LXR linux/security/safesetid/lsm.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * SafeSetID Linux Security Module
   4 *
   5 * Author: Micah Morton <mortonm@chromium.org>
   6 *
   7 * Copyright (C) 2018 The Chromium OS Authors.
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2, as
  11 * published by the Free Software Foundation.
  12 *
  13 */
  14#ifndef _SAFESETID_H
  15#define _SAFESETID_H
  16
  17#include <linux/types.h>
  18#include <linux/uidgid.h>
  19#include <linux/hashtable.h>
  20
  21/* Flag indicating whether initialization completed */
  22extern int safesetid_initialized __initdata;
  23
  24enum sid_policy_type {
  25        SIDPOL_DEFAULT, /* source ID is unaffected by policy */
  26        SIDPOL_CONSTRAINED, /* source ID is affected by policy */
  27        SIDPOL_ALLOWED /* target ID explicitly allowed */
  28};
  29
  30typedef union {
  31        kuid_t uid;
  32        kgid_t gid;
  33} kid_t;
  34
  35enum setid_type {
  36        UID,
  37        GID
  38};
  39
  40/*
  41 * Hash table entry to store safesetid policy signifying that 'src_id'
  42 * can set*id to 'dst_id'.
  43 */
  44struct setid_rule {
  45        struct hlist_node next;
  46        kid_t src_id;
  47        kid_t dst_id;
  48
  49        /* Flag to signal if rule is for UID's or GID's */
  50        enum setid_type type;
  51};
  52
  53#define SETID_HASH_BITS 8 /* 256 buckets in hash table */
  54
  55/* Extension of INVALID_UID/INVALID_GID for kid_t type */
  56#define INVALID_ID (kid_t){.uid = INVALID_UID}
  57
  58struct setid_ruleset {
  59        DECLARE_HASHTABLE(rules, SETID_HASH_BITS);
  60        char *policy_str;
  61        struct rcu_head rcu;
  62
  63        //Flag to signal if ruleset is for UID's or GID's
  64        enum setid_type type;
  65};
  66
  67enum sid_policy_type _setid_policy_lookup(struct setid_ruleset *policy,
  68                kid_t src, kid_t dst);
  69
  70extern struct setid_ruleset __rcu *safesetid_setuid_rules;
  71extern struct setid_ruleset __rcu *safesetid_setgid_rules;
  72
  73#endif /* _SAFESETID_H */
  74