smsc_at.c

gateway-1.3.2.tar.gz WAP gw code

long at2_queued_cb(SMSCConn *conn)
{
    long ret;
    PrivAT2data *privdata = conn->data;

    if (conn->status == SMSCCONN_DEAD) /* I'm dead, why would you care ? */
	return -1;

    ret = list_len(privdata->outgoing_queue);

    /* use internal queue as load, maybe something else later */

    conn->load = ret;
    return ret;
}


void at2_start_cb(SMSCConn *conn)
{
    PrivAT2data *privdata = conn->data;

    if (conn->status == SMSCCONN_DISCONNECTED)
        conn->status = SMSCCONN_ACTIVE;
    
    /* in case there are messages in the buffer already */
    gwthread_wakeup(privdata->device_thread);
    debug("smsc.at2", 0, "AT2[%s]: start called", octstr_get_cstr(privdata->name));
}

int at2_add_msg_cb(SMSCConn *conn, Msg *sms)
{
    PrivAT2data *privdata = conn->data;
    Msg *copy;

    copy = msg_duplicate(sms);
    list_produce(privdata->outgoing_queue, copy);
    gwthread_wakeup(privdata->device_thread);
    return 0;
}


int smsc_at2_create(SMSCConn *conn, CfgGroup *cfg)
{
    PrivAT2data	*privdata;
    Octstr *modem_type_string;

    privdata = gw_malloc(sizeof(PrivAT2data));
    privdata->outgoing_queue = list_create();
    privdata->pending_incoming_messages = list_create();

    privdata->configfile = cfg_get_configfile(cfg);

    privdata->device = cfg_get(cfg, octstr_imm("device"));
    if (privdata->device == NULL) {
        error(0, "AT2[-]: 'device' missing in at2 configuration.");
        goto error;
    }

    privdata->name = cfg_get(cfg, octstr_imm("smsc-id"));
    if (privdata->name == NULL) {
        privdata->name = octstr_duplicate(privdata->device);
    }

    privdata->speed = 0;
    cfg_get_integer(&privdata->speed, cfg, octstr_imm("speed"));

    privdata->keepalive = 0;
    cfg_get_integer(&privdata->keepalive, cfg, octstr_imm("keepalive"));

    cfg_get_bool(&privdata->sms_memory_poll_interval, cfg, octstr_imm("sim-buffering"));
    if (privdata->sms_memory_poll_interval) {
        if (privdata->keepalive)
            privdata->sms_memory_poll_interval = privdata->keepalive;
        else
            privdata->sms_memory_poll_interval = AT2_DEFAULT_SMS_POLL_INTERVAL;
    }

    privdata->my_number = cfg_get(cfg, octstr_imm("my-number"));
    privdata->sms_center = cfg_get(cfg, octstr_imm("sms-center"));
    modem_type_string = cfg_get(cfg, octstr_imm("modemtype"));

    privdata->modem = NULL;

    if (modem_type_string != NULL) {
        if (octstr_compare(modem_type_string, octstr_imm("auto")) == 0 ||
            octstr_compare(modem_type_string, octstr_imm("autodetect")) == 0)
            O_DESTROY(modem_type_string);
    }

    if (octstr_len(modem_type_string) == 0) {
        info(0, "AT2[%s]: configuration doesn't show modemtype. will autodetect",
             octstr_get_cstr(privdata->name));
    } else {
        info(0, "AT2[%s]: configuration shows modemtype <%s>",
             octstr_get_cstr(privdata->name),
             octstr_get_cstr(modem_type_string));
        privdata->modem = at2_read_modems(privdata, privdata->configfile,
                                          modem_type_string, 0);
        if (privdata->modem == NULL) {
            info(0, "AT2[%s]: modemtype not found, revert to autodetect",
                 octstr_get_cstr(privdata->name));
        } else {
            info(0, "AT2[%s]: read modem definition for <%s>",
                 octstr_get_cstr(privdata->name),
                 octstr_get_cstr(privdata->modem->name));
        }
        O_DESTROY(modem_type_string);
    }

    privdata->ilb = octstr_create("");
    privdata->fd = -1;
    privdata->lines = NULL;
    privdata->pin = cfg_get(cfg, octstr_imm("pin"));
    privdata->pin_ready = 0;
    privdata->conn = conn;
    privdata->phase2plus = 0;
    privdata->validityperiod = cfg_get(cfg, octstr_imm("validityperiod"));
    if (cfg_get_integer((long*)&privdata->max_error_count, cfg, octstr_imm("max-error-count")) == -1)
        privdata->max_error_count = -1;

    conn->data = privdata;
    conn->name = octstr_format("AT2[%s]", octstr_get_cstr(privdata->name));
    conn->status = SMSCCONN_CONNECTING;

