smsc_oisd.c

The Kannel Open Source WAP and SMS gateway works as both an SMS gateway, for implementing keyword b

     *             the recipient in interpreting the SM.
     *                   z = reply path
     *                   y = user data header indicator
     *                   x = reserved
     */

    /*
     * Destination addr. and Originating addr. w/o TOA
     */

    /* Destination addr. length */
    dest_len = octstr_get_char(request->data, 10);

    /* Destination addr. */
    msg->sms.receiver = octstr_copy(request->data, 11+2, dest_len-2);

    /* Originating addr. length */
    origin_len = octstr_get_char(request->data, 11+dest_len+4);

    /* Originating addr. */
    msg->sms.sender = octstr_copy(request->data, 11+dest_len+5+2, origin_len-2);

    DCS = octstr_get_char(request->data, 11+dest_len+5+origin_len);
    if (!dcs_to_fields(&msg, DCS)) {
        /* XXX: Should reject this message ? */
        debug("bb.sms.oisd", 0, "OISD[%s]: Invalid DCS",
              octstr_get_cstr(conn->id));
        dcs_to_fields(&msg, 0);
    }

    add_info = octstr_get_char(request->data,11+dest_len+5+origin_len+2);

    msglen7 = octstr_get_char(request->data, 11+dest_len+5+origin_len+3);
    msglen8 = octstr_get_char(request->data, 11+dest_len+5+origin_len+4);

    msg->sms.rpi = add_info & 0x01;

    debug("bb.sms.oisd", 0,
          "OISD[%s]: received DCS=%02X, add_info=%d, msglen7=%d, msglen8=%d, rpi=%ld",
          octstr_get_cstr(conn->id),
          DCS, add_info, msglen7, msglen8, msg->sms.rpi);

    if (msg->sms.coding == DC_7BIT) {
        msg->sms.msgdata =
            oisd_expand_gsm7(octstr_copy(request->data,
                                         11+dest_len+5+origin_len+5,
                                         msglen7));
            debug("bb.sms.oisd", 0, "OISD[%s]: received raw8=%s ",
                  octstr_get_cstr(conn->id),
                  octstr_get_cstr(msg->sms.msgdata));
        if (add_info & 0x02) {
            warning(0, "OISD[%s]: 7-bit UDH ?",
                    octstr_get_cstr(conn->id));
        } else {
            charset_gsm_to_latin1(msg->sms.msgdata);
            debug("bb.sms.oisd", 0, "OISD[%s]: received latin1=%s",
                  octstr_get_cstr(conn->id),
                  octstr_get_cstr(msg->sms.msgdata));
        }
    } else {
        /* 0xf4, 0xf5, 0xf6, 0xf7; 8bit to disp, mem, sim or term */
        if (add_info & 0x02) {
            udh_len = octstr_get_char(request->data,
                                      11+dest_len+5+origin_len+5)+1;
            msg->sms.msgdata =
                octstr_copy(request->data,
                            11+dest_len+5+origin_len+5+udh_len,
                            msglen8);
            msg->sms.udhdata =
                octstr_copy(request->data,
                            11+dest_len+5+origin_len+5,
                            udh_len);
        } else {
            msg->sms.msgdata =
                octstr_copy(request->data,
                            11+dest_len+5+origin_len+5,
                            msglen8);
        }
    }

    /* Code elsewhere in the gateway always expects the sender and
     * receiver fields to be filled, so we discard messages that
     * lack them.  If they should not be discarded, then the code
     * handling sms messages should be reviewed.  -- RB */
    if (!(msg->sms.receiver) || octstr_len(msg->sms.receiver) == 0) {
        info(0, "OISD[%s]: Got SMS without receiver, discarding.",
             octstr_get_cstr(conn->id));
        goto error;
    }

    if (!(msg->sms.sender) || octstr_len(msg->sms.sender) == 0) {
        info(0, "OISD[%s]: Got SMS without sender, discarding.",
              octstr_get_cstr(conn->id));
        goto error;
    }

    if ((!(msg->sms.msgdata) || octstr_len(msg->sms.msgdata) == 0)
        && (!(msg->sms.udhdata) || octstr_len(msg->sms.udhdata) == 0)) {
        info(0, "OISD[%s]: Got empty SMS, ignoring.",
              octstr_get_cstr(conn->id));
        goto error;
    }

    return msg;

