FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_mib.c

     /*-
      * 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: releng/8.0/sys/kern/kern_mib.c 194118 2009-06-13 15:39:12Z jamie $");
    
    #include "opt_compat.h"
    #include "opt_posix.h"
    #include "opt_config.h"
    
    #include <sys/param.h>
    #include <sys/kernel.h>
    #include <sys/sbuf.h>
    #include <sys/systm.h>
    #include <sys/sysctl.h>
    #include <sys/proc.h>
    #include <sys/lock.h>
    #include <sys/mutex.h>
    #include <sys/jail.h>
    #include <sys/smp.h>
    #include <sys/sx.h>
    #include <sys/unistd.h>
    
    SYSCTL_NODE(, 0,          sysctl, CTLFLAG_RW, 0,
            "Sysctl internal magic");
    SYSCTL_NODE(, CTL_KERN,   kern,   CTLFLAG_RW, 0,
            "High kernel, proc, limits &c");
    SYSCTL_NODE(, CTL_VM,     vm,     CTLFLAG_RW, 0,
            "Virtual memory");
    SYSCTL_NODE(, CTL_VFS,    vfs,     CTLFLAG_RW, 0,
            "File system");
    SYSCTL_NODE(, CTL_NET,    net,    CTLFLAG_RW, 0,
            "Network, (see socket.h)");
    SYSCTL_NODE(, CTL_DEBUG,  debug,  CTLFLAG_RW, 0,
            "Debugging");
    SYSCTL_NODE(_debug, OID_AUTO,  sizeof,  CTLFLAG_RW, 0,
            "Sizeof various things");
    SYSCTL_NODE(, CTL_HW,     hw,     CTLFLAG_RW, 0,
            "hardware");
    SYSCTL_NODE(, CTL_MACHDEP, machdep, CTLFLAG_RW, 0,
            "machine dependent");
    SYSCTL_NODE(, CTL_USER,   user,   CTLFLAG_RW, 0,
            "user-level");
    SYSCTL_NODE(, CTL_P1003_1B,  p1003_1b,   CTLFLAG_RW, 0,
            "p1003_1b, (see p1003_1b.h)");
    
    SYSCTL_NODE(, OID_AUTO,  compat, CTLFLAG_RW, 0,
            "Compatibility code");
    SYSCTL_NODE(, OID_AUTO, security, CTLFLAG_RW, 0, 
            "Security");
    #ifdef REGRESSION
    SYSCTL_NODE(, OID_AUTO, regression, CTLFLAG_RW, 0,
         "Regression test MIB");
    #endif
    
    SYSCTL_STRING(_kern, OID_AUTO, ident, CTLFLAG_RD|CTLFLAG_MPSAFE,
        kern_ident, 0, "Kernel identifier");
    
    SYSCTL_STRING(_kern, KERN_OSRELEASE, osrelease, CTLFLAG_RD|CTLFLAG_MPSAFE,
        osrelease, 0, "Operating system release");
    
    SYSCTL_INT(_kern, KERN_OSREV, osrevision, CTLFLAG_RD,
        0, BSD, "Operating system revision");
    
    SYSCTL_STRING(_kern, KERN_VERSION, version, CTLFLAG_RD|CTLFLAG_MPSAFE,
       version, 0, "Kernel version");
   
   SYSCTL_STRING(_kern, KERN_OSTYPE, ostype, CTLFLAG_RD|CTLFLAG_MPSAFE,
       ostype, 0, "Operating system type");
   
   /*
    * NOTICE: The *userland* release date is available in
    * /usr/include/osreldate.h
    */
   SYSCTL_INT(_kern, KERN_OSRELDATE, osreldate, CTLFLAG_RD,
       &osreldate, 0, "Kernel release date");
   
   SYSCTL_INT(_kern, KERN_MAXPROC, maxproc, CTLFLAG_RDTUN,
       &maxproc, 0, "Maximum number of processes");
   
   SYSCTL_INT(_kern, KERN_MAXPROCPERUID, maxprocperuid, CTLFLAG_RW,
       &maxprocperuid, 0, "Maximum processes allowed per userid");
   
