usr.sbin/ppp/vjcomp.c

   1 /*-
   2  * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
   3  *          based on work by Toshiharu OHNO <tony-o@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 1.35.2.2 2002/09/01 02:12:32 brian Exp $
  29  * $DragonFly: src/usr.sbin/ppp/vjcomp.c,v 1.2 2003/06/17 04:30:01 dillon Exp $
  30  */
  31
  32 #include <sys/param.h>
  33 #include <netinet/in.h>
  34 #include <netinet/in_systm.h>
  35 #include <netinet/ip.h>
  36 #include <sys/socket.h>
  37 #include <sys/un.h>
  38
  39 #include <stdio.h>
  40 #include <string.h>             /* strlen/memcpy */
  41 #include <termios.h>
  42
  43 #include "layer.h"
  44 #include "mbuf.h"
  45 #include "log.h"
  46 #include "timer.h"
  47 #include "fsm.h"
  48 #include "proto.h"
  49 #include "slcompress.h"
  50 #include "lqr.h"
  51 #include "hdlc.h"
  52 #include "defs.h"
  53 #include "iplist.h"
  54 #include "throughput.h"
  55 #include "ncpaddr.h"
  56 #include "ipcp.h"
  57 #include "lcp.h"
  58 #include "ccp.h"
  59 #include "link.h"
  60 #include "filter.h"
  61 #include "descriptor.h"
  62 #include "mp.h"
  63 #ifndef NORADIUS
  64 #include "radius.h"
  65 #endif
  66 #include "ipv6cp.h"
  67 #include "ncp.h"
  68 #include "bundle.h"
  69 #include "vjcomp.h"
  70
  71 #define MAX_VJHEADER 16         /* Maximum size of compressed header */
  72
  73 static struct mbuf *
  74 vj_LayerPush(struct bundle *bundle, struct link *l __unused, struct mbuf *bp, int pri __unused,
  75              u_short *proto)
  76 {
  77   int type;
  78   struct ip *pip;
  79   u_short cproto = bundle->ncp.ipcp.peer_compproto >> 16;
  80
  81   bp = m_pullup(bp);
  82   pip = (struct ip *)MBUF_CTOP(bp);
  83   if (*proto == PROTO_IP && pip->ip_p == IPPROTO_TCP &&
  84       cproto == PROTO_VJCOMP) {
  85     type = sl_compress_tcp(bp, pip, &bundle->ncp.ipcp.vj.cslc,
  86                            &bundle->ncp.ipcp.vj.slstat,
  87                            bundle->ncp.ipcp.peer_compproto & 0xff);
  88     log_Printf(LogDEBUG, "vj_LayerWrite: type = %x\n", type);
  89     switch (type) {
  90     case TYPE_IP:
  91       break;
  92
  93     case TYPE_UNCOMPRESSED_TCP:
  94       *proto = PROTO_VJUNCOMP;
  95       log_Printf(LogDEBUG, "vj_LayerPush: PROTO_IP -> PROTO_VJUNCOMP\n");
  96       m_settype(bp, MB_VJOUT);
  97       break;
  98
  99     case TYPE_COMPRESSED_TCP:
 100       *proto = PROTO_VJCOMP;
 101       log_Printf(LogDEBUG, "vj_LayerPush: PROTO_IP -> PROTO_VJUNCOMP\n");
 102       m_settype(bp, MB_VJOUT);
 103       break;
 104
 105     default:
 106       log_Printf(LogERROR, "vj_LayerPush: Unknown frame type %x\n", type);
 107       m_freem(bp);
 108       return NULL;
 109     }
 110   }
 111
 112   return bp;
 113 }
 114
 115 static struct mbuf *
 116 VjUncompressTcp(struct ipcp *ipcp, struct mbuf *bp, u_char type)
 117 {
 118   u_char *bufp;
 119   int len, olen, rlen;
 120   u_char work[MAX_HDR + MAX_VJHEADER];  /* enough to hold TCP/IP header */
 121
 122   bp = m_pullup(bp);
 123   olen = len = m_length(bp);
 124   if (type == TYPE_UNCOMPRESSED_TCP) {
 125     /*
 126      * Uncompressed packet does NOT change its size, so that we can use mbuf
 127      * space for uncompression job.
 128      */
 129     bufp = MBUF_CTOP(bp);
 130     len = sl_uncompress_tcp(&bufp, len, type, &ipcp->vj.cslc, &ipcp->vj.slstat,
 131                             (ipcp->my_compproto >> 8) & 255);
 132     if (len <= 0) {
 133       m_freem(bp);
 134       bp = NULL;
 135     } else
 136       m_settype(bp, MB_VJIN);
 137     return bp;
 138   }
 139
 140   /*
 141    * Handle compressed packet. 1) Read upto MAX_VJHEADER bytes into work
 142    * space. 2) Try to uncompress it. 3) Compute amount of necessary space. 4)
 143    * Copy unread data info there.
 144    */
 145   if (len > MAX_VJHEADER)
 146     len = MAX_VJHEADER;
 147   rlen = len;
 148   bufp = work + MAX_HDR;
 149   bp = mbuf_Read(bp, bufp, rlen);
 150   len = sl_uncompress_tcp(&bufp, olen, type, &ipcp->vj.cslc, &ipcp->vj.slstat,
 151                           (ipcp->my_compproto >> 8) & 255);
 152   if (len <= 0) {
 153     m_freem(bp);
 154     return NULL;
 155   }
 156   len -= olen;
 157   len += rlen;
 158
 159   bp = m_prepend(bp, bufp, len, 0);
 160   m_settype(bp, MB_VJIN);
 161
 162   return bp;
 163 }
 164
 165 static struct mbuf *
 166 vj_LayerPull(struct bundle *bundle, struct link *l __unused, struct mbuf *bp,
 167              u_short *proto)
 168 {
 169   u_char type;
 170
 171   switch (*proto) {
 172   case PROTO_VJCOMP:
 173     type = TYPE_COMPRESSED_TCP;
 174     log_Printf(LogDEBUG, "vj_LayerPull: PROTO_VJCOMP -> PROTO_IP\n");
 175     break;
 176   case PROTO_VJUNCOMP:
 177     type = TYPE_UNCOMPRESSED_TCP;
 178     log_Printf(LogDEBUG, "vj_LayerPull: PROTO_VJUNCOMP -> PROTO_IP\n");
 179     break;
 180   default:
 181     return bp;
 182   }
 183
 184   *proto = PROTO_IP;
 185   return VjUncompressTcp(&bundle->ncp.ipcp, bp, type);
 186 }
 187
 188 const char *
 189 vj2asc(u_int32_t val)
 190 {
 191   static char asc[50];          /* The return value is used immediately */
 192
 193   if (val)
 194     snprintf(asc, sizeof asc, "%d VJ slots with%s slot compression",
 195             (int)((val>>8)&15)+1, val & 1 ?  "" : "out");
 196   else
 197     strcpy(asc, "VJ disabled");
 198   return asc;
 199 }
 200
 201 struct layer vjlayer = { LAYER_VJ, "vj", vj_LayerPush, vj_LayerPull };