From c0a693672c7333b35f97753eb078a746c3fd5b5e Mon Sep 17 00:00:00 2001
From: Robert Quattlebaum <darco@deepdarc.com>
Date: Mon, 21 Mar 2011 14:25:55 -0700
Subject: [PATCH] core/net: Added support for "bridge mode".

"Bridge mode" allows devices to more easily send 802.15.4 packets as if
they were a different device. It also turns off any packet filtering
that may be implemented at layer 2. It works by allowing
`PACKETBUF_ADDR_SENDER` to be set earlier in the stack.

This is useful for implementing 6LoWPAN-ethernet bridges.

Enabled via setting `NETSTACK_CONF_BRIDGE_MODE` to 1. Disabled by
default.
---
 core/net/mac/contikimac.c | 3 +++
 core/net/mac/cxmac.c      | 3 +++
 core/net/mac/sicslowmac.c | 6 ++++++
 core/net/sicslowpan.c     | 5 +++++
 4 files changed, 17 insertions(+)

diff --git a/core/net/mac/contikimac.c b/core/net/mac/contikimac.c
index 06998c42c..0487d8b8e 100644
--- a/core/net/mac/contikimac.c
+++ b/core/net/mac/contikimac.c
@@ -549,7 +549,10 @@ send_packet(mac_callback_t mac_callback, void *mac_callback_ptr, struct rdc_buf_
     return MAC_TX_ERR_FATAL;
   }
 
+#if !NETSTACK_CONF_BRIDGE_MODE
+  /* If NETSTACK_CONF_BRIDGE_MODE is set, assume PACKETBUF_ADDR_SENDER is already set. */
   packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &rimeaddr_node_addr);
+#endif
   if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) {
     is_broadcast = 1;
     PRINTDEBUG("contikimac: send broadcast\n");
diff --git a/core/net/mac/cxmac.c b/core/net/mac/cxmac.c
index daac9e020..1c7bbaf9a 100644
--- a/core/net/mac/cxmac.c
+++ b/core/net/mac/cxmac.c
@@ -429,7 +429,10 @@ send_packet(void)
 
 
   /* Create the X-MAC header for the data packet. */
+#if !NETSTACK_CONF_BRIDGE_MODE
+  /* If NETSTACK_CONF_BRIDGE_MODE is set, assume PACKETBUF_ADDR_SENDER is already set. */
   packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &rimeaddr_node_addr);
+#endif
   if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) {
     is_broadcast = 1;
     PRINTDEBUG("cxmac: send broadcast\n");
diff --git a/core/net/mac/sicslowmac.c b/core/net/mac/sicslowmac.c
index b77cd86b3..a9a7e60f0 100644
--- a/core/net/mac/sicslowmac.c
+++ b/core/net/mac/sicslowmac.c
@@ -146,7 +146,11 @@ send_packet(mac_callback_t sent, void *ptr)
    * Set up the source address using only the long address mode for
    * phase 1.
    */
+#if NETSTACK_CONF_BRIDGE_MODE
+  rimeaddr_copy((rimeaddr_t *)&params.src_addr,packetbuf_addr(PACKETBUF_ADDR_SENDER));
+#else
   rimeaddr_copy((rimeaddr_t *)&params.src_addr, &rimeaddr_node_addr);
+#endif
 
   params.payload = packetbuf_dataptr();
   params.payload_len = packetbuf_datalen();
@@ -203,12 +207,14 @@ input_packet(void)
       }
       if(!is_broadcast_addr(frame.fcf.dest_addr_mode, frame.dest_addr)) {
         packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, (rimeaddr_t *)&frame.dest_addr);
+#if !NETSTACK_CONF_BRIDGE_MODE
         if(!rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
                          &rimeaddr_node_addr)) {
           /* Not for this node */
           PRINTF("6MAC: not for us\n");
           return;
         }
+#endif
       }
     }
     packetbuf_set_addr(PACKETBUF_ADDR_SENDER, (rimeaddr_t *)&frame.src_addr);
diff --git a/core/net/sicslowpan.c b/core/net/sicslowpan.c
index 2bb94574f..74edcf993 100644
--- a/core/net/sicslowpan.c
+++ b/core/net/sicslowpan.c
@@ -1329,6 +1329,11 @@ send_packet(rimeaddr_t *dest)
    */
   packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, dest);
 
+#if NETSTACK_CONF_BRIDGE_MODE
+  /* This needs to be explicitly set here for bridge mode to work */
+  packetbuf_set_addr(PACKETBUF_ADDR_SENDER,(void*)&uip_lladdr);
+#endif
+
   /* Force acknowledge from sender (test hardware autoacks) */
 #if SICSLOWPAN_CONF_ACK_ALL
     packetbuf_set_attr(PACKETBUF_ATTR_RELIABLE, 1);