[PATCH 06/10] libsepol/cil: Refactored CIL neverallow checking and reporting.

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Use the libsepol neverallow checking to determine if a given neverallow
rule is violated. If a violation is found, use the function
cil_find_matching_avrule_in_ast() to find the AST node of the particular
rule that violates the neverallow. This allows CIL to provide a more
informative error message that includes the file and line number of the
node and all of its parents.

Example error report:
Neverallow check failed at line 31285 of cil.conf.neverallow
  (neverallow typeset4 self (memprotect (mmap_zero)))
    <root>
    booleanif at line 152094 of cil.conf.neverallow
    true at line 152095 of cil.conf.neverallow
    allow at line 152096 of cil.conf.neverallow
      (allow ada_t self (memprotect (mmap_zero)))

Signed-off-by: James Carter <jwcart2@xxxxxxxxxxxxx>
---
 libsepol/cil/src/cil_binary.c | 485 ++++++++++++++++++++++++++++--------------
 libsepol/cil/src/cil_binary.h |   4 +-
 2 files changed, 323 insertions(+), 166 deletions(-)

diff --git a/libsepol/cil/src/cil_binary.c b/libsepol/cil/src/cil_binary.c
index 03f4924..806f711 100644
--- a/libsepol/cil/src/cil_binary.c
+++ b/libsepol/cil/src/cil_binary.c
@@ -37,6 +37,8 @@
 #include <sepol/policydb/conditional.h>
 #include <sepol/policydb/constraint.h>
 #include <sepol/policydb/flask.h>
+#include <sepol/policydb/expand.h>
+#include <sepol/policydb/hierarchy.h>
 
 #include "cil_internal.h"
 #include "cil_flavor.h"
@@ -45,6 +47,7 @@
 #include "cil_tree.h"
 #include "cil_binary.h"
 #include "cil_symtab.h"
+#include "cil_find.h"
 
 /* There are 44000 filename_trans in current fedora policy. 1.33 times this is the recommended
  * size of a hashtable. The next power of 2 of this is 2 ** 16.
@@ -68,39 +71,9 @@ struct cil_args_booleanif {
 	policydb_t *pdb;
 	cond_node_t *cond_node;
 	enum cil_flavor cond_flavor;
-	struct cil_list *neverallows;
 	hashtab_t filename_trans_table;
 };
 
-struct cil_neverallow {
-	struct cil_tree_node *node;
-	struct cil_list *rules;
-};
-
-struct cil_neverallow_rule {
-	struct cil_symtab_datum *src;
-	struct cil_symtab_datum *tgt;
-	uint32_t class;
-	uint32_t perms;
-};
-
-void cil_neverallows_list_destroy(struct cil_list *neverallows)
-{
-	struct cil_list_item *i;
-	struct cil_list_item *j;
-
-	cil_list_for_each(i, neverallows) {
-		struct cil_neverallow *neverallow = i->data;
-		cil_list_for_each(j, neverallow->rules) {
-			struct cil_neverallow_rule *rule = j->data;
-			free(rule);
-		}
-		cil_list_destroy(&neverallow->rules, CIL_FALSE);
-		free(neverallow);
-	}
-	cil_list_destroy(&neverallows, CIL_FALSE);
-}
-
 static int __cil_get_sepol_user_datum(policydb_t *pdb, struct cil_symtab_datum *datum, user_datum_t **sepol_user)
 {
 	*sepol_user = hashtab_search(pdb->p_users.table, datum->fqn);
@@ -628,14 +601,21 @@ int __cil_typeattr_bitmap_init(policydb_t *pdb)
 	int rc = SEPOL_ERR;
 
 	pdb->type_attr_map = cil_malloc(pdb->p_types.nprim * sizeof(ebitmap_t));
+	pdb->attr_type_map = cil_malloc(pdb->p_types.nprim * sizeof(ebitmap_t));
 
 	uint32_t i = 0;
 	for (i = 0; i < pdb->p_types.nprim; i++) {
 		ebitmap_init(&pdb->type_attr_map[i]);
+		ebitmap_init(&pdb->attr_type_map[i]);
 		if (ebitmap_set_bit(&pdb->type_attr_map[i], i, 1)) {
 			rc = SEPOL_ERR;
 			goto exit;
 		}
+		if (ebitmap_set_bit(&pdb->attr_type_map[i], i, 1)) {
+			rc = SEPOL_ERR;
+			goto exit;
+		}
+
 	}
 
