Set the Key Source field for 802.15.4 Key ID Mode 2. (#821)

src/core/mac/mac.cpp

@@ -647,11 +647,15 @@ void Mac::ProcessTransmitSecurity(Frame &aFrame)
         break;
 
     case Frame::kKeyIdMode2:
+    {
+        const uint8_t keySource[] = {0xff, 0xff, 0xff, 0xff};
         key = sMode2Key;
         frameCounter = 0xffffffff;
+        aFrame.SetKeySource(keySource);
         aFrame.SetKeyId(0xff);
         extAddress = static_cast<const ExtAddress *>(&sMode2ExtAddress);
         break;
+    }
 
     default:
         assert(false);

src/core/mac/mac_frame.cpp

@@ -111,25 +111,25 @@ ThreadError Frame::InitMacHeader(uint16_t aFcf, uint8_t aSecurityControl)
 
         if (aSecurityControl & kSecLevelMask)
         {
-            length += 5;
+            length += kSecurityControlSize + kFrameCounterSize;
         }
 
         switch (aSecurityControl & kKeyIdModeMask)
         {
         case kKeyIdMode0:
-            length += kKeyIdLengthMode0;
+            length += kKeySourceSizeMode0;
             break;
 
         case kKeyIdMode1:
-            length += kKeyIdLengthMode1;
+            length += kKeySourceSizeMode1 + kKeyIndexSize;
             break;
 
         case kKeyIdMode2:
-            length += kKeyIdLengthMode2;
+            length += kKeySourceSizeMode2 + kKeyIndexSize;
             break;
 
         case kKeyIdMode3:
-            length += kKeyIdLengthMode3;
+            length += kKeySourceSizeMode3 + kKeyIndexSize;
             break;
         }
     }
@@ -606,15 +606,71 @@ ThreadError Frame::SetFrameCounter(uint32_t aFrameCounter)
     return kThreadError_None;
 }
 
+const uint8_t *Frame::GetKeySource(void)
+{
+    uint8_t *buf;
+
+    buf = FindSecurityHeader();
+    assert(buf != NULL);
+
+    // Security Control
+    buf += kSecurityControlSize + kFrameCounterSize;
+
+    return buf;
+}
+
+uint8_t Frame::GetKeySourceLength(uint8_t aKeyIdMode)
+{
+    uint8_t rval = 0;
+
+    switch (aKeyIdMode)
+    {
+    case kKeyIdMode0:
+        rval = kKeySourceSizeMode0;
+        break;
+
+    case kKeyIdMode1:
+        rval = kKeySourceSizeMode1;
+        break;
+
+    case kKeyIdMode2:
+        rval = kKeySourceSizeMode2;
+        break;
+
+    case kKeyIdMode3:
+        rval = kKeySourceSizeMode3;
+        break;
+    }
+
+    return rval;
+}
+
+void Frame::SetKeySource(const uint8_t *aKeySource)
+{
+    uint8_t keySourceLength;
+    uint8_t *buf;
+
+    buf = FindSecurityHeader();
+    assert(buf != NULL);
+
+    keySourceLength = GetKeySourceLength(buf[0] & kKeyIdModeMask);
+
+    buf += kSecurityControlSize + kFrameCounterSize;
+
+    memcpy(buf, aKeySource, keySourceLength);
+}
+
 ThreadError Frame::GetKeyId(uint8_t &aKeyId)
 {
     ThreadError error = kThreadError_None;
+    uint8_t keySourceLength;
     uint8_t *buf;
 
     VerifyOrExit((buf = FindSecurityHeader()) != NULL, error = kThreadError_Parse);
 
-    // Security Control + Frame Counter
-    buf += kSecurityControlSize + kFrameCounterSize;
+    keySourceLength = GetKeySourceLength(buf[0] & kKeyIdModeMask);
+
+    buf += kSecurityControlSize + kFrameCounterSize + keySourceLength;
 
     aKeyId = buf[0];
 
@@ -624,13 +680,15 @@ exit:
 
