aws_if.c

// Troi-Ryan Stoeffler
// Corbin Harrell

// standard includes
#include <stdio.h>
#include <stdbool.h>

// Simplelink includes
#include "simplelink.h"

//Driverlib includes
#include "hw_types.h"
#include "hw_ints.h"
#include "rom.h"
#include "rom_map.h"
#include "interrupt.h"
#include "prcm.h"
#include "utils.h"
#include "uart.h"

//Common interface includes
#include "gpio_if.h"
#include "common.h"
#include "uart_if.h"
#include "aws_if.h"

//*****************************************************************************
//                 GLOBAL VARIABLES -- Start
//*****************************************************************************
volatile unsigned long  g_ulStatus = 0;//SimpleLink Status
unsigned long  g_ulPingPacketsRecv = 0; //Number of Ping Packets received
unsigned long  g_ulGatewayIP = 0; //Network Gateway IP address
unsigned char  g_ucConnectionSSID[SSID_LEN_MAX+1]; //Connection SSID
unsigned char  g_ucConnectionBSSID[BSSID_LEN_MAX]; //Connection BSSID
signed char    *g_Host = SERVER_NAME;
SlDateTime g_time;
#if defined(ccs) || defined(gcc)
extern void (* const g_pfnVectors[])(void);
#endif
#if defined(ewarm)
extern uVectorEntry __vector_table;
#endif
//*****************************************************************************
//                 GLOBAL VARIABLES -- End: df
//*****************************************************************************

//*****************************************************************************
//
//! \brief The Function Handles WLAN Events
//!
//! \param[in]  pWlanEvent - Pointer to WLAN Event Info
//!
//! \return None
//!
//*****************************************************************************
void SimpleLinkWlanEventHandler(SlWlanEvent_t *pWlanEvent) {
    if(!pWlanEvent) {
        return;
    }

    switch(pWlanEvent->Event) {
        case SL_WLAN_CONNECT_EVENT: {
            SET_STATUS_BIT(g_ulStatus, STATUS_BIT_CONNECTION);

            //
            // Information about the connected AP (like name, MAC etc) will be
            // available in 'slWlanConnectAsyncResponse_t'.
            // Applications can use it if required
            //
            //  slWlanConnectAsyncResponse_t *pEventData = NULL;
            // pEventData = &pWlanEvent->EventData.STAandP2PModeWlanConnected;
            //

            // Copy new connection SSID and BSSID to global parameters
            memcpy(g_ucConnectionSSID,pWlanEvent->EventData.
                   STAandP2PModeWlanConnected.ssid_name,
                   pWlanEvent->EventData.STAandP2PModeWlanConnected.ssid_len);
            memcpy(g_ucConnectionBSSID,
                   pWlanEvent->EventData.STAandP2PModeWlanConnected.bssid,
                   SL_BSSID_LENGTH);

            UART_PRINT("[WLAN EVENT] STA Connected to the AP: %s , "
                       "BSSID: %x:%x:%x:%x:%x:%x\n\r",
                       g_ucConnectionSSID,g_ucConnectionBSSID[0],
                       g_ucConnectionBSSID[1],g_ucConnectionBSSID[2],
                       g_ucConnectionBSSID[3],g_ucConnectionBSSID[4],
                       g_ucConnectionBSSID[5]);
        }
        break;

        case SL_WLAN_DISCONNECT_EVENT: {
            slWlanConnectAsyncResponse_t*  pEventData = NULL;

            CLR_STATUS_BIT(g_ulStatus, STATUS_BIT_CONNECTION);
            CLR_STATUS_BIT(g_ulStatus, STATUS_BIT_IP_AQUIRED);

            pEventData = &pWlanEvent->EventData.STAandP2PModeDisconnected;

            // If the user has initiated 'Disconnect' request,
            //'reason_code' is SL_USER_INITIATED_DISCONNECTION
            if(SL_USER_INITIATED_DISCONNECTION == pEventData->reason_code) {
                UART_PRINT("[WLAN EVENT]Device disconnected from the AP: %s,"
                    "BSSID: %x:%x:%x:%x:%x:%x on application's request \n\r",
                           g_ucConnectionSSID,g_ucConnectionBSSID[0],
                           g_ucConnectionBSSID[1],g_ucConnectionBSSID[2],
                           g_ucConnectionBSSID[3],g_ucConnectionBSSID[4],
                           g_ucConnectionBSSID[5]);
            }
            else {
                UART_PRINT("[WLAN ERROR]Device disconnected from the AP AP: %s, "
                           "BSSID: %x:%x:%x:%x:%x:%x on an ERROR..!! \n\r",
                           g_ucConnectionSSID,g_ucConnectionBSSID[0],
                           g_ucConnectionBSSID[1],g_ucConnectionBSSID[2],
                           g_ucConnectionBSSID[3],g_ucConnectionBSSID[4],
                           g_ucConnectionBSSID[5]);
            }
            memset(g_ucConnectionSSID,0,sizeof(g_ucConnectionSSID));
            memset(g_ucConnectionBSSID,0,sizeof(g_ucConnectionBSSID));
        }
        break;

