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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.\" 37.Dd June 7, 2016 38.Dt NG_MPPC 4 39.Os 40.Sh NAME 41.Nm ng_mppc 42.Nd Microsoft MPPC/MPPE compression and encryption netgraph node type 43.Sh SYNOPSIS 44.In sys/types.h 45.In netgraph/ng_mppc.h 46.Sh DESCRIPTION 47The 48.Nm mppc 49node type implements the Microsoft Point-to-Point Compression (MPPC) 50and Microsoft Point-to-Point Encryption (MPPE) sub-protocols of 51the PPP protocol. 52These protocols are often used in conjunction with the Point-to-Point 53Tunneling Protocol (PPTP). 54.Pp 55The node has two hooks, 56.Dv "comp" 57for compression and 58.Dv "decomp" 59for decompression. 60Typically one or both of these hooks would be connected to the 61.Xr ng_ppp 4 62node type hook of the same name. 63Each direction of traffic flow is independent of the other. 64.Sh HOOKS 65This node type supports the following hooks: 66.Bl -tag -width ".Va decomp" 67.It Va comp 68Connection to 69.Xr ng_ppp 4 70.Dv "comp" 71hook. 72Incoming frames are compressed and/or encrypted, and sent 73back out the same hook. 74.It Va decomp 75Connection to 76.Xr ng_ppp 4 77.Dv "decomp" 78hook. 79Incoming frames are decompressed and/or decrypted, and sent 80back out the same hook. 81.El 82.Sh CONTROL MESSAGES 83This node type supports the generic control messages, plus the following: 84.Bl -tag -width foo 85.It Dv NGM_MPPC_CONFIG_COMP 86This command resets and configures the node for a session in the 87outgoing traffic direction (i.e., for compression and/or encryption). 88This command takes a 89.Dv "struct ng_mppc_config" 90as an argument: 91.Bd -literal -offset 0n 92/* Length of MPPE key */ 93#define MPPE_KEY_LEN 16 94 95/* MPPC/MPPE PPP negotiation bits */ 96#define MPPC_BIT 0x00000001 /* mppc compression bits */ 97#define MPPE_40 0x00000020 /* use 40 bit key */ 98#define MPPE_56 0x00000080 /* use 56 bit key */ 99#define MPPE_128 0x00000040 /* use 128 bit key */ 100#define MPPE_BITS 0x000000e0 /* mppe encryption bits */ 101#define MPPE_STATELESS 0x01000000 /* use stateless mode */ 102#define MPPC_VALID_BITS 0x010000e1 /* possibly valid bits */ 103 104/* Configuration for a session */ 105struct ng_mppc_config { 106 u_char enable; /* enable */ 107 uint32_t bits; /* config bits */ 108 u_char startkey[MPPE_KEY_LEN]; /* start key */ 109}; 110 111.Ed 112The 113.Dv enabled 114field enables traffic flow through the node. 115The 116.Dv bits 117field contains the bits as negotiated by the Compression Control Protocol 118(CCP) in PPP. 119The 120.Dv startkey 121is only necessary if MPPE was negotiated, and must be equal to the 122session start key as defined for MPPE. 123This key is based on the MS-CHAP credentials used at link authentication time. 124.It Dv NGM_MPPC_CONFIG_DECOMP 125This command resets and configures the node for a session in the 126incoming traffic direction (i.e., for decompression and/or decryption). 127This command takes a 128.Dv "struct ng_mppc_config" 129as an argument. 130.It Dv NGM_MPPC_RESETREQ 131This message contains no arguments, and is bi-directional. 132If an error is detected during decompression, this message is sent by the 133node to the originator of the 134.Dv NGM_MPPC_CONFIG_DECOMP 135message that initiated the session. 136The receiver should respond by sending a PPP CCP Reset-Request to the peer. 137.Pp 138This message may also be received by this node type when a CCP Reset-Request 139is received by the local PPP entity. 140The node will respond by flushing its outgoing compression and encryption 141state so the remote side can resynchronize. 142.El 143.Sh SHUTDOWN 144This node shuts down upon receipt of a 145.Dv NGM_SHUTDOWN 146control message, or when both hooks have been disconnected. 147.Sh COMPILATION 148The kernel options 149.Dv NETGRAPH_MPPC_COMPRESSION 150and 151.Dv NETGRAPH_MPPC_ENCRYPTION 152are supplied to selectively compile in either or both capabilities. 153At least one of these must be defined, or else this node type is useless. 154.Sh SEE ALSO 155.Xr netgraph 4 , 156.Xr ng_ppp 4 , 157.Xr ngctl 8 158.Rs 159.%A G. Pall 160.%T "Microsoft Point-To-Point Compression (MPPC) Protocol" 161.%O RFC 2118 162.Re 163.Rs 164.%A G. S. Pall 165.%A G. Zorn 166.%T "Microsoft Point-To-Point Encryption (MPPE) Protocol" 167.%O draft-ietf-pppext-mppe-04.txt 168.Re 169.Rs 170.%A K. Hamzeh 171.%A G. Pall 172.%A W. Verthein 173.%A J. Taarud 174.%A W. Little 175.%A G. Zorn 176.%T "Point-to-Point Tunneling Protocol (PPTP)" 177.%O RFC 2637 178.Re 179.Sh AUTHORS 180.An Archie Cobbs Aq Mt archie@FreeBSD.org 181.Sh BUGS 182In PPP, encryption should be handled by the Encryption Control Protocol (ECP) 183rather than CCP. 184However, Microsoft combined both compression and encryption into their 185``compression'' algorithm, which is confusing. 186