summaryrefslogtreecommitdiffstats
path: root/fs/ubifs/ioctl.c
blob: 12b9eb5005ff07461e430fffb2526fb08aa9f790 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
/*
 * This file is part of UBIFS.
 *
 * Copyright (C) 2006-2008 Nokia Corporation.
 * Copyright (C) 2006, 2007 University of Szeged, Hungary
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * Authors: Zoltan Sogor
 *          Artem Bityutskiy (Битюцкий Артём)
 *          Adrian Hunter
 */

/* This file implements EXT2-compatible extended attribute ioctl() calls */

#include <linux/compat.h>
#include <linux/mount.h>
#include "ubifs.h"

/**
 * ubifs_set_inode_flags - set VFS inode flags.
 * @inode: VFS inode to set flags for
 *
 * This function propagates flags from UBIFS inode object to VFS inode object.
 */
void ubifs_set_inode_flags(struct inode *inode)
{
	unsigned int flags = ubifs_inode(inode)->flags;

	inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_DIRSYNC);
	if (flags & UBIFS_SYNC_FL)
		inode->i_flags |= S_SYNC;
	if (flags & UBIFS_APPEND_FL)
		inode->i_flags |= S_APPEND;
	if (flags & UBIFS_IMMUTABLE_FL)
		inode->i_flags |= S_IMMUTABLE;
	if (flags & UBIFS_DIRSYNC_FL)
		inode->i_flags |= S_DIRSYNC;
}

/*
 * ioctl2ubifs - convert ioctl inode flags to UBIFS inode flags.
 * @ioctl_flags: flags to convert
 *
 * This function convert ioctl flags (@FS_COMPR_FL, etc) to UBIFS inode flags
 * (@UBIFS_COMPR_FL, etc).
 */
static int ioctl2ubifs(int ioctl_flags)
{
	int ubifs_flags = 0;

	if (ioctl_flags & FS_COMPR_FL)
		ubifs_flags |= UBIFS_COMPR_FL;
	if (ioctl_flags & FS_SYNC_FL)
		ubifs_flags |= UBIFS_SYNC_FL;
	if (ioctl_flags & FS_APPEND_FL)
		ubifs_flags |= UBIFS_APPEND_FL;
	if (ioctl_flags & FS_IMMUTABLE_FL)
		ubifs_flags |= UBIFS_IMMUTABLE_FL;
	if (ioctl_flags & FS_DIRSYNC_FL)
		ubifs_flags |= UBIFS_DIRSYNC_FL;

	return ubifs_flags;
}

/*
 * ubifs2ioctl - convert UBIFS inode flags to ioctl inode flags.
 * @ubifs_flags: flags to convert
 *
 * This function convert UBIFS (@UBIFS_COMPR_FL, etc) to ioctl flags
 * (@FS_COMPR_FL, etc).
 */
static int ubifs2ioctl(int ubifs_flags)
{
	int ioctl_flags = 0;

	if (ubifs_flags & UBIFS_COMPR_FL)
		ioctl_flags |= FS_COMPR_FL;
	if (ubifs_flags & UBIFS_SYNC_FL)
		ioctl_flags |= FS_SYNC_FL;
	if (ubifs_flags & UBIFS_APPEND_FL)
		ioctl_flags |= FS_APPEND_FL;
	if (ubifs_flags & UBIFS_IMMUTABLE_FL)
		ioctl_flags |= FS_IMMUTABLE_FL;
	if (ubifs_flags & UBIFS_DIRSYNC_FL)
		ioctl_flags |= FS_DIRSYNC_FL;

	return ioctl_flags;
}

static int setflags(struct inode *inode, int flags)
{
	int oldflags, err, release;
	struct ubifs_inode *ui = ubifs_inode(inode);
	struct ubifs_info *c = inode->i_sb->s_fs_info;
	struct ubifs_budget_req req = { .dirtied_ino = 1,
					.dirtied_ino_d = ui->data_len };

	err = ubifs_budget_space(c, &req);
	if (err)
		return err;

	/*
	 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
	 * the relevant capability.
	 */
	mutex_lock(&ui->ui_mutex);
	oldflags = ubifs2ioctl(ui->flags);
	if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
		if (!capable(CAP_LINUX_IMMUTABLE)) {
			err = -EPERM;
			goto out_unlock;
		}
	}

	ui->flags = ioctl2ubifs(flags);
	ubifs_set_inode_flags(inode);
	inode->i_ctime = current_time(inode);
	release = ui->dirty;
	mark_inode_dirty_sync(inode);
	mutex_unlock(&ui->ui_mutex);

	if (release)
		ubifs_release_budget(c, &req);
	if (IS_SYNC(inode))
		err = write_inode_now(inode, 1);
	return err;

out_unlock:
	ubifs_err(c, "can't modify inode %lu attributes", inode->i_ino);
	mutex_unlock(&ui->ui_mutex);
	ubifs_release_budget(c, &req);
	return err;
}

long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	int flags, err;
	struct inode *inode = file_inode(file);

	switch (cmd) {
	case FS_IOC_GETFLAGS:
		flags = ubifs2ioctl(ubifs_inode(inode)->flags);

		dbg_gen("get flags: %#x, i_flags %#x", flags, inode->i_flags);
		return put_user(flags, (int __user *) arg);

	case FS_IOC_SETFLAGS: {
		if (IS_RDONLY(inode))
			return -EROFS;

		if (!inode_owner_or_capable(inode))
			return -EACCES;

		if (get_user(flags, (int __user *) arg))
			return -EFAULT;

		if (!S_ISDIR(inode->i_mode))
			flags &= ~FS_DIRSYNC_FL;

		/*
		 * Make sure the file-system is read-write and make sure it
		 * will not become read-only while we are changing the flags.
		 */
		err = mnt_want_write_file(file);
		if (err)
			return err;
		dbg_gen("set flags: %#x, i_flags %#x", flags, inode->i_flags);
		err = setflags(inode, flags);
		mnt_drop_write_file(file);
		return err;
	}
	case FS_IOC_SET_ENCRYPTION_POLICY: {
#ifdef CONFIG_UBIFS_FS_ENCRYPTION
		struct ubifs_info *c = inode->i_sb->s_fs_info;

		err = ubifs_enable_encryption(c);
		if (err)
			return err;

		return fscrypt_ioctl_set_policy(file, (const void __user *)arg);
#else
		return -EOPNOTSUPP;
#endif
	}
	case FS_IOC_GET_ENCRYPTION_POLICY: {
#ifdef CONFIG_UBIFS_FS_ENCRYPTION
		return fscrypt_ioctl_get_policy(file, (void __user *)arg);
#else
		return -EOPNOTSUPP;
#endif
	}

	default:
		return -ENOTTY;
	}
}

#ifdef CONFIG_COMPAT
long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	switch (cmd) {
	case FS_IOC32_GETFLAGS:
		cmd = FS_IOC_GETFLAGS;
		break;
	case FS_IOC32_SETFLAGS:
		cmd = FS_IOC_SETFLAGS;
		break;
	case FS_IOC_SET_ENCRYPTION_POLICY:
	case FS_IOC_GET_ENCRYPTION_POLICY:
		break;
	default:
		return -ENOIOCTLCMD;
	}
	return ubifs_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
}
#endif