UbloxATCellularInterfaceN2xx.h

00001 /* Copyright (c) 2017 ARM Limited
00002  *
00003  * Licensed under the Apache License, Version 2.0 (the "License");
00004  * you may not use this file except in compliance with the License.
00005  * You may obtain a copy of the License at
00006  *
00007  *     http://www.apache.org/licenses/LICENSE-2.0
00008  *
00009  * Unless required by applicable law or agreed to in writing, software
00010  * distributed under the License is distributed on an "AS IS" BASIS,
00011  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00012  * See the License for the specific language governing permissions and
00013  * limitations under the License.
00014  */
00015 
00016 #ifndef _UBLOX_AT_CELLULAR_INTERFACE_N2XX_
00017 #define _UBLOX_AT_CELLULAR_INTERFACE_N2XX_
00018 
00019 #include "UbloxCellularBaseN2xx.h"
00020 #include "CellularBase.h"
00021 #include "NetworkStack.h"
00022 
00023 /** UbloxATCellularInterface class.
00024  *
00025  *  This uses the cellular-tuned IP stack that
00026  *  is on-board the cellular modem instead of the
00027  *  LWIP stack on the mbed MCU.
00028  *
00029  *  There are three advantages to using this mechanism:
00030  *
00031  *  1.  Since the modem interface remains in AT mode
00032  *      throughout, it is possible to continue using
00033  *      any AT commands (e.g. send SMS, use the module's
00034  *      file system, etc.) while the connection is up.
00035  *
00036  *  2.  The UbloxATCellularInterfaceExt class can
00037  *      be used to perform very simple HTTP and FTP
00038  *      operations using the modem's on-board clients.
00039  *
00040  *  3.  LWIP is not required (and hence RAM is saved).
00041  *
00042  *  The disadvantage is that some additional parsing
00043  *  (at the AT interface) has to go on in order to exchange
00044  *  IP packets, so this is less efficient under heavy loads.
00045  *  Also TCP Server and getting/setting of socket options is
00046  *  currently not supported.
00047  */
00048 
00049 // Forward declaration
00050 class NetworkStack;
00051 
00052 /*
00053  * NOTE: order is important in the inheritance below!  PAL takes this class
00054  * and casts it to CellularInterface and so CellularInterface has to be first
00055  * in the last for that to work.
00056  */
00057 
00058 /** UbloxATCellularInterface class.
00059  *
00060  *  This class implements the network stack interface into the cellular
00061  *  modems on the C030 and C027 boards for 2G/3G/4G modules using
00062  *  the IP stack running on the cellular module.
00063  */
00064 class UbloxATCellularInterfaceN2xx : public CellularBase, public NetworkStack, virtual public UbloxCellularBaseN2xx  {
00065 
00066 public:
00067 
00068     /** Constructor.
00069      *
00070      * @param tx       the UART TX data pin to which the modem is attached.
00071      * @param rx       the UART RX data pin to which the modem is attached.
00072      * @param baud     the UART baud rate.
00073      * @param debug_on true to switch AT interface debug on, otherwise false.
00074      */
00075      UbloxATCellularInterfaceN2xx(PinName tx = MDMTXD,
00076                               PinName rx = MDMRXD,
00077                               int baud = MBED_CONF_UBLOX_CELL_N2XX_BAUD_RATE,
00078                               bool debug_on = false);
00079 
00080      /* Destructor.
00081       */
00082      virtual ~UbloxATCellularInterfaceN2xx();
00083 
00084     /** The amount of extra space needed in terms of AT interface
00085      * characters to get a chunk of user data (i.e. one UDP packet
00086      * or a portion of a TCP packet) across the AT interface.
00087      */
00088     #define AT_PACKET_OVERHEAD 77
00089 
00090     /** The profile to use (on board the modem).
00091      */
00092     #define PROFILE "0"
00093 
00094     /** Translates a host name to an IP address with specific IP version.
00095      *
00096      *  The host name may be either a domain name or an IP address. If the
00097      *  host name is an IP address, no network transactions will be performed.
00098      *
00099      *  If no stack-specific DNS resolution is provided, the host name
00100      *  will be resolved using a UDP socket on the stack.
00101      *
00102      *  @param host     Host name to resolve.
