void
process_incoming_tun (struct context *c)
{
struct gc_arena gc = gc_new ();
perf_push (PERF_PROC_IN_TUN);
if (c->c2.buf.len > 0)
c->c2.tun_read_bytes += c->c2.buf.len;
#ifdef LOG_RW
if (c->c2.log_rw && c->c2.buf.len > 0)
fprintf (stderr, "r");
#endif
/* Show packet content */
dmsg (D_TUN_RW, "TUN READ [%d]", BLEN (&c->c2.buf));
if (c->c2.buf.len > 0)
{
if ((c->options.mode == MODE_POINT_TO_POINT) && (!c->options.allow_recursive_routing))
drop_if_recursive_routing (c, &c->c2.buf);
/*
* The --passtos and --mssfix options require
* us to examine the IP header (IPv4 or IPv6).
*/
process_ip_header (c, PIPV4_PASSTOS|PIP_MSSFIX|PIPV4_CLIENT_NAT, &c->c2.buf);
#ifdef PACKET_TRUNCATION_CHECK
/* if (c->c2.buf.len > 1) --c->c2.buf.len; */
ipv4_packet_size_verify (BPTR (&c->c2.buf),
BLEN (&c->c2.buf),
TUNNEL_TYPE (c->c1.tuntap),
"PRE_ENCRYPT",
&c->c2.n_trunc_pre_encrypt);
#endif
encrypt_sign (c, true);
}
else
{
buf_reset (&c->c2.to_link);
}
perf_pop ();
gc_free (&gc);
}
void
process_outgoing_tun (struct context *c)
{
struct gc_arena gc = gc_new ();
/*
* Set up for write() call to TUN/TAP
* device.
*/
if (c->c2.to_tun.len <= 0)
return;
perf_push (PERF_PROC_OUT_TUN);
/*
* The --mssfix option requires
* us to examine the IP header (IPv4 or IPv6).
*/
process_ip_header (c, PIP_MSSFIX|PIPV4_EXTRACT_DHCP_ROUTER|PIPV4_CLIENT_NAT|PIPV4_OUTGOING, &c->c2.to_tun);
if (c->c2.to_tun.len <= MAX_RW_SIZE_TUN (&c->c2.frame))
{
/*
* Write to TUN/TAP device.
*/
int size;
#ifdef LOG_RW
if (c->c2.log_rw)
fprintf (stderr, "w");
#endif
dmsg (D_TUN_RW, "TUN WRITE [%d]", BLEN (&c->c2.to_tun));
#ifdef PACKET_TRUNCATION_CHECK
ipv4_packet_size_verify (BPTR (&c->c2.to_tun),
BLEN (&c->c2.to_tun),
TUNNEL_TYPE (c->c1.tuntap),
"WRITE_TUN",
&c->c2.n_trunc_tun_write);
#endif
#ifdef TUN_PASS_BUFFER
size = write_tun_buffered (c->c1.tuntap, &c->c2.to_tun);
#else
size = write_tun (c->c1.tuntap, BPTR (&c->c2.to_tun), BLEN (&c->c2.to_tun));
#endif
if (size > 0)
c->c2.tun_write_bytes += size;
check_status (size, "write to TUN/TAP", NULL, c->c1.tuntap);
/* check written packet size */
if (size > 0)
{
/* Did we write a different size packet than we intended? */
if (size != BLEN (&c->c2.to_tun))
msg (D_LINK_ERRORS,
"TUN/TAP packet was destructively fragmented on write to %s (tried=%d,actual=%d)",
c->c1.tuntap->actual_name,
BLEN (&c->c2.to_tun),
size);
/* indicate activity regarding --inactive parameter */
register_activity (c, size);
}
}
else
{
/*
* This should never happen, probably indicates some kind
* of MTU mismatch.
*/
msg (D_LINK_ERRORS, "tun packet too large on write (tried=%d,max=%d)",
c->c2.to_tun.len,
MAX_RW_SIZE_TUN (&c->c2.frame));
}
buf_reset (&c->c2.to_tun);
perf_pop ();
gc_free (&gc);
}