This reverts commit 2b9c6812.

Explicitely interpret zero values when parsing boolean options. This
allows to unset boolean parameters such as "verbose" when reloading
the configuration.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

Retrieve the socket address size from the address passed to connect().
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

Use l2tp_tunnel_alloc() cleanup code for handling TID assignment
failure. The previous manual cleanup did not close the triton handler
file descriptor.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

Tunnel establishment may not be immediately followed by the creation of
a new session. In this case there is no message to send to the peer
after receiving an SCCCN; so it won't be acknowledged and the peer will
then have to retransmit it.
This patch makes the tunnel always acknowledge SCCCN by replying with a
ZLB, thus avoiding useless retransmission from the peer.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

Send a ZLB upon reception of a CDN message.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

Update call to l2tp_send_CDN() to avoid using the 0 result code
(reserved by RFC 2661).
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

The sessions timeout timers were registered in the triton context of
their parent tunnel. This patch uses the session's context instead
because the timer's callback function, l2tp_session_timeout(), expects
to be called from a session context.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

When a PPP session terminates on its own (i.e. not on behalf of a L2TP
tunnel/session request), the l2tp_ppp_finished() callback calls the
L2TP session disconnection function without updating the session's
state.
Session disconnection code then works like if the PPP session was still
up: it tries to disconnect the PPP by calling ap_session_terminate().
But since the PPP is already terminated, it returns immediately,
without calling the l2tp_ppp_finished() callback; so session cleanup
won't happen.

This patch updates the session's state upon PPP disconnection, so that
the session disconnection code won't try to disconnect the PPP in
__l2tp_session_free().
The stat_active counter is now updated inside the l2tp_ppp_finished()
callback so that it gets called upon any PPP disconnection.
Sending of the EV_CTRL_FINISHED event has also been moved. It is now
performed in the generic part of __l2tp_session_free() because it has
to be done every time the session really terminates.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

PPP and L2TP session contexts are the same. So since l2tp_ppp_finished()
is called within the PPP context, it doesn't need to switch to the
session context for calling l2tp_ppp_session_disconnect().
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

Freeing a session requires four steps:
  1-The session asynchronously requests its parent tunnel to
    remove the session (the tunnel must start the process).
  2-The parent tunnel removes its reference to this session,
    then makes an asynchronous call to the session cleanup
    function.
  3-The session performs its cleanup, frees its memory and
    asynchronously notifies its parent tunnel.
  4-The parent tunnel decrements its sessions counter (so that
    it knows when it doesn't have any session depending on it).

If two requests, A and B, for removing the same session, arrive
almost simultaneously, then the following scenario may occur:
  1a-The session handles request A and transmits it to its
     parent tunnel.
  2a-The parent tunnel removes its reference to this session
     and requests the session to perform cleanup.
  1b-In the mean time, the session handles request B and
     transmit it to its parent tunnel.
  3a-The session continues to handle request A, cleans up the
     session and frees memory.
  2b-The parent tunnel handles request B: it removes its
     reference to the session and tells it to perform cleanup.
     But the session pointer used has just been freed at step 3a.

This patch modifies step 1, so that the session transmit the
session-id instead of a pointer to the session structure. That
way, the tunnel can check if the session has already been
deleted (or is pending deletion), without having to manipulate a
potentially invalid pointer.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

Use a session counter for each tunnel to avoid freeing a tunnel
while still having sessions depending on it.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>

This reverts commit 3bff891eac97037c633be960b822c688e8629165.

This reverts commit 9f4f36169f03857b6910402028717210270a0339.

* l2tp: Fix allocation checking when adding octets AVP
* cli, tcp: Fix non-NULL terminated string reception
* Fix va_end() missing calls
* chap-secrets: implemented encryption
* auth_pap: make messages like other auth modules
* cli: check xmit_buf is not null at enter to write function
* pppoe: implemented regular expression support
* chap-secrets: implemented encryption
* ippool: fixed initialization order
* optional shaper compiling
* ppp: dns/wins code cleanup

session: don't accept new sessions in shutdown mode