vfs_syscalls_12.c revision 1.32 1 /* $NetBSD: vfs_syscalls_12.c,v 1.32 2017/01/13 20:58:59 christos Exp $ */
2
3 /*
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * From: @(#)vfs_syscalls.c 8.28 (Berkeley) 12/10/94
37 */
38
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: vfs_syscalls_12.c,v 1.32 2017/01/13 20:58:59 christos Exp $");
41
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/namei.h>
45 #include <sys/filedesc.h>
46 #include <sys/kernel.h>
47 #include <sys/file.h>
48 #include <sys/stat.h>
49 #include <sys/socketvar.h>
50 #include <sys/vnode.h>
51 #include <sys/proc.h>
52 #include <sys/uio.h>
53 #include <sys/dirent.h>
54 #include <sys/vfs_syscalls.h>
55
56 #include <sys/syscallargs.h>
57
58 #include <compat/sys/stat.h>
59 #include <compat/sys/dirent.h>
60
61 /*
62 * Convert from a new to an old stat structure.
63 */
64 void
65 compat_12_stat_conv(const struct stat *st, struct stat12 *ost)
66 {
67
68 ost->st_dev = st->st_dev;
69 ost->st_ino = st->st_ino;
70 ost->st_mode = st->st_mode & 0xffff;
71 if (st->st_nlink >= (1 << 15))
72 ost->st_nlink = (1 << 15) - 1;
73 else
74 ost->st_nlink = st->st_nlink;
75 ost->st_uid = st->st_uid;
76 ost->st_gid = st->st_gid;
77 ost->st_rdev = st->st_rdev;
78 timespec_to_timespec50(&st->st_atimespec, &ost->st_atimespec);
79 timespec_to_timespec50(&st->st_mtimespec, &ost->st_mtimespec);
80 timespec_to_timespec50(&st->st_ctimespec, &ost->st_ctimespec);
81 ost->st_size = st->st_size;
82 ost->st_blocks = st->st_blocks;
83 ost->st_blksize = st->st_blksize;
84 ost->st_flags = st->st_flags;
85 ost->st_gen = st->st_gen;
86 }
87
88 /*
89 * Read a block of directory entries in a file system independent format.
90 */
91 int
92 compat_12_sys_getdirentries(struct lwp *l, const struct compat_12_sys_getdirentries_args *uap, register_t *retval)
93 {
94 /* {
95 syscallarg(int) fd;
96 syscallarg(char *) buf;
97 syscallarg(u_int) count;
98 syscallarg(long *) basep;
99 } */
100 struct dirent *bdp;
101 struct vnode *vp;
102 char *inp, *tbuf; /* Current-format */
103 int len, reclen; /* Current-format */
104 char *outp; /* Dirent12-format */
105 int resid, old_reclen = 0; /* Dirent12-format */
106 struct file *fp;
107 struct uio auio;
108 struct iovec aiov;
109 struct dirent12 idb;
110 off_t off; /* true file offset */
111 int buflen, error, eofflag, nbytes;
112 struct vattr va;
113 off_t *cookiebuf = NULL, *cookie;
114 int ncookies;
115 long loff;
116
117 /* fd_getvnode() will use the descriptor for us */
118 if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0)
119 return (error);
120
121 if ((fp->f_flag & FREAD) == 0) {
122 error = EBADF;
123 goto out1;
124 }
125
126 vp = (struct vnode *)fp->f_vnode;
127 if (vp->v_type != VDIR) {
128 error = ENOTDIR;
129 goto out1;
130 }
131
132 vn_lock(vp, LK_SHARED | LK_RETRY);
133 error = VOP_GETATTR(vp, &va, l->l_cred);
134 VOP_UNLOCK(vp);
135 if (error)
136 goto out1;
137
138 loff = fp->f_offset;
139 nbytes = SCARG(uap, count);
140 buflen = min(MAXBSIZE, nbytes);
141 if (buflen < va.va_blocksize)
142 buflen = va.va_blocksize;
143 tbuf = malloc(buflen, M_TEMP, M_WAITOK);
144
145 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
146 off = fp->f_offset;
147 again:
148 aiov.iov_base = tbuf;
149 aiov.iov_len = buflen;
150 auio.uio_iov = &aiov;
151 auio.uio_iovcnt = 1;
152 auio.uio_rw = UIO_READ;
153 auio.uio_resid = buflen;
154 auio.uio_offset = off;
155 UIO_SETUP_SYSSPACE(&auio);
156 /*
157 * First we read into the malloc'ed buffer, then
158 * we massage it into user space, one record at a time.
