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/* SPDX-License-Identifier: GPL-2.0-only *//* * AppArmor security module * * This file contains AppArmor label definitions * * Copyright 2017 Canonical Ltd. */ #ifndef __AA_LABEL_H#define __AA_LABEL_H #include <linux/atomic.h>#include <linux/audit.h>#include <linux/rbtree.h>#include <linux/rcupdate.h> #include "apparmor.h"#include "lib.h" struct aa_ns;struct aa_ruleset; #define LOCAL_VEC_ENTRIES 8#define DEFINE_VEC(T, V)						\	struct aa_ ## T *(_ ## V ## _localtmp)[LOCAL_VEC_ENTRIES + 1];	\	struct aa_ ## T **(V) #define vec_setup(T, V, N, GFP)						\({									\	if ((N) <= LOCAL_VEC_ENTRIES) {					\		typeof(N) i;						\		(V) = (_ ## V ## _localtmp);				\		for (i = 0; i <= (N); i++)				\			(V)[i] = NULL;					\	} else								\		(V) = kzalloc_objs(struct aa_ ## T *, (N) + 1, (GFP));	\	(V) ? 0 : -ENOMEM;						\}) #define vec_cleanup(T, V, N)						\do {									\	int i;								\	for (i = 0; i < (N); i++) {					\		if (!IS_ERR_OR_NULL((V)[i]))				\			aa_put_ ## T((V)[i]);				\	}								\	if ((V) != _ ## V ## _localtmp)					\		kfree(V);						\} while (0) #define vec_last(VEC, SIZE) ((VEC)[(SIZE) - 1])#define vec_ns(VEC, SIZE) (vec_last((VEC), (SIZE))->ns)#define vec_labelset(VEC, SIZE) (&vec_ns((VEC), (SIZE))->labels)#define cleanup_domain_vec(V, L) cleanup_label_vec((V), (L)->size) struct aa_profile;#define VEC_FLAG_TERMINATE 1int aa_vec_unique(struct aa_profile **vec, int n, int flags);struct aa_label *aa_vec_find_or_create_label(struct aa_profile **vec, int len,					     gfp_t gfp);#define aa_sort_and_merge_vec(N, V) \	aa_sort_and_merge_profiles((N), (struct aa_profile **)(V))  /* struct aa_labelset - set of labels for a namespace * * Labels are reference counted; aa_labelset does not contribute to label * reference counts. Once a label's last refcount is put it is removed from * the set. */struct aa_labelset {	rwlock_t lock; 	struct rb_root root;}; #define __labelset_for_each(LS, N) \	for ((N) = rb_first(&(LS)->root); (N); (N) = rb_next(N)) enum label_flags {	FLAG_HAT = 1,			/* profile is a hat */	FLAG_UNCONFINED = 2,		/* label unconfined only if all */	FLAG_NULL = 4,			/* profile is null learning profile */	FLAG_IX_ON_NAME_ERROR = 8,	/* fallback to ix on name lookup fail */	FLAG_IMMUTIBLE = 0x10,		/* don't allow changes/replacement */	FLAG_USER_DEFINED = 0x20,	/* user based profile - lower privs */	FLAG_NO_LIST_REF = 0x40,	/* list doesn't keep profile ref */	FLAG_NS_COUNT = 0x80,		/* carries NS ref count */	FLAG_IN_TREE = 0x100,		/* label is in tree */	FLAG_PROFILE = 0x200,		/* label is a profile */	FLAG_EXPLICIT = 0x400,		/* explicit static label */	FLAG_STALE = 0x800,		/* replaced/removed */	FLAG_RENAMED = 0x1000,		/* label has renaming in it */	FLAG_REVOKED = 0x2000,		/* label has revocation in it */	FLAG_DEBUG1 = 0x4000,	FLAG_DEBUG2 = 0x8000, 	/* These flags must correspond with PATH_flags */	/* TODO: add new path flags */}; struct aa_label;struct aa_proxy {	struct aa_common_ref count;	struct aa_label __rcu *label;}; struct label_it {	int i, j;}; /* struct aa_label_base - base info of label * @count: ref count of active users * @node: rbtree position * @rcu: rcu callback struct * @proxy: is set to the label that replaced this label * @hname: text representation of the label (MAYBE_NULL) * @flags: stale and other flags - values may change under label set lock * @secid: secid that references this