sys/kern/kern_mib.c

   1 /*-
   2  * Copyright (c) 1982, 1986, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Mike Karels at Berkeley Software Design, Inc.
   7  *
   8  * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD
   9  * project, to make these variables more userfriendly.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  *      @(#)kern_sysctl.c       8.4 (Berkeley) 4/14/94
  36  */
  37
  38 #include <sys/cdefs.h>
  39 __FBSDID("$FreeBSD$");
  40
  41 #include "opt_compat.h"
  42 #include "opt_posix.h"
  43 #include "opt_config.h"
  44
  45 #include <sys/param.h>
  46 #include <sys/kernel.h>
  47 #include <sys/sbuf.h>
  48 #include <sys/systm.h>
  49 #include <sys/sysctl.h>
  50 #include <sys/proc.h>
  51 #include <sys/lock.h>
  52 #include <sys/mutex.h>
  53 #include <sys/jail.h>
  54 #include <sys/smp.h>
  55 #include <sys/unistd.h>
  56 #include <sys/vimage.h>
  57
  58 SYSCTL_NODE(, 0,          sysctl, CTLFLAG_RW, 0,
  59         "Sysctl internal magic");
  60 SYSCTL_NODE(, CTL_KERN,   kern,   CTLFLAG_RW, 0,
  61         "High kernel, proc, limits &c");
  62 SYSCTL_NODE(, CTL_VM,     vm,     CTLFLAG_RW, 0,
  63         "Virtual memory");
  64 SYSCTL_NODE(, CTL_VFS,    vfs,     CTLFLAG_RW, 0,
  65         "File system");
  66 SYSCTL_NODE(, CTL_NET,    net,    CTLFLAG_RW, 0,
  67         "Network, (see socket.h)");
  68 SYSCTL_NODE(, CTL_DEBUG,  debug,  CTLFLAG_RW, 0,
  69         "Debugging");
  70 SYSCTL_NODE(_debug, OID_AUTO,  sizeof,  CTLFLAG_RW, 0,
  71         "Sizeof various things");
  72 SYSCTL_NODE(, CTL_HW,     hw,     CTLFLAG_RW, 0,
  73         "hardware");
  74 SYSCTL_NODE(, CTL_MACHDEP, machdep, CTLFLAG_RW, 0,
  75         "machine dependent");
  76 SYSCTL_NODE(, CTL_USER,   user,   CTLFLAG_RW, 0,
  77         "user-level");
  78 SYSCTL_NODE(, CTL_P1003_1B,  p1003_1b,   CTLFLAG_RW, 0,
  79         "p1003_1b, (see p1003_1b.h)");
  80
  81 SYSCTL_NODE(, OID_AUTO,  compat, CTLFLAG_RW, 0,
  82         "Compatibility code");
  83 SYSCTL_NODE(, OID_AUTO, security, CTLFLAG_RW, 0,
  84         "Security");
  85 #ifdef REGRESSION
  86 SYSCTL_NODE(, OID_AUTO, regression, CTLFLAG_RW, 0,
  87      "Regression test MIB");
  88 #endif
  89
  90 SYSCTL_STRING(_kern, OID_AUTO, ident, CTLFLAG_RD,
  91     kern_ident, 0, "Kernel identifier");
  92
  93 SYSCTL_STRING(_kern, KERN_OSRELEASE, osrelease, CTLFLAG_RD,
  94     osrelease, 0, "Operating system release");
  95
  96 SYSCTL_INT(_kern, KERN_OSREV, osrevision, CTLFLAG_RD,
  97     0, BSD, "Operating system revision");
  98
  99 SYSCTL_STRING(_kern, KERN_VERSION, version, CTLFLAG_RD,
 100     version, 0, "Kernel version");
 101
 102 SYSCTL_STRING(_kern, KERN_OSTYPE, ostype, CTLFLAG_RD,
 103     ostype, 0, "Operating system type");
 104
 105 /*
 106  * NOTICE: The *userland* release date is available in
 107  * /usr/include/osreldate.h
 108  */
 109 SYSCTL_INT(_kern, KERN_OSRELDATE, osreldate, CTLFLAG_RD,
 110     &osreldate, 0, "Kernel release date");
 111
 112 SYSCTL_INT(_kern, KERN_MAXPROC, maxproc, CTLFLAG_RDTUN,
 113     &maxproc, 0, "Maximum number of processes");
 114
 115 SYSCTL_INT(_kern, KERN_MAXPROCPERUID, maxprocperuid, CTLFLAG_RW,
 116     &maxprocperuid, 0, "Maximum processes allowed per userid");
 117
 118 SYSCTL_INT(_kern, OID_AUTO, maxusers, CTLFLAG_RDTUN,