00103      *  @param address  Destination for the host SocketAddress.
00104      *  @param version  IP version of address to resolve, NSAPI_UNSPEC indicates
00105      *                  version is chosen by the stack (defaults to NSAPI_UNSPEC).
00106      *  @return         0 on success, negative error code on failure.
00107      */
00108     virtual nsapi_error_t gethostbyname(const char *host,
00109                                         SocketAddress *address,
00110                                         nsapi_version_t version = NSAPI_UNSPEC);
00111 
00112     /** Set the authentication scheme.
00113      *
00114      *  @param auth      The authentication scheme, chose from
00115      *                   NSAPI_SECURITY_NONE, NSAPI_SECURITY_PAP,
00116      *                   NSAPI_SECURITY_CHAP or NSAPI_SECURITY_UNKNOWN;
00117      *                   use NSAPI_SECURITY_UNKNOWN to try all of none,
00118      *                   PAP and CHAP.
00119      */
00120     virtual void set_authentication(nsapi_security_t auth);
00121 
00122     /** Set the cellular network credentials.
00123      *
00124      *  Please check documentation of connect() for default behaviour of APN settings.
00125      *
00126      *  @param apn      Access point name.
00127      *  @param uname    Optionally, user name.
00128      *  @param pwd      Optionally, password.
00129      */
00130     virtual void set_credentials(const char *apn, const char *uname = 0,
00131                                  const char *pwd = 0);
00132 
00133     /** Set the PIN code for the SIM card.
00134      *
00135      *  @param sim_pin      PIN for the SIM card.
00136      */
00137     virtual void set_sim_pin(const char *sim_pin);
00138     
00139     /** Set the local listen port when opening a UDP socket
00140      * 
00141      */     
00142     void set_LocalListenPort(int port);
00143     
00144     /** 
00145      * Turns on the modem and reads the module information     
00146      */
00147     bool initialise();
00148 
00149     /** Connect to the cellular network and start the interface.
00150      *
00151      *  Attempts to connect to a cellular network.  Note: if initialise() has
00152      *  not been called beforehand, connect() will call it first.
00153      *
00154      *  @param sim_pin     PIN for the SIM card.
00155      *  @param apn         Optionally, access point name.
00156      *  @param uname       Optionally, user name.
00157      *  @param pwd         Optionally, password.
00158      *  @return            NSAPI_ERROR_OK on success, or negative error code on failure.
00159      */
00160     virtual nsapi_error_t connect(const char *sim_pin, const char *apn = 0,
00161                                   const char *uname = 0, const char *pwd = 0);
00162 
00163     /** Attempt to connect to the cellular network.
00164      *
00165      *  Brings up the network interface. Connects to the cellular radio
00166      *  network and then brings up IP stack on the cellular modem to be used
00167      *  indirectly via AT commands, rather than LWIP.  Note: if init() has
00168      *  not been called beforehand, connect() will call it first.
00169      *  NOTE: even a failed attempt to connect will cause the modem to remain
00170      *  powered up.  To power it down, call deinit().
00171      *
00172      *  For APN setup, default behaviour is to use 'internet' as APN string
00173      *  and assuming no authentication is required, i.e., user name and password
00174      *  are not set. Optionally, a database lookup can be requested by turning
00175      *  on the APN database lookup feature. The APN database is by no means
00176      *  exhaustive (feel free to submit a pull request with additional values).
00177      *  It contains a short list of some public APNs with publicly available
00178      *  user names and passwords (if required) in some particular countries only.
00179      *  Lookup is done using IMSI (International mobile subscriber identifier).
00180      *
00181      *  The preferred method is to setup APN using 'set_credentials()' API.
00182      *
00183      *  If you find that the AT interface returns "CONNECT" but shortly afterwards
00184      *  drops the connection then 99% of the time this will be because the APN
00185      *  is incorrect.
00186      *
00187      *  @return            0 on success, negative error code on failure.
00188      */
00189     virtual nsapi_error_t connect();
00190 
00191     /** Attempt to disconnect from the network.
00192      *
00193      *  Brings down the network interface.
00194      *  Does not bring down the Radio network.
00195      *
00196      *  @return            0 on success, negative error code on failure.
00197      */
00198     virtual nsapi_error_t disconnect();
00199 
00200     /** Adds or removes a SIM facility lock.