error:
    msg_destroy(msg);
    return NULL;
}

/* Deal with a request from the OISD server, and acknowledge it. */
static void oisd_handle_request(struct packet *request, SMSCConn *conn)
{
    PrivData *pdata = conn->data;
    Msg *msg = NULL;

    if (request->operation == STATUS_REPORT) {
        msg = oisd_accept_delivery_report_message(request, conn);
        if (msg)
            list_append(pdata->received, msg);
    } else if (request->operation == DELIVER_SM) {
        msg = oisd_accept_message(request, conn);
        if (msg)
            list_append(pdata->received, msg);
    }

    oisd_send_response(request, pdata);
}

/* Send a request and wait for the ack.  If the other side responds with
 * an error code, attempt to correct and retry.
 * If other packets arrive while we wait for the ack, handle them.
 *
 * Return -1 if the SMSC refused the request.  Return -2 for other
 * errors, such as being unable to send the request at all.  If the
 * function returns -2, the caller would do well to try to reopen the
 * connection.
 *
 * The SMSCenter must be already open.
 */
static int oisd_request(struct packet *request, SMSCConn *conn, Octstr **ts)
{
    PrivData *pdata = conn->data;
    int ret;
    struct packet *reply = NULL;
    int errorcode;
    int tries = 0;
    Octstr *request_name;

    gw_assert(pdata != NULL);
    gw_assert(request != NULL);
    gw_assert(operation_can_send(request->operation));

    if (pdata->socket < 0) {
        warning(0, "OISD[%s]: oisd_request: socket not open.",
                octstr_get_cstr(conn->id));
        return -2;
    }

    packet_set_data_size(request);

retransmit:
    packet_set_send_sequence(request, pdata);

    request_name = operation_name(request->operation);
    debug("bb.sms.oisd", 0, "OISD[%s]: sending %s request",
          octstr_get_cstr(conn->id),
          octstr_get_cstr(request_name));
    octstr_destroy(request_name);
    if (request->operation != RETRIEVE_REQUEST)
        octstr_dump(request->data, 0);

    ret = octstr_write_to_socket(pdata->socket, request->data);
    if (ret < 0)
        goto io_error;

next_reply:
    packet_destroy(reply);  /* destroy old, if any */
    reply = oisd_get_packet(pdata, ts);
    if (!reply)
        goto io_error;

    /* The server sent us a request.  Handle it, then wait for
     * a new reply. */
    if (reply->operation < RESPONSE) {
        oisd_handle_request(reply, conn);
        goto next_reply;
    }

    if (reply->opref != request->opref) {
        /* We got a response to a different request number than
         * what we send.  Strange. */
        warning(0, "OISD[%s]: response had unexpected sequence number; ignoring.",
                octstr_get_cstr(conn->id));
        goto next_reply;
    }

    if (reply->operation != request->operation + RESPONSE) {
        /* We got a response that didn't match our request */
        Octstr *request_name = operation_name(request->operation);
        Octstr *reply_name = operation_name(reply->operation);
        warning(0, "OISD[%s]: %s request got a %s",
                octstr_get_cstr(conn->id),
                octstr_get_cstr(request_name),
                octstr_get_cstr(reply_name));

        octstr_destroy(request_name);
        octstr_destroy(reply_name);
        octstr_dump(reply->data, 0);
        goto retry;
    }

    errorcode = octstr_get_char(reply->data, 10); /* Result */

    if (errorcode > 0)
        goto error;

    /* The reply passed all the checks... looks like the SMSC accepted
     * our request! */
    packet_destroy(reply);
    return 0;

io_error:
    packet_destroy(reply);
    return -2;

error:
    packet_destroy(reply);
    return -1;

retry:
    if (++tries < 3) {
        warning(0, "OISD[%s]: Retransmitting (take %d)",
                octstr_get_cstr(conn->id),
                tries);
        goto retransmit;
    }
    warning(0, "OISD[%s]: Giving up.",
            octstr_get_cstr(conn->id));
    goto io_error;
}

/* Close the SMSC socket without fanfare. */
static void oisd_close_socket(PrivData *pdata)
{
    gw_assert(pdata != NULL);

    if (pdata->socket < 0)
        return;

    if (close(pdata->socket) < 0)
        warning(errno, "OISD[%s]: error closing socket",
                octstr_get_cstr(pdata->conn->id));
    pdata->socket = -1;
}