    privdata->shutdown = 0;

    conn->status = SMSCCONN_CONNECTING;
    conn->connect_time = time(NULL);

    if ((privdata->device_thread = gwthread_create(at2_device_thread, conn)) == -1) {
        privdata->shutdown = 1;
        goto error;
    }

    conn->shutdown = at2_shutdown_cb;
    conn->queued = at2_queued_cb;
    conn->start_conn = at2_start_cb;
    conn->send_msg = at2_add_msg_cb;
    return 0;

error:
    error(0, "AT2[%s]: Failed to create at2 smsc connection",
          octstr_len(privdata->name) ? octstr_get_cstr(privdata->name) : "");
    if (privdata != NULL) {
        list_destroy(privdata->outgoing_queue, NULL);
    }
    gw_free(privdata);
    conn->why_killed = SMSCCONN_KILLED_CANNOT_CONNECT;
    conn->status = SMSCCONN_DEAD;
    info(0, "AT2[%s]: exiting", octstr_get_cstr(privdata->name));
    return -1;
}


int at2_pdu_extract(PrivAT2data *privdata, Octstr **pdu, Octstr *line)
{
    Octstr *buffer;
    long len = 0;
    int pos = 0;
    int tmp;

    buffer = octstr_duplicate(line);
    /* find the beginning of a message from the modem*/

    if ((pos = octstr_search(buffer, octstr_imm("+CDS:"), 0)) != -1) 
	pos += 5;
    else {
	if ((pos = octstr_search(buffer, octstr_imm("+CMT:"), 0)) != -1)
	    pos += 5;
	else if ((pos = octstr_search(buffer, octstr_imm("+CMGR:"), 0)) != -1) {
	    /* skip status field in +CMGR response */
	    if ((pos = octstr_search(buffer, octstr_imm(","), pos + 6)) != -1) 
		pos++;
	    else
		goto nomsg;
	} else
	    goto nomsg;

	/* skip the next comma in CMGR and CMT responses */
	tmp = octstr_search(buffer, octstr_imm(","), pos);
	if (! privdata->modem->broken && tmp == -1)
	    goto nomsg;
	if (tmp != -1)
	    pos = tmp + 1;
    }

    /* read the message length */
    pos = octstr_parse_long(&len, buffer, pos, 10);
    if (pos == -1)
        goto nomsg;

    /* skip the spaces and line return */
    while (isspace(octstr_get_char(buffer, pos)))
        pos++;

    /* skip the SMSC address on some modem types */
    if (!privdata->modem->no_smsc) {
        tmp = at2_hexchar(octstr_get_char(buffer, pos)) * 16
              + at2_hexchar(octstr_get_char(buffer, pos + 1));
        if (tmp < 0)
            goto nomsg;
        pos += 2 + tmp * 2;
    }

    /* check if the buffer is long enough to contain the full message */
    if (!privdata->modem->broken && octstr_len(buffer) < len * 2 + pos)
        goto nomsg;

    if (privdata->modem->broken && octstr_len(buffer) < len * 2)
        goto nomsg;

    /* copy the PDU then remove it from the input buffer*/
    *pdu = octstr_copy(buffer, pos, len * 2);

    octstr_destroy(buffer);
    return 1;

nomsg:
    octstr_destroy(buffer);
    return 0;
}


int at2_hexchar(int hexc)
{
    hexc = toupper(hexc) - 48;
    return (hexc > 9) ? hexc - 7 : hexc;
}


Msg *at2_pdu_decode(Octstr *data, PrivAT2data *privdata)
{
    int type;
    Msg *msg = NULL;

    /* Get the PDU type */
    type = octstr_get_char(data, 1) & 3;

    switch (type) {

        case AT_DELIVER_SM:
            msg = at2_pdu_decode_deliver_sm(data, privdata);
            break;
        case AT_STATUS_REPORT_SM:
	    msg = at2_pdu_decode_report_sm(data, privdata);
	    break;

            /* Add other message types here: */

    }

    return msg;
}


Msg *at2_pdu_decode_deliver_sm(Octstr *data, PrivAT2data *privdata)
{
    int len, pos, i, ntype;
    int udhi, dcs, udhlen, pid;
    Octstr *origin = NULL;
    Octstr *udh = NULL;
    Octstr *text = NULL, *tmpstr;
    Octstr *pdu = NULL;
    Msg *message = NULL;
    struct universaltime mtime; /* time structure */
    long stime; /* time in seconds */
    int timezone; /* timezone in 15 minutes jumps from GMT */

    /* 
     * Note: some parts of the PDU are not decoded because they are
     * not needed for the Msg type. 
     */

    /* convert the pdu to binary format for ease of processing */
    pdu = at2_convertpdu(data);

    /* UDH Indicator */
    udhi = (octstr_get_char(pdu, 0) & 64) >> 6;

