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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_format.h"
21#include "xfs_log_format.h"
22#include "xfs_trans_resv.h"
23#include "xfs_sb.h"
24#include "xfs_ag.h"
25#include "xfs_mount.h"
26#include "xfs_da_format.h"
27#include "xfs_inode.h"
28#include "xfs_attr.h"
29#include "xfs_attr_leaf.h"
30#include "xfs_acl.h"
31
32#include <linux/posix_acl_xattr.h>
33#include <linux/xattr.h>
34
35
36static int
37xfs_xattr_get(struct dentry *dentry, const char *name,
38 void *value, size_t size, int xflags)
39{
40 struct xfs_inode *ip = XFS_I(dentry->d_inode);
41 int error, asize = size;
42
43 if (strcmp(name, "") == 0)
44 return -EINVAL;
45
46 /* Convert Linux syscall to XFS internal ATTR flags */
47 if (!size) {
48 xflags |= ATTR_KERNOVAL;
49 value = NULL;
50 }
51
52 error = -xfs_attr_get(ip, (unsigned char *)name, value, &asize, xflags);
53 if (error)
54 return error;
55 return asize;
56}
57
58static int
59xfs_xattr_set(struct dentry *dentry, const char *name, const void *value,
60 size_t size, int flags, int xflags)
61{
62 struct xfs_inode *ip = XFS_I(dentry->d_inode);
63
64 if (strcmp(name, "") == 0)
65 return -EINVAL;
66
67 /* Convert Linux syscall to XFS internal ATTR flags */
68 if (flags & XATTR_CREATE)
69 xflags |= ATTR_CREATE;
70 if (flags & XATTR_REPLACE)
71 xflags |= ATTR_REPLACE;
72
73 if (!value)
74 return -xfs_attr_remove(ip, (unsigned char *)name, xflags);
75 return -xfs_attr_set(ip, (unsigned char *)name,
76 (void *)value, size, xflags);
77}
78
79static const struct xattr_handler xfs_xattr_user_handler = {
80 .prefix = XATTR_USER_PREFIX,
81 .flags = 0, /* no flags implies user namespace */
82 .get = xfs_xattr_get,
83 .set = xfs_xattr_set,
84};
85
86static const struct xattr_handler xfs_xattr_trusted_handler = {
87 .prefix = XATTR_TRUSTED_PREFIX,
88 .flags = ATTR_ROOT,
89 .get = xfs_xattr_get,
90 .set = xfs_xattr_set,
91};
92
93static const struct xattr_handler xfs_xattr_security_handler = {
94 .prefix = XATTR_SECURITY_PREFIX,
95 .flags = ATTR_SECURE,
96 .get = xfs_xattr_get,
97 .set = xfs_xattr_set,
98};
99
100const struct xattr_handler *xfs_xattr_handlers[] = {
101 &xfs_xattr_user_handler,
102 &xfs_xattr_trusted_handler,
103 &xfs_xattr_security_handler,
104#ifdef CONFIG_XFS_POSIX_ACL
105 &posix_acl_access_xattr_handler,
106 &posix_acl_default_xattr_handler,
107#endif
108 NULL
109};
110
111static unsigned int xfs_xattr_prefix_len(int flags)
112{
113 if (flags & XFS_ATTR_SECURE)
114 return sizeof("security");
115 else if (flags & XFS_ATTR_ROOT)
116 return sizeof("trusted");
117 else
118 return sizeof("user");
119}
120
121static const char *xfs_xattr_prefix(int flags)
122{
123 if (flags & XFS_ATTR_SECURE)
124 return xfs_xattr_security_handler.prefix;
125 else if (flags & XFS_ATTR_ROOT)
126 return xfs_xattr_trusted_handler.prefix;
127 else
128 return xfs_xattr_user_handler.prefix;
129}
130
131static int
132xfs_xattr_put_listent(
133 struct xfs_attr_list_context *context,
134 int flags,
135 unsigned char *name,
136 int namelen,
137 int valuelen,
138 unsigned char *value)
139{
140 unsigned int prefix_len = xfs_xattr_prefix_len(flags);
141 char *offset;
142 int arraytop;
143
144 ASSERT(context->count >= 0);
145
146 /*
147 * Only show root namespace entries if we are actually allowed to
148 * see them.
