1 /* $NetBSD: sysctl.c,v 1.35 2015/02/05 16:05:20 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char sccsid[] = "@(#)sysctl.c 8.2 (Berkeley) 1/4/94"; 36 #else 37 __RCSID("$NetBSD: sysctl.c,v 1.35 2015/02/05 16:05:20 christos Exp $"); 38 #endif 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include "namespace.h" 42 #include <sys/param.h> 43 #define __COMPAT_SYSCTL 44 #include <sys/sysctl.h> 45 46 #include <assert.h> 47 #include <errno.h> 48 #include <paths.h> 49 #include <stdio.h> 50 #include <string.h> 51 #include <unistd.h> 52 #include "extern.h" 53 54 #ifdef __weak_alias 55 __weak_alias(sysctl,_sysctl) 56 #endif 57 58 /* 59 * handles requests off the user subtree 60 */ 61 static int user_sysctl(const int *, u_int, void *, size_t *, 62 const void *, size_t); 63 64 /* 65 * copies out individual nodes taking target version into account 66 */ 67 static size_t __cvt_node_out(uint, const struct sysctlnode *, void **, 68 size_t *); 69 70 #include <stdlib.h> 71 72 #if defined(__minix) 73 int __sysctl(const int *name, unsigned int namelen, 74 void *oldp, size_t *oldlenp, 75 const void *newp, size_t newlen) 76 { 77 errno = ENOENT; 78 return -1; 79 } 80 #endif /* defined(__minix) */ 81 82 int 83 sysctl(const int *name, unsigned int namelen, 84 void *oldp, size_t *oldlenp, 85 const void *newp, size_t newlen) 86 { 87 size_t oldlen, savelen; 88 int error; 89 90 if (name[0] != CTL_USER) 91 return (__sysctl(name, namelen, oldp, oldlenp, 92 newp, newlen)); 93 94 oldlen = (oldlenp == NULL) ? 0 : *oldlenp; 95 savelen = oldlen; 96 error = user_sysctl(name + 1, namelen - 1, oldp, &oldlen, newp, newlen); 97 98 if (error != 0) { 99 errno = error; 100 return (-1); 101 } 102 103 if (oldlenp != NULL) { 104 *oldlenp = oldlen; 105 if (oldp != NULL && oldlen > savelen) { 106 errno = ENOMEM; 107 return (-1); 108 } 109 } 110 111 return (0); 112 } 113 114 static int 115 user_sysctl(const int *name, unsigned int namelen, 116 void *oldp, size_t *oldlenp, 117 const void *newp, size_t newlen) 118 { 119 #define _INT(s, n, v, d) { \ 120 .sysctl_flags = CTLFLAG_IMMEDIATE|CTLFLAG_PERMANENT| \ 121 CTLTYPE_INT|SYSCTL_VERSION, \ 122 .sysctl_size = sizeof(int), \ 123 .sysctl_name = (s), \ 124 .sysctl_num = (n), \ 125 .sysctl_un.scu_idata = (v), \ 126 .sysctl_desc = (d), \ 127 } 128 129 /* 130 * the nodes under the "user" node 131 */ 132 static const struct sysctlnode sysctl_usermib[] = { 133 #if defined(lint) 134 /* 135 * lint doesn't like my initializers 136 */ 137 0 138 #else /* !lint */ 139 { 140 .sysctl_flags = SYSCTL_VERSION|CTLFLAG_PERMANENT| 141 CTLTYPE_STRING, 142 .sysctl_size = sizeof(_PATH_STDPATH), 143 .sysctl_name = "cs_path", 144 .sysctl_num = USER_CS_PATH, 145 .sysctl_data = __UNCONST(_PATH_STDPATH), 146 .sysctl_desc = __UNCONST( 147 "A value for the PATH environment variable " 148 "that finds all the standard utilities"), 149 }, 150 _INT("bc_base_max", USER_BC_BASE_MAX, BC_BASE_MAX, 151 "The maximum ibase/obase values in the bc(1) utility"), 152 _INT("bc_dim_max", USER_BC_DIM_MAX, BC_DIM_MAX, 153 "The maximum array size in the bc(1) utility"), 154 _INT("bc_scale_max", USER_BC_SCALE_MAX, BC_SCALE_MAX, 155 "The maximum scale value in the bc(1) utility"), 156 _INT("bc_string_max", USER_BC_STRING_MAX, BC_STRING_MAX, 157 "The maximum string length in the bc(1) utility"), 158 _INT("coll_weights_max", USER_COLL_WEIGHTS_MAX, 159 COLL_WEIGHTS_MAX, "The maximum number of weights that can " 160 "be assigned to any entry of the LC_COLLATE order keyword " 161 "in the locale definition file"), 162 _INT("expr_nest_max", USER_EXPR_NEST_MAX, EXPR_NEST_MAX, 