Our PPP stack deals with packet without address and control byte nor 2-byte
protocol field, improved mppe_compress() so we don't have to worry about
them.
mppe_decompress() now takes a pointer to a pbuf pointer and re-use the
passed buffer for MPPE "decompression". Removed sub protocol handling
which can be shared among all decompressors in ppp.c
Replaced ip4_addr_t to ip_addr_t in pppapi_pppol2tp_create() prototype,
now binding to UDPv6 or UDPv4 depending on the passed ip_addr_t type.
Removed pppol2tp_create_ip6() and pppapi_pppol2tp_create_ip6().
ip_addr_t is used for all generic IP addresses for the API, ip(4/6)_addr_t are only used internally or when initializing netifs or when calling version-related functions
Follow-up of the #44565 bug fix, renamed the misnamed
PPP_INPROC_MULTITHREADED to PPP_INPROC_IRQ_SAFE because it is
IRQ safe but not thread safe.
Updated PPP documentation which now clearly state when and how
this feature can be used.
If PPP_INPROC_MULTITHREADED is true, then user does not what to use
the TCPIP API. Disabling the TCPIP API helps the user to understand
that PPP_INPROC_MULTITHREADED must not be used if he wish to use
the TCPIP API.
Don't process input data if PPPoS is closed, it helps using
pppos_input() from a different context to prevent pppos_input() to
modify PPPoS RX machine state on a closed PPPoS session. It also
prevents allocating pbuf (which are going to be tossed out by PPP core)
and parsing serial input on a closed session.
It only mitigates the fact that this function is actually NOT thread
safe in absolutely all cases, it does not fix it but it helps for a low
cost.
For example user application should never call pppos_input() while
pppos_connect() or pppos_listen() is currently running because both of
them are freeing any input pbuf left over from the last session before
resetting the PPPoS state, they really have to to prevent pbuf leaks.
We cannot fix that easily because we don't have spinlock with an
irqsave/irqrestore helper for IRQ contexts. Mutex cannot be used in
interrupt contexts (or again, with an IRQ mutex helper).
We are going to improve the documentation on this point.
PPPoS was actually not thread safe, pppos_input() can be called from
lwIP user port at any time, whatever the PPP state is. It might even be
called during pppos_connect() and pppos_listen(), this is quite unlikely
the port do that but nothing prevent the user to since we document
pppos_input() as being thread safe.
Added a mutex if PPP_INPROC_MULTITHREADED is set and ensure pppos_input()
is safe in regard to other pppos_* functions.
Makes it clear we are initiating the PPP session with ppp_connect
(i.e. acting as a PPP client) so there is no confusion possible
between ppp_connect and ppp_listen.
Prepare for PPP_SERVER support, we need to move auth configuration before
lcp_allowoptions is copied into lcp_gotoptions. Restore unused
auth_reset() function using pppd original source code.
