1 /* 2 * Copyright (c) 2000-2014 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */ 29 /* 30 * Copyright (c) 1985, 1989, 1991, 1993 31 * The Regents of the University of California. All rights reserved. 32 * 33 * Redistribution and use in source and binary forms, with or without 34 * modification, are permitted provided that the following conditions 35 * are met: 36 * 1. Redistributions of source code must retain the above copyright 37 * notice, this list of conditions and the following disclaimer. 38 * 2. Redistributions in binary form must reproduce the above copyright 39 * notice, this list of conditions and the following disclaimer in the 40 * documentation and/or other materials provided with the distribution. 41 * 3. All advertising materials mentioning features or use of this software 42 * must display the following acknowledgement: 43 * This product includes software developed by the University of 44 * California, Berkeley and its contributors. 45 * 4. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)namei.h 8.4 (Berkeley) 8/20/94 62 */ 63 64 #ifndef _SYS_NAMEI_H_ 65 #define _SYS_NAMEI_H_ 66 67 #include <sys/appleapiopts.h> 68 69 #ifdef KERNEL 70 #define LOCKLEAF 0x0004 /* lock inode on return */ 71 #define LOCKPARENT 0x0008 /* want parent vnode returned */ 72 #define WANTPARENT 0x0010 /* want parent vnode returned */ 73 74 #ifdef KERNEL_PRIVATE 75 #define CN_SECLUDE_RENAME 0x10000000 /*rename iff ￢(hard-linked ∨ opened ∨ mmaped)*/ 76 #define CN_RAW_ENCRYPTED 0x80000000 /* Look-up is for RO raw encrypted access. */ 77 #endif 78 79 #endif // KERNEL 80 81 #ifdef BSD_KERNEL_PRIVATE 82 83 /* VFS Supports "/..namedfork/rsrc" access. */ 84 #define NAMEDRSRCFORK NAMEDSTREAMS 85 86 87 #include <sys/queue.h> 88 #include <kern/smr.h> 89 #include <sys/uio.h> 90 #include <sys/vnode.h> 91 #include <sys/mount.h> 92 #include <sys/filedesc.h> 93 94 #define PATHBUFLEN 256 95 96 /* 97 * Encapsulation of namei parameters. 98 */ 99 struct nameidata { 100 /* 101 * Arguments to namei/lookup. 102 */ 103 user_addr_t ni_dirp; /* pathname pointer */ 104 enum uio_seg ni_segflg; /* location of pathname */ 105 enum path_operation ni_op; /* intended operation, see enum path_operation in vnode.h */ 106 /* 107 * Arguments to lookup. 108 */ 109 struct vnode *ni_startdir; /* starting directory */ 110 struct vnode *ni_rootdir; /* logical root directory */ 111 struct vnode *ni_usedvp; /* directory passed in via USEDVP */ 112 /* 113 * Results: returned from/manipulated by lookup 114 */ 115 struct vnode *ni_vp; /* vnode of result */ 116 struct vnode *ni_dvp; /* vnode of intermediate directory */ 117 /* 118 * Shared between namei and lookup/commit routines. 119 */ 120 u_int ni_pathlen; /* remaining chars in path */ 121 char *ni_next; /* next location in pathname */ 122 char ni_pathbuf[PATHBUFLEN]; 123 u_long ni_loopcnt; /* count of symlinks encountered */ 124 125 struct componentname ni_cnd; 126 int32_t ni_flag; 127 int ni_ncgeneration; /* For a batched vnop, grab generation beforehand */ 128 }; 129 130 #define NAMEI_CONTLOOKUP 0x002 /* Continue processing a lookup which was partially processed in a compound VNOP */ 131 #define NAMEI_TRAILINGSLASH 0x004 /* There was at least one trailing slash after last component */ 132 #define NAMEI_UNFINISHED 0x008 /* We broke off a lookup to do a compound op */ 133 134 /* 135 * XXX Hack: we need to encode the intended VNOP in order to 136 * be able to include information about which operations a filesystem 137 * supports in the decision to break off a lookup early. 