00201      *
00202      * Can be used to enable or disable SIM PIN check at device startup.
00203      *
00204      * @param set          Can be set to true if the SIM PIN check is supposed
00205      *                     to be enabled and vice versa.
00206      * @param immediate    If true, change the SIM PIN now, else set a flag
00207      *                     and make the change only when connect() is called.
00208      *                     If this is true and init() has not been called previously,
00209      *                     it will be called first.
00210      * @param sim_pin      The current SIM PIN, must be a const.  If this is not
00211      *                     provided, the SIM PIN must have previously been set by a
00212      *                     call to set_sim_pin().
00213      * @return             0 on success, negative error code on failure.
00214      */
00215     nsapi_error_t set_sim_pin_check(bool set, bool immediate = false,
00216                                     const char *sim_pin = NULL);
00217 
00218     /** Change the PIN for the SIM card.
00219      *
00220      * Provide the new PIN for your SIM card with this API.  It is ONLY possible to
00221      * change the SIM PIN when SIM PIN checking is ENABLED.
00222      *
00223      * @param new_pin    New PIN to be used in string format, must be a const.
00224      * @param immediate  If true, change the SIM PIN now, else set a flag
00225      *                   and make the change only when connect() is called.
00226      *                   If this is true and init() has not been called previously,
00227      *                   it will be called first.
00228      * @param old_pin    Old PIN, must be a const.  If this is not provided, the SIM PIN
00229      *                   must have previously been set by a call to set_sim_pin().
00230      * @return           0 on success, negative error code on failure.
00231      */
00232     nsapi_error_t set_new_sim_pin(const char *new_pin, bool immediate = false,
00233                                   const char *old_pin = NULL);
00234 
00235     /** Check if the connection is currently established or not.
00236      *
00237      * @return          True if connected to a data network, otherwise false.
00238      */
00239     virtual bool is_connected();
00240 
00241     /** Get the local IP address
00242      *
00243      *  @return         Null-terminated representation of the local IP address
00244      *                  or null if no IP address has been received.
00245      */
00246     virtual const char *get_ip_address();
00247 
00248     /** Get the local network mask.
00249      *
00250      *  @return         Null-terminated representation of the local network mask
00251      *                  or null if no network mask has been received.
00252      */
00253     virtual const char *get_netmask();
00254 
00255     /** Get the local gateways.
00256      *
00257      *  @return         Null-terminated representation of the local gateway
00258      *                  or null if no network mask has been received.
00259      */
00260     virtual const char *get_gateway();
00261 
00262     /** Set the plmn. PLMN controls to what network device registers.
00263      *
00264      *  @param plmn     user to force what network to register.
00265      */
00266     virtual void set_plmn(const char *plmn);
00267 
00268     /** Call back in case connection is lost.
00269      *
00270      * @param cb     The function to call.
00271      */
00272     void connection_status_cb(Callback<void(nsapi_error_t)> cb);
00273 
00274 protected:
00275 
00276     /** Socket "unused" value.
00277      */
00278     #define SOCKET_UNUSED -1
00279 
00280     /** Socket timeout value in milliseconds.
00281      * Note: the sockets layer above will retry the
00282      * call to the functions here when they return NSAPI_ERROR_WOULD_BLOCK
00283      * and the user has set a larger timeout or full blocking.
00284      */
00285     #define SOCKET_TIMEOUT 1000
00286 
00287     /** The maximum number of bytes in a packet that can be written
00288      * to the AT interface in one go.
00289      */
00290     #define MAX_WRITE_SIZE_N2XX 512
00291 
00292     /** The maximum number of bytes in a packet that can be read from
00293      * from the AT interface in one go.
00294      */
00295     #define MAX_READ_SIZE_N2XX 512
00296 
00297     /** Management structure for sockets.
00298      */
00299     typedef struct {
00300         int modem_handle;  //!< The modem's handle for the socket.
00301         volatile nsapi_size_t pending; //!< The number of received bytes pending.
00302         void (*callback)(void *); //!< A callback for events.
00303         void *data; //!< A data pointer that must be passed to the callback.
00304     } SockCtrl;
00305 
00306     /** Sockets storage.
