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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: src/share/man/man4/ng_mppc.4,v 1.11.2.3 2002/03/20 18:16:36 archie Exp $ 37.\" $DragonFly: src/share/man/man4/ng_mppc.4,v 1.4 2006/05/26 19:39:39 swildner Exp $ 38.\" 39.Dd December 8, 1999 40.Dt NG_MPPC 4 41.Os 42.Sh NAME 43.Nm ng_mppc 44.Nd Microsoft MPPC/MPPE compression and encryption netgraph node type 45.Sh SYNOPSIS 46.In netgraph/mppc/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.Pp 68.Bl -tag -compact -width vjc_vjuncomp 69.It Dv comp 70Connection to 71.Xr ng_ppp 4 72.Dv "comp" 73hook. 74Incoming frames are compressed and/or encrypted, and sent 75back out the same hook. 76.It Dv decomp 77Connection to 78.Xr ng_ppp 4 79.Dv "decomp" 80hook. 81Incoming frames are decompressed and/or decrypted, and sent 82back out the same hook. 83.El 84.Sh CONTROL MESSAGES 85This node type supports the generic control messages, plus the following: 86.Bl -tag -width foo 87.It Dv NGM_MPPC_CONFIG_COMP 88This command resets and configures the node for a session in the 89outgoing traffic direction (i.e., for compression and/or encryption). 90This command takes a 91.Dv "struct ng_mppc_config" 92as an argument: 93.Bd -literal -offset 0n 94/* Length of MPPE key */ 95#define MPPE_KEY_LEN 16 96 97/* MPPC/MPPE PPP negotiation bits */ 98#define MPPC_BIT 0x00000001 /* mppc compression bits */ 99#define MPPE_40 0x00000020 /* use 40 bit key */ 100#define MPPE_56 0x00000080 /* use 56 bit key */ 101#define MPPE_128 0x00000040 /* use 128 bit key */ 102#define MPPE_BITS 0x000000e0 /* mppe encryption bits */ 103#define MPPE_STATELESS 0x01000000 /* use stateless mode */ 104#define MPPC_VALID_BITS 0x010000e1 /* possibly valid bits */ 105 106/* Configuration for a session */ 107struct ng_mppc_config { 108 u_char enable; /* enable */ 109 u_int32_t bits; /* config bits */ 110 u_char startkey[MPPE_KEY_LEN]; /* start key */ 111}; 112 113.Ed 114The 115.Dv enabled 116field enables traffic flow through the node. 117The 118.Dv bits 119field contains the bits as negotiated by the Compression Control Protocol 120(CCP) in PPP. 121The 122.Dv startkey 123is only necessary if MPPE was negotiated, and must be equal to the 124session start key as defined for MPPE. 125This key is based on the MS-CHAP credentials used at link authentication time. 126.It Dv NGM_MPPC_CONFIG_DECOMP 127This command resets and configures the node for a session in the 128incoming traffic direction (i.e., for decompression and/or decryption). 129This command takes a 130.Dv "struct ng_mppc_config" 131as an argument. 132.It Dv NGM_MPPC_RESETREQ 133This message contains no arguments, and is bi-directional. 134If an error is detected during decompression, this message is sent by the 135node to the originator of the 136.Dv NGM_MPPC_CONFIG_DECOMP 137message that initiated the session. 138The receiver should respond by sending a PPP CCP Reset-Request to the peer. 139.Pp 140This message may also be received by this node type when a CCP Reset-Request 141is received by the local PPP entity. 142The node will respond by flushing its outgoing compression and encryption 143state so the remote side can resynchronize. 144.El 145.Sh SHUTDOWN 146This node shuts down upon receipt of a 147.Dv NGM_SHUTDOWN 148control message, or when both hooks have been disconnected. 149.Sh COMPILATION 150The kernel options 151.Dv NETGRAPH_MPPC_COMPRESSION 152and 153.Dv NETGRAPH_MPPC_ENCRYPTION 154are supplied to selectively compile in either or both capabilities. 155At least one of these must be defined, or else this node type is useless. 156.Pp 157The MPPC protocol requires proprietary compression code available 158from Hi/Fn (formerly STAC). 159These files must be obtained elsewhere and added to the kernel 160sources before this node type will compile with the 161.Dv NETGRAPH_MPPC_COMPRESSION 162option. 163.Sh SEE ALSO 164.Xr netgraph 4 , 165.Xr ng_ppp 4 , 166.Xr ngctl 8 167.Rs 168.%A G. Pall 169.%T "Microsoft Point-To-Point Compression (MPPC) Protocol" 170.%O RFC 2118 171.Re 172.Rs 173.%A G. S. Pall 174.%A G. Zorn 175.%T "Microsoft Point-To-Point Encryption (MPPE) Protocol" 176.%O draft-ietf-pppext-mppe-04.txt 177.Re 178.Rs 179.%A K. Hamzeh 180.%A G. Pall 181.%A W. Verthein 182.%A J. Taarud 183.%A W. Little 184.%A G. Zorn 185.%T "Point-to-Point Tunneling Protocol (PPTP)" 186.%O RFC 2637 187.Re 188.Sh AUTHORS 189.An Archie Cobbs Aq archie@FreeBSD.org 190.Sh BUGS 191In PPP, encryption should be handled by the Encryption Control Protocol (ECP) 192rather than CCP. 193However, Microsoft combined both compression and encryption into their 194``compression'' algorithm, which is confusing. 195