From dadf1e9ad66318fdd814cf06af2b83741467a3d8 Mon Sep 17 00:00:00 2001

From: James Carter <jwcart2@gmail.com>

Date: Tue, 30 Mar 2021 13:39:17 -0400

Subject: [PATCH] libsepol/cil: Sync checks for invalid rules in booleanifs

When building the AST, typemember rules in a booleanif block will

be incorrectly called invalid. They are allowed in the kernel

policy and should be allowed in CIL.

When resolving the AST, if a neverallow rule is copied into a

booleanif block, it will not be considered an invalid rule, even

though this is not allowed in the kernel policy.

Update the booleanif checks to allow typemember rules and to not

allow neverallow rules in booleanifs. Also use the same form of

conditional for the checks when building and resolving the AST.

Signed-off-by: James Carter <jwcart2@gmail.com>

---

 libsepol/cil/src/cil_build_ast.c   |  3 ++-

 libsepol/cil/src/cil_resolve_ast.c | 23 +++++++++++++++--------

 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/libsepol/cil/src/cil_build_ast.c b/libsepol/cil/src/cil_build_ast.c

index ceb55324..3a91be03 100644

--- a/libsepol/cil/src/cil_build_ast.c

+++ b/libsepol/cil/src/cil_build_ast.c

@@ -6136,7 +6136,8 @@ int __cil_build_ast_node_helper(struct cil_tree_node *parse_current, uint32_t *f

 			parse_current->data != CIL_KEY_DONTAUDIT &&

 			parse_current->data != CIL_KEY_AUDITALLOW &&

 			parse_current->data != CIL_KEY_TYPETRANSITION &&

-			parse_current->data != CIL_KEY_TYPECHANGE) {

+			parse_current->data != CIL_KEY_TYPECHANGE &&

+			parse_current->data != CIL_KEY_TYPEMEMBER) {

 			rc = SEPOL_ERR;

 			cil_tree_log(parse_current, CIL_ERR, "Found %s", (char*)parse_current->data);

 			if (((struct cil_booleanif*)boolif->data)->preserved_tunable) {

diff --git a/libsepol/cil/src/cil_resolve_ast.c b/libsepol/cil/src/cil_resolve_ast.c

index c520c44a..06b6ab48 100644

--- a/libsepol/cil/src/cil_resolve_ast.c

+++ b/libsepol/cil/src/cil_resolve_ast.c

@@ -3689,7 +3689,7 @@ exit:

 int __cil_resolve_ast_node_helper(struct cil_tree_node *node, uint32_t *finished, void *extra_args)

 {

-	int rc = SEPOL_ERR;

+	int rc = SEPOL_OK;

 	struct cil_args_resolve *args = extra_args;

 	enum cil_pass pass = args->pass;

 	struct cil_tree_node *block = args->block;

@@ -3732,18 +3732,25 @@ int __cil_resolve_ast_node_helper(struct cil_tree_node *node, uint32_t *finished

 	}

 	if (boolif != NULL) {

-		if (!(node->flavor == CIL_TUNABLEIF ||

-		      node->flavor == CIL_CALL ||

-		      node->flavor == CIL_CONDBLOCK ||

-		      node->flavor == CIL_AVRULE ||

-		      node->flavor == CIL_TYPE_RULE ||

-		      node->flavor == CIL_NAMETYPETRANSITION)) {

+		if (node->flavor != CIL_TUNABLEIF &&

+			node->flavor != CIL_CALL &&

+			node->flavor != CIL_CONDBLOCK &&

+			node->flavor != CIL_AVRULE &&

+			node->flavor != CIL_TYPE_RULE &&

+			node->flavor != CIL_NAMETYPETRANSITION) {

+			rc = SEPOL_ERR;

+		} else if (node->flavor == CIL_AVRULE) {

+			struct cil_avrule *rule = node->data;

+			if (rule->rule_kind == CIL_AVRULE_NEVERALLOW) {

+				rc = SEPOL_ERR;

+			}

+		}

+		if (rc == SEPOL_ERR) {

 			if (((struct cil_booleanif*)boolif->data)->preserved_tunable) {

 				cil_tree_log(node, CIL_ERR, "%s statement is not allowed in booleanifs (tunableif treated as a booleanif)", cil_node_to_string(node));

 			} else {

 				cil_tree_log(node, CIL_ERR, "%s statement is not allowed in booleanifs", cil_node_to_string(node));

 			}

-			rc = SEPOL_ERR;

 			goto exit;

 		}

 	}

-- 

2.30.2