aboutsummaryrefslogtreecommitdiffstats
path: root/fs/ocfs2/acl.c
blob: c58a1bcfda0fdfa83f2a42169eb308580c759def (plain) (blame)
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
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
/* -*- mode: c; c-basic-offset: 8; -*-
 * vim: noexpandtab sw=8 ts=8 sts=0:
 *
 * acl.c
 *
 * Copyright (C) 2004, 2008 Oracle.  All rights reserved.
 *
 * CREDITS:
 * Lots of code in this file is copy from linux/fs/ext3/acl.c.
 * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
 *
 * 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.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/string.h>

#include <cluster/masklog.h>

#include "ocfs2.h"
#include "alloc.h"
#include "dlmglue.h"
#include "file.h"
#include "inode.h"
#include "journal.h"
#include "ocfs2_fs.h"

#include "xattr.h"
#include "acl.h"

/*
 * Convert from xattr value to acl struct.
 */
static struct posix_acl *ocfs2_acl_from_xattr(const void *value, size_t size)
{
	int n, count;
	struct posix_acl *acl;

	if (!value)
		return NULL;
	if (size < sizeof(struct posix_acl_entry))
		return ERR_PTR(-EINVAL);

	count = size / sizeof(struct posix_acl_entry);

	acl = posix_acl_alloc(count, GFP_NOFS);
	if (!acl)
		return ERR_PTR(-ENOMEM);
	for (n = 0; n < count; n++) {
		struct ocfs2_acl_entry *entry =
			(struct ocfs2_acl_entry *)value;

		acl->a_entries[n].e_tag  = le16_to_cpu(entry->e_tag);
		acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
		switch(acl->a_entries[n].e_tag) {
		case ACL_USER:
			acl->a_entries[n].e_uid =
				make_kuid(&init_user_ns,
					  le32_to_cpu(entry->e_id));
			break;
		case ACL_GROUP:
			acl->a_entries[n].e_gid =
				make_kgid(&init_user_ns,
					  le32_to_cpu(entry->e_id));
			break;
		default:
			break;
		}
		value += sizeof(struct posix_acl_entry);

	}
	return acl;
}

/*
 * Convert acl struct to xattr value.
 */
static void *ocfs2_acl_to_xattr(const struct posix_acl *acl, size_t *size)
{
	struct ocfs2_acl_entry *entry = NULL;
	char *ocfs2_acl;
	size_t n;

	*size = acl->a_count * sizeof(struct posix_acl_entry);

	ocfs2_acl = kmalloc(*size, GFP_NOFS);
	if (!ocfs2_acl)
		return ERR_PTR(-ENOMEM);

	entry = (struct ocfs2_acl_entry *)ocfs2_acl;
	for (n = 0; n < acl->a_count; n++, entry++) {
		entry->e_tag  = cpu_to_le16(acl->a_entries[n].e_tag);
		entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
		switch(acl->a_entries[n].e_tag) {
		case ACL_USER:
			entry->e_id = cpu_to_le32(
				from_kuid(&init_user_ns,
					  acl->a_entries[n].e_uid));
			break;
		case ACL_GROUP:
			entry->e_id = cpu_to_le32(
				from_kgid(&init_user_ns,
					  acl->a_entries[n].e_gid));
			break;
		default:
			entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
			break;
		}
	}
	return ocfs2_acl;
}

static struct posix_acl *ocfs2_get_acl_nolock(struct inode *inode,
					      int type,
					      struct buffer_head *di_bh)
{
	int name_index;
	char *value = NULL;
	struct posix_acl *acl;
	int retval;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
		break;
	default:
		return ERR_PTR(-EINVAL);
	}

	retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index, "", NULL, 0);
	if (retval > 0) {
		value = kmalloc(retval, GFP_NOFS);
		if (!value)
			return ERR_PTR(-ENOMEM);
		retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index,
						"", value, retval);
	}

