/* $OpenBSD: namei.h,v 1.51 2026/03/08 16:41:19 deraadt Exp $ */ /* $NetBSD: namei.h,v 1.11 1996/02/09 18:25:20 christos Exp $ */ /* * Copyright (c) 1985, 1989, 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)namei.h 8.4 (Berkeley) 8/20/94 */ #ifndef _SYS_NAMEI_H_ #define _SYS_NAMEI_H_ #include <sys/queue.h> #include <sys/tree.h> #include <sys/uio.h> struct unveil; /* * Encapsulation of namei parameters. */ struct nameidata { /* * Arguments to namei/lookup. */ const char *ni_dirp; /* pathname pointer */ int ni_dirfd; /* dirfd from *at() functions */ enum uio_seg ni_segflg; /* location of pathname */ /* u_long ni_nameiop; namei operation */ /* u_long ni_flags; flags to namei */ /* struct proc *ni_proc; process requesting lookup */ /* * Arguments to lookup. */ /* struct ucred *ni_cred; credentials */ struct vnode *ni_startdir; /* starting directory */ struct vnode *ni_rootdir; /* logical root directory */ uint64_t ni_pledge; /* expected pledge for namei */ u_char ni_unveil; /* required unveil flags for namei */ /* * Results: returned from/manipulated by lookup */ struct vnode *ni_vp; /* vnode of result */ struct vnode *ni_dvp; /* vnode of intermediate directory */ /* * Shared between namei and lookup/commit routines. */ size_t ni_pathlen; /* remaining chars in path */ char *ni_next; /* next location in pathname */ u_long ni_loopcnt; /* count of symlinks encountered */ struct unveil *ni_unveil_match; /* last matching unveil component */ /* * Lookup parameters: this structure describes the subset of * information from the nameidata structure that is passed * through the VOP interface. */ struct componentname { /* * Arguments to lookup. */ u_long cn_nameiop; /* namei operation */ u_long cn_flags; /* flags to namei */ struct proc *cn_proc; /* process requesting lookup */ struct ucred *cn_cred; /* credentials */ /* * Shared between lookup and commit routines. */ char *cn_pnbuf; /* pathname buffer */ char *cn_rpbuf; /* realpath buffer */ size_t cn_rpi; /* realpath index */ char *cn_nameptr; /* pointer to looked up name */ long cn_namelen; /* length of looked up component */ long cn_consume; /* chars to consume in lookup() */ } ni_cnd; }; #ifdef _KERNEL /* * namei operations */ #define LOOKUP 0 /* perform name lookup only */ #define CREATE 1 /* setup for file creation */ #define DELETE 2 /* setup for file deletion */ #define RENAME 3 /* setup for file renaming */ #define OPMASK 3 /* mask for operation */ /* * namei operational modifier flags, stored in ni_cnd.flags */ #define LOCKLEAF 0x0004 /* lock inode on return */ #define LOCKPARENT 0x0008 /* want parent vnode returned locked */ #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */ #define NOCACHE 0x0020 /* name must not be left in cache */ #define FOLLOW 0x0040 /* follow symbolic links */ #define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */ #define MODMASK 0x00fc /* mask of operational modifiers */ /* * Namei parameter descriptors. * * SAVENAME may be set by either the callers of namei or by VOP_LOOKUP. * If the caller of namei sets the flag (for example execve wants to * know the name of the program that is being executed), then it must * free the buffer. If VOP_LOOKUP sets the flag, then the buffer must * be freed by either the commit routine or the VOP_ABORT routine. * SAVESTART is set only by the callers of namei. It implies SAVENAME * plus the addition of saving the parent directory that contains the * name in ni_startdir. It allows repeated calls to lookup for the * name being sought. The caller is responsible for releasing the * buffer and for vrele'ing ni_startdir. */ #define NOCROSSMOUNT 0x000100 /* do not cross mount points */ #define RDONLY 0x000200 /* lookup with read-only semantics */ #define HASBUF 0x000400 /* has allocated pathname buffer */ #define SAVENAME 0x000800 /* save pathname buffer */ #define SAVESTART 0x001000 /* save starting directory */ #define ISDOTDOT 0x002000 /* current component name is .. */ #define MAKEENTRY 0x004000 /* entry is to be added to name cache */ #define ISLASTCN 0x008000 /* this is last component of pathname */ #define ISSYMLINK 0x010000 /* symlink needs interpretation */ #define REALPATH 0x020000 /* save pathname buffer for realpath */ #define REQUIREDIR 0x080000 /* must be a directory */ #define STRIPSLASHES 0x100000 /* strip