1 /*- 2 * Copyright (c) 1985, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)namei.h 8.5 (Berkeley) 1/9/95 30 * $FreeBSD$ 31 */ 32 33 #ifndef _SYS_NAMEI_H_ 34 #define _SYS_NAMEI_H_ 35 36 #include <sys/caprights.h> 37 #include <sys/filedesc.h> 38 #include <sys/queue.h> 39 #include <sys/uio.h> 40 41 struct componentname { 42 /* 43 * Arguments to lookup. 44 */ 45 u_long cn_nameiop; /* namei operation */ 46 u_int64_t cn_flags; /* flags to namei */ 47 struct thread *cn_thread;/* thread requesting lookup */ 48 struct ucred *cn_cred; /* credentials */ 49 int cn_lkflags; /* Lock flags LK_EXCLUSIVE or LK_SHARED */ 50 /* 51 * Shared between lookup and commit routines. 52 */ 53 char *cn_pnbuf; /* pathname buffer */ 54 char *cn_nameptr; /* pointer to looked up name */ 55 long cn_namelen; /* length of looked up component */ 56 long cn_consume; /* chars to consume in lookup() */ 57 }; 58 59 /* 60 * Encapsulation of namei parameters. 61 */ 62 struct nameidata { 63 /* 64 * Arguments to namei/lookup. 65 */ 66 const char *ni_dirp; /* pathname pointer */ 67 enum uio_seg ni_segflg; /* location of pathname */ 68 cap_rights_t ni_rightsneeded; /* rights required to look up vnode */ 69 /* 70 * Arguments to lookup. 71 */ 72 struct vnode *ni_startdir; /* starting directory */ 73 struct vnode *ni_rootdir; /* logical root directory */ 74 struct vnode *ni_topdir; /* logical top directory */ 75 int ni_dirfd; /* starting directory for *at functions */ 76 int ni_strictrelative; /* relative lookup only; no '..' */ 77 /* 78 * Results: returned from namei 79 */ 80 struct filecaps ni_filecaps; /* rights the *at base has */ 81 /* 82 * Results: returned from/manipulated by lookup 83 */ 84 struct vnode *ni_vp; /* vnode of result */ 85 struct vnode *ni_dvp; /* vnode of intermediate directory */ 86 /* 87 * Shared between namei and lookup/commit routines. 88 */ 89 size_t ni_pathlen; /* remaining chars in path */ 90 char *ni_next; /* next location in pathname */ 91 u_int ni_loopcnt; /* count of symlinks encountered */ 92 /* 93 * Lookup parameters: this structure describes the subset of 94 * information from the nameidata structure that is passed 95 * through the VOP interface. 96 */ 97 struct componentname ni_cnd; 98 }; 99 100 #ifdef _KERNEL 101 /* 102 * namei operations 103 */ 104 #define LOOKUP 0 /* perform name lookup only */ 105 #define CREATE 1 /* setup for file creation */ 106 #define DELETE 2 /* setup for file deletion */ 107 #define RENAME 3 /* setup for file renaming */ 108 #define OPMASK 3 /* mask for operation */ 109 /* 110 * namei operational modifier flags, stored in ni_cnd.flags 111 */ 112 #define LOCKLEAF 0x0004 /* lock vnode on return */ 113 #define LOCKPARENT 0x0008 /* want parent vnode returned locked */ 114 #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */ 115 #define NOCACHE 0x0020 /* name must not be left in cache */ 116 #define FOLLOW 0x0040 /* follow symbolic links */ 117 #define LOCKSHARED 0x0100 /* Shared lock leaf */ 118 #define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */ 119 #define MODMASK 0x01fc /* mask of operational modifiers */ 120 /* 121 * Namei parameter descriptors. 122 * 123 * SAVENAME may be set by either the callers of namei or by VOP_LOOKUP. 124 * If the caller of namei sets the flag (for example execve wants to 125 * know the name of the program that is being executed), then it must 126 * free the buffer. If VOP_LOOKUP sets the flag, then the buffer must 127 * be freed by either the commit routine or the VOP_ABORT routine. 