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/sx.h> 56 #include <sys/unistd.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|CTLFLAG_MPSAFE, 91 kern_ident, 0, "Kernel identifier"); 92 93 SYSCTL_STRING(_kern, KERN_OSRELEASE, osrelease, CTLFLAG_RD|CTLFLAG_MPSAFE, 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|CTLFLAG_MPSAFE, 100 version, 0, "Kernel version"); 101 102 SYSCTL_STRING(_kern, KERN_OSTYPE, ostype, CTLFLAG_RD|CTLFLAG_MPSAFE, 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, 169 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 170 sysctl_kern_arnd, "", "arc4rand"); 171 172 static int 173 sysctl_hw_physmem(SYSCTL_HANDLER_ARGS) 174 { 175 u_long val; 176 177 val = ctob(physmem); 178 return (sysctl_handle_long(oidp, &val, 0, req)); 179 } 180 181 SYSCTL_PROC(_hw, HW_PHYSMEM, physmem, CTLTYPE_ULONG | CTLFLAG_RD, 182 0, 0, sysctl_hw_physmem, "LU", ""); 183 184 static int 185 sysctl_hw_realmem(SYSCTL_HANDLER_ARGS) 186 { 187 u_long val; 188 val = ctob(realmem); 189 return (sysctl_handle_long(oidp, &val, 0, req)); 190 } 191 SYSCTL_PROC(_hw, HW_REALMEM, realmem, CTLTYPE_ULONG | CTLFLAG_RD, 192 0, 0, sysctl_hw_realmem, "LU", ""); 193 static int 194 sysctl_hw_usermem(SYSCTL_HANDLER_ARGS) 195 { 196 u_long val; 197 198 val = ctob(physmem - cnt.v_wire_count); 199 return (sysctl_handle_long(oidp, &val, 0, req)); 200 } 201 202 SYSCTL_PROC(_hw, HW_USERMEM, usermem, CTLTYPE_ULONG | CTLFLAG_RD, 203 0, 0, sysctl_hw_usermem, "LU", ""); 204 205 SYSCTL_ULONG(_hw, OID_AUTO, availpages, CTLFLAG_RD, &physmem, 0, ""); 206 207 static char machine_arch[] = MACHINE_ARCH; 208 SYSCTL_STRING(_hw, HW_MACHINE_ARCH, machine_arch, CTLFLAG_RD, 209 machine_arch, 0, "System architecture"); 210 211 static int 212 sysctl_hostname(SYSCTL_HANDLER_ARGS) 213 { 214 struct prison *pr, *cpr; 215 size_t pr_offset; 216 char tmpname[MAXHOSTNAMELEN]; 217 int descend, error, len; 218 219 /* 220 * This function can set: hostname domainname hostuuid. 221 * Keep that in mind when comments say "hostname". 222 */ 223 pr_offset = (size_t)arg1; 224 len = arg2; 225 KASSERT(len <= sizeof(tmpname), 226 ("length %d too long for %s", len, __func__)); 227 228 pr = req->td->td_ucred->cr_prison; 229 if (!(pr->pr_allow & PR_ALLOW_SET_HOSTNAME) && req->newptr) 230 return (EPERM); 231 /* 232 * Make a local copy of hostname to get/set so we don't have to hold 233 * the jail mutex during the sysctl copyin/copyout activities. 234 */ 235 mtx_lock(&pr->pr_mtx); 236 bcopy((char *)pr + pr_offset, tmpname, len); 237 mtx_unlock(&pr->pr_mtx); 238 239 error = sysctl_handle_string(oidp, tmpname, len, req); 240 241 if (req->newptr != NULL && error == 0) { 242 /* 243 * Copy the locally set hostname to all jails that share 244 * this host info. 245 */ 246 sx_slock(&allprison_lock); 247 while (!