1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 /* 29 * Common name validation routines for ZFS. These routines are shared by the 30 * userland code as well as the ioctl() layer to ensure that we don't 31 * inadvertently expose a hole through direct ioctl()s that never gets tested. 32 * In userland, however, we want significantly more information about _why_ the 33 * name is invalid. In the kernel, we only care whether it's valid or not. 34 * Each routine therefore takes a 'namecheck_err_t' which describes exactly why 35 * the name failed to validate. 36 * 37 * Each function returns 0 on success, -1 on error. 38 */ 39 40 #if defined(_KERNEL) 41 #include <sys/systm.h> 42 #else 43 #include <string.h> 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/nvpair.h> 48 #include "zfs_namecheck.h" 49 #include "zfs_deleg.h" 50 51 static int 52 valid_char(char c) 53 { 54 return ((c >= 'a' && c <= 'z') || 55 (c >= 'A' && c <= 'Z') || 56 (c >= '0' && c <= '9') || 57 c == '-' || c == '_' || c == '.' || c == ':'); 58 } 59 60 /* 61 * Snapshot names must be made up of alphanumeric characters plus the following 62 * characters: 63 * 64 * [-_.:] 65 */ 66 int 67 snapshot_namecheck(const char *path, namecheck_err_t *why, char *what) 68 { 69 const char *loc; 70 71 if (strlen(path) >= MAXNAMELEN) { 72 if (why) 73 *why = NAME_ERR_TOOLONG; 74 return (-1); 75 } 76 77 if (path[0] == '\0') { 78 if (why) 79 *why = NAME_ERR_EMPTY_COMPONENT; 80 return (-1); 81 } 82 83 for (loc = path; *loc; loc++) { 84 if (!valid_char(*loc)) { 85 if (why) { 86 *why = NAME_ERR_INVALCHAR; 87 *what = *loc; 88 } 89 return (-1); 90 } 91 } 92 return (0); 93 } 94 95 96 /* 97 * Permissions set name must start with the letter '@' followed by the 98 * same character restrictions as snapshot names, except that the name 99 * cannot exceed 64 characters. 100 */ 101 int 102 permset_namecheck(const char *path, namecheck_err_t *why, char *what) 103 { 104 if (strlen(path) >= ZFS_PERMSET_MAXLEN) { 105 if (why) 106 *why = NAME_ERR_TOOLONG; 107 return (-1); 108 } 109 110 if (path[0] != '@') { 111 if (why) { 112 *why = NAME_ERR_NO_AT; 113 *what = path[0]; 114 } 115 return (-1); 116 } 117 118 return (snapshot_namecheck(&path[1], why, what)); 119 } 120 121 /* 122 * Dataset names must be of the following form: 123 * 124 * [component][/]*[component][@component] 125 * 126 * Where each component is made up of alphanumeric characters plus the following 127 * characters: 128 * 129 * [-_.:%] 130 * 131 * We allow '%' here as we use that character internally to create unique 132 * names for temporary clones (for online recv). 133 */ 134 int 135 dataset_namecheck(const char *path, namecheck_err_t *why, char *what) 136 { 137 const char *loc, *end; 138 int found_snapshot; 139 140 /* 141 * Make sure the name is not too long. 142 * 143 * ZFS_MAXNAMELEN is the maximum dataset length used in the userland 144 * which is the same as MAXNAMELEN used in the kernel. 145 * If ZFS_MAXNAMELEN value is changed, make sure to cleanup all 146 * places using MAXNAMELEN. 147 */ 148 149 if (strlen(path) >= MAXNAMELEN) { 150 if (why) 151 *why = NAME_ERR_TOOLONG; 152 return (-1); 153 } 154 155 /* Explicitly check for a leading slash. */ 156 if (path[0] == '/') { 157 if (why) 158 *why = NAME_ERR_LEADING_SLASH; 159 return (-1); 160 } 161 162 if (path[0] == '\0') { 163 if (why) 164 *why = NAME_ERR_EMPTY_COMPONENT; 165 return (-1); 166 } 167 168 loc = path; 169 found_snapshot = 0; 170 for (;;) { 171 /* Find the end of this component */ 172 end = loc; 173 while (*end != '/' && *end != '@' && *end != '\0') 174 end++; 175 176 if (*end == '\0' && end[-1] == '/') { 177 /* trailing slashes are not allowed */ 178 if (why) 179 *why = NAME_ERR_TRAILING_SLASH; 180 return (-1); 181 } 182 183 /* Zero-length components are not allowed */ 184 if (loc == end) { 185 if (why) { 186 /* 187 * Make sure this is really a zero-length 188 * component and not a '@@'. 