xref: /netbsd-src/sys/compat/common/vfs_syscalls_20.c (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /*	$NetBSD: vfs_syscalls_20.c,v 1.41 2019/01/27 02:08:39 pgoyette 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	8.42 (Berkeley) 7/31/95
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: vfs_syscalls_20.c,v 1.41 2019/01/27 02:08:39 pgoyette Exp $");
41 
42 #ifdef _KERNEL_OPT
43 #include "opt_compat_netbsd.h"
44 #endif
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/namei.h>
49 #include <sys/filedesc.h>
50 #include <sys/kernel.h>
51 #include <sys/file.h>
52 #include <sys/stat.h>
53 #include <sys/vnode.h>
54 #include <sys/mount.h>
55 #include <sys/proc.h>
56 #include <sys/uio.h>
57 #include <sys/malloc.h>
58 #include <sys/dirent.h>
59 #include <sys/sysctl.h>
60 #include <sys/syscall.h>
61 #include <sys/syscallvar.h>
62 #include <sys/syscallargs.h>
63 #include <sys/kauth.h>
64 
65 #include <compat/common/compat_mod.h>
66 
67 #include <compat/sys/mount.h>
68 
69 #define MOUNTNO_NONE	0
70 #define MOUNTNO_UFS	1		/* UNIX "Fast" Filesystem */
71 #define MOUNTNO_NFS	2		/* Network Filesystem */
72 #define MOUNTNO_MFS	3		/* Memory Filesystem */
73 #define MOUNTNO_MSDOS	4		/* MSDOS Filesystem */
74 #define MOUNTNO_CD9660	5		/* iso9660 cdrom */
75 #define MOUNTNO_FDESC	6		/* /dev/fd filesystem */
76 #define MOUNTNO_KERNFS	7		/* kernel variable filesystem */
77 #define MOUNTNO_DEVFS	8		/* device node filesystem */
78 #define MOUNTNO_AFS	9		/* AFS 3.x */
79 static const struct {
80 	const char *name;
81 	const int value;
82 } nv[] = {
83 	{ MOUNT_UFS, MOUNTNO_UFS },
84 	{ MOUNT_NFS, MOUNTNO_NFS },
85 	{ MOUNT_MFS, MOUNTNO_MFS },
86 	{ MOUNT_MSDOS, MOUNTNO_MSDOS },
87 	{ MOUNT_CD9660, MOUNTNO_CD9660 },
88 	{ MOUNT_FDESC, MOUNTNO_FDESC },
89 	{ MOUNT_KERNFS, MOUNTNO_KERNFS },
90 	{ MOUNT_AFS, MOUNTNO_AFS },
91 };
92 
93 static const struct syscall_package vfs_syscalls_20_syscalls[] = {
94 	{ SYS_compat_20_fhstatfs, 0, (sy_call_t *)compat_20_sys_fhstatfs },
95 	{ SYS_compat_20_fstatfs, 0, (sy_call_t *)compat_20_sys_fstatfs },
96 	{ SYS_compat_20_getfsstat, 0, (sy_call_t *)compat_20_sys_getfsstat },
97 	{ SYS_compat_20_statfs, 0, (sy_call_t *)compat_20_sys_statfs },
98 	{ 0, 0, NULL }
99 };
100 
101 static int
102 vfs2fs(struct statfs12 *bfs, const struct statvfs *fs)
103 {
104 	struct statfs12 ofs;
105 	int i;
106 	ofs.f_type = 0;
107 	ofs.f_oflags = (short)fs->f_flag;
108 
109 	for (i = 0; i < sizeof(nv) / sizeof(nv[0]); i++) {
110 		if (strcmp(nv[i].name, fs->f_fstypename) == 0) {
111 			ofs.f_type = nv[i].value;
112 			break;
113 		}
114 	}
