xref: /dragonfly/sys/sys/nlookup.h (revision 038b596b339f171e591aae50683c27da49cde8d2)
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