xref: /netbsd-src/sys/compat/common/vfs_syscalls_43.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: vfs_syscalls_43.c,v 1.62 2017/12/03 15:23:30 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  *	@(#)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 1.62 2017/12/03 15:23:30 christos 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/sysctl.h>
62 #include <sys/syslog.h>
63 #include <sys/unistd.h>
64 #include <sys/resourcevar.h>
65 #include <sys/sysctl.h>
66 
67 #include <sys/mount.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 void cvttimespec(struct timespec *, struct timespec50 *);
79 static void cvtstat(struct stat *, struct stat43 *);
80 
81 /*
82  * Convert from an old to a new timespec structure.
83  */
84 static void
85 cvttimespec(struct timespec *ts, struct timespec50 *ots)
86 {
87 
88 	if (ts->tv_sec > INT_MAX) {
89 #if defined(DEBUG) || 1
90 		static bool first = true;
91 
92 		if (first) {
93 			first = false;
94 			printf("%s[%s:%d]: time_t does not fit\n",
95 			    __func__, curlwp->l_proc->p_comm,
96 			    curlwp->l_lid);
97 		}
98 #endif
99 		ots->tv_sec = INT_MAX;
100 	} else
101 		ots->tv_sec = ts->tv_sec;
102 	ots->tv_nsec = ts->tv_nsec;
103 }
104 
105 /*
106  * Convert from an old to a new stat structure.
107  */
108 static void
109 cvtstat(struct stat *st, struct stat43 *ost)
110 {
111 
112 	/* Handle any padding. */
113 	memset(ost, 0, sizeof *ost);
114 	ost->st_dev = st->st_dev;
115 	ost->st_ino = st->st_ino;
116 	ost->st_mode = st->st_mode & 0xffff;
117 	ost->st_nlink = st->st_nlink;
118 	ost->st_uid = st->st_uid;
119 	ost->st_gid = st->st_gid;
120 	ost->st_rdev = st->st_rdev;
121 	if (st->st_size < (quad_t)1 << 32)
122 		ost->st_size = st->st_size;
123 	else
124 		ost->st_size = -2;
125 	cvttimespec(&st->st_atimespec, &ost->st_atimespec);
126 	cvttimespec(&st->st_mtimespec, &ost->st_mtimespec);
127 	cvttimespec(&st->st_ctimespec, &ost->st_ctimespec);
128 	ost->st_blksize = st->st_blksize;
129 	ost->st_blocks = st->st_blocks;
130 	ost->st_flags = st->st_flags;
131 	ost->st_gen = st->st_gen;
132 }
133 
134 /*
135  * Get file status; this version follows links.
136  */
137 /* ARGSUSED */
138 int
139 compat_43_sys_stat(struct lwp *l, const struct compat_43_sys_stat_args *uap, register_t *retval)
140 {
141 	/* {
142 		syscallarg(char *) path;
143 		syscallarg(struct stat43 *) ub;
144 	} */
145 	struct stat sb;
146 	struct stat43 osb;
147 	int error;
148 
149 	error = do_sys_stat(SCARG(uap, path), FOLLOW, &sb);
150 	if (error)
151 		return (error);
152 	cvtstat(&sb, &osb);
153 	error = copyout((void *)&osb, (void *)SCARG(uap, ub), sizeof (osb));
154 	return (error);
155 }
156 
157 /*
158  * Get file status; this version does not follow links.
159  */
160 /* ARGSUSED */
161 int
162 compat_43_sys_lstat(struct lwp *l, const struct compat_43_sys_lstat_args *uap, register_t *retval)
163 {
164 	/* {
165 		syscallarg(char *) path;
166 		syscallarg(struct ostat *) ub;
167 	} */
168 	struct vnode *vp, *dvp;
169 	struct stat sb, sb1;
170 	struct stat43 osb;
171 	int error;
172 	struct pathbuf *pb;
173 	struct nameidata nd;
174 	int ndflags;
175 
176 	error = pathbuf_copyin(SCARG(uap, path), &pb);
177 	if (error) {
178 		return error;
179 	}
180 
181 	ndflags = NOFOLLOW | LOCKLEAF | LOCKPARENT | TRYEMULROOT;
182 again:
183 	NDINIT(&nd, LOOKUP, ndflags, pb);
184 	if ((error = namei(&nd))) {
185 		if (error == EISDIR && (ndflags & LOCKPARENT) != 0) {
186 			/*
187 			 * Should only happen on '/'. Retry without LOCKPARENT;
188 			 * this is safe since the vnode won't be a VLNK.
189 			 */
190 			ndflags &= ~LOCKPARENT;
191 			goto again;
192 		}
193 		pathbuf_destroy(pb);
194 		return (error);
195 	}
196 	/*
197 	 * For symbolic links, always return the attributes of its
198 	 * containing directory, except for mode, size, and links.
