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#endif
74
75
76#ifdef BSD_KERNEL_PRIVATE
77
78/* VFS Supports "/..namedfork/rsrc" access. */
79#define NAMEDRSRCFORK		NAMEDSTREAMS
80
81
82#include <sys/queue.h>
83#include <sys/uio.h>
84#include <sys/vnode.h>
85#include <sys/mount.h>
86#include <sys/filedesc.h>
87
88#define PATHBUFLEN	256
89
90/*
91 * Encapsulation of namei parameters.
92 */
93struct nameidata {
94	/*
95	 * Arguments to namei/lookup.
96	 */
97	user_addr_t ni_dirp;		/* pathname pointer */
98	enum	uio_seg ni_segflg;	/* location of pathname */
99#if CONFIG_TRIGGERS
100	enum	path_operation ni_op;	/* intended operation, see enum path_operation in vnode.h */
101#endif /* CONFIG_TRIGGERS */
102	/*
103	 * Arguments to lookup.
104	 */
105	struct	vnode *ni_startdir;	/* starting directory */
106	struct	vnode *ni_rootdir;	/* logical root directory */
107        struct  vnode *ni_usedvp;       /* directory passed in via USEDVP */
108	/*
109	 * Results: returned from/manipulated by lookup
110	 */
111	struct	vnode *ni_vp;		/* vnode of result */
112	struct	vnode *ni_dvp;		/* vnode of intermediate directory */
113	/*
114	 * Shared between namei and lookup/commit routines.
115	 */
116	u_int	ni_pathlen;		/* remaining chars in path */
117	char	*ni_next;		/* next location in pathname */
118        char	ni_pathbuf[PATHBUFLEN];
119	u_long	ni_loopcnt;		/* count of symlinks encountered */
120
121	struct componentname ni_cnd;
122	int32_t ni_flag;
123	int ni_ncgeneration;		/* For a batched vnop, grab generation beforehand */
124};
125
126#define NAMEI_CONTLOOKUP	0x002    /* Continue processing a lookup which was partially processed in a compound VNOP */
127#define NAMEI_TRAILINGSLASH	0x004    /* There was at least one trailing slash after last component */
128#define NAMEI_UNFINISHED	0x008    /* We broke off a lookup to do a compound op */
129/*
130 * XXX Hack: we need to encode the intended VNOP in order to
131 * be able to include information about which operations a filesystem
132 * supports in the decision to break off a lookup early.
133 */
134#define NAMEI_COMPOUNDOPEN	0x010
135#define NAMEI_COMPOUNDREMOVE	0x020
136#define NAMEI_COMPOUNDMKDIR	0x040
137#define NAMEI_COMPOUNDRMDIR	0x080
138#define NAMEI_COMPOUNDRENAME	0x100
139#define NAMEI_COMPOUND_OP_MASK (NAMEI_COMPOUNDOPEN | NAMEI_COMPOUNDREMOVE | NAMEI_COMPOUNDMKDIR | NAMEI_COMPOUNDRMDIR | NAMEI_COMPOUNDRENAME)
140
141#ifdef KERNEL
142/*
143 * namei operational modifier flags, stored in ni_cnd.flags
144 * Also includes LOCKLEAF, LOCKPARENT, and WANTPARENT flags, defined above.
145 */
146#define	NOCACHE		0x00000020 /* name must not be left in cache */
147#define	NOFOLLOW	0x00000000 /* do not follow symbolic links (pseudo) */
148/* public FOLLOW	0x00000040    see vnode.h */
149#define	SHAREDLEAF	0x00000080 /* OK to have shared leaf lock */
150#define	MODMASK		0x100000fc /* mask of operational modifiers */
151/*
152 * Namei parameter descriptors.
153 *
154 * SAVESTART is set only by the callers of namei. It implies SAVENAME
155 * plus the addition of saving the parent directory that contains the
156 * name in ni_startdir. It allows repeated calls to lookup for the
157 * name being sought. The caller is responsible for releasing the
158 * buffer and for vrele'ing ni_startdir.
159 */
160#define	SAVENAME	0          /* save pathanme buffer ***obsolete */
161#define	NOCROSSMOUNT	0x00000100 /* do not cross mount points */
162#define	RDONLY		0x00000200 /* lookup with read-only semantics */
163#define	HASBUF		0x00000400 /* has allocated pathname buffer */
164#define DONOTAUTH	0x00000800 /* do not authorize during lookup */
165#define	SAVESTART	0x00001000 /* save starting directory */
166/* public ISDOTDOT	0x00002000    see vnode.h */
167/* public MAKEENTRY	0x00004000    see vnode.h */
168/* public ISLASTCN	0x00008000    see vnode.h */
169#define	ISSYMLINK	0x00010000 /* symlink needs interpretation */
170/* public ISWHITEOUT	0x00020000    see vnode.h */
171/* public DOWHITEOUT	0x00040000    see vnode.h */
172#define	WILLBEDIR	0x00080000 /* new files will be dirs; allow trailing / */
173#define	AUDITVNPATH1	0x00100000 /* audit the path/vnode info */
174#define	AUDITVNPATH2	0x00200000 /* audit the path/vnode info */
175#define	USEDVP		0x00400000 /* start the lookup at ndp.ni_dvp */
176#define	CN_VOLFSPATH	0x00800000 /* user path was a volfs style path */
177#define UNIONCREATED	0x02000000 /* union fs creation of vnode */
178#if NAMEDRSRCFORK
179#define CN_WANTSRSRCFORK 0x04000000
180#define CN_ALLOWRSRCFORK 0x08000000
181#endif
182#if CONFIG_SECLUDED_RENAME
183#ifdef BSD_KERNEL_PRIVATE
184#define CN_SECLUDE_RENAME 0x10000000 /*rename iff ¬(hard-linked ∨ opened ∨ mmaped)*/
185#endif
186#endif
187#define CN_NBMOUNTLOOK	0x20000000 /* do not block for cross mount lookups */
188#ifdef BSD_KERNEL_PRIVATE
189#define CN_SKIPNAMECACHE	0x40000000	/* skip cache during lookup(), allow FS to handle all components */
190#endif
191
192/*
193 * Initialization of an nameidata structure.
