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 }; 57 58 struct nameicap_tracker; 59 TAILQ_HEAD(nameicap_tracker_head, nameicap_tracker); 60 61 /* 62 * Encapsulation of namei parameters. 63 */ 64 struct nameidata { 65 /* 66 * Arguments to namei/lookup. 67 */ 68 const char *ni_dirp; /* pathname pointer */ 69 enum uio_seg ni_segflg; /* location of pathname */ 70 cap_rights_t ni_rightsneeded; /* rights required to look up vnode */ 71 /* 72 * Arguments to lookup. 73 */ 74 struct vnode *ni_startdir; /* starting directory */ 75 struct vnode *ni_rootdir; /* logical root directory */ 76 struct vnode *ni_topdir; /* logical top directory */ 77 int ni_dirfd; /* starting directory for *at functions */ 78 int ni_lcf; /* local call flags */ 79 /* 80 * Results: returned from namei 81 */ 82 struct filecaps ni_filecaps; /* rights the *at base has */ 83 /* 84 * Results: returned from/manipulated by lookup 85 */ 86 struct vnode *ni_vp; /* vnode of result */ 87 struct vnode *ni_dvp; /* vnode of intermediate directory */ 88 /* 89 * Shared between namei and lookup/commit routines. 90 */ 91 size_t ni_pathlen; /* remaining chars in path */ 92 char *ni_next; /* next location in pathname */ 93 u_int ni_loopcnt; /* count of symlinks encountered */ 94 /* 95 * Lookup parameters: this structure describes the subset of 96 * information from the nameidata structure that is passed 97 * through the VOP interface. 98 */ 99 struct componentname ni_cnd; 100 struct nameicap_tracker_head ni_cap_tracker; 101 }; 102 103 #ifdef _KERNEL 104 /* 105 * namei operations 106 */ 107 #define LOOKUP 0 /* perform name lookup only */ 108 #define CREATE 1 /* setup for file creation */ 109 #define DELETE 2 /* setup for file deletion */ 110 #define RENAME 3 /* setup for file renaming */ 111 #define OPMASK 3 /* mask for operation */ 112 /* 113 * namei operational modifier flags, stored in ni_cnd.flags 114 */ 115 #define LOCKLEAF 0x0004 /* lock vnode on return */ 116 #define LOCKPARENT 0x0008 /* want parent vnode returned locked */ 117 #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */ 118 #define NOCACHE 0x0020 /* name must not be left in cache */ 119 #define FOLLOW 0x0040 /* follow symbolic links */ 120 #define LOCKSHARED 0x0100 /* Shared lock leaf */ 121 #define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */ 122 #define MODMASK 0x01fc /* mask of operational modifiers */ 123 /* 124 * Namei parameter descriptors. 125 * 126 * SAVENAME may be set by either the callers of namei or by VOP_LOOKUP. 127 * If the caller of namei sets the flag (for example execve wants to 128 * know the name of the program that is being executed), then it must 129 * free the buffer. If VOP_LOOKUP sets the flag, then the buffer must 130 * be freed by either the commit routine or the VOP_ABORT routine. 131 * SAVESTART is set only by the callers of namei. It implies SAVENAME 132 * plus the addition of saving the parent directory that contains the 133 * name in ni_startdir. It allows repeated calls to lookup for the 134 * name being sought. The caller is responsible for releasing the 135 * buffer and for vrele'ing ni_startdir. 