cmm_wpa.c

Linux下的RT系列无线网卡驱动,可以直接在x86平台上编译

			
    	}
		else
    	{
			DBGPRINT(RT_DEBUG_ERROR, ("ERROR: KDE format length is too short \n"));
	        return FALSE;
    	}

		DBGPRINT(RT_DEBUG_TRACE, ("GTK in KDE format ,DefaultKeyID=%d, KeyLen=%d \n", DefaultIdx, GTKLEN));
		// skip it
		pMyKeyData += 8;
		KeyDataLength -= 8;
		
	}
	else if (!bWPA2 && MsgType == EAPOL_GROUP_MSG_1)
	{
		DefaultIdx = GroupKeyIndex;
		DBGPRINT(RT_DEBUG_TRACE, ("GTK DefaultKeyID=%d \n", DefaultIdx));
	}
		
	// Sanity check - shared key index must be 1 ~ 3
	if (DefaultIdx < 1 || DefaultIdx > 3)
    {
     	DBGPRINT(RT_DEBUG_ERROR, ("ERROR: GTK Key index(%d) is invalid in %s %s \n", DefaultIdx, ((bWPA2) ? "WPA2" : "WPA"), GetEapolMsgType(MsgType)));
        return FALSE;
    } 


#ifdef CONFIG_STA_SUPPORT
	// Todo
#endif // CONFIG_STA_SUPPORT //

	return TRUE;
 
}


/*
	========================================================================
	
	Routine Description:
		Construct EAPoL message for WPA handshaking 
		Its format is below,
		
		+--------------------+
		| Protocol Version	 |  1 octet
		+--------------------+
		| Protocol Type		 |	1 octet	
		+--------------------+
		| Body Length		 |  2 octets
		+--------------------+
		| Descriptor Type	 |	1 octet
		+--------------------+
		| Key Information    |	2 octets
		+--------------------+
		| Key Length	     |  1 octet
		+--------------------+
		| Key Repaly Counter |	8 octets
		+--------------------+
		| Key Nonce		     |  32 octets
		+--------------------+
		| Key IV			 |  16 octets
		+--------------------+
		| Key RSC			 |  8 octets
		+--------------------+
		| Key ID or Reserved |	8 octets
		+--------------------+
		| Key MIC			 |	8 octets
		+--------------------+
		| Key Data Length	 |	2 octets
		+--------------------+
		| Key Data			 |	n octets
		+--------------------+
		

	Arguments:
		pAd			Pointer	to our adapter
				
	Return Value:
		None
		
	Note:
		
	========================================================================
*/
VOID	ConstructEapolMsg(
	IN 	PRTMP_ADAPTER    	pAd,
    IN 	UCHAR				AuthMode,
    IN 	UCHAR				WepStatus,
    IN 	UCHAR				GroupKeyWepStatus,
    IN 	UCHAR				MsgType,  
    IN	UCHAR				DefaultKeyIdx,
    IN 	UCHAR				*ReplayCounter,
	IN 	UCHAR				*KeyNonce,
	IN	UCHAR				*TxRSC,
	IN	UCHAR				*PTK,
	IN	UCHAR				*GTK,
	IN	UCHAR				*RSNIE,
	IN	UCHAR				RSNIE_Len,
    OUT PEAPOL_PACKET       pMsg)
{
	BOOLEAN	bWPA2 = FALSE;

	// Choose WPA2 or not
	if ((AuthMode == Ndis802_11AuthModeWPA2) || (AuthMode == Ndis802_11AuthModeWPA2PSK))
		bWPA2 = TRUE;
		
    // Init Packet and Fill header    
    pMsg->ProVer = EAPOL_VER;
    pMsg->ProType = EAPOLKey;

	// Default 95 bytes, the EAPoL-Key descriptor exclude Key-data field
	pMsg->Body_Len[1] = LEN_EAPOL_KEY_MSG;  

	// Fill in EAPoL descriptor
	if (bWPA2)
		pMsg->KeyDesc.Type = WPA2_KEY_DESC;
	else
		pMsg->KeyDesc.Type = WPA1_KEY_DESC;
			
	// Fill in Key information, refer to IEEE Std 802.11i-2004 page 78 
	// When either the pairwise or the group cipher is AES, the DESC_TYPE_AES(2) shall be used.
	pMsg->KeyDesc.KeyInfo.KeyDescVer = 
        	(((WepStatus == Ndis802_11Encryption3Enabled) || (GroupKeyWepStatus == Ndis802_11Encryption3Enabled)) ? (DESC_TYPE_AES) : (DESC_TYPE_TKIP));

