diff options
Diffstat (limited to 'fs/xfs/xfs_xattr.c')
-rw-r--r-- | fs/xfs/xfs_xattr.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c new file mode 100644 index 000000000000..87d3e03878c8 --- /dev/null +++ b/fs/xfs/xfs_xattr.c | |||
@@ -0,0 +1,241 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2008 Christoph Hellwig. | ||
3 | * Portions Copyright (C) 2000-2008 Silicon Graphics, Inc. | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or | ||
6 | * modify it under the terms of the GNU General Public License as | ||
7 | * published by the Free Software Foundation. | ||
8 | * | ||
9 | * This program is distributed in the hope that it would be useful, | ||
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
12 | * GNU General Public License for more details. | ||
13 | * | ||
14 | * You should have received a copy of the GNU General Public License | ||
15 | * along with this program; if not, write the Free Software Foundation, | ||
16 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | ||
17 | */ | ||
18 | |||
19 | #include "xfs.h" | ||
20 | #include "xfs_da_btree.h" | ||
21 | #include "xfs_bmap_btree.h" | ||
22 | #include "xfs_inode.h" | ||
23 | #include "xfs_attr.h" | ||
24 | #include "xfs_attr_leaf.h" | ||
25 | #include "xfs_acl.h" | ||
26 | #include "xfs_vnodeops.h" | ||
27 | |||
28 | #include <linux/posix_acl_xattr.h> | ||
29 | #include <linux/xattr.h> | ||
30 | |||
31 | |||
32 | static int | ||
33 | xfs_xattr_get(struct dentry *dentry, const char *name, | ||
34 | void *value, size_t size, int xflags) | ||
35 | { | ||
36 | struct xfs_inode *ip = XFS_I(dentry->d_inode); | ||
37 | int error, asize = size; | ||
38 | |||
39 | if (strcmp(name, "") == 0) | ||
40 | return -EINVAL; | ||
41 | |||
42 | /* Convert Linux syscall to XFS internal ATTR flags */ | ||
43 | if (!size) { | ||
44 | xflags |= ATTR_KERNOVAL; | ||
45 | value = NULL; | ||
46 | } | ||
47 | |||
48 | error = -xfs_attr_get(ip, (unsigned char *)name, value, &asize, xflags); | ||
49 | if (error) | ||
50 | return error; | ||
51 | return asize; | ||
52 | } | ||
53 | |||
54 | static int | ||
55 | xfs_xattr_set(struct dentry *dentry, const char *name, const void *value, | ||
56 | size_t size, int flags, int xflags) | ||
57 | { | ||
58 | struct xfs_inode *ip = XFS_I(dentry->d_inode); | ||
59 | |||
60 | if (strcmp(name, "") == 0) | ||
61 | return -EINVAL; | ||
62 | |||
63 | /* Convert Linux syscall to XFS internal ATTR flags */ | ||
64 | if (flags & XATTR_CREATE) | ||
65 | xflags |= ATTR_CREATE; | ||
66 | if (flags & XATTR_REPLACE) | ||
67 | xflags |= ATTR_REPLACE; | ||
68 | |||
69 | if (!value) | ||
70 | return -xfs_attr_remove(ip, (unsigned char *)name, xflags); | ||
71 | return -xfs_attr_set(ip, (unsigned char *)name, | ||
72 | (void *)value, size, xflags); | ||
73 | } | ||
74 | |||
75 | static const struct xattr_handler xfs_xattr_user_handler = { | ||
76 | .prefix = XATTR_USER_PREFIX, | ||
77 | .flags = 0, /* no flags implies user namespace */ | ||
78 | .get = xfs_xattr_get, | ||
79 | .set = xfs_xattr_set, | ||
80 | }; | ||
81 | |||
82 | static const struct xattr_handler xfs_xattr_trusted_handler = { | ||
83 | .prefix = XATTR_TRUSTED_PREFIX, | ||
84 | .flags = ATTR_ROOT, | ||
85 | .get = xfs_xattr_get, | ||
86 | .set = xfs_xattr_set, | ||
87 | }; | ||
88 | |||
89 | static const struct xattr_handler xfs_xattr_security_handler = { | ||
90 | .prefix = XATTR_SECURITY_PREFIX, | ||
91 | .flags = ATTR_SECURE, | ||
92 | .get = xfs_xattr_get, | ||
93 | .set = xfs_xattr_set, | ||
94 | }; | ||
95 | |||
96 | const struct xattr_handler *xfs_xattr_handlers[] = { | ||
97 | &xfs_xattr_user_handler, | ||
98 | &xfs_xattr_trusted_handler, | ||
99 | &xfs_xattr_security_handler, | ||
100 | #ifdef CONFIG_XFS_POSIX_ACL | ||
101 | &xfs_xattr_acl_access_handler, | ||
102 | &xfs_xattr_acl_default_handler, | ||
103 | #endif | ||
104 | NULL | ||
105 | }; | ||
106 | |||
107 | static unsigned int xfs_xattr_prefix_len(int flags) | ||
108 | { | ||
109 | if (flags & XFS_ATTR_SECURE) | ||
110 | return sizeof("security"); | ||
111 | else if (flags & XFS_ATTR_ROOT) | ||
