1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * acl.c
5 *
6 * Copyright (C) 2004, 2008 Oracle. All rights reserved.
7 *
8 * CREDITS:
9 * Lots of code in this file is copy from linux/fs/ext3/acl.c.
10 * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public
14 * License version 2 as published by the Free Software Foundation.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
20 */
21
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/slab.h>
25 #include <linux/string.h>
26
27 #include <cluster/masklog.h>
28
29 #include "ocfs2.h"
30 #include "alloc.h"
31 #include "dlmglue.h"
32 #include "file.h"
33 #include "inode.h"
34 #include "journal.h"
35 #include "ocfs2_fs.h"
36
37 #include "xattr.h"
38 #include "acl.h"
39
40 /*
41 * Convert from xattr value to acl struct.
42 */
ocfs2_acl_from_xattr(const void * value,size_t size)43 static struct posix_acl *ocfs2_acl_from_xattr(const void *value, size_t size)
44 {
45 int n, count;
46 struct posix_acl *acl;
47
48 if (!value)
49 return NULL;
50 if (size < sizeof(struct posix_acl_entry))
51 return ERR_PTR(-EINVAL);
52
53 count = size / sizeof(struct posix_acl_entry);
54
55 acl = posix_acl_alloc(count, GFP_NOFS);
56 if (!acl)
57 return ERR_PTR(-ENOMEM);
58 for (n = 0; n < count; n++) {
59 struct ocfs2_acl_entry *entry =
60 (struct ocfs2_acl_entry *)value;
61
62 acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
63 acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
64 switch(acl->a_entries[n].e_tag) {
65 case ACL_USER:
66 acl->a_entries[n].e_uid =
67 make_kuid(&init_user_ns,
68 le32_to_cpu(entry->e_id));
69 break;
70 case ACL_GROUP:
71 acl->a_entries[n].e_gid =
72 make_kgid(&init_user_ns,
73 le32_to_cpu(entry->e_id));
74 break;
75 default:
76 break;
77 }
78 value += sizeof(struct posix_acl_entry);
79
80 }
81 return acl;
82 }
83
84 /*
85 * Convert acl struct to xattr value.
86 */
ocfs2_acl_to_xattr(const struct posix_acl * acl,size_t * size)87 static void *ocfs2_acl_to_xattr(const struct posix_acl *acl, size_t *size)
88 {
89 struct ocfs2_acl_entry *entry = NULL;
90 char *ocfs2_acl;
91 size_t n;
92
93 *size = acl->a_count * sizeof(struct posix_acl_entry);
94
95 ocfs2_acl = kmalloc(*size, GFP_NOFS);
96 if (!ocfs2_acl)
97 return ERR_PTR(-ENOMEM);
98
99 entry = (struct ocfs2_acl_entry *)ocfs2_acl;
100 for (n = 0; n < acl->a_count; n++, entry++) {
101 entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
102 entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
103 switch(acl->a_entries[n].e_tag) {
104 case ACL_USER:
105 entry->e_id = cpu_to_le32(
106 from_kuid(&init_user_ns,
107 acl->a_entries[n].e_uid));
108 break;
109 case ACL_GROUP:
110 entry->e_id = cpu_to_le32(
111 from_kgid(&init_user_ns,
112 acl->a_entries[n].e_gid));
113 break;
114 default:
115 entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
116 break;
117 }
118 }
119 return ocfs2_acl;
120 }
121
ocfs2_get_acl_nolock(struct inode * inode,int type,struct buffer_head * di_bh)122 static struct posix_acl *ocfs2_get_acl_nolock(struct inode *inode,
123 int type,
124 struct buffer_head *di_bh)
125 {
126 int name_index;
127 char *value = NULL;
128 struct posix_acl *acl;
129 int retval;
130
131 switch (type) {
132 case ACL_TYPE_ACCESS:
133 name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
134 break;
135 case ACL_TYPE_DEFAULT:
136 name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
137 break;
138 default:
139 return ERR_PTR(-EINVAL);
140 }
141
142 retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index, "", NULL, 0);
143 if (retval > 0) {
144 value = kmalloc(retval, GFP_NOFS);
145 if (!value)
146 return ERR_PTR(-ENOMEM);
147 retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index,
148 "", value, retval);
149 }
150
151 if (retval > 0)
152 acl = ocfs2_acl_from_xattr(value, retval);
153 else if (retval == -ENODATA || retval == 0)
154 acl = NULL;
155 else
156 acl = ERR_PTR(retval);
157
158 kfree(value);
159
160 return acl;
161 }
162
163 /*
164 * Helper function to set i_mode in memory and disk. Some call paths
165 * will not have di_bh or a journal handle to pass, in which case it
166 * will create it's own.