 	return SEPOL_OK;
@@ -675,6 +655,7 @@ int cil_typeattribute_to_bitmap(policydb_t *pdb, const struct cil_db *db, struct
 		if (rc != SEPOL_OK) goto exit;
 
 		ebitmap_set_bit(&pdb->type_attr_map[sepol_type->s.value - 1], value - 1, 1);
+		ebitmap_set_bit(&pdb->attr_type_map[value - 1], sepol_type->s.value - 1, 1);
 	}
 
 	rc = SEPOL_OK;
@@ -1324,89 +1305,7 @@ exit:
 	return rc;
 }
 
-static void __cil_neverallow_handle(struct cil_list *neverallows, struct cil_symtab_datum *src, struct cil_symtab_datum *tgt, uint32_t class, uint32_t perms)
-{
-	struct cil_neverallow *neverallow = neverallows->head->data;
-	struct cil_list *neverallow_rules = neverallow->rules;
-	struct cil_neverallow_rule *new = NULL;
-
-	new = cil_malloc(sizeof(*new));
-	new->src = src;
-	new->tgt = tgt;
-	new->class = class;
-	new->perms = perms;
-
-	cil_list_append(neverallow_rules, CIL_LIST_ITEM, new);
-}
-
-static int __cil_is_type_match(enum cil_flavor f1, struct cil_symtab_datum *t1, enum cil_flavor f2, struct cil_symtab_datum *t2)
-{
-	if (t1->fqn == t2->fqn) {
-		return CIL_TRUE;
-	} else if (f1 == CIL_TYPEATTRIBUTE && f2 != CIL_TYPEATTRIBUTE) {
-		struct cil_typeattribute *a = (struct cil_typeattribute *)t1;
-		struct cil_type *t = (struct cil_type *)t2;
-		if (ebitmap_get_bit(a->types, t->value)) {
-			return CIL_TRUE;
-		}
-	} else if (f1 != CIL_TYPEATTRIBUTE && f2 == CIL_TYPEATTRIBUTE) {
-		struct cil_typeattribute *a = (struct cil_typeattribute *)t2;
-		struct cil_type *t = (struct cil_type *)t1;
-		if (ebitmap_get_bit(a->types, t->value)) {
-			return CIL_TRUE;
-		}
-	} else if (f1 == CIL_TYPEATTRIBUTE && f2 == CIL_TYPEATTRIBUTE) {
-		struct cil_typeattribute *a1 = (struct cil_typeattribute *)t2;
-		struct cil_typeattribute *a2 = (struct cil_typeattribute *)t1;
-		/* abusing the ebitmap abstraction for speed */
-		ebitmap_node_t *n1 = a1->types->node;
-		ebitmap_node_t *n2 = a2->types->node;
-		while (n1 && n2) {
-			if (n1->startbit < n2->startbit) {
-				n1 = n1->next;
-			} else if (n2->startbit < n1->startbit) {
-				n2 = n2->next;
-			} else {
-				if (n1->map & n2->map) {
-					return CIL_TRUE;
-				}
-				n1 = n1->next;
-				n2 = n2->next;
-			}
-		}
-	}
-	return CIL_FALSE;
-}
-
-static int __cil_check_neverallows(struct cil_list *neverallows, struct cil_symtab_datum *src, struct cil_symtab_datum *tgt, uint32_t class, uint32_t perms)
-{
-	struct cil_list_item *curr = NULL;
-	enum cil_flavor al_src_flavor = ((struct cil_tree_node*)src->nodes->head->data)->flavor;
-	enum cil_flavor al_tgt_flavor = ((struct cil_tree_node*)tgt->nodes->head->data)->flavor;
-	cil_list_for_each(curr, neverallows) {
-		struct cil_neverallow *neverallow = curr->data;
-		struct cil_tree_node *node = neverallow->node;
-		struct cil_list_item *curr_item = NULL;
-		cil_list_for_each(curr_item, neverallow->rules) {
-			struct cil_neverallow_rule *curr_rule = curr_item->data;
-			enum cil_flavor nv_src_flavor = ((struct cil_tree_node*)curr_rule->src->nodes->head->data)->flavor;
-			enum cil_flavor nv_tgt_flavor = ((struct cil_tree_node*)curr_rule->tgt->nodes->head->data)->flavor;
-			if ((curr_rule->perms & perms) && (class == curr_rule->class)) {
-				int src_match = __cil_is_type_match(al_src_flavor, src, nv_src_flavor, curr_rule->src);
-				if (src_match) {
-					int tgt_match = __cil_is_type_match(al_tgt_flavor, tgt, nv_tgt_flavor, curr_rule->tgt);
-					if (tgt_match) {
-						cil_log(CIL_ERR, "Neverallow found that matches avrule at line %d of %s\n", node->line, node->path);
-						return SEPOL_ERR;
-					}
-				}
-			}
-		}
-	}
-	return SEPOL_OK;
-}
-
-int __cil_avrule_expand_helper(policydb_t *pdb, uint16_t kind, struct cil_symtab_datum *src, struct cil_symtab_datum *tgt, struct cil_classperms *cp, struct cil_list *neverallows, cond_node_t *cond_node, enum cil_flavor cond_flavor)
+int __cil_avrule_expand_helper(policydb_t *pdb, uint16_t kind, struct cil_symtab_datum *src, struct cil_symtab_datum *tgt, struct cil_classperms *cp, cond_node_t *cond_node, enum cil_flavor cond_flavor)
 {
 	int rc = SEPOL_ERR;
 	type_datum_t *sepol_src = NULL;
@@ -1425,28 +1324,19 @@ int __cil_avrule_expand_helper(policydb_t *pdb, uint16_t kind, struct cil_symtab
 		return SEPOL_OK;
 	}
 
