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35 #include <sys/caprights.h>
36 #include <sys/filedesc.h>
37 #include <sys/queue.h>
38 #include <sys/_seqc.h>
41 enum nameiop { LOOKUP, CREATE, DELETE, RENAME };
43 struct componentname {
45 * Arguments to lookup.
47 u_int64_t cn_flags; /* flags to namei */
48 struct ucred *cn_cred; /* credentials */
49 enum nameiop cn_nameiop; /* namei operation */
50 int cn_lkflags; /* Lock flags LK_EXCLUSIVE or LK_SHARED */
52 * Shared between lookup and commit routines.
54 char *cn_pnbuf; /* pathname buffer */
55 char *cn_nameptr; /* pointer to looked up name */
56 long cn_namelen; /* length of looked up component */
59 struct nameicap_tracker;
60 TAILQ_HEAD(nameicap_tracker_head, nameicap_tracker);
63 * Encapsulation of namei parameters.
67 * Arguments to namei/lookup.
69 const char *ni_dirp; /* pathname pointer */
70 enum uio_seg ni_segflg; /* location of pathname */
71 cap_rights_t *ni_rightsneeded; /* rights required to look up vnode */
73 * Arguments to lookup.
75 struct vnode *ni_startdir; /* starting directory */
76 struct vnode *ni_rootdir; /* logical root directory */
77 struct vnode *ni_topdir; /* logical top directory */
78 int ni_dirfd; /* starting directory for *at functions */
79 int ni_lcf; /* local call flags */
81 * Results: returned from namei
83 struct filecaps ni_filecaps; /* rights the *at base has */
85 * Results: returned from/manipulated by lookup
87 struct vnode *ni_vp; /* vnode of result */
88 struct vnode *ni_dvp; /* vnode of intermediate directory */
90 * Results: flags returned from namei
94 * Debug for validating API use by the callers.
96 u_short ni_debugflags;
98 * Shared between namei and lookup/commit routines.
100 u_short ni_loopcnt; /* count of symlinks encountered */
101 size_t ni_pathlen; /* remaining chars in path */
102 char *ni_next; /* next location in pathname */
104 * Lookup parameters: this structure describes the subset of
105 * information from the nameidata structure that is passed
106 * through the VOP interface.
108 struct componentname ni_cnd;
109 struct nameicap_tracker_head ni_cap_tracker;
111 * Private helper data for UFS, must be at the end. See
120 enum cache_fpl_status { CACHE_FPL_STATUS_DESTROYED, CACHE_FPL_STATUS_ABORTED,
121 CACHE_FPL_STATUS_PARTIAL, CACHE_FPL_STATUS_HANDLED, CACHE_FPL_STATUS_UNSET };
122 int cache_fplookup(struct nameidata *ndp, enum cache_fpl_status *status,
128 * If modifying the list make sure to check whether NDVALIDATE needs updating.
134 #define NAMEI_DBG_INITED 0x0001
135 #define NAMEI_DBG_CALLED 0x0002
136 #define NAMEI_DBG_HADSTARTDIR 0x0004
139 * namei operational modifier flags, stored in ni_cnd.flags
141 #define NC_NOMAKEENTRY 0x0001 /* name must not be added to cache */
142 #define NC_KEEPPOSENTRY 0x0002 /* don't evict a positive entry */
143 #define NOCACHE NC_NOMAKEENTRY /* for compatibility with older code */
144 #define LOCKLEAF 0x0004 /* lock vnode on return */
145 #define LOCKPARENT 0x0008 /* want parent vnode returned locked */
146 #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */
147 #define FAILIFEXISTS 0x0020 /* return EEXIST if found */
148 #define FOLLOW 0x0040 /* follow symbolic links */
149 #define EMPTYPATH 0x0080 /* Allow empty path for *at */
150 #define LOCKSHARED 0x0100 /* Shared lock leaf */
151 #define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */
152 #define RBENEATH 0x100000000ULL /* No escape, even tmp, from start dir */
153 #define MODMASK 0xf000001ffULL /* mask of operational modifiers */
156 * Namei parameter descriptors.
158 #define RDONLY 0x00000200 /* lookup with read-only semantics */
159 #define ISRESTARTED 0x00000400 /* restarted namei */
160 /* UNUSED 0x00000800 */
161 #define ISWHITEOUT 0x00001000 /* found whiteout */
162 #define DOWHITEOUT 0x00002000 /* do whiteouts */
163 #define WILLBEDIR 0x00004000 /* new files will be dirs; allow trailing / */
164 #define ISOPEN 0x00008000 /* caller is opening; return a real vnode. */
165 #define NOCROSSMOUNT 0x00010000 /* do not cross mount points */
166 #define NOMACCHECK 0x00020000 /* do not perform MAC checks */
167 #define AUDITVNODE1 0x00040000 /* audit the looked up vnode information */
168 #define AUDITVNODE2 0x00080000 /* audit the looked up vnode information */
169 #define NOCAPCHECK 0x00100000 /* do not perform capability checks */
170 #define OPENREAD 0x00200000 /* open for reading */
171 #define OPENWRITE 0x00400000 /* open for writing */
172 #define WANTIOCTLCAPS 0x00800000 /* leave ioctl caps for the caller */
173 /* UNUSED 0x01000000 */
174 #define NOEXECCHECK 0x02000000 /* do not perform exec check on dir */
175 #define MAKEENTRY 0x04000000 /* entry is to be added to name cache */
176 #define ISSYMLINK 0x08000000 /* symlink needs interpretation */
177 #define ISLASTCN 0x10000000 /* this is last component of pathname */
178 #define ISDOTDOT 0x20000000 /* current component name is .. */
179 #define TRAILINGSLASH 0x40000000 /* path ended in a slash */
180 #define PARAMASK 0x7ffffe00 /* mask of parameter descriptors */
183 * Flags which must not be passed in by callers.