    /* originating address */
    len = octstr_get_char(pdu, 1);
    if (len > 20) /* maximum valid number of semi-octets in Address-Value field */
        goto msg_error;
    ntype = octstr_get_char(pdu, 2);

    pos = 3;
    if ((ntype & 0xD0) == 0xD0) {
        /* Alphanumeric sender */
        origin = octstr_create("");
        tmpstr = octstr_copy(pdu, 3, len);
        at2_decode7bituncompressed(tmpstr, (((len - 1) * 4 - 3) / 7) + 1, origin, 0);
        octstr_destroy(tmpstr);
        debug("bb.smsc.at2", 0, "AT2[%s]: Alphanumeric sender <%s>", 
              octstr_get_cstr(privdata->name), octstr_get_cstr(origin));
        pos += (len + 1) / 2;
    } else {
        origin = octstr_create("");
        if ((ntype & 0x90) == 0x90) {
            /* International number */
            octstr_append_char(origin, '+');
        }
        for (i = 0; i < len; i += 2, pos++) {
            octstr_append_char(origin, (octstr_get_char(pdu, pos) & 15) + 48);
            if (i + 1 < len)
                octstr_append_char(origin, (octstr_get_char(pdu, pos) >> 4) + 48);
        }
        debug("bb.smsc.at2", 0, "AT2[%s]: Numeric sender %s <%s>", 
              octstr_get_cstr(privdata->name), ((ntype & 0x90) == 0x90 ? "(international)" : ""), 
              octstr_get_cstr(origin));
    }

    if (pos > octstr_len(pdu))
        goto msg_error;

    /* PID */
    pid = octstr_get_char(pdu, pos);
    pos++;

    /* DCS */
    dcs = octstr_get_char(pdu, pos);
    pos++;

    /* get the timestamp */
    mtime.year = swap_nibbles(octstr_get_char(pdu, pos));
    pos++;
    mtime.year += (mtime.year < 70 ? 2000 : 1900);
    mtime.month = swap_nibbles(octstr_get_char(pdu, pos));
    mtime.month--;    
    pos++;
    mtime.day = swap_nibbles(octstr_get_char(pdu, pos));
    pos++;
    mtime.hour = swap_nibbles(octstr_get_char(pdu, pos));
    pos++;
    mtime.minute = swap_nibbles(octstr_get_char(pdu, pos));
    pos++;
    mtime.second = swap_nibbles(octstr_get_char(pdu, pos));
    pos++;

    /* 
     * time zone: 
     *
     * time zone is "swapped nibble", with the MSB as the sign (1 is negative).  
     */
    timezone = swap_nibbles(octstr_get_char(pdu, pos));
    pos++;
    timezone = ((timezone >> 7) ? -1 : 1) * (timezone & 127);
    /* 
     * Ok, that was the time zone as read from the PDU. Now how to interpert it? 
     * All the handsets I tested send the timestamp of their local time and the 
     * timezone as GMT+0. I assume that the timestamp is the handset's local time, 
     * so we need to apply the timezone in reverse to get GM time: 
     */

    /* 
     * time in PDU is handset's local time and timezone is handset's time zone 
     * difference from GMT 
     */
    mtime.hour -= timezone / 4;
    mtime.minute -= 15 * (timezone % 4);

    stime = date_convert_universal(&mtime);

    /* get data length
     * XXX: Is it allowed to have length = 0 ??? (alex)
     */
    len = octstr_get_char(pdu, pos);
    pos++;

    debug("bb.smsc.at2", 0, "AT2[%s]: User data length read as (%d)", octstr_get_cstr(privdata->name), len);

    /* if there is a UDH */
    udhlen = 0;
    if (udhi && len > 0) {
        udhlen = octstr_get_char(pdu, pos);
        pos++;
        if (udhlen + 1 > len)
            goto msg_error;
        udh = octstr_copy(pdu, pos, udhlen);
        pos += udhlen;
        len -= udhlen + 1;
    } else if (len <= 0) /* len < 0 is impossible, but sure is sure */
        udhi = 0;

    debug("bb.smsc.at2", 0, "AT2[%s]: Udh decoding done len=%d udhi=%d udhlen=%d udh='%s'",
          octstr_get_cstr(privdata->name), len, udhi, udhlen, (udh?octstr_get_cstr(udh):""));

    if (pos > octstr_len(pdu) || len < 0)
        goto msg_error;

    /* build the message */
    message = msg_create(sms);
    if (!dcs_to_fields(&message, dcs)) {
        /* XXX Should reject this message? */
        debug("bb.smsc.at2", 0, "AT2[%s]: Invalid DCS",
              octstr_get_cstr(privdata->name));
        dcs_to_fields(&message, 0);
    }