189 */ 190 if (*end == '@' && found_snapshot) { 191 *why = NAME_ERR_MULTIPLE_AT; 192 } else { 193 *why = NAME_ERR_EMPTY_COMPONENT; 194 } 195 } 196 197 return (-1); 198 } 199 200 /* Validate the contents of this component */ 201 while (loc != end) { 202 if (!valid_char(*loc) && *loc != '%') { 203 if (why) { 204 *why = NAME_ERR_INVALCHAR; 205 *what = *loc; 206 } 207 return (-1); 208 } 209 loc++; 210 } 211 212 /* If we've reached the end of the string, we're OK */ 213 if (*end == '\0') 214 return (0); 215 216 if (*end == '@') { 217 /* 218 * If we've found an @ symbol, indicate that we're in 219 * the snapshot component, and report a second '@' 220 * character as an error. 221 */ 222 if (found_snapshot) { 223 if (why) 224 *why = NAME_ERR_MULTIPLE_AT; 225 return (-1); 226 } 227 228 found_snapshot = 1; 229 } 230 231 /* 232 * If there is a '/' in a snapshot name 233 * then report an error 234 */ 235 if (*end == '/' && found_snapshot) { 236 if (why) 237 *why = NAME_ERR_TRAILING_SLASH; 238 return (-1); 239 } 240 241 /* Update to the next component */ 242 loc = end + 1; 243 } 244 } 245 246 247 /* 248 * mountpoint names must be of the following form: 249 * 250 * /[component][/]*[component][/] 251 */ 252 int 253 mountpoint_namecheck(const char *path, namecheck_err_t *why) 254 { 255 const char *start, *end; 256 257 /* 258 * Make sure none of the mountpoint component names are too long. 259 * If a component name is too long then the mkdir of the mountpoint 260 * will fail but then the mountpoint property will be set to a value 261 * that can never be mounted. Better to fail before setting the prop. 262 * Extra slashes are OK, they will be tossed by the mountpoint mkdir. 263 */ 264 265 if (path == NULL || *path != '/') { 266 if (why) 267 *why = NAME_ERR_LEADING_SLASH; 268 return (-1); 269 } 270 271 /* Skip leading slash */ 272 start = &path[1]; 273 do { 274 end = start; 275 while (*end != '/' && *end != '\0') 276 end++; 277 278 if (end - start >= MAXNAMELEN) { 279 if (why) 280 *why = NAME_ERR_TOOLONG; 281 return (-1); 282 } 283 start = end + 1; 284 285 } while (*end != '\0'); 286 287 return (0); 288 } 289 290 /* 291 * For pool names, we have the same set of valid characters as described in 292 * dataset names, with the additional restriction that the pool name must begin 293 * with a letter. The pool names 'raidz' and 'mirror' are also reserved names 294 * that cannot be used. 295 */ 296 int 297 pool_namecheck(const char *pool, namecheck_err_t *why, char *what) 298 { 299 const char *c; 300 301 /* 302 * Make sure the name is not too long. 303 * 304 * ZPOOL_MAXNAMELEN is the maximum pool length used in the userland 305 * which is the same as MAXNAMELEN used in the kernel. 306 * If ZPOOL_MAXNAMELEN value is changed, make sure to cleanup all 307 * places using MAXNAMELEN. 308 */ 309 if (strlen(pool) >= MAXNAMELEN) { 310 if (why) 311 *why = NAME_ERR_TOOLONG; 312 return (-1); 313 } 314 315 c = pool; 316 while (*c != '\0') { 317 if (!valid_char(*c)) { 318 if (why) { 319 *why = NAME_ERR_INVALCHAR; 320 *what = *c; 321 } 322 return (-1); 323 } 324 c++; 325 } 326 327 if (!(*pool >= 'a' && *pool <= 'z') && 328 !(*pool >= 'A' && *pool <= 'Z')) { 329 if (why) 330 *why = NAME_ERR_NOLETTER; 331 return (-1); 332 } 333 334 if (strcmp(pool, "mirror") == 0 || strcmp(pool, "raidz") == 0) { 335 if (why) 336 *why = NAME_ERR_RESERVED; 337 return (-1); 338 } 339 340 if (pool[0] == 'c' && (pool[1] >= '0' && pool[1] <= '9')) { 341 if (why) 342 *why = NAME_ERR_DISKLIKE; 343 return (-1); 344 } 345 346 return (0); 347 } 348 349 /* 350 * Check if the dataset name is private for internal usage. 351 * '$' is reserved for internal dataset names. e.g. "$MOS" 352 * 353 * Return 1 if the given name is used internally. 354 * Return 0 if it is not. 355 */ 356 int 357 dataset_name_hidden(const char *name) 358 { 359 if (strchr(name, '$') != NULL) 360 return (1); 361 362 return (0); 363 } 364