@@ -194,3 +194,39 @@ void ipe_audit_policy_load(const struct ipe_policy *const p)
 
 	audit_log_end(ab);
 }
+
+/**
+ * ipe_audit_enforce - Audit a change in IPE's enforcement state.
+ */
+void ipe_audit_enforce(void)
+{
+	struct audit_buffer *ab;
+
+	ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS);
+	if (!ab)
+		return;
+
+	audit_log_format(ab, "permissive=%d", !READ_ONCE(enforce));
+	audit_log_format(ab, " auid=%u ses=%u lsm=ipe res=1",
+			 from_kuid(&init_user_ns, audit_get_loginuid(current)),
+			 audit_get_sessionid(current));
+
+	audit_log_end(ab);
+}
+
+/**
+ * emit_enforcement - Emit the enforcement state of IPE started with.
+ *
+ * Return:
+ * 0 - Always
+ */
+static int emit_enforcement(void)
+{
+	if (!ipe_enabled)
+		return -EOPNOTSUPP;
+
+	ipe_audit_enforce();
+	return 0;
+}
+
+late_initcall(emit_enforcement);

@@ -14,5 +14,6 @@ void ipe_audit_match(const struct ipe_eval_ctx *const ctx,
 void ipe_audit_policy_load(const struct ipe_policy *const p);
 void ipe_audit_policy_activation(const struct ipe_policy *const op,
 				 const struct ipe_policy *const np);
+void ipe_audit_enforce(void);
 
 #endif /* IPE_AUDIT_H */

@@ -20,6 +20,7 @@
 
 struct ipe_policy __rcu *ipe_active_policy;
 bool success_audit;
+bool enforce = true;
 
 static struct super_block *pinned_sb;
 static DEFINE_SPINLOCK(pin_lock);

@@ -119,6 +120,7 @@ int ipe_evaluate_event(const struct ipe_eval_ctx *const ctx)
 {
 	int rc = 0;
 	bool match = false;
+	bool enforcing = true;
 	enum ipe_action_type action;
 	enum ipe_match match_type;
 	struct ipe_policy *pol = NULL;

@@ -133,6 +135,8 @@ int ipe_evaluate_event(const struct ipe_eval_ctx *const ctx)
 	if (!pol)
 		goto out;
 
+	enforcing = READ_ONCE(enforce);
+
 	if (ctx->op == ipe_op_max) {
 		action = pol->parsed->global_default_action;
 		match_type = ipe_match_global;

@@ -168,6 +172,9 @@ int ipe_evaluate_event(const struct ipe_eval_ctx *const ctx)
 	if (action == ipe_action_deny)
 		rc = -EACCES;
 
+	if (!enforcing)
+		rc = 0;
+
 out:
 	return rc;
 }

@@ -198,3 +205,5 @@ void ipe_invalidate_pinned_sb(const struct super_block *mnt_sb)
 
 module_param(success_audit, bool, 0400);
 MODULE_PARM_DESC(success_audit, "Start IPE with success auditing enabled");
+module_param(enforce, bool, 0400);
+MODULE_PARM_DESC(enforce, "Start IPE in enforce or permissive mode");

@@ -14,6 +14,7 @@
 
 extern struct ipe_policy __rcu *ipe_active_policy;
 extern bool success_audit;
+extern bool enforce;
 
 struct ipe_eval_ctx {
 	enum ipe_op_type op;

@@ -15,6 +15,7 @@ static struct dentry *np __ro_after_init;
 static struct dentry *root __ro_after_init;
 struct dentry *policy_root __ro_after_init;
 static struct dentry *audit_node __ro_after_init;
+static struct dentry *enforce_node __ro_after_init;
 
 /**
  * setaudit - Write handler for the securityfs node, "ipe/success_audit"

@@ -48,8 +49,8 @@ static ssize_t setaudit(struct file *f, const char __user *data,
 /**
  * getaudit - Read handler for the securityfs node, "ipe/success_audit"
  * @f: Supplies a file structure representing the securityfs node.
- * @data: Supplies a buffer passed to the read syscall
- * @len: Supplies the length of @data
+ * @data: Supplies a buffer passed to the read syscall.
+ * @len: Supplies the length of @data.
  * @offset: unused.
  *
  * Return:

@@ -66,6 +67,57 @@ static ssize_t getaudit(struct file *f, char __user *data,
 	return simple_read_from_buffer(data, len, offset, result, 1);
 }
 
+/**
+ * setenforce - Write handler for the securityfs node, "ipe/enforce"
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * Return:
+ * * >0	- Success, Length of buffer written
+ * * <0	- Error
+ */
+static ssize_t setenforce(struct file *f, const char __user *data,
+			  size_t len, loff_t *offset)
+{
+	int rc = 0;
+	bool value;
+
+	if (!file_ns_capable(f, &init_user_ns, CAP_MAC_ADMIN))
+		return -EPERM;
+
+	rc = kstrtobool_from_user(data, len, &value);
+	if (rc)
+		return rc;
+
+	WRITE_ONCE(enforce, value);
+	ipe_audit_enforce();
+
+	return len;
+}
+
+/**
+ * getenforce - Read handler for the securityfs node, "ipe/enforce"
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the read syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * Return:
+ * * >0	- Success, Length of buffer written
+ * * <0	- Error
+ */
+static ssize_t getenforce(struct file *f, char __user *data,
+			  size_t len, loff_t *offset)
+{
+	const char *result;
+
+	result = ((READ_ONCE(enforce)) ? "1" : "0");
+
+	return simple_read_from_buffer(data, len, offset, result, 1);
+}
+
 /**
  * new_policy - Write handler for the securityfs node, "ipe/new_policy".
  * @f: Supplies a file structure representing the securityfs node.

@@ -118,6 +170,11 @@ static const struct file_operations audit_fops = {
 	.read = getaudit,
 };
 
+static const struct file_operations enforce_fops = {
+	.write = setenforce,
+	.read = getenforce,
+};
+
 /**
  * ipe_init_securityfs - Initialize IPE's securityfs tree at fsinit.
  *

@@ -151,6 +208,13 @@ static int __init ipe_init_securityfs(void)
 		goto err;
 	}
 
+	enforce_node = securityfs_create_file("enforce", 0600, root, NULL,
+					      &enforce_fops);
+	if (IS_ERR(enforce_node)) {
+		rc = PTR_ERR(enforce_node);
+		goto err;
+	}
+
 	policy_root = securityfs_create_dir("policies", root);
 	if (IS_ERR(policy_root)) {
 		rc = PTR_ERR(policy_root);

@@ -162,6 +226,7 @@ static int __init ipe_init_securityfs(void)
 	securityfs_remove(np);
 	securityfs_remove(root);
 	securityfs_remove(audit_node);
+	securityfs_remove(enforce_node);
 	securityfs_remove(policy_root);
 	return rc;
 }