185 #define NAMEI_INTERNAL_FLAGS \
186 (NOEXECCHECK | MAKEENTRY | ISSYMLINK | ISLASTCN | ISDOTDOT | \
187 TRAILINGSLASH | ISRESTARTED)
190 * Namei results flags
192 #define NIRES_ABS 0x00000001 /* Path was absolute */
193 #define NIRES_STRICTREL 0x00000002 /* Restricted lookup result */
194 #define NIRES_EMPTYPATH 0x00000004 /* EMPTYPATH used */
197 * Flags in ni_lcf, valid for the duration of the namei call.
199 #define NI_LCF_STRICTRELATIVE 0x0001 /* relative lookup only */
200 #define NI_LCF_CAP_DOTDOT 0x0002 /* ".." in strictrelative case */
203 * Initialization of a nameidata structure.
205 #define NDINIT(ndp, op, flags, segflg, namep) \
206 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, NULL, &cap_no_rights)
207 #define NDINIT_AT(ndp, op, flags, segflg, namep, dirfd) \
208 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, &cap_no_rights)
209 #define NDINIT_ATRIGHTS(ndp, op, flags, segflg, namep, dirfd, rightsp) \
210 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, rightsp)
211 #define NDINIT_ATVP(ndp, op, flags, segflg, namep, vp) \
212 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, vp, &cap_no_rights)
215 * Note the constant pattern may *hide* bugs.
216 * Note also that we enable debug checks for non-TIED KLDs
217 * so that they can run on an INVARIANTS kernel without tripping over
218 * assertions on ni_debugflags state.
220 #if defined(INVARIANTS) || (defined(KLD_MODULE) && !defined(KLD_TIED))
221 #define NDINIT_PREFILL(arg) memset(arg, 0xff, offsetof(struct nameidata, \
223 #define NDINIT_DBG(arg) { (arg)->ni_debugflags = NAMEI_DBG_INITED; }
224 #define NDREINIT_DBG(arg) { \
225 if (((arg)->ni_debugflags & NAMEI_DBG_INITED) == 0) \
226 panic("namei data not inited"); \
227 if (((arg)->ni_debugflags & NAMEI_DBG_HADSTARTDIR) != 0) \
228 panic("NDREINIT on namei data with NAMEI_DBG_HADSTARTDIR"); \
229 (arg)->ni_debugflags = NAMEI_DBG_INITED; \
232 #define NDINIT_PREFILL(arg) do { } while (0)
233 #define NDINIT_DBG(arg) do { } while (0)
234 #define NDREINIT_DBG(arg) do { } while (0)
237 #define NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, startdir, rightsp) \
239 struct nameidata *_ndp = (ndp); \
240 cap_rights_t *_rightsp = (rightsp); \
241 MPASS(_rightsp != NULL); \
242 NDINIT_PREFILL(_ndp); \
244 _ndp->ni_cnd.cn_nameiop = op; \
245 _ndp->ni_cnd.cn_flags = flags; \
246 _ndp->ni_segflg = segflg; \
247 _ndp->ni_dirp = namep; \
248 _ndp->ni_dirfd = dirfd; \
249 _ndp->ni_startdir = startdir; \
250 _ndp->ni_resflags = 0; \
251 filecaps_init(&_ndp->ni_filecaps); \
252 _ndp->ni_rightsneeded = _rightsp; \
255 #define NDREINIT(ndp) do { \
256 struct nameidata *_ndp = (ndp); \
257 NDREINIT_DBG(_ndp); \
258 filecaps_free(&_ndp->ni_filecaps); \
259 _ndp->ni_resflags = 0; \
260 _ndp->ni_startdir = NULL; \
263 #define NDPREINIT(ndp) do { \
264 (ndp)->ni_dvp_seqc = SEQC_MOD; \
265 (ndp)->ni_vp_seqc = SEQC_MOD; \
268 #define NDFREE_IOCTLCAPS(ndp) do { \
269 struct nameidata *_ndp = (ndp); \
270 filecaps_free(&_ndp->ni_filecaps); \
273 #define NDFREE_PNBUF(ndp) do { \
274 struct nameidata *_ndp = (ndp); \
275 MPASS(_ndp->ni_cnd.cn_pnbuf != NULL); \
276 uma_zfree(namei_zone, _ndp->ni_cnd.cn_pnbuf); \
277 _ndp->ni_cnd.cn_pnbuf = NULL; \
280 int namei(struct nameidata *ndp);
281 int vfs_lookup(struct nameidata *ndp);
282 int vfs_relookup(struct vnode *dvp, struct vnode **vpp,
283 struct componentname *cnp, bool refstart);
285 #define namei_setup_rootdir(ndp, cnp, pwd) do { \
286 if (__predict_true((cnp->cn_flags & ISRESTARTED) == 0)) \
287 ndp->ni_rootdir = pwd->pwd_adir; \
289 ndp->ni_rootdir = pwd->pwd_rdir; \
294 * Stats on usefulness of namei caches.
297 long ncs_goodhits; /* hits that we can really use */
298 long ncs_neghits; /* negative hits that we can use */
299 long ncs_badhits; /* hits we must drop */
300 long ncs_falsehits; /* hits with id mismatch */
301 long ncs_miss; /* misses */
302 long ncs_long; /* long names that ignore cache */
303 long ncs_pass2; /* names found with passes == 2 */
304 long ncs_2passes; /* number of times we attempt it */
307 extern struct nchstats nchstats;
309 #endif /* !_SYS_NAMEI_H_ */