--- /dev/null
+/*
+ * Copyright (C) 2008 Christoph Hellwig.
+ * Portions Copyright (C) 2000-2008 Silicon Graphics, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "xfs.h"
+#include "xfs_da_btree.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_inode.h"
+#include "xfs_attr.h"
+#include "xfs_attr_leaf.h"
+#include "xfs_acl.h"
+#include "xfs_vnodeops.h"
+
+#include <linux/posix_acl_xattr.h>
+#include <linux/xattr.h>
+
+
+/*
+ * ACL handling. Should eventually be moved into xfs_acl.c
+ */
+
+static int
+xfs_decode_acl(const char *name)
+{
+ if (strcmp(name, "posix_acl_access") == 0)
+ return _ACL_TYPE_ACCESS;
+ else if (strcmp(name, "posix_acl_default") == 0)
+ return _ACL_TYPE_DEFAULT;
+ return -EINVAL;
+}
+
+/*
+ * Get system extended attributes which at the moment only
+ * includes Posix ACLs.
+ */
+static int
+xfs_xattr_system_get(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ int acl;
+
+ acl = xfs_decode_acl(name);
+ if (acl < 0)
+ return acl;
+
+ return xfs_acl_vget(inode, buffer, size, acl);
+}
+
+static int
+xfs_xattr_system_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ int error, acl;
+
+ acl = xfs_decode_acl(name);
+ if (acl < 0)
+ return acl;
+ if (flags & XATTR_CREATE)
+ return -EINVAL;
+
+ if (!value)
+ return xfs_acl_vremove(inode, acl);
+
+ error = xfs_acl_vset(inode, (void *)value, size, acl);
+ if (!error)
+ vn_revalidate(inode);
+ return error;
+}
+
+static struct xattr_handler xfs_xattr_system_handler = {
+ .prefix = XATTR_SYSTEM_PREFIX,
+ .get = xfs_xattr_system_get,
+ .set = xfs_xattr_system_set,
+};
+
+
+/*
+ * Real xattr handling. The only difference between the namespaces is
+ * a flag passed to the low-level attr code.
+ */
+
+static int
+__xfs_xattr_get(struct inode *inode, const char *name,
+ void *value, size_t size, int xflags)
+{
+ struct xfs_inode *ip = XFS_I(inode);
+ int error, asize = size;
+
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+
+ /* Convert Linux syscall to XFS internal ATTR flags */
+ if (!size) {
+ xflags |= ATTR_KERNOVAL;
+ value = NULL;
+ }
+
+ error = -xfs_attr_get(ip, name, value, &asize, xflags);
+ if (error)
+ return error;
+ return asize;
+}
+
+static int
+__xfs_xattr_set(struct inode *inode, const char *name, const void *value,
+ size_t size, int flags, int xflags)
+{
+ struct xfs_inode *ip = XFS_I(inode);
+
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+
+ /* Convert Linux syscall to XFS internal ATTR flags */
+ if (flags & XATTR_CREATE)
+ xflags |= ATTR_CREATE;
+ if (flags & XATTR_REPLACE)
+ xflags |= ATTR_REPLACE;
+
+ if (!value)
+ return -xfs_attr_remove(ip, name, xflags);
+ return -xfs_attr_set(ip, name, (void *)value, size, xflags);
+}
+
+static int
+xfs_xattr_user_get(struct inode *inode, const char *name,
+ void *value, size_t size)
+{
+ return __xfs_xattr_get(inode, name, value, size, 0);
+}
+
+static int
+xfs_xattr_user_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ return __xfs_xattr_set(inode, name, value, size, flags, 0);
+}
+
+static struct xattr_handler xfs_xattr_user_handler = {
+ .prefix = XATTR_USER_PREFIX,
+ .get = xfs_xattr_user_get,
+ .set = xfs_xattr_user_set,
+};
+
+
+static int
+xfs_xattr_trusted_get(struct inode *inode, const char *name,
+ void *value, size_t size)
+{
+ return __xfs_xattr_get(inode, name, value, size, ATTR_ROOT);
+}
+
+static int
+xfs_xattr_trusted_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ return __xfs_xattr_set(inode, name, value, size, flags, ATTR_ROOT);
+}
+
+static struct xattr_handler xfs_xattr_trusted_handler = {
+ .prefix = XATTR_TRUSTED_PREFIX,
+ .get = xfs_xattr_trusted_get,
+ .set = xfs_xattr_trusted_set,
+};
+
+
+static int