	if (retval > 0)
		acl = ocfs2_acl_from_xattr(value, retval);
	else if (retval == -ENODATA || retval == 0)
		acl = NULL;
	else
		acl = ERR_PTR(retval);

	kfree(value);

	return acl;
}

/*
 * Helper function to set i_mode in memory and disk. Some call paths
 * will not have di_bh or a journal handle to pass, in which case it
 * will create it's own.
 */
static int ocfs2_acl_set_mode(struct inode *inode, struct buffer_head *di_bh,
			      handle_t *handle, umode_t new_mode)
{
	int ret, commit_handle = 0;
	struct ocfs2_dinode *di;

	if (di_bh == NULL) {
		ret = ocfs2_read_inode_block(inode, &di_bh);
		if (ret) {
			mlog_errno(ret);
			goto out;
		}
	} else
		get_bh(di_bh);

	if (handle == NULL) {
		handle = ocfs2_start_trans(OCFS2_SB(inode->i_sb),
					   OCFS2_INODE_UPDATE_CREDITS);
		if (IS_ERR(handle)) {
			ret = PTR_ERR(handle);
			mlog_errno(ret);
			goto out_brelse;
		}

		commit_handle = 1;
	}

	di = (struct ocfs2_dinode *)di_bh->b_data;
	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
				      OCFS2_JOURNAL_ACCESS_WRITE);
	if (ret) {
		mlog_errno(ret);
		goto out_commit;
	}

	inode->i_mode = new_mode;
	inode->i_ctime = CURRENT_TIME;
	di->i_mode = cpu_to_le16(inode->i_mode);
	di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
	di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
	ocfs2_update_inode_fsync_trans(handle, inode, 0);

	ocfs2_journal_dirty(handle, di_bh);

out_commit:
	if (commit_handle)
		ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
out_brelse:
	brelse(di_bh);
out:
	return ret;
}

/*
 * Set the access or default ACL of an inode.
 */
int ocfs2_set_acl(handle_t *handle,
			 struct inode *inode,
			 struct buffer_head *di_bh,
			 int type,
			 struct posix_acl *acl,
			 struct ocfs2_alloc_context *meta_ac,
			 struct ocfs2_alloc_context *data_ac)
{
	int name_index;
	void *value = NULL;
	size_t size = 0;
	int ret;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
		if (acl) {
			umode_t mode = inode->i_mode;
			ret = posix_acl_equiv_mode(acl, &mode);
			if (ret < 0)
				return ret;

			if (ret == 0)
				acl = NULL;

			ret = ocfs2_acl_set_mode(inode, di_bh,
						 handle, mode);
			if (ret)
				return ret;
		}
		break;
	case ACL_TYPE_DEFAULT:
		name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
		if (!S_ISDIR(inode->i_mode))
			return acl ? -EACCES : 0;
		break;
	default:
		return -EINVAL;
	}

	if (acl) {
		value = ocfs2_acl_to_xattr(acl, &size);
		if (IS_ERR(value))
			return (int)PTR_ERR(value);
	}

	if (handle)
		ret = ocfs2_xattr_set_handle(handle, inode, di_bh, name_index,
					     "", value, size, 0,
					     meta_ac, data_ac);
	else
		ret = ocfs2_xattr_set(inode, name_index, "", value, size, 0);

	kfree(value);

	return ret;
}

int ocfs2_iop_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
	return ocfs2_set_acl(NULL, inode, NULL, type, acl, NULL, NULL);
}

struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type)
{
	struct ocfs2_super *osb;
	struct buffer_head *di_bh = NULL;
	struct posix_acl *acl;
	int ret = -EAGAIN;

	osb = OCFS2_SB(inode->i_sb);
	if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
		return NULL;

	ret = ocfs2_read_inode_block(inode, &di_bh);
	if (ret < 0)
		return ERR_PTR(ret);

	acl = ocfs2_get_acl_nolock(inode, type, di_bh);

	brelse(di_bh);

	return acl;
}