	// Specify Key Type as Group(0) or Pairwise(1)
	if (MsgType >= EAPOL_GROUP_MSG_1)
		pMsg->KeyDesc.KeyInfo.KeyType = GROUPKEY;
	else
		pMsg->KeyDesc.KeyInfo.KeyType = PAIRWISEKEY;

	// Specify Key Index, only group_msg1_WPA1
	if (!bWPA2 && (MsgType >= EAPOL_GROUP_MSG_1))
		pMsg->KeyDesc.KeyInfo.KeyIndex = DefaultKeyIdx;
	
	if (MsgType == EAPOL_PAIR_MSG_3)
		pMsg->KeyDesc.KeyInfo.Install = 1;
	
	if ((MsgType == EAPOL_PAIR_MSG_1) || (MsgType == EAPOL_PAIR_MSG_3) || (MsgType == EAPOL_GROUP_MSG_1))
		pMsg->KeyDesc.KeyInfo.KeyAck = 1;

	if (MsgType != EAPOL_PAIR_MSG_1)	
		pMsg->KeyDesc.KeyInfo.KeyMic = 1;
 
	if ((bWPA2 && (MsgType >= EAPOL_PAIR_MSG_3)) || (!bWPA2 && (MsgType >= EAPOL_GROUP_MSG_1)))
    {                        
       	pMsg->KeyDesc.KeyInfo.Secure = 1;                   
    }

	if (bWPA2 && ((MsgType == EAPOL_PAIR_MSG_3) || (MsgType == EAPOL_GROUP_MSG_1)))
    {                               	
        pMsg->KeyDesc.KeyInfo.EKD_DL = 1;            
    }

#ifdef BIG_ENDIAN
	// key Information element has done. 
	// Swap byte-order for big-endian platforn
	*(USHORT *)(&pMsg->KeyDesc.KeyInfo) = SWAP16(*(USHORT *)(&pMsg->KeyDesc.KeyInfo));
#endif

	// Fill in Key Length
	{
		if (MsgType >= EAPOL_GROUP_MSG_1)
		{
			// the length of group key cipher
			pMsg->KeyDesc.KeyLength[1] = ((GroupKeyWepStatus == Ndis802_11Encryption2Enabled) ? TKIP_GTK_LENGTH : LEN_AES_KEY);
		}
		else
		{
			// the length of pairwise key cipher
			pMsg->KeyDesc.KeyLength[1] = ((WepStatus == Ndis802_11Encryption2Enabled) ? LEN_TKIP_KEY : LEN_AES_KEY);			
		}				
	}			
	
 	// Fill in replay counter        		
    NdisMoveMemory(pMsg->KeyDesc.ReplayCounter, ReplayCounter, LEN_KEY_DESC_REPLAY);

	// Fill Key Nonce field		  
	// ANonce : pairwise_msg1 & pairwise_msg3
	// SNonce : pairwise_msg2
	// GNonce : group_msg1_wpa1	
	if ((MsgType <= EAPOL_PAIR_MSG_3) || ((!bWPA2 && (MsgType == EAPOL_GROUP_MSG_1))))
    	NdisMoveMemory(pMsg->KeyDesc.KeyNonce, KeyNonce, LEN_KEY_DESC_NONCE);

	// Fill key IV - WPA2 as 0, WPA1 as random
	if (!bWPA2 && (MsgType == EAPOL_GROUP_MSG_1))
	{		
		// Suggest IV be random number plus some number,
		NdisMoveMemory(pMsg->KeyDesc.KeyIv, &KeyNonce[16], LEN_KEY_DESC_IV);		
        pMsg->KeyDesc.KeyIv[15] += 2;		
	}
	
    // Fill Key RSC field        
    // It contains the RSC for the GTK being installed.
	if ((MsgType == EAPOL_PAIR_MSG_3 && bWPA2) || (MsgType == EAPOL_GROUP_MSG_1))
	{		
        NdisMoveMemory(pMsg->KeyDesc.KeyRsc, TxRSC, 6);
	}

	// Clear Key MIC field for MIC calculation later   
    NdisZeroMemory(pMsg->KeyDesc.KeyMic, LEN_KEY_DESC_MIC);
	
	ConstructEapolKeyData(pAd, 
						  AuthMode,
						  WepStatus,
						  GroupKeyWepStatus, 
						  MsgType, 
						  DefaultKeyIdx, 
						  bWPA2, 
						  PTK,
						  GTK,
						  RSNIE,
						  RSNIE_Len,
						  pMsg);
 
	// Calculate MIC and fill in KeyMic Field except Pairwise Msg 1.
	if (MsgType != EAPOL_PAIR_MSG_1)
	{
		CalculateMIC(pAd, WepStatus, PTK, pMsg);
	}