trailing slashes */ #define PDIRUNLOCK 0x200000 /* vfs_lookup() unlocked parent dir */ #define BYPASSUNVEIL 0x400000 /* bypass pledgepath check */ #define KERNELPATH 0x800000 /* access file as kernel, not process */ /* * Initialization of an nameidata structure. */ void ndinitat(struct nameidata *ndp, u_long op, u_long flags, enum uio_seg segflg, int dirfd, const char *namep, struct proc *p); #define NDINITAT(ndp, op, flags, segflg, dirfd, namep, p) \ ndinitat(ndp, op, flags, segflg, dirfd, namep, p) #define NDINIT(ndp, op, flags, segflp, namep, p) \ ndinitat(ndp, op, flags, segflp, AT_FDCWD, namep, p) /* Defined for users of NDINIT(). */ #define AT_FDCWD -100 #endif /* * This structure describes the elements in the cache of recent * names looked up by namei. */ #define NAMECACHE_MAXLEN 31 /* maximum name segment length we bother with */ struct namecache { TAILQ_ENTRY(namecache) nc_lru; /* Regular Entry LRU chain */ TAILQ_ENTRY(namecache) nc_neg; /* Negative Entry LRU chain */ RBT_ENTRY(namecache) n_rbcache; /* Namecache rb tree from vnode */ TAILQ_ENTRY(namecache) nc_me; /* ncp's referring to me */ struct vnode *nc_dvp; /* vnode of parent of name */ u_long nc_dvpid; /* capability number of nc_dvp */ struct vnode *nc_vp; /* vnode the name refers to */ u_long nc_vpid; /* capability number of nc_vp */ char nc_nlen; /* length of name */ char nc_name[NAMECACHE_MAXLEN]; /* segment name */ }; #ifdef _KERNEL struct namecache_rb_cache; int namei(struct nameidata *ndp); int vfs_lookup(struct nameidata *ndp); int vfs_relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp); void cache_tree_init(struct namecache_rb_cache *); void cache_purge(struct vnode *); int cache_lookup(struct vnode *, struct vnode **, struct componentname *); void cache_enter(struct vnode *, struct vnode *, struct componentname *); int cache_revlookup(struct vnode *, struct vnode **, char **, char *); void nchinit(void); struct mount; void cache_purgevfs(struct mount *); int unveil_add(struct proc *, struct nameidata *, const char *); void unveil_removevnode(struct vnode *); ssize_t unveil_find_cover(struct vnode *, struct proc *); struct unveil *unveil_lookup(struct vnode *, struct process *, ssize_t *); void unveil_start_relative(struct proc *, struct nameidata *, struct vnode *); void unveil_check_component(struct proc *, struct nameidata *, struct vnode *); int unveil_check_final(struct proc *, struct nameidata *); extern struct pool namei_pool; #endif /* * Stats on usefulness of namei caches. */ struct nchstats { u_int64_t ncs_goodhits; /* hits that we can really use */ u_int64_t ncs_neghits; /* negative hits that we can use */ u_int64_t ncs_badhits; /* hits we must drop */ u_int64_t ncs_falsehits; /* hits with id mismatch */ u_int64_t ncs_miss; /* misses */ u_int64_t ncs_long; /* long names that ignore cache */ u_int64_t ncs_pass2; /* names found with passes == 2 */ u_int64_t ncs_2passes; /* number of times we attempt it */ u_int64_t ncs_revhits; /* reverse-cache hits */ u_int64_t ncs_revmiss; /* reverse-cache misses */ u_int64_t ncs_dothits; /* hits on '.' lookups */ u_int64_t ncs_dotdothits; /* hits on '..' lookups */ }; /* These sysctl names are only really used by sysctl(8) */ #define KERN_NCHSTATS_GOODHITS 1 #define KERN_NCHSTATS_NEGHITS 2 #define KERN_NCHSTATS_BADHITS 3 #define KERN_NCHSTATS_FALSEHITS 4 #define KERN_NCHSTATS_MISS 5 #define KERN_NCHSTATS_LONG 6 #define KERN_NCHSTATS_PASS2 7 #define KERN_NCHSTATS_2PASSES 8 #define KERN_NCHSTATS_REVHITS 9 #define KERN_NCHSTATS_REVMISS 10 #define KERN_NCHSTATS_DOTHITS 11 #define KERN_NCHSTATS_DOTDOTHITS 12 #define KERN_NCHSTATS_MAXID 13 #define CTL_KERN_NCHSTATS_NAMES { \ { 0, 0 }, \ { "good_hits", CTLTYPE_QUAD }, \ { "negative_hits", CTLTYPE_QUAD }, \ { "bad_hits", CTLTYPE_QUAD }, \ { "false_hits", CTLTYPE_QUAD }, \ { "misses", CTLTYPE_QUAD }, \ { "long_names", CTLTYPE_QUAD }, \ { "pass2", CTLTYPE_QUAD }, \ { "2passes", CTLTYPE_QUAD }, \ { "ncs_revhits", CTLTYPE_QUAD }, \ { "ncs_revmiss", CTLTYPE_QUAD }, \ { "ncs_dothits", CTLTYPE_QUAD }, \ { "nch_dotdothits", CTLTYPE_QUAD }, \ } /* Unveil flags for namei */ #define UNVEIL_READ 0x01 #define UNVEIL_WRITE 0x02 #define UNVEIL_CREATE 0x04 #define UNVEIL_EXEC 0x08 #define UNVEIL_USERSET 0x10 #define UNVEIL_PLEDGEOPEN 0X20 #define UNVEIL_MASK 0x0f #endif /* !_SYS_NAMEI_H_ */
