/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* * Copyright (c) 2013, 2016 by Delphix. All rights reserved. */ /* * Common name validation routines for ZFS. These routines are shared by the * userland code as well as the ioctl() layer to ensure that we don't * inadvertently expose a hole through direct ioctl()s that never gets tested. * In userland, however, we want significantly more information about _why_ the * name is invalid. In the kernel, we only care whether it's valid or not. * Each routine therefore takes a 'namecheck_err_t' which describes exactly why * the name failed to validate. */ #if defined(_KERNEL) #include <sys/systm.h> #else #include <string.h> #endif #include <sys/dsl_dir.h> #include <sys/param.h> #include <sys/nvpair.h> #include "zfs_namecheck.h" #include "zfs_deleg.h" /* * Deeply nested datasets can overflow the stack, so we put a limit * in the amount of nesting a path can have. zfs_max_dataset_nesting * can be tuned temporarily to fix existing datasets that exceed our * predefined limit. */ int zfs_max_dataset_nesting = 50; static int valid_char(char c) { return ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '-' || c == '_' || c == '.' || c == ':' || c == ' '); } /* * Looks at a path and returns its level of nesting (depth). */ int get_dataset_depth(const char *path) { const char *loc = path; int nesting = 0; /* * Keep track of nesting until you hit the end of the * path or found the snapshot/bookmark seperator. */ for (int i = 0; loc[i] != '\0' && loc[i] != '@' && loc[i] != '#'; i++) { if (loc[i] == '/') nesting++; } return (nesting); } /* * Snapshot names must be made up of alphanumeric characters plus the following * characters: * * [-_.: ] * * Returns 0 on success, -1 on error. */ int zfs_component_namecheck(const char *path, namecheck_err_t *why, char *what) { const char *loc; if (strlen(path) >= ZFS_MAX_DATASET_NAME_LEN) { if (why) *why = NAME_ERR_TOOLONG; return (-1); } if (path[0] == '\0') { if (why) *why = NAME_ERR_EMPTY_COMPONENT; return (-1); } for (loc = path; *loc; loc++) { if (!valid_char(*loc)) { if (why) { *why = NAME_ERR_INVALCHAR; *what = *loc; } return (-1); } } return (0); } /* * Permissions set name must start with the letter '@' followed by the * same character restrictions as snapshot names, except that the name * cannot exceed 64 characters. * * Returns 0 on success, -1 on error. */ int permset_namecheck(const char *path, namecheck_err_t *why, char *what) { if (strlen(path) >= ZFS_PERMSET_MAXLEN) { if (why) *why = NAME_ERR_TOOLONG; return (-1); } if (path[0] != '@') { if (why) { *why = NAME_ERR_NO_AT; *what = path[0]; } return (-1); } return (zfs_component_namecheck(&path[1], why, what)); } /* * Dataset paths should not be deeper than zfs_max_dataset_nesting * in terms of nesting. * * Returns 0 on success, -1 on error. */ int dataset_nestcheck(const char *path) { return ((get_dataset_depth(path) < zfs_max_dataset_nesting) ? 0 : -1); } /* * Entity names must be of the following form: * * [component/]*[component][(@|#)component]? * * Where each component is made up of alphanumeric characters plus the following * characters: * * [-_.:%] * * We allow '%' here as we use that character internally to create unique * names for temporary clones (for online recv). * * Returns 0 on success, -1 on error. */ int entity_namecheck(const char *path, namecheck_err_t *why, char *what) { const char *end; /* * Make sure the name is not too long. */ if (strlen(path) >= ZFS_MAX_DATASET_NAME_LEN) { if (why) *why = NAME_ERR_TOOLONG; return (-1); } /* Explicitly check for a leading slash. */ if (path[0] == '/') { if (why) *why = NAME_ERR_LEADING_SLASH; return (-1); } if (path[0] == '\0') { if (why) *why = NAME_ERR_EMPTY_COMPONENT; return (-1); } const char *start = path; boolean_t found_delim = B_FALSE; for (;;) { /* Find the end of this component */ end = start; while (*end != '/' && *end != '@' && *end != '#' && *end != '\0') end++; if (*end == '\0' && end[-1] == '/') { /* trailing slashes are not allowed */ if (why) *why = NAME_ERR_TRAILING_SLASH; return (-1); } /* Validate the contents of this component */ for (const char *loc = start; loc != end; loc++) { if (!valid_char(*loc) && *loc != '%') { if (why) { *why = NAME_ERR_INVALCHAR; *what = *loc; } return (-1); } } /* Snapshot or bookmark delimiter found */ if (*end == '@' || *end == '#') { /* Multiple delimiters are not allowed */ if (found_delim != 0) { if (why) *why = NAME_ERR_MULTIPLE_DELIMITERS; return (-1); } found_delim = B_TRUE; } /* Zero-length components are not allowed */ if (start == end) { if (why) *why = NAME_ERR_EMPTY_COMPONENT; return (-1); } /* If we've reached the end of the string, we're OK */ if (*end == '\0') return (0); /* * If there is a '/' in a snapshot or bookmark name * then report an error */ if (*end == '/' && found_delim != 0) { if (why) *why = NAME_ERR_TRAILING_SLASH; return (-1); } /* Update to the next component */ start = end + 1; } } /* * Dataset is any entity, except bookmark */ int dataset_namecheck(const char *path, namecheck_err_t *why, char *what) { int ret = entity_namecheck(path, why, what); if (ret == 0 && strchr(path, '#') != NULL) { if (why != NULL) { *why = NAME_ERR_INVALCHAR; *what = '#'; } return (-1); } return (ret); } /* * mountpoint names must be of the following form: * * /[component][/]*[component][/] * * Returns 0 on success, -1 on error. */ int mountpoint_namecheck(const char *path, namecheck_err_t *why) { const char *start, *end; /* * Make sure none of the mountpoint component names are too long. * If a component name is too long then the mkdir of the mountpoint * will fail but then the mountpoint property will be set to a value * that can never be mounted. Better to fail before setting the prop. * Extra slashes are OK, they will be tossed by the mountpoint mkdir. */ if (path == NULL || *path != '/') { if (why) *why = NAME_ERR_LEADING_SLASH; return (-1); } /* Skip leading slash */ start = &path[1]; do { end = start; while (*end != '/' && *end != '\0') end++; if (end - start >= ZFS_MAX_DATASET_NAME_LEN) { if (why) *why = NAME_ERR_TOOLONG; return (-1); } start = end + 1; } while (*end != '\0'); return (0); } /* * For pool names, we have the same set of valid characters as described in * dataset names, with the additional restriction that the pool name must begin * with a letter. The pool names 'raidz' and 'mirror' are also reserved names * that cannot be used. * * Returns 0 on success, -1 on error. */ int pool_namecheck(const char *pool, namecheck_err_t *why, char *what) { const char *c; /* * Make sure the name is not too long. * If we're creating a pool with version >= SPA_VERSION_DSL_SCRUB (v11) * we need to account for additional space needed by the origin ds which * will also be snapshotted: "poolname"+"/"+"$ORIGIN"+"@"+"$ORIGIN". * Play it safe and enforce this limit even if the pool version is < 11 * so it can be upgraded without issues. */ if (strlen(pool) >= (ZFS_MAX_DATASET_NAME_LEN - 2 - strlen(ORIGIN_DIR_NAME) * 2)) { if (why) *why = NAME_ERR_TOOLONG; return (-1); } c = pool; while (*c != '\0') { if (!valid_char(*c)) { if (why) { *why = NAME_ERR_INVALCHAR; *what = *c; } return (-1); } c++; } if (!(*pool >= 'a' && *pool <= 'z') && !(*pool >= 'A' && *pool <= 'Z')) { if (why) *why = NAME_ERR_NOLETTER; return (-1); } if (strcmp(pool, "mirror") == 0 || strcmp(pool, "raidz") == 0) { if (why) *why = NAME_ERR_RESERVED; return (-1); } if (pool[0] == 'c' && (pool[1] >= '0' && pool[1] <= '9')) { if (why) *why = NAME_ERR_DISKLIKE; return (-1); } return (0); }