199 	 */
200 	vp = nd.ni_vp;
201 	dvp = nd.ni_dvp;
202 	pathbuf_destroy(pb);
203 	if (vp->v_type != VLNK) {
204 		if ((ndflags & LOCKPARENT) != 0) {
205 			if (dvp == vp)
206 				vrele(dvp);
207 			else
208 				vput(dvp);
209 		}
210 		error = vn_stat(vp, &sb);
211 		vput(vp);
212 		if (error)
213 			return (error);
214 	} else {
215 		error = vn_stat(dvp, &sb);
216 		vput(dvp);
217 		if (error) {
218 			vput(vp);
219 			return (error);
220 		}
221 		error = vn_stat(vp, &sb1);
222 		vput(vp);
223 		if (error)
224 			return (error);
225 		sb.st_mode &= ~S_IFDIR;
226 		sb.st_mode |= S_IFLNK;
227 		sb.st_nlink = sb1.st_nlink;
228 		sb.st_size = sb1.st_size;
229 		sb.st_blocks = sb1.st_blocks;
230 	}
231 	cvtstat(&sb, &osb);
232 	error = copyout((void *)&osb, (void *)SCARG(uap, ub), sizeof (osb));
233 	return (error);
234 }
235 
236 /*
237  * Return status information about a file descriptor.
238  */
239 /* ARGSUSED */
240 int
241 compat_43_sys_fstat(struct lwp *l, const struct compat_43_sys_fstat_args *uap, register_t *retval)
242 {
243 	/* {
244 		syscallarg(int) fd;
245 		syscallarg(struct stat43 *) sb;
246 	} */
247 	struct stat ub;
248 	struct stat43 oub;
249 	int error;
250 
251 	error = do_sys_fstat(SCARG(uap, fd), &ub);
252 	if (error == 0) {
253 		cvtstat(&ub, &oub);
254 		error = copyout((void *)&oub, (void *)SCARG(uap, sb),
255 		    sizeof (oub));
256 	}
257 
258 	return (error);
259 }
260 
261 
262 /*
263  * Truncate a file given a file descriptor.
264  */
265 /* ARGSUSED */
266 int
267 compat_43_sys_ftruncate(struct lwp *l, const struct compat_43_sys_ftruncate_args *uap, register_t *retval)
268 {
269 	/* {
270 		syscallarg(int) fd;
271 		syscallarg(long) length;
272 	} */
273 	struct sys_ftruncate_args /* {
274 		syscallarg(int) fd;
275 		syscallarg(int) pad;
276 		syscallarg(off_t) length;
277 	} */ nuap;
278 
279 	SCARG(&nuap, fd) = SCARG(uap, fd);
280 	SCARG(&nuap, length) = SCARG(uap, length);
281 	return (sys_ftruncate(l, &nuap, retval));
282 }
283 
284 /*
285  * Truncate a file given its path name.
286  */
287 /* ARGSUSED */
288 int
289 compat_43_sys_truncate(struct lwp *l, const struct compat_43_sys_truncate_args *uap, register_t *retval)
290 {
291 	/* {
292 		syscallarg(char *) path;
293 		syscallarg(long) length;
294 	} */
295 	struct sys_truncate_args /* {
296 		syscallarg(char *) path;
297 		syscallarg(int) pad;
298 		syscallarg(off_t) length;
299 	} */ nuap;
300 
301 	SCARG(&nuap, path) = SCARG(uap, path);
302 	SCARG(&nuap, length) = SCARG(uap, length);
303 	return (sys_truncate(l, &nuap, retval));
304 }
305 
306 
307 /*
308  * Reposition read/write file offset.
309  */
310 int
311 compat_43_sys_lseek(struct lwp *l, const struct compat_43_sys_lseek_args *uap, register_t *retval)
312 {
313 	/* {
314 		syscallarg(int) fd;
315 		syscallarg(long) offset;
316 		syscallarg(int) whence;
317 	} */
318 	struct sys_lseek_args /* {
319 		syscallarg(int) fd;
320 		syscallarg(int) pad;
321 		syscallarg(off_t) offset;
322 		syscallarg(int) whence;
323 	} */ nuap;
324 	off_t qret;
325 	int error;
326 
327 	SCARG(&nuap, fd) = SCARG(uap, fd);
328 	SCARG(&nuap, offset) = SCARG(uap, offset);
329 	SCARG(&nuap, whence) = SCARG(uap, whence);
330 	error = sys_lseek(l, &nuap, (register_t *)&qret);
331 	*(long *)retval = qret;
332 	return (error);
333 }
334 
335 
336 /*
337  * Create a file.
