/*- * SPDX-License-Identifier: BSD-3-Clause * * 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 8.5 (Berkeley) 1/9/95 * $FreeBSD$ */ #ifndef _SYS_NAMEI_H_ #define _SYS_NAMEI_H_ #include #include #include #include enum nameiop { LOOKUP, CREATE, DELETE, RENAME }; struct componentname { /* * Arguments to lookup. */ u_int64_t cn_origflags; /* flags to namei */ u_int64_t cn_flags; /* flags to namei */ struct thread *cn_thread;/* thread requesting lookup */ struct ucred *cn_cred; /* credentials */ enum nameiop cn_nameiop; /* namei operation */ int cn_lkflags; /* Lock flags LK_EXCLUSIVE or LK_SHARED */ /* * Shared between lookup and commit routines. */ char *cn_pnbuf; /* pathname buffer */ char *cn_nameptr; /* pointer to looked up name */ long cn_namelen; /* length of looked up component */ }; struct nameicap_tracker; TAILQ_HEAD(nameicap_tracker_head, nameicap_tracker); /* * Encapsulation of namei parameters. */ struct nameidata { /* * Arguments to namei/lookup. */ const char *ni_dirp; /* pathname pointer */ enum uio_seg ni_segflg; /* location of pathname */ cap_rights_t *ni_rightsneeded; /* rights required to look up vnode */ /* * Arguments to lookup. */ struct vnode *ni_startdir; /* starting directory */ struct vnode *ni_rootdir; /* logical root directory */ struct vnode *ni_topdir; /* logical top directory */ int ni_dirfd; /* starting directory for *at functions */ int ni_lcf; /* local call flags */ /* * Results: returned from namei */ struct filecaps ni_filecaps; /* rights the *at base has */ /* * Results: returned from/manipulated by lookup */ struct vnode *ni_vp; /* vnode of result */ struct vnode *ni_dvp; /* vnode of intermediate directory */ /* * Results: flags returned from namei */ u_int ni_resflags; /* * Debug for validating API use by the callers. */ u_short ni_debugflags; /* * Shared between namei and lookup/commit routines. */ u_short ni_loopcnt; /* count of symlinks encountered */ size_t ni_pathlen; /* remaining chars in path */ char *ni_next; /* next location in pathname */ /* * Lookup parameters: this structure describes the subset of * information from the nameidata structure that is passed * through the VOP interface. */ struct componentname ni_cnd; struct nameicap_tracker_head ni_cap_tracker; struct vnode *ni_beneath_latch; }; #ifdef _KERNEL enum cache_fpl_status { CACHE_FPL_STATUS_ABORTED, CACHE_FPL_STATUS_PARTIAL, CACHE_FPL_STATUS_HANDLED, CACHE_FPL_STATUS_UNSET }; int cache_fplookup(struct nameidata *ndp, enum cache_fpl_status *status, struct pwd **pwdp); /* * Flags for namei. * * If modifying the list make sure to check whether NDVALIDATE needs updating. */ /* * Debug. */ #define NAMEI_DBG_INITED 0x0001 #define NAMEI_DBG_CALLED 0x0002 #define NAMEI_DBG_HADSTARTDIR 0x0004 /* * namei operational modifier flags, stored in ni_cnd.flags */ #define NC_NOMAKEENTRY 0x0001 /* name must not be added to cache */ #define NC_KEEPPOSENTRY 0x0002 /* don't evict a positive entry */ #define NOCACHE NC_NOMAKEENTRY /* for compatibility with older code */ #define LOCKLEAF 0x0004 /* lock vnode on return */ #define LOCKPARENT 0x0008 /* want parent vnode returned locked */ #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */ #define FAILIFEXISTS 0x0020 /* return EEXIST if found */ #define FOLLOW 0x0040 /* follow symbolic links */ #define BENEATH 0x0080 /* No escape from the start dir */ #define LOCKSHARED 0x0100 /* Shared lock leaf */ #define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */ #define RBENEATH 0x100000000ULL /* No escape, even tmp, from start dir */ #define MODMASK 0xf000001ffULL /* 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 RDONLY 0x00000200 /* lookup with read-only semantics */ #define SAVENAME 0x00000400 /* save pathname buffer */ #define SAVESTART 0x00000800 /* save starting directory */ #define ISWHITEOUT 0x00001000 /* found whiteout */ #define DOWHITEOUT 0x00002000 /* do whiteouts */ #define WILLBEDIR 0x00004000 /* new files will be dirs; allow trailing / */ #define ISOPEN 0x00008000 /* caller is opening; return a real vnode. */ #define NOCROSSMOUNT 0x00010000 /* do not cross mount points */ #define NOMACCHECK 0x00020000 /* do not perform MAC checks */ #define AUDITVNODE1 0x00040000 /* audit the looked up vnode information */ #define AUDITVNODE2 0x00080000 /* audit the looked up vnode information */ #define NOCAPCHECK 0x00100000 /* do not perform capability checks */ /* UNUSED 0x00200000 */ /* UNUSED 0x00400000 */ /* UNUSED 0x00800000 */ #define HASBUF 0x01000000 /* has allocated pathname buffer */ #define NOEXECCHECK 