void
read_incoming_tun (struct context *c)
{
/*
* Setup for read() call on TUN/TAP device.
*/
/*ASSERT (!c->c2.to_link.len);*/
perf_push (PERF_READ_IN_TUN);
c->c2.buf = c->c2.buffers->read_tun_buf;
#ifdef TUN_PASS_BUFFER
read_tun_buffered (c->c1.tuntap, &c->c2.buf, MAX_RW_SIZE_TUN (&c->c2.frame));
#else
ASSERT (buf_init (&c->c2.buf, FRAME_HEADROOM (&c->c2.frame)));
ASSERT (buf_safe (&c->c2.buf, MAX_RW_SIZE_TUN (&c->c2.frame)));
c->c2.buf.len = read_tun (c->c1.tuntap, BPTR (&c->c2.buf), MAX_RW_SIZE_TUN (&c->c2.frame));
#endif
#ifdef PACKET_TRUNCATION_CHECK
ipv4_packet_size_verify (BPTR (&c->c2.buf),
BLEN (&c->c2.buf),
TUNNEL_TYPE (c->c1.tuntap),
"READ_TUN",
&c->c2.n_trunc_tun_read);
#endif
/* Was TUN/TAP interface stopped? */
if (tuntap_stop (c->c2.buf.len))
{
register_signal (c, SIGTERM, "tun-stop");
msg (M_INFO, "TUN/TAP interface has been stopped, exiting");
perf_pop ();
return;
}
/* Was TUN/TAP I/O operation aborted? */
if (tuntap_abort(c->c2.buf.len))
{
register_signal(c, SIGHUP, "tun-abort");
c->persist.restart_sleep_seconds = 10;
msg(M_INFO, "TUN/TAP I/O operation aborted, restarting");
perf_pop();
return;
}
/* Check the status return from read() */
check_status (c->c2.buf.len, "read from TUN/TAP", NULL, c->c1.tuntap);
perf_pop ();
}
/* allocate a buffer for socket or tun layer */
void
alloc_buf_sock_tun (struct buffer *buf,
const struct frame *frame,
const bool tuntap_buffer,
const unsigned int align_mask)
{
/* allocate buffer for overlapped I/O */
*buf = alloc_buf (BUF_SIZE (frame));
ASSERT (buf_init (buf, FRAME_HEADROOM_ADJ (frame, align_mask)));
buf->len = tuntap_buffer ? MAX_RW_SIZE_TUN (frame) : MAX_RW_SIZE_LINK (frame);
ASSERT (buf_safe (buf, 0));
}
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 IPv4 header.
*/
process_ipv4_header (c, PIPV4_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);
}
void
check_send_occ_msg_dowork (struct context *c)
{
bool doit = false;
c->c2.buf = c->c2.buffers->aux_buf;
ASSERT (buf_init (&c->c2.buf, FRAME_HEADROOM (&c->c2.frame)));
ASSERT (buf_safe (&c->c2.buf, MAX_RW_SIZE_TUN (&c->c2.frame)));
ASSERT (buf_write (&c->c2.buf, occ_magic, OCC_STRING_SIZE));
switch (c->c2.occ_op)
{
case OCC_REQUEST:
if (!buf_write_u8 (&c->c2.buf, OCC_REQUEST))
break;
dmsg (D_PACKET_CONTENT, "SENT OCC_REQUEST");
doit = true;
break;
case OCC_REPLY:
if (!c->c2.options_string_local)
break;
if (!buf_write_u8 (&c->c2.buf, OCC_REPLY))
break;
if (!buf_write (&c->c2.buf, c->c2.options_string_local,
strlen (c->c2.options_string_local) + 1))
break;
dmsg (D_PACKET_CONTENT, "SENT OCC_REPLY");
doit = true;
break;
case OCC_MTU_REQUEST:
if (!buf_write_u8 (&c->c2.buf, OCC_MTU_REQUEST))
break;
dmsg (D_PACKET_CONTENT, "SENT OCC_MTU_REQUEST");
doit = true;
break;
case OCC_MTU_REPLY:
if (!buf_write_u8 (&c->c2.buf, OCC_MTU_REPLY))
break;
if (!buf_write_u16 (&c->c2.buf, c->c2.max_recv_size_local))
break;
if (!buf_write_u16 (&c->c2.buf, c->c2.max_send_size_local))
break;
dmsg (D_PACKET_CONTENT, "SENT OCC_MTU_REPLY");
doit = true;
break;
case OCC_MTU_LOAD_REQUEST:
if (!buf_write_u8 (&c->c2.buf, OCC_MTU_LOAD_REQUEST))
break;
if (!buf_write_u16 (&c->c2.buf, c->c2.occ_mtu_load_size))
break;
dmsg (D_PACKET_CONTENT, "SENT OCC_MTU_LOAD_REQUEST");
doit = true;
break;
case OCC_MTU_LOAD:
{
int need_to_add;
if (!buf_write_u8 (&c->c2.buf, OCC_MTU_LOAD))
break;
need_to_add = min_int (c->c2.occ_mtu_load_size, EXPANDED_SIZE (&c->c2.frame))
- OCC_STRING_SIZE
- sizeof (uint8_t)
- EXTRA_FRAME (&c->c2.frame);
while (need_to_add > 0)
{
/*
* Fill the load test packet with pseudo-random bytes.
*/
if (!buf_write_u8 (&c->c2.buf, get_random () & 0xFF))
break;
--need_to_add;
}
dmsg (D_PACKET_CONTENT, "SENT OCC_MTU_LOAD min_int(%d-%d-%d-%d,%d) size=%d",
c->c2.occ_mtu_load_size,
OCC_STRING_SIZE,
(int) sizeof (uint8_t),
EXTRA_FRAME (&c->c2.frame),
MAX_RW_SIZE_TUN (&c->c2.frame),
BLEN (&c->c2.buf));
doit = true;
}
break;
case OCC_EXIT:
if (!buf_write_u8 (&c->c2.buf, OCC_EXIT))
break;
dmsg (D_PACKET_CONTENT, "SENT OCC_EXIT");
doit = true;
break;
}
if (doit)
{
/*
* We will treat the packet like any other outgoing packet,
* compress, encrypt, sign, etc.
*/
encrypt_sign (c, true);
}
c->c2.occ_op = -1;
}
/*
* Should we ping the remote?
*/
void
check_ping_send_dowork (struct context *c)
{
c->c2.buf = c->c2.buffers->aux_buf;
ASSERT (buf_init (&c->c2.buf, FRAME_HEADROOM (&c->c2.frame)));
ASSERT (buf_safe (&c->c2.buf, MAX_RW_SIZE_TUN (&c->c2.frame)));
ASSERT (buf_write (&c->c2.buf, ping_string, sizeof (ping_string)));
/*
* We will treat the ping like any other outgoing packet,
* encrypt, sign, etc.
*/
encrypt_sign (c, true);
dmsg (D_PING, "SENT PING");
}