167 */
ocfs2_acl_set_mode(struct inode * inode,struct buffer_head * di_bh,handle_t * handle,umode_t new_mode)168 static int ocfs2_acl_set_mode(struct inode *inode, struct buffer_head *di_bh,
169 handle_t *handle, umode_t new_mode)
170 {
171 int ret, commit_handle = 0;
172 struct ocfs2_dinode *di;
173
174 if (di_bh == NULL) {
175 ret = ocfs2_read_inode_block(inode, &di_bh);
176 if (ret) {
177 mlog_errno(ret);
178 goto out;
179 }
180 } else
181 get_bh(di_bh);
182
183 if (handle == NULL) {
184 handle = ocfs2_start_trans(OCFS2_SB(inode->i_sb),
185 OCFS2_INODE_UPDATE_CREDITS);
186 if (IS_ERR(handle)) {
187 ret = PTR_ERR(handle);
188 mlog_errno(ret);
189 goto out_brelse;
190 }
191
192 commit_handle = 1;
193 }
194
195 di = (struct ocfs2_dinode *)di_bh->b_data;
196 ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
197 OCFS2_JOURNAL_ACCESS_WRITE);
198 if (ret) {
199 mlog_errno(ret);
200 goto out_commit;
201 }
202
203 inode->i_mode = new_mode;
204 inode->i_ctime = CURRENT_TIME;
205 di->i_mode = cpu_to_le16(inode->i_mode);
206 di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
207 di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
208 ocfs2_update_inode_fsync_trans(handle, inode, 0);
209
210 ocfs2_journal_dirty(handle, di_bh);
211
212 out_commit:
213 if (commit_handle)
214 ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
215 out_brelse:
216 brelse(di_bh);
217 out:
218 return ret;
219 }
220
221 /*
222 * Set the access or default ACL of an inode.
223 */
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)224 int ocfs2_set_acl(handle_t *handle,
225 struct inode *inode,
226 struct buffer_head *di_bh,
227 int type,
228 struct posix_acl *acl,
229 struct ocfs2_alloc_context *meta_ac,
230 struct ocfs2_alloc_context *data_ac)
231 {
232 int name_index;
233 void *value = NULL;
234 size_t size = 0;
235 int ret;
236
237 if (S_ISLNK(inode->i_mode))
238 return -EOPNOTSUPP;
239
240 switch (type) {
241 case ACL_TYPE_ACCESS:
242 name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
243 if (acl) {
244 umode_t mode = inode->i_mode;
245 ret = posix_acl_equiv_mode(acl, &mode);
246 if (ret < 0)
247 return ret;
248
249 if (ret == 0)
250 acl = NULL;
251
252 ret = ocfs2_acl_set_mode(inode, di_bh,
253 handle, mode);
254 if (ret)
255 return ret;
256 }
257 break;
258 case ACL_TYPE_DEFAULT:
259 name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
260 if (!S_ISDIR(inode->i_mode))
261 return acl ? -EACCES : 0;
262 break;
263 default:
264 return -EINVAL;
265 }
266
267 if (acl) {
268 value = ocfs2_acl_to_xattr(acl, &size);
269 if (IS_ERR(value))
270 return (int)PTR_ERR(value);
271 }
272
273 if (handle)
274 ret = ocfs2_xattr_set_handle(handle, inode, di_bh, name_index,
275 "", value, size, 0,
276 meta_ac, data_ac);
277 else
278 ret = ocfs2_xattr_set(inode, name_index, "", value, size, 0);
279
280 kfree(value);
281
282 return ret;
283 }
284
ocfs2_iop_set_acl(struct inode * inode,struct posix_acl * acl,int type)285 int ocfs2_iop_set_acl(struct inode *inode, struct posix_acl *acl, int type)
286 {
287 return ocfs2_set_acl(NULL, inode, NULL, type, acl, NULL, NULL);
288 }
289