00307      */
00308     SockCtrl _sockets[7];
00309 
00310     /** Storage for a single IP address.
00311      */
00312     char *_ip;
00313 
00314     /** The APN to use.
00315      */
00316     const char *_apn;
00317 
00318     /** The user name to use.
00319      */
00320     const char *_uname;
00321 
00322     /** The password to use.
00323      */
00324     const char *_pwd;
00325 
00326     /** The type of authentication to use.
00327      */
00328     nsapi_security_t _auth;
00329 
00330     /** Get the next set of credentials from the database.
00331      */
00332     virtual void get_next_credentials(const char * config);
00333 
00334     /** Provide access to the NetworkStack object
00335      *
00336      *  @return        The underlying NetworkStack object.
00337      */
00338     virtual NetworkStack *get_stack();
00339 
00340 protected:
00341 
00342     /** Open a socket.
00343      *
00344      *  Creates a network socket and stores it in the specified handle.
00345      *  The handle must be passed to following calls on the socket.
00346      *
00347      *  @param handle   Destination for the handle to a newly created socket.
00348      *  @param proto    Protocol of socket to open, NSAPI_TCP or NSAPI_UDP.
00349      *  @return         0 on success, negative error code on failure.
00350      */
00351     virtual nsapi_error_t socket_open(nsapi_socket_t *handle,
00352                                       nsapi_protocol_t proto);
00353 
00354     /** Close a socket.
00355      *
00356      *  Closes any open connection and deallocates any memory associated
00357      *  with the socket.
00358      *
00359      *  @param handle   Socket handle.
00360      *  @return         0 on success, negative error code on failure.
00361      */
00362     virtual nsapi_error_t socket_close(nsapi_socket_t handle);
00363 
00364     /** Bind a specific port to a socket.
00365      *
00366      *  Binding a socket specifies port on which to receive
00367      *  data. The IP address is ignored.  Note that binding
00368      *  a socket involves closing it and reopening and so the
00369      *  bind operation should be carried out before any others.
00370      *
00371      *  @param handle   Socket handle.
00372      *  @param address  Local address to bind (of which only the port is used).
00373      *  @return         0 on success, negative error code on failure.
00374      */
00375     virtual nsapi_error_t socket_bind(nsapi_socket_t handle,
00376                                       const SocketAddress &address);
00377 
00378     /** Connects TCP socket to a remote host.
00379      *
00380      *  Initiates a connection to a remote server specified by the
00381      *  indicated address.
00382      *
00383      *  @param handle   Socket handle.
00384      *  @param address  The SocketAddress of the remote host.
00385      *  @return         0 on success, negative error code on failure.
00386      */
00387     virtual nsapi_error_t socket_connect(nsapi_socket_t handle,
00388                                          const SocketAddress &address);
00389 
00390     /** Send data over a TCP socket.
00391      *
00392      *  The socket must be connected to a remote host. Returns the number of
00393      *  bytes sent from the buffer.  This class sets no upper buffer limit on
00394      *  buffer size and the maximum packet size is not connected with the
00395      *  platform.buffered-serial-txbuf-size/platform.buffered-serial-rxbuf-size
00396      *  definitions.
00397      *
00398      *  @param handle   Socket handle.
00399      *  @param data     Buffer of data to send to the host.
00400      *  @param size     Size of the buffer in bytes.
00401      *  @return         Number of sent bytes on success, negative error
00402      *                  code on failure.
00403      */
00404     virtual nsapi_size_or_error_t socket_send(nsapi_socket_t handle,
00405                                               const void *data, nsapi_size_t size);
00406 
00407     /** Send a packet over a UDP socket.
00408      *
00409      *  Sends data to the specified address. Returns the number of bytes
00410      *  sent from the buffer.
00411      *
00412      *  PACKET SIZES: the maximum packet size that can be sent in a single
00413      *  UDP packet is limited by the configuration value
00414      *  platform.buffered-serial-txbuf-size (defaults to 256).