0x02000000 /* do not perform exec check on dir */ #define MAKEENTRY 0x04000000 /* entry is to be added to name cache */ #define ISSYMLINK 0x08000000 /* symlink needs interpretation */ #define ISLASTCN 0x10000000 /* this is last component of pathname */ #define ISDOTDOT 0x20000000 /* current component name is .. */ #define TRAILINGSLASH 0x40000000 /* path ended in a slash */ #define PARAMASK 0x7ffffe00 /* mask of parameter descriptors */ /* * Flags which must not be passed in by callers. */ #define NAMEI_INTERNAL_FLAGS \ (HASBUF | NOEXECCHECK | MAKEENTRY | ISSYMLINK | ISLASTCN | ISDOTDOT | \ TRAILINGSLASH) /* * Namei results flags */ #define NIRES_ABS 0x00000001 /* Path was absolute */ #define NIRES_STRICTREL 0x00000002 /* Restricted lookup result */ /* * Flags in ni_lcf, valid for the duration of the namei call. */ #define NI_LCF_STRICTRELATIVE 0x0001 /* relative lookup only */ #define NI_LCF_CAP_DOTDOT 0x0002 /* ".." in strictrelative case */ #define NI_LCF_BENEATH_ABS 0x0004 /* BENEATH with absolute path */ #define NI_LCF_BENEATH_LATCHED 0x0008 /* BENEATH_ABS traversed starting dir */ #define NI_LCF_LATCH 0x0010 /* ni_beneath_latch valid */ /* * Initialization of a nameidata structure. */ #define NDINIT(ndp, op, flags, segflg, namep, td) \ NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, NULL, &cap_no_rights, td) #define NDINIT_AT(ndp, op, flags, segflg, namep, dirfd, td) \ NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, &cap_no_rights, td) #define NDINIT_ATRIGHTS(ndp, op, flags, segflg, namep, dirfd, rightsp, td) \ NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, rightsp, td) #define NDINIT_ATVP(ndp, op, flags, segflg, namep, vp, td) \ NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, vp, &cap_no_rights, td) /* * Note the constant pattern may *hide* bugs. */ #ifdef INVARIANTS #define NDINIT_PREFILL(arg) memset(arg, 0xff, sizeof(*arg)) #define NDINIT_DBG(arg) { (arg)->ni_debugflags = NAMEI_DBG_INITED; } #define NDREINIT_DBG(arg) { \ if (((arg)->ni_debugflags & NAMEI_DBG_INITED) == 0) \ panic("namei data not inited"); \ if (((arg)->ni_debugflags & NAMEI_DBG_HADSTARTDIR) != 0) \ panic("NDREINIT on namei data with NAMEI_DBG_HADSTARTDIR"); \ (arg)->ni_debugflags = NAMEI_DBG_INITED; \ } #else #define NDINIT_PREFILL(arg) do { } while (0) #define NDINIT_DBG(arg) do { } while (0) #define NDREINIT_DBG(arg) do { } while (0) #endif #define NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, startdir, rightsp, td) \ do { \ struct nameidata *_ndp = (ndp); \ cap_rights_t *_rightsp = (rightsp); \ MPASS(_rightsp != NULL); \ NDINIT_PREFILL(_ndp); \ NDINIT_DBG(_ndp); \ _ndp->ni_cnd.cn_nameiop = op; \ _ndp->ni_cnd.cn_flags = flags; \ _ndp->ni_segflg = segflg; \ _ndp->ni_dirp = namep; \ _ndp->ni_dirfd = dirfd; \ _ndp->ni_startdir = startdir; \ _ndp->ni_resflags = 0; \ filecaps_init(&_ndp->ni_filecaps); \ _ndp->ni_cnd.cn_thread = td; \ _ndp->ni_rightsneeded = _rightsp; \ } while (0) #define NDREINIT(ndp) do { \ struct nameidata *_ndp = (ndp); \ NDREINIT_DBG(_ndp); \ _ndp->ni_resflags = 0; \ _ndp->ni_startdir = NULL; \ } while (0) #define NDF_NO_DVP_RELE 0x00000001 #define NDF_NO_DVP_UNLOCK 0x00000002 #define NDF_NO_DVP_PUT 0x00000003 #define NDF_NO_VP_RELE 0x00000004 #define NDF_NO_VP_UNLOCK 0x00000008 #define NDF_NO_VP_PUT 0x0000000c #define NDF_NO_STARTDIR_RELE 0x00000010 #define NDF_NO_FREE_PNBUF 0x00000020 #define NDF_ONLY_PNBUF (~NDF_NO_FREE_PNBUF) void NDFREE_PNBUF(struct nameidata *); void NDFREE(struct nameidata *, const u_int); #define NDFREE(ndp, flags) do { \ struct nameidata *_ndp = (ndp); \ if (__builtin_constant_p(flags) && flags == NDF_ONLY_PNBUF) \ NDFREE_PNBUF(_ndp); \ else \ NDFREE(_ndp, flags); \ } while (0) #ifdef INVARIANTS void NDFREE_NOTHING(struct nameidata *); void NDVALIDATE(struct nameidata *); #else #define NDFREE_NOTHING(ndp) do { } while (0) #define NDVALIDATE(ndp) do { } while (0) #endif int namei(struct nameidata *ndp); int lookup(struct nameidata *ndp); int relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp); #endif /* * Stats on usefulness of namei caches. */ struct nchstats { long ncs_goodhits; /* hits that we can really use */ long ncs_neghits; /* negative hits that we can use */ long ncs_badhits; /* hits we must drop */ long ncs_falsehits; /* hits with id mismatch */ long ncs_miss; /* misses */ long ncs_long; /* long names that ignore cache */ long ncs_pass2; /* names found with passes == 2 */ long ncs_2passes; /* number of times we attempt it */ }; extern struct nchstats nchstats; #endif /* !_SYS_NAMEI_H_ */