Re: MPPE in kernel?

[Paul Mackerras]

Frank Cusack writes:

> When (if) CCP goes down, pppd shuts down LCP if MPPE was running.

Not good enough - you have a window when the kernel will be
transmitting unencrypted datagrams while pppd responds.

Look at the places in ppp_generic.c where the driver clears
SC_COMP_RUN or SC_DECOMP_RUN - for example when it receives a CCP
terminate-request or configure-request.  You need to do something to
make sure that the kernel never transmits data packets when
SC_COMP_RUN is clear if you are doing MPPE.  Similarly, if you are
doing MPPE you probably need to discard received unencrypted data
packets.

Paul.