338  */
339 int
340 compat_43_sys_creat(struct lwp *l, const struct compat_43_sys_creat_args *uap, register_t *retval)
341 {
342 	/* {
343 		syscallarg(char *) path;
344 		syscallarg(int) mode;
345 	} */
346 	struct sys_open_args /* {
347 		syscallarg(char *) path;
348 		syscallarg(int) flags;
349 		syscallarg(int) mode;
350 	} */ nuap;
351 
352 	SCARG(&nuap, path) = SCARG(uap, path);
353 	SCARG(&nuap, mode) = SCARG(uap, mode);
354 	SCARG(&nuap, flags) = O_WRONLY | O_CREAT | O_TRUNC;
355 	return (sys_open(l, &nuap, retval));
356 }
357 
358 /*ARGSUSED*/
359 int
360 compat_43_sys_quota(struct lwp *l, const void *v, register_t *retval)
361 {
362 
363 	return (ENOSYS);
364 }
365 
366 
367 /*
368  * Read a block of directory entries in a file system independent format.
369  */
370 int
371 compat_43_sys_getdirentries(struct lwp *l, const struct compat_43_sys_getdirentries_args *uap, register_t *retval)
372 {
373 	/* {
374 		syscallarg(int) fd;
375 		syscallarg(char *) buf;
376 		syscallarg(u_int) count;
377 		syscallarg(long *) basep;
378 	} */
379 	struct dirent *bdp;
380 	struct vnode *vp;
381 	void *tbuf;			/* Current-format */
382 	char *inp;			/* Current-format */
383 	int len, reclen;		/* Current-format */
384 	char *outp;			/* Dirent12-format */
385 	int resid, old_reclen = 0;	/* Dirent12-format */
386 	struct file *fp;
387 	struct uio auio;
388 	struct iovec aiov;
389 	struct dirent43 idb;
390 	off_t off;		/* true file offset */
391 	int buflen, error, eofflag, nbytes;
392 	struct vattr va;
393 	off_t *cookiebuf = NULL, *cookie;
394 	int ncookies;
395 	long loff;
396 
397 	/* fd_getvnode() will use the descriptor for us */
398 	if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0)
399 		return (error);
400 
401 	if ((fp->f_flag & FREAD) == 0) {
402 		error = EBADF;
403 		goto out1;
404 	}
405 
406 	vp = fp->f_vnode;
407 	if (vp->v_type != VDIR) {
408 		error = ENOTDIR;
409 		goto out1;
410 	}
411 
412 	vn_lock(vp, LK_SHARED | LK_RETRY);
413 	error = VOP_GETATTR(vp, &va, l->l_cred);
414 	VOP_UNLOCK(vp);
415 	if (error)
416 		goto out1;
417 
418 	loff = fp->f_offset;
419 	nbytes = SCARG(uap, count);
420 	buflen = min(MAXBSIZE, nbytes);
421 	if (buflen < va.va_blocksize)
422 		buflen = va.va_blocksize;
423 	tbuf = malloc(buflen, M_TEMP, M_WAITOK);
424 
425 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
426 	off = fp->f_offset;
427 again:
428 	aiov.iov_base = tbuf;
429 	aiov.iov_len = buflen;
430 	auio.uio_iov = &aiov;
431 	auio.uio_iovcnt = 1;
432 	auio.uio_rw = UIO_READ;
433 	auio.uio_resid = buflen;
434 	auio.uio_offset = off;
435 	UIO_SETUP_SYSSPACE(&auio);
436 	/*
437          * First we read into the malloc'ed buffer, then
438          * we massage it into user space, one record at a time.
439          */
440 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf,
441 	    &ncookies);
442 	if (error)
443 		goto out;
444 
445 	inp = (char *)tbuf;
446 	outp = SCARG(uap, buf);
447 	resid = nbytes;
448 	if ((len = buflen - auio.uio_resid) == 0)
449 		goto eof;
450 
451 	for (cookie = cookiebuf; len > 0; len -= reclen) {
452 		bdp = (struct dirent *)inp;
453 		reclen = bdp->d_reclen;
454 		if (reclen & 3) {
455 			error = EIO;
456 			goto out;
457 		}
458 		if (bdp->d_fileno == 0) {
459 			inp += reclen;	/* it is a hole; squish it out */
460 			if (cookie)
461 				off = *cookie++;
462 			else
463 				off += reclen;
464 			continue;
465 		}
466 		if (bdp->d_namlen >= sizeof(idb.d_name))
467 			idb.d_namlen = sizeof(idb.d_name) - 1;
468 		else
469 			idb.d_namlen = bdp->d_namlen;
470 		old_reclen = _DIRENT_RECLEN(&idb, bdp->d_namlen);
471 		if (reclen > len || resid < old_reclen) {
472 			/* entry too big for buffer, so just stop */
473 			outp++;
474 			break;
475 		}
476 		/*
477 		 * Massage in place to make a Dirent12-shaped dirent (otherwise
478 		 * we have to worry about touching user memory outside of
479 		 * the copyout() call).