        default: {
            UART_PRINT("[WLAN EVENT] Unexpected event [0x%x]\n\r",
                       pWlanEvent->Event);
        }
        break;
    }
}

//*****************************************************************************
//
//! \brief This function handles network events such as IP acquisition, IP
//!           leased, IP released etc.
//!
//! \param[in]  pNetAppEvent - Pointer to NetApp Event Info
//!
//! \return None
//!
//*****************************************************************************
void SimpleLinkNetAppEventHandler(SlNetAppEvent_t *pNetAppEvent) {
    if(!pNetAppEvent) {
        return;
    }

    switch(pNetAppEvent->Event) {
        case SL_NETAPP_IPV4_IPACQUIRED_EVENT: {
            SlIpV4AcquiredAsync_t *pEventData = NULL;

            SET_STATUS_BIT(g_ulStatus, STATUS_BIT_IP_AQUIRED);

            //Ip Acquired Event Data
            pEventData = &pNetAppEvent->EventData.ipAcquiredV4;

            //Gateway IP address
            g_ulGatewayIP = pEventData->gateway;

            UART_PRINT("[NETAPP EVENT] IP Acquired: IP=%d.%d.%d.%d , "
                       "Gateway=%d.%d.%d.%d\n\r",
            SL_IPV4_BYTE(pNetAppEvent->EventData.ipAcquiredV4.ip,3),
            SL_IPV4_BYTE(pNetAppEvent->EventData.ipAcquiredV4.ip,2),
            SL_IPV4_BYTE(pNetAppEvent->EventData.ipAcquiredV4.ip,1),
            SL_IPV4_BYTE(pNetAppEvent->EventData.ipAcquiredV4.ip,0),
            SL_IPV4_BYTE(pNetAppEvent->EventData.ipAcquiredV4.gateway,3),
            SL_IPV4_BYTE(pNetAppEvent->EventData.ipAcquiredV4.gateway,2),
            SL_IPV4_BYTE(pNetAppEvent->EventData.ipAcquiredV4.gateway,1),
            SL_IPV4_BYTE(pNetAppEvent->EventData.ipAcquiredV4.gateway,0));
        }
        break;

        default: {
            UART_PRINT("[NETAPP EVENT] Unexpected event [0x%x] \n\r",
                       pNetAppEvent->Event);
        }
        break;
    }
}


//*****************************************************************************
//
//! \brief This function handles HTTP server events
//!
//! \param[in]  pServerEvent - Contains the relevant event information
//! \param[in]    pServerResponse - Should be filled by the user with the
//!                                      relevant response information
//!
//! \return None
//!
//****************************************************************************
void SimpleLinkHttpServerCallback(SlHttpServerEvent_t *pHttpEvent, SlHttpServerResponse_t *pHttpResponse) {
    // Unused in this application
}

//*****************************************************************************
//
//! \brief This function handles General Events
//!
//! \param[in]     pDevEvent - Pointer to General Event Info
//!
//! \return None
//!
//*****************************************************************************
void SimpleLinkGeneralEventHandler(SlDeviceEvent_t *pDevEvent) {
    if(!pDevEvent) {
        return;
    }

    //
    // Most of the general errors are not FATAL are are to be handled
    // appropriately by the application
    //
    UART_PRINT("[GENERAL EVENT] - ID=[%d] Sender=[%d]\n\n",
               pDevEvent->EventData.deviceEvent.status,
               pDevEvent->EventData.deviceEvent.sender);
}


