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 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* 27 * Common name validation routines for ZFS. These routines are shared by the 28 * userland code as well as the ioctl() layer to ensure that we don't 29 * inadvertently expose a hole through direct ioctl()s that never gets tested. 30 * In userland, however, we want significantly more information about _why_ the 31 * name is invalid. In the kernel, we only care whether it's valid or not. 32 * Each routine therefore takes a 'namecheck_err_t' which describes exactly why 33 * the name failed to validate. 34 * 35 * Each function returns 0 on success, -1 on error. 36 */ 37 38 #if defined(_KERNEL) 39 #include <sys/systm.h> 40 #else 41 #include <string.h> 42 #endif 43 44 #include <sys/param.h> 45 #include <sys/nvpair.h> 46 #include "zfs_namecheck.h" 47 #include "zfs_deleg.h" 48 49 static int 50 valid_char(char c) 51 { 52 return ((c >= 'a' && c <= 'z') || 53 (c >= 'A' && c <= 'Z') || 54 (c >= '0' && c <= '9') || 55 c == '-' || c == '_' || c == '.' || c == ':' || c == ' '); 56 } 57 58 /* 59 * Snapshot names must be made up of alphanumeric characters plus the following 60 * characters: 61 * 62 * [-_.: ] 63 */ 64 int 65 snapshot_namecheck(const char *path, namecheck_err_t *why, char *what) 66 { 67 const char *loc; 68 69 if (strlen(path) >= MAXNAMELEN) { 70 if (why) 71 *why = NAME_ERR_TOOLONG; 72 return (-1); 73 } 74 75 if (path[0] == '\0') { 76 if (why) 77 *why = NAME_ERR_EMPTY_COMPONENT; 78 return (-1); 79 } 80 81 for (loc = path; *loc; loc++) { 82 if (!valid_char(*loc)) { 83 if (why) { 84 *why = NAME_ERR_INVALCHAR; 85 *what = *loc; 86 } 87 return (-1); 88 } 89 } 90 return (0); 91 } 92 93 94 /* 95 * Permissions set name must start with the letter '@' followed by the 96 * same character restrictions as snapshot names, except that the name 97 * cannot exceed 64 characters. 98 */ 99 int 100 permset_namecheck(const char *path, namecheck_err_t *why, char *what) 101 { 102 if (strlen(path) >= ZFS_PERMSET_MAXLEN) { 103 if (why) 104 *why = NAME_ERR_TOOLONG; 105 return (-1); 106 } 107 108 if (path[0] != '@') { 109 if (why) { 110 *why = NAME_ERR_NO_AT; 111 *what = path[0]; 112 } 113 return (-1); 114 } 115 116 return (snapshot_namecheck(&path[1], why, what)); 117 } 118 119 /* 120 * Dataset names must be of the following form: 121 * 122 * [component][/]*[component][@component] 123 * 124 * Where each component is made up of alphanumeric characters plus the following 125 * characters: 126 * 127 * [-_.:%] 128 * 129 * We allow '%' here as we use that character internally to create unique 130 * names for temporary clones (for online recv). 131 */ 132 int 133 dataset_namecheck(const char *path, namecheck_err_t *why, char *what) 134 { 135 const char *loc, *end; 136 int found_snapshot; 137 138 /* 139 * Make sure the name is not too long. 140 * 141 * ZFS_MAXNAMELEN is the maximum dataset length used in the userland 142 * which is the same as MAXNAMELEN used in the kernel. 143 * If ZFS_MAXNAMELEN value is changed, make sure to cleanup all 144 * places using MAXNAMELEN. 145 */ 146 147 if (strlen(path) >= MAXNAMELEN) { 148 if (why) 149 *why = NAME_ERR_TOOLONG; 150 return (-1); 151 } 152 153 /* Explicitly check for a leading slash. */ 154 if (path[0] == '/') { 155 if (why) 156 *why = NAME_ERR_LEADING_SLASH; 157 return (-1); 158 } 159 160 if (path[0] == '\0') { 161 if (why) 162 *why = NAME_ERR_EMPTY_COMPONENT; 163 return (-1); 164 } 165 166 loc = path; 167 found_snapshot = 0; 168 for (;;) { 169 /* Find the end of this component */ 170 end = loc; 171 while (*end != '/' && *end != '@' && *end != '\0') 172 end++; 173 174 if (*end == '\0' && end[-1] == '/') { 175 /* trailing slashes are not allowed */ 176 if (why) 177 *why = NAME_ERR_TRAILING_SLASH; 178 return (-1); 179 } 180 181 /* Zero-length components are not allowed */ 182 if (loc == end) { 183 if (why) { 184 /* 185 * Make sure this is really a zero-length 186 * component and not a '@@'. 