194 */
195
196#if CONFIG_TRIGGERS
197/* Note: vnode triggers require more precise path operation (ni_op) */
198
199#define NDINIT(ndp, op, pop, flags, segflg, namep, ctx) { \
200	(ndp)->ni_cnd.cn_nameiop = op; \
201	(ndp)->ni_op = pop; \
202	(ndp)->ni_cnd.cn_flags = flags; \
203	if ((segflg) == UIO_USERSPACE) { \
204		(ndp)->ni_segflg = ((IS_64BIT_PROCESS(vfs_context_proc(ctx))) ? UIO_USERSPACE64 : UIO_USERSPACE32); \
205	} \
206	else { \
207		(ndp)->ni_segflg = segflg; \
208	} \
209	(ndp)->ni_dirp = namep; \
210	(ndp)->ni_cnd.cn_context = ctx; \
211	(ndp)->ni_flag = 0; \
212	(ndp)->ni_cnd.cn_ndp = (ndp); \
213}
214#else
215#define NDINIT(ndp, op, _unused_, flags, segflg, namep, ctx) { \
216	(ndp)->ni_cnd.cn_nameiop = op; \
217	(ndp)->ni_cnd.cn_flags = flags; \
218	if ((segflg) == UIO_USERSPACE) { \
219		(ndp)->ni_segflg = ((IS_64BIT_PROCESS(vfs_context_proc(ctx))) ? UIO_USERSPACE64 : UIO_USERSPACE32); \
220	} \
221	else { \
222		(ndp)->ni_segflg = segflg; \
223	} \
224	(ndp)->ni_dirp = namep; \
225	(ndp)->ni_cnd.cn_context = ctx; \
226	(ndp)->ni_flag = 0; \
227	(ndp)->ni_cnd.cn_ndp = (ndp); \
228}
229#endif /* CONFIG_TRIGGERS */
230
231#endif /* KERNEL */
232
233/*
234 * This structure describes the elements in the cache of recent
235 * names looked up by namei.
236 */
237struct	namecache {
238	TAILQ_ENTRY(namecache)	nc_entry;	/* chain of all entries */
239	LIST_ENTRY(namecache)	nc_hash;	/* hash chain */
240        LIST_ENTRY(namecache)	nc_child;	/* chain of ncp's that are children of a vp */
241        union {
242	  LIST_ENTRY(namecache)	 nc_link;	/* chain of ncp's that 'name' a vp */
243	  TAILQ_ENTRY(namecache) nc_negentry;	/* chain of ncp's that 'name' a vp */
244	} nc_un;
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
252#ifdef KERNEL
253
254int	namei(struct nameidata *ndp);
255void	nameidone(struct nameidata *);
256int	lookup(struct nameidata *ndp);
257int	relookup(struct vnode *dvp, struct vnode **vpp,
258		struct componentname *cnp);
259int	lookup_traverse_union(vnode_t dvp, vnode_t *new_dvp, vfs_context_t ctx);
260void	lookup_compound_vnop_post_hook(int error, vnode_t dvp, vnode_t vp, struct nameidata *ndp, int did_create);
261
262/*
263 * namecache function prototypes
264 */
265void    cache_purgevfs(mount_t mp);
266int		cache_lookup_path(struct nameidata *ndp, struct componentname *cnp, vnode_t dp,
267			  vfs_context_t context, int *dp_authorized, vnode_t last_dp);
268
269void		vnode_cache_authorized_action(vnode_t vp, vfs_context_t context, kauth_action_t action);
270void		vnode_uncache_authorized_action(vnode_t vp, kauth_action_t action);
271boolean_t	vnode_cache_is_stale(vnode_t vp);
272boolean_t	vnode_cache_is_authorized(vnode_t vp, vfs_context_t context, kauth_action_t action);
273int 		lookup_validate_creation_path(struct nameidata *ndp);
274int		namei_compound_available(vnode_t dp, struct nameidata *ndp);
275
276#endif /* KERNEL */
277
278/*
279 * Stats on usefulness of namei caches.
280 */
281struct	nchstats {
282	long	ncs_goodhits;		/* hits that we can really use */
283	long	ncs_neghits;		/* negative hits that we can use */
284	long	ncs_badhits;		/* hits we must drop */
285	long	ncs_miss;		/* misses */
286	long	ncs_pass2;		/* names found with passes == 2 */
287	long	ncs_2passes;		/* number of times we attempt it */
288        long	ncs_stolen;
289        long	ncs_enters;
290        long	ncs_deletes;
291        long	ncs_badvid;
292};
293#endif /* BSD_KERNEL_PRIVATE */
294
295#endif /* !_SYS_NAMEI_H_ */
296