//*****************************************************************************
//
//! This function handles socket events indication
//!
//! \param[in]      pSock - Pointer to Socket Event Info
//!
//! \return None
//!
//*****************************************************************************
void SimpleLinkSockEventHandler(SlSockEvent_t *pSock) {
    if(!pSock) {
        return;
    }

    switch( pSock->Event ) {
        case SL_SOCKET_TX_FAILED_EVENT:
            switch( pSock->socketAsyncEvent.SockTxFailData.status) {
                case SL_ECLOSE:
                    UART_PRINT("[SOCK ERROR] - close socket (%d) operation "
                                "failed to transmit all queued packets\n\n",
                                    pSock->socketAsyncEvent.SockTxFailData.sd);
                    break;
                default:
                    UART_PRINT("[SOCK ERROR] - TX FAILED  :  socket %d , reason "
                                "(%d) \n\n",
                                pSock->socketAsyncEvent.SockTxFailData.sd, pSock->socketAsyncEvent.SockTxFailData.status);
                  break;
            }
            break;

        default:
            UART_PRINT("[SOCK EVENT] - Unexpected Event [%x0x]\n\n",pSock->Event);
          break;
    }
}


//*****************************************************************************
// SimpleLink Asynchronous Event Handlers -- End breadcrumb: s18_df
//*****************************************************************************


//*****************************************************************************
//
//! \brief This function initializes the application variables
//!
//! \param    0 on success else error code
//!
//! \return None
//!
//*****************************************************************************
static long InitializeAppVariables() {
    g_ulStatus = 0;
    g_ulGatewayIP = 0;
    g_Host = SERVER_NAME;
    memset(g_ucConnectionSSID,0,sizeof(g_ucConnectionSSID));
    memset(g_ucConnectionBSSID,0,sizeof(g_ucConnectionBSSID));
    return SUCCESS;
}


//*****************************************************************************
//! \brief This function puts the device in its default state. It:
//!           - Set the mode to STATION
//!           - Configures connection policy to Auto and AutoSmartConfig
//!           - Deletes all the stored profiles
//!           - Enables DHCP
//!           - Disables Scan policy
//!           - Sets Tx power to maximum
//!           - Sets power policy to normal
//!           - Unregister mDNS services
//!           - Remove all filters
//!
//! \param   none
//! \return  On success, zero is returned. On error, negative is returned
//*****************************************************************************
static long ConfigureSimpleLinkToDefaultState() {
    SlVersionFull   ver = {0};
    _WlanRxFilterOperationCommandBuff_t  RxFilterIdMask = {0};

    unsigned char ucVal = 1;
    unsigned char ucConfigOpt = 0;
    unsigned char ucConfigLen = 0;
    unsigned char ucPower = 0;

    long lRetVal = -1;
    long lMode = -1;

    lMode = sl_Start(0, 0, 0);
    ASSERT_ON_ERROR(lMode);

    // If the device is not in station-mode, try configuring it in station-mode
    if (ROLE_STA != lMode) {
        if (ROLE_AP == lMode) {
            // If the device is in AP mode, we need to wait for this event
            // before doing anything
            while(!IS_IP_ACQUIRED(g_ulStatus)) {
#ifndef SL_PLATFORM_MULTI_THREADED
              _SlNonOsMainLoopTask();
#endif
            }
        }

        // Switch to STA role and restart
        lRetVal = sl_WlanSetMode(ROLE_STA);
        ASSERT_ON_ERROR(lRetVal);

        lRetVal = sl_Stop(0xFF);
        ASSERT_ON_ERROR(lRetVal);

        lRetVal = sl_Start(0, 0, 0);
        ASSERT_ON_ERROR(lRetVal);

        // Check if the device is in station again
        if (ROLE_STA != lRetVal) {
            // We don't want to proceed if the device is not coming up in STA-mode
            return DEVICE_NOT_IN_STATION_MODE;
        }
    }

    // Get the device's version-information
    ucConfigOpt = SL_DEVICE_GENERAL_VERSION;
    ucConfigLen = sizeof(ver);
    lRetVal = sl_DevGet(SL_DEVICE_GENERAL_CONFIGURATION, &ucConfigOpt,
                                &ucConfigLen, (unsigned char *)(&ver));
    ASSERT_ON_ERROR(lRetVal);

