From b6978b30e8ddb659502d14f8802ec1a03651b018 Mon Sep 17 00:00:00 2001
From: George Oikonomou <antzougias@gmail.com>
Date: Sat, 8 Mar 2014 21:24:50 +0000
Subject: [PATCH] Declare and Implement generic ICMPv6 handler management

---
 core/net/ipv6/uip-icmp6.c | 43 ++++++++++++++++++++++++++++++++
 core/net/ipv6/uip-icmp6.h | 52 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 95 insertions(+)

diff --git a/core/net/ipv6/uip-icmp6.c b/core/net/ipv6/uip-icmp6.c
index 1ad0c62fc..e788b6d7f 100644
--- a/core/net/ipv6/uip-icmp6.c
+++ b/core/net/ipv6/uip-icmp6.c
@@ -74,7 +74,50 @@
 static uip_ipaddr_t tmp_ipaddr;
 
 LIST(echo_reply_callback_list);
+/*---------------------------------------------------------------------------*/
+/* List of input handlers */
+LIST(input_handler_list);
+/*---------------------------------------------------------------------------*/
+static uip_icmp6_input_handler_t *
+input_handler_lookup(uint8_t type, uint8_t icode)
+{
+  uip_icmp6_input_handler_t *handler = NULL;
 
+  for(handler = list_head(input_handler_list);
+      handler != NULL;
+      handler = list_item_next(handler)) {
+    if(handler->type == type &&
+       (handler->icode == icode ||
+        handler->icode == UIP_ICMP6_HANDLER_CODE_ANY)) {
+      return handler;
+    }
+  }
+
+  return NULL;
+}
+/*---------------------------------------------------------------------------*/
+uint8_t
+uip_icmp6_input(uint8_t type, uint8_t icode)
+{
+  uip_icmp6_input_handler_t *handler = input_handler_lookup(type, icode);
+
+  if(handler == NULL) {
+    return UIP_ICMP6_INPUT_ERROR;
+  }
+
+  if(handler->handler == NULL) {
+    return UIP_ICMP6_INPUT_ERROR;
+  }
+
+  handler->handler();
+  return UIP_ICMP6_INPUT_SUCCESS;
+}
+/*---------------------------------------------------------------------------*/
+void
+uip_icmp6_register_input_handler(uip_icmp6_input_handler_t *handler)
+{
+  list_add(input_handler_list, handler);
+}
 /*---------------------------------------------------------------------------*/
 void
 uip_icmp6_echo_request_input(void)
diff --git a/core/net/ipv6/uip-icmp6.h b/core/net/ipv6/uip-icmp6.h
index fd5f7136f..842ae3670 100644
--- a/core/net/ipv6/uip-icmp6.h
+++ b/core/net/ipv6/uip-icmp6.h
@@ -192,8 +192,60 @@ uip_icmp6_echo_reply_callback_add(struct uip_icmp6_echo_reply_notification *n,
 void
 uip_icmp6_echo_reply_callback_rm(struct uip_icmp6_echo_reply_notification *n);
 
+/* Generic ICMPv6 input handers */
+typedef struct uip_icmp6_input_handler {
+  struct uip_icmp6_input_handler *next;
+  uint8_t type;
+  uint8_t icode;
+  void (*handler)(void);
+} uip_icmp6_input_handler_t;
 
+#define UIP_ICMP6_INPUT_SUCCESS     0
+#define UIP_ICMP6_INPUT_ERROR       1
 
+#define UIP_ICMP6_HANDLER_CODE_ANY 0xFF /* Handle all codes for this type */
+
+/*
+ * Initialise a variable of type uip_icmp6_input_handler, to be used later as
+ * the argument to uip_icmp6_register_input_handler
+ *
+ * The function pointer stored in this variable will get called and will be
+ * expected to handle incoming ICMPv6 datagrams of the specified type/code
+ *
+ * If code has a value of UIP_ICMP6_HANDLER_CODE_ANY, the same function
+ * will handle all codes for this type. In other words, the ICMPv6
+ * message's code is "don't care"
+ */
+#define UIP_ICMP6_HANDLER(name, type, code, func) \
+  static uip_icmp6_input_handler_t name = { NULL, type, code, func }
+
+/**
+ * \brief Handle an incoming ICMPv6 message
+ * \param type The ICMPv6 message type
+ * \param icode The ICMPv6 message code
+ * \return Success: UIP_ICMP6_INPUT_SUCCESS, Error: UIP_ICMP6_INPUT_ERROR
+ *
+ * Generic handler for unknown ICMPv6 types. It will lookup for a registered
+ * function capable of handing this message type. The function must have first
+ * been registered with uip_icmp6_register_input_handler. The function is in
+ * charge of setting uip_len to 0, otherwise the uIPv6 core will attempt to
+ * send whatever remains in the UIP_IP_BUF.
+ *
+ * A return value of UIP_ICMP6_INPUT_ERROR means that a handler could not be
+ * invoked. This is most likely because the ICMPv6 type does not have a valid
+ * handler associated with it.
+
+ * UIP_ICMP6_INPUT_SUCCESS signifies that a handler was found for this ICMPv6
+ * type and that it was invoked. It does NOT provide any indication whatsoever
+ * regarding whether the handler itself succeeded.
+ */
+uint8_t uip_icmp6_input(uint8_t type, uint8_t icode);
+
+/**
+ * \brief Register a handler which can handle a specific ICMPv6 message type
+ * \param handler A pointer to the handler
+ */
+void uip_icmp6_register_input_handler(uip_icmp6_input_handler_t *handler);
 
 /** @} */