xref: /netbsd/sys/compat/common/vfs_syscalls_43.c (revision d50c96bb)
1 /*	$NetBSD: vfs_syscalls_43.c,v 1.68 2021/09/07 11:43:02 riastradh 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  *	@(#)vfs_syscalls.c	8.28 (Berkeley) 12/10/94
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: vfs_syscalls_43.c,v 1.68 2021/09/07 11:43:02 riastradh Exp $");
41 
42 #if defined(_KERNEL_OPT)
43 #include "opt_compat_netbsd.h"
44 #endif
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/filedesc.h>
49 #include <sys/kernel.h>
50 #include <sys/proc.h>
51 #include <sys/file.h>
52 #include <sys/vnode.h>
53 #include <sys/namei.h>
54 #include <sys/dirent.h>
55 #include <sys/socket.h>
56 #include <sys/socketvar.h>
57 #include <sys/stat.h>
58 #include <sys/malloc.h>
59 #include <sys/ioctl.h>
60 #include <sys/fcntl.h>
61 #include <sys/syslog.h>
62 #include <sys/unistd.h>
63 #include <sys/resourcevar.h>
64 
65 #include <sys/mount.h>
66 #include <sys/syscall.h>
67 #include <sys/syscallvar.h>
68 #include <sys/syscallargs.h>
69 #include <sys/vfs_syscalls.h>
70 
71 #include <compat/sys/stat.h>
72 #include <compat/sys/mount.h>
73 #include <compat/sys/dirent.h>
74 
75 #include <compat/common/compat_util.h>
76 #include <compat/common/compat_mod.h>
77 
78 static struct syscall_package vfs_syscalls_43_syscalls[] = {
79 	{ SYS_compat_43_oquota,     0, (sy_call_t *)compat_43_sys_quota },
80 	{ SYS_compat_43_stat43,     0, (sy_call_t *)compat_43_sys_stat },
81 	{ SYS_compat_43_lstat43,    0, (sy_call_t *)compat_43_sys_lstat },
82 	{ SYS_compat_43_fstat43,    0, (sy_call_t *)compat_43_sys_fstat },
83 	{ SYS_compat_43_otruncate,  0, (sy_call_t *)compat_43_sys_ftruncate },
84 	{ SYS_compat_43_oftruncate, 0, (sy_call_t *)compat_43_sys_ftruncate },
85 	{ SYS_compat_43_olseek,     0, (sy_call_t *)compat_43_sys_lseek },
86 	{ SYS_compat_43_ocreat,     0, (sy_call_t *)compat_43_sys_creat },
87 	{ SYS_compat_43_ogetdirentries, 0,
88 	    (sy_call_t *)compat_43_sys_getdirentries },
89 	{ 0, 0, NULL }
90 };
91 
92 /*
93  * Convert from an old to a new timespec structure.
94  */
95 static void
cvttimespec(struct timespec50 * ots,const struct timespec * ts)96 cvttimespec(struct timespec50 *ots, const struct timespec *ts)
97 {
98 
99 	if (ts->tv_sec > INT_MAX) {
100 #if defined(DEBUG) || 1
101 		static bool first = true;
102 
103 		if (first) {
104 			first = false;
105 			printf("%s[%s:%d]: time_t does not fit\n",
106 			    __func__, curlwp->l_proc->p_comm,
107 			    curlwp->l_lid);
108 		}
109 #endif
110 		ots->tv_sec = INT_MAX;
111 	} else
112 		ots->tv_sec = ts->tv_sec;
113 	ots->tv_nsec = ts->tv_nsec;
114 }
115 
116 /*
117  * Convert from an old to a new stat structure.
118  */
119 static void
cvtstat(struct stat43 * ost,const struct stat * st)120 cvtstat(struct stat43 *ost, const struct stat *st)
121 {
122 
123 	/* Handle any padding. */
124 	memset(ost, 0, sizeof(*ost));
125 	ost->st_dev = st->st_dev;
126 	ost->st_ino = st->st_ino;
127 	ost->st_mode = st->st_mode & 0xffff;
128 	ost->st_nlink = st->st_nlink;
129 	ost->st_uid = st->st_uid;
130 	ost->st_gid = st->st_gid;
131 	ost->st_rdev = st->st_rdev;
132 	if (st->st_size < (quad_t)1 << 32)
133 		ost->st_size = st->st_size;
134 	else
135 		ost->st_size = -2;
136 	cvttimespec(&ost->st_atimespec, &st->st_atimespec);
137 	cvttimespec(&ost->st_mtimespec, &st->st_mtimespec);
138 	cvttimespec(&ost->st_ctimespec, &st->st_ctimespec);
139 	ost->st_blksize = st->st_blksize;
140 	ost->st_blocks = st->st_blocks;
141 	ost->st_flags = st->st_flags;
142 	ost->st_gen = st->st_gen;
143 }
144 
145 /*
146  * Get file status; this version follows links.