 119     &maxusers, 0, "Hint for kernel tuning");
 120
 121 SYSCTL_INT(_kern, KERN_ARGMAX, argmax, CTLFLAG_RD,
 122     0, ARG_MAX, "Maximum bytes of argument to execve(2)");
 123
 124 SYSCTL_INT(_kern, KERN_POSIX1, posix1version, CTLFLAG_RD,
 125     0, _POSIX_VERSION, "Version of POSIX attempting to comply to");
 126
 127 SYSCTL_INT(_kern, KERN_NGROUPS, ngroups, CTLFLAG_RD,
 128     0, NGROUPS_MAX, "Maximum number of groups a user can belong to");
 129
 130 SYSCTL_INT(_kern, KERN_JOB_CONTROL, job_control, CTLFLAG_RD,
 131     0, 1, "Whether job control is available");
 132
 133 #ifdef _POSIX_SAVED_IDS
 134 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
 135     0, 1, "Whether saved set-group/user ID is available");
 136 #else
 137 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
 138     0, 0, "Whether saved set-group/user ID is available");
 139 #endif
 140
 141 char kernelname[MAXPATHLEN] = "/kernel";        /* XXX bloat */
 142
 143 SYSCTL_STRING(_kern, KERN_BOOTFILE, bootfile, CTLFLAG_RW,
 144     kernelname, sizeof kernelname, "Name of kernel file booted");
 145
 146 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
 147     &mp_ncpus, 0, "Number of active CPUs");
 148
 149 SYSCTL_INT(_hw, HW_BYTEORDER, byteorder, CTLFLAG_RD,
 150     0, BYTE_ORDER, "System byte order");
 151
 152 SYSCTL_INT(_hw, HW_PAGESIZE, pagesize, CTLFLAG_RD,
 153     0, PAGE_SIZE, "System memory page size");
 154
 155 static int
 156 sysctl_kern_arnd(SYSCTL_HANDLER_ARGS)
 157 {
 158         char buf[256];
 159         size_t len;
 160
 161         len = req->oldlen;
 162         if (len > sizeof(buf))
 163                 len = sizeof(buf);
 164         arc4rand(buf, len, 0);
 165         return (SYSCTL_OUT(req, buf, len));
 166 }
 167
 168 SYSCTL_PROC(_kern, KERN_ARND, arandom, CTLTYPE_OPAQUE | CTLFLAG_RD,
 169     NULL, 0, sysctl_kern_arnd, "", "arc4rand");
 170
 171 static int
 172 sysctl_hw_physmem(SYSCTL_HANDLER_ARGS)
 173 {
 174         u_long val;
 175
 176         val = ctob(physmem);
 177         return (sysctl_handle_long(oidp, &val, 0, req));
 178 }
 179
 180 SYSCTL_PROC(_hw, HW_PHYSMEM, physmem, CTLTYPE_ULONG | CTLFLAG_RD,
 181         0, 0, sysctl_hw_physmem, "LU", "");
 182
 183 static int
 184 sysctl_hw_realmem(SYSCTL_HANDLER_ARGS)
 185 {
 186         u_long val;
 187         val = ctob(realmem);
 188         return (sysctl_handle_long(oidp, &val, 0, req));
 189 }
 190 SYSCTL_PROC(_hw, HW_REALMEM, realmem, CTLTYPE_ULONG | CTLFLAG_RD,
 191         0, 0, sysctl_hw_realmem, "LU", "");
 192 static int
 193 sysctl_hw_usermem(SYSCTL_HANDLER_ARGS)
 194 {
 195         u_long val;
 196
 197         val = ctob(physmem - cnt.v_wire_count);
 198         return (sysctl_handle_long(oidp, &val, 0, req));
 199 }
 200
 201 SYSCTL_PROC(_hw, HW_USERMEM, usermem, CTLTYPE_ULONG | CTLFLAG_RD,
 202         0, 0, sysctl_hw_usermem, "LU", "");
 203
 204 SYSCTL_ULONG(_hw, OID_AUTO, availpages, CTLFLAG_RD, &physmem, 0, "");
 205
 206 static char     machine_arch[] = MACHINE_ARCH;
 207 SYSCTL_STRING(_hw, HW_MACHINE_ARCH, machine_arch, CTLFLAG_RD,
 208     machine_arch, 0, "System architecture");
 209
 210 char hostname[MAXHOSTNAMELEN];
 211
 212 /*
 213  * This mutex is used to protect the hostname and domainname variables, and
 214  * perhaps in the future should also protect hostid, hostuid, and others.
