Commit | Line | Data |
---|---|---|
f0c8bd16 | 1 | /* |
f0c8bd16 AG |
2 | * (C) 2005 Andreas Gruenbacher <agruen@suse.de> |
3 | * | |
4 | * This file is released under the GPL. | |
1c7c474c CH |
5 | * |
6 | * Generic ACL support for in-memory filesystems. | |
f0c8bd16 AG |
7 | */ |
8 | ||
9 | #include <linux/sched.h> | |
5a0e3ad6 | 10 | #include <linux/gfp.h> |
f0c8bd16 AG |
11 | #include <linux/fs.h> |
12 | #include <linux/generic_acl.h> | |
1c7c474c CH |
13 | #include <linux/posix_acl.h> |
14 | #include <linux/posix_acl_xattr.h> | |
f0c8bd16 | 15 | |
1c7c474c CH |
16 | |
17 | static size_t | |
18 | generic_acl_list(struct dentry *dentry, char *list, size_t list_size, | |
19 | const char *name, size_t name_len, int type) | |
f0c8bd16 AG |
20 | { |
21 | struct posix_acl *acl; | |
1c7c474c | 22 | const char *xname; |
f0c8bd16 AG |
23 | size_t size; |
24 | ||
1c7c474c | 25 | acl = get_cached_acl(dentry->d_inode, type); |
f0c8bd16 AG |
26 | if (!acl) |
27 | return 0; | |
28 | posix_acl_release(acl); | |
29 | ||
1c7c474c CH |
30 | switch (type) { |
31 | case ACL_TYPE_ACCESS: | |
32 | xname = POSIX_ACL_XATTR_ACCESS; | |
33 | break; | |
34 | case ACL_TYPE_DEFAULT: | |
35 | xname = POSIX_ACL_XATTR_DEFAULT; | |
36 | break; | |
37 | default: | |
38 | return 0; | |
f0c8bd16 | 39 | } |
1c7c474c | 40 | size = strlen(xname) + 1; |
f0c8bd16 | 41 | if (list && size <= list_size) |
1c7c474c | 42 | memcpy(list, xname, size); |
f0c8bd16 AG |
43 | return size; |
44 | } | |
45 | ||
1c7c474c CH |
46 | static int |
47 | generic_acl_get(struct dentry *dentry, const char *name, void *buffer, | |
48 | size_t size, int type) | |
f0c8bd16 AG |
49 | { |
50 | struct posix_acl *acl; | |
51 | int error; | |
52 | ||
1c7c474c CH |
53 | if (strcmp(name, "") != 0) |
54 | return -EINVAL; | |
55 | ||
56 | acl = get_cached_acl(dentry->d_inode, type); | |
f0c8bd16 AG |
57 | if (!acl) |
58 | return -ENODATA; | |
59 | error = posix_acl_to_xattr(acl, buffer, size); | |
60 | posix_acl_release(acl); | |
61 | ||
62 | return error; | |
63 | } | |
64 | ||
1c7c474c CH |
65 | static int |
66 | generic_acl_set(struct dentry *dentry, const char *name, const void *value, | |
67 | size_t size, int flags, int type) | |
f0c8bd16 | 68 | { |
1c7c474c | 69 | struct inode *inode = dentry->d_inode; |
f0c8bd16 AG |
70 | struct posix_acl *acl = NULL; |
71 | int error; | |
72 | ||
1c7c474c CH |
73 | if (strcmp(name, "") != 0) |
74 | return -EINVAL; | |
f0c8bd16 AG |
75 | if (S_ISLNK(inode->i_mode)) |
76 | return -EOPNOTSUPP; | |
2e149670 | 77 | if (!inode_owner_or_capable(inode)) |
f0c8bd16 AG |
78 | return -EPERM; |
79 | if (value) { | |
80 | acl = posix_acl_from_xattr(value, size); | |
81 | if (IS_ERR(acl)) | |
82 | return PTR_ERR(acl); | |
83 | } | |
84 | if (acl) { | |
85 | mode_t mode; | |
86 | ||
87 | error = posix_acl_valid(acl); | |
88 | if (error) | |
89 | goto failed; | |
1c7c474c CH |
90 | switch (type) { |
91 | case ACL_TYPE_ACCESS: | |
92 | mode = inode->i_mode; | |
93 | error = posix_acl_equiv_mode(acl, &mode); | |
94 | if (error < 0) | |
95 | goto failed; | |
96 | inode->i_mode = mode; | |
dad5eb6d | 97 | inode->i_ctime = CURRENT_TIME; |
