apparmor: extend permissions to support a label and tag string

add indexes for label and tag entries. Rename the domain table to the
str_table as its a shared string table with label and tags.
Signed-off-by: John Johansen <john.johansen@canonical.com>

security/apparmor/domain.c

@@ -29,24 +29,6 @@
 #include "include/policy.h"
 #include "include/policy_ns.h"
 
-/**
- * aa_free_domain_entries - free entries in a domain table
- * @domain: the domain table to free  (MAYBE NULL)
- */
-void aa_free_domain_entries(struct aa_domain *domain)
-{
-	int i;
-	if (domain) {
-		if (!domain->table)
-			return;
-
-		for (i = 0; i < domain->size; i++)
-			kfree_sensitive(domain->table[i]);
-		kfree_sensitive(domain->table);
-		domain->table = NULL;
-	}
-}
-
 /**
  * may_change_ptraced_domain - check if can change profile on ptraced task
  * @to_label: profile to change to  (NOT NULL)

security/apparmor/include/domain.h

@@ -16,11 +16,6 @@
 #ifndef __AA_DOMAIN_H
 #define __AA_DOMAIN_H
 
-struct aa_domain {
-	int size;
-	char **table;
-};
-
 #define AA_CHANGE_NOFLAGS 0
 #define AA_CHANGE_TEST 1
 #define AA_CHANGE_CHILD 2
@@ -32,7 +27,6 @@ struct aa_label *x_table_lookup(struct aa_profile *profile, u32 xindex,
 
 int apparmor_bprm_creds_for_exec(struct linux_binprm *bprm);
 
-void aa_free_domain_entries(struct aa_domain *domain);
 int aa_change_hat(const char *hats[], int count, u64 token, int flags);
 int aa_change_profile(const char *fqname, int flags);
 

security/apparmor/include/lib.h

@@ -99,6 +99,12 @@ static inline bool path_mediated_fs(struct dentry *dentry)
 	return !(dentry->d_sb->s_flags & SB_NOUSER);
 }
 
+struct aa_str_table {
+	int size;
+	char **table;
+};
+
+void aa_free_str_table(struct aa_str_table *table);
 
 struct counted_str {
 	struct kref count;

security/apparmor/include/perms.h

@@ -79,6 +79,8 @@ struct aa_perms {
 	u32 hide;	/* set only when  ~allow | deny */
 
 	u32 xindex;
+	u32 tag;	/* tag string index, if present */
+	u32 label;	/* label string index, if present */
 };
 
 #define ALL_PERMS_MASK 0xffffffff

security/apparmor/include/policy.h

@@ -72,12 +72,14 @@ enum profile_mode {
 
 /* struct aa_policydb - match engine for a policy
  * dfa: dfa pattern match
+ * perms: table of permissions
+ * strs: table of strings, index by x
  * start: set of start states for the different classes of data
  */
 struct aa_policydb {
 	struct aa_dfa *dfa;
 	struct aa_perms *perms;
-	struct aa_domain trans;
+	struct aa_str_table trans;
 	aa_state_t start[AA_CLASS_LAST + 1];
 };
 
@@ -86,7 +88,7 @@ static inline void aa_destroy_policydb(struct aa_policydb *policy)
 	aa_put_dfa(policy->dfa);
 	if (policy->perms)
 		kvfree(policy->perms);
-	aa_free_domain_entries(&policy->trans);
+	aa_free_str_table(&policy->trans);
 
 }
 

security/apparmor/lib.c

@@ -25,6 +25,25 @@ struct aa_perms allperms = { .allow = ALL_PERMS_MASK,
 			     .quiet = ALL_PERMS_MASK,
 			     .hide = ALL_PERMS_MASK };
 
+/**
+ * aa_free_str_table - free entries str table
+ * @str: the string table to free  (MAYBE NULL)
+ */
+void aa_free_str_table(struct aa_str_table *t)
+{
+	int i;
+
+	if (t) {
+		if (!t->table)
+			return;
+
+		for (i = 0; i < t->size; i++)
+			kfree_sensitive(t->table[i]);
+		kfree_sensitive(t->table);
+		t->table = NULL;
+	}
+}
+
 /**
  * aa_split_fqname - split a fqname into a profile and namespace name
  * @fqname: a full qualified name in namespace profile format (NOT NULL)

security/apparmor/policy_unpack.c

@@ -534,7 +534,7 @@ static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
 	return true;
 
 fail:
-	aa_free_domain_entries(&profile->file.trans);
+	aa_free_str_table(&profile->file.trans);
 	e->pos = saved_pos;
 	return false;
 }