// read_cb: a TCP connection is readable so read the bytes that are on
// it and pass them to OpenSSL
void read_cb(uv_stream_t *s, ssize_t nread, const uv_buf_t *buf)
{
connection_state *state = (connection_state *)s->data;
if (nread > 0) {
// If there's data to read then pass it to OpenSSL via the BIO
// TODO: check return value
BIO_write(state->read_bio, buf->base, nread);
}
if ((nread == UV_EOF) || (nread < 0)) {
connection_terminate(state->tcp);
} else {
if (do_ssl(state)) {
write_queued_messages(state);
flush_write(state);
} else {
connection_terminate(state->tcp);
}
}
// Buffer was previously allocated by us in a call to
// allocate_cb. libuv will not reuse so we must free.
if (buf) {
free(buf->base);
}
}
int telnet_run(tcp_connection_t *conn)
{
size_t bytes = 0;
while(1)
{
/* Receive from socket */
bytes = recv(conn->tcp_sock, buffer, 2048, 0);
if(0 == bytes)
{
printf("Remote host closed connection.\n");
return connection_close(conn);
}
if(0 > bytes)
{
fprintf(stderr, "error while receiving from remote host!\n");
return -1;
}
/********************************************
* Very sophisticated business logic *
********************************************/
if(0 == strncmp(buffer, "quit", 4))
{
return connection_close(conn);
}
else if(0 == strncmp(buffer, "halt", 4))
{
return connection_terminate(conn);
}
else
{
memcpy(buffer, "Unknown command!\n", 17);
bytes = 17;
}
/********************************************/
/* Answer on socket */
bytes = send(conn->tcp_sock, buffer, bytes, 0);
if(0 >= bytes)
{
fprintf(stderr, "error while sending to remote host!\n");
return -1;
}
memset(buffer, 0, 2048);
}
return 0;
}
