sys/sys/nlookup.h

   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_ */