/*
 * Open a socket to the SMSC, send a login packet, and wait for ack.
 * This may block.  Return 0 for success, or -1 for failure.
 * Make sure the socket is closed before calling this function, otherwise
 * we will leak fd's.
 */
static int oisd_login(SMSCConn *conn)
{
    PrivData *pdata = conn->data;
    struct packet *packet = NULL;

    gw_assert(pdata != NULL);

    if (pdata->socket >= 0) {
        warning(0, "OISD[%s]: login: socket was already open; closing",
                octstr_get_cstr(conn->id));
        oisd_close_socket(pdata);
    }

    pdata->socket = tcpip_connect_to_server(
                        octstr_get_cstr(pdata->host),
                        pdata->port,
                        (conn->our_host ? octstr_get_cstr(conn->our_host) : NULL));
    if (pdata->socket != -1) {
        info(0, "OISD[%s] logged in.",
             octstr_get_cstr(conn->id));
        return 0;
    }
    error(0, "OISD[%s] login failed.",
          octstr_get_cstr(conn->id));
    oisd_close_socket(pdata);
    packet_destroy(packet);
    return -1;
}

static int oisd_send_delivery_request(SMSCConn *conn)
{
    PrivData *pdata = conn->data;
    struct packet *packet = NULL;
    int ret;

    gw_assert(conn != NULL);

    packet = packet_create(RETRIEVE_REQUEST, BOGUS_SEQUENCE);

    gw_assert(octstr_check_range(pdata->my_number, 0,
                                 octstr_len(pdata->my_number),
                                 isphonedigit));
    /* Originating address length */
    octstr_append_char(packet->data,
                       (char) (octstr_len(pdata->my_number) + 2));
    /* TON */
    octstr_append_char(packet->data, 0x42);
    /* NPI */
    octstr_append_char(packet->data, 0x44);
    /* Originating address */
    octstr_append(packet->data, pdata->my_number);
    /* Receive ready flag */
    octstr_append_char(packet->data, 1);
    /* Retrieve order */
    octstr_append_char(packet->data, 0);

    ret = oisd_request(packet, conn, NULL);
    packet_destroy(packet);

    if (ret < 0)
        warning(0, "OISD[%s]: Sending delivery request failed.\n",
                octstr_get_cstr(conn->id));

    return ret;
}

static void oisd_destroy(PrivData *pdata)
{
    int discarded;

    if (pdata == NULL)
        return;

    octstr_destroy(pdata->host);
    octstr_destroy(pdata->inbuffer);
    octstr_destroy(pdata->my_number);

    discarded = list_len(pdata->received);
    if (discarded > 0)
        warning(0, "OISD[%s]: discarded %d received messages",
                octstr_get_cstr(pdata->conn->id),
                discarded);

    list_destroy(pdata->received, msg_destroy_item);
    list_destroy(pdata->outgoing_queue, NULL);
    list_destroy(pdata->stopped, NULL);

    gw_free(pdata);
}

static int oisd_submit_msg(SMSCConn *conn, Msg *msg)
{
    PrivData *pdata = conn->data;
    struct packet *packet;
    Octstr *ts = NULL;
    int ret;

    gw_assert(pdata != NULL);
    debug("bb.sms.oisd", 0, "OISD[%s]: sending message",
          octstr_get_cstr(conn->id));

    packet = packet_encode_message(msg, conn);
    if (!packet) {
        /* This is a protocol error. Does this help? I doubt..
         * But nevermind that.
         */
        bb_smscconn_send_failed(conn, msg,
                SMSCCONN_FAILED_MALFORMED, octstr_create("MALFORMED"));
        return -1;
    }

    ret = oisd_request(packet, conn, &ts);
    if((ret == 0) && (ts) && DLR_IS_SUCCESS_OR_FAIL(msg->sms.dlr_mask) && !pdata->no_dlr) {
        dlr_add(conn->name, ts, msg);
    }
    octstr_destroy(ts);
    packet_destroy(packet);

    if (ret == -1) {
        bb_smscconn_send_failed(conn, msg,
                SMSCCONN_FAILED_REJECTED, octstr_create("REJECTED"));
    }
    else if (ret == -2) {
        oisd_close_socket(pdata);
        bb_smscconn_send_failed(conn, msg, SMSCCONN_FAILED_TEMPORARILY, NULL);
        mutex_lock(conn->flow_mutex);
        conn->status = SMSCCONN_DISCONNECTED;
        mutex_unlock(conn->flow_mutex);
    }
    else {
        bb_smscconn_sent(conn, msg, NULL);
    }

    return ret;
}

static int oisd_receive_msg(SMSCConn *conn, Msg **msg)