128 * SAVESTART is set only by the callers of namei. It implies SAVENAME 129 * plus the addition of saving the parent directory that contains the 130 * name in ni_startdir. It allows repeated calls to lookup for the 131 * name being sought. The caller is responsible for releasing the 132 * buffer and for vrele'ing ni_startdir. 133 */ 134 #define RDONLY 0x00000200 /* lookup with read-only semantics */ 135 #define HASBUF 0x00000400 /* has allocated pathname buffer */ 136 #define SAVENAME 0x00000800 /* save pathname buffer */ 137 #define SAVESTART 0x00001000 /* save starting directory */ 138 #define ISDOTDOT 0x00002000 /* current component name is .. */ 139 #define MAKEENTRY 0x00004000 /* entry is to be added to name cache */ 140 #define ISLASTCN 0x00008000 /* this is last component of pathname */ 141 #define ISSYMLINK 0x00010000 /* symlink needs interpretation */ 142 #define ISWHITEOUT 0x00020000 /* found whiteout */ 143 #define DOWHITEOUT 0x00040000 /* do whiteouts */ 144 #define WILLBEDIR 0x00080000 /* new files will be dirs; allow trailing / */ 145 #define ISUNICODE 0x00100000 /* current component name is unicode*/ 146 #define ISOPEN 0x00200000 /* caller is opening; return a real vnode. */ 147 #define NOCROSSMOUNT 0x00400000 /* do not cross mount points */ 148 #define NOMACCHECK 0x00800000 /* do not perform MAC checks */ 149 #define AUDITVNODE1 0x04000000 /* audit the looked up vnode information */ 150 #define AUDITVNODE2 0x08000000 /* audit the looked up vnode information */ 151 #define TRAILINGSLASH 0x10000000 /* path ended in a slash */ 152 #define NOCAPCHECK 0x20000000 /* do not perform capability checks */ 153 #define PARAMASK 0x3ffffe00 /* mask of parameter descriptors */ 154 155 /* 156 * Initialization of a nameidata structure. 157 */ 158 #define NDINIT(ndp, op, flags, segflg, namep, td) \ 159 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, NULL, 0, td) 160 #define NDINIT_AT(ndp, op, flags, segflg, namep, dirfd, td) \ 161 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, 0, td) 162 #define NDINIT_ATRIGHTS(ndp, op, flags, segflg, namep, dirfd, rightsp, td) \ 163 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, rightsp, td) 164 #define NDINIT_ATVP(ndp, op, flags, segflg, namep, vp, td) \ 165 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, vp, 0, td) 166 167 void NDINIT_ALL(struct nameidata *ndp, u_long op, u_long flags, 168 enum uio_seg segflg, const char *namep, int dirfd, struct vnode *startdir, 169 cap_rights_t *rightsp, struct thread *td); 170 171 #define NDF_NO_DVP_RELE 0x00000001 172 #define NDF_NO_DVP_UNLOCK 0x00000002 173 #define NDF_NO_DVP_PUT 0x00000003 174 #define NDF_NO_VP_RELE 0x00000004 175 #define NDF_NO_VP_UNLOCK 0x00000008 176 #define NDF_NO_VP_PUT 0x0000000c 177 #define NDF_NO_STARTDIR_RELE 0x00000010 178 #define NDF_NO_FREE_PNBUF 0x00000020 179 #define NDF_ONLY_PNBUF (~NDF_NO_FREE_PNBUF) 180 181 void NDFREE(struct nameidata *, const u_int); 182 183 int namei(struct nameidata *ndp); 184 int lookup(struct nameidata *ndp); 185 int relookup(struct vnode *dvp, struct vnode **vpp, 186 struct componentname *cnp); 187 #endif 188 189 /* 190 * Stats on usefulness of namei caches. 191 */ 192 struct nchstats { 193 long ncs_goodhits; /* hits that we can really use */ 194 long ncs_neghits; /* negative hits that we can use */ 195 long ncs_badhits; /* hits we must drop */ 196 long ncs_falsehits; /* hits with id mismatch */ 197 long ncs_miss; /* misses */ 198 long ncs_long; /* long names that ignore cache */ 199 long ncs_pass2; /* names found with passes == 2 */ 200 long ncs_2passes; /* number of times we attempt it */ 201 }; 202 203 extern struct nchstats nchstats; 204 205 #endif /* !_SYS_NAMEI_H_ */ 206