1 /*
2 * Copyright (C) International Business Machines Corp., 2002-2004
3 * Copyright (C) Andreas Gruenbacher, 2001
4 * Copyright (C) Linus Torvalds, 1991, 1992
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
14 * the GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21 #include <linux/sched.h>
22 #include <linux/slab.h>
23 #include <linux/fs.h>
24 #include <linux/posix_acl_xattr.h>
25 #include "jfs_incore.h"
26 #include "jfs_txnmgr.h"
27 #include "jfs_xattr.h"
28 #include "jfs_acl.h"
29
jfs_get_acl(struct inode * inode,int type)30 static struct posix_acl *jfs_get_acl(struct inode *inode, int type)
31 {
32 struct posix_acl *acl;
33 char *ea_name;
34 int size;
35 char *value = NULL;
36
37 acl = get_cached_acl(inode, type);
38 if (acl != ACL_NOT_CACHED)
39 return acl;
40
41 switch(type) {
42 case ACL_TYPE_ACCESS:
43 ea_name = POSIX_ACL_XATTR_ACCESS;
44 break;
45 case ACL_TYPE_DEFAULT:
46 ea_name = POSIX_ACL_XATTR_DEFAULT;
47 break;
48 default:
49 return ERR_PTR(-EINVAL);
50 }
51
52 size = __jfs_getxattr(inode, ea_name, NULL, 0);
53
54 if (size > 0) {
55 value = kmalloc(size, GFP_KERNEL);
56 if (!value)
57 return ERR_PTR(-ENOMEM);
58 size = __jfs_getxattr(inode, ea_name, value, size);
59 }
60
61 if (size < 0) {
62 if (size == -ENODATA)
63 acl = NULL;
64 else
65 acl = ERR_PTR(size);
66 } else {
67 acl = posix_acl_from_xattr(value, size);
68 }
69 kfree(value);
70 if (!IS_ERR(acl))
71 set_cached_acl(inode, type, acl);
72 return acl;
73 }
74
jfs_set_acl(tid_t tid,struct inode * inode,int type,struct posix_acl * acl)75 static int jfs_set_acl(tid_t tid, struct inode *inode, int type,
76 struct posix_acl *acl)
77 {
78 char *ea_name;
79 int rc;
80 int size = 0;
81 char *value = NULL;
82
83 if (S_ISLNK(inode->i_mode))
84 return -EOPNOTSUPP;
85
86 switch(type) {
87 case ACL_TYPE_ACCESS:
88 ea_name = POSIX_ACL_XATTR_ACCESS;
89 break;
90 case ACL_TYPE_DEFAULT:
91 ea_name = POSIX_ACL_XATTR_DEFAULT;
92 if (!S_ISDIR(inode->i_mode))
93 return acl ? -EACCES : 0;
94 break;
95 default:
96 return -EINVAL;
97 }
98 if (acl) {
99 size = posix_acl_xattr_size(acl->a_count);
100 value = kmalloc(size, GFP_KERNEL);
101 if (!value)
102 return -ENOMEM;
103 rc = posix_acl_to_xattr(acl, value, size);
104 if (rc < 0)
105 goto out;
106 }
107 rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0);
108 out:
109 kfree(value);
110
111 if (!rc)
112 set_cached_acl(inode, type, acl);
113
114 return rc;
115 }
116
jfs_check_acl(struct inode * inode,int mask,unsigned int flags)117 int jfs_check_acl(struct inode *inode, int mask, unsigned int flags)
118 {
119 struct posix_acl *acl;
120
121 if (flags & IPERM_FLAG_RCU)
122 return -ECHILD;
123
124 acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
125 if (IS_ERR(acl))
126 return PTR_ERR(acl);
127 if (acl) {
128 int error = posix_acl_permission(inode, acl, mask);
129 posix_acl_release(acl);
130 return error;
131 }
132
133 return -EAGAIN;
134 }
135
jfs_init_acl(tid_t tid,struct inode * inode,struct inode * dir)136 int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
137 {
138 struct posix_acl *acl = NULL;
139 struct posix_acl *clone;
140 mode_t mode;
141 int rc = 0;
142
143 if (S_ISLNK(inode->i_mode))
144 return 0;
145
146 acl = jfs_get_acl(dir, ACL_TYPE_DEFAULT);
147 if (IS_ERR(acl))
148 return PTR_ERR(acl);
149
150 if (acl) {
151 if (S_ISDIR(inode->i_mode)) {
152 rc = jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, acl);
153 if (rc)
154 goto cleanup;
155 }
156 clone = posix_acl_clone(acl, GFP_KERNEL);
157 if (!clone) {
158 rc = -ENOMEM;
159 goto cleanup;
160 }
161 mode = inode->i_mode;
162 rc = posix_acl_create_masq(clone, &mode);
163 if (rc >= 0) {
164 inode->i_mode = mode;
165 if (rc > 0)
166 rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS,
167 clone);
168 }
169 posix_acl_release(clone);
170 cleanup:
171 posix_acl_release(acl);
172 } else
173 inode->i_mode &= ~current_umask();
174
175 JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
176 inode->i_mode;
177
178 return rc;
179 }
180
jfs_acl_chmod(struct inode * inode)181 int jfs_acl_chmod(struct inode *inode)
182 {
183 struct posix_acl *acl, *clone;
184 int rc;
185
186 if (S_ISLNK(inode->i_mode))
187 return -EOPNOTSUPP;
188
189 acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
190 if (IS_ERR(acl) || !acl)
191 return PTR_ERR(acl);
192
193 clone = posix_acl_clone(acl, GFP_KERNEL);
194 posix_acl_release(acl);
195 if (!clone)
196 return -ENOMEM;
197
198 rc = posix_acl_chmod_masq(clone, inode->i_mode);
199 if (!rc) {
200 tid_t tid = txBegin(inode->i_sb, 0);
201 mutex_lock(&JFS_IP(inode)->commit_mutex);
202 rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, clone);
203 if (!rc)
204 rc = txCommit(tid, 1, &inode, 0);
205 txEnd(tid);
206 mutex_unlock(&JFS_IP(inode)->commit_mutex);
207 }
208
209 posix_acl_release(clone);
210 return rc;
211 }
212