1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
27 /* All Rights Reserved */
28
29 /*
30 * Copyright (c) 2013, OmniTI Computer Consulting, Inc. All rights reserved.
31 */
32 /*
33 * Portions of this source code were derived from Berkeley 4.3 BSD
34 * under license from the Regents of the University of California.
35 */
36
37 #include <sys/param.h>
38 #include <sys/isa_defs.h>
39 #include <sys/types.h>
40 #include <sys/sysmacros.h>
41 #include <sys/user.h>
42 #include <sys/systm.h>
43 #include <sys/errno.h>
44 #include <sys/fcntl.h>
45 #include <sys/stat.h>
46 #include <sys/vnode.h>
47 #include <sys/vfs.h>
48 #include <sys/file.h>
49 #include <sys/mode.h>
50 #include <sys/uio.h>
51 #include <sys/debug.h>
52 #include <c2/audit.h>
53
54 /*
55 * Common code for openat(). Check permissions, allocate an open
56 * file structure, and call the device open routine (if any).
57 */
58
59 static int
60 copen(int startfd, char *fname, int filemode, int createmode)
61 {
62 struct pathname pn;
63 vnode_t *vp, *sdvp;
64 file_t *fp, *startfp;
65 enum vtype type;
66 int error;
67 int fd, dupfd;
68 vnode_t *startvp;
69 proc_t *p = curproc;
70 uio_seg_t seg = UIO_USERSPACE;
71 char *open_filename = fname;
72 uint32_t auditing = AU_AUDITING();
73 char startchar;
74
75 if (filemode & (FSEARCH|FEXEC)) {
76 /*
77 * Must be one or the other and neither FREAD nor FWRITE
78 * Must not be any of FAPPEND FCREAT FTRUNC FXATTR FXATTRDIROPEN
79 * XXX: Should these just be silently ignored?
80 */
81 if ((filemode & (FREAD|FWRITE)) ||
82 (filemode & (FSEARCH|FEXEC)) == (FSEARCH|FEXEC) ||
83 (filemode & (FAPPEND|FCREAT|FTRUNC|FXATTR|FXATTRDIROPEN)))
84 return (set_errno(EINVAL));
85 }
86
87 if (startfd == AT_FDCWD) {
88 /*
89 * Regular open()
90 */
91 startvp = NULL;
92 } else {
93 /*
94 * We're here via openat()
95 */
96 if (copyin(fname, &startchar, sizeof (char)))
97 return (set_errno(EFAULT));
98
99 /*
100 * if startchar is / then startfd is ignored
101 */
102 if (startchar == '/')
103 startvp = NULL;
104 else {
105 if ((startfp = getf(startfd)) == NULL)
106 return (set_errno(EBADF));
107 startvp = startfp->f_vnode;
108 VN_HOLD(startvp);
109 releasef(startfd);
110 }
111 }
112
113 /*
114 * Handle __openattrdirat() requests
115 */
116 if (filemode & FXATTRDIROPEN) {
117 if (auditing && startvp != NULL)
118 audit_setfsat_path(1);
119 if (error = lookupnameat(fname, seg, FOLLOW,
120 NULLVPP, &vp, startvp))
121 return (set_errno(error));
122 if (startvp != NULL)
123 VN_RELE(startvp);
124
125 startvp = vp;
126 }
127
128 /*
129 * Do we need to go into extended attribute space?
130 */
131 if (filemode & FXATTR) {
132 if (startfd == AT_FDCWD) {
133 if (copyin(fname, &startchar, sizeof (char)))
134 return (set_errno(EFAULT));
135
136 /*
137 * If startchar == '/' then no extended attributes
138 * are looked up.
139 */
140 if (startchar == '/') {
141 startvp = NULL;
142 } else {
143 mutex_enter(&p->p_lock);
144 startvp = PTOU(p)->u_cdir;
145 VN_HOLD(startvp);
146 mutex_exit(&p->p_lock);
147 }
148 }
149
150 /*
151 * Make sure we have a valid extended attribute request.
152 * We must either have a real fd or AT_FDCWD and a relative
153 * pathname.
