[PPP]: add PPP MPPE encryption module
From: Matt Domsch <Matt_Domsch@dell.com>
The patch below implements the Microsoft Point-to-Point Encryption method
as a PPP compressor/decompressor. This is necessary for Linux clients and
servers to interoperate with Microsoft Point-to-Point Tunneling Protocol
(PPTP) servers (either Microsoft PPTP servers or the poptop project) which
use MPPE to encrypt data when creating a VPN.
This patch differs from the kernel_ppp_mppe DKMS pacakge at
pptpclient.sourceforge.net by utilizing the kernel crypto routines rather
than providing its own SHA1 and arcfour implementations.
Minor changes to ppp_generic.c try to prevent a link from disabling
compression (in our case, the encryption) after it has started using
compression (encryption).
Feedback to <pptpclient-devel@lists.sourceforge.net> please.
Signed-off-by: Matt Domsch <Matt_Domsch@dell.com>
Cc: James Cameron <james.cameron@hp.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Brice Goglin <Brice.Goglin@ens-lyon.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 1958d9e..24f1691 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2523,6 +2523,19 @@
module; it is called bsd_comp and will show up in the directory
modules once you have said "make modules". If unsure, say N.
+config PPP_MPPE
+ tristate "PPP MPPE compression (encryption) (EXPERIMENTAL)"
+ depends on PPP && EXPERIMENTAL
+ select CRYPTO
+ select CRYPTO_SHA1
+ select CRYPTO_ARC4
+ ---help---
+ Support for the MPPE Encryption protocol, as employed by the
+ Microsoft Point-to-Point Tunneling Protocol.
+
+ See http://pptpclient.sourceforge.net/ for information on
+ configuring PPTP clients and servers to utilize this method.
+
config PPPOE
tristate "PPP over Ethernet (EXPERIMENTAL)"
depends on EXPERIMENTAL && PPP