138 */ 139 #define NAMEI_COMPOUNDOPEN 0x010 140 #define NAMEI_COMPOUNDREMOVE 0x020 141 #define NAMEI_COMPOUNDMKDIR 0x040 142 #define NAMEI_COMPOUNDRMDIR 0x080 143 #define NAMEI_COMPOUNDRENAME 0x100 144 #define NAMEI_COMPOUND_OP_MASK (NAMEI_COMPOUNDOPEN | NAMEI_COMPOUNDREMOVE | NAMEI_COMPOUNDMKDIR | NAMEI_COMPOUNDRMDIR | NAMEI_COMPOUNDRENAME) 145 146 #define NAMEI_NOFOLLOW_ANY 0x1000 /* no symlinks allowed in the path */ 147 #define NAMEI_ROOTDIR 0x2000 /* Limit lookup to ni_rootdir (similar to chroot) */ 148 #define NAMEI_RESOLVE_BENEATH 0x4000 /* path resolution must not escape the starting directory */ 149 #define NAMEI_NODOTDOT 0x8000 /* prevent '..' path traversal */ 150 151 #define NAMEI_LOCAL 0x10000 /* prevent a path lookup into a network filesystem */ 152 #define NAMEI_NODEVFS 0x20000 /* prevent a path lookup into `devfs` filesystem */ 153 #define NAMEI_IMMOVABLE 0x40000 /* prevent a path lookup into a removable filesystem */ 154 #define NAMEI_NOXATTRS 0x80000 /* prevent a path lookup on named streams */ 155 156 #define NAMEI_UNIQUE 0x100000 /* prevent a path lookup from succeeding on a vnode with multiple links */ 157 158 #ifdef KERNEL 159 /* 160 * namei operational modifier flags, stored in ni_cnd.flags 161 * Also includes LOCKLEAF, LOCKPARENT, and WANTPARENT flags, defined above. 162 */ 163 #define NOCACHE 0x00000020 /* name must not be left in cache */ 164 #define NOFOLLOW 0x00000000 /* do not follow symbolic links (pseudo) */ 165 /* public FOLLOW 0x00000040 see vnode.h */ 166 #define SHAREDLEAF 0x00000080 /* OK to have shared leaf lock */ 167 #define MODMASK 0x100000fc /* mask of operational modifiers */ 168 /* 169 * Namei parameter descriptors. 170 * 171 * SAVESTART is set only by the callers of namei. It implies SAVENAME 172 * plus the addition of saving the parent directory that contains the 173 * name in ni_startdir. It allows repeated calls to lookup for the 174 * name being sought. The caller is responsible for releasing the 175 * buffer and for vrele'ing ni_startdir. 176 */ 177 #define SAVENAME 0 /* save pathanme buffer ***obsolete */ 178 #define NOCROSSMOUNT 0x00000100 /* do not cross mount points */ 179 #define RDONLY 0x00000200 /* lookup with read-only semantics */ 180 #define HASBUF 0x00000400 /* has allocated pathname buffer */ 181 #define DONOTAUTH 0x00000800 /* do not authorize during lookup */ 182 #define SAVESTART 0x00001000 /* save starting directory */ 183 /* public ISDOTDOT 0x00002000 see vnode.h */ 184 /* public MAKEENTRY 0x00004000 see vnode.h */ 185 /* public ISLASTCN 0x00008000 see vnode.h */ 186 #define ISSYMLINK 0x00010000 /* symlink needs interpretation */ 187 /* public ISWHITEOUT 0x00020000 see vnode.h */ 188 /* public DOWHITEOUT 0x00040000 see vnode.h */ 189 #define WILLBEDIR 0x00080000 /* new files will be dirs; allow trailing / */ 190 #define AUDITVNPATH1 0x00100000 /* audit the path/vnode info */ 191 #define AUDITVNPATH2 0x00200000 /* audit the path/vnode info */ 192 #define USEDVP 0x00400000 /* start the lookup at ndp.ni_dvp */ 193 #define CN_VOLFSPATH 0x00800000 /* user path was a volfs style path */ 194 #define CN_FIRMLINK_NOFOLLOW 0x01000000 /* Do not follow firm links */ 195 #if NAMEDSTREAMS 196 #define MARKISSHADOW 0x02000000 /* only for getshadowfile() */ 197 #endif 198 #if NAMEDRSRCFORK 199 #define CN_WANTSRSRCFORK 0x04000000 200 #define CN_ALLOWRSRCFORK 0x08000000 201 #endif // NAMEDRSRCFORK 202 // CN_SECLUDE_RENAME is defined above as 0x10000000 (SPI) 203 #define CN_NBMOUNTLOOK 0x20000000 /* do not block for cross mount lookups */ 204 #ifdef BSD_KERNEL_PRIVATE 205 #define CN_SKIPNAMECACHE 0x40000000 /* skip cache during lookup(), allow FS to handle all components */ 206 #endif 207 // CN_RAW_ENCRYPTED is defined above as 0x80000000 (SPI) 208 209 /* 210 * Initialization of an nameidata structure. 