187 */ 188 if (*end == '@' && found_snapshot) { 189 *why = NAME_ERR_MULTIPLE_AT; 190 } else { 191 *why = NAME_ERR_EMPTY_COMPONENT; 192 } 193 } 194 195 return (-1); 196 } 197 198 /* Validate the contents of this component */ 199 while (loc != end) { 200 if (!valid_char(*loc) && *loc != '%') { 201 if (why) { 202 *why = NAME_ERR_INVALCHAR; 203 *what = *loc; 204 } 205 return (-1); 206 } 207 loc++; 208 } 209 210 /* If we've reached the end of the string, we're OK */ 211 if (*end == '\0') 212 return (0); 213 214 if (*end == '@') { 215 /* 216 * If we've found an @ symbol, indicate that we're in 217 * the snapshot component, and report a second '@' 218 * character as an error. 219 */ 220 if (found_snapshot) { 221 if (why) 222 *why = NAME_ERR_MULTIPLE_AT; 223 return (-1); 224 } 225 226 found_snapshot = 1; 227 } 228 229 /* 230 * If there is a '/' in a snapshot name 231 * then report an error 232 */ 233 if (*end == '/' && found_snapshot) { 234 if (why) 235 *why = NAME_ERR_TRAILING_SLASH; 236 return (-1); 237 } 238 239 /* Update to the next component */ 240 loc = end + 1; 241 } 242 } 243 244 245 /* 246 * mountpoint names must be of the following form: 247 * 248 * /[component][/]*[component][/] 249 */ 250 int 251 mountpoint_namecheck(const char *path, namecheck_err_t *why) 252 { 253 const char *start, *end; 254 255 /* 256 * Make sure none of the mountpoint component names are too long. 257 * If a component name is too long then the mkdir of the mountpoint 258 * will fail but then the mountpoint property will be set to a value 259 * that can never be mounted. Better to fail before setting the prop. 260 * Extra slashes are OK, they will be tossed by the mountpoint mkdir. 261 */ 262 263 if (path == NULL || *path != '/') { 264 if (why) 265 *why = NAME_ERR_LEADING_SLASH; 266 return (-1); 267 } 268 269 /* Skip leading slash */ 270 start = &path[1]; 271 do { 272 end = start; 273 while (*end != '/' && *end != '\0') 274 end++; 275 276 if (end - start >= MAXNAMELEN) { 277 if (why) 278 *why = NAME_ERR_TOOLONG; 279 return (-1); 280 } 281 start = end + 1; 282 283 } while (*end != '\0'); 284 285 return (0); 286 } 287 288 /* 289 * For pool names, we have the same set of valid characters as described in 290 * dataset names, with the additional restriction that the pool name must begin 291 * with a letter. The pool names 'raidz' and 'mirror' are also reserved names 292 * that cannot be used. 293 */ 294 int 295 pool_namecheck(const char *pool, namecheck_err_t *why, char *what) 296 { 297 const char *c; 298 299 /* 300 * Make sure the name is not too long. 301 * 302 * ZPOOL_MAXNAMELEN is the maximum pool length used in the userland 303 * which is the same as MAXNAMELEN used in the kernel. 304 * If ZPOOL_MAXNAMELEN value is changed, make sure to cleanup all 305 * places using MAXNAMELEN. 306 */ 307 if (strlen(pool) >= MAXNAMELEN) { 308 if (why) 309 *why = NAME_ERR_TOOLONG; 310 return (-1); 311 } 312 313 c = pool; 314 while (*c != '\0') { 315 if (!valid_char(*c)) { 316 if (why) { 317 *why = NAME_ERR_INVALCHAR; 318 *what = *c; 319 } 320 return (-1); 321 } 322 c++; 323 } 324 325 if (!(*pool >= 'a' && *pool <= 'z') && 326 !(*pool >= 'A' && *pool <= 'Z')) { 327 if (why) 328 *why = NAME_ERR_NOLETTER; 329 return (-1); 330 } 331 332 if (strcmp(pool, "mirror") == 0 || strcmp(pool, "raidz") == 0) { 333 if (why) 334 *why = NAME_ERR_RESERVED; 335 return (-1); 336 } 337 338 if (pool[0] == 'c' && (pool[1] >= '0' && pool[1] <= '9')) { 339 if (why) 340 *why = NAME_ERR_DISKLIKE; 341 return (-1); 342 } 343 344 return (0); 345 } 346