136 */ 137 #define RDONLY 0x00000200 /* lookup with read-only semantics */ 138 #define HASBUF 0x00000400 /* has allocated pathname buffer */ 139 #define SAVENAME 0x00000800 /* save pathname buffer */ 140 #define SAVESTART 0x00001000 /* save starting directory */ 141 #define ISDOTDOT 0x00002000 /* current component name is .. */ 142 #define MAKEENTRY 0x00004000 /* entry is to be added to name cache */ 143 #define ISLASTCN 0x00008000 /* this is last component of pathname */ 144 #define ISSYMLINK 0x00010000 /* symlink needs interpretation */ 145 #define ISWHITEOUT 0x00020000 /* found whiteout */ 146 #define DOWHITEOUT 0x00040000 /* do whiteouts */ 147 #define WILLBEDIR 0x00080000 /* new files will be dirs; allow trailing / */ 148 #define ISUNICODE 0x00100000 /* current component name is unicode*/ 149 #define ISOPEN 0x00200000 /* caller is opening; return a real vnode. */ 150 #define NOCROSSMOUNT 0x00400000 /* do not cross mount points */ 151 #define NOMACCHECK 0x00800000 /* do not perform MAC checks */ 152 #define AUDITVNODE1 0x04000000 /* audit the looked up vnode information */ 153 #define AUDITVNODE2 0x08000000 /* audit the looked up vnode information */ 154 #define TRAILINGSLASH 0x10000000 /* path ended in a slash */ 155 #define NOCAPCHECK 0x20000000 /* do not perform capability checks */ 156 #define NOEXECCHECK 0x40000000 /* do not perform exec check on dir */ 157 #define PARAMASK 0x7ffffe00 /* mask of parameter descriptors */ 158 159 /* 160 * Flags in ni_lcf, valid for the duration of the namei call. 161 */ 162 #define NI_LCF_STRICTRELATIVE 0x0001 /* relative lookup only */ 163 #define NI_LCF_CAP_DOTDOT 0x0002 /* ".." in strictrelative case */ 164 165 /* 166 * Initialization of a nameidata structure. 167 */ 168 #define NDINIT(ndp, op, flags, segflg, namep, td) \ 169 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, NULL, 0, td) 170 #define NDINIT_AT(ndp, op, flags, segflg, namep, dirfd, td) \ 171 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, 0, td) 172 #define NDINIT_ATRIGHTS(ndp, op, flags, segflg, namep, dirfd, rightsp, td) \ 173 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, rightsp, td) 174 #define NDINIT_ATVP(ndp, op, flags, segflg, namep, vp, td) \ 175 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, vp, 0, td) 176 177 void NDINIT_ALL(struct nameidata *ndp, u_long op, u_long flags, 178 enum uio_seg segflg, const char *namep, int dirfd, struct vnode *startdir, 179 cap_rights_t *rightsp, struct thread *td); 180 181 #define NDF_NO_DVP_RELE 0x00000001 182 #define NDF_NO_DVP_UNLOCK 0x00000002 183 #define NDF_NO_DVP_PUT 0x00000003 184 #define NDF_NO_VP_RELE 0x00000004 185 #define NDF_NO_VP_UNLOCK 0x00000008 186 #define NDF_NO_VP_PUT 0x0000000c 187 #define NDF_NO_STARTDIR_RELE 0x00000010 188 #define NDF_NO_FREE_PNBUF 0x00000020 189 #define NDF_ONLY_PNBUF (~NDF_NO_FREE_PNBUF) 190 191 void NDFREE(struct nameidata *, const u_int); 192 193 int namei(struct nameidata *ndp); 194 int lookup(struct nameidata *ndp); 195 int relookup(struct vnode *dvp, struct vnode **vpp, 196 struct componentname *cnp); 197 #endif 198 199 /* 200 * Stats on usefulness of namei caches. 201 */ 202 struct nchstats { 203 long ncs_goodhits; /* hits that we can really use */ 204 long ncs_neghits; /* negative hits that we can use */ 205 long ncs_badhits; /* hits we must drop */ 206 long ncs_falsehits; /* hits with id mismatch */ 207 long ncs_miss; /* misses */ 208 long ncs_long; /* long names that ignore cache */ 209 long ncs_pass2; /* names found with passes == 2 */ 210 long ncs_2passes; /* number of times we attempt it */ 211 }; 212 213 extern struct nchstats nchstats; 214 215 #endif /* !_SYS_NAMEI_H_ */ 216