xref: /dragonfly/sys/sys/nlookup.h (revision 7485684f)
1 /*
2  * Copyright (c) 2004 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #ifndef _SYS_NLOOKUP_H_
36 #define	_SYS_NLOOKUP_H_
37 
38 #ifndef _SYS_NAMECACHE_H_
39 #include <sys/namecache.h>
40 #endif
41 #ifndef _SYS_FILE_H_
42 #include <sys/file.h>
43 #endif
44 
45 struct vnode;
46 struct vattr;
47 struct vattr_lite;
48 struct mount;
49 struct thread;
50 struct ucred;
51 
52 /*
53  * nlookup component
54  */
55 struct nlcomponent {
56 	char		*nlc_nameptr;
57 	int		nlc_namelen;
58 };
59 
60 /*
61  * Encapsulation of nlookup parameters.
62  *
63  * Note on nl_flags and nl_op: nl_flags supports a simplified subset of
64  * namei's original CNP flags.  nl_op (e.g. NAMEI_*) does no in any way
65  * effect the state of the returned namecache and is only used to enforce
66  * access checks.
67  */
68 struct nlookupdata {
69 	/*
70 	 * These fields are setup by nlookup_init() with nl_nch set to
71 	 * the current directory if a process or the root directory if
72 	 * a pure thread.  The result from nlookup() will be returned in
73 	 * nl_nch.
74 	 */
75 	struct nchandle nl_nch;		/* result */
76 	struct nchandle *nl_basench;	/* start-point directory */
77 	struct nchandle nl_rootnch;	/* root directory */
78 	struct nchandle nl_jailnch;	/* jail directory */
79 
80 	char		*nl_path;	/* path buffer */
81 	struct thread	*nl_td;		/* thread requesting the nlookup */
82 	struct ucred	*nl_cred;	/* credentials for nlookup */
83 	struct vnode	*nl_dvp;	/* NLC_REFDVP */
84 
85 	int		nl_flags;	/* operations flags */
86 	int		nl_loopcnt;	/* symlinks encountered */
87 	int		nl_dir_error;	/* error assoc w/intermediate dir */
88 	int		nl_elmno;	/* iteration# to help caches */
89 
90 	/*
91 	 * These fields are populated by vn_open().  nlookup_done() will
92 	 * vn_close() a non-NULL vp so if you extract it be sure to NULL out
93 	 * nl_open_vp.
94 	 */
95 	struct vnode	*nl_open_vp;
96 	int		nl_vp_fmode;
97 };
98 
99 /*
100  * NOTE: nlookup() flags related to open checks do not actually perform
101  *	 any modifying operation.  e.g. the file isn't created, truncated,
102  *	 etc.  vn_open() handles that.
103  */
104 #define NLC_FOLLOW		0x00000001	/* follow leaf symlink */
105 #define NLC_NOCROSSMOUNT	0x00000002	/* do not cross mount points */
106 #define NLC_HASBUF		0x00000004	/* nl_path is allocated */
107 #define NLC_ISWHITEOUT		0x00000008
108 #define NLC_WILLBEDIR		0x00000010
109 #define NLC_NCPISLOCKED		0x00000020
110 #define NLC_LOCKVP		0x00000040	/* nl_open_vp from vn_open */
111 #define NLC_CREATE		0x00000080	/* do create checks */
112 #define NLC_DELETE		0x00000100	/* do delete checks */
113 #define NLC_RENAME_DST		0x00000200	/* do rename checks (target) */
114 #define NLC_OPEN		0x00000400	/* do open checks */
115 #define NLC_TRUNCATE		0x00000800	/* do truncation checks */
116 #define NLC_HLINK		0x00001000	/* do hardlink checks */
117 #define NLC_RENAME_SRC		0x00002000	/* do rename checks (source) */
118 #define NLC_SHAREDLOCK		0x00004000	/* allow shared ncp & vp lock */
119 #define NLC_IGNBADDIR		0x00008000	/* used by umount */
120 #define NLC_NFS_RDONLY		0x00010000	/* set by nfs_namei() only */
121 #define NLC_NFS_NOSOFTLINKTRAV	0x00020000	/* do not traverse softlnks */
122 #define NLC_REFDVP		0x00040000	/* set ref'd/unlocked nl_dvp */
123 #define NLC_EXCLLOCK_IFEXEC	0x00080000	/* use excl lock if 'x' */
124 
125 #define NLC_APPEND		0x00100000	/* open check: append */
126 #define NLC_NLNCH_NOINIT	0x00200000	/* caller will initialize */
127 
128 #define NLC_READ		0x00400000	/* require read access */
129 #define NLC_WRITE		0x00800000	/* require write access */
130 #define NLC_EXEC		0x01000000	/* require execute access */
131 #define NLC_EXCL		0x02000000	/* open check: exclusive */
132 #define NLC_OWN			0x04000000	/* open check: owner override */
133 #define NLC_BORROWCRED		0x08000000	/* cred ref borrowed */
134 #define NLC_STICKY		0x10000000	/* indicate sticky case */
135 #define NLC_APPENDONLY		0x20000000	/* indicate append-only */
136 #define NLC_IMMUTABLE		0x40000000	/* indicate immutable set */
137 #define NLC_WRITABLE		0x80000000	/* indicate writeable */
138 
139 /*
140  * All checks.  If any of these bits are set general user/group/world
141  * permission checks will be done by nlookup().
142  */
143 #define NLC_ALLCHKS		(NLC_CREATE | NLC_DELETE | NLC_RENAME_DST | \
144 				 NLC_OPEN | NLC_TRUNCATE | NLC_RENAME_SRC | \
145 				 NLC_READ | NLC_WRITE | NLC_EXEC | NLC_OWN)
146 
147 #define NLC_MODIFYING_MASK	(NLC_CREATE | NLC_DELETE | NLC_RENAME_DST | \
148 				 NLC_RENAME_SRC)
149 
150 #ifdef _KERNEL
151 #include <sys/_uio.h>
152 
153 int	naccess_lva(struct vattr_lite *lvap, int nflags, struct ucred *cred);
154 int	nlookup(struct nlookupdata *);
155 void	nlookup_done(struct nlookupdata *);
156 void	nlookup_done_at(struct nlookupdata *, struct file *);
157 int	nlookup_init(struct nlookupdata *, const char *, enum uio_seg, int);
158 int	nlookup_init_at(struct nlookupdata *, struct file **, int,
159 	    const char *, enum uio_seg, int);
160 int	nlookup_init_raw(struct nlookupdata *, const char *, enum uio_seg,
161 	    int, struct ucred *, struct nchandle *);
162 int	nlookup_init_root(struct nlookupdata *, const char *, enum uio_seg,
163 	    int, struct ucred *, struct nchandle *, struct nchandle *);
164 int	nlookup_mp(struct mount *mp, struct nchandle *nch);
165 struct nchandle nlookup_simple(const char *str, enum uio_seg seg,
166 	    int niflags, int *error);
167 void	nlookup_zero(struct nlookupdata *);
168 int	nreadsymlink(struct nlookupdata *nd, struct nchandle *nch,
169 	    struct nlcomponent *nlc);
170 #endif
171 
172 #endif /* !_SYS_NAMEI_H_ */
173