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 */
99struct 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
149#ifdef KERNEL
150/*
151 * namei operational modifier flags, stored in ni_cnd.flags
152 * Also includes LOCKLEAF, LOCKPARENT, and WANTPARENT flags, defined above.
153 */
154#define NOCACHE 0x00000020 /* name must not be left in cache */
155#define NOFOLLOW 0x00000000 /* do not follow symbolic links (pseudo) */
156/* public FOLLOW 0x00000040 see vnode.h */
157#define SHAREDLEAF 0x00000080 /* OK to have shared leaf lock */
158#define MODMASK 0x100000fc /* mask of operational modifiers */
159/*
160 * Namei parameter descriptors.
161 *
162 * SAVESTART is set only by the callers of namei. It implies SAVENAME
163 * plus the addition of saving the parent directory that contains the
164 * name in ni_startdir. It allows repeated calls to lookup for the
165 * name being sought. The caller is responsible for releasing the
166 * buffer and for vrele'ing ni_startdir.
167 */
168#define SAVENAME 0 /* save pathanme buffer ***obsolete */
169#define NOCROSSMOUNT 0x00000100 /* do not cross mount points */
170#define RDONLY 0x00000200 /* lookup with read-only semantics */
171#define HASBUF 0x00000400 /* has allocated pathname buffer */
172#define DONOTAUTH 0x00000800 /* do not authorize during lookup */
173#define SAVESTART 0x00001000 /* save starting directory */
174/* public ISDOTDOT 0x00002000 see vnode.h */
175/* public MAKEENTRY 0x00004000 see vnode.h */
176/* public ISLASTCN 0x00008000 see vnode.h */
177#define ISSYMLINK 0x00010000 /* symlink needs interpretation */
178/* public ISWHITEOUT 0x00020000 see vnode.h */
179/* public DOWHITEOUT 0x00040000 see vnode.h */
180#define WILLBEDIR 0x00080000 /* new files will be dirs; allow trailing / */
181#define AUDITVNPATH1 0x00100000 /* audit the path/vnode info */
182#define AUDITVNPATH2 0x00200000 /* audit the path/vnode info */
183#define USEDVP 0x00400000 /* start the lookup at ndp.ni_dvp */
184#define CN_VOLFSPATH 0x00800000 /* user path was a volfs style path */
185#define CN_FIRMLINK_NOFOLLOW 0x01000000 /* Do not follow firm links */
186#define UNIONCREATED 0x02000000 /* union fs creation of vnode */
187#if NAMEDRSRCFORK
188#define CN_WANTSRSRCFORK 0x04000000
189#define CN_ALLOWRSRCFORK 0x08000000
190#endif // NAMEDRSRCFORK
191// CN_SECLUDE_RENAME is defined above as 0x10000000 (SPI)
192#define CN_NBMOUNTLOOK 0x20000000 /* do not block for cross mount lookups */
193#ifdef BSD_KERNEL_PRIVATE
194#define CN_SKIPNAMECACHE 0x40000000 /* skip cache during lookup(), allow FS to handle all components */
195#endif
196// CN_RAW_ENCRYPTED is defined above as 0x80000000 (SPI)
197
198/*
199 * Initialization of an nameidata structure.
200 */
201
202#define NDINIT(ndp, op, pop, flags, segflg, namep, ctx) { \
203 (ndp)->ni_cnd.cn_nameiop = op; \
204 (ndp)->ni_op = pop; \
205 (ndp)->ni_cnd.cn_flags = flags; \
206 if ((segflg) == UIO_USERSPACE) { \
207 (ndp)->ni_segflg = (vfs_context_is64bit(ctx) ? UIO_USERSPACE64 : UIO_USERSPACE32); \
208 } \
209 else { \
210 (ndp)->ni_segflg = segflg; \
211 } \
212 (ndp)->ni_dirp = namep; \
213 (ndp)->ni_cnd.cn_context = ctx; \
214 (ndp)->ni_flag = 0; \
215 (ndp)->ni_cnd.cn_ndp = (ndp); \
216}
217
218#endif /* KERNEL */
219
220/*
221 * This structure describes the elements in the cache of recent
222 * names looked up by namei.
223 */
224struct namecache {
225 TAILQ_ENTRY(namecache) nc_entry; /* chain of all entries */
226 TAILQ_ENTRY(namecache) nc_child; /* chain of ncp's that are children of a vp */
227 union {
228 LIST_ENTRY(namecache) nc_link; /* chain of ncp's that 'name' a vp */
229 TAILQ_ENTRY(namecache) nc_negentry; /* chain of ncp's that 'name' a vp */
230 } nc_un;
231 struct smrq_link nc_hash; /* hash chain */
232 uint32_t nc_vid; /* vid for nc_vp */
233 uint32_t nc_counter; /* flags */
234 vnode_t nc_dvp; /* vnode of parent of name */
235 vnode_t nc_vp; /* vnode the name refers to */
236 unsigned int nc_hashval; /* hashval of stringname */
237 const char *nc_name; /* pointer to segment name in string cache */
238};
239
240#define NC_VALID 0x01 /* counter value with this bit set (i.e. odd number) represents an valid/in-use namecache struct */
241
242#ifdef KERNEL
243
244int namei(struct nameidata *ndp);
245void nameidone(struct nameidata *);
246int lookup(struct nameidata *ndp);
247int relookup(struct vnode *dvp, struct vnode **vpp,
248 struct componentname *cnp);
249#if CONFIG_UNION_MOUNTS
250int lookup_traverse_union(vnode_t dvp, vnode_t *new_dvp, vfs_context_t ctx);
251#endif /* CONFIG_UNION_MOUNTS */
252void lookup_compound_vnop_post_hook(int error, vnode_t dvp, vnode_t vp, struct nameidata *ndp, int did_create);
253void kdebug_lookup(struct vnode *dp, struct componentname *cnp);
254
255/*
256 * namecache function prototypes
257 */
258void cache_purgevfs(mount_t mp);
259int cache_lookup_path(struct nameidata *ndp, struct componentname *cnp, vnode_t dp,
260 vfs_context_t context, int *dp_authorized, vnode_t last_dp);
261
262void vnode_cache_authorized_action(vnode_t vp, vfs_context_t context, kauth_action_t action);
263void vnode_uncache_authorized_action(vnode_t vp, kauth_action_t action);
264boolean_t vnode_cache_is_stale(vnode_t vp);
265boolean_t vnode_cache_is_authorized(vnode_t vp, vfs_context_t context, kauth_action_t action);
266int lookup_validate_creation_path(struct nameidata *ndp);
267int namei_compound_available(vnode_t dp, struct nameidata *ndp);
268
269#endif /* KERNEL */
270
271/*
272 * Stats on usefulness of namei caches.
273 */
274struct nchstats {
275 long ncs_goodhits; /* hits that we can really use */
276 long ncs_neghits; /* negative hits that we can use */
277 long ncs_badhits; /* hits we must drop */
278 long ncs_miss; /* misses */
279 long ncs_pass2; /* names found with passes == 2 */
280 long ncs_2passes; /* number of times we attempt it */
281 long ncs_stolen;
282 long ncs_enters;
283 long ncs_deletes;
284 long ncs_badvid;
285};
286#endif /* BSD_KERNEL_PRIVATE */
287
288#endif /* !_SYS_NAMEI_H_ */
289