 215  */
 216 struct mtx hostname_mtx;
 217 MTX_SYSINIT(hostname_mtx, &hostname_mtx, "hostname", MTX_DEF);
 218
 219 static int
 220 sysctl_hostname(SYSCTL_HANDLER_ARGS)
 221 {
 222         struct prison *pr;
 223         char tmphostname[MAXHOSTNAMELEN];
 224         int error;
 225
 226         pr = req->td->td_ucred->cr_prison;
 227         if (pr != NULL) {
 228                 if (!jail_set_hostname_allowed && req->newptr)
 229                         return (EPERM);
 230                 /*
 231                  * Process is in jail, so make a local copy of jail
 232                  * hostname to get/set so we don't have to hold the jail
 233                  * mutex during the sysctl copyin/copyout activities.
 234                  */
 235                 mtx_lock(&pr->pr_mtx);
 236                 bcopy(pr->pr_host, tmphostname, MAXHOSTNAMELEN);
 237                 mtx_unlock(&pr->pr_mtx);
 238
 239                 error = sysctl_handle_string(oidp, tmphostname,
 240                     sizeof pr->pr_host, req);
 241
 242                 if (req->newptr != NULL && error == 0) {
 243                         /*
 244                          * Copy the locally set hostname to the jail, if
 245                          * appropriate.
 246                          */
 247                         mtx_lock(&pr->pr_mtx);
 248                         bcopy(tmphostname, pr->pr_host, MAXHOSTNAMELEN);
 249                         mtx_unlock(&pr->pr_mtx);
 250                 }
 251         } else {
 252                 mtx_lock(&hostname_mtx);
 253                 bcopy(V_hostname, tmphostname, MAXHOSTNAMELEN);
 254                 mtx_unlock(&hostname_mtx);
 255                 error = sysctl_handle_string(oidp, tmphostname,
 256                     sizeof tmphostname, req);
 257                 if (req->newptr != NULL && error == 0) {
 258                         mtx_lock(&hostname_mtx);
 259                         bcopy(tmphostname, V_hostname, MAXHOSTNAMELEN);
 260                         mtx_unlock(&hostname_mtx);
 261                 }
 262         }
 263         return (error);
 264 }
 265
 266 SYSCTL_PROC(_kern, KERN_HOSTNAME, hostname,
 267        CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_PRISON,
 268        0, 0, sysctl_hostname, "A", "Hostname");
 269
 270 static int      regression_securelevel_nonmonotonic = 0;
 271
 272 #ifdef REGRESSION
 273 SYSCTL_INT(_regression, OID_AUTO, securelevel_nonmonotonic, CTLFLAG_RW,
 274     &regression_securelevel_nonmonotonic, 0, "securelevel may be lowered");
 275 #endif
 276
 277 int securelevel = -1;
 278 static struct mtx securelevel_mtx;
 279
 280 MTX_SYSINIT(securelevel_lock, &securelevel_mtx, "securelevel mutex lock",
 281     MTX_DEF);
 282
 283 static int
 284 sysctl_kern_securelvl(SYSCTL_HANDLER_ARGS)
 285 {
 286         struct prison *pr;
 287         int error, level;
 288
 289         pr = req->td->td_ucred->cr_prison;
 290
 291         /*
 292          * If the process is in jail, return the maximum of the global and
 293          * local levels; otherwise, return the global level.  Perform a
 294          * lockless read since the securelevel is an integer.
 295          */
 296         if (pr != NULL)
 297                 level = imax(securelevel, pr->pr_securelevel);
 298         else
 299                 level = securelevel;
 300         error = sysctl_handle_int(oidp, &level, 0, req);
 301         if (error || !req->newptr)
 302                 return (error);
 303         /*
 304          * Permit update only if the new securelevel exceeds the
 305          * global level, and local level if any.