115 #define CLAMP(a)	(long)(((a) & ~LONG_MAX) ? LONG_MAX : (a))
116 	ofs.f_bsize = CLAMP(fs->f_frsize);
117 	ofs.f_iosize = CLAMP(fs->f_iosize);
118 	ofs.f_blocks = CLAMP(fs->f_blocks);
119 	ofs.f_bfree = CLAMP(fs->f_bfree);
120 	if (fs->f_bfree > fs->f_bresvd)
121 		ofs.f_bavail = CLAMP(fs->f_bfree - fs->f_bresvd);
122 	else
123 		ofs.f_bavail = -CLAMP(fs->f_bresvd - fs->f_bfree);
124 	ofs.f_files = CLAMP(fs->f_files);
125 	ofs.f_ffree = CLAMP(fs->f_ffree);
126 	ofs.f_fsid = fs->f_fsidx;
127 	ofs.f_owner = fs->f_owner;
128 	ofs.f_flags = (long)fs->f_flag;
129 	ofs.f_syncwrites = CLAMP(fs->f_syncwrites);
130 	ofs.f_asyncwrites = CLAMP(fs->f_asyncwrites);
131 	(void)strncpy(ofs.f_fstypename, fs->f_fstypename,
132 	    sizeof(ofs.f_fstypename));
133 	(void)strncpy(ofs.f_mntonname, fs->f_mntonname,
134 	    sizeof(ofs.f_mntonname));
135 	(void)strncpy(ofs.f_mntfromname, fs->f_mntfromname,
136 	    sizeof(ofs.f_mntfromname));
137 
138 	return copyout(&ofs, bfs, sizeof(ofs));
139 }
140 
141 /*
142  * Get filesystem statistics.
143  */
144 /* ARGSUSED */
145 int
146 compat_20_sys_statfs(struct lwp *l, const struct compat_20_sys_statfs_args *uap, register_t *retval)
147 {
148 	/* {
149 		syscallarg(const char *) path;
150 		syscallarg(struct statfs12 *) buf;
151 	} */
152 	struct mount *mp;
153 	struct statvfs *sbuf;
154 	int error;
155 	struct vnode *vp;
156 
157 	error = namei_simple_user(SCARG(uap, path),
158 			NSM_FOLLOW_TRYEMULROOT, &vp);
159 	if (error != 0)
160 		return error;
161 
162 	mp = vp->v_mount;
163 
164 	sbuf = malloc(sizeof(*sbuf), M_TEMP, M_WAITOK);
165 	if ((error = dostatvfs(mp, sbuf, l, 0, 1)) != 0)
166 		goto done;
167 
168 	error = vfs2fs(SCARG(uap, buf), sbuf);
169 done:
170 	vrele(vp);
171 	free(sbuf, M_TEMP);
172 	return error;
173 }
174 
175 /*
176  * Get filesystem statistics.
177  */
178 /* ARGSUSED */
179 int
180 compat_20_sys_fstatfs(struct lwp *l, const struct compat_20_sys_fstatfs_args *uap, register_t *retval)
181 {
182 	/* {
183 		syscallarg(int) fd;
184 		syscallarg(struct statfs12 *) buf;
185 	} */
186 	struct file *fp;
187 	struct mount *mp;
188 	struct statvfs *sbuf;
189 	int error;
190 
191 	/* fd_getvnode() will use the descriptor for us */
192 	if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0)
193 		return (error);
194 	mp = fp->f_vnode->v_mount;
195 	sbuf = malloc(sizeof(*sbuf), M_TEMP, M_WAITOK);
196 	if ((error = dostatvfs(mp, sbuf, l, 0, 1)) != 0)
197 		goto out;
198 	error = vfs2fs(SCARG(uap, buf), sbuf);
199  out:
200 	fd_putfile(SCARG(uap, fd));
201 	free(sbuf, M_TEMP);
202 	return error;
203 }
204 
205 
206 /*
207  * Get statistics on all filesystems.