00415      *  The maximum UDP packet size is:
00416      *
00417      *  platform.buffered-serial-txbuf-size - AT_PACKET_OVERHEAD
00418      *
00419      *  ...with a limit of 1024 bytes (at the AT interface). So, to allow sending
00420      *  of a 1024 byte UDP packet, edit your mbed_app.json to add a target override
00421      *  setting platform.buffered-serial-txbuf-size to 1101.  However, for
00422      *  UDP packets, 508 bytes is considered a more realistic size, taking into
00423      *  account fragmentation sizes over the public internet, which leads to a
00424      *  platform.buffered-serial-txbuf-size/platform.buffered-serial-rxbuf-size
00425      *  setting of 585.
00426      *
00427      *  If size is larger than this limit, the data will be split across separate
00428      *  UDP packets.
00429      *
00430      *  @param handle   Socket handle.
00431      *  @param address  The SocketAddress of the remote host.
00432      *  @param data     Buffer of data to send to the host.
00433      *  @param size     Size of the buffer in bytes.
00434      *  @return         Number of sent bytes on success, negative error
00435      *                  code on failure.
00436      */
00437     virtual nsapi_size_or_error_t socket_sendto(nsapi_socket_t handle,
00438                                                 const SocketAddress &address,
00439                                                 const void *data,
00440                                                 nsapi_size_t size);
00441 
00442     /** Receive data over a TCP socket.
00443      *
00444      *  The socket must be connected to a remote host. Returns the number of
00445      *  bytes received into the buffer.  This class sets no upper limit on the
00446      *  buffer size and the maximum packet size is not connected with the
00447      *  platform.buffered-serial-txbuf-size/platform.buffered-serial-rxbuf-size
00448      *  definitions.
00449      *
00450      *  @param handle   Socket handle.
00451      *  @param data     Destination buffer for data received from the host.
00452      *  @param size     Size of the buffer in bytes.
00453      *  @return         Number of received bytes on success, negative error
00454      *                  code on failure.
00455      */
00456     virtual nsapi_size_or_error_t socket_recv(nsapi_socket_t handle,
00457                                               void *data, nsapi_size_t size);
00458 
00459     /** Receive a packet over a UDP socket.
00460      *
00461      *  Receives data and stores the source address in address if address
00462      *  is not NULL. Returns the number of bytes received into the buffer.
00463      *
00464      *  PACKET SIZES: the maximum packet size that can be retrieved in a
00465      *  single call to this method is limited by the configuration value
00466      *  platform.buffered-serial-rxbuf-size (default 256).  The maximum
00467      *  UDP packet size is:
00468      *
00469      *  platform.buffered-serial-rxbuf-size - AT_PACKET_OVERHEAD
00470      *
00471      *  ...with a limit of 1024 (at the AT interface). So to allow reception of a
00472      *  1024 byte UDP packet in a single call, edit your mbed_app.json to add a
00473      *  target override setting platform.buffered-serial-rxbuf-size to 1101.
00474      *
00475      *  If the received packet is larger than this limit, any remainder will
00476      *  be returned in subsequent calls to this method.  Once a single UDP
00477      *  packet has been received, this method will return.
00478      *
00479      *  @param handle   Socket handle.
00480      *  @param address  Destination for the source address or NULL.
00481      *  @param data     Destination buffer for data received from the host.
00482      *  @param size     Size of the buffer in bytes.
00483      *  @return         Number of received bytes on success, negative error
00484      *                  code on failure.
00485      */
00486     virtual nsapi_size_or_error_t socket_recvfrom(nsapi_socket_t handle,
00487                                                   SocketAddress *address,
00488                                                   void *data, nsapi_size_t size);
00489 
00490     /** Register a callback on state change of the socket.
00491      *
00492      *  The specified callback will be called on state changes such as when
00493      *  the socket can recv/send/accept successfully and on when an error
00494      *  occurs. The callback may also be called spuriously without reason.
00495      *
00496      *  The callback may be called in an interrupt context and should not
00497      *  perform expensive operations such as recv/send calls.
00498      *
00499      *  @param handle   Socket handle.
00500      *  @param callback Function to call on state change.
00501      *  @param data     Argument to pass to callback.
00502      */
00503     virtual void socket_attach(nsapi_socket_t handle, void (*callback)(void *),
00504                                void *data);
00505 
00506     /** Listen for connections on a TCP socket.
00507      *
00508      *  Marks the socket as a passive socket that can be used to accept
00509      *  incoming connections.
00510      *
00511      *  @param handle   Socket handle.