    UART_PRINT("Host Driver Version: %s\n\r",SL_DRIVER_VERSION);
    UART_PRINT("Build Version %d.%d.%d.%d.31.%d.%d.%d.%d.%d.%d.%d.%d\n\r",
    ver.NwpVersion[0],ver.NwpVersion[1],ver.NwpVersion[2],ver.NwpVersion[3],
    ver.ChipFwAndPhyVersion.FwVersion[0],ver.ChipFwAndPhyVersion.FwVersion[1],
    ver.ChipFwAndPhyVersion.FwVersion[2],ver.ChipFwAndPhyVersion.FwVersion[3],
    ver.ChipFwAndPhyVersion.PhyVersion[0],ver.ChipFwAndPhyVersion.PhyVersion[1],
    ver.ChipFwAndPhyVersion.PhyVersion[2],ver.ChipFwAndPhyVersion.PhyVersion[3]);

    // Set connection policy to Auto + SmartConfig
    //      (Device's default connection policy)
    lRetVal = sl_WlanPolicySet(SL_POLICY_CONNECTION,
                                SL_CONNECTION_POLICY(1, 0, 0, 0, 1), NULL, 0);
    ASSERT_ON_ERROR(lRetVal);

    // Remove all profiles
    lRetVal = sl_WlanProfileDel(0xFF);
    ASSERT_ON_ERROR(lRetVal);



    //
    // Device in station-mode. Disconnect previous connection if any
    // The function returns 0 if 'Disconnected done', negative number if already
    // disconnected Wait for 'disconnection' event if 0 is returned, Ignore
    // other return-codes
    //
    lRetVal = sl_WlanDisconnect();
    if(0 == lRetVal) {
        // Wait
        while(IS_CONNECTED(g_ulStatus)) {
#ifndef SL_PLATFORM_MULTI_THREADED
              _SlNonOsMainLoopTask();
#endif
        }
    }

    // Enable DHCP client
    lRetVal = sl_NetCfgSet(SL_IPV4_STA_P2P_CL_DHCP_ENABLE,1,1,&ucVal);
    ASSERT_ON_ERROR(lRetVal);

    // Disable scan
    ucConfigOpt = SL_SCAN_POLICY(0);
    lRetVal = sl_WlanPolicySet(SL_POLICY_SCAN , ucConfigOpt, NULL, 0);
    ASSERT_ON_ERROR(lRetVal);

    // Set Tx power level for station mode
    // Number between 0-15, as dB offset from max power - 0 will set max power
    ucPower = 0;
    lRetVal = sl_WlanSet(SL_WLAN_CFG_GENERAL_PARAM_ID,
            WLAN_GENERAL_PARAM_OPT_STA_TX_POWER, 1, (unsigned char *)&ucPower);
    ASSERT_ON_ERROR(lRetVal);

    // Set PM policy to normal
    lRetVal = sl_WlanPolicySet(SL_POLICY_PM , SL_NORMAL_POLICY, NULL, 0);
    ASSERT_ON_ERROR(lRetVal);

    // Unregister mDNS services
    lRetVal = sl_NetAppMDNSUnRegisterService(0, 0);
    ASSERT_ON_ERROR(lRetVal);

    // Remove  all 64 filters (8*8)
    memset(RxFilterIdMask.FilterIdMask, 0xFF, 8);
    lRetVal = sl_WlanRxFilterSet(SL_REMOVE_RX_FILTER, (_u8 *)&RxFilterIdMask,
                       sizeof(_WlanRxFilterOperationCommandBuff_t));
    ASSERT_ON_ERROR(lRetVal);

    lRetVal = sl_Stop(SL_STOP_TIMEOUT);
    ASSERT_ON_ERROR(lRetVal);

    InitializeAppVariables();

    return lRetVal; // Success
}

//****************************************************************************
//
//! \brief Connecting to a WLAN Accesspoint
//!
//!  This function connects to the required AP (SSID_NAME) with Security
//!  parameters specified in te form of macros at the top of this file
//!
//! \param  None
//!
//! \return  0 on success else error code
//!
//! \warning    If the WLAN connection fails or we don't aquire an IP
//!            address, It will be stuck in this function forever.
//
//****************************************************************************
static long WlanConnect() {
    SlSecParams_t secParams = {0};
    long lRetVal = 0;

    secParams.Key = SECURITY_KEY;
    secParams.KeyLen = strlen(SECURITY_KEY);
    secParams.Type = SECURITY_TYPE;

    UART_PRINT("Attempting connection to access point: ");
    UART_PRINT(SSID_NAME);
    UART_PRINT("... ...");
    lRetVal = sl_WlanConnect(SSID_NAME, strlen(SSID_NAME), 0, &secParams, 0);
    ASSERT_ON_ERROR(lRetVal);

    UART_PRINT(" Connected!!!\n\r");