112 | return sizeof("trusted"); | ||
113 | else | ||
114 | return sizeof("user"); | ||
115 | } | ||
116 | |||
117 | static const char *xfs_xattr_prefix(int flags) | ||
118 | { | ||
119 | if (flags & XFS_ATTR_SECURE) | ||
120 | return xfs_xattr_security_handler.prefix; | ||
121 | else if (flags & XFS_ATTR_ROOT) | ||
122 | return xfs_xattr_trusted_handler.prefix; | ||
123 | else | ||
124 | return xfs_xattr_user_handler.prefix; | ||
125 | } | ||
126 | |||
127 | static int | ||
128 | xfs_xattr_put_listent( | ||
129 | struct xfs_attr_list_context *context, | ||
130 | int flags, | ||
131 | unsigned char *name, | ||
132 | int namelen, | ||
133 | int valuelen, | ||
134 | unsigned char *value) | ||
135 | { | ||
136 | unsigned int prefix_len = xfs_xattr_prefix_len(flags); | ||
137 | char *offset; | ||
138 | int arraytop; | ||
139 | |||
140 | ASSERT(context->count >= 0); | ||
141 | |||
142 | /* | ||
143 | * Only show root namespace entries if we are actually allowed to | ||
144 | * see them. | ||
145 | */ | ||
146 | if ((flags & XFS_ATTR_ROOT) && !capable(CAP_SYS_ADMIN)) | ||
147 | return 0; | ||
148 | |||
149 | arraytop = context->count + prefix_len + namelen + 1; | ||
150 | if (arraytop > context->firstu) { | ||
151 | context->count = -1; /* insufficient space */ | ||
152 | return 1; | ||
153 | } | ||
154 | offset = (char *)context->alist + context->count; | ||
155 | strncpy(offset, xfs_xattr_prefix(flags), prefix_len); | ||
156 | offset += prefix_len; | ||
157 | strncpy(offset, (char *)name, namelen); /* real name */ | ||
158 | offset += namelen; | ||
159 | *offset = '\0'; | ||
160 | context->count += prefix_len + namelen + 1; | ||
161 | return 0; | ||
162 | } | ||
163 | |||
164 | static int | ||
165 | xfs_xattr_put_listent_sizes( | ||
166 | struct xfs_attr_list_context *context, | ||
167 | int flags, | ||
168 | unsigned char *name, | ||
169 | int namelen, | ||
170 | int valuelen, | ||
171 | unsigned char *value) | ||
172 | { | ||
173 | context->count += xfs_xattr_prefix_len(flags) + namelen + 1; | ||
174 | return 0; | ||
175 | } | ||
176 | |||
177 | static int | ||
178 | list_one_attr(const char *name, const size_t len, void *data, | ||
179 | size_t size, ssize_t *result) | ||
180 | { | ||
181 | char *p = data + *result; | ||
182 | |||
183 | *result += len; | ||
184 | if (!size) | ||
185 | return 0; | ||
186 | if (*result > size) | ||
187 | return -ERANGE; | ||
188 | |||
189 | strcpy(p, name); | ||
190 | return 0; | ||
191 | } | ||
192 | |||
193 | ssize_t | ||
194 | xfs_vn_listxattr(struct dentry *dentry, char *data, size_t size) | ||
195 | { | ||
196 | struct xfs_attr_list_context context; | ||
197 | struct attrlist_cursor_kern cursor = { 0 }; | ||
198 | struct inode *inode = dentry->d_inode; | ||
199 | int error; | ||
200 | |||
201 | /* | ||
202 | * First read the regular on-disk attributes. | ||
203 | */ | ||
204 | memset(&context, 0, sizeof(context)); | ||
205 | context.dp = XFS_I(inode); | ||
206 | context.cursor = &cursor; | ||
207 | context.resynch = 1; | ||
208 | context.alist = data; | ||
209 | context.bufsize = size; | ||
210 | context.firstu = context.bufsize; | ||
211 | |||
212 | if (size) | ||
213 | context.put_listent = xfs_xattr_put_listent; | ||
214 | else | ||
215 | context.put_listent = xfs_xattr_put_listent_sizes; | ||
216 | |||
217 | xfs_attr_list_int(&context); | ||
218 | if (context.count < 0) | ||
219 | return -ERANGE; | ||
220 | |||
221 | /* | ||
222 | * Then add the two synthetic ACL attributes. | ||
223 | */ | ||
224 | if (posix_acl_access_exists(inode)) { | ||
225 | error = list_one_attr(POSIX_ACL_XATTR_ACCESS, | ||
226 | strlen(POSIX_ACL_XATTR_ACCESS) + 1, | ||
227 | data, size, &context.count); | ||
228 | if (error) | ||
229 | return error; | ||
230 | } | ||
231 | |||
232 | if (posix_acl_default_exists(inode)) { | ||
233 | error = list_one_attr(POSIX_ACL_XATTR_DEFAULT, | ||
234 | strlen(POSIX_ACL_XATTR_DEFAULT) + 1, | ||
235 | data, size, &context.count); | ||
236 | if (error) | ||
237 | return error; | ||
238 | } | ||
239 | |||
240 | return context.count; | ||
241 | } | ||