+xfs_xattr_secure_get(struct inode *inode, const char *name,
+ void *value, size_t size)
+{
+ return __xfs_xattr_get(inode, name, value, size, ATTR_SECURE);
+}
+
+static int
+xfs_xattr_secure_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ return __xfs_xattr_set(inode, name, value, size, flags, ATTR_SECURE);
+}
+
+static struct xattr_handler xfs_xattr_security_handler = {
+ .prefix = XATTR_SECURITY_PREFIX,
+ .get = xfs_xattr_secure_get,
+ .set = xfs_xattr_secure_set,
+};
+
+
+struct xattr_handler *xfs_xattr_handlers[] = {
+ &xfs_xattr_user_handler,
+ &xfs_xattr_trusted_handler,
+ &xfs_xattr_security_handler,
+ &xfs_xattr_system_handler,
+ NULL
+};
+
+static unsigned int xfs_xattr_prefix_len(int flags)
+{
+ if (flags & XFS_ATTR_SECURE)
+ return sizeof("security");
+ else if (flags & XFS_ATTR_ROOT)
+ return sizeof("trusted");
+ else
+ return sizeof("user");
+}
+
+static const char *xfs_xattr_prefix(int flags)
+{
+ if (flags & XFS_ATTR_SECURE)
+ return xfs_xattr_security_handler.prefix;
+ else if (flags & XFS_ATTR_ROOT)
+ return xfs_xattr_trusted_handler.prefix;
+ else
+ return xfs_xattr_user_handler.prefix;
+}
+
+static int
+xfs_xattr_put_listent(struct xfs_attr_list_context *context, int flags,
+ char *name, int namelen, int valuelen, char *value)
+{
+ unsigned int prefix_len = xfs_xattr_prefix_len(flags);
+ char *offset;
+ int arraytop;
+
+ ASSERT(context->count >= 0);
+
+ /*
+ * Only show root namespace entries if we are actually allowed to
+ * see them.
+ */
+ if ((flags & XFS_ATTR_ROOT) && !capable(CAP_SYS_ADMIN))
+ return 0;
+
+ arraytop = context->count + prefix_len + namelen + 1;
+ if (arraytop > context->firstu) {
+ context->count = -1; /* insufficient space */
+ return 1;
+ }
+ offset = (char *)context->alist + context->count;
+ strncpy(offset, xfs_xattr_prefix(flags), prefix_len);
+ offset += prefix_len;
+ strncpy(offset, name, namelen); /* real name */
+ offset += namelen;
+ *offset = '\0';
+ context->count += prefix_len + namelen + 1;
+ return 0;
+}
+
+static int
+xfs_xattr_put_listent_sizes(struct xfs_attr_list_context *context, int flags,
+ char *name, int namelen, int valuelen, char *value)
+{
+ context->count += xfs_xattr_prefix_len(flags) + namelen + 1;
+ return 0;
+}
+
+static int
+list_one_attr(const char *name, const size_t len, void *data,
+ size_t size, ssize_t *result)
+{
+ char *p = data + *result;
+
+ *result += len;
+ if (!size)
+ return 0;
+ if (*result > size)
+ return -ERANGE;
+
+ strcpy(p, name);
+ return 0;
+}
+
+ssize_t
+xfs_vn_listxattr(struct dentry *dentry, char *data, size_t size)
+{
+ struct xfs_attr_list_context context;
+ struct attrlist_cursor_kern cursor = { 0 };
+ struct inode *inode = dentry->d_inode;
+ int error;
+
+ /*
+ * First read the regular on-disk attributes.
+ */
+ memset(&context, 0, sizeof(context));
+ context.dp = XFS_I(inode);
+ context.cursor = &cursor;
+ context.resynch = 1;
+ context.alist = data;
+ context.bufsize = size;
+ context.firstu = context.bufsize;
+
+ if (size)
+ context.put_listent = xfs_xattr_put_listent;
+ else
+ context.put_listent = xfs_xattr_put_listent_sizes;
+
+ xfs_attr_list_int(&context);
+ if (context.count < 0)
+ return -ERANGE;
+
+ /*
+ * Then add the two synthetic ACL attributes.
+ */
+ if (xfs_acl_vhasacl_access(inode)) {
+ error = list_one_attr(POSIX_ACL_XATTR_ACCESS,
+ strlen(POSIX_ACL_XATTR_ACCESS) + 1,
+ data, size, &context.count);
+ if (error)
+ return error;
+ }
+
+ if (xfs_acl_vhasacl_default(inode)) {
+ error = list_one_attr(POSIX_ACL_XATTR_DEFAULT,
+ strlen(POSIX_ACL_XATTR_DEFAULT) + 1,
+ data, size, &context.count);
+ if (error)
+ return error;
+ }
+
+ return context.count;
+}
projects / linux-2.6 / commitdiff