    // Wait for WLAN Event
    while((!IS_CONNECTED(g_ulStatus)) || (!IS_IP_ACQUIRED(g_ulStatus))) {
        // Toggle LEDs to Indicate Connection Progress
        _SlNonOsMainLoopTask();
        GPIO_IF_LedOff(MCU_IP_ALLOC_IND);
        MAP_UtilsDelay(800000);
        _SlNonOsMainLoopTask();
        GPIO_IF_LedOn(MCU_IP_ALLOC_IND);
        MAP_UtilsDelay(800000);
    }

    return SUCCESS;

}

long printErrConvenience(char * msg, long retVal) {
    UART_PRINT(msg);
    GPIO_IF_LedOn(MCU_RED_LED_GPIO);
    return retVal;
}


//*****************************************************************************
//
//! This function updates the date and time of CC3200.
//!
//! \param None
//!
//! \return
//!     0 for success, negative otherwise
//!
//*****************************************************************************
static int set_time() {
    long retVal;

    // if the __DATE__ macro exists, then update the time automatically using that
#ifdef __DATE__
    g_time.tm_day = (__DATE__[4] * 10) + __DATE__[5] - (ZEROCHAR * 11);
    g_time.tm_year = (__DATE__[7] * 1000) + (__DATE__[8] * 100) + (__DATE__[9] * 10) + __DATE__[10] - (ZEROCHAR * 1111);
    if (__DATE__[0] == 'F') g_time.tm_mon = 2;
    else if (__DATE__[0] == 'S') g_time.tm_mon = 9;
    else if (__DATE__[0] == 'O') g_time.tm_mon = 10;
    else if (__DATE__[0] == 'N') g_time.tm_mon = 11;
    else if (__DATE__[0] == 'D') g_time.tm_mon = 12;
    else if (__DATE__[0] == 'J' && __DATE__[1] == 'a') g_time.tm_mon = 1;
    else if (__DATE__[0] == 'M' && __DATE__[2] == 'r') g_time.tm_mon = 3;
    else if (__DATE__[0] == 'A' && __DATE__[1] == 'p') g_time.tm_mon = 4;
    else if (__DATE__[0] == 'M' && __DATE__[2] == 'y') g_time.tm_mon = 5;
    else if (__DATE__[0] == 'J' && __DATE__[2] == 'n') g_time.tm_mon = 6;
    else if (__DATE__[0] == 'J' && __DATE__[2] == 'l') g_time.tm_mon = 7;
    else if (__DATE__[0] == 'A' && __DATE__[1] == 'u') g_time.tm_mon = 8;
#else
    g_time.tm_day = DATE;
    g_time.tm_mon = MONTH;
    g_time.tm_year = YEAR;
#endif

    // if the __TIME__ macro exists, update the time to use those values
#ifdef __TIME__
    g_time.tm_sec = (__TIME__[6] * 10) + __TIME__[7] - (ZEROCHAR * 11);
    g_time.tm_hour = (__TIME__[0] * 10) + __TIME__[1] - (ZEROCHAR * 11);
    g_time.tm_min = (__TIME__[3] * 10) + __TIME__[4] - (ZEROCHAR * 11);
#else
    g_time.tm_sec = SECOND;
    g_time.tm_hour = HOUR;
    g_time.tm_min = MINUTE;
#endif

    retVal = sl_DevSet(SL_DEVICE_GENERAL_CONFIGURATION,
                          SL_DEVICE_GENERAL_CONFIGURATION_DATE_TIME,
                          sizeof(SlDateTime),(unsigned char *)(&g_time));