   SYSCTL_INT(_kern, OID_AUTO, maxusers, CTLFLAG_RDTUN,
       &maxusers, 0, "Hint for kernel tuning");
   
   SYSCTL_INT(_kern, KERN_ARGMAX, argmax, CTLFLAG_RD,
       0, ARG_MAX, "Maximum bytes of argument to execve(2)");
   
   SYSCTL_INT(_kern, KERN_POSIX1, posix1version, CTLFLAG_RD,
       0, _POSIX_VERSION, "Version of POSIX attempting to comply to");
   
   SYSCTL_INT(_kern, KERN_NGROUPS, ngroups, CTLFLAG_RD,
       0, NGROUPS_MAX, "Maximum number of groups a user can belong to");
   
   SYSCTL_INT(_kern, KERN_JOB_CONTROL, job_control, CTLFLAG_RD,
       0, 1, "Whether job control is available");
   
   #ifdef _POSIX_SAVED_IDS
   SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
       0, 1, "Whether saved set-group/user ID is available");
   #else
   SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
       0, 0, "Whether saved set-group/user ID is available");
   #endif
   
   char kernelname[MAXPATHLEN] = "/kernel";        /* XXX bloat */
   
   SYSCTL_STRING(_kern, KERN_BOOTFILE, bootfile, CTLFLAG_RW,
       kernelname, sizeof kernelname, "Name of kernel file booted");
   
   SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
       &mp_ncpus, 0, "Number of active CPUs");
   
   SYSCTL_INT(_hw, HW_BYTEORDER, byteorder, CTLFLAG_RD,
       0, BYTE_ORDER, "System byte order");
   
   SYSCTL_INT(_hw, HW_PAGESIZE, pagesize, CTLFLAG_RD,
       0, PAGE_SIZE, "System memory page size");
   
   static int
   sysctl_kern_arnd(SYSCTL_HANDLER_ARGS)
   {
           char buf[256];
           size_t len;
   
           len = req->oldlen;
           if (len > sizeof(buf))
                   len = sizeof(buf);
           arc4rand(buf, len, 0);
           return (SYSCTL_OUT(req, buf, len));
   }
   
   SYSCTL_PROC(_kern, KERN_ARND, arandom,
       CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
       sysctl_kern_arnd, "", "arc4rand");
   
   static int
   sysctl_hw_physmem(SYSCTL_HANDLER_ARGS)
   {
           u_long val;
   
           val = ctob(physmem);
           return (sysctl_handle_long(oidp, &val, 0, req));
   }
   
   SYSCTL_PROC(_hw, HW_PHYSMEM, physmem, CTLTYPE_ULONG | CTLFLAG_RD,
           0, 0, sysctl_hw_physmem, "LU", "");
   
   static int
   sysctl_hw_realmem(SYSCTL_HANDLER_ARGS)
   {
           u_long val;
           val = ctob(realmem);
           return (sysctl_handle_long(oidp, &val, 0, req));
   }
   SYSCTL_PROC(_hw, HW_REALMEM, realmem, CTLTYPE_ULONG | CTLFLAG_RD,
           0, 0, sysctl_hw_realmem, "LU", "");
   static int
   sysctl_hw_usermem(SYSCTL_HANDLER_ARGS)
   {
           u_long val;
   
           val = ctob(physmem - cnt.v_wire_count);
           return (sysctl_handle_long(oidp, &val, 0, req));
   }
   
   SYSCTL_PROC(_hw, HW_USERMEM, usermem, CTLTYPE_ULONG | CTLFLAG_RD,
           0, 0, sysctl_hw_usermem, "LU", "");
   
   SYSCTL_ULONG(_hw, OID_AUTO, availpages, CTLFLAG_RD, &physmem, 0, "");
   
   static char     machine_arch[] = MACHINE_ARCH;
   SYSCTL_STRING(_hw, HW_MACHINE_ARCH, machine_arch, CTLFLAG_RD,
       machine_arch, 0, "System architecture");
   
   static int
   sysctl_hostname(SYSCTL_HANDLER_ARGS)
   {
           struct prison *pr, *cpr;
           size_t pr_offset;
           char tmpname[MAXHOSTNAMELEN];
           int descend, error, len;
   