159 */
160 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf,
161 &ncookies);
162 if (error)
163 goto out;
164
165 inp = tbuf;
166 outp = SCARG(uap, buf);
167 resid = nbytes;
168 if ((len = buflen - auio.uio_resid) == 0)
169 goto eof;
170
171 for (cookie = cookiebuf; len > 0; len -= reclen) {
172 bdp = (struct dirent *)inp;
173 reclen = bdp->d_reclen;
174 if (reclen & 3)
175 panic(__func__);
176 if (bdp->d_fileno == 0) {
177 inp += reclen; /* it is a hole; squish it out */
178 if (cookie)
179 off = *cookie++;
180 else
181 off += reclen;
182 continue;
183 }
184 old_reclen = _DIRENT_RECLEN(&idb, bdp->d_namlen);
185 if (reclen > len || resid < old_reclen) {
186 /* entry too big for buffer, so just stop */
187 outp++;
188 break;
189 }
190 /*
191 * Massage in place to make a Dirent12-shaped dirent (otherwise
192 * we have to worry about touching user memory outside of
193 * the copyout() call).
194 */
195 idb.d_fileno = (uint32_t)bdp->d_fileno;
196 idb.d_reclen = (uint16_t)old_reclen;
197 idb.d_type = (uint8_t)bdp->d_type;
198 idb.d_namlen = (uint8_t)bdp->d_namlen;
199 memcpy(idb.d_name, bdp->d_name, MIN(sizeof(idb.d_name),
200 idb.d_namlen));
201 if ((error = copyout(&idb, outp, old_reclen)))
202 goto out;
203 /* advance past this real entry */
204 inp += reclen;
205 if (cookie)
206 off = *cookie++; /* each entry points to itself */
207 else
208 off += reclen;
209 /* advance output past Dirent12-shaped entry */
210 outp += old_reclen;
211 resid -= old_reclen;
212 }
213
214 /* if we squished out the whole block, try again */
215 if (outp == SCARG(uap, buf)) {
216 if (cookiebuf)
217 free(cookiebuf, M_TEMP);
218 cookiebuf = NULL;
219 goto again;
220 }
221 fp->f_offset = off; /* update the vnode offset */
222
223 eof:
224 *retval = nbytes - resid;
225 out:
226 VOP_UNLOCK(vp);
227 if (cookiebuf)
228 free(cookiebuf, M_TEMP);
229 free(tbuf, M_TEMP);
230 out1:
231 fd_putfile(SCARG(uap, fd));
232 if (error)
233 return error;
234 return copyout(&loff, SCARG(uap, basep), sizeof(long));
235 }
236
237 /*
238 * Get file status; this version follows links.
239 */
240 /* ARGSUSED */
241 int
242 compat_12_sys_stat(struct lwp *l, const struct compat_12_sys_stat_args *uap, register_t *retval)
243 {
244 /* {
245 syscallarg(const char *) path;
246 syscallarg(struct stat12 *) ub;
247 } */
248 struct stat sb;
249 struct stat12 osb;
250 int error;
251
252 error = do_sys_stat(SCARG(uap, path), FOLLOW, &sb);
253 if (error)
254 return (error);
255 compat_12_stat_conv(&sb, &osb);
256 error = copyout(&osb, SCARG(uap, ub), sizeof (osb));
257 return (error);
258 }
259
260
261 /*
262 * Get file status; this version does not follow links.
263 */
264 /* ARGSUSED */
265 int
266 compat_12_sys_lstat(struct lwp *l, const struct compat_12_sys_lstat_args *uap, register_t *retval)
267 {
268 /* {
269 syscallarg(const char *) path;
270 syscallarg(struct stat12 *) ub;
271 } */
272 struct stat sb;
273 struct stat12 osb;
274 int error;
275
276 error = do_sys_stat(SCARG(uap, path), NOFOLLOW, &sb);
277 if (error)
278 return (error);
279 compat_12_stat_conv(&sb, &osb);
280 error = copyout(&osb, SCARG(uap, ub), sizeof (osb));
281 return (error);
282 }
283
284 /*
285 * Return status information about a file descriptor.
286 */
287 /* ARGSUSED */
288 int
289 compat_12_sys_fstat(struct lwp *l, const struct compat_12_sys_fstat_args *uap, register_t *retval)
290 {
291 /* {
292 syscallarg(int) fd;
293 syscallarg(struct stat12 *) sb;
294 } */
295 struct stat ub;
296 struct stat12 oub;
297 int error;
298
299 error = do_sys_fstat(SCARG(uap, fd), &ub);
300 if (error == 0) {
301 compat_12_stat_conv(&ub, &oub);
302 error = copyout(&oub, SCARG(uap, sb), sizeof (oub));
303 }
304 return (error);
305 }
306