149 */
150 if ((flags & XFS_ATTR_ROOT) && !capable(CAP_SYS_ADMIN))
151 return 0;
152
153 arraytop = context->count + prefix_len + namelen + 1;
154 if (arraytop > context->firstu) {
155 context->count = -1; /* insufficient space */
156 return 1;
157 }
158 offset = (char *)context->alist + context->count;
159 strncpy(offset, xfs_xattr_prefix(flags), prefix_len);
160 offset += prefix_len;
161 strncpy(offset, (char *)name, namelen); /* real name */
162 offset += namelen;
163 *offset = '\0';
164 context->count += prefix_len + namelen + 1;
165 return 0;
166}
167
168static int
169xfs_xattr_put_listent_sizes(
170 struct xfs_attr_list_context *context,
171 int flags,
172 unsigned char *name,
173 int namelen,
174 int valuelen,
175 unsigned char *value)
176{
177 context->count += xfs_xattr_prefix_len(flags) + namelen + 1;
178 return 0;
179}
180
181static int
182list_one_attr(const char *name, const size_t len, void *data,
183 size_t size, ssize_t *result)
184{
185 char *p = data + *result;
186
187 *result += len;
188 if (!size)
189 return 0;
190 if (*result > size)
191 return -ERANGE;
192
193 strcpy(p, name);
194 return 0;
195}
196
197ssize_t
198xfs_vn_listxattr(struct dentry *dentry, char *data, size_t size)
199{
200 struct xfs_attr_list_context context;
201 struct attrlist_cursor_kern cursor = { 0 };
202 struct inode *inode = dentry->d_inode;
203 int error;
204
205 /*
206 * First read the regular on-disk attributes.
207 */
208 memset(&context, 0, sizeof(context));
209 context.dp = XFS_I(inode);
210 context.cursor = &cursor;
211 context.resynch = 1;
212 context.alist = data;
213 context.bufsize = size;
214 context.firstu = context.bufsize;
215
216 if (size)
217 context.put_listent = xfs_xattr_put_listent;
218 else
219 context.put_listent = xfs_xattr_put_listent_sizes;
220
221 xfs_attr_list_int(&context);
222 if (context.count < 0)
223 return -ERANGE;
224
225 /*
226 * Then add the two synthetic ACL attributes.
227 */
228 if (posix_acl_access_exists(inode)) {
229 error = list_one_attr(POSIX_ACL_XATTR_ACCESS,
230 strlen(POSIX_ACL_XATTR_ACCESS) + 1,
231 data, size, &context.count);
232 if (error)
233 return error;
234 }
235
236 if (posix_acl_default_exists(inode)) {
237 error = list_one_attr(POSIX_ACL_XATTR_DEFAULT,
238 strlen(POSIX_ACL_XATTR_DEFAULT) + 1,
239 data, size, &context.count);
240 if (error)
241 return error;
242 }
243
244 return context.count;
245}
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_format.h"
21#include "xfs_log_format.h"
22#include "xfs_trans_resv.h"
23#include "xfs_mount.h"
24#include "xfs_da_format.h"
25#include "xfs_inode.h"
26#include "xfs_attr.h"
27#include "xfs_attr_leaf.h"
28#include "xfs_acl.h"
29
30#include <linux/posix_acl_xattr.h>
31#include <linux/xattr.h>
32
33
34static int
35xfs_xattr_get(const struct xattr_handler *handler, struct dentry *dentry,
36 const char *name, void *value, size_t size)
37{
38 int xflags = handler->flags;
39 struct xfs_inode *ip = XFS_I(d_inode(dentry));
40 int error, asize = size;
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
54void
55xfs_forget_acl(
56 struct inode *inode,
57 const char *name,
58 int xflags)
59{
60 /*
61 * Invalidate any cached ACLs if the user has bypassed the ACL
62 * interface. We don't validate the content whatsoever so it is caller
63 * responsibility to provide data in valid format and ensure i_mode is
64 * consistent.
65 */
66 if (xflags & ATTR_ROOT) {
67#ifdef CONFIG_XFS_POSIX_ACL
68 if (!strcmp(name, SGI_ACL_FILE))
69 forget_cached_acl(inode, ACL_TYPE_ACCESS);
70 else if (!strcmp(name, SGI_ACL_DEFAULT))
71 forget_cached_acl(inode, ACL_TYPE_DEFAULT);
72#endif
73 }
74}
75
76static int
77xfs_xattr_set(const struct xattr_handler *handler, struct dentry *dentry,
78 const char *name, const void *value, size_t size, int flags)
79{
80 int xflags = handler->flags;
81 struct xfs_inode *ip = XFS_I(d_inode(dentry));
82 int error;
83
84 /* Convert Linux syscall to XFS internal ATTR flags */
85 if (flags & XATTR_CREATE)
86 xflags |= ATTR_CREATE;
87 if (flags & XATTR_REPLACE)
88 xflags |= ATTR_REPLACE;
89