           /*
            * This function can set: hostname domainname hostuuid.
            * Keep that in mind when comments say "hostname".
            */
           pr_offset = (size_t)arg1;
           len = arg2;
           KASSERT(len <= sizeof(tmpname),
               ("length %d too long for %s", len, __func__));
   
           pr = req->td->td_ucred->cr_prison;
           if (!(pr->pr_allow & PR_ALLOW_SET_HOSTNAME) && req->newptr)
                   return (EPERM);
           /*
            * Make a local copy of hostname to get/set so we don't have to hold
            * the jail mutex during the sysctl copyin/copyout activities.
            */
           mtx_lock(&pr->pr_mtx);
           bcopy((char *)pr + pr_offset, tmpname, len);
           mtx_unlock(&pr->pr_mtx);
   
           error = sysctl_handle_string(oidp, tmpname, len, req);
   
           if (req->newptr != NULL && error == 0) {
                   /*
                    * Copy the locally set hostname to all jails that share
                    * this host info.
                    */
                   sx_slock(&allprison_lock);
                   while (!(pr->pr_flags & PR_HOST))
                           pr = pr->pr_parent;
                   mtx_lock(&pr->pr_mtx);
                   bcopy(tmpname, (char *)pr + pr_offset, len);
                   FOREACH_PRISON_DESCENDANT_LOCKED(pr, cpr, descend)
                           if (cpr->pr_flags & PR_HOST)
                                   descend = 0;
                           else
                                   bcopy(tmpname, (char *)cpr + pr_offset, len);
                   mtx_unlock(&pr->pr_mtx);
                   sx_sunlock(&allprison_lock);
           }
           return (error);
   }
   
   SYSCTL_PROC(_kern, KERN_HOSTNAME, hostname,
       CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
       (void *)(offsetof(struct prison, pr_hostname)), MAXHOSTNAMELEN,
       sysctl_hostname, "A", "Hostname");
   SYSCTL_PROC(_kern, KERN_NISDOMAINNAME, domainname,
       CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
       (void *)(offsetof(struct prison, pr_domainname)), MAXHOSTNAMELEN,
       sysctl_hostname, "A", "Name of the current YP/NIS domain");
   SYSCTL_PROC(_kern, KERN_HOSTUUID, hostuuid,
       CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
       (void *)(offsetof(struct prison, pr_hostuuid)), HOSTUUIDLEN,
       sysctl_hostname, "A", "Host UUID");
   
   static int      regression_securelevel_nonmonotonic = 0;
   
   #ifdef REGRESSION
   SYSCTL_INT(_regression, OID_AUTO, securelevel_nonmonotonic, CTLFLAG_RW,
       &regression_securelevel_nonmonotonic, 0, "securelevel may be lowered");
   #endif
   
   static int
   sysctl_kern_securelvl(SYSCTL_HANDLER_ARGS)
   {
           struct prison *pr, *cpr;
           int descend, error, level;
   
           pr = req->td->td_ucred->cr_prison;
   
           /*
            * Reading the securelevel is easy, since the current jail's level
            * is known to be at least as secure as any higher levels.  Perform
            * a lockless read since the securelevel is an integer.
            */
           level = pr->pr_securelevel;
           error = sysctl_handle_int(oidp, &level, 0, req);
           if (error || !req->newptr)
                   return (error);
           /* Permit update only if the new securelevel exceeds the old. */
           sx_slock(&allprison_lock);
           mtx_lock(&pr->pr_mtx);
           if (!regression_securelevel_nonmonotonic &&
               level < pr->pr_securelevel) {
                   mtx_unlock(&pr->pr_mtx);
                   sx_sunlock(&allprison_lock);
                   return (EPERM);
           }
           pr->pr_securelevel = level;
           /*
            * Set all child jails to be at least this level, but do not lower
            * them (even if regression_securelevel_nonmonotonic).
            */
           FOREACH_PRISON_DESCENDANT_LOCKED(pr, cpr, descend) {
                   if (cpr->pr_securelevel < level)
                           cpr->pr_securelevel = level;
           }
           mtx_unlock(&pr->pr_mtx);
           sx_sunlock(&allprison_lock);
           return (error);
   }
   