 306          */
 307         if (pr != NULL) {
 308                 mtx_lock(&pr->pr_mtx);
 309                 if (!regression_securelevel_nonmonotonic &&
 310                     (level < imax(securelevel, pr->pr_securelevel))) {
 311                         mtx_unlock(&pr->pr_mtx);
 312                         return (EPERM);
 313                 }
 314                 pr->pr_securelevel = level;
 315                 mtx_unlock(&pr->pr_mtx);
 316         } else {
 317                 mtx_lock(&securelevel_mtx);
 318                 if (!regression_securelevel_nonmonotonic &&
 319                     (level < securelevel)) {
 320                         mtx_unlock(&securelevel_mtx);
 321                         return (EPERM);
 322                 }
 323                 securelevel = level;
 324                 mtx_unlock(&securelevel_mtx);
 325         }
 326         return (error);
 327 }
 328
 329 SYSCTL_PROC(_kern, KERN_SECURELVL, securelevel,
 330     CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, sysctl_kern_securelvl,
 331     "I", "Current secure level");
 332
 333 #ifdef INCLUDE_CONFIG_FILE
 334 /* Actual kernel configuration options. */
 335 extern char kernconfstring[];
 336
 337 static int
 338 sysctl_kern_config(SYSCTL_HANDLER_ARGS)
 339 {
 340         return (sysctl_handle_string(oidp, kernconfstring,
 341             strlen(kernconfstring), req));
 342 }
 343
 344 SYSCTL_PROC(_kern, OID_AUTO, conftxt, CTLTYPE_STRING|CTLFLAG_RW,
 345     0, 0, sysctl_kern_config, "", "Kernel configuration file");
 346 #endif
 347
 348 char domainname[MAXHOSTNAMELEN];        /* Protected by hostname_mtx. */
 349
 350 static int
 351 sysctl_domainname(SYSCTL_HANDLER_ARGS)
 352 {
 353         char tmpdomainname[MAXHOSTNAMELEN];
 354         int error;
 355
 356         mtx_lock(&hostname_mtx);
 357         bcopy(domainname, tmpdomainname, MAXHOSTNAMELEN);
 358         mtx_unlock(&hostname_mtx);
 359         error = sysctl_handle_string(oidp, tmpdomainname,
 360             sizeof tmpdomainname, req);
 361         if (req->newptr != NULL && error == 0) {
 362                 mtx_lock(&hostname_mtx);
 363                 bcopy(tmpdomainname, domainname, MAXHOSTNAMELEN);
 364                 mtx_unlock(&hostname_mtx);
 365         }
 366         return (error);
 367 }
 368
 369 SYSCTL_PROC(_kern, KERN_NISDOMAINNAME, domainname, CTLTYPE_STRING|CTLFLAG_RW,
 370        0, 0, sysctl_domainname, "A", "Name of the current YP/NIS domain");
 371
 372 u_long hostid;
 373 SYSCTL_ULONG(_kern, KERN_HOSTID, hostid, CTLFLAG_RW, &hostid, 0, "Host ID");
 374 char hostuuid[64] = "00000000-0000-0000-0000-000000000000";
 375 SYSCTL_STRING(_kern, KERN_HOSTUUID, hostuuid, CTLFLAG_RW, hostuuid,
 376     sizeof(hostuuid), "Host UUID");
 377
 378 SYSCTL_NODE(_kern, OID_AUTO, features, CTLFLAG_RD, 0, "Kernel Features");
 379
 380 #ifdef COMPAT_FREEBSD4
 381 FEATURE(compat_freebsd4, "Compatible with FreeBSD 4");
 382 #endif
 383
 384 #ifdef COMPAT_FREEBSD5
 385 FEATURE(compat_freebsd5, "Compatible with FreeBSD 5");
 386 #endif
 387
 388 #ifdef COMPAT_FREEBSD6
 389 FEATURE(compat_freebsd6, "Compatible with FreeBSD 6");
 390 #endif
 391
 392 #ifdef COMPAT_FREEBSD7
 393 FEATURE(compat_freebsd7, "Compatible with FreeBSD 7");
 394 #endif
 395
 396 /*
 397  * This is really cheating.  These actually live in the libc, something
 398  * which I'm not quite sure is a good idea anyway, but in order for
 399  * getnext and friends to actually work, we define dummies here.
