LXR linux/security/apparmor/lib.c

   1/*
   2 * AppArmor security module
   3 *
   4 * This file contains basic common functions used in AppArmor
   5 *
   6 * Copyright (C) 1998-2008 Novell/SUSE
   7 * Copyright 2009-2010 Canonical Ltd.
   8 *
   9 * This program is free software; you can redistribute it and/or
  10 * modify it under the terms of the GNU General Public License as
  11 * published by the Free Software Foundation, version 2 of the
  12 * License.
  13 */
  14
  15#include <linux/mm.h>
  16#include <linux/slab.h>
  17#include <linux/string.h>
  18#include <linux/vmalloc.h>
  19
  20#include "include/audit.h"
  21#include "include/apparmor.h"
  22
  23
  24/**
  25 * aa_split_fqname - split a fqname into a profile and namespace name
  26 * @fqname: a full qualified name in namespace profile format (NOT NULL)
  27 * @ns_name: pointer to portion of the string containing the ns name (NOT NULL)
  28 *
  29 * Returns: profile name or NULL if one is not specified
  30 *
  31 * Split a namespace name from a profile name (see policy.c for naming
  32 * description).  If a portion of the name is missing it returns NULL for
  33 * that portion.
  34 *
  35 * NOTE: may modify the @fqname string.  The pointers returned point
  36 *       into the @fqname string.
  37 */
  38char *aa_split_fqname(char *fqname, char **ns_name)
  39{
  40        char *name = strim(fqname);
  41
  42        *ns_name = NULL;
  43        if (name[0] == ':') {
  44                char *split = strchr(&name[1], ':');
  45                *ns_name = skip_spaces(&name[1]);
  46                if (split) {
  47                        /* overwrite ':' with \0 */
  48                        *split++ = 0;
  49                        if (strncmp(split, "//", 2) == 0)
  50                                split += 2;
  51                        name = skip_spaces(split);
  52                } else
  53                        /* a ns name without a following profile is allowed */
  54                        name = NULL;
  55        }
  56        if (name && *name == 0)
  57                name = NULL;
  58
  59        return name;
  60}
  61
  62/**
  63 * aa_info_message - log a none profile related status message
  64 * @str: message to log
  65 */
  66void aa_info_message(const char *str)
  67{
  68        if (audit_enabled) {
  69                struct common_audit_data sa;
  70                struct apparmor_audit_data aad = {0,};
  71                sa.type = LSM_AUDIT_DATA_NONE;
  72                sa.aad = &aad;
  73                aad.info = str;
  74                aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, NULL);
  75        }
  76        printk(KERN_INFO "AppArmor: %s\n", str);
  77}
  78
  79/**
  80 * __aa_kvmalloc - do allocation preferring kmalloc but falling back to vmalloc
  81 * @size: how many bytes of memory are required
  82 * @flags: the type of memory to allocate (see kmalloc).
  83 *
  84 * Return: allocated buffer or NULL if failed
  85 *
  86 * It is possible that policy being loaded from the user is larger than
  87 * what can be allocated by kmalloc, in those cases fall back to vmalloc.
  88 */
  89void *__aa_kvmalloc(size_t size, gfp_t flags)
  90{
  91        void *buffer = NULL;
  92
  93        if (size == 0)
  94                return NULL;
  95
  96        /* do not attempt kmalloc if we need more than 16 pages at once */
  97        if (size <= (16*PAGE_SIZE))
  98                buffer = kmalloc(size, flags | GFP_NOIO | __GFP_NOWARN);
  99        if (!buffer) {
 100                if (flags & __GFP_ZERO)
 101                        buffer = vzalloc(size);
 102                else
 103                        buffer = vmalloc(size);
 104        }
 105        return buffer;
 106}
 107