/* Called by LAPB to transmit data via physical connection */
void lapb_transmit_data(struct lapb_cs * lapb, char *data, int data_size, int extra_before, int extra_after) {
(void)lapb;
(void)extra_before;
(void)extra_after;
if (!is_server_accepted()) return;
//lapb_debug(lapb, 0, "[LAPB] data_transmit is called");
_uchar buffer[1024];
buffer[0] = 0x7E; /* Open flag */
buffer[1] = 0x7E; /* Open flag */
memcpy(&buffer[2], data, data_size);
buffer[data_size + 2] = 0; /* Good FCS */
buffer[data_size + 3] = 0; /* Good FCS */
buffer[data_size + 4] = 0x7E; /* Close flag */
buffer[data_size + 5] = 0x7E; /* Close flag */
int n = send(tcp_client_socket(), buffer, data_size + 6, MSG_NOSIGNAL);
if (n < 0)
lapb_debug(0, "[LAPB] ERROR writing to socket, %s", strerror(errno));
}
/* Called by LAPB to transmit data via physical connection */
void transmit_data(struct lapb_cs * lapb, char *data, int data_size, int extra_before, int extra_after) {
(void)lapb;
(void)extra_before;
(void)extra_after;
if (!is_server_accepted()) return;
//debug(lapb, 0, "[LAPB] data_transmit is called");
_uchar buffer[1024];
buffer[0] = 0x7E; /* Open flag */
buffer[1] = 0x7E; /* Open flag */
memcpy(&buffer[2], data, data_size);
if (error_type == 1) { /* Bad FCS (for I frames) */
_uchar i_frame = ~(buffer[3] & 0x01);
if (i_frame && (error_counter == 0)) {
buffer[data_size + 2] = 1; /* Bad FCS */
buffer[data_size + 3] = 1; /* Bad FCS */
} else {
buffer[data_size + 2] = 0; /* Good FCS */
buffer[data_size + 3] = 0; /* Good FCS */
};
} else if (error_type == 2) { /* Bad N(R) (for I or S frames) */
_uchar if_nr_present = buffer[3];
if_nr_present = if_nr_present & 0x03;
if ((if_nr_present != 0x03) && (error_counter == 0))
buffer[3] |= 0xE0; /* Bad N(R) */
buffer[data_size + 2] = 0; /* Good FCS */
buffer[data_size + 3] = 0; /* Good FCS */
} else {
buffer[data_size + 2] = 0; /* Good FCS */
buffer[data_size + 3] = 0; /* Good FCS */
};
buffer[data_size + 4] = 0x7E; /* Close flag */
buffer[data_size + 5] = 0x7E; /* Close flag */
int n = send(tcp_client_socket(), buffer, data_size + 6, MSG_NOSIGNAL);
if (n < 0)
lapb_debug(0, "[LAPB] ERROR writing to socket, %s", strerror(errno));
}
void *
client_thread (void * param)
{
int n, ret, fd, port, sknum = 0;
char buf[9216];
unsigned long xmitted = 0;
D ("Start to connect");
/* create tcp client sockets for each flow */
for (sknum = 0; sknum < tcpgen.flow_num; sknum++) {
if (!tcpgen.randomized)
port = 0;
else
port = RANDOM_PORT ();
fd = tcp_client_socket (tcpgen.dst, tcpgen.src,
TCPGEN_PORT, port);
if (!fd) {
goto err;
}
tcpgen.client_sock[sknum] = fd;
}
/* initalize flow distribution */
switch (tcpgen.flow_dist) {
case FLOWDIST_SAME :
flow_dist_init_same ();
break;
case FLOWDIST_RANDOM :
flow_dist_init_random ();
break;
case FLOWDIST_POWER :
flow_dist_init_power ();
break;
default :
D ("invalid flow distribution pattern");
goto err;
}
/* send packets */
while (1) {
for (n = 0; n < tcpgen.socklistlen; n++) {
ret = write (tcpgen.socklist[n], buf, tcpgen.data_len);
if (ret < 0) {
D ("failed to write %d byte to socket %d",
tcpgen.data_len, tcpgen.socklist[n]);
goto err;
}
if (tcpgen.verbose)
D ("write %d bytes to socket %d", ret,
tcpgen.socklist[n]);
if (tcpgen.interval)
usleep (tcpgen.interval);
xmitted++;
if (tcpgen.count && tcpgen.count < xmitted)
goto err;
}
}
err:
for (n = 0; n < sknum; n++)
close (tcpgen.client_sock[n]);
return NULL;
}