usr.sbin/ppp/acf.c

   1 /*-
   2  * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/usr.sbin/ppp/acf.c,v 1.4.2.1 2000/08/19 09:29:59 brian Exp $
  27  * $DragonFly: src/usr.sbin/ppp/acf.c,v 1.3 2008/05/19 10:19:49 corecode Exp $
  28  */
  29
  30 #include <sys/types.h>
  31 #include <sys/select.h>
  32
  33 #include <stdio.h>
  34 #include <termios.h>
  35
  36 #include "defs.h"
  37 #include "layer.h"
  38 #include "timer.h"
  39 #include "fsm.h"
  40 #include "log.h"
  41 #include "mbuf.h"
  42 #include "acf.h"
  43 #include "proto.h"
  44 #include "throughput.h"
  45 #include "lqr.h"
  46 #include "hdlc.h"
  47 #include "lcp.h"
  48 #include "ccp.h"
  49 #include "link.h"
  50 #include "descriptor.h"
  51 #include "async.h"
  52 #include "physical.h"
  53
  54 int
  55 acf_WrapperOctets(struct lcp *lcp, u_short proto)
  56 {
  57   return (proto == PROTO_LCP || lcp->his_acfcomp == 0) ? 2 : 0;
  58 }
  59
  60 static struct mbuf *
  61 acf_LayerPush(struct bundle *b, struct link *l, struct mbuf *bp,
  62               int pri, u_short *proto)
  63 {
  64   const u_char cp[2] = { HDLC_ADDR, HDLC_UI };
  65
  66   if (*proto == PROTO_LCP || l->lcp.his_acfcomp == 0) {
  67     bp = m_prepend(bp, cp, 2, 0);
  68     m_settype(bp, MB_ACFOUT);
  69   }
  70
  71   return bp;
  72 }
  73
  74 static struct mbuf *
  75 acf_LayerPull(struct bundle *b, struct link *l, struct mbuf *bp, u_short *proto)
  76 {
  77   struct physical *p = link2physical(l);
  78   u_char cp[2];
  79
  80   if (!p) {
  81     log_Printf(LogERROR, "Can't Pull an acf packet from a logical link\n");
  82     return bp;
  83   }
  84
  85   if (mbuf_View(bp, cp, 2) == 2) {
  86     if (!p->link.lcp.want_acfcomp) {
  87       /* We expect the packet not to be compressed */
  88       bp = mbuf_Read(bp, cp, 2);
  89       if (cp[0] != HDLC_ADDR) {
  90         p->hdlc.lqm.SaveInErrors++;
  91         p->hdlc.stats.badaddr++;
  92         log_Printf(LogDEBUG, "acf_LayerPull: addr 0x%02x\n", cp[0]);
  93         m_freem(bp);
  94         return NULL;
  95       }
  96       if (cp[1] != HDLC_UI) {
  97         p->hdlc.lqm.SaveInErrors++;
  98         p->hdlc.stats.badcommand++;
  99         log_Printf(LogDEBUG, "acf_LayerPull: control 0x%02x\n", cp[1]);
 100         m_freem(bp);
 101         return NULL;
 102       }
 103       m_settype(bp, MB_ACFIN);
 104     } else if (cp[0] == HDLC_ADDR && cp[1] == HDLC_UI) {
 105       /*
 106        * We can receive compressed packets, but the peer still sends
 107        * uncompressed packets (or maybe this is a PROTO_LCP packet) !
 108        */
 109       bp = mbuf_Read(bp, cp, 2);
 110       m_settype(bp, MB_ACFIN);
 111     }
 112   }
 113
 114   return bp;
 115 }
 116
 117 struct layer acflayer = { LAYER_ACF, "acf", acf_LayerPush, acf_LayerPull };