framer-802154: Support for creating and parsing frames with security headers

core/net/mac/frame802154.c

@@ -122,7 +122,8 @@ field_len(frame802154_t *p, field_length_t *flen)
 
   /* Aux security header */
   if(p->fcf.security_enabled & 1) {
-    /* TODO Aux security header not yet implemented */
+    flen->aux_sec_len = 5;
+    /* TODO Support key identifier mode !=0 */
 #if 0
     switch(p->aux_hdr.security_control.key_id_mode) {
     case 0:
@@ -232,8 +233,10 @@ frame802154_create(frame802154_t *p, uint8_t *buf, int buf_len)
 
   /* Aux header */
   if(flen.aux_sec_len) {
-    /* TODO Aux security header not yet implemented */
+    /* TODO Support key identifier mode !=0 */
-/*     pos += flen.aux_sec_len; */
+    tx_frame_buffer[pos++] = p->aux_hdr.security_control.security_level;
+    memcpy(tx_frame_buffer + pos, p->aux_hdr.frame_counter.u8, 4);
+    pos += 4;
   }
 
   return (int)pos;
@@ -338,8 +341,17 @@ frame802154_parse(uint8_t *data, int len, frame802154_t *pf)
   }
 
   if(fcf.security_enabled) {
-    /* TODO aux security header, not yet implemented */
+    pf->aux_hdr.security_control.security_level = p[0] & 7;
-/*     return 0; */
+    pf->aux_hdr.security_control.key_id_mode = (p[0] >> 3) & 3;
+    p += 1;
+    
+    memcpy(pf->aux_hdr.frame_counter.u8, p, 4);
+    p += 4;
+        
+    if(pf->aux_hdr.security_control.key_id_mode) {
+      /* TODO Support key identifier mode !=0 */
+      return 0;
+    }
   }
 
   /* header length */

core/net/mac/frame802154.h

@@ -140,10 +140,16 @@ typedef struct {
   uint8_t  reserved;       /**< 3 bit. Reserved bits       */
 } frame802154_scf_t;
 
+typedef union {
+  uint32_t u32;
+  uint16_t u16[2];
+  uint8_t u8[4];
+} frame802154_frame_counter_t;
+
 /** \brief 802.15.4 Aux security header */
 typedef struct {
   frame802154_scf_t security_control;  /**< Security control bitfield */
-  uint32_t frame_counter;   /**< Frame counter, used for security */
+  frame802154_frame_counter_t frame_counter;   /**< Frame counter, used for security */
   uint8_t  key[9];          /**< The key itself, or an index to the key */
 } frame802154_aux_hdr_t;
 

core/net/mac/framer-802154.c

@@ -102,7 +102,9 @@ create_frame(int type, int do_create)
 
   /* Build the FCF. */
   params.fcf.frame_type = FRAME802154_DATAFRAME;
-  params.fcf.security_enabled = 0;
+  if(packetbuf_attr(PACKETBUF_ATTR_SECURITY_LEVEL)) {
+    params.fcf.security_enabled = 1;
+  }
   params.fcf.frame_pending = packetbuf_attr(PACKETBUF_ATTR_PENDING);
   if(linkaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &linkaddr_null)) {
     params.fcf.ack_required = 0;
@@ -111,8 +113,13 @@ create_frame(int type, int do_create)
   }
   params.fcf.panid_compression = 0;
 
-  /* Insert IEEE 802.15.4 (2003) version bit. */
+  /* Insert IEEE 802.15.4 (2006) version bits. */
-  params.fcf.frame_version = FRAME802154_IEEE802154_2003;
+  params.fcf.frame_version = FRAME802154_IEEE802154_2006;
+  
+  /* Setting security-related attributes */
+  params.aux_hdr.security_control.security_level = packetbuf_attr(PACKETBUF_ATTR_SECURITY_LEVEL);
+  params.aux_hdr.frame_counter.u16[0] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1);
+  params.aux_hdr.frame_counter.u16[1] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3);
 
   /* Increment and set the data sequence number. */
   if(!do_create) {
@@ -228,6 +235,11 @@ parse(void)
     /*    packetbuf_set_attr(PACKETBUF_ATTR_RELIABLE, frame.fcf.ack_required);*/
     packetbuf_set_attr(PACKETBUF_ATTR_PACKET_ID, frame.seq);
     
+    /* Setting security-related attributes */
+    packetbuf_set_attr(PACKETBUF_ATTR_SECURITY_LEVEL, frame.aux_hdr.security_control.security_level);
+    packetbuf_set_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1, frame.aux_hdr.frame_counter.u16[0]);
+    packetbuf_set_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3, frame.aux_hdr.frame_counter.u16[1]);
+
     PRINTF("15.4-IN: %2X", frame.fcf.frame_type);
     PRINTADDR(packetbuf_addr(PACKETBUF_ADDR_SENDER));
     PRINTADDR(packetbuf_addr(PACKETBUF_ADDR_RECEIVER));

core/net/packetbuf.h

@@ -356,6 +356,9 @@ enum {
   PACKETBUF_ATTR_MAX_REXMIT,
   PACKETBUF_ATTR_NUM_REXMIT,
   PACKETBUF_ATTR_PENDING,
+  PACKETBUF_ATTR_SECURITY_LEVEL,
+  PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1,
+  PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3,
   
   /* Scope 2 attributes: used between end-to-end nodes. */
   PACKETBUF_ATTR_HOPS,