    ASSERT_ON_ERROR(retVal);
    return SUCCESS;
}

//*****************************************************************************
//
//! This function demonstrates how certificate can be used with SSL.
//! The procedure includes the following steps:
//! 1) connect to an open AP
//! 2) get the server name via a DNS request
//! 3) define all socket options and point to the CA certificate
//! 4) connect to the server via TCP
//!
//! \param None
//!
//! \return  0 on success else error code
//! \return  LED1 is turned solid in case of success
//!    LED2 is turned solid in case of failure
//!
//*****************************************************************************
static int tls_connect() {
    SlSockAddrIn_t    Addr;
    int    iAddrSize;
    unsigned char    ucMethod = SL_SO_SEC_METHOD_TLSV1_2;
    unsigned int uiIP;
//    unsigned int uiCipher = SL_SEC_MASK_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA;
    unsigned int uiCipher = SL_SEC_MASK_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256;
// SL_SEC_MASK_SSL_RSA_WITH_RC4_128_SHA
// SL_SEC_MASK_SSL_RSA_WITH_RC4_128_MD5
// SL_SEC_MASK_TLS_RSA_WITH_AES_256_CBC_SHA
// SL_SEC_MASK_TLS_DHE_RSA_WITH_AES_256_CBC_SHA
// SL_SEC_MASK_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
// SL_SEC_MASK_TLS_ECDHE_RSA_WITH_RC4_128_SHA
// SL_SEC_MASK_TLS_RSA_WITH_AES_128_CBC_SHA256
// SL_SEC_MASK_TLS_RSA_WITH_AES_256_CBC_SHA256
// SL_SEC_MASK_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
// SL_SEC_MASK_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 // does not work (-340, handshake fails)
    long lRetVal = -1;
    int iSockID;

    lRetVal = sl_NetAppDnsGetHostByName(g_Host, strlen((const char *)g_Host),
                                    (unsigned long*)&uiIP, SL_AF_INET);

    if(lRetVal < 0) {
        return printErrConvenience("Device couldn't retrieve the host name \n\r", lRetVal);
    }

    Addr.sin_family = SL_AF_INET;
    Addr.sin_port = sl_Htons(GOOGLE_DST_PORT);
    Addr.sin_addr.s_addr = sl_Htonl(uiIP);
    iAddrSize = sizeof(SlSockAddrIn_t);
    //
    // opens a secure socket
    //
    iSockID = sl_Socket(SL_AF_INET,SL_SOCK_STREAM, SL_SEC_SOCKET);
    if( iSockID < 0 ) {
        return printErrConvenience("Device unable to create secure socket \n\r", lRetVal);
    }

    //
    // configure the socket as TLS1.2
    //
    lRetVal = sl_SetSockOpt(iSockID, SL_SOL_SOCKET, SL_SO_SECMETHOD, &ucMethod,\
                               sizeof(ucMethod));
    if(lRetVal < 0) {
        return printErrConvenience("Device couldn't set socket options \n\r", lRetVal);
    }
    //
    //configure the socket as ECDHE RSA WITH AES256 CBC SHA
    //
    lRetVal = sl_SetSockOpt(iSockID, SL_SOL_SOCKET, SL_SO_SECURE_MASK, &uiCipher,\
                           sizeof(uiCipher));
    if(lRetVal < 0) {
        return printErrConvenience("Device couldn't set socket options \n\r", lRetVal);
    }



/////////////////////////////////
// START: COMMENT THIS OUT IF DISABLING SERVER VERIFICATION
    //
    //configure the socket with CA certificate - for server verification
    //
    lRetVal = sl_SetSockOpt(iSockID, SL_SOL_SOCKET, \
                           SL_SO_SECURE_FILES_CA_FILE_NAME, \
                           SL_SSL_CA_CERT, \
                           strlen(SL_SSL_CA_CERT));

    if(lRetVal < 0) {
        return printErrConvenience("Device couldn't set socket options \n\r", lRetVal);
    }
// END: COMMENT THIS OUT IF DISABLING SERVER VERIFICATION
/////////////////////////////////


    //configure the socket with Client Certificate - for server verification
    //
    lRetVal = sl_SetSockOpt(iSockID, SL_SOL_SOCKET, \
                SL_SO_SECURE_FILES_CERTIFICATE_FILE_NAME, \
                                    SL_SSL_CLIENT, \
                           strlen(SL_SSL_CLIENT));

    if(lRetVal < 0) {
        return printErrConvenience("Device couldn't set socket options \n\r", lRetVal);
    }

    //configure the socket with Private Key - for server verification
    //
    lRetVal = sl_SetSockOpt(iSockID, SL_SOL_SOCKET, \
            SL_SO_SECURE_FILES_PRIVATE_KEY_FILE_NAME, \
            SL_SSL_PRIVATE, \
                           strlen(SL_SSL_PRIVATE));

    if(lRetVal < 0) {
        return printErrConvenience("Device couldn't set socket options \n\r", lRetVal);
    }