   SYSCTL_PROC(_kern, KERN_SECURELVL, securelevel,
       CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, sysctl_kern_securelvl,
       "I", "Current secure level");
   
   #ifdef INCLUDE_CONFIG_FILE
   /* Actual kernel configuration options. */
   extern char kernconfstring[];
   
   static int
   sysctl_kern_config(SYSCTL_HANDLER_ARGS)
   {
           return (sysctl_handle_string(oidp, kernconfstring,
               strlen(kernconfstring), req));
   }
   
   SYSCTL_PROC(_kern, OID_AUTO, conftxt, CTLTYPE_STRING|CTLFLAG_RW, 
       0, 0, sysctl_kern_config, "", "Kernel configuration file");
   #endif
   
   static int
   sysctl_hostid(SYSCTL_HANDLER_ARGS)
   {
           struct prison *pr, *cpr;
           u_long tmpid;
           int descend, error;
   
           /*
            * Like sysctl_hostname, except it operates on a u_long
            * instead of a string, and is used only for hostid.
            */
           pr = req->td->td_ucred->cr_prison;
           if (!(pr->pr_allow & PR_ALLOW_SET_HOSTNAME) && req->newptr)
                   return (EPERM);
           tmpid = pr->pr_hostid;
           error = sysctl_handle_long(oidp, &tmpid, 0, req);
   
           if (req->newptr != NULL && error == 0) {
                   sx_slock(&allprison_lock);
                   while (!(pr->pr_flags & PR_HOST))
                           pr = pr->pr_parent;
                   mtx_lock(&pr->pr_mtx);
                   pr->pr_hostid = tmpid;
                   FOREACH_PRISON_DESCENDANT_LOCKED(pr, cpr, descend)
                           if (cpr->pr_flags & PR_HOST)
                                   descend = 0;
                           else
                                   cpr->pr_hostid = tmpid;
                   mtx_unlock(&pr->pr_mtx);
                   sx_sunlock(&allprison_lock);
           }
           return (error);
   }
   
   SYSCTL_PROC(_kern, KERN_HOSTID, hostid,
       CTLTYPE_ULONG | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
       NULL, 0, sysctl_hostid, "LU", "Host ID");
   
   SYSCTL_NODE(_kern, OID_AUTO, features, CTLFLAG_RD, 0, "Kernel Features");
   
   #ifdef COMPAT_FREEBSD4
   FEATURE(compat_freebsd4, "Compatible with FreeBSD 4");
   #endif
   
   #ifdef COMPAT_FREEBSD5
   FEATURE(compat_freebsd5, "Compatible with FreeBSD 5");
   #endif
   
   #ifdef COMPAT_FREEBSD6
   FEATURE(compat_freebsd6, "Compatible with FreeBSD 6");
   #endif
   
   #ifdef COMPAT_FREEBSD7
   FEATURE(compat_freebsd7, "Compatible with FreeBSD 7");
   #endif
   
