LXR linux/drivers/staging/lustre/lustre/llite/xattr

   1/*
   2 * GPL HEADER START
   3 *
   4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 only,
   8 * as published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful, but
  11 * WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 * General Public License version 2 for more details (a copy is included
  14 * in the LICENSE file that accompanied this code).
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * version 2 along with this program; If not, see http://www.gnu.org/licenses
  18 *
  19 * GPL HEADER END
  20 */
  21
  22/*
  23 * Copyright (c) 2014 Bull SAS
  24 * Author: Sebastien Buisson sebastien.buisson@bull.net
  25 */
  26
  27/*
  28 * lustre/llite/xattr_security.c
  29 * Handler for storing security labels as extended attributes.
  30 */
  31#include <linux/security.h>
  32#include <linux/xattr.h>
  33#include "llite_internal.h"
  34
  35/**
  36 * A helper function for ll_security_inode_init_security()
  37 * that takes care of setting xattrs
  38 *
  39 * Get security context of @inode from @xattr_array,
  40 * and put it in 'security.xxx' xattr of dentry
  41 * stored in @fs_info.
  42 *
  43 * \retval 0        success
  44 * \retval -ENOMEM  if no memory could be allocated for xattr name
  45 * \retval < 0      failure to set xattr
  46 */
  47static int
  48ll_initxattrs(struct inode *inode, const struct xattr *xattr_array,
  49              void *fs_info)
  50{
  51        const struct xattr_handler *handler;
  52        struct dentry *dentry = fs_info;
  53        const struct xattr *xattr;
  54        int err = 0;
  55
  56        handler = get_xattr_type(XATTR_SECURITY_PREFIX);
  57        if (!handler)
  58                return -ENXIO;
  59
  60        for (xattr = xattr_array; xattr->name; xattr++) {
  61                err = handler->set(handler, dentry, inode, xattr->name,
  62                                   xattr->value, xattr->value_len,
  63                                   XATTR_CREATE);
  64                if (err < 0)
  65                        break;
  66        }
  67        return err;
  68}
  69
  70/**
  71 * Initializes security context
  72 *
  73 * Get security context of @inode in @dir,
  74 * and put it in 'security.xxx' xattr of @dentry.
  75 *
  76 * \retval 0        success, or SELinux is disabled
  77 * \retval -ENOMEM  if no memory could be allocated for xattr name
  78 * \retval < 0      failure to get security context or set xattr
  79 */
  80int
  81ll_init_security(struct dentry *dentry, struct inode *inode, struct inode *dir)
  82{
  83        if (!selinux_is_enabled())
  84                return 0;
  85
  86        return security_inode_init_security(inode, dir, NULL,
  87                                            &ll_initxattrs, dentry);
  88}
  89