/* Prepare data from inner uIP stack to be sent out to the remote host,
this is fill the IP and UDP headers of the outer stack part. */
void
openvpn_process_out (void)
{
uip_udp_conn = openvpn_conn; /* Change back to OpenVPN connection. */
uint8_t stackno = router_find_stack (&uip_udp_conn->ripaddr);
if (stackno == STACK_OPENVPN)
{
uip_len = 0;
return;
}
uip_stack_set_active (stackno);
/* uip_len is set to the number of data bytes including TCP/UDP/IP header. */
memmove (uip_buf + OPENVPN_TOTAL_LLH_LEN,
uip_buf + BASE_LLH_LEN,
uip_len);
/* Make sure openvpn_process sends the data. */
uip_sappdata = &uip_buf[UIP_LLH_LEN + UIP_IPUDPH_LEN];
uip_slen = uip_len + OPENVPN_HMAC_CRYPT_LEN;
printf ("ready to send %d bytes.\n", uip_slen);
openvpn_encrypt ();
openvpn_hmac_create ();
}
void
router_output(void) {
#ifdef IPCHAIR_HAVE_OUTPUT
ipchair_OUTPUT_chair();
#endif
uint8_t dest = router_find_stack(&BUF->destipaddr);
if (dest == 255)
{
uip_len = 0;
return;
}
router_output_to(dest);
}
void
router_input(uint8_t origin)
{
#ifdef IPCHAIR_HAVE_PREROUTING
ipchair_PREROUTING_chair();
if(!uip_len) return;
#endif
/* uip_len is set to the number of received bytes, including the LLH.
For RFM12, ZBus, etc. it's the full 14-byte Ethernet LLH even also. */
/* Check if packet is addressed to one stack's
configured host address. */
uint8_t dest = router_find_stack(NULL);
if (dest < 255) {
uip_stack_set_active(dest);
#ifdef IPCHAIR_HAVE_INPUT
ipchair_INPUT_chair();
if(!uip_len) return;
#endif
uip_input ();
}
#if UIP_CONF_IPV6 && defined(ENC28J60_SUPPORT)
else if (BUF->destipaddr[0] == HTONS(0xff02))
{
/* Packet is addressed to one of the multicast addresses. */
uip_stack_set_active (STACK_ENC);
uip_input ();
}
#endif /* UIP_CONF_IPV6 */
else
{
#ifdef IP_FORWARDING_SUPPORT
/* Packet not addressed to us, check destination address to where
the packet has to be routed. */
uint8_t dest = router_find_stack(&BUF->destipaddr);
if (dest == 255)
{
uip_len = 0;
return; /* Packet was dropped by the router */
}
if (origin == dest)
goto drop;
if (-- BUF->ttl == 0)
{
/* TODO send ICMP message */
printf ("ttl exceeded, should send ICMP message.\n");
goto drop;
}
#ifdef IPCHAIR_HAVE_FORWARD
ipchair_FORWARD_chair();
if(!uip_len) return;
#endif
#if !UIP_CONF_IPV6
/* For IPv4 we must adjust the chksum */
if(BUF->ipchksum >= HTONS(0xffff - (1 << 8)))
BUF->ipchksum += HTONS(1 << 8) + 1;
else
BUF->ipchksum += HTONS(1 << 8);
#endif
/* For router_output_to uip_len must be set to the number of
bytes to send, excluding the LLH (since it'll generate the needed
one itself). However uip_len is currently set to the number of
received bytes, i.e. including the LLH. */
uip_len -= UIP_LLH_LEN;
/* TODO check MTU and send suitable ICMP message if needed. */
router_output_to (dest);
#endif /* IP_FORWARDING_SUPPORT */
goto drop;
}
return;
drop:
uip_len = 0;
return;
}