	DBGPRINT(RT_DEBUG_TRACE, ("===> ConstructEapolMsg for %s %s\n", ((bWPA2) ? "WPA2" : "WPA"), GetEapolMsgType(MsgType)));
	DBGPRINT(RT_DEBUG_TRACE, ("	     Body length = %d \n", pMsg->Body_Len[1]));
	DBGPRINT(RT_DEBUG_TRACE, ("	     Key length  = %d \n", pMsg->KeyDesc.KeyLength[1]));


}

/*
	========================================================================
	
	Routine Description:
		Construct the Key Data field of EAPoL message 

	Arguments:
		pAd			Pointer	to our adapter
		Elem		Message body
		
	Return Value:
		None
		
	Note:
		
	========================================================================
*/
VOID	ConstructEapolKeyData(
	IN	PRTMP_ADAPTER	pAd,
	IN	UCHAR			AuthMode,
	IN	UCHAR			WepStatus,
	IN	UCHAR			GroupKeyWepStatus,
	IN 	UCHAR			MsgType,
	IN	UCHAR			DefaultKeyIdx,
	IN	BOOLEAN			bWPA2Capable,
	IN	UCHAR			*PTK,
	IN	UCHAR			*GTK,
	IN	UCHAR			*RSNIE,
	IN	UCHAR			RSNIE_LEN,
	OUT PEAPOL_PACKET   pMsg)
{
	UCHAR		*mpool, *Key_Data, *Rc4GTK;  
	UCHAR       ekey[(LEN_KEY_DESC_IV+LEN_EAP_EK)];   
	UCHAR		data_offset;


	if (MsgType == EAPOL_PAIR_MSG_1 || MsgType == EAPOL_PAIR_MSG_4 || MsgType == EAPOL_GROUP_MSG_2)
		return;
 
	// allocate memory pool
	os_alloc_mem(pAd, (PUCHAR *)&mpool, 1500);

    if (mpool == NULL)
		return;
        
	/* Rc4GTK Len = 512 */
	Rc4GTK = (UCHAR *) ROUND_UP(mpool, 4);
	/* Key_Data Len = 512 */
	Key_Data = (UCHAR *) ROUND_UP(Rc4GTK + 512, 4);

	NdisZeroMemory(Key_Data, 512);
	pMsg->KeyDesc.KeyDataLen[1] = 0;
	data_offset = 0;
	
	// Encapsulate RSNIE in pairwise_msg2 & pairwise_msg3		
	if (RSNIE_LEN && ((MsgType == EAPOL_PAIR_MSG_2) || (MsgType == EAPOL_PAIR_MSG_3)))
	{
		if (bWPA2Capable)			
			Key_Data[data_offset + 0] = IE_WPA2;		
		else						 				
			Key_Data[data_offset + 0] = IE_WPA;            			
		
        Key_Data[data_offset + 1] = RSNIE_LEN;
		NdisMoveMemory(&Key_Data[data_offset + 2], RSNIE, RSNIE_LEN);
		data_offset += (2 + RSNIE_LEN);
	}

	// Encapsulate KDE format in pairwise_msg3_WPA2 & group_msg1_WPA2
	if (bWPA2Capable && ((MsgType == EAPOL_PAIR_MSG_3) || (MsgType == EAPOL_GROUP_MSG_1)))
	{
		// Key Data Encapsulation (KDE) format - 802.11i-2004  Figure-43w and Table-20h
        Key_Data[data_offset + 0] = 0xDD;

		if (GroupKeyWepStatus == Ndis802_11Encryption3Enabled)
		{
			Key_Data[data_offset + 1] = 0x16;// 4+2+16(OUI+DataType+DataField)			
		}
		else
		{
			Key_Data[data_offset + 1] = 0x26;// 4+2+32(OUI+DataType+DataField)			
		}
		
        Key_Data[data_offset + 2] = 0x00;
        Key_Data[data_offset + 3] = 0x0F;
        Key_Data[data_offset + 4] = 0xAC;
        Key_Data[data_offset + 5] = 0x01;

		// GTK KDE format - 802.11i-2004  Figure-43x
        Key_Data[data_offset + 6] = (DefaultKeyIdx & 0x03);
        Key_Data[data_offset + 7] = 0x00;	// Reserved Byte
				
		data_offset += 8;
	}


	// Encapsulate GTK and encrypt the key-data field with KEK.
	// Only for pairwise_msg3_WPA2 and group_msg1
	if ((MsgType == EAPOL_PAIR_MSG_3 && bWPA2Capable) || (MsgType == EAPOL_GROUP_MSG_1))
	{		
		// Fill in GTK 
		if (GroupKeyWepStatus == Ndis802_11Encryption3Enabled)
		{			
			NdisMoveMemory(&Key_Data[data_offset], GTK, LEN_AES_KEY);
			data_offset += LEN_AES_KEY;
		}
		else
		{			
			NdisMoveMemory(&Key_Data[data_offset], GTK, TKIP_GTK_LENGTH);
			data_offset += TKIP_GTK_LENGTH;
		}