    /* connect to the peer device - Google server */
    lRetVal = sl_Connect(iSockID, ( SlSockAddr_t *)&Addr, iAddrSize);

    if(lRetVal >= 0) {
        UART_PRINT("Device has connected to the website:");
        UART_PRINT(SERVER_NAME);
        UART_PRINT("\n\r");
    }
    else if(lRetVal == SL_ESECSNOVERIFY) {
        UART_PRINT("Device has connected to the website (UNVERIFIED):");
        UART_PRINT(SERVER_NAME);
        UART_PRINT("\n\r");
    }
    else if(lRetVal < 0) {
        UART_PRINT("Device couldn't connect to server:");
        UART_PRINT(SERVER_NAME);
        UART_PRINT("\n\r");
        return printErrConvenience("Device couldn't connect to server \n\r", lRetVal);
    }

    GPIO_IF_LedOff(MCU_RED_LED_GPIO);
    GPIO_IF_LedOn(MCU_GREEN_LED_GPIO);
    return iSockID;
}

int connectToAccessPoint() {
    long lRetVal = -1;
    GPIO_IF_LedConfigure(LED1|LED3);

    GPIO_IF_LedOff(MCU_RED_LED_GPIO);
    GPIO_IF_LedOff(MCU_GREEN_LED_GPIO);

    lRetVal = InitializeAppVariables();
    ASSERT_ON_ERROR(lRetVal);

    //
    // Following function configure the device to default state by cleaning
    // the persistent settings stored in NVMEM (viz. connection profiles &
    // policies, power policy etc)
    //
    // Applications may choose to skip this step if the developer is sure
    // that the device is in its default state at start of applicaton
    //
    // Note that all profiles and persistent settings that were done on the
    // device will be lost
    //
    lRetVal = ConfigureSimpleLinkToDefaultState();
    if(lRetVal < 0) {
      if (DEVICE_NOT_IN_STATION_MODE == lRetVal)
          UART_PRINT("Failed to configure the device in its default state \n\r");

      return lRetVal;
    }

    UART_PRINT("Device is configured in default state \n\r");

    CLR_STATUS_BIT_ALL(g_ulStatus);

    ///
    // Assumption is that the device is configured in station mode already
    // and it is in its default state
    //
    UART_PRINT("Opening sl_start\n\r");
    lRetVal = sl_Start(0, 0, 0);
    if (lRetVal < 0 || ROLE_STA != lRetVal) {
        UART_PRINT("Failed to start the device \n\r");
        return lRetVal;
    }

    UART_PRINT("Device started as STATION \n\r");

    //
    //Connecting to WLAN AP
    //
    lRetVal = WlanConnect();
    if(lRetVal < 0) {
        UART_PRINT("Failed to establish connection w/ an AP \n\r");
        GPIO_IF_LedOn(MCU_RED_LED_GPIO);
        return lRetVal;
    }

    UART_PRINT("Connection established w/ AP and IP is aquired \n\r");
    return 0;
}


// method that creates a GET request based
// and sends it to the given TLS port
static char* http_get(int iTLSSockID){
    char acSendBuff[512];
    static char acRecvbuff[1460];
    char* pcBufHeaders;
    int lRetVal = 0;

    // add the headers to the request
    pcBufHeaders = acSendBuff;
    strcpy(pcBufHeaders, GETHEADER);
    pcBufHeaders += strlen(GETHEADER);
    strcpy(pcBufHeaders, HOSTHEADER);
    pcBufHeaders += strlen(HOSTHEADER);
    strcpy(pcBufHeaders, CHEADER);
    pcBufHeaders += strlen(CHEADER);
    strcpy(pcBufHeaders, "\r\n\r\n");

    //
    // Send the packet to the server */
    //
    lRetVal = sl_Send(iTLSSockID, acSendBuff, strlen(acSendBuff), 0);
    if(lRetVal < 0) {
        sl_Close(iTLSSockID);
        GPIO_IF_LedOn(MCU_RED_LED_GPIO);
        return "";
    }
    lRetVal = sl_Recv(iTLSSockID, &acRecvbuff[0], sizeof(acRecvbuff), SL_MSG_DONTWAIT);
    if(lRetVal < 0 && lRetVal != -11) {
        GPIO_IF_LedOn(MCU_RED_LED_GPIO);
        return "";
    } else if(lRetVal == -11) {
        sprintf(acRecvbuff, "%s", "POLL");
    } else {
        acRecvbuff[lRetVal+1] = '\0';
    }

    return acRecvbuff;
}

// method that creates a POST request based on the string
// and sends it to the given TLS port
static char* http_post(int iTLSSockID, char *text){
    char acSendBuff[512];
    static char acRecvbuff[1460];
    char cCLLength[200];
    char* pcBufHeaders;
    int lRetVal = 0;