-	if (kind == CIL_AVRULE_NEVERALLOW) {
-		__cil_neverallow_handle(neverallows, src, tgt, sepol_class->s.value, data);
-	} else {
-		if (kind == CIL_AVRULE_DONTAUDIT) {
-			data = ~data;
-		} else if (neverallows != NULL && kind == CIL_AVRULE_ALLOWED) {
-			rc = __cil_check_neverallows(neverallows, src, tgt, sepol_class->s.value, data);
-			if (rc != SEPOL_OK) {
-				goto exit;
-			}
-		}
+	if (kind == CIL_AVRULE_DONTAUDIT) {
+		data = ~data;
+	}
 
-		rc = __cil_get_sepol_type_datum(pdb, src, &sepol_src);
-		if (rc != SEPOL_OK) goto exit;
+	rc = __cil_get_sepol_type_datum(pdb, src, &sepol_src);
+	if (rc != SEPOL_OK) goto exit;
 
-		rc = __cil_get_sepol_type_datum(pdb, tgt, &sepol_tgt);
-		if (rc != SEPOL_OK) goto exit;
+	rc = __cil_get_sepol_type_datum(pdb, tgt, &sepol_tgt);
+	if (rc != SEPOL_OK) goto exit;
 
-		rc = __cil_insert_avrule(pdb, kind, sepol_src->s.value, sepol_tgt->s.value, sepol_class->s.value, data, cond_node, cond_flavor);
-		if (rc != SEPOL_OK) {
-			goto exit;
-		}
+	rc = __cil_insert_avrule(pdb, kind, sepol_src->s.value, sepol_tgt->s.value, sepol_class->s.value, data, cond_node, cond_flavor);
+	if (rc != SEPOL_OK) {
+		goto exit;
 	}
 
