From 6486c51692fd31c480089af9a9993b47b8194f19 Mon Sep 17 00:00:00 2001
From: kkrentz <konrad.krentz@googlemail.com>
Date: Fri, 24 May 2013 05:24:14 -0700
Subject: [PATCH] CC2420: Hardware-accelerated aes_128_driver

---
 dev/cc2420/cc2420.c | 40 +++++++++++++++++++++++++++++++++++-----
 dev/cc2420/cc2420.h |  4 ++++
 2 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/dev/cc2420/cc2420.c b/dev/cc2420/cc2420.c
index bdc1c3140..a3a372ffd 100644
--- a/dev/cc2420/cc2420.c
+++ b/dev/cc2420/cc2420.c
@@ -352,6 +352,39 @@ wait_for_transmission(void)
       && RTIMER_CLOCK_LT(RTIMER_NOW(), t0 + (RTIMER_SECOND / 10)));
 }
 /*---------------------------------------------------------------------------*/
+static void
+init_security(void)
+{
+  /* only use key 0 */
+  setreg(CC2420_SECCTRL0, 0);
+  setreg(CC2420_SECCTRL1, 0);
+}
+/*---------------------------------------------------------------------------*/
+static void
+set_key(uint8_t *key)
+{
+  write_ram(key, CC2420RAM_KEY0, 16, CC2420_WRITE_RAM_REVERSE);
+}
+/*---------------------------------------------------------------------------*/
+static void
+encrypt(uint8_t *plaintext_and_result)
+{
+  write_ram(plaintext_and_result,
+      CC2420RAM_SABUF,
+      16,
+      CC2420_WRITE_RAM_IN_ORDER);
+  
+  strobe(CC2420_SAES);
+  while(get_status() & BV(CC2420_ENC_BUSY));
+  
+  read_ram(plaintext_and_result, CC2420RAM_SABUF, 16);
+}
+/*---------------------------------------------------------------------------*/
+const struct aes_128_driver cc2420_aes_128_driver = {
+  set_key,
+  encrypt
+};
+/*---------------------------------------------------------------------------*/
 static uint8_t locked, lock_on, lock_off;
 
 static void
@@ -473,10 +506,7 @@ cc2420_init(void)
   /* Set the FIFOP threshold to maximum. */
   setreg(CC2420_IOCFG0, FIFOP_THR(127));
 
-  /* Turn off "Security enable" (page 32). */
-  reg = getreg(CC2420_SECCTRL0);
-  reg &= ~RXFIFO_PROTECTION;
-  setreg(CC2420_SECCTRL0, reg);
+  init_security();
 
   cc2420_set_pan_addr(0xffff, 0x0000, NULL);
   cc2420_set_channel(CC2420_CONF_CHANNEL);
@@ -590,7 +620,7 @@ static int
 cc2420_prepare(const void *payload, unsigned short payload_len)
 {
   uint8_t total_len;
-
+  
   GET_LOCK();
 
   PRINTF("cc2420: sending %d bytes\n", payload_len);
diff --git a/dev/cc2420/cc2420.h b/dev/cc2420/cc2420.h
index 133db83c4..d840c7b9b 100644
--- a/dev/cc2420/cc2420.h
+++ b/dev/cc2420/cc2420.h
@@ -36,6 +36,7 @@
  * \author
  *         Adam Dunkels <adam@sics.se>
  *         Joakim Eriksson <joakime@sics.se>
+ *         Konrad Krentz <konrad.krentz@gmail.com>
  */
 
 #ifndef CC2420_H_
@@ -45,6 +46,7 @@
 #include "dev/spi.h"
 #include "dev/radio.h"
 #include "cc2420_const.h"
+#include "lib/aes-128.h"
 
 int cc2420_init(void);
 
@@ -88,6 +90,8 @@ int cc2420_off(void);
 
 void cc2420_set_cca_threshold(int value);
 
+extern const struct aes_128_driver cc2420_aes_128_driver;
+
 /************************************************************************/
 /* Additional SPI Macros for the CC2420 */
 /************************************************************************/