147  */
148 /* ARGSUSED */
149 int
compat_43_sys_stat(struct lwp * l,const struct compat_43_sys_stat_args * uap,register_t * retval)150 compat_43_sys_stat(struct lwp *l, const struct compat_43_sys_stat_args *uap, register_t *retval)
151 {
152 	/* {
153 		syscallarg(char *) path;
154 		syscallarg(struct stat43 *) ub;
155 	} */
156 	struct stat sb;
157 	struct stat43 osb;
158 	int error;
159 
160 	error = do_sys_stat(SCARG(uap, path), FOLLOW, &sb);
161 	if (error)
162 		return error;
163 	cvtstat(&osb, &sb);
164 	return copyout(&osb, SCARG(uap, ub), sizeof(osb));
165 }
166 
167 /*
168  * Get file status; this version does not follow links.
169  */
170 /* ARGSUSED */
171 int
compat_43_sys_lstat(struct lwp * l,const struct compat_43_sys_lstat_args * uap,register_t * retval)172 compat_43_sys_lstat(struct lwp *l, const struct compat_43_sys_lstat_args *uap, register_t *retval)
173 {
174 	/* {
175 		syscallarg(char *) path;
176 		syscallarg(struct stat43 *) ub;
177 	} */
178 	struct stat sb;
179 	struct stat43 osb;
180 	int error;
181 
182 	error = do_sys_stat(SCARG(uap, path), NOFOLLOW, &sb);
183 	if (error)
184 		return error;
185 
186 	/*
187 	 * For symbolic links, BSD4.3 returned the attributes of its
188 	 * containing directory, except for mode, size, and links.
189 	 * This is no longer emulated, the parent directory is not consulted.
190 	 */
191 	cvtstat(&osb, &sb);
192 	return copyout(&osb, SCARG(uap, ub), sizeof(osb));
193 }
194 
195 /*
196  * Return status information about a file descriptor.
197  */
198 /* ARGSUSED */
199 int
compat_43_sys_fstat(struct lwp * l,const struct compat_43_sys_fstat_args * uap,register_t * retval)200 compat_43_sys_fstat(struct lwp *l, const struct compat_43_sys_fstat_args *uap, register_t *retval)
201 {
202 	/* {
203 		syscallarg(int) fd;
204 		syscallarg(struct stat43 *) sb;
205 	} */
206 	struct stat sb;
207 	struct stat43 osb;
208 	int error;
209 
210 	error = do_sys_fstat(SCARG(uap, fd), &sb);
211 	if (error)
212 		return error;
213 
214 	cvtstat(&osb, &sb);
215 	return copyout(&osb, SCARG(uap, sb), sizeof(osb));
216 }
217 
218 
219 /*
220  * Truncate a file given a file descriptor.
221  */
222 /* ARGSUSED */
223 int
compat_43_sys_ftruncate(struct lwp * l,const struct compat_43_sys_ftruncate_args * uap,register_t * retval)224 compat_43_sys_ftruncate(struct lwp *l, const struct compat_43_sys_ftruncate_args *uap, register_t *retval)
225 {
226 	/* {
227 		syscallarg(int) fd;
228 		syscallarg(long) length;
229 	} */
230 	struct sys_ftruncate_args /* {
231 		syscallarg(int) fd;
232 		syscallarg(int) pad;
233 		syscallarg(off_t) length;
234 	} */ nuap;
235 
236 	SCARG(&nuap, fd) = SCARG(uap, fd);
237 	SCARG(&nuap, length) = SCARG(uap, length);
238 	return sys_ftruncate(l, &nuap, retval);
239 }
240 
241 /*
242  * Truncate a file given its path name.
243  */
244 /* ARGSUSED */
245 int
compat_43_sys_truncate(struct lwp * l,const struct compat_43_sys_truncate_args * uap,register_t * retval)246 compat_43_sys_truncate(struct lwp *l, const struct compat_43_sys_truncate_args *uap, register_t *retval)
247 {
248 	/* {
249 		syscallarg(char *) path;
250 		syscallarg(long) length;
251 	} */
252 	struct sys_truncate_args /* {
253 		syscallarg(char *) path;
254 		syscallarg(int) pad;
255 		syscallarg(off_t) length;
256 	} */ nuap;
257 
258 	SCARG(&nuap, path) = SCARG(uap, path);
259 	SCARG(&nuap, length) = SCARG(uap, length);
260 	return (sys_truncate(l, &nuap, retval));
261 }
262 
263 
264 /*
265  * Reposition read/write file offset.
