diff options
Diffstat (limited to 'security/landlock/ruleset.h')
| -rw-r--r-- | security/landlock/ruleset.h | 118 |
1 files changed, 55 insertions, 63 deletions
diff --git a/security/landlock/ruleset.h b/security/landlock/ruleset.h index c7f1526784fd..5da9a64f5af7 100644 --- a/security/landlock/ruleset.h +++ b/security/landlock/ruleset.h @@ -9,44 +9,18 @@ #ifndef _SECURITY_LANDLOCK_RULESET_H #define _SECURITY_LANDLOCK_RULESET_H -#include <linux/bitops.h> -#include <linux/build_bug.h> +#include <linux/cleanup.h> +#include <linux/err.h> #include <linux/mutex.h> #include <linux/rbtree.h> #include <linux/refcount.h> #include <linux/workqueue.h> -#include <uapi/linux/landlock.h> +#include "access.h" #include "limits.h" #include "object.h" -/* - * All access rights that are denied by default whether they are handled or not - * by a ruleset/layer. This must be ORed with all ruleset->access_masks[] - * entries when we need to get the absolute handled access masks. - */ -/* clang-format off */ -#define LANDLOCK_ACCESS_FS_INITIALLY_DENIED ( \ - LANDLOCK_ACCESS_FS_REFER) -/* clang-format on */ - -typedef u16 access_mask_t; -/* Makes sure all filesystem access rights can be stored. */ -static_assert(BITS_PER_TYPE(access_mask_t) >= LANDLOCK_NUM_ACCESS_FS); -/* Makes sure all network access rights can be stored. */ -static_assert(BITS_PER_TYPE(access_mask_t) >= LANDLOCK_NUM_ACCESS_NET); -/* Makes sure for_each_set_bit() and for_each_clear_bit() calls are OK. */ -static_assert(sizeof(unsigned long) >= sizeof(access_mask_t)); - -/* Ruleset access masks. */ -typedef u32 access_masks_t; -/* Makes sure all ruleset access rights can be stored. */ -static_assert(BITS_PER_TYPE(access_masks_t) >= - LANDLOCK_NUM_ACCESS_FS + LANDLOCK_NUM_ACCESS_NET); - -typedef u16 layer_mask_t; -/* Makes sure all layers can be checked. */ -static_assert(BITS_PER_TYPE(layer_mask_t) >= LANDLOCK_MAX_NUM_LAYERS); +struct landlock_hierarchy; /** * struct landlock_layer - Access rights for a given layer @@ -137,22 +111,6 @@ struct landlock_rule { }; /** - * struct landlock_hierarchy - Node in a ruleset hierarchy - */ -struct landlock_hierarchy { - /** - * @parent: Pointer to the parent node, or NULL if it is a root - * Landlock domain. - */ - struct landlock_hierarchy *parent; - /** - * @usage: Number of potential children domains plus their parent - * domain. - */ - refcount_t usage; -}; - -/** * struct landlock_ruleset - Landlock ruleset * * This data structure must contain unique entries, be updatable, and quick to @@ -226,18 +184,22 @@ struct landlock_ruleset { * layers are set once and never changed for the * lifetime of the ruleset. */ - access_masks_t access_masks[]; + struct access_masks access_masks[]; }; }; }; struct landlock_ruleset * landlock_create_ruleset(const access_mask_t access_mask_fs, - const access_mask_t access_mask_net); + const access_mask_t access_mask_net, + const access_mask_t scope_mask); void landlock_put_ruleset(struct landlock_ruleset *const ruleset); void landlock_put_ruleset_deferred(struct landlock_ruleset *const ruleset); +DEFINE_FREE(landlock_put_ruleset, struct landlock_ruleset *, + if (!IS_ERR_OR_NULL(_T)) landlock_put_ruleset(_T)) + int landlock_insert_rule(struct landlock_ruleset *const ruleset, const struct landlock_id id, const access_mask_t access); @@ -256,6 +218,31 @@ static inline void landlock_get_ruleset(struct landlock_ruleset *const ruleset) refcount_inc(&ruleset->usage); } +/** + * landlock_union_access_masks - Return all access rights handled in the + * domain + * + * @domain: Landlock ruleset (used as a domain) + * + * Returns: an access_masks result of the OR of all the domain's access masks. + */ +static inline struct access_masks +landlock_union_access_masks(const struct landlock_ruleset *const domain) +{ + union access_masks_all matches = {}; + size_t layer_level; + + for (layer_level = 0; layer_level < domain->num_layers; layer_level++) { + union access_masks_all layer = { + .masks = domain->access_masks[layer_level], + }; + + matches.all |= layer.all; + } + + return matches.masks; +} + static inline void landlock_add_fs_access_mask(struct landlock_ruleset *const ruleset, const access_mask_t fs_access_mask, @@ -265,8 +252,7 @@ landlock_add_fs_access_mask(struct landlock_ruleset *const ruleset, /* Should already be checked in sys_landlock_create_ruleset(). */ WARN_ON_ONCE(fs_access_mask != fs_mask); - ruleset->access_masks[layer_level] |= - (fs_mask << LANDLOCK_SHIFT_ACCESS_FS); + ruleset->access_masks[layer_level].fs |= fs_mask; } static inline void @@ -278,17 +264,18 @@ landlock_add_net_access_mask(struct landlock_ruleset *const ruleset, /* Should already be checked in sys_landlock_create_ruleset(). */ WARN_ON_ONCE(net_access_mask != net_mask); - ruleset->access_masks[layer_level] |= - (net_mask << LANDLOCK_SHIFT_ACCESS_NET); + ruleset->access_masks[layer_level].net |= net_mask; } -static inline access_mask_t -landlock_get_raw_fs_access_mask(const struct landlock_ruleset *const ruleset, - const u16 layer_level) +static inline void +landlock_add_scope_mask(struct landlock_ruleset *const ruleset, + const access_mask_t scope_mask, const u16 layer_level) { - return (ruleset->access_masks[layer_level] >> - LANDLOCK_SHIFT_ACCESS_FS) & - LANDLOCK_MASK_ACCESS_FS; + access_mask_t mask = scope_mask & LANDLOCK_MASK_SCOPE; + + /* Should already be checked in sys_landlock_create_ruleset(). */ + WARN_ON_ONCE(scope_mask != mask); + ruleset->access_masks[layer_level].scope |= mask; } static inline access_mask_t @@ -296,17 +283,22 @@ landlock_get_fs_access_mask(const struct landlock_ruleset *const ruleset, const u16 layer_level) { /* Handles all initially denied by default access rights. */ - return landlock_get_raw_fs_access_mask(ruleset, layer_level) | - LANDLOCK_ACCESS_FS_INITIALLY_DENIED; + return ruleset->access_masks[layer_level].fs | + _LANDLOCK_ACCESS_FS_INITIALLY_DENIED; } static inline access_mask_t landlock_get_net_access_mask(const struct landlock_ruleset *const ruleset, const u16 layer_level) { - return (ruleset->access_masks[layer_level] >> - LANDLOCK_SHIFT_ACCESS_NET) & - LANDLOCK_MASK_ACCESS_NET; + return ruleset->access_masks[layer_level].net; +} + +static inline access_mask_t +landlock_get_scope_mask(const struct landlock_ruleset *const ruleset, + const u16 layer_level) +{ + return ruleset->access_masks[layer_level].scope; } bool landlock_unmask_layers(const struct landlock_rule *const rule, |