xref: /netbsd-src/sys/compat/common/vfs_syscalls_12.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: vfs_syscalls_12.c,v 1.30 2014/01/24 22:11:46 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 1.30 2014/01/24 22:11:46 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_data;
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 		strcpy(idb.d_name, bdp->d_name);
200 		if ((error = copyout(&idb, outp, old_reclen)))
201 			goto out;
202 		/* advance past this real entry */
203 		inp += reclen;
204 		if (cookie)
205 			off = *cookie++; /* each entry points to itself */
206 		else
207 			off += reclen;
208 		/* advance output past Dirent12-shaped entry */
209 		outp += old_reclen;
210 		resid -= old_reclen;
211 	}
212 
213 	/* if we squished out the whole block, try again */
214 	if (outp == SCARG(uap, buf)) {
215 		if (cookiebuf)
216 			free(cookiebuf, M_TEMP);
217 		cookiebuf = NULL;
218 		goto again;
219 	}
220 	fp->f_offset = off;	/* update the vnode offset */
221 
222 eof:
223 	*retval = nbytes - resid;
224 out:
225 	VOP_UNLOCK(vp);
226 	if (cookiebuf)
227 		free(cookiebuf, M_TEMP);
228 	free(tbuf, M_TEMP);
229 out1:
230 	fd_putfile(SCARG(uap, fd));
231 	if (error)
232 		return error;
233 	return copyout(&loff, SCARG(uap, basep), sizeof(long));
234 }
235 
236 /*
237  * Get file status; this version follows links.
238  */
239 /* ARGSUSED */
240 int
241 compat_12_sys_stat(struct lwp *l, const struct compat_12_sys_stat_args *uap, register_t *retval)
242 {
243 	/* {
244 		syscallarg(const char *) path;
245 		syscallarg(struct stat12 *) ub;
246 	} */
247 	struct stat sb;
248 	struct stat12 osb;
249 	int error;
250 
251 	error = do_sys_stat(SCARG(uap, path), FOLLOW, &sb);
252 	if (error)
253 		return (error);
254 	compat_12_stat_conv(&sb, &osb);
255 	error = copyout(&osb, SCARG(uap, ub), sizeof (osb));
256 	return (error);
257 }
258 
259 
260 /*
261  * Get file status; this version does not follow links.
262  */
263 /* ARGSUSED */
264 int
265 compat_12_sys_lstat(struct lwp *l, const struct compat_12_sys_lstat_args *uap, register_t *retval)
266 {
267 	/* {
268 		syscallarg(const char *) path;
269 		syscallarg(struct stat12 *) ub;
270 	} */
271 	struct stat sb;
272 	struct stat12 osb;
273 	int error;
274 
275 	error = do_sys_stat(SCARG(uap, path), NOFOLLOW, &sb);
276 	if (error)
277 		return (error);
278 	compat_12_stat_conv(&sb, &osb);
279 	error = copyout(&osb, SCARG(uap, ub), sizeof (osb));
280 	return (error);
281 }
282 
283 /*
284  * Return status information about a file descriptor.
285  */
286 /* ARGSUSED */
287 int
288 compat_12_sys_fstat(struct lwp *l, const struct compat_12_sys_fstat_args *uap, register_t *retval)
289 {
290 	/* {
291 		syscallarg(int) fd;
292 		syscallarg(struct stat12 *) sb;
293 	} */
294 	struct stat ub;
295 	struct stat12 oub;
296 	int error;
297 
298 	error = do_sys_fstat(SCARG(uap, fd), &ub);
299 	if (error == 0) {
300 		compat_12_stat_conv(&ub, &oub);
301 		error = copyout(&oub, SCARG(uap, sb), sizeof (oub));
302 	}
303 	return (error);
304 }
305