 400  */
 401 SYSCTL_STRING(_user, USER_CS_PATH, cs_path, CTLFLAG_RD,
 402     "", 0, "PATH that finds all the standard utilities");
 403 SYSCTL_INT(_user, USER_BC_BASE_MAX, bc_base_max, CTLFLAG_RD,
 404     0, 0, "Max ibase/obase values in bc(1)");
 405 SYSCTL_INT(_user, USER_BC_DIM_MAX, bc_dim_max, CTLFLAG_RD,
 406     0, 0, "Max array size in bc(1)");
 407 SYSCTL_INT(_user, USER_BC_SCALE_MAX, bc_scale_max, CTLFLAG_RD,
 408     0, 0, "Max scale value in bc(1)");
 409 SYSCTL_INT(_user, USER_BC_STRING_MAX, bc_string_max, CTLFLAG_RD,
 410     0, 0, "Max string length in bc(1)");
 411 SYSCTL_INT(_user, USER_COLL_WEIGHTS_MAX, coll_weights_max, CTLFLAG_RD,
 412     0, 0, "Maximum number of weights assigned to an LC_COLLATE locale entry");
 413 SYSCTL_INT(_user, USER_EXPR_NEST_MAX, expr_nest_max, CTLFLAG_RD, 0, 0, "");
 414 SYSCTL_INT(_user, USER_LINE_MAX, line_max, CTLFLAG_RD,
 415     0, 0, "Max length (bytes) of a text-processing utility's input line");
 416 SYSCTL_INT(_user, USER_RE_DUP_MAX, re_dup_max, CTLFLAG_RD,
 417     0, 0, "Maximum number of repeats of a regexp permitted");
 418 SYSCTL_INT(_user, USER_POSIX2_VERSION, posix2_version, CTLFLAG_RD,
 419     0, 0,
 420     "The version of POSIX 1003.2 with which the system attempts to comply");
 421 SYSCTL_INT(_user, USER_POSIX2_C_BIND, posix2_c_bind, CTLFLAG_RD,
 422     0, 0, "Whether C development supports the C bindings option");
 423 SYSCTL_INT(_user, USER_POSIX2_C_DEV, posix2_c_dev, CTLFLAG_RD,
 424     0, 0, "Whether system supports the C development utilities option");
 425 SYSCTL_INT(_user, USER_POSIX2_CHAR_TERM, posix2_char_term, CTLFLAG_RD,
 426     0, 0, "");
 427 SYSCTL_INT(_user, USER_POSIX2_FORT_DEV, posix2_fort_dev, CTLFLAG_RD,
 428     0, 0, "Whether system supports FORTRAN development utilities");
 429 SYSCTL_INT(_user, USER_POSIX2_FORT_RUN, posix2_fort_run, CTLFLAG_RD,
 430     0, 0, "Whether system supports FORTRAN runtime utilities");
 431 SYSCTL_INT(_user, USER_POSIX2_LOCALEDEF, posix2_localedef, CTLFLAG_RD,
 432     0, 0, "Whether system supports creation of locales");
 433 SYSCTL_INT(_user, USER_POSIX2_SW_DEV, posix2_sw_dev, CTLFLAG_RD,
 434     0, 0, "Whether system supports software development utilities");
 435 SYSCTL_INT(_user, USER_POSIX2_UPE, posix2_upe, CTLFLAG_RD,
 436     0, 0, "Whether system supports the user portability utilities");
 437 SYSCTL_INT(_user, USER_STREAM_MAX, stream_max, CTLFLAG_RD,
 438     0, 0, "Min Maximum number of streams a process may have open at one time");
 439 SYSCTL_INT(_user, USER_TZNAME_MAX, tzname_max, CTLFLAG_RD,
 440     0, 0, "Min Maximum number of types supported for timezone names");
 441
 442 #include <sys/vnode.h>
 443 SYSCTL_INT(_debug_sizeof, OID_AUTO, vnode, CTLFLAG_RD,
 444     0, sizeof(struct vnode), "sizeof(struct vnode)");
 445
 446 SYSCTL_INT(_debug_sizeof, OID_AUTO, proc, CTLFLAG_RD,
 447     0, sizeof(struct proc), "sizeof(struct proc)");
 448
 449 #include <sys/bio.h>
 450 #include <sys/buf.h>
 451 SYSCTL_INT(_debug_sizeof, OID_AUTO, bio, CTLFLAG_RD,
 452     0, sizeof(struct bio), "sizeof(struct bio)");
 453 SYSCTL_INT(_debug_sizeof, OID_AUTO, buf, CTLFLAG_RD,
 454     0, sizeof(struct buf), "sizeof(struct buf)");
 455
 456 #include <sys/user.h>
 457 SYSCTL_INT(_debug_sizeof, OID_AUTO, kinfo_proc, CTLFLAG_RD,
 458     0, sizeof(struct kinfo_proc), "sizeof(struct kinfo_proc)");
 459
 460 /* XXX compatibility, remove for 6.0 */
 461 #include <sys/imgact.h>
 462 #include <sys/imgact_elf.h>
 463 SYSCTL_INT(_kern, OID_AUTO, fallback_elf_brand, CTLFLAG_RW,
 464     &__elfN(fallback_brand), sizeof(__elfN(fallback_brand)),
 465     "compatibility for kern.fallback_elf_brand");