208  */
209 int
210 compat_20_sys_getfsstat(struct lwp *l, const struct compat_20_sys_getfsstat_args *uap, register_t *retval)
211 {
212 	/* {
213 		syscallarg(struct statfs12 *) buf;
214 		syscallarg(long) bufsize;
215 		syscallarg(int) flags;
216 	} */
217 	int root = 0;
218 	mount_iterator_t *iter;
219 	struct mount *mp;
220 	struct statvfs *sbuf;
221 	struct statfs12 *sfsp;
222 	size_t count, maxcount;
223 	int error = 0;
224 
225 	sbuf = malloc(sizeof(*sbuf), M_TEMP, M_WAITOK);
226 	maxcount = (size_t)SCARG(uap, bufsize) / sizeof(struct statfs12);
227 	sfsp = SCARG(uap, buf);
228 	count = 0;
229 	mountlist_iterator_init(&iter);
230 	while ((mp = mountlist_iterator_next(iter)) != NULL) {
231 		if (sfsp && count < maxcount) {
232 			error = dostatvfs(mp, sbuf, l, SCARG(uap, flags), 0);
233 			if (error)
234 				continue;
235 			error = vfs2fs(sfsp, sbuf);
236 			if (error)
237 				goto out;
238 			sfsp++;
239 			root |= strcmp(sbuf->f_mntonname, "/") == 0;
240 		}
241 		count++;
242 	}
243 	if (root == 0 && l->l_proc->p_cwdi->cwdi_rdir) {
244 		/*
245 		 * fake a root entry
246 		 */
247 		if ((error = dostatvfs(l->l_proc->p_cwdi->cwdi_rdir->v_mount,
248 				       sbuf, l, SCARG(uap, flags), 1)) != 0)
249 			goto out;
250 		if (sfsp)
251 			error = vfs2fs(sfsp, sbuf);
252 		count++;
253 	}
254 	if (sfsp && count > maxcount)
255 		*retval = maxcount;
256 	else
257 		*retval = count;
258 out:
259 	mountlist_iterator_destroy(iter);
260 	free(sbuf, M_TEMP);
261 	return error;
262 }
263 
264 int
265 compat_20_sys_fhstatfs(struct lwp *l, const struct compat_20_sys_fhstatfs_args *uap, register_t *retval)
266 {
267 	/* {
268 		syscallarg(const struct compat_30_fhandle *) fhp;
269 		syscallarg(struct statfs12 *) buf;
270 	} */
271 	struct statvfs *sbuf;
272 	struct compat_30_fhandle fh;
273 	struct mount *mp;
274 	struct vnode *vp;
275 	int error;
276 
277 	/*
278 	 * Must be super user
279 	 */
280 	if ((error = kauth_authorize_system(l->l_cred,
281 	    KAUTH_SYSTEM_FILEHANDLE, 0, NULL, NULL, NULL)))
282 		return (error);
283 
284 	if ((error = copyin(SCARG(uap, fhp), &fh, sizeof(fh))) != 0)
285 		return (error);
286 
287 	if ((mp = vfs_getvfs(&fh.fh_fsid)) == NULL)
288 		return (ESTALE);
289 	if ((error = VFS_FHTOVP(mp, (struct fid*)&fh.fh_fid, &vp)))
290 		return (error);
291 	mp = vp->v_mount;
292 	VOP_UNLOCK(vp);
293 	sbuf = malloc(sizeof(*sbuf), M_TEMP, M_WAITOK);
294 	if ((error = VFS_STATVFS(mp, sbuf)) != 0)
295 		goto out;
296 	error = vfs2fs(SCARG(uap, buf), sbuf);
297 out:
298 	vrele(vp);
299 	free(sbuf, M_TEMP);
300 	return error;
301 }
302 
303 int
304 vfs_syscalls_20_init(void)
305 {
306 
307 	return syscall_establish(NULL, vfs_syscalls_20_syscalls);
308 }
309 
310 int
311 vfs_syscalls_20_fini(void)
312 {
313 
314 	return syscall_disestablish(NULL, vfs_syscalls_20_syscalls);
315 }
316