] == CTL_NET) || ((name[0] == CTL_KERN) &&
                                                       (name[1] == KERN_IPC))))
             thread_funnel_switch(NETWORK_FUNNEL, KERNEL_FUNNEL);

        return (i);
}

#ifndef _SYS_SYSPROTO_H_
struct sysctl_args {
        int     *name;
        u_int   namelen;
        void    *old;
        size_t  *oldlenp;
        void    *new;
        size_t  newlen;
};
#endif

int
/* __sysctl(struct proc *p, struct sysctl_args *uap) */
new_sysctl(struct proc *p, struct sysctl_args *uap)
{
        int error, i, name[CTL_MAXNAME];
        size_t j;

        if (uap->namelen > CTL_MAXNAME || uap->namelen < 2)
                return (EINVAL);

        error = copyin(uap->name, &name, uap->namelen * sizeof(int));
        if (error)
                return (error);

        error = userland_sysctl(p, name, uap->namelen,
                uap->old, uap->oldlenp, 0,
                uap->new, uap->newlen, &j);
        if (error && error != ENOMEM)
                return (error);
        if (uap->oldlenp) {
                i = copyout(&j, uap->oldlenp, sizeof(j));
                if (i)
                        return (i);
        }
        return (error);
}

/*
 * This is used from various compatibility syscalls too.  That's why name
 * must be in kernel space.
 */
int
userland_sysctl(struct proc *p, int *name, u_int namelen, void *old, size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval)
{
        int error = 0;
        struct sysctl_req req, req2;

        bzero(&req, sizeof req);

        req.p = p;

        if (oldlenp) {
                if (inkernel) {
                        req.oldlen = *oldlenp;
                } else {
                        error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp));
                        if (error)
                                return (error);
                }
        }

        if (old) {
                req.oldptr= old;
        }

        if (newlen) {
                req.newlen = newlen;
                req.newptr = new;
        }

        req.oldfunc = sysctl_old_user;
        req.newfunc = sysctl_new_user;
        req.lock = 1;

        do {
            req2 = req;
            error = sysctl_root(0, name, namelen, &req2);
        } while (error == EAGAIN);

        req = req2;

        if (error && error != ENOMEM)
                return (error);

        if (retval) {
                if (req.oldptr && req.oldidx > req.oldlen)
                        *retval = req.oldlen;
                else
                        *retval = req.oldidx;
        }
        return (error);
}
#if 0

#if COMPAT_43
#include <sys/socket.h>
#include <vm/vm_param.h>

#define KINFO_PROC              (0<<8)
#define KINFO_RT                (1<<8)
#define KINFO_VNODE             (2<<8)
#define KINFO_FILE              (3<<8)
#define KINFO_METER             (4<<8)
#define KINFO_LOADAVG           (5<<8)
#define KINFO_CLOCKRATE         (6<<8)

/* Non-standard BSDI extension - only present on their 4.3 net-2 releases */
#define KINFO_BSDI_SYSINFO      (101<<8)

/*
 * XXX this is bloat, but I hope it's better here than on the potentially
 * limited kernel stack...  -Peter
 */

static struct {
        int     bsdi_machine;           /* "i386" on BSD/386 */
/*      ^^^ this is an offset to the string, relative to the struct start */
        char    *pad0;
        long    pad1;
        long    pad2;
        long    pad3;
        u_long  pad4;
        u_long  pad5;
        u_long  pad6;

        int     bsdi_ostype;            /* "BSD/386" on BSD/386 */
        int     bsdi_osrelease;         /* "1.1" on BSD/386 */
        long    pad7;
        long    pad8;
        char    *pad9;

        long    pad10;
        long    pad11;
        int     pad12;
        long    pad13;
        quad_t  pad14;
        long    pad15;

        struct  timeval pad16;
        /* we dont set this, because BSDI's uname used gethostname() instead */
        int     bsdi_hostname;          /* hostname on BSD/386 */

        /* the actual string data is appended here */

} bsdi_si;
/*
 * this data is appended to the end of the bsdi_si structure during copyout.
 * The "char *" offsets are relative to the base of the bsdi_si struct.
 * This contains "FreeBSD\02.0-BUILT-nnnnnn\0i386\0", and these strings
 * should not exceed the length of the buffer here... (or else!! :-)
 */
static char bsdi_strings[80];   /* It had better be less than this! */