266  */
267 int
compat_43_sys_lseek(struct lwp * l,const struct compat_43_sys_lseek_args * uap,register_t * retval)268 compat_43_sys_lseek(struct lwp *l, const struct compat_43_sys_lseek_args *uap, register_t *retval)
269 {
270 	/* {
271 		syscallarg(int) fd;
272 		syscallarg(long) offset;
273 		syscallarg(int) whence;
274 	} */
275 	struct sys_lseek_args /* {
276 		syscallarg(int) fd;
277 		syscallarg(int) pad;
278 		syscallarg(off_t) offset;
279 		syscallarg(int) whence;
280 	} */ nuap;
281 	off_t qret;
282 	int error;
283 
284 	SCARG(&nuap, fd) = SCARG(uap, fd);
285 	SCARG(&nuap, offset) = SCARG(uap, offset);
286 	SCARG(&nuap, whence) = SCARG(uap, whence);
287 	error = sys_lseek(l, &nuap, (register_t *)&qret);
288 	*(long *)retval = qret;
289 	return (error);
290 }
291 
292 
293 /*
294  * Create a file.
295  */
296 int
compat_43_sys_creat(struct lwp * l,const struct compat_43_sys_creat_args * uap,register_t * retval)297 compat_43_sys_creat(struct lwp *l, const struct compat_43_sys_creat_args *uap, register_t *retval)
298 {
299 	/* {
300 		syscallarg(char *) path;
301 		syscallarg(int) mode;
302 	} */
303 	struct sys_open_args /* {
304 		syscallarg(char *) path;
305 		syscallarg(int) flags;
306 		syscallarg(int) mode;
307 	} */ nuap;
308 
309 	SCARG(&nuap, path) = SCARG(uap, path);
310 	SCARG(&nuap, mode) = SCARG(uap, mode);
311 	SCARG(&nuap, flags) = O_WRONLY | O_CREAT | O_TRUNC;
312 	return (sys_open(l, &nuap, retval));
313 }
314 
315 /*ARGSUSED*/
316 int
compat_43_sys_quota(struct lwp * l,const void * v,register_t * retval)317 compat_43_sys_quota(struct lwp *l, const void *v, register_t *retval)
318 {
319 
320 	return (ENOSYS);
321 }
322 
323 
324 /*
325  * Read a block of directory entries in a file system independent format.
326  */
327 int
compat_43_sys_getdirentries(struct lwp * l,const struct compat_43_sys_getdirentries_args * uap,register_t * retval)328 compat_43_sys_getdirentries(struct lwp *l, const struct compat_43_sys_getdirentries_args *uap, register_t *retval)
329 {
330 	/* {
331 		syscallarg(int) fd;
332 		syscallarg(char *) buf;
333 		syscallarg(u_int) count;
334 		syscallarg(long *) basep;
335 	} */
336 	struct dirent *bdp;
337 	struct vnode *vp;
338 	void *tbuf;			/* Current-format */
339 	char *inp;			/* Current-format */
340 	int len, reclen;		/* Current-format */
341 	char *outp;			/* Dirent12-format */
342 	int resid, old_reclen = 0;	/* Dirent12-format */
343 	struct file *fp;
344 	struct uio auio;
345 	struct iovec aiov;
346 	struct dirent43 idb;
347 	off_t off;		/* true file offset */
348 	int buflen, error, eofflag, nbytes;
349 	struct vattr va;
350 	off_t *cookiebuf = NULL, *cookie;
351 	int ncookies;
352 	long loff;
353 
354 	/* fd_getvnode() will use the descriptor for us */
355 	if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0)
356 		return (error);
357 
358 	if ((fp->f_flag & FREAD) == 0) {
359 		error = EBADF;
360 		goto out1;
361 	}
362 
363 	vp = fp->f_vnode;
364 	if (vp->v_type != VDIR) {
365 		error = ENOTDIR;
366 		goto out1;
367 	}
368 
369 	vn_lock(vp, LK_SHARED | LK_RETRY);
370 	error = VOP_GETATTR(vp, &va, l->l_cred);
371 	VOP_UNLOCK(vp);
372 	if (error)
373 		goto out1;
374 
375 	loff = fp->f_offset;
376 	nbytes = SCARG(uap, count);
377 	buflen = uimin(MAXBSIZE, nbytes);
378 	if (buflen < va.va_blocksize)
379 		buflen = va.va_blocksize;
380 	tbuf = malloc(buflen, M_TEMP, M_WAITOK);
381 
382 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
383 	off = fp->f_offset;
384 again:
385 	aiov.iov_base = tbuf;
386 	aiov.iov_len = buflen;
387 	auio.uio_iov = &aiov;
388 	auio.uio_iovcnt = 1;
389 	auio.uio_rw = UIO_READ;
390 	auio.uio_resid = buflen;
391 	auio.uio_offset = off;
392 	UIO_SETUP_SYSSPACE(&auio);
393 	/*
394          * First we read into the malloc'ed buffer, then
395          * we massage it into user space, one record at a time.
