Home | History | Annotate | Download | only in src
      1 /*-
      2  * Copyright (c) 1996 - 2001 Brian Somers <brian (at) Awfulhak.org>
      3  *          based on work by Toshiharu OHNO <tony-o (at) iij.ad.jp>
      4  *                           Internet Initiative Japan, Inc (IIJ)
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     26  * SUCH DAMAGE.
     27  *
     28  * $FreeBSD: src/usr.sbin/ppp/vjcomp.c,v 1.40.26.1 2010/12/21 17:10:29 kensmith Exp $
     29  */
     30 
     31 #include <sys/param.h>
     32 #include <netinet/in.h>
     33 #include <netinet/in_systm.h>
     34 #include <netinet/ip.h>
     35 #include <sys/socket.h>
     36 #include <sys/un.h>
     37 
     38 #include <stdio.h>
     39 #include <string.h>		/* strlen/memcpy */
     40 #include <termios.h>
     41 
     42 #include "layer.h"
     43 #include "mbuf.h"
     44 #include "log.h"
     45 #include "timer.h"
     46 #include "fsm.h"
     47 #include "proto.h"
     48 #include "slcompress.h"
     49 #include "lqr.h"
     50 #include "hdlc.h"
     51 #include "defs.h"
     52 #include "iplist.h"
     53 #include "throughput.h"
     54 #include "ncpaddr.h"
     55 #include "ipcp.h"
     56 #include "lcp.h"
     57 #include "ccp.h"
     58 #include "link.h"
     59 #include "filter.h"
     60 #include "descriptor.h"
     61 #include "mp.h"
     62 #ifndef NORADIUS
     63 #include "radius.h"
     64 #endif
     65 #include "ipv6cp.h"
     66 #include "ncp.h"
     67 #include "bundle.h"
     68 #include "vjcomp.h"
     69 
     70 #define MAX_VJHEADER 16		/* Maximum size of compressed header */
     71 
     72 static struct mbuf *
     73 vj_LayerPush(struct bundle *bundle, struct link *l __unused, struct mbuf *bp,
     74 	     int pri __unused, u_short *proto)
     75 {
     76   int type;
     77   struct ip *pip;
     78   u_short cproto = bundle->ncp.ipcp.peer_compproto >> 16;
     79 
     80   bp = m_pullup(bp);
     81   pip = (struct ip *)MBUF_CTOP(bp);
     82   if (*proto == PROTO_IP && pip->ip_p == IPPROTO_TCP &&
     83       cproto == PROTO_VJCOMP) {
     84     type = sl_compress_tcp(bp, pip, &bundle->ncp.ipcp.vj.cslc,
     85                            &bundle->ncp.ipcp.vj.slstat,
     86                            bundle->ncp.ipcp.peer_compproto & 0xff);
     87     log_Printf(LogDEBUG, "vj_LayerWrite: type = %x\n", type);
     88     switch (type) {
     89     case TYPE_IP:
     90       break;
     91 
     92     case TYPE_UNCOMPRESSED_TCP:
     93       *proto = PROTO_VJUNCOMP;
     94       log_Printf(LogDEBUG, "vj_LayerPush: PROTO_IP -> PROTO_VJUNCOMP\n");
     95       m_settype(bp, MB_VJOUT);
     96       break;
     97 
     98     case TYPE_COMPRESSED_TCP:
     99       *proto = PROTO_VJCOMP;
    100       log_Printf(LogDEBUG, "vj_LayerPush: PROTO_IP -> PROTO_VJUNCOMP\n");
    101       m_settype(bp, MB_VJOUT);
    102       break;
    103 
    104     default:
    105       log_Printf(LogERROR, "vj_LayerPush: Unknown frame type %x\n", type);
    106       m_freem(bp);
    107       return NULL;
    108     }
    109   }
    110 
    111   return bp;
    112 }
    113 
    114 static struct mbuf *
    115 VjUncompressTcp(struct ipcp *ipcp, struct mbuf *bp, u_char type)
    116 {
    117   u_char *bufp;
    118   int len, olen, rlen;
    119   u_char work[MAX_HDR + MAX_VJHEADER];	/* enough to hold TCP/IP header */
    120 
    121   bp = m_pullup(bp);
    122   olen = len = m_length(bp);
    123   if (type == TYPE_UNCOMPRESSED_TCP) {
    124     /*
    125      * Uncompressed packet does NOT change its size, so that we can use mbuf
    126      * space for uncompression job.
    127      */
    128     bufp = MBUF_CTOP(bp);
    129     len = sl_uncompress_tcp(&bufp, len, type, &ipcp->vj.cslc, &ipcp->vj.slstat,
    130                             (ipcp->my_compproto >> 8) & 255);
    131     if (len <= 0) {
    132       m_freem(bp);
    133       bp = NULL;
    134     } else
    135       m_settype(bp, MB_VJIN);
    136     return bp;
    137   }
    138 
    139   /*
    140    * Handle compressed packet. 1) Read upto MAX_VJHEADER bytes into work
    141    * space. 2) Try to uncompress it. 3) Compute amount of necessary space. 4)
    142    * Copy unread data info there.
    143    */
    144   if (len > MAX_VJHEADER)
    145     len = MAX_VJHEADER;
    146   rlen = len;
    147   bufp = work + MAX_HDR;
    148   bp = mbuf_Read(bp, bufp, rlen);
    149   len = sl_uncompress_tcp(&bufp, olen, type, &ipcp->vj.cslc, &ipcp->vj.slstat,
    150                           (ipcp->my_compproto >> 8) & 255);
    151   if (len <= 0) {
    152     m_freem(bp);
    153     return NULL;
    154   }
    155   len -= olen;
    156   len += rlen;
    157 
    158   bp = m_prepend(bp, bufp, len, 0);
    159   m_settype(bp, MB_VJIN);
    160 
    161   return bp;
    162 }
    163 
    164 static struct mbuf *
    165 vj_LayerPull(struct bundle *bundle, struct link *l __unused, struct mbuf *bp,
    166              u_short *proto)
    167 {
    168   u_char type;
    169 
    170   switch (*proto) {
    171   case PROTO_VJCOMP:
    172     type = TYPE_COMPRESSED_TCP;
    173     log_Printf(LogDEBUG, "vj_LayerPull: PROTO_VJCOMP -> PROTO_IP\n");
    174     break;
    175   case PROTO_VJUNCOMP:
    176     type = TYPE_UNCOMPRESSED_TCP;
    177     log_Printf(LogDEBUG, "vj_LayerPull: PROTO_VJUNCOMP -> PROTO_IP\n");
    178     break;
    179   default:
    180     return bp;
    181   }
    182 
    183   *proto = PROTO_IP;
    184   return VjUncompressTcp(&bundle->ncp.ipcp, bp, type);
    185 }
    186 
    187 const char *
    188 vj2asc(u_int32_t val)
    189 {
    190   static char asc[50];		/* The return value is used immediately */
    191 
    192   if (val)
    193     snprintf(asc, sizeof asc, "%d VJ slots with%s slot compression",
    194             (int)((val>>8)&15)+1, val & 1 ?  "" : "out");
    195   else
    196     strcpy(asc, "VJ disabled");
    197   return asc;
    198 }
    199 
    200 struct layer vjlayer = { LAYER_VJ, "vj", vj_LayerPush, vj_LayerPull };
    201