ocfs2_iop_get_acl(struct inode * inode,int type)290 struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type)
291 {
292 struct ocfs2_super *osb;
293 struct buffer_head *di_bh = NULL;
294 struct posix_acl *acl;
295 int ret = -EAGAIN;
296
297 osb = OCFS2_SB(inode->i_sb);
298 if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
299 return NULL;
300
301 ret = ocfs2_read_inode_block(inode, &di_bh);
302 if (ret < 0)
303 return ERR_PTR(ret);
304
305 acl = ocfs2_get_acl_nolock(inode, type, di_bh);
306
307 brelse(di_bh);
308
309 return acl;
310 }
311
ocfs2_acl_chmod(struct inode * inode,struct buffer_head * bh)312 int ocfs2_acl_chmod(struct inode *inode, struct buffer_head *bh)
313 {
314 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
315 struct posix_acl *acl;
316 int ret;
317
318 if (S_ISLNK(inode->i_mode))
319 return -EOPNOTSUPP;
320
321 if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
322 return 0;
323
324 acl = ocfs2_get_acl_nolock(inode, ACL_TYPE_ACCESS, bh);
325 if (IS_ERR(acl) || !acl)
326 return PTR_ERR(acl);
327 ret = __posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
328 if (ret)
329 return ret;
330 ret = ocfs2_set_acl(NULL, inode, NULL, ACL_TYPE_ACCESS,
331 acl, NULL, NULL);
332 posix_acl_release(acl);
333 return ret;
334 }
335
336 /*
337 * Initialize the ACLs of a new inode. If parent directory has default ACL,
338 * then clone to new inode. Called from ocfs2_mknod.
339 */
ocfs2_init_acl(handle_t * handle,struct inode * inode,struct inode * dir,struct buffer_head * di_bh,struct buffer_head * dir_bh,struct ocfs2_alloc_context * meta_ac,struct ocfs2_alloc_context * data_ac)340 int ocfs2_init_acl(handle_t *handle,
341 struct inode *inode,
342 struct inode *dir,
343 struct buffer_head *di_bh,
344 struct buffer_head *dir_bh,
345 struct ocfs2_alloc_context *meta_ac,
346 struct ocfs2_alloc_context *data_ac)
347 {
348 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
349 struct posix_acl *acl = NULL;
350 int ret = 0, ret2;
351 umode_t mode;
352
353 if (!S_ISLNK(inode->i_mode)) {
354 if (osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) {
355 acl = ocfs2_get_acl_nolock(dir, ACL_TYPE_DEFAULT,
356 dir_bh);
357 if (IS_ERR(acl))
358 return PTR_ERR(acl);
359 }
360 if (!acl) {
361 mode = inode->i_mode & ~current_umask();
362 ret = ocfs2_acl_set_mode(inode, di_bh, handle, mode);
363 if (ret) {
364 mlog_errno(ret);
365 goto cleanup;
366 }
367 }
368 }
369 if ((osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) && acl) {
370 if (S_ISDIR(inode->i_mode)) {
371 ret = ocfs2_set_acl(handle, inode, di_bh,
372 ACL_TYPE_DEFAULT, acl,
373 meta_ac, data_ac);
374 if (ret)
375 goto cleanup;
376 }
377 mode = inode->i_mode;
378 ret = __posix_acl_create(&acl, GFP_NOFS, &mode);
379 if (ret < 0)
380 return ret;
381
382 ret2 = ocfs2_acl_set_mode(inode, di_bh, handle, mode);
383 if (ret2) {
384 mlog_errno(ret2);
385 ret = ret2;
386 goto cleanup;
387 }
388 if (ret > 0) {
389 ret = ocfs2_set_acl(handle, inode,
390 di_bh, ACL_TYPE_ACCESS,
391 acl, meta_ac, data_ac);
392 }
393 }
394 cleanup:
395 posix_acl_release(acl);
396 return ret;
397 }
398