 	return SEPOL_OK;
@@ -1456,7 +1346,7 @@ exit:
 }
 
 
-int __cil_avrule_expand(policydb_t *pdb, uint16_t kind, struct cil_symtab_datum *src, struct cil_symtab_datum *tgt, struct cil_list *classperms, struct cil_list *neverallows, cond_node_t *cond_node, enum cil_flavor cond_flavor)
+int __cil_avrule_expand(policydb_t *pdb, uint16_t kind, struct cil_symtab_datum *src, struct cil_symtab_datum *tgt, struct cil_list *classperms, cond_node_t *cond_node, enum cil_flavor cond_flavor)
 {
 	int rc = SEPOL_ERR;
 	struct cil_list_item *curr;
@@ -1465,7 +1355,7 @@ int __cil_avrule_expand(policydb_t *pdb, uint16_t kind, struct cil_symtab_datum
 		if (curr->flavor == CIL_CLASSPERMS) {
 			struct cil_classperms *cp = curr->data;
 			if (FLAVOR(cp->class) == CIL_CLASS) {
-				rc = __cil_avrule_expand_helper(pdb, kind, src, tgt, cp, neverallows, cond_node, cond_flavor);
+				rc = __cil_avrule_expand_helper(pdb, kind, src, tgt, cp, cond_node, cond_flavor);
 				if (rc != SEPOL_OK) {
 					goto exit;
 				}
@@ -1473,7 +1363,7 @@ int __cil_avrule_expand(policydb_t *pdb, uint16_t kind, struct cil_symtab_datum
 				struct cil_list_item *i = NULL;
 				cil_list_for_each(i, cp->perms) {
 					struct cil_perm *cmp = i->data;
-					rc = __cil_avrule_expand(pdb, kind, src, tgt, cmp->classperms, neverallows, cond_node, cond_flavor);
+					rc = __cil_avrule_expand(pdb, kind, src, tgt, cmp->classperms, cond_node, cond_flavor);
 					if (rc != SEPOL_OK) {
 						goto exit;
 					}
@@ -1482,7 +1372,7 @@ int __cil_avrule_expand(policydb_t *pdb, uint16_t kind, struct cil_symtab_datum
 		} else { /* SET */
 			struct cil_classperms_set *cp_set = curr->data;
 			struct cil_classpermission *cp = cp_set->set;
-			rc = __cil_avrule_expand(pdb, kind, src, tgt, cp->classperms, neverallows, cond_node, cond_flavor);
+			rc = __cil_avrule_expand(pdb, kind, src, tgt, cp->classperms, cond_node, cond_flavor);
 			if (rc != SEPOL_OK) {
 				goto exit;
 			}
@@ -1495,7 +1385,7 @@ exit:
 	return rc;
 }
 
-int __cil_avrule_to_avtab(policydb_t *pdb, const struct cil_db *db, struct cil_avrule *cil_avrule, struct cil_list *neverallows, cond_node_t *cond_node, enum cil_flavor cond_flavor)
+int __cil_avrule_to_avtab(policydb_t *pdb, const struct cil_db *db, struct cil_avrule *cil_avrule, cond_node_t *cond_node, enum cil_flavor cond_flavor)
 {
 	int rc = SEPOL_ERR;
 	uint16_t kind = cil_avrule->rule_kind;
@@ -1509,12 +1399,6 @@ int __cil_avrule_to_avtab(policydb_t *pdb, const struct cil_db *db, struct cil_a
 		goto exit;
 	}
 
-	if (cil_avrule->rule_kind == CIL_AVRULE_NEVERALLOW && db->disable_neverallow == CIL_TRUE) {
-		// ignore neverallow rules
-		rc = SEPOL_OK;
-		goto exit;
-	}
-
 	src = cil_avrule->src;
 	tgt = cil_avrule->tgt;
 
@@ -1530,7 +1414,7 @@ int __cil_avrule_to_avtab(policydb_t *pdb, const struct cil_db *db, struct cil_a
 			if (!ebitmap_get_bit(&type_bitmap, i)) continue;
 
 			src = DATUM(db->val_to_type[i]);
-			rc = __cil_avrule_expand(pdb, kind, src, src, classperms, neverallows, cond_node, cond_flavor);
+			rc = __cil_avrule_expand(pdb, kind, src, src, classperms, cond_node, cond_flavor);
 			if (rc != SEPOL_OK) {
 				ebitmap_destroy(&type_bitmap);
 				goto exit;
@@ -1538,7 +1422,7 @@ int __cil_avrule_to_avtab(policydb_t *pdb, const struct cil_db *db, struct cil_a
 		}
 		ebitmap_destroy(&type_bitmap);
 	} else {
-		rc = __cil_avrule_expand(pdb, kind, src, tgt, classperms, neverallows, cond_node, cond_flavor);
+		rc = __cil_avrule_expand(pdb, kind, src, tgt, classperms, cond_node, cond_flavor);
 		if (rc != SEPOL_OK) goto exit;
 	}
 