label * @size: number of entries in @ent[] * @mediates: bitmask for label_mediates * profile: label vec when embedded in a profile FLAG_PROFILE is set * rules: variable length rules in a profile FLAG_PROFILE is set * vec: vector of profiles comprising the compound label */struct aa_label {	struct aa_common_ref count;	struct rb_node node;	struct rcu_head rcu;	struct aa_proxy *proxy;	__counted char *hname;	long flags;	u32 secid;	int size;	u64 mediates;	union {		struct {			/* only used is the label is a profile, size of			 * rules[] is determined by the profile			 * profile[1] is poison or null as guard			 */			struct aa_profile *profile[2];			DECLARE_FLEX_ARRAY(struct aa_ruleset *, rules);		};		DECLARE_FLEX_ARRAY(struct aa_profile *, vec);	};}; #define last_error(E, FN)				\do {							\	int __subE = (FN);				\	if (__subE)					\		(E) = __subE;				\} while (0) #define label_isprofile(X) ((X)->flags & FLAG_PROFILE)#define label_unconfined(X) ((X)->flags & FLAG_UNCONFINED)#define unconfined(X) label_unconfined(X)#define label_is_stale(X) ((X)->flags & FLAG_STALE)#define __label_make_stale(X) ((X)->flags |= FLAG_STALE)#define labels_ns(X) (vec_ns(&((X)->vec[0]), (X)->size))#define labels_set(X) (&labels_ns(X)->labels)#define labels_view(X) labels_ns(X)#define labels_profile(X) ((X)->vec[(X)->size - 1])  int aa_label_next_confined(const struct aa_label *l, int i); /* for each profile in a label */#define label_for_each(I, L, P)						\	for ((I).i = 0; ((P) = (L)->vec[(I).i]); ++((I).i)) /* assumes break/goto ended label_for_each */#define label_for_each_cont(I, L, P)					\	for (++((I).i); ((P) = (L)->vec[(I).i]); ++((I).i))   /* for each profile that is enforcing confinement in a label */#define label_for_each_confined(I, L, P)				\	for ((I).i = aa_label_next_confined((L), 0);			\	     ((P) = (L)->vec[(I).i]);					\	     (I).i = aa_label_next_confined((L), (I).i + 1)) #define label_for_each_in_merge(I, A, B, P)				\	for ((I).i = (I).j = 0;						\	     ((P) = aa_label_next_in_merge(&(I), (A), (B)));		\	     ) #define label_for_each_not_in_set(I, SET, SUB, P)			\	for ((I).i = (I).j = 0;						\	     ((P) = __aa_label_next_not_in_set(&(I), (SET), (SUB)));	\	     ) #define next_in_ns(i, NS, L)						\({									\	typeof(i) ___i = (i);						\	while ((L)->vec[___i] && (L)->vec[___i]->ns != (NS))		\		(___i)++;						\	(___i);								\}) #define label_for_each_in_ns(I, NS, L, P)				\	for ((I).i = next_in_ns(0, (NS), (L));				\	     ((P) = (L)->vec[(I).i]);					\	     (I).i = next_in_ns((I).i + 1, (NS), (L))) #define fn_for_each_in_ns(L, P, FN)					\({									\	struct label_it __i;						\	struct aa_ns *__ns = labels_ns(L);				\	int __E = 0;							\	label_for_each_in_ns(__i, __ns, (L), (P)) {			\		last_error(__E, (FN));					\	}								\	__E;								\})  #define fn_for_each_XXX(L, P, FN, ...)					\({									\	struct label_it i;						\	int __E = 0;							\	label_for_each ## __VA_ARGS__(i, (L), (P)) {			\		last_error(__E, (FN));					\	}								\	__E;								\}) #define fn_for_each(L, P, FN) fn_for_each_XXX(L, P, FN)#define fn_for_each_confined(L, P, FN) fn_for_each_XXX(L, P, FN, _confined) #define fn_for_each2_XXX(L1, L2, P, FN, ...)				