2 * Copyright (C) 2008 Christoph Hellwig.
3 * Portions Copyright (C) 2000-2008 Silicon Graphics, Inc.
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.
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.
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
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"
27 #include "xfs_attr_leaf.h"
30 #include <linux/posix_acl_xattr.h>
31 #include <linux/xattr.h>
35 xfs_xattr_get(const struct xattr_handler *handler, struct dentry *dentry,
36 const char *name, void *value, size_t size)
38 int xflags = handler->flags;
39 struct xfs_inode *ip = XFS_I(d_inode(dentry));
40 int error, asize = size;
42 /* Convert Linux syscall to XFS internal ATTR flags */
44 xflags |= ATTR_KERNOVAL;
48 error = xfs_attr_get(ip, (unsigned char *)name, value, &asize, xflags);
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
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);
77 xfs_xattr_set(const struct xattr_handler *handler, struct dentry *dentry,
78 const char *name, const void *value, size_t size, int flags)
80 int xflags = handler->flags;
81 struct xfs_inode *ip = XFS_I(d_inode(dentry));
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;
91 return xfs_attr_remove(ip, (unsigned char *)name, xflags);
92 error = xfs_attr_set(ip, (unsigned char *)name,
93 (void *)value, size, xflags);
95 xfs_forget_acl(d_inode(dentry), name, xflags);
100 static 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,
107 static const struct xattr_handler xfs_xattr_trusted_handler = {
108 .prefix = XATTR_TRUSTED_PREFIX,
110 .get = xfs_xattr_get,
111 .set = xfs_xattr_set,
114 static 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,
121 const 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,
132 static unsigned int xfs_xattr_prefix_len(int flags)
134 if (flags & XFS_ATTR_SECURE)
135 return sizeof("security");
136 else if (flags & XFS_ATTR_ROOT)
137 return sizeof("trusted");
139 return sizeof("user");
142 static const char *xfs_xattr_prefix(int flags)
144 if (flags & XFS_ATTR_SECURE)
145 return xfs_xattr_security_handler.prefix;
146 else if (flags & XFS_ATTR_ROOT)
147 return xfs_xattr_trusted_handler.prefix;
149 return xfs_xattr_user_handler.prefix;
153 xfs_xattr_put_listent(
154 struct xfs_attr_list_context *context,
159 unsigned char *value)
161 unsigned int prefix_len = xfs_xattr_prefix_len(flags);
165 ASSERT(context->count >= 0);
168 * Only show root namespace entries if we are actually allowed to
171 if ((flags & XFS_ATTR_ROOT) && !capable(CAP_SYS_ADMIN))
174 arraytop = context->count + prefix_len + namelen + 1;
175 if (arraytop > context->firstu) {
176 context->count = -1; /* insufficient space */
179 offset = (char *)context->alist + context->count;
180 strncpy(offset, xfs_xattr_prefix(flags), prefix_len);
181 offset += prefix_len;
182 strncpy(offset, (char *)name, namelen); /* real name */
185 context->count += prefix_len + namelen + 1;
190 xfs_xattr_put_listent_sizes(
191 struct xfs_attr_list_context *context,
196 unsigned char *value)
198 context->count += xfs_xattr_prefix_len(flags) + namelen + 1;
203 list_one_attr(const char *name, const size_t len, void *data,
204 size_t size, ssize_t *result)
206 char *p = data + *result;
219 xfs_vn_listxattr(struct dentry *dentry, char *data, size_t size)
221 struct xfs_attr_list_context context;
222 struct attrlist_cursor_kern cursor = { 0 };
223 struct inode *inode = d_inode(dentry);
227 * First read the regular on-disk attributes.
229 memset(&context, 0, sizeof(context));
230 context.dp = XFS_I(inode);
231 context.cursor = &cursor;
233 context.alist = data;
234 context.bufsize = size;
235 context.firstu = context.bufsize;
238 context.put_listent = xfs_xattr_put_listent;
240 context.put_listent = xfs_xattr_put_listent_sizes;
242 xfs_attr_list_int(&context);
243 if (context.count < 0)
247 * Then add the two synthetic ACL attributes.
249 if (posix_acl_access_exists(inode)) {
250 error = list_one_attr(XATTR_NAME_POSIX_ACL_ACCESS,
251 strlen(XATTR_NAME_POSIX_ACL_ACCESS) + 1,
252 data, size, &context.count);
257 if (posix_acl_default_exists(inode)) {
258 error = list_one_attr(XATTR_NAME_POSIX_ACL_DEFAULT,
259 strlen(XATTR_NAME_POSIX_ACL_DEFAULT) + 1,
260 data, size, &context.count);
265 return context.count;