1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Landlock LSM - Access types and helpers 4 * 5 * Copyright © 2016-2020 Mickaël Salaün <mic@digikod.net> 6 * Copyright © 2018-2020 ANSSI 7 * Copyright © 2024-2025 Microsoft Corporation 8 */ 9 10 #ifndef _SECURITY_LANDLOCK_ACCESS_H 11 #define _SECURITY_LANDLOCK_ACCESS_H 12 13 #include <linux/bitops.h> 14 #include <linux/build_bug.h> 15 #include <linux/kernel.h> 16 #include <uapi/linux/landlock.h> 17 18 #include "limits.h" 19 20 /* 21 * All access rights that are denied by default whether they are handled or not 22 * by a ruleset/layer. This must be ORed with all ruleset->access_masks[] 23 * entries when we need to get the absolute handled access masks. 24 */ 25 /* clang-format off */ 26 #define _LANDLOCK_ACCESS_FS_INITIALLY_DENIED ( \ 27 LANDLOCK_ACCESS_FS_REFER) 28 /* clang-format on */ 29 30 typedef u16 access_mask_t; 31 32 /* Makes sure all filesystem access rights can be stored. */ 33 static_assert(BITS_PER_TYPE(access_mask_t) >= LANDLOCK_NUM_ACCESS_FS); 34 /* Makes sure all network access rights can be stored. */ 35 static_assert(BITS_PER_TYPE(access_mask_t) >= LANDLOCK_NUM_ACCESS_NET); 36 /* Makes sure all scoped rights can be stored. */ 37 static_assert(BITS_PER_TYPE(access_mask_t) >= LANDLOCK_NUM_SCOPE); 38 /* Makes sure for_each_set_bit() and for_each_clear_bit() calls are OK. */ 39 static_assert(sizeof(unsigned long) >= sizeof(access_mask_t)); 40 41 /* Ruleset access masks. */ 42 struct access_masks { 43 access_mask_t fs : LANDLOCK_NUM_ACCESS_FS; 44 access_mask_t net : LANDLOCK_NUM_ACCESS_NET; 45 access_mask_t scope : LANDLOCK_NUM_SCOPE; 46 }; 47 48 union access_masks_all { 49 struct access_masks masks; 50 u32 all; 51 }; 52 53 /* Makes sure all fields are covered. */ 54 static_assert(sizeof(typeof_member(union access_masks_all, masks)) == 55 sizeof(typeof_member(union access_masks_all, all))); 56 57 typedef u16 layer_mask_t; 58 59 /* Makes sure all layers can be checked. */ 60 static_assert(BITS_PER_TYPE(layer_mask_t) >= LANDLOCK_MAX_NUM_LAYERS); 61 62 #endif /* _SECURITY_LANDLOCK_ACCESS_H */ 63