1.\" Copyright (c) 1996-2000 Whistle Communications, Inc. 2.\" All rights reserved. 3.\" 4.\" Subject to the following obligations and disclaimer of warranty, use and 5.\" redistribution of this software, in source or object code forms, with or 6.\" without modifications are expressly permitted by Whistle Communications; 7.\" provided, however, that: 8.\" 1. Any and all reproductions of the source or object code must include the 9.\" copyright notice above and the following disclaimer of warranties; and 10.\" 2. No rights are granted, in any manner or form, to use Whistle 11.\" Communications, Inc. trademarks, including the mark "WHISTLE 12.\" COMMUNICATIONS" on advertising, endorsements, or otherwise except as 13.\" such appears in the above copyright notice or in the software. 14.\" 15.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 16.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 17.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 18.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 19.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 20.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 21.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 22.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 23.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 24.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 25.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 26.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 27.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 28.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 31.\" OF SUCH DAMAGE. 32.\" 33.\" Author: Archie Cobbs <archie@FreeBSD.org> 34.\" 35.\" $Whistle: ng_mppc.8,v 1.1 1999/12/08 20:20:39 archie Exp $ 36.\" $FreeBSD$ 37.\" 38.Dd December 8, 1999 39.Dt NG_MPPC 4 40.Os 41.Sh NAME 42.Nm ng_mppc 43.Nd Microsoft MPPC/MPPE compression and encryption netgraph node type 44.Sh SYNOPSIS 45.In sys/types.h 46.In netgraph/ng_mppc.h 47.Sh DESCRIPTION 48The 49.Nm mppc 50node type implements the Microsoft Point-to-Point Compression (MPPC) 51and Microsoft Point-to-Point Encryption (MPPE) sub-protocols of 52the PPP protocol. 53These protocols are often used in conjunction with the Point-to-Point 54Tunneling Protocol (PPTP). 55.Pp 56The node has two hooks, 57.Dv "comp" 58for compression and 59.Dv "decomp" 60for decompression. 61Typically one or both of these hooks would be connected to the 62.Xr ng_ppp 4 63node type hook of the same name. 64Each direction of traffic flow is independent of the other. 65.Sh HOOKS 66This node type supports the following hooks: 67.Bl -tag -width ".Va decomp" 68.It Va comp 69Connection to 70.Xr ng_ppp 4 71.Dv "comp" 72hook. 73Incoming frames are compressed and/or encrypted, and sent 74back out the same hook. 75.It Va decomp 76Connection to 77.Xr ng_ppp 4 78.Dv "decomp" 79hook. 80Incoming frames are decompressed and/or decrypted, and sent 81back out the same hook. 82.El 83.Sh CONTROL MESSAGES 84This node type supports the generic control messages, plus the following: 85.Bl -tag -width foo 86.It Dv NGM_MPPC_CONFIG_COMP 87This command resets and configures the node for a session in the 88outgoing traffic direction (i.e., for compression and/or encryption). 89This command takes a 90.Dv "struct ng_mppc_config" 91as an argument: 92.Bd -literal -offset 0n 93/* Length of MPPE key */ 94#define MPPE_KEY_LEN 16 95 96/* MPPC/MPPE PPP negotiation bits */ 97#define MPPC_BIT 0x00000001 /* mppc compression bits */ 98#define MPPE_40 0x00000020 /* use 40 bit key */ 99#define MPPE_56 0x00000080 /* use 56 bit key */ 100#define MPPE_128 0x00000040 /* use 128 bit key */ 101#define MPPE_BITS 0x000000e0 /* mppe encryption bits */ 102#define MPPE_STATELESS 0x01000000 /* use stateless mode */ 103#define MPPC_VALID_BITS 0x010000e1 /* possibly valid bits */ 104 105/* Configuration for a session */ 106struct ng_mppc_config { 107 u_char enable; /* enable */ 108 uint32_t bits; /* config bits */ 109 u_char startkey[MPPE_KEY_LEN]; /* start key */ 110}; 111 112.Ed 113The 114.Dv enabled 115field enables traffic flow through the node. 116The 117.Dv bits 118field contains the bits as negotiated by the Compression Control Protocol 119(CCP) in PPP. 120The 121.Dv startkey 122is only necessary if MPPE was negotiated, and must be equal to the 123session start key as defined for MPPE. 124This key is based on the MS-CHAP credentials used at link authentication time. 125.It Dv NGM_MPPC_CONFIG_DECOMP 126This command resets and configures the node for a session in the 127incoming traffic direction (i.e., for decompression and/or decryption). 128This command takes a 129.Dv "struct ng_mppc_config" 130as an argument. 131.It Dv NGM_MPPC_RESETREQ 132This message contains no arguments, and is bi-directional. 133If an error is detected during decompression, this message is sent by the 134node to the originator of the 135.Dv NGM_MPPC_CONFIG_DECOMP 136message that initiated the session. 137The receiver should respond by sending a PPP CCP Reset-Request to the peer. 138.Pp 139This message may also be received by this node type when a CCP Reset-Request 140is received by the local PPP entity. 141The node will respond by flushing its outgoing compression and encryption 142state so the remote side can resynchronize. 143.El 144.Sh SHUTDOWN 145This node shuts down upon receipt of a 146.Dv NGM_SHUTDOWN 147control message, or when both hooks have been disconnected. 148.Sh COMPILATION 149The kernel options 150.Dv NETGRAPH_MPPC_COMPRESSION 151and 152.Dv NETGRAPH_MPPC_ENCRYPTION 153are supplied to selectively compile in either or both capabilities. 154At least one of these must be defined, or else this node type is useless. 155.Pp 156The MPPC protocol requires proprietary compression code available 157from Hi/Fn (formerly STAC). 158These files must be obtained elsewhere and added to the kernel 159sources before this node type will compile with the 160.Dv NETGRAPH_MPPC_COMPRESSION 161option. 162.Sh SEE ALSO 163.Xr netgraph 4 , 164.Xr ng_ppp 4 , 165.Xr ngctl 8 166.Rs 167.%A G. Pall 168.%T "Microsoft Point-To-Point Compression (MPPC) Protocol" 169.%O RFC 2118 170.Re 171.Rs 172.%A G. S. Pall 173.%A G. Zorn 174.%T "Microsoft Point-To-Point Encryption (MPPE) Protocol" 175.%O draft-ietf-pppext-mppe-04.txt 176.Re 177.Rs 178.%A K. Hamzeh 179.%A G. Pall 180.%A W. Verthein 181.%A J. Taarud 182.%A W. Little 183.%A G. Zorn 184.%T "Point-to-Point Tunneling Protocol (PPTP)" 185.%O RFC 2637 186.Re 187.Sh AUTHORS 188.An Archie Cobbs Aq archie@FreeBSD.org 189.Sh BUGS 190In PPP, encryption should be handled by the Encryption Control Protocol (ECP) 191rather than CCP. 192However, Microsoft combined both compression and encryption into their 193``compression'' algorithm, which is confusing. 194