		// Still dont know why, but if not append will occur "GTK not include in MSG3"
		// Patch for compatibility between zero config and funk
		if (MsgType == EAPOL_PAIR_MSG_3 && bWPA2Capable)
		{
			if (GroupKeyWepStatus == Ndis802_11Encryption3Enabled)
			{
				Key_Data[data_offset + 0] = 0xDD;
				Key_Data[data_offset + 1] = 0;
				data_offset += 2;
			}
			else
			{
				Key_Data[data_offset + 0] = 0xDD;
				Key_Data[data_offset + 1] = 0;
				Key_Data[data_offset + 2] = 0;
				Key_Data[data_offset + 3] = 0;
				Key_Data[data_offset + 4] = 0;
				Key_Data[data_offset + 5] = 0;
				data_offset += 6;
			}
		}

		// Encrypt the data material in key data field
		if (WepStatus == Ndis802_11Encryption3Enabled)
		{
			AES_GTK_KEY_WRAP(&PTK[16], Key_Data, data_offset, Rc4GTK);
            // AES wrap function will grow 8 bytes in length
            data_offset += 8;            				
		}
		else
		{
			// PREPARE Encrypted  "Key DATA" field.  (Encrypt GTK with RC4, usinf PTK[16]->[31] as Key, IV-field as IV)
			// put TxTsc in Key RSC field
			pAd->PrivateInfo.FCSCRC32 = PPPINITFCS32;   //Init crc32.

			// ekey is the contanetion of IV-field, and PTK[16]->PTK[31]
			NdisMoveMemory(ekey, pMsg->KeyDesc.KeyIv, LEN_KEY_DESC_IV);
			NdisMoveMemory(&ekey[LEN_KEY_DESC_IV], &PTK[16], LEN_EAP_EK);
			ARCFOUR_INIT(&pAd->PrivateInfo.WEPCONTEXT, ekey, sizeof(ekey));  //INIT SBOX, KEYLEN+3(IV)
			pAd->PrivateInfo.FCSCRC32 = RTMP_CALC_FCS32(pAd->PrivateInfo.FCSCRC32, Key_Data, data_offset);
			WPAARCFOUR_ENCRYPT(&pAd->PrivateInfo.WEPCONTEXT, Rc4GTK, Key_Data, data_offset);  
		}

		NdisMoveMemory(pMsg->KeyDesc.KeyData, Rc4GTK, data_offset);
	}
	else
	{
		NdisMoveMemory(pMsg->KeyDesc.KeyData, Key_Data, data_offset);
	}

	// set key data length field and total length
	pMsg->KeyDesc.KeyDataLen[1] = data_offset;		
    pMsg->Body_Len[1] += data_offset;

	os_free_mem(pAd, mpool);

}


VOID	CalculateMIC(
	IN	PRTMP_ADAPTER	pAd,
	IN	UCHAR			PeerWepStatus,
	IN	UCHAR			*PTK,
	OUT PEAPOL_PACKET   pMsg)
{
    UCHAR   *OutBuffer;
	ULONG	FrameLen = 0;
	UCHAR	mic[LEN_KEY_DESC_MIC];
	UCHAR	digest[80];

	// allocate memory for MIC calculation
	os_alloc_mem(pAd, (PUCHAR *)&OutBuffer, 512);

    if (OutBuffer == NULL)
    {
		DBGPRINT(RT_DEBUG_ERROR, ("!!!CalculateMIC: no memory!!!\n"));
		return;
    }
		
	// make a frame for calculating MIC.
    MakeOutgoingFrame(OutBuffer,            	&FrameLen,
                      pMsg->Body_Len[1] + 4,  	pMsg,
                      END_OF_ARGS);

	NdisZeroMemory(mic, sizeof(mic));
			
	// Calculate MIC
    if (PeerWepStatus == Ndis802_11Encryption3Enabled)
 	{
		HMAC_SHA1(OutBuffer,  FrameLen, PTK, LEN_EAP_MICK, digest);
		NdisMoveMemory(mic, digest, LEN_KEY_DESC_MIC);
	}
	else
	{
		hmac_md5(PTK,  LEN_EAP_MICK, OutBuffer, FrameLen, mic);
	}

	NdisMoveMemory(pMsg->KeyDesc.KeyMic, mic, LEN_KEY_DESC_MIC);

	os_free_mem(pAd, OutBuffer);
}