    // construct the headers
    pcBufHeaders = acSendBuff;
    strcpy(pcBufHeaders, POSTHEADER);
    pcBufHeaders += strlen(POSTHEADER);
    strcpy(pcBufHeaders, HOSTHEADER);
    pcBufHeaders += strlen(HOSTHEADER);
    strcpy(pcBufHeaders, CHEADER);
    pcBufHeaders += strlen(CHEADER);
    strcpy(pcBufHeaders, "\r\n\r\n");

    // get the entire data length
    int dataLength = strlen(DATA_PREF) + strlen((const char *) text) + strlen(DATA_SUFF);

    strcpy(pcBufHeaders, CTHEADER);
    pcBufHeaders += strlen(CTHEADER);
    strcpy(pcBufHeaders, CLHEADER1);

    // add the data length to the headers
    pcBufHeaders += strlen(CLHEADER1);
    sprintf(cCLLength, "%d", dataLength);

    strcpy(pcBufHeaders, cCLLength);
    pcBufHeaders += strlen(cCLLength);
    strcpy(pcBufHeaders, CLHEADER2);
    pcBufHeaders += strlen(CLHEADER2);

    // append the data to the request
    strcpy(pcBufHeaders, DATA_PREF);
    pcBufHeaders += strlen(DATA_PREF);
    strcpy(pcBufHeaders, (const char *) text);
    pcBufHeaders += strlen((const char *) text);
    strcpy(pcBufHeaders, DATA_SUFF);
    pcBufHeaders += strlen(DATA_SUFF);

    int testDataLength = strlen(pcBufHeaders);

    //
    // Send the packet to the server */
    //
    lRetVal = sl_Send(iTLSSockID, acSendBuff, strlen(acSendBuff), 0);
    if(lRetVal < 0) {
        sl_Close(iTLSSockID);
        GPIO_IF_LedOn(MCU_RED_LED_GPIO);
        return "";
    }
    lRetVal = sl_Recv(iTLSSockID, &acRecvbuff[0], sizeof(acRecvbuff), SL_MSG_DONTWAIT);
    if(lRetVal < 0 && lRetVal != -11) {
        GPIO_IF_LedOn(MCU_RED_LED_GPIO);
        return "";
    } else if(lRetVal == -11) {
        sprintf(acRecvbuff, "%s", "POLL");
    } else {
        acRecvbuff[lRetVal+1] = '\0';
    }

    return 0;
}

// return value and TLS port variable
static long accessReturnVal = -1;

void networkConnect(void) {
    //Connect the CC3200 to the local access point
    accessReturnVal = connectToAccessPoint();
    //Set time so that encryption can be used
    accessReturnVal = set_time();
    if(accessReturnVal < 0) {
        UART_PRINT("Unable to set time in the device");
        LOOP_FOREVER();
    }
    // update the accessReturnVal variable, and if successful set it to the
    // current TLS port
    accessReturnVal = tls_connect();
    if(accessReturnVal < 0) {
        ERR_PRINT(accessReturnVal);
    }
}

// kill the current network connection
void networkKill(void) {
    sl_Stop(SL_STOP_TIMEOUT);
}

static bool firstElem = true;
static char emptyString[] = "";
static char *newRequest = "";
// send the string over with TLS encryption
void buildRequest(char *var, char *text) {
    if(firstElem) {
        sprintf(newRequest, "%s\"%s\": \"%s\"", newRequest, var, text);
        firstElem = false;
    } else {
        sprintf(newRequest, "%s,\r\n\"%s\": \"%s\"", newRequest, var, text);
    }
}

char* sendRequest(void) {
    static char *returnVal;
    returnVal = http_post(accessReturnVal, newRequest);
    strcpy(newRequest, emptyString);
    firstElem = true;
    return returnVal;
}

char* receiveString(void) {
    return http_get(accessReturnVal);
}

char* networkReceive(void) {
    static char acRecvbuff[1460];
    int lRetVal = sl_Recv(accessReturnVal, &acRecvbuff[0], sizeof(acRecvbuff), SL_MSG_DONTWAIT);
    if(lRetVal < 0 && lRetVal != -11) {
        GPIO_IF_LedOn(MCU_RED_LED_GPIO);
        return "";
    } else if(lRetVal == -11) {
        sprintf(acRecvbuff, "%s", "POLL");
    } else {
        acRecvbuff[lRetVal+1] = '\0';
    }
    return acRecvbuff;
}