We used to modify in place the packet payload during compression but TCP
stack requires that we don't change the packet payload, therefore we now
copy the whole packet before compression.
Signed-off-by: Sylvain Rochet <gradator@gradator.net>
CCP might negotiate to not compress if peers cannot agree on a
compressor, therefore if the null compressor is chosen we must pass
packets as is instead of dropping them.
Reported-by: Stephan Linz <linz@li-pro.net>
Fixes: 987f6237c4 "PPP, MPPE, drop input/output packets if we couldn't find the chosen decompressor/compressor"
Signed-off-by: Sylvain Rochet <gradator@gradator.net>
The overall lwIP design on data flows (netif,udp,tcp) is to use a user
defined callback to get data from stack and a static function to send
data to stack, which makes perfect sense. The SIO port was an exception,
the PPP stack never really used the SIO port by only using the
sio_send() function (and the ignominious sio_read_abort() function a
while back).
The way the SIO port is currently designed adds a tight coupling between
the lwIP port and the user code if the user need to do specific user
code if the current uart used is the PPPoS uart, which is not nice,
especially because all the lwIP stack is quite clean at this subject.
While we are at stabilizing the PPP API, change this behavior before
it's too late by replacing the static sio_write() calls to a user
defined callback.
The only API difference with and without the PPP_MD5_RANDM support is the
availability of the random_bytes() function. Added a random_bytes()
function on top of magic() when PPP_MD5_RANDM support is not enabled,
thus allowing builds for both cases.
PPP_MD5_RANDM is still enabled by default (it was mandatory) if a protocol
using encryption is enabled, such as CHAP, EAP, or L2TP auth support.
Most of them were wrong actually. We have to use unsigned int because
C90 only allows int types for bitfields, so we are stuck to 32-bit
bitfields in most cases.
We need to do VJ compression before CCP/MPPE compression and VJ
decompression after CCP/MPPE decompression. This leads to a massive
rewrite of how we currently handled VJ only in the PPPoS lower protocol
handler.
Moved VJ structures from pppos to ppp_pcb because we need them back in
PPP core. This is a bit unfortunate because that's not necessary for
PPPoE or PPPoL2TP, but, hey!. Fixed CCP+MPPE+VJ order.
We need to know which methods were chosen when CCP is up, this used to be done
using ccp_test() which we are in the process of removing.
Using non-existing method 0 instead of -1 in CCP for unset method, allowing
type change from s16_t to u8_t for method.
Removed mutiple copies of keys by pre-setting MPPE keys during MSCHAP
negotiation.
Improved MPPE init so we don't need to pass a buffer formatted in a
special way to MPPE, this is necessary for pppd to talk to the kernel,
we don't need that here.
MSCHAP was written the old-way, with all functions declared non static in
header, independent of their local or global scope status. Same for local
constants. Reworked in a more mordern way.
We are going to need ppp_pcb* in MSCHAP and MSCHAPv2 for MPPE for
int mppe_keys_set, u_char mppe_send_key and u_char mppe_recv_key
which are currently global variable which must be moved to ppp_pcb.