163 "The maximum number of expressions that can be nested " 164 "within parenthesis by the expr(1) utility"), 165 _INT("line_max", USER_LINE_MAX, LINE_MAX, "The maximum length " 166 "in bytes of a text-processing utility's input line"), 167 _INT("re_dup_max", USER_RE_DUP_MAX, RE_DUP_MAX, "The maximum " 168 "number of repeated occurrences of a regular expression " 169 "permitted when using interval notation"), 170 _INT("posix2_version", USER_POSIX2_VERSION, _POSIX2_VERSION, 171 "The version of POSIX 1003.2 with which the system " 172 "attempts to comply"), 173 #ifdef _POSIX2_C_BIND 174 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 1, 175 "Whether the system's C-language development facilities " 176 "support the C-Language Bindings Option"), 177 #else 178 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 0, 179 "Whether the system's C-language development facilities " 180 "support the C-Language Bindings Option"), 181 #endif 182 #ifdef POSIX2_C_DEV 183 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 1, 184 "Whether the system supports the C-Language Development " 185 "Utilities Option"), 186 #else 187 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 0, 188 "Whether the system supports the C-Language Development " 189 "Utilities Option"), 190 #endif 191 #ifdef POSIX2_CHAR_TERM 192 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 1, 193 "Whether the system supports at least one terminal type " 194 "capable of all operations described in POSIX 1003.2"), 195 #else 196 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 0, 197 "Whether the system supports at least one terminal type " 198 "capable of all operations described in POSIX 1003.2"), 199 #endif 200 #ifdef POSIX2_FORT_DEV 201 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 1, 202 "Whether the system supports the FORTRAN Development " 203 "Utilities Option"), 204 #else 205 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 0, 206 "Whether the system supports the FORTRAN Development " 207 "Utilities Option"), 208 #endif 209 #ifdef POSIX2_FORT_RUN 210 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 1, 211 "Whether the system supports the FORTRAN Runtime " 212 "Utilities Option"), 213 #else 214 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 0, 215 "Whether the system supports the FORTRAN Runtime " 216 "Utilities Option"), 217 #endif 218 #ifdef POSIX2_LOCALEDEF 219 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 1, 220 "Whether the system supports the creation of locales"), 221 #else 222 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 0, 223 "Whether the system supports the creation of locales"), 224 #endif 225 #ifdef POSIX2_SW_DEV 226 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 1, 227 "Whether the system supports the Software Development " 228 "Utilities Option"), 229 #else 230 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 0, 231 "Whether the system supports the Software Development " 232 "Utilities Option"), 233 #endif 234 #ifdef POSIX2_UPE 235 _INT("posix2_upe", USER_POSIX2_UPE, 1, 236 "Whether the system supports the User Portability " 237 "Utilities Option"), 238 #else 239 _INT("posix2_upe", USER_POSIX2_UPE, 0, 240 "Whether the system supports the User Portability " 241 "Utilities Option"), 242 #endif 243 _INT("stream_max", USER_STREAM_MAX, FOPEN_MAX, 244 "The minimum maximum number of streams that a process " 245 "may have open at any one time"), 246 _INT("tzname_max", USER_TZNAME_MAX, NAME_MAX, 247 "The minimum maximum number of types supported for the " 248 "name of a timezone"), 249 _INT("atexit_max", USER_ATEXIT_MAX, -1, 250 "The maximum number of functions that may be registered " 251 "with atexit(3)"), 252 #endif /* !lint */ 253 }; 254 #undef _INT 255 256 static const int clen = sizeof(sysctl_usermib) / 257 sizeof(sysctl_usermib[0]); 258 259 const struct sysctlnode *node; 260 int ni; 261 size_t l, sz; 262 263 /* 264 * none of these nodes are writable and they're all terminal (for now) 265 */ 266 if (namelen != 1) 267 return (EINVAL); 268 269 l = *oldlenp; 270 if (name[0] == CTL_QUERY) { 271 uint v; 272 node = newp; 273 if (node == NULL) 274 return (EINVAL); 275 else if (SYSCTL_VERS(node->sysctl_flags) == SYSCTL_VERS_1 && 276 newlen == sizeof(struct sysctlnode)) 277 v = SYSCTL_VERS_1; 278 else 279 return (EINVAL); 280 281 sz = 0; 282 for (ni = 0; ni < clen; ni++) 283 sz += __cvt_node_out(v, &sysctl_usermib[ni], &oldp, &l); 284 *oldlenp = sz; 285 return (0); 286 } 287 288 if (name[0] == CTL_DESCRIBE) { 289 /* 290 * XXX make sure this is larger than the largest 291 * "user" description 292 */ 293 char buf[192]; 294 struct sysctldesc *d1 = (void *)&buf[0], *d2 = oldp; 295 size_t d; 296 297 node = newp; 298 if (node != NULL && 299 (SYSCTL_VERS(node->sysctl_flags) < SYSCTL_VERS_1 || 300 newlen != sizeof(struct sysctlnode))) 301 return (EINVAL); 302 303 sz = 0; 304 for (ni = 0; ni < clen; ni++) { 305 memset(&buf[0], 0, sizeof(buf)); 306 if (node != NULL && 307 node->sysctl_num != sysctl_usermib[ni].sysctl_num) 308 continue; 309 d1->descr_num = sysctl_usermib[ni].sysctl_num; 310 d1->descr_ver = sysctl_usermib[ni].sysctl_ver; 311 if (sysctl_usermib[ni].sysctl_desc == NULL) 312 d1->descr_len = 1; 313 else { 314 size_t dlen; 315 (void)strlcpy(d1->descr_str, 316 sysctl_usermib[ni].sysctl_desc, 317 sizeof(buf) - sizeof(*d1)); 318 dlen = strlen(d1->descr_str) + 1; 319 _DIAGASSERT(__type_fit(uint32_t, dlen)); 320 d1->descr_len = (uint32_t)dlen; 321 } 322 d = (size_t)__sysc_desc_adv(NULL, d1->descr_len); 323 if (d2 != NULL) 324 memcpy(d2, d1, d); 325 sz += d; 326 d2 = (struct sysctldesc *)(void *)((char *)d2 + d); 327 if (node != NULL) 328 break; 329 } 330 *oldlenp = sz; 331 if (sz == 0 && node != NULL) 332 return (ENOENT); 333 return (0); 334 335 } 336 337 /* 338 * none of these nodes are writable 339 */ 340 if (newp != NULL || newlen != 0) 341 return (EPERM); 342 343 node = &sysctl_usermib[0]; 344 for (ni = 0; ni < clen; ni++) 345 if (name[0] == node[ni].sysctl_num) 346 break; 347 if (ni == clen) 348 return (EOPNOTSUPP); 349 350 node = &node[ni]; 351 if (node->sysctl_flags & CTLFLAG_IMMEDIATE) { 352 switch (SYSCTL_TYPE(node->sysctl_flags)) { 353 case CTLTYPE_INT: 354 newp = &node->sysctl_idata; 355 break; 356 case CTLTYPE_QUAD: 357 newp = &node->sysctl_qdata; 358 break; 359 default: 360 return (EINVAL); 361 } 362 } 363 else 364 newp = node->sysctl_data; 365 366 l = MIN(l, node->sysctl_size); 367 if (oldp != NULL) 368 memcpy(oldp, newp, l); 369 *oldlenp = node->sysctl_size; 370 371 return (0); 372 } 373 374 static size_t 375 __cvt_node_out(uint v, const struct sysctlnode *n, void **o, size_t *l) 376 { 377 const void *src = n; 378 size_t sz; 379 380 switch (v) { 381 #if (SYSCTL_VERSION != SYSCTL_VERS_1) 382 #error __cvt_node_out: no support for SYSCTL_VERSION 383 #endif /* (SYSCTL_VERSION != SYSCTL_VERS_1) */ 384 385 case SYSCTL_VERSION: 386 sz = sizeof(struct sysctlnode); 387 break; 388 389 default: 390 sz = 0; 391 break; 392 } 393 394 if (sz > 0 && *o != NULL && *l >= sz) { 395 memcpy(*o, src, sz); 396 *o = sz + (caddr_t)*o; 397 *l -= sz; 398 } 399 400 return(sz); 401 } 402