@@ -1548,9 +1432,9 @@ exit:
 	return rc;
 }
 
-int cil_avrule_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_avrule *cil_avrule, struct cil_list *neverallows)
+int cil_avrule_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_avrule *cil_avrule)
 {
-	return __cil_avrule_to_avtab(pdb, db, cil_avrule, neverallows, NULL, CIL_FALSE);
+	return __cil_avrule_to_avtab(pdb, db, cil_avrule, NULL, CIL_FALSE);
 }
 
 int __cil_cond_to_policydb_helper(struct cil_tree_node *node, __attribute__((unused)) uint32_t *finished, void *extra_args)
@@ -1593,7 +1477,7 @@ int __cil_cond_to_policydb_helper(struct cil_tree_node *node, __attribute__((unu
 		break;
 	case CIL_AVRULE:
 		cil_avrule = node->data;
-		rc = __cil_avrule_to_avtab(pdb, db, cil_avrule, args->neverallows, cond_node, cond_flavor);
+		rc = __cil_avrule_to_avtab(pdb, db, cil_avrule, cond_node, cond_flavor);
 		if (rc != SEPOL_OK) {
 			cil_log(CIL_ERR, "Failed to insert avrule into avtab at line %d of %s\n", node->line, node->path);
 			goto exit;
@@ -1762,7 +1646,7 @@ static int __cil_cond_expr_to_sepol_expr(policydb_t *pdb, struct cil_list *cil_e
 	return SEPOL_OK;
 }
 
-int cil_booleanif_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_tree_node *node, struct cil_list *neverallows, hashtab_t filename_trans_table)
+int cil_booleanif_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_tree_node *node, hashtab_t filename_trans_table)
 {
 	int rc = SEPOL_ERR;
 	struct cil_args_booleanif bool_args;
@@ -1837,7 +1721,6 @@ int cil_booleanif_to_policydb(policydb_t *pdb, const struct cil_db *db, struct c
 	bool_args.db = db;
 	bool_args.pdb = pdb;
 	bool_args.cond_node = cond_node;
-	bool_args.neverallows = neverallows;
 	bool_args.filename_trans_table = filename_trans_table;
 
 	if (true_node != NULL) {
@@ -3202,17 +3085,9 @@ int __cil_node_to_policydb(struct cil_tree_node *node, void *extra_args)
 			break;
 		case CIL_AVRULE: {
 			struct cil_avrule *rule = node->data;
-			struct cil_list *neverallows = args->neverallows;
-			if (rule->rule_kind == CIL_AVRULE_NEVERALLOW) {
-				struct cil_neverallow *new_rule = NULL;
-
-				new_rule = cil_malloc(sizeof(*new_rule));
-				cil_list_init(&new_rule->rules, CIL_LIST_ITEM);
-				new_rule->node = node;
-
-				cil_list_prepend(neverallows, CIL_LIST_ITEM, new_rule);
-
-				rc = cil_avrule_to_policydb(pdb, db, node->data, neverallows);
+			if (db->disable_neverallow != CIL_TRUE && rule->rule_kind == CIL_AVRULE_NEVERALLOW) {
+				struct cil_list *neverallows = args->neverallows;
+				cil_list_prepend(neverallows, CIL_LIST_ITEM, node);
 			}
 			break;
 		}
@@ -3261,12 +3136,12 @@ int __cil_node_to_policydb(struct cil_tree_node *node, void *extra_args)
 	case 3:
 		switch (node->flavor) {
 		case CIL_BOOLEANIF:
-			rc = cil_booleanif_to_policydb(pdb, db, node, args->neverallows, filename_trans_table);
+			rc = cil_booleanif_to_policydb(pdb, db, node, filename_trans_table);
 			break;
 		case CIL_AVRULE: {
 				struct cil_avrule *rule = node->data;
 				if (rule->rule_kind != CIL_AVRULE_NEVERALLOW) {
-					rc = cil_avrule_to_policydb(pdb, db, node->data, args->neverallows);
+					rc = cil_avrule_to_policydb(pdb, db, node->data);
 				}
 			}
 			break;
@@ -3728,6 +3603,282 @@ exit:
 	return rc;
 }
 