#ifndef _SYS_SYSPROTO_H_
struct getkerninfo_args {
        int     op;
        char    *where;
        size_t  *size;
        int     arg;
};
#endif

int
ogetkerninfo(struct proc *p, struct getkerninfo_args *uap)
{
        int error, name[6];
        size_t size;

        switch (uap->op & 0xff00) {

        case KINFO_RT:
                name[0] = CTL_NET;
                name[1] = PF_ROUTE;
                name[2] = 0;
                name[3] = (uap->op & 0xff0000) >> 16;
                name[4] = uap->op & 0xff;
                name[5] = uap->arg;
                error = userland_sysctl(p, name, 6, uap->where, uap->size,
                        0, 0, 0, &size);
                break;

        case KINFO_VNODE:
                name[0] = CTL_KERN;
                name[1] = KERN_VNODE;
                error = userland_sysctl(p, name, 2, uap->where, uap->size,
                        0, 0, 0, &size);
                break;

        case KINFO_PROC:
                name[0] = CTL_KERN;
                name[1] = KERN_PROC;
                name[2] = uap->op & 0xff;
                name[3] = uap->arg;
                error = userland_sysctl(p, name, 4, uap->where, uap->size,
                        0, 0, 0, &size);
                break;

        case KINFO_FILE:
                name[0] = CTL_KERN;
                name[1] = KERN_FILE;
                error = userland_sysctl(p, name, 2, uap->where, uap->size,
                        0, 0, 0, &size);
                break;

        case KINFO_METER:
                name[0] = CTL_VM;
                name[1] = VM_METER;
                error = userland_sysctl(p, name, 2, uap->where, uap->size,
                        0, 0, 0, &size);
                break;

        case KINFO_LOADAVG:
                name[0] = CTL_VM;
                name[1] = VM_LOADAVG;
                error = userland_sysctl(p, name, 2, uap->where, uap->size,
                        0, 0, 0, &size);
                break;

        case KINFO_CLOCKRATE:
                name[0] = CTL_KERN;
                name[1] = KERN_CLOCKRATE;
                error = userland_sysctl(p, name, 2, uap->where, uap->size,
                        0, 0, 0, &size);
                break;

        case KINFO_BSDI_SYSINFO: {
                /*
                 * this is pretty crude, but it's just enough for uname()
                 * from BSDI's 1.x libc to work.
                 *
                 * In particular, it doesn't return the same results when
                 * the supplied buffer is too small.  BSDI's version apparently
                 * will return the amount copied, and set the *size to how
                 * much was needed.  The emulation framework here isn't capable
                 * of that, so we just set both to the amount copied.
                 * BSDI's 2.x product apparently fails with ENOMEM in this
                 * scenario.
                 */

                u_int needed;
                u_int left;
                char *s;

                bzero((char *)&bsdi_si, sizeof(bsdi_si));
                bzero(bsdi_strings, sizeof(bsdi_strings));

                s = bsdi_strings;

                bsdi_si.bsdi_ostype = (s - bsdi_strings) + sizeof(bsdi_si);
                strcpy(s, ostype);
                s += strlen(s) + 1;

                bsdi_si.bsdi_osrelease = (s - bsdi_strings) + sizeof(bsdi_si);
                strcpy(s, osrelease);
                s += strlen(s) + 1;

                bsdi_si.bsdi_machine = (s - bsdi_strings) + sizeof(bsdi_si);
                strcpy(s, machine);
                s += strlen(s) + 1;

                needed = sizeof(bsdi_si) + (s - bsdi_strings);

                if (uap->where == NULL) {
                        /* process is asking how much buffer to supply.. */
                        size = needed;
                        error = 0;
                        break;
                }


                /* if too much buffer supplied, trim it down */
                if (size > needed)
                        size = needed;

                /* how much of the buffer is remaining */
                left = size;

                if ((error = copyout((char *)&bsdi_si, uap->where, left)) != 0)
                        break;

                /* is there any point in continuing? */
                if (left > sizeof(bsdi_si)) {
                        left -= sizeof(bsdi_si);
                        error = copyout(&bsdi_strings,
                                        uap->where + sizeof(bsdi_si), left);
                }
                break;
        }

        default:
                return (EOPNOTSUPP);
        }
        if (error)
                return (error);
        p->p_retval[0] = size;
        if (uap->size)
                error = copyout((caddr_t)&size, (caddr_t)uap->size,
                    sizeof(size));
        return (error);
}
#endif /* COMPAT_43 */

#endif