\({									\	struct label_it i;						\	int __E = 0;							\	label_for_each ## __VA_ARGS__(i, (L1), (L2), (P)) {		\		last_error(__E, (FN));					\	}								\	__E;								\}) #define fn_for_each_in_merge(L1, L2, P, FN)				\	fn_for_each2_XXX((L1), (L2), P, FN, _in_merge)#define fn_for_each_not_in_set(L1, L2, P, FN)				\	fn_for_each2_XXX((L1), (L2), P, FN, _not_in_set) static inline bool label_mediates(const struct aa_label *L, unsigned char C){	return (L)->mediates & (((u64) 1) << (C));} static inline bool label_mediates_safe(const struct aa_label *L, unsigned char C){	if (C > AA_CLASS_LAST)		return false;	return label_mediates(L, C);} void aa_labelset_destroy(struct aa_labelset *ls);void aa_labelset_init(struct aa_labelset *ls);void __aa_labelset_update_subtree(struct aa_ns *ns); void aa_label_destroy(struct aa_label *label);void aa_label_free(struct aa_label *label);void aa_label_kref(struct kref *kref);bool aa_label_init(struct aa_label *label, int size, gfp_t gfp);struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp); bool aa_label_is_subset(const struct aa_label *set, const struct aa_label *sub);bool aa_label_is_unconfined_subset(const struct aa_label *set,				   const struct aa_label *sub);struct aa_profile *__aa_label_next_not_in_set(struct label_it *I,					     const struct aa_label *set,					     const struct aa_label *sub);bool aa_label_remove(struct aa_label *label);struct aa_label *aa_label_insert(struct aa_labelset *ls, struct aa_label *l);bool aa_label_replace(struct aa_label *old, struct aa_label *new);bool aa_label_make_newest(struct aa_labelset *ls, struct aa_label *old,			  struct aa_label *new); struct aa_profile *aa_label_next_in_merge(struct label_it *I,					  const struct aa_label *a,					  const struct aa_label *b);struct aa_label *aa_label_find_merge(struct aa_label *a, struct aa_label *b);struct aa_label *aa_label_merge(struct aa_label *a, struct aa_label *b,				gfp_t gfp);  bool aa_update_label_name(struct aa_ns *ns, struct aa_label *label, gfp_t gfp); #define FLAGS_NONE 0#define FLAG_SHOW_MODE 1#define FLAG_VIEW_SUBNS 2#define FLAG_HIDDEN_UNCONFINED 4#define FLAG_ABS_ROOT 8int aa_label_snxprint(char *str, size_t size, struct aa_ns *view,		      struct aa_label *label, int flags);int aa_label_asxprint(char **strp, struct aa_ns *ns, struct aa_label *label,		      int flags, gfp_t gfp);int aa_label_acntsxprint(char __counted **strp, struct aa_ns *ns,			 struct aa_label *label, int flags, gfp_t gfp);void aa_label_xaudit(struct audit_buffer *ab, struct aa_ns *ns,		     struct aa_label *label, int flags, gfp_t gfp);void aa_label_seq_xprint(struct seq_file *f, struct aa_ns *ns,			 struct aa_label *label, int flags, gfp_t gfp);void aa_label_xprintk(struct aa_ns *ns, struct aa_label *label, int flags,		      gfp_t gfp);void aa_label_printk(struct aa_label *label, gfp_t gfp); struct aa_label *aa_label_strn_parse(struct aa_label *base, const char *str,				     size_t n, gfp_t gfp, bool create,				     bool force_stack);struct aa_label *aa_label_parse(struct aa_label *base, const char *str,				gfp_t gfp, bool create, bool force_stack); static inline const char *aa_label_strn_split(const char *str, int n){	const char *pos;	aa_state_t state; 	state = aa_dfa_matchn_until(stacksplitdfa, DFA_START, str, n, &pos);	if (!ACCEPT_TABLE(stacksplitdfa)[state])		return NULL; 	return pos - 3;} static inline const char *aa_label_str_split(const char *str){	const char *pos;	aa_state_t state; 	state = aa_dfa_match_until(stacksplitdfa, DFA_START, str, &pos);	if (!ACCEPT_TABLE(stacksplitdfa)[state])		return NULL; 	return pos - 3;}   struct aa_perms;struct aa_ruleset;int aa_label_match(const