(pr->pr_flags & PR_HOST)) 248 pr = pr->pr_parent; 249 mtx_lock(&pr->pr_mtx); 250 bcopy(tmpname, (char *)pr + pr_offset, len); 251 FOREACH_PRISON_DESCENDANT_LOCKED(pr, cpr, descend) 252 if (cpr->pr_flags & PR_HOST) 253 descend = 0; 254 else 255 bcopy(tmpname, (char *)cpr + pr_offset, len); 256 mtx_unlock(&pr->pr_mtx); 257 sx_sunlock(&allprison_lock); 258 } 259 return (error); 260 } 261 262 SYSCTL_PROC(_kern, KERN_HOSTNAME, hostname, 263 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE, 264 (void *)(offsetof(struct prison, pr_hostname)), MAXHOSTNAMELEN, 265 sysctl_hostname, "A", "Hostname"); 266 SYSCTL_PROC(_kern, KERN_NISDOMAINNAME, domainname, 267 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE, 268 (void *)(offsetof(struct prison, pr_domainname)), MAXHOSTNAMELEN, 269 sysctl_hostname, "A", "Name of the current YP/NIS domain"); 270 SYSCTL_PROC(_kern, KERN_HOSTUUID, hostuuid, 271 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE, 272 (void *)(offsetof(struct prison, pr_hostuuid)), HOSTUUIDLEN, 273 sysctl_hostname, "A", "Host UUID"); 274 275 static int regression_securelevel_nonmonotonic = 0; 276 277 #ifdef REGRESSION 278 SYSCTL_INT(_regression, OID_AUTO, securelevel_nonmonotonic, CTLFLAG_RW, 279 ®ression_securelevel_nonmonotonic, 0, "securelevel may be lowered"); 280 #endif 281 282 static int 283 sysctl_kern_securelvl(SYSCTL_HANDLER_ARGS) 284 { 285 struct prison *pr, *cpr; 286 int descend, error, level; 287 288 pr = req->td->td_ucred->cr_prison; 289 290 /* 291 * Reading the securelevel is easy, since the current jail's level 292 * is known to be at least as secure as any higher levels. Perform 293 * a lockless read since the securelevel is an integer. 294 */ 295 level = pr->pr_securelevel; 296 error = sysctl_handle_int(oidp, &level, 0, req); 297 if (error || !req->newptr) 298 return (error); 299 /* Permit update only if the new securelevel exceeds the old. */ 300 sx_slock(&allprison_lock); 301 mtx_lock(&pr->pr_mtx); 302 if (!regression_securelevel_nonmonotonic && 303 level < pr->pr_securelevel) { 304 mtx_unlock(&pr->pr_mtx); 305 sx_sunlock(&allprison_lock); 306 return (EPERM); 307 } 308 pr->pr_securelevel = level; 309 /* 310 * Set all child jails to be at least this level, but do not lower 311 * them (even if regression_securelevel_nonmonotonic). 312 */ 313 FOREACH_PRISON_DESCENDANT_LOCKED(pr, cpr, descend) { 314 if (cpr->pr_securelevel < level) 315 cpr->pr_securelevel = level; 316 } 317 mtx_unlock(&pr->pr_mtx); 318 sx_sunlock(&allprison_lock); 319 return (error); 320 } 321 322 SYSCTL_PROC(_kern, KERN_SECURELVL, securelevel, 323 CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, sysctl_kern_securelvl, 324 "I", "Current secure level"); 325 326 #ifdef INCLUDE_CONFIG_FILE 327 /* Actual kernel configuration options. */ 328 extern char