usr.sbin/ppp/proto.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/proto.c,v 1.5.2.1 2000/08/19 09:30:08 brian Exp $
  27  * $DragonFly: src/usr.sbin/ppp/proto.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 "layer.h"
  37 #include "acf.h"
  38 #include "defs.h"
  39 #include "log.h"
  40 #include "timer.h"
  41 #include "fsm.h"
  42 #include "mbuf.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
  51 int
  52 proto_WrapperOctets(struct lcp *lcp, u_short proto)
  53 {
  54   return (lcp->his_protocomp && !(proto & 0xff00)) ? 1 : 2;
  55 }
  56
  57 struct mbuf *
  58 proto_Prepend(struct mbuf *bp, u_short proto, unsigned comp, int extra)
  59 {
  60   u_char cp[2];
  61
  62   cp[0] = proto >> 8;
  63   cp[1] = proto & 0xff;
  64
  65   if (comp && cp[0] == 0)
  66     bp = m_prepend(bp, cp + 1, 1, extra);
  67   else
  68     bp = m_prepend(bp, cp, 2, extra);
  69
  70   return bp;
  71 }
  72
  73 static struct mbuf *
  74 proto_LayerPush(struct bundle *b, struct link *l, struct mbuf *bp,
  75                 int pri, u_short *proto)
  76 {
  77   log_Printf(LogDEBUG, "proto_LayerPush: Using 0x%04x\n", *proto);
  78   bp = proto_Prepend(bp, *proto, l->lcp.his_protocomp,
  79                      acf_WrapperOctets(&l->lcp, *proto));
  80   m_settype(bp, MB_PROTOOUT);
  81   link_ProtocolRecord(l, *proto, PROTO_OUT);
  82
  83   return bp;
  84 }
  85
  86 static struct mbuf *
  87 proto_LayerPull(struct bundle *b, struct link *l, struct mbuf *bp,
  88                 u_short *proto)
  89 {
  90   u_char cp[2];
  91   size_t got;
  92
  93   if ((got = mbuf_View(bp, cp, 2)) == 0) {
  94     m_freem(bp);
  95     return NULL;
  96   }
  97
  98   *proto = cp[0];
  99   if (!(*proto & 1)) {
 100     if (got == 1) {
 101       m_freem(bp);
 102       return NULL;
 103     }
 104     bp = mbuf_Read(bp, cp, 2);
 105     *proto = (*proto << 8) | cp[1];
 106   } else
 107     bp = mbuf_Read(bp, cp, 1);
 108
 109   log_Printf(LogDEBUG, "proto_LayerPull: unknown -> 0x%04x\n", *proto);
 110   m_settype(bp, MB_PROTOIN);
 111   link_ProtocolRecord(l, *proto, PROTO_IN);
 112
 113   return bp;
 114 }
 115
 116 struct layer protolayer =
 117   { LAYER_PROTO, "proto", proto_LayerPush, proto_LayerPull };