struct aa_profile *profile, struct aa_ruleset *rules,		   struct aa_label *label, aa_state_t state, bool subns,		   u32 request, struct aa_perms *perms);  /** * __aa_get_label - get a reference count to uncounted label reference * @l: reference to get a count on * * Returns: pointer to reference OR NULL if race is lost and reference is *          being repeated. * Requires: lock held, and the return code MUST be checked */static inline struct aa_label *__aa_get_label(struct aa_label *l){	if (l && kref_get_unless_zero(&l->count.count))		return l; 	return NULL;} static inline struct aa_label *aa_get_label(struct aa_label *l){	if (l)		kref_get(&(l->count.count)); 	return l;}  /** * aa_get_label_rcu - increment refcount on a label that can be replaced * @l: pointer to label that can be replaced (NOT NULL) * * Returns: pointer to a refcounted label. *     else NULL if no label */static inline struct aa_label *aa_get_label_rcu(struct aa_label __rcu **l){	struct aa_label *c; 	rcu_read_lock();	do {		c = rcu_dereference(*l);	} while (c && !kref_get_unless_zero(&c->count.count));	rcu_read_unlock(); 	return c;} /** * aa_get_newest_label - find the newest version of @l * @l: the label to check for newer versions of * * Returns: refcounted newest version of @l taking into account *          replacement, renames and removals *          return @l. */static inline struct aa_label *aa_get_newest_label(struct aa_label *l){	if (!l)		return NULL; 	if (label_is_stale(l)) {		struct aa_label *tmp; 		AA_BUG(!l->proxy);		AA_BUG(!l->proxy->label);		/* BUG: only way this can happen is @l ref count and its		 * replacement count have gone to 0 and are on their way		 * to destruction. ie. we have a refcounting error		 */		tmp = aa_get_label_rcu(&l->proxy->label);		AA_BUG(!tmp); 		return tmp;	} 	return aa_get_label(l);} /** * aa_get_newest_label_condref - find the newest version of @l * @l: the label to check for newer versions of * @needput: returns whether the reference needs put * * Returns: refcounted newest version of @l taking into account *          replacement, renames and removals *          return @l. */static inline struct aa_label *aa_get_newest_label_condref(struct aa_label *l,							   bool *needput){	if (l && unlikely(label_is_stale(l))) {		struct aa_label *tmp; 		AA_BUG(!l->proxy);		AA_BUG(!l->proxy->label);		/* BUG: only way this can happen is @l ref count and its		 * replacement count have gone to 0 and are on their way		 * to destruction. ie. we have a refcounting error		 */		tmp = aa_get_label_rcu(&l->proxy->label);		AA_BUG(!tmp); 		*needput = true;		return tmp;	} 	*needput = false;	return l;} static inline void aa_put_label(struct aa_label *l){	if (l)		kref_put(&l->count.count, aa_label_kref);} /* wrapper fn to indicate semantics of the check */static inline bool __aa_subj_label_is_cached(const struct aa_label *subj_label,					  const struct aa_label *obj_label){	return aa_label_is_subset(obj_label, subj_label);}  struct aa_proxy *aa_alloc_proxy(struct aa_label *l, gfp_t gfp);void aa_proxy_kref(struct kref *kref); static inline struct aa_proxy *aa_get_proxy(struct aa_proxy *proxy){	if (proxy)		kref_get(&(proxy->count.count)); 	return proxy;} static inline void aa_put_proxy(struct aa_proxy *proxy){	if (proxy)		kref_put(&proxy->count.count, aa_proxy_kref);} void __aa_proxy_redirect(struct aa_label *orig, struct aa_label *new); #endif /* __AA_LABEL_H */