154 */
155 if (startvp == NULL) {
156 goto noxattr;
157 }
158 }
159
160 if (filemode & (FXATTR|FXATTRDIROPEN)) {
161 vattr_t vattr;
162
163 if (error = pn_get(fname, UIO_USERSPACE, &pn)) {
164 goto out;
165 }
166
167 /*
168 * In order to access hidden attribute directory the
169 * user must be able to stat() the file
170 */
171 vattr.va_mask = AT_ALL;
172 if (error = VOP_GETATTR(startvp, &vattr, 0, CRED(), NULL)) {
173 pn_free(&pn);
174 goto out;
175 }
176
177 if ((startvp->v_vfsp->vfs_flag & VFS_XATTR) != 0 ||
178 vfs_has_feature(startvp->v_vfsp, VFSFT_SYSATTR_VIEWS)) {
179 error = VOP_LOOKUP(startvp, "", &sdvp, &pn,
180 (filemode & FXATTRDIROPEN) ? LOOKUP_XATTR :
181 LOOKUP_XATTR|CREATE_XATTR_DIR, rootvp, CRED(),
182 NULL, NULL, NULL);
183 } else {
184 error = EINVAL;
185 }
186
187 /*
188 * For __openattrdirat() use "." as filename to open
189 * as part of vn_openat()
190 */
191 if (error == 0 && (filemode & FXATTRDIROPEN)) {
192 open_filename = ".";
193 seg = UIO_SYSSPACE;
194 }
195
196 pn_free(&pn);
197 if (error != 0)
198 goto out;
199
200 VN_RELE(startvp);
201 startvp = sdvp;
202 }
203
204 noxattr:
205 if ((filemode & (FREAD|FWRITE|FSEARCH|FEXEC|FXATTRDIROPEN)) != 0) {
206 if ((filemode & (FNONBLOCK|FNDELAY)) == (FNONBLOCK|FNDELAY))
207 filemode &= ~FNDELAY;
208 error = falloc((vnode_t *)NULL, filemode, &fp, &fd);
209 if (error == 0) {
210 if (auditing && startvp != NULL)
211 audit_setfsat_path(1);
212 /*
213 * Last arg is a don't-care term if
214 * !(filemode & FCREAT).
215 */
216 error = vn_openat(open_filename, seg, filemode,
217 (int)(createmode & MODEMASK),
218 &vp, CRCREAT, PTOU(curproc)->u_cmask,
219 startvp, fd);
220
221 if (startvp != NULL)
222 VN_RELE(startvp);
223 if (error == 0) {
224 if ((vp->v_flag & VDUP) == 0) {
225 fp->f_vnode = vp;
226 mutex_exit(&fp->f_tlock);
227 /*
228 * We must now fill in the slot
229 * falloc reserved.
230 */
231 setf(fd, fp);
232 if ((filemode & FCLOEXEC) != 0) {
233 f_setfd(fd, FD_CLOEXEC);
234 }
235 return (fd);
236 } else {
237 /*
238 * Special handling for /dev/fd.
239 * Give up the file pointer
240 * and dup the indicated file descriptor
241 * (in v_rdev). This is ugly, but I've
242 * seen worse.
243 */
244 unfalloc(fp);
245 dupfd = getminor(vp->v_rdev);
246 type = vp->v_type;
247 mutex_enter(&vp->v_lock);
248 vp->v_flag &= ~VDUP;
249 mutex_exit(&vp->v_lock);
250 VN_RELE(vp);
251 if (type != VCHR)
252 return (set_errno(EINVAL));
253 if ((fp = getf(dupfd)) == NULL) {
254 setf(fd, NULL);
255 return (set_errno(EBADF));
256 }
257 mutex_enter(&fp->f_tlock);
258 fp->f_count++;
259 mutex_exit(&fp->f_tlock);
260 setf(fd, fp);
261 if ((filemode & FCLOEXEC) != 0) {
262 f_setfd(fd, FD_CLOEXEC);
263 }
264 releasef(dupfd);
265 }
266 return (fd);
267 } else {
268 setf(fd, NULL);
269 unfalloc(fp);
270 return (set_errno(error));
271 }
272 }
273 } else {
274 error = EINVAL;
275 }
276 out:
277 if (startvp != NULL)
278 VN_RELE(startvp);
279 return (set_errno(error));
280 }
281
282 #define OPENMODE32(fmode) (((fmode) & (FSEARCH | FEXEC))? \
283 (fmode) : (fmode) - FOPEN)
284 #define OPENMODE64(fmode) (OPENMODE32(fmode) | FOFFMAX)
285 #ifdef _LP64
286 #define OPENMODE(fmode) OPENMODE64(fmode)
287 #else
288 #define OPENMODE(fmode) OPENMODE32(fmode)
289 #endif
290
291 /*
292 * Open a file.
293 */
294 int
295 openat(int fd, char *path, int fmode, int cmode)
296 {
297 return (copen(fd, path, OPENMODE(fmode), cmode));
298 }
299
300 int
301 open(char *path, int fmode, int cmode)
302 {
303 return (openat(AT_FDCWD, path, fmode, cmode));
304 }
305
306 #if defined(_ILP32) || defined(_SYSCALL32_IMPL)
307 /*
308 * Open for large files in 32-bit environment. Sets the FOFFMAX flag.
309 */
310 int
311 openat64(int fd, char *path, int fmode, int cmode)
312 {
313 return (copen(fd, path, OPENMODE64(fmode), cmode));
314 }
315
316 int
317 open64(char *path, int fmode, int cmode)
318 {
319 return (openat64(AT_FDCWD, path, fmode, cmode));
320 }
321
322 #endif /* _ILP32 || _SYSCALL32_IMPL */
323
324 #ifdef _SYSCALL32_IMPL
325 /*
326 * Open for 32-bit compatibility on 64-bit kernel
327 */
328 int
329 openat32(int fd, char *path, int fmode, int cmode)
330 {
331 return (copen(fd, path, OPENMODE32(fmode), cmode));
332 }
333
334 int
335 open32(char *path, int fmode, int cmode)
336 {
337 return (openat32(AT_FDCWD, path, fmode, cmode));
338 }
339
340 #endif /* _SYSCALL32_IMPL */