1c7c474c CH |
98 | if (error == 0) { |
99 | posix_acl_release(acl); | |
100 | acl = NULL; | |
101 | } | |
102 | break; | |
103 | case ACL_TYPE_DEFAULT: | |
104 | if (!S_ISDIR(inode->i_mode)) { | |
105 | error = -EINVAL; | |
106 | goto failed; | |
107 | } | |
108 | break; | |
f0c8bd16 AG |
109 | } |
110 | } | |
1c7c474c | 111 | set_cached_acl(inode, type, acl); |
f0c8bd16 AG |
112 | error = 0; |
113 | failed: | |
114 | posix_acl_release(acl); | |
115 | return error; | |
116 | } | |
117 | ||
118 | /** | |
119 | * generic_acl_init - Take care of acl inheritance at @inode create time | |
f0c8bd16 AG |
120 | * |
121 | * Files created inside a directory with a default ACL inherit the | |
122 | * directory's default ACL. | |
123 | */ | |
124 | int | |
1c7c474c | 125 | generic_acl_init(struct inode *inode, struct inode *dir) |
f0c8bd16 AG |
126 | { |
127 | struct posix_acl *acl = NULL; | |
f0c8bd16 AG |
128 | int error; |
129 | ||
f0c8bd16 | 130 | if (!S_ISLNK(inode->i_mode)) |
1c7c474c | 131 | acl = get_cached_acl(dir, ACL_TYPE_DEFAULT); |
f0c8bd16 | 132 | if (acl) { |
95203bef AV |
133 | if (S_ISDIR(inode->i_mode)) |
134 | set_cached_acl(inode, ACL_TYPE_DEFAULT, acl); | |
d3fb6120 | 135 | error = posix_acl_create(&acl, GFP_KERNEL, &inode->i_mode); |
826cae2f AV |
136 | if (error < 0) |
137 | return error; | |
826cae2f AV |
138 | if (error > 0) |
139 | set_cached_acl(inode, ACL_TYPE_ACCESS, acl); | |
d3fb6120 AV |
140 | } else { |
141 | inode->i_mode &= ~current_umask(); | |
f0c8bd16 AG |
142 | } |
143 | error = 0; | |
144 | ||
f0c8bd16 AG |
145 | posix_acl_release(acl); |
146 | return error; | |
147 | } | |
148 | ||
149 | /** | |
150 | * generic_acl_chmod - change the access acl of @inode upon chmod() | |
f0c8bd16 AG |
151 | * |
152 | * A chmod also changes the permissions of the owner, group/mask, and | |
153 | * other ACL entries. | |
154 | */ | |
155 | int | |
1c7c474c | 156 | generic_acl_chmod(struct inode *inode) |
f0c8bd16 | 157 | { |
bc26ab5f | 158 | struct posix_acl *acl; |
f0c8bd16 AG |
159 | int error = 0; |
160 | ||
161 | if (S_ISLNK(inode->i_mode)) | |
162 | return -EOPNOTSUPP; | |
1c7c474c | 163 | acl = get_cached_acl(inode, ACL_TYPE_ACCESS); |
f0c8bd16 | 164 | if (acl) { |
bc26ab5f AV |
165 | error = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode); |
166 | if (error) | |
167 | return error; | |
168 | set_cached_acl(inode, ACL_TYPE_ACCESS, acl); | |
f0c8bd16 | 169 | posix_acl_release(acl); |
f0c8bd16 AG |
170 | } |
171 | return error; | |
172 | } | |
1c7c474c | 173 | |
bb435453 | 174 | const struct xattr_handler generic_acl_access_handler = { |
1c7c474c CH |
175 | .prefix = POSIX_ACL_XATTR_ACCESS, |
176 | .flags = ACL_TYPE_ACCESS, | |
177 | .list = generic_acl_list, | |
178 | .get = generic_acl_get, | |
179 | .set = generic_acl_set, | |
180 | }; | |
181 | ||
bb435453 | 182 | const struct xattr_handler generic_acl_default_handler = { |
1c7c474c CH |
183 | .prefix = POSIX_ACL_XATTR_DEFAULT, |
184 | .flags = ACL_TYPE_DEFAULT, | |
185 | .list = generic_acl_list, | |
186 | .get = generic_acl_get, | |
187 | .set = generic_acl_set, | |
188 | }; |