kernconfstring[]; 329 330 static int 331 sysctl_kern_config(SYSCTL_HANDLER_ARGS) 332 { 333 return (sysctl_handle_string(oidp, kernconfstring, 334 strlen(kernconfstring), req)); 335 } 336 337 SYSCTL_PROC(_kern, OID_AUTO, conftxt, CTLTYPE_STRING|CTLFLAG_RW, 338 0, 0, sysctl_kern_config, "", "Kernel configuration file"); 339 #endif 340 341 static int 342 sysctl_hostid(SYSCTL_HANDLER_ARGS) 343 { 344 struct prison *pr, *cpr; 345 u_long tmpid; 346 int descend, error; 347 348 /* 349 * Like sysctl_hostname, except it operates on a u_long 350 * instead of a string, and is used only for hostid. 351 */ 352 pr = req->td->td_ucred->cr_prison; 353 if (!(pr->pr_allow & PR_ALLOW_SET_HOSTNAME) && req->newptr) 354 return (EPERM); 355 tmpid = pr->pr_hostid; 356 error = sysctl_handle_long(oidp, &tmpid, 0, req); 357 358 if (req->newptr != NULL && error == 0) { 359 sx_slock(&allprison_lock); 360 while (!(pr->pr_flags & PR_HOST)) 361 pr = pr->pr_parent; 362 mtx_lock(&pr->pr_mtx); 363 pr->pr_hostid = tmpid; 364 FOREACH_PRISON_DESCENDANT_LOCKED(pr, cpr, descend) 365 if (cpr->pr_flags & PR_HOST) 366 descend = 0; 367 else 368 cpr->pr_hostid = tmpid; 369 mtx_unlock(&pr->pr_mtx); 370 sx_sunlock(&allprison_lock); 371 } 372 return (error); 373 } 374 375 SYSCTL_PROC(_kern, KERN_HOSTID, hostid, 376 CTLTYPE_ULONG | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE, 377 NULL, 0, sysctl_hostid, "LU", "Host ID"); 378 379 SYSCTL_NODE(_kern, OID_AUTO, features, CTLFLAG_RD, 0, "Kernel Features"); 380 381 #ifdef COMPAT_FREEBSD4 382 FEATURE(compat_freebsd4, "Compatible with FreeBSD 4"); 383 #endif 384 385 #ifdef COMPAT_FREEBSD5 386 FEATURE(compat_freebsd5, "Compatible with FreeBSD 5"); 387 #endif 388 389 #ifdef COMPAT_FREEBSD6 390 FEATURE(compat_freebsd6, "Compatible with FreeBSD 6"); 391 #endif 392 393 #ifdef COMPAT_FREEBSD7 394 FEATURE(compat_freebsd7, "Compatible with FreeBSD 7"); 395 #endif 396 397 /* 398 * This is really cheating. These actually live in the libc, something 399 * which I'm not quite sure is a good idea anyway, but in order for 400 * getnext and friends to actually work, we define dummies here. 401 */ 402 SYSCTL_STRING(_user, USER_CS_PATH, cs_path, CTLFLAG_RD, 403 "", 0, "PATH that finds all the standard utilities"); 404 SYSCTL_INT(_user, USER_BC_BASE_MAX, bc_base_max, CTLFLAG_RD, 405 0, 0, "Max ibase/obase values in bc(1)"); 406 SYSCTL_INT(_user, USER_BC_DIM_MAX, bc_dim_max, CTLFLAG_RD, 407 0, 0, "Max array size in bc(1)"); 408 SYSCTL_INT(_user, USER_BC_SCALE_MAX, bc_scale_max, CTLFLAG_RD, 409 0, 0, "Max scale value in bc(1)"); 410 SYSCTL_INT(_user, USER_BC_STRING_MAX, bc_string_max, CTLFLAG_RD, 411 0, 0, "Max string length in bc(1)"); 412 SYSCTL_INT(_user, USER_COLL_WEIGHTS_MAX, coll_weights_max, CTLFLAG_RD, 413 0, 0, "Maximum number of weights assigned to an LC_COLLATE locale