90 if (!value)
91 return xfs_attr_remove(ip, (unsigned char *)name, xflags);
92 error = xfs_attr_set(ip, (unsigned char *)name,
93 (void *)value, size, xflags);
94 if (!error)
95 xfs_forget_acl(d_inode(dentry), name, xflags);
96
97 return error;
98}
99
100static const struct xattr_handler xfs_xattr_user_handler = {
101 .prefix = XATTR_USER_PREFIX,
102 .flags = 0, /* no flags implies user namespace */
103 .get = xfs_xattr_get,
104 .set = xfs_xattr_set,
105};
106
107static const struct xattr_handler xfs_xattr_trusted_handler = {
108 .prefix = XATTR_TRUSTED_PREFIX,
109 .flags = ATTR_ROOT,
110 .get = xfs_xattr_get,
111 .set = xfs_xattr_set,
112};
113
114static const struct xattr_handler xfs_xattr_security_handler = {
115 .prefix = XATTR_SECURITY_PREFIX,
116 .flags = ATTR_SECURE,
117 .get = xfs_xattr_get,
118 .set = xfs_xattr_set,
119};
120
121const struct xattr_handler *xfs_xattr_handlers[] = {
122 &xfs_xattr_user_handler,
123 &xfs_xattr_trusted_handler,
124 &xfs_xattr_security_handler,
125#ifdef CONFIG_XFS_POSIX_ACL
126 &posix_acl_access_xattr_handler,
127 &posix_acl_default_xattr_handler,
128#endif
129 NULL
130};
131
132static int
133__xfs_xattr_put_listent(
134 struct xfs_attr_list_context *context,
135 char *prefix,
136 int prefix_len,
137 unsigned char *name,
138 int namelen)
139{
140 char *offset;
141 int arraytop;
142
143 if (!context->alist)
144 goto compute_size;
145
146 arraytop = context->count + prefix_len + namelen + 1;
147 if (arraytop > context->firstu) {
148 context->count = -1; /* insufficient space */
149 return 1;
150 }
151 offset = (char *)context->alist + context->count;
152 strncpy(offset, prefix, prefix_len);
153 offset += prefix_len;
154 strncpy(offset, (char *)name, namelen); /* real name */
155 offset += namelen;
156 *offset = '\0';
157
158compute_size:
159 context->count += prefix_len + namelen + 1;
160 return 0;
161}
162
163static int
164xfs_xattr_put_listent(
165 struct xfs_attr_list_context *context,
166 int flags,
167 unsigned char *name,
168 int namelen,
169 int valuelen,
170 unsigned char *value)
171{
172 char *prefix;
173 int prefix_len;
174
175 ASSERT(context->count >= 0);
176
177 if (flags & XFS_ATTR_ROOT) {
178#ifdef CONFIG_XFS_POSIX_ACL
179 if (namelen == SGI_ACL_FILE_SIZE &&
180 strncmp(name, SGI_ACL_FILE,
181 SGI_ACL_FILE_SIZE) == 0) {
182 int ret = __xfs_xattr_put_listent(
183 context, XATTR_SYSTEM_PREFIX,
184 XATTR_SYSTEM_PREFIX_LEN,
185 XATTR_POSIX_ACL_ACCESS,
186 strlen(XATTR_POSIX_ACL_ACCESS));
187 if (ret)
188 return ret;
189 } else if (namelen == SGI_ACL_DEFAULT_SIZE &&
190 strncmp(name, SGI_ACL_DEFAULT,
191 SGI_ACL_DEFAULT_SIZE) == 0) {
192 int ret = __xfs_xattr_put_listent(
193 context, XATTR_SYSTEM_PREFIX,
194 XATTR_SYSTEM_PREFIX_LEN,
195 XATTR_POSIX_ACL_DEFAULT,
196 strlen(XATTR_POSIX_ACL_DEFAULT));
197 if (ret)
198 return ret;
199 }
200#endif
201
202 /*
203 * Only show root namespace entries if we are actually allowed to
204 * see them.
205 */
206 if (!capable(CAP_SYS_ADMIN))
207 return 0;
208
209 prefix = XATTR_TRUSTED_PREFIX;
210 prefix_len = XATTR_TRUSTED_PREFIX_LEN;
211 } else if (flags & XFS_ATTR_SECURE) {
212 prefix = XATTR_SECURITY_PREFIX;
213 prefix_len = XATTR_SECURITY_PREFIX_LEN;
214 } else {
215 prefix = XATTR_USER_PREFIX;
216 prefix_len = XATTR_USER_PREFIX_LEN;
217 }
218
219 return __xfs_xattr_put_listent(context, prefix, prefix_len, name,
220 namelen);
221}
222
223ssize_t
224xfs_vn_listxattr(struct dentry *dentry, char *data, size_t size)
225{
226 struct xfs_attr_list_context context;
227 struct attrlist_cursor_kern cursor = { 0 };
228 struct inode *inode = d_inode(dentry);
229
230 /*
231 * First read the regular on-disk attributes.
232 */
233 memset(&context, 0, sizeof(context));
234 context.dp = XFS_I(inode);
235 context.cursor = &cursor;
236 context.resynch = 1;
237 context.alist = size ? data : NULL;
238 context.bufsize = size;
239 context.firstu = context.bufsize;
240 context.put_listent = xfs_xattr_put_listent;
241
242 xfs_attr_list_int(&context);
243 if (context.count < 0)
244 return -ERANGE;
245
246 return context.count;
247}