00512      *  @param backlog  Number of pending connections that can be queued
00513      *                  simultaneously, defaults to 1.
00514      *  @return         0 on success, negative error code on failure.
00515      */
00516     virtual nsapi_error_t socket_listen(nsapi_socket_t handle, int backlog);
00517 
00518     /** Accepts a connection on a TCP socket.
00519      *
00520      *  The server socket must be bound and set to listen for connections.
00521      *  On a new connection, creates a network socket and stores it in the
00522      *  specified handle. The handle must be passed to following calls on
00523      *  the socket.
00524      *
00525      *  A stack may have a finite number of sockets, in this case
00526      *  NSAPI_ERROR_NO_SOCKET is returned if no socket is available.
00527      *
00528      *  This call is non-blocking. If accept would block,
00529      *  NSAPI_ERROR_WOULD_BLOCK is returned immediately.
00530      *
00531      *  @param server   Socket handle to server to accept from.
00532      *  @param handle   Destination for a handle to the newly created socket.
00533      *  @param address  Destination for the remote address or NULL.
00534      *  @return         0 on success, negative error code on failure.
00535      */
00536     virtual nsapi_error_t socket_accept(nsapi_socket_t server,
00537                                         nsapi_socket_t *handle,
00538                                         SocketAddress *address = 0);
00539 
00540     /**  Set stack-specific socket options.
00541      *
00542      *  The setsockopt allow an application to pass stack-specific hints
00543      *  to the underlying stack. For unsupported options,
00544      *  NSAPI_ERROR_UNSUPPORTED is returned and the socket is unmodified.
00545      *
00546      *  @param handle   Socket handle.
00547      *  @param level    Stack-specific protocol level.
00548      *  @param optname  Stack-specific option identifier.
00549      *  @param optval   Option value.
00550      *  @param optlen   Length of the option value.
00551      *  @return         0 on success, negative error code on failure.
00552      */
00553     virtual nsapi_error_t setsockopt(nsapi_socket_t handle, int level,
00554                                      int optname, const void *optval,
00555                                      unsigned optlen);
00556 
00557     /**  Get stack-specific socket options.
00558      *
00559      *  The getstackopt allow an application to retrieve stack-specific hints
00560      *  from the underlying stack. For unsupported options,
00561      *  NSAPI_ERROR_UNSUPPORTED is returned and optval is unmodified.
00562      *
00563      *  @param handle   Socket handle.
00564      *  @param level    Stack-specific protocol level.
00565      *  @param optname  Stack-specific option identifier.
00566      *  @param optval   Destination for option value.
00567      *  @param optlen   Length of the option value.
00568      *  @return         0 on success, negative error code on failure.
00569      */
00570     virtual nsapi_error_t getsockopt(nsapi_socket_t handle, int level,
00571                                      int optname, void *optval,
00572                                      unsigned *optlen);
00573 
00574 private:
00575 
00576     // u_ added to namespace us somewhat as this darned macro
00577     // is defined by everyone and their dog
00578     #define u_stringify(a) str(a)
00579     #define str(a) #a
00580 
00581     int _localListenPort;
00582     
00583     bool _sim_pin_check_change_pending;
00584     bool _sim_pin_check_change_pending_enabled_value;
00585     bool _sim_pin_change_pending;
00586     const char *_sim_pin_change_pending_new_pin_value;
00587     Thread event_thread;
00588     void handle_event();
00589     SockCtrl * find_socket(int modem_handle = SOCKET_UNUSED);
00590     void clear_socket(SockCtrl * socket);
00591     bool check_socket(SockCtrl * socket);
00592     
00593     nsapi_size_or_error_t receivefrom(int socketId, SocketAddress *address, int length, char *buf);
00594     nsapi_size_or_error_t sendto(SockCtrl *socket, const SocketAddress &address, const char *buf, int size);
00595     bool sendATChopped(const char *);
00596     
00597     char hex_char(char c);
00598     int hex_to_bin(const char* s, char * buff, int length);
00599     void bin_to_hex(const char *buff, unsigned int length, char *output);
00600     
00601     Callback<void(nsapi_error_t)> _connection_status_cb;
00602     void NSONMI_URC();    
00603 };
00604 
00605 #endif // _UBLOX_AT_CELLULAR_INTERFACE_
00606