Introduce "features" for the kernel backends returning kernel capabilities

1 files changed, 19 insertions, 0 deletions

diff --git a/src/libhydra/kernel/kernel_interface.h b/src/libhydra/kernel/kernel_interface.h
index 8d8ef2e83..8d8d048d0 100644
--- a/src/libhydra/kernel/kernel_interface.h
+++ b/src/libhydra/kernel/kernel_interface.h
@@ -47,6 +47,7 @@
 #define KERNEL_INTERFACE_H_
 
 typedef struct kernel_interface_t kernel_interface_t;
+typedef enum kernel_feature_t kernel_feature_t;
 
 #include <networking/host.h>
 #include <crypto/prf_plus.h>
@@ -56,6 +57,17 @@ typedef struct kernel_interface_t kernel_interface_t;
 #include <kernel/kernel_net.h>
 
 /**
+ * Bitfield of optional features a kernel backend supports.
+ *
+ * This feature-set is for both, kernel_ipsec_t and kernel_net_t. Each
+ * backend returns a subset of these features.
+ */
+enum kernel_feature_t {
+	/** IPsec can process ESPv3 (RFC 4303) TFC padded packets */
+	KERNEL_ESP_V3_TFC = (1<<0),
+};
+
+/**
  * Constructor function for ipsec kernel interface
  */
 typedef kernel_ipsec_t* (*kernel_ipsec_constructor_t)(void);
@@ -74,6 +86,13 @@ typedef kernel_net_t* (*kernel_net_constructor_t)(void);
 struct kernel_interface_t {
 
 	/**
+	 * Get the feature set supported by the net and ipsec kernel backends.
+	 *
+	 * @return				ORed feature-set of backends
+	 */
+	kernel_feature_t (*get_features)(kernel_interface_t *this);
+
+	/**
 	 * Get a SPI from the kernel.
 	 *
 	 * @param src		source address of SA