480 		 */
481 		idb.d_fileno = (uint32_t)bdp->d_fileno;
482 		idb.d_reclen = (uint16_t)old_reclen;
483 		idb.d_fileno = (uint32_t)bdp->d_fileno;
484 		(void)memcpy(idb.d_name, bdp->d_name, idb.d_namlen);
485 		memset(idb.d_name + idb.d_namlen, 0,
486 		    idb.d_reclen - _DIRENT_NAMEOFF(&idb) - idb.d_namlen);
487 		if ((error = copyout(&idb, outp, old_reclen)))
488 			goto out;
489 		/* advance past this real entry */
490 		inp += reclen;
491 		if (cookie)
492 			off = *cookie++; /* each entry points to itself */
493 		else
494 			off += reclen;
495 		/* advance output past Dirent12-shaped entry */
496 		outp += old_reclen;
497 		resid -= old_reclen;
498 	}
499 
500 	/* if we squished out the whole block, try again */
501 	if (outp == SCARG(uap, buf)) {
502 		if (cookiebuf)
503 			free(cookiebuf, M_TEMP);
504 		cookiebuf = NULL;
505 		goto again;
506 	}
507 	fp->f_offset = off;	/* update the vnode offset */
508 
509 eof:
510 	*retval = nbytes - resid;
511 out:
512 	VOP_UNLOCK(vp);
513 	if (cookiebuf)
514 		free(cookiebuf, M_TEMP);
515 	free(tbuf, M_TEMP);
516 out1:
517 	fd_putfile(SCARG(uap, fd));
518 	if (error)
519 		return error;
520 	return copyout(&loff, SCARG(uap, basep), sizeof(long));
521 }
522 
523 /*
524  * sysctl helper routine for vfs.generic.conf lookups.
525  */
526 #if defined(COMPAT_09) || defined(COMPAT_43) || defined(COMPAT_44)
527 
528 static int
529 sysctl_vfs_generic_conf(SYSCTLFN_ARGS)
530 {
531         struct vfsconf vfc;
532 	struct sysctlnode node;
533 	struct vfsops *vfsp;
534 	u_int vfsnum;
535 
536 	if (namelen != 1)
537 		return (ENOTDIR);
538 	vfsnum = name[0];
539 	if (vfsnum >= nmountcompatnames ||
540 	    mountcompatnames[vfsnum] == NULL)
541 		return (EOPNOTSUPP);
542 	vfsp = vfs_getopsbyname(mountcompatnames[vfsnum]);
543 	if (vfsp == NULL)
544 		return (EOPNOTSUPP);
545 
546 	vfc.vfc_vfsops = vfsp;
547 	strncpy(vfc.vfc_name, vfsp->vfs_name, sizeof(vfc.vfc_name));
548 	vfc.vfc_typenum = vfsnum;
549 	vfc.vfc_refcount = vfsp->vfs_refcount;
550 	vfc.vfc_flags = 0;
551 	vfc.vfc_mountroot = vfsp->vfs_mountroot;
552 	vfc.vfc_next = NULL;
553 	vfs_delref(vfsp);
554 
555 	node = *rnode;
556 	node.sysctl_data = &vfc;
557 	return (sysctl_lookup(SYSCTLFN_CALL(&node)));
558 }
559 
560 /*
561  * Top level filesystem related information gathering.
562  */
563 void
564 compat_sysctl_vfs(struct sysctllog **clog)
565 {
566 
567 	sysctl_createv(clog, 0, NULL, NULL,
568 		       CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
569 		       CTLTYPE_INT, "maxtypenum",
570 		       SYSCTL_DESCR("Highest valid filesystem type number"),
571 		       NULL, nmountcompatnames, NULL, 0,
572 		       CTL_VFS, VFS_GENERIC, VFS_MAXTYPENUM, CTL_EOL);
573 	sysctl_createv(clog, 0, NULL, NULL,
574 		       CTLFLAG_PERMANENT,
575 		       CTLTYPE_STRUCT, "conf",
576 		       SYSCTL_DESCR("Filesystem configuration information"),
577 		       sysctl_vfs_generic_conf, 0, NULL,
578 		       sizeof(struct vfsconf),
579 		       CTL_VFS, VFS_GENERIC, VFS_CONF, CTL_EOL);
580 }
581 #endif
582