+static void __cil_destroy_sepol_class_perms(class_perm_node_t *curr)
+{
+	class_perm_node_t *next;
+
+	while (curr) {
+		next = curr->next;
+		free(curr);
+		curr = next;
+	}
+}
+
+static int __cil_rule_to_sepol_class_perms(policydb_t *pdb, struct cil_list *classperms, class_perm_node_t **sepol_class_perms)
+{
+	int rc = SEPOL_ERR;
+	struct cil_list_item *i;
+	cil_list_for_each(i, classperms) {
+		if (i->flavor == CIL_CLASSPERMS) {
+			struct cil_classperms *cp = i->data;
+			if (FLAVOR(cp->class) == CIL_CLASS) {
+				class_perm_node_t *cpn = NULL;
+				class_datum_t *sepol_class = NULL;
+				uint32_t data = 0;
+
+				rc = __cil_get_sepol_class_datum(pdb, DATUM(cp->class), &sepol_class);
+				if (rc != SEPOL_OK) goto exit;
+
+				rc = __cil_perms_to_datum(cp->perms, sepol_class, &data);
+				if (rc != SEPOL_OK) goto exit;
+				if (data == 0) {
+					/* No permissions */
+					return SEPOL_OK;
+				}
+				cpn = cil_malloc(sizeof(class_perm_node_t));
+				cpn->tclass = sepol_class->s.value;
+				cpn->data = data;
+				cpn->next = *sepol_class_perms;
+				*sepol_class_perms = cpn;
+			} else { /* MAP */
+				struct cil_list_item *j = NULL;
+				cil_list_for_each(j, cp->perms) {
+					struct cil_perm *cmp = j->data;
+					rc = __cil_rule_to_sepol_class_perms(pdb, cmp->classperms, sepol_class_perms);
+					if (rc != SEPOL_OK) {
+						goto exit;
+					}
+				}
+			}
+		} else { /* SET */
+			struct cil_classperms_set *cp_set = i->data;
+			struct cil_classpermission *cp = cp_set->set;
+			rc = __cil_rule_to_sepol_class_perms(pdb, cp->classperms, sepol_class_perms);
+			if (rc != SEPOL_OK) {
+				goto exit;
+			}
+		}
+	}
+	return SEPOL_OK;
+
+exit:
+	return rc;
+}
+
+static void __cil_init_sepol_type_set(type_set_t *t)
+{
+	ebitmap_init(&t->types);
+	ebitmap_init(&t->negset);
+	t->flags = 0;
+}
+
+static int __cil_add_sepol_type(policydb_t *pdb, const struct cil_db *db, struct cil_symtab_datum *datum, ebitmap_t *map)
+{
+	int rc = SEPOL_ERR;
+	struct cil_tree_node *n = datum->nodes->head->data;
+	type_datum_t *sepol_datum = NULL;
+
+	if (n->flavor == CIL_TYPEATTRIBUTE) {
+		ebitmap_node_t *tnode;
+		unsigned int i;
+		struct cil_typeattribute *attr = (struct cil_typeattribute *)datum;
+		ebitmap_for_each_bit(attr->types, tnode, i) {
+			if (!ebitmap_get_bit(attr->types, i)) continue;
+			datum = DATUM(db->val_to_type[i]);
+			rc = __cil_get_sepol_type_datum(pdb, datum, &sepol_datum);
+			if (rc != SEPOL_OK) goto exit;
+			ebitmap_set_bit(map, sepol_datum->s.value - 1, 1);
+		}
+	} else {
+		rc = __cil_get_sepol_type_datum(pdb, datum, &sepol_datum);
+		if (rc != SEPOL_OK) goto exit;
+		ebitmap_set_bit(map, sepol_datum->s.value - 1, 1);
+	}
+
+	return SEPOL_OK;
+
+exit:
+	return rc;
+}
+
+static avrule_t *__cil_init_sepol_avrule(uint32_t kind, struct cil_tree_node *node)
+{
+	avrule_t *avrule;
+
+	avrule = cil_malloc(sizeof(avrule_t));
+	avrule->specified = kind;
+	avrule->flags = 0;
+	__cil_init_sepol_type_set(&avrule->stypes);
+	__cil_init_sepol_type_set(&avrule->ttypes);
+	avrule->perms = NULL;
+	avrule->line = node->line;
+	avrule->source_filename = node->path;
+	avrule->source_line = node->line;
+	avrule->next = NULL;
+	return avrule;
+}
+
+static void __cil_destroy_sepol_avrules(avrule_t *curr)
+{
+	avrule_t *next;
+
+	while (curr) {
+		next = curr->next;
+		ebitmap_destroy(&curr->stypes.types);
+		ebitmap_destroy(&curr->stypes.negset);
+		ebitmap_destroy(&curr->ttypes.types);
+		ebitmap_destroy(&curr->ttypes.negset);
+		__cil_destroy_sepol_class_perms(curr->perms);
+		free(curr);
+		curr = next;
+	}
+}
+
+static int __cil_rule_to_expanded_sepol_avrule(const struct cil_db *db, policydb_t *pdb, struct cil_tree_node *node, avrule_t **avrule)
+{
+	int rc = SEPOL_ERR;
+	struct cil_avrule *cil_rule = node->data;
+	struct cil_symtab_datum *tgt = cil_rule->tgt;
+	uint32_t kind;
+	avrule_t *rule;
+
+	*avrule = NULL;
+
+	switch (cil_rule->rule_kind) {
