[pptp-server] packet sizes

[robert]

On Monday 07 January 2002 10:03 am, Gustav Jansen wrote:
> Hi!
>
> I've been running pptpd for some time now, and I've suddenly started
> experiencing some weird problems. I get the following message in my kernel
> logs:
>
> Not enough space to encrypt packet: 1404<1404+4!
>
> I'm using PoPToP v1.1.2 and pppd version 2.4.1 on a Linux 2.4.9 box. I've
> set up MPPE 128 and this has been working fine. But now, all of a sudden,
> I can't connect to shares, or connect to the Internet through the
> VPN-link, and these messages are popping up in my logs. Any ideas anyone?

The howto lists this answer:

5.58    Q: I'm getting errors: "Not enough space to encrypt packet: [some 
number]<[somenumber]+4"
        A: You didn't apply the linux-2.4.4-openssl-0.9.6a-mppe.patch.gz 
patch. The problem is that ppp_generic.c assumes that no "compression" method 
will ever cause a frame to grow.  However, MPPE causes every frame to grow by 
four bytes.  This only generates the above error message when you are trying 
to send a frame that is within four bytes of the MTU.

Reducing the MTU will not help because if you reduce the MTU, ppp_generic.c 
will just reduce the size of the buffer that it passes.

Since it was working before, I'm guessing its one of two things: a problem 
with your kernel (did you switch to a new one, did a module get corrupted, 
etc) or you were never actually *USING* the encryption until now.