entry"); 414 SYSCTL_INT(_user, USER_EXPR_NEST_MAX, expr_nest_max, CTLFLAG_RD, 0, 0, ""); 415 SYSCTL_INT(_user, USER_LINE_MAX, line_max, CTLFLAG_RD, 416 0, 0, "Max length (bytes) of a text-processing utility's input line"); 417 SYSCTL_INT(_user, USER_RE_DUP_MAX, re_dup_max, CTLFLAG_RD, 418 0, 0, "Maximum number of repeats of a regexp permitted"); 419 SYSCTL_INT(_user, USER_POSIX2_VERSION, posix2_version, CTLFLAG_RD, 420 0, 0, 421 "The version of POSIX 1003.2 with which the system attempts to comply"); 422 SYSCTL_INT(_user, USER_POSIX2_C_BIND, posix2_c_bind, CTLFLAG_RD, 423 0, 0, "Whether C development supports the C bindings option"); 424 SYSCTL_INT(_user, USER_POSIX2_C_DEV, posix2_c_dev, CTLFLAG_RD, 425 0, 0, "Whether system supports the C development utilities option"); 426 SYSCTL_INT(_user, USER_POSIX2_CHAR_TERM, posix2_char_term, CTLFLAG_RD, 427 0, 0, ""); 428 SYSCTL_INT(_user, USER_POSIX2_FORT_DEV, posix2_fort_dev, CTLFLAG_RD, 429 0, 0, "Whether system supports FORTRAN development utilities"); 430 SYSCTL_INT(_user, USER_POSIX2_FORT_RUN, posix2_fort_run, CTLFLAG_RD, 431 0, 0, "Whether system supports FORTRAN runtime utilities"); 432 SYSCTL_INT(_user, USER_POSIX2_LOCALEDEF, posix2_localedef, CTLFLAG_RD, 433 0, 0, "Whether system supports creation of locales"); 434 SYSCTL_INT(_user, USER_POSIX2_SW_DEV, posix2_sw_dev, CTLFLAG_RD, 435 0, 0, "Whether system supports software development utilities"); 436 SYSCTL_INT(_user, USER_POSIX2_UPE, posix2_upe, CTLFLAG_RD, 437 0, 0, "Whether system supports the user portability utilities"); 438 SYSCTL_INT(_user, USER_STREAM_MAX, stream_max, CTLFLAG_RD, 439 0, 0, "Min Maximum number of streams a process may have open at one time"); 440 SYSCTL_INT(_user, USER_TZNAME_MAX, tzname_max, CTLFLAG_RD, 441 0, 0, "Min Maximum number of types supported for timezone names"); 442 443 #include <sys/vnode.h> 444 SYSCTL_INT(_debug_sizeof, OID_AUTO, vnode, CTLFLAG_RD, 445 0, sizeof(struct vnode), "sizeof(struct vnode)"); 446 447 SYSCTL_INT(_debug_sizeof, OID_AUTO, proc, CTLFLAG_RD, 448 0, sizeof(struct proc), "sizeof(struct proc)"); 449 450 #include <sys/bio.h> 451 #include <sys/buf.h> 452 SYSCTL_INT(_debug_sizeof, OID_AUTO, bio, CTLFLAG_RD, 453 0, sizeof(struct bio), "sizeof(struct bio)"); 454 SYSCTL_INT(_debug_sizeof, OID_AUTO, buf, CTLFLAG_RD, 455 0, sizeof(struct buf), "sizeof(struct buf)"); 456 457 #include <sys/user.h> 458 SYSCTL_INT(_debug_sizeof, OID_AUTO, kinfo_proc, CTLFLAG_RD, 459 0, sizeof(struct kinfo_proc), "sizeof(struct kinfo_proc)"); 460 461 /* XXX compatibility, remove for 6.0 */ 462 #include <sys/imgact.h> 463 #include <sys/imgact_elf.h> 464 SYSCTL_INT(_kern, OID_AUTO, fallback_elf_brand, CTLFLAG_RW, 465 &__elfN(fallback_brand), sizeof(__elfN(fallback_brand)), 466 "compatibility for kern.fallback_elf_brand"); 467