+	case CIL_AVRULE_AUDITALLOW:
+		kind = AVRULE_AUDITALLOW;
+		break;
+	case CIL_AVRULE_DONTAUDIT:
+		kind = AVRULE_AUDITDENY;
+		break;
+	case CIL_AVRULE_NEVERALLOW:
+		kind = AVRULE_NEVERALLOW;
+		break;
+	default:
+		kind = AVRULE_ALLOWED;
+		break;
+	}
+
+	rule = __cil_init_sepol_avrule(kind, node);
+
+	rc = __cil_rule_to_sepol_class_perms(pdb, cil_rule->classperms, &rule->perms);
+	if (rc != SEPOL_OK) {
+		goto exit;
+	}
+
+	rc = __cil_add_sepol_type(pdb, db, cil_rule->src, &rule->stypes.types);
+	if (rc != SEPOL_OK) {
+		goto exit;
+	}
+
+	if (tgt->fqn == CIL_KEY_SELF) {
+		rule->flags = RULE_SELF;
+	} else {
+		rc = __cil_add_sepol_type(pdb, db, cil_rule->tgt, &rule->ttypes.types);
+		if (rc != SEPOL_OK) {
+			goto exit;
+		}
+	}
+
+	rule->next = NULL;
+	*avrule = rule;
+
+	return SEPOL_OK;
+
+exit:
+	__cil_destroy_sepol_avrules(rule);
+	return rc;
+}
+
+static void __cil_print_parents(const char *pad, struct cil_tree_node *n)
+{
+	if (!n) return;
+
+	__cil_print_parents(pad, n->parent);
+
+	if (!n->path) {
+		cil_log(CIL_ERR,"%s%s\n", pad, cil_node_to_string(n));
+	} else {
+		cil_log(CIL_ERR,"%s%s at line %d of %s\n", pad, cil_node_to_string(n), n->line, n->path);
+	}
+}
+
+static void __cil_print_rule(const char *pad, const char *kind, struct cil_avrule *avrule)
+{
+	struct cil_list *cp_list = avrule->classperms;
+	struct cil_list_item *i1, *i2;
+
+	cil_log(CIL_ERR,"%s(%s ", pad, kind);
+	cil_log(CIL_ERR,"%s %s ", DATUM(avrule->src)->fqn, DATUM(avrule->tgt)->fqn);
+
+	i1 = cp_list->head;
+	if (i1->flavor == CIL_CLASSPERMS) {
+		struct cil_classperms *cp = i1->data;
+		cil_log(CIL_ERR,"(%s (", DATUM(cp->class)->fqn);
+		cil_list_for_each(i2, cp->perms) {
+			cil_log(CIL_ERR,"%s",DATUM(i2->data)->fqn);
+			if (i2 != cp->perms->tail) {
+				cil_log(CIL_ERR," ");
+			} else {
+				cil_log(CIL_ERR,"))");
+			}
+		}
+	} else {
+		struct cil_classperms_set *cp_set = i1->data;
+		cil_log(CIL_ERR,"%s", DATUM(cp_set->set)->fqn);
+	}
+
+	cil_log(CIL_ERR,")\n");
+}
+
+static int cil_check_neverallows(const struct cil_db *db, policydb_t *pdb, struct cil_list *neverallows)
+{
+	int rc = SEPOL_OK;
+	struct cil_list_item *i1;
+
+	cil_list_for_each(i1, neverallows) {
+		struct cil_tree_node *node = i1->data;
+		avrule_t *avrule;
+		rc = __cil_rule_to_expanded_sepol_avrule(db, pdb, node, &avrule);
+		if (rc != SEPOL_OK) {
+			cil_log(CIL_ERR, "Failed to create expanded sepol avrules to check neverallow rules\n");
+			goto exit;
+		}
+
+		rc = check_assertion(pdb, avrule);
+
+		if (rc == CIL_TRUE) {
+			struct cil_list_item *i2;
+			struct cil_list *matching;
+			struct cil_avrule *cil_rule = node->data;
+			struct cil_avrule target;
+			struct cil_tree_node *n2;
+			struct cil_avrule *r2;
+			target.rule_kind = CIL_AVRULE_ALLOWED;
+			target.src = cil_rule->src;
+			target.tgt = cil_rule->tgt;
+			target.classperms = cil_rule->classperms;
+			cil_log(CIL_ERR, "Neverallow check failed at line %d of %s\n", node->line, node->path);
+			__cil_print_rule("  ", "neverallow", cil_rule);
+			cil_list_init(&matching, CIL_NODE);
+			cil_find_matching_avrule_in_ast(db->ast->root, CIL_AVRULE, &target, matching, CIL_FALSE);
+			cil_list_for_each(i2, matching) {
+				n2 = i2->data;
+				r2 = n2->data;
+				__cil_print_parents("    ", n2);
+				__cil_print_rule("      ", "allow", r2);
+			}
+			cil_log(CIL_ERR,"\n");
+			cil_list_destroy(&matching, CIL_FALSE);
+		}
+		__cil_destroy_sepol_avrules(avrule);
+		avrule = NULL;
+	}
+
+exit:
+	return rc;
+}
+
 // assumes policydb is already allocated and initialized properly with things
 // like policy type set to kernel and version set appropriately
 int cil_binary_create_allocated_pdb(const struct cil_db *db, sepol_policydb_t *policydb)
@@ -3822,13 +3973,19 @@ int cil_binary_create_allocated_pdb(const struct cil_db *db, sepol_policydb_t *p
 	cond_optimize_lists(pdb->cond_list);
 	__cil_set_conditional_state_and_flags(pdb);
 