   /*
    * This is really cheating.  These actually live in the libc, something
    * which I'm not quite sure is a good idea anyway, but in order for
    * getnext and friends to actually work, we define dummies here.
    */
   SYSCTL_STRING(_user, USER_CS_PATH, cs_path, CTLFLAG_RD,
       "", 0, "PATH that finds all the standard utilities");
   SYSCTL_INT(_user, USER_BC_BASE_MAX, bc_base_max, CTLFLAG_RD,
       0, 0, "Max ibase/obase values in bc(1)");
   SYSCTL_INT(_user, USER_BC_DIM_MAX, bc_dim_max, CTLFLAG_RD,
       0, 0, "Max array size in bc(1)");
   SYSCTL_INT(_user, USER_BC_SCALE_MAX, bc_scale_max, CTLFLAG_RD,
       0, 0, "Max scale value in bc(1)");
   SYSCTL_INT(_user, USER_BC_STRING_MAX, bc_string_max, CTLFLAG_RD,
       0, 0, "Max string length in bc(1)");
   SYSCTL_INT(_user, USER_COLL_WEIGHTS_MAX, coll_weights_max, CTLFLAG_RD,
       0, 0, "Maximum number of weights assigned to an LC_COLLATE locale entry");
   SYSCTL_INT(_user, USER_EXPR_NEST_MAX, expr_nest_max, CTLFLAG_RD, 0, 0, "");
   SYSCTL_INT(_user, USER_LINE_MAX, line_max, CTLFLAG_RD,
       0, 0, "Max length (bytes) of a text-processing utility's input line");
   SYSCTL_INT(_user, USER_RE_DUP_MAX, re_dup_max, CTLFLAG_RD,
       0, 0, "Maximum number of repeats of a regexp permitted");
   SYSCTL_INT(_user, USER_POSIX2_VERSION, posix2_version, CTLFLAG_RD,
       0, 0,
       "The version of POSIX 1003.2 with which the system attempts to comply");
   SYSCTL_INT(_user, USER_POSIX2_C_BIND, posix2_c_bind, CTLFLAG_RD,
       0, 0, "Whether C development supports the C bindings option");
   SYSCTL_INT(_user, USER_POSIX2_C_DEV, posix2_c_dev, CTLFLAG_RD,
       0, 0, "Whether system supports the C development utilities option");
   SYSCTL_INT(_user, USER_POSIX2_CHAR_TERM, posix2_char_term, CTLFLAG_RD,
       0, 0, "");
   SYSCTL_INT(_user, USER_POSIX2_FORT_DEV, posix2_fort_dev, CTLFLAG_RD,
       0, 0, "Whether system supports FORTRAN development utilities");
   SYSCTL_INT(_user, USER_POSIX2_FORT_RUN, posix2_fort_run, CTLFLAG_RD,
       0, 0, "Whether system supports FORTRAN runtime utilities");
   SYSCTL_INT(_user, USER_POSIX2_LOCALEDEF, posix2_localedef, CTLFLAG_RD,
       0, 0, "Whether system supports creation of locales");
   SYSCTL_INT(_user, USER_POSIX2_SW_DEV, posix2_sw_dev, CTLFLAG_RD,
       0, 0, "Whether system supports software development utilities");
   SYSCTL_INT(_user, USER_POSIX2_UPE, posix2_upe, CTLFLAG_RD,
       0, 0, "Whether system supports the user portability utilities");
   SYSCTL_INT(_user, USER_STREAM_MAX, stream_max, CTLFLAG_RD,
       0, 0, "Min Maximum number of streams a process may have open at one time");
   SYSCTL_INT(_user, USER_TZNAME_MAX, tzname_max, CTLFLAG_RD,
       0, 0, "Min Maximum number of types supported for timezone names");
   
   #include <sys/vnode.h>
   SYSCTL_INT(_debug_sizeof, OID_AUTO, vnode, CTLFLAG_RD,
       0, sizeof(struct vnode), "sizeof(struct vnode)");
   
   SYSCTL_INT(_debug_sizeof, OID_AUTO, proc, CTLFLAG_RD,
       0, sizeof(struct proc), "sizeof(struct proc)");
   
   #include <sys/bio.h>
   #include <sys/buf.h>
   SYSCTL_INT(_debug_sizeof, OID_AUTO, bio, CTLFLAG_RD,
       0, sizeof(struct bio), "sizeof(struct bio)");
   SYSCTL_INT(_debug_sizeof, OID_AUTO, buf, CTLFLAG_RD,
       0, sizeof(struct buf), "sizeof(struct buf)");
   
   #include <sys/user.h>
   SYSCTL_INT(_debug_sizeof, OID_AUTO, kinfo_proc, CTLFLAG_RD,
       0, sizeof(struct kinfo_proc), "sizeof(struct kinfo_proc)");
   
   /* XXX compatibility, remove for 6.0 */
   #include <sys/imgact.h>
   #include <sys/imgact_elf.h>
   SYSCTL_INT(_kern, OID_AUTO, fallback_elf_brand, CTLFLAG_RW,
       &__elfN(fallback_brand), sizeof(__elfN(fallback_brand)),
       "compatibility for kern.fallback_elf_brand");

Cache object: c62abc8bf9a3a6cdb4d29007c1df423d