File content as of revision 9:329af8cdc923:

/* mbed Microcontroller Library
 * Copyright (c) 2006-2013 ARM Limited
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef __BLE_GARAGEM_SERVICE_H__
#define __BLE_GARAGEM_SERVICE_H__
#include "History.h"

#define SHARED_SECRET   "ABRE-TE"

#define GARAGEM_OK                          0
#define GARAGEM_ERROR_REPETITION_ATTACK     1
#define GARAGEM_ERROR_WRONG_SHARED_SECRET   2


class GaragemService {
public:
    const static uint16_t GARAGEM_SERVICE_UUID              = 0x2000;
    const static uint16_t GARAGEM_CHALLENGE_CHARACTERISTIC_UUID = 0x2001;
    const static uint16_t GARAGEM_LAST_OPEN_TS_UUID = 0x2002;
    const static uint16_t GARAGEM_LAST_OPEN_ID_UUID = 0x2003;

    GaragemService(BLE &_ble) :
        ble(_ble), 
        GaragemChallenge(GARAGEM_CHALLENGE_CHARACTERISTIC_UUID, (uint8_t *)"INIT"),
        GaragemLastOpenTS(GARAGEM_LAST_OPEN_TS_UUID, 0),
        GaragemLastOpenID(GARAGEM_LAST_OPEN_ID_UUID, (uint8_t *)"INIT")
    {
        GattCharacteristic *charTable[] = {&GaragemChallenge, &GaragemLastOpenTS, &GaragemLastOpenID};
        GattService         GaragemService(GARAGEM_SERVICE_UUID, charTable, sizeof(charTable) / sizeof(GattCharacteristic *));
        ble.gattServer().addService(GaragemService);
    }

    GattAttribute::Handle_t getChallengeHandle() const {
        return GaragemChallenge.getValueHandle();
    }
    
    int checkMessage(uint8_t *msg) {
        DBG("WHAT ? %s\r\n", (char *) msg);

        uint64_t token;
        char syskey[8];
        memcpy(&token, msg, 8);
        memcpy(&syskey, &msg[8], 8);
        DBG("TS=%lu\tID=%c%c%c%c\tSYSKEY=%s\r\n", *((uint32_t *) msg), msg[4], msg[5], msg[6], msg[7], &msg[8]); 

        //check we are not a victim of a repetion attack
        if(history.last_ts() >= (uint32_t) msg[0]) {
            DBG("HA HA repetion here...\r\n");
            return GARAGEM_ERROR_REPETITION_ATTACK;
        }
        
        if (strncmp(syskey,SHARED_SECRET,7)==0) {//TODO MOVE TO 8 CHARS
            //Save our success
            history.save(token);
            ble.gattServer().write(GaragemLastOpenTS.getValueHandle(), (const uint8_t *)&msg[0], 4*sizeof(uint8_t));
            ble.gattServer().write(GaragemLastOpenID.getValueHandle(), (const uint8_t *)&msg[4], 4*sizeof(uint8_t));
        
            return GARAGEM_OK;
        } else {
            return GARAGEM_ERROR_WRONG_SHARED_SECRET;
        }
    }
    
private:
    BLE   &ble;
    WriteOnlyArrayGattCharacteristic<uint8_t, 16>  GaragemChallenge;
    ReadOnlyGattCharacteristic<uint32_t> GaragemLastOpenTS;
    ReadOnlyArrayGattCharacteristic<uint8_t, 4> GaragemLastOpenID;
    
    History<16> history;
};

#endif /* #ifndef __BLE_GARAGEM_SERVICE_H__ */