+	if (db->disable_neverallow != CIL_TRUE) {
+		cil_log(CIL_INFO, "Checking Neverallows\n");
+		rc = cil_check_neverallows(db, pdb, neverallows);
+		if (rc != SEPOL_OK) goto exit;
+	}
+
 	rc = SEPOL_OK;
 
 exit:
 	hashtab_destroy(filename_trans_table);
 	hashtab_destroy(range_trans_table);
 	hashtab_destroy(role_trans_table);
-	cil_neverallows_list_destroy(neverallows);
+	cil_list_destroy(&neverallows, CIL_FALSE);
 
 	return rc;
 }
diff --git a/libsepol/cil/src/cil_binary.h b/libsepol/cil/src/cil_binary.h
index 5045c6e..72c0f95 100644
--- a/libsepol/cil/src/cil_binary.h
+++ b/libsepol/cil/src/cil_binary.h
@@ -250,7 +250,7 @@ int cil_type_rule_to_policydb(policydb_t *pdb, const struct cil_db *db, struct c
  *
  * @return SEPOL_OK upon success or an error otherwise.
  */
-int cil_avrule_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_avrule *cil_avrule, struct cil_list *neverallows);
+int cil_avrule_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_avrule *cil_avrule);
 
 /**
  * Insert cil booleanif structure into sepol policydb.  This populates the
@@ -262,7 +262,7 @@ int cil_avrule_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_
  *
  * @return SEPOL_OK upon success or an error otherwise.
  */
-int cil_booleanif_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_tree_node *node, struct cil_list *neverallows, hashtab_t filename_trans_table);
+int cil_booleanif_to_policydb(policydb_t *pdb, const struct cil_db *db, struct cil_tree_node *node, hashtab_t filename_trans_table);
 
 /**
  * Insert cil role transition structure into sepol policydb.
-- 
1.9.3

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