396          */
397 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf,
398 	    &ncookies);
399 	if (error)
400 		goto out;
401 
402 	inp = (char *)tbuf;
403 	outp = SCARG(uap, buf);
404 	resid = nbytes;
405 	if ((len = buflen - auio.uio_resid) == 0)
406 		goto eof;
407 
408 	for (cookie = cookiebuf; len > 0; len -= reclen) {
409 		bdp = (struct dirent *)inp;
410 		reclen = bdp->d_reclen;
411 		if (reclen & 3) {
412 			error = EIO;
413 			goto out;
414 		}
415 		if (bdp->d_fileno == 0) {
416 			inp += reclen;	/* it is a hole; squish it out */
417 			if (cookie)
418 				off = *cookie++;
419 			else
420 				off += reclen;
421 			continue;
422 		}
423 		memset(&idb, 0, sizeof(idb));
424 		if (bdp->d_namlen >= sizeof(idb.d_name))
425 			idb.d_namlen = sizeof(idb.d_name) - 1;
426 		else
427 			idb.d_namlen = bdp->d_namlen;
428 		old_reclen = _DIRENT_RECLEN(&idb, bdp->d_namlen);
429 		if (reclen > len || resid < old_reclen) {
430 			/* entry too big for buffer, so just stop */
431 			outp++;
432 			break;
433 		}
434 		/*
435 		 * Massage in place to make a Dirent12-shaped dirent (otherwise
436 		 * we have to worry about touching user memory outside of
437 		 * the copyout() call).
438 		 */
439 		idb.d_fileno = (uint32_t)bdp->d_fileno;
440 		idb.d_reclen = (uint16_t)old_reclen;
441 		idb.d_fileno = (uint32_t)bdp->d_fileno;
442 		(void)memcpy(idb.d_name, bdp->d_name, idb.d_namlen);
443 		memset(idb.d_name + idb.d_namlen, 0,
444 		    idb.d_reclen - _DIRENT_NAMEOFF(&idb) - idb.d_namlen);
445 		if ((error = copyout(&idb, outp, old_reclen)))
446 			goto out;
447 		/* advance past this real entry */
448 		inp += reclen;
449 		if (cookie)
450 			off = *cookie++; /* each entry points to itself */
451 		else
452 			off += reclen;
453 		/* advance output past Dirent12-shaped entry */
454 		outp += old_reclen;
455 		resid -= old_reclen;
456 	}
457 
458 	/* if we squished out the whole block, try again */
459 	if (outp == SCARG(uap, buf)) {
460 		if (cookiebuf)
461 			free(cookiebuf, M_TEMP);
462 		cookiebuf = NULL;
463 		goto again;
464 	}
465 	fp->f_offset = off;	/* update the vnode offset */
466 
467 eof:
468 	*retval = nbytes - resid;
469 out:
470 	VOP_UNLOCK(vp);
471 	if (cookiebuf)
472 		free(cookiebuf, M_TEMP);
473 	free(tbuf, M_TEMP);
474 out1:
475 	fd_putfile(SCARG(uap, fd));
476 	if (error)
477 		return error;
478 	return copyout(&loff, SCARG(uap, basep), sizeof(loff));
479 }
480 
481 int
vfs_syscalls_43_init(void)482 vfs_syscalls_43_init(void)
483 {
484 
485 	return syscall_establish(NULL, vfs_syscalls_43_syscalls);
486 }
487 
488 int
vfs_syscalls_43_fini(void)489 vfs_syscalls_43_fini(void)
490 {
491 
492 	return syscall_disestablish(NULL, vfs_syscalls_43_syscalls);
493 }
494