 ThreadError Frame::SetKeyId(uint8_t aKeyId)
 {
+    uint8_t keySourceLength;
     uint8_t *buf;
 
     buf = FindSecurityHeader();
     assert(buf != NULL);
 
-    // Security Control + Frame Counter
-    buf += kSecurityControlSize + kFrameCounterSize;
+    keySourceLength = GetKeySourceLength(buf[0] & kKeyIdModeMask);
+
+    buf += kSecurityControlSize + kFrameCounterSize + keySourceLength;
 
     buf[0] = aKeyId;
 
@@ -805,19 +863,19 @@ uint8_t *Frame::GetPayload(void)
         switch (securityControl & kKeyIdModeMask)
         {
         case kKeyIdMode0:
-            cur += kKeyIdLengthMode0;
+            cur += kKeySourceSizeMode0;
             break;
 
         case kKeyIdMode1:
-            cur += kKeyIdLengthMode1;
+            cur += kKeySourceSizeMode1 + kKeyIndexSize;
             break;
 
         case kKeyIdMode2:
-            cur += kKeyIdLengthMode2;
+            cur += kKeySourceSizeMode2 + kKeyIndexSize;
             break;
 
         case kKeyIdMode3:
-            cur += kKeyIdLengthMode3;
+            cur += kKeySourceSizeMode3 + kKeyIndexSize;
             break;
         }
     }

src/core/mac/mac_frame.hpp

@@ -219,6 +219,13 @@ public:
         kKeyIdMode3           = 3 << 3,
         kKeyIdModeMask        = 3 << 3,
 
+        kKeySourceSizeMode0   = 0,
+        kKeySourceSizeMode1   = 0,
+        kKeySourceSizeMode2   = 4,
+        kKeySourceSizeMode3   = 8,
+
+        kKeyIndexSize         = sizeof(uint8_t),
+
         kMacCmdAssociationRequest          = 1,
         kMacCmdAssociationResponse         = 2,
         kMacCmdDisassociationNotification  = 3,
@@ -449,6 +456,22 @@ public:
      */
     ThreadError SetFrameCounter(uint32_t aFrameCounter);
 
+    /**
+     * This method returns a pointer to the Key Source.
+     *
+     * @returns A pointer to the Key Source.
+     *
+     */
+    const uint8_t *GetKeySource(void);
+
+    /**
+     * This method sets the Key Source.
+     *
+     * @param[in]  aKeySource  A pointer to the Key Source value.
+     *
+     */
+    void SetKeySource(const uint8_t *aKeySource);
+
     /**
      * This method gets the Key Identifier.
      *
@@ -663,20 +686,13 @@ public:
     uint8_t *GetFooter(void);
 
 private:
-    enum
-    {
-        kKeyIdLengthMode0 = 0,   ///< Mode 0 Key ID Length in bytes (IEEE 802.15.4-2006)
-        kKeyIdLengthMode1 = 1,   ///< Mode 1 Key ID Length in bytes (IEEE 802.15.4-2006)
-        kKeyIdLengthMode2 = 5,   ///< Mode 2 Key ID Length in bytes (IEEE 802.15.4-2006)
-        kKeyIdLengthMode3 = 9,   ///< Mode 3 Key ID Length in bytes (IEEE 802.15.4-2006)
-    };
-
     uint8_t *FindSequence(void);
     uint8_t *FindDstPanId(void);
     uint8_t *FindDstAddr(void);
     uint8_t *FindSrcPanId(void);
     uint8_t *FindSrcAddr(void);
     uint8_t *FindSecurityHeader(void);
+    static uint8_t GetKeySourceLength(uint8_t aKeyIdMode);
 };
 
 /**

src/core/thread/mle.cpp

@@ -1421,7 +1421,6 @@ ThreadError Mle::SendAnnounce(uint8_t aChannel)
     PanIdTlv panid;
     Ip6::Address destination;
     Message *message;
-    (void)aChannel;
 
     VerifyOrExit((message = mSocket.NewMessage(0)) != NULL, ;);
     message->SetSubType(Message::kSubTypeMleAnnounce);