LXR linux/security/tomoyo/path

   1/*
   2 * security/tomoyo/path_group.c
   3 *
   4 * Copyright (C) 2005-2009  NTT DATA CORPORATION
   5 */
   6
   7#include <linux/slab.h>
   8#include "common.h"
   9/* The list for "struct ccs_path_group". */
  10LIST_HEAD(tomoyo_path_group_list);
  11
  12/**
  13 * tomoyo_get_path_group - Allocate memory for "struct tomoyo_path_group".
  14 *
  15 * @group_name: The name of pathname group.
  16 *
  17 * Returns pointer to "struct tomoyo_path_group" on success, NULL otherwise.
  18 */
  19struct tomoyo_path_group *tomoyo_get_path_group(const char *group_name)
  20{
  21        struct tomoyo_path_group *entry = NULL;
  22        struct tomoyo_path_group *group = NULL;
  23        const struct tomoyo_path_info *saved_group_name;
  24        int error = -ENOMEM;
  25        if (!tomoyo_is_correct_path(group_name, 0, 0, 0) ||
  26            !group_name[0])
  27                return NULL;
  28        saved_group_name = tomoyo_get_name(group_name);
  29        if (!saved_group_name)
  30                return NULL;
  31        entry = kzalloc(sizeof(*entry), GFP_NOFS);
  32        if (mutex_lock_interruptible(&tomoyo_policy_lock))
  33                goto out;
  34        list_for_each_entry_rcu(group, &tomoyo_path_group_list, list) {
  35                if (saved_group_name != group->group_name)
  36                        continue;
  37                atomic_inc(&group->users);
  38                error = 0;
  39                break;
  40        }
  41        if (error && tomoyo_memory_ok(entry)) {
  42                INIT_LIST_HEAD(&entry->member_list);
  43                entry->group_name = saved_group_name;
  44                saved_group_name = NULL;
  45                atomic_set(&entry->users, 1);
  46                list_add_tail_rcu(&entry->list, &tomoyo_path_group_list);
  47                group = entry;
  48                entry = NULL;
  49                error = 0;
  50        }
  51        mutex_unlock(&tomoyo_policy_lock);
  52 out:
  53        tomoyo_put_name(saved_group_name);
  54        kfree(entry);
  55        return !error ? group : NULL;
  56}
  57
  58/**
  59 * tomoyo_write_path_group_policy - Write "struct tomoyo_path_group" list.
  60 *
  61 * @data:      String to parse.
  62 * @is_delete: True if it is a delete request.
  63 *
  64 * Returns 0 on success, nagative value otherwise.
  65 */
  66int tomoyo_write_path_group_policy(char *data, const bool is_delete)
  67{
  68        struct tomoyo_path_group *group;
  69        struct tomoyo_path_group_member *member;
  70        struct tomoyo_path_group_member e = { };
  71        int error = is_delete ? -ENOENT : -ENOMEM;
  72        char *w[2];
  73        if (!tomoyo_tokenize(data, w, sizeof(w)) || !w[1][0])
  74                return -EINVAL;
  75        group = tomoyo_get_path_group(w[0]);
  76        if (!group)
  77                return -ENOMEM;
  78        e.member_name = tomoyo_get_name(w[1]);
  79        if (!e.member_name)
  80                goto out;
  81        if (mutex_lock_interruptible(&tomoyo_policy_lock))
  82                goto out;
  83        list_for_each_entry_rcu(member, &group->member_list, list) {
  84                if (member->member_name != e.member_name)
  85                        continue;
  86                member->is_deleted = is_delete;
  87                error = 0;
  88                break;
  89        }
  90        if (!is_delete && error) {
  91                struct tomoyo_path_group_member *entry =
  92                        tomoyo_commit_ok(&e, sizeof(e));
  93                if (entry) {
  94                        list_add_tail_rcu(&entry->list, &group->member_list);
  95                        error = 0;
  96                }
  97        }
  98        mutex_unlock(&tomoyo_policy_lock);
  99 out:
 100        tomoyo_put_name(e.member_name);
 101        tomoyo_put_path_group(group);
 102        return error;
 103}
 104
 105/**
 106 * tomoyo_read_path_group_policy - Read "struct tomoyo_path_group" list.
 107 *
 108 * @head: Pointer to "struct tomoyo_io_buffer".
 109 *
 110 * Returns true on success, false otherwise.
 111 *
 112 * Caller holds tomoyo_read_lock().
 113 */
 114bool tomoyo_read_path_group_policy(struct tomoyo_io_buffer *head)
 115{
 116        struct list_head *gpos;
 117        struct list_head *mpos;
 118        list_for_each_cookie(gpos, head->read_var1, &tomoyo_path_group_list) {
 119                struct tomoyo_path_group *group;
 120                group = list_entry(gpos, struct tomoyo_path_group, list);
 121                list_for_each_cookie(mpos, head->read_var2,
 122                                     &group->member_list) {
 123                        struct tomoyo_path_group_member *member;
 124                        member = list_entry(mpos,
 125                                            struct tomoyo_path_group_member,
 126                                            list);
 127                        if (member->is_deleted)
 128                                continue;
 129                        if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_PATH_GROUP
 130                                              "%s %s\n",
 131                                              group->group_name->name,
 132                                              member->member_name->name))
 133                                return false;
 134                }
 135        }
 136        return true;
 137}
 138
 139/**
 140 * tomoyo_path_matches_group - Check whether the given pathname matches members of the given pathname group.
 141 *
 142 * @pathname:        The name of pathname.
 143 * @group:           Pointer to "struct tomoyo_path_group".
 144 * @may_use_pattern: True if wild card is permitted.
 145 *
 146 * Returns true if @pathname matches pathnames in @group, false otherwise.
 147 *
 148 * Caller holds tomoyo_read_lock().
 149 */
 150bool tomoyo_path_matches_group(const struct tomoyo_path_info *pathname,
 151                               const struct tomoyo_path_group *group,
 152                               const bool may_use_pattern)
 153{
 154        struct tomoyo_path_group_member *member;
 155        bool matched = false;
 156        list_for_each_entry_rcu(member, &group->member_list, list) {
 157                if (member->is_deleted)
 158                        continue;
 159                if (!member->member_name->is_patterned) {
 160                        if (tomoyo_pathcmp(pathname, member->member_name))
 161                                continue;
 162                } else if (may_use_pattern) {
 163                        if (!tomoyo_path_matches_pattern(pathname,
 164                                                         member->member_name))
 165                                continue;
 166                } else
 167                        continue;
 168                matched = true;
 169                break;
 170        }
 171        return matched;
 172}
 173