211 */ 212 213 #define NDINIT(ndp, op, pop, flags, segflg, namep, ctx) { \ 214 (ndp)->ni_cnd.cn_nameiop = op; \ 215 (ndp)->ni_op = pop; \ 216 (ndp)->ni_cnd.cn_flags = flags; \ 217 if ((segflg) == UIO_USERSPACE) { \ 218 (ndp)->ni_segflg = (vfs_context_is64bit(ctx) ? UIO_USERSPACE64 : UIO_USERSPACE32); \ 219 } \ 220 else { \ 221 (ndp)->ni_segflg = segflg; \ 222 } \ 223 (ndp)->ni_dirp = namep; \ 224 (ndp)->ni_cnd.cn_context = ctx; \ 225 (ndp)->ni_flag = 0; \ 226 (ndp)->ni_cnd.cn_ndp = (ndp); \ 227 } 228 229 #endif /* KERNEL */ 230 231 /* 232 * This structure describes the elements in the cache of recent 233 * names looked up by namei. 234 */ 235 struct namecache { 236 TAILQ_ENTRY(namecache) nc_entry; /* chain of all entries */ 237 TAILQ_ENTRY(namecache) nc_child; /* chain of ncp's that are children of a vp */ 238 union { 239 LIST_ENTRY(namecache) nc_link; /* chain of ncp's that 'name' a vp */ 240 TAILQ_ENTRY(namecache) nc_negentry; /* chain of ncp's that 'name' a vp */ 241 } nc_un; 242 struct smrq_link nc_hash; /* hash chain */ 243 uint32_t nc_vid; /* vid for nc_vp */ 244 uint32_t nc_counter; /* flags */ 245 vnode_t nc_dvp; /* vnode of parent of name */ 246 vnode_t nc_vp; /* vnode the name refers to */ 247 unsigned int nc_hashval; /* hashval of stringname */ 248 const char *nc_name; /* pointer to segment name in string cache */ 249 }; 250 251 #define NC_VALID 0x01 /* counter value with this bit set (i.e. odd number) represents an valid/in-use namecache struct */ 252 253 #ifdef KERNEL 254 255 int namei(struct nameidata *ndp); 256 void nameidone(struct nameidata *); 257 int lookup(struct nameidata *ndp); 258 int relookup(struct vnode *dvp, struct vnode **vpp, 259 struct componentname *cnp); 260 #if CONFIG_UNION_MOUNTS 261 int lookup_traverse_union(vnode_t dvp, vnode_t *new_dvp, vfs_context_t ctx); 262 #endif /* CONFIG_UNION_MOUNTS */ 263 int lookup_check_for_resolve_prefix(char *path, size_t pathbuflen, size_t len, uint32_t *resolve_flags, size_t *prefix_len); 264 void lookup_compound_vnop_post_hook(int error, vnode_t dvp, vnode_t vp, struct nameidata *ndp, int did_create); 265 void kdebug_lookup(struct vnode *dp, struct componentname *cnp); 266 267 /* 268 * namecache function prototypes 269 */ 270 void cache_purgevfs(mount_t mp); 271 int cache_lookup_path(struct nameidata *ndp, struct componentname *cnp, vnode_t dp, 272 vfs_context_t context, int *dp_authorized, vnode_t last_dp); 273 274 void vnode_cache_authorized_action(vnode_t vp, vfs_context_t context, kauth_action_t action); 275 void vnode_uncache_authorized_action(vnode_t vp, kauth_action_t action); 276 boolean_t vnode_cache_is_stale(vnode_t vp); 277 boolean_t vnode_cache_is_authorized(vnode_t vp, vfs_context_t context, kauth_action_t action); 278 int lookup_validate_creation_path(struct nameidata *ndp); 279 int namei_compound_available(vnode_t dp, struct nameidata *ndp); 280 281 #endif /* KERNEL */ 282 283 /* 284 * Stats on usefulness of namei caches. 285 */ 286 struct nchstats { 287 long ncs_goodhits; /* hits that we can really use */ 288 long ncs_neghits; /* negative hits that we can use */ 289 long ncs_badhits; /* hits we must drop */ 290 long ncs_miss; /* misses */ 291 long ncs_pass2; /* names found with passes == 2 */ 292 long ncs_2passes; /* number of times we attempt it */ 293 long ncs_stolen; 294 long ncs_enters; 295 long ncs_deletes; 296 long ncs_badvid; 297 }; 298 #endif /* BSD_KERNEL_PRIVATE */ 299 300 #endif /* !_SYS_NAMEI_H_ */ 301