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 * $FreeBSD$
27 */
28
29#include <sys/types.h>
30
31#include <stdio.h>
32#include <termios.h>
33
34#include "layer.h"
35#include "acf.h"
36#include "defs.h"
37#include "log.h"
38#include "timer.h"
39#include "fsm.h"
40#include "mbuf.h"
41#include "proto.h"
42#include "throughput.h"
43#include "lqr.h"
44#include "hdlc.h"
45#include "lcp.h"
46#include "ccp.h"
47#include "link.h"
48
49int
50proto_WrapperOctets(struct lcp *lcp, u_short proto)
51{
52  return (lcp->his_protocomp && !(proto & 0xff00)) ? 1 : 2;
53}
54
55struct mbuf *
56proto_Prepend(struct mbuf *bp, u_short proto, unsigned comp, int extra)
57{
58  u_char cp[2];
59
60  cp[0] = proto >> 8;
61  cp[1] = proto & 0xff;
62
63  if (comp && cp[0] == 0)
64    bp = m_prepend(bp, cp + 1, 1, extra);
65  else
66    bp = m_prepend(bp, cp, 2, extra);
67
68  return bp;
69}
70
71static struct mbuf *
72proto_LayerPush(struct bundle *b __unused, struct link *l, struct mbuf *bp,
73                int pri __unused, u_short *proto)
74{
75  log_Printf(LogDEBUG, "proto_LayerPush: Using 0x%04x\n", *proto);
76  bp = proto_Prepend(bp, *proto, l->lcp.his_protocomp,
77                     acf_WrapperOctets(&l->lcp, *proto));
78  m_settype(bp, MB_PROTOOUT);
79  link_ProtocolRecord(l, *proto, PROTO_OUT);
80
81  return bp;
82}
83
84static struct mbuf *
85proto_LayerPull(struct bundle *b __unused, struct link *l, struct mbuf *bp,
86                u_short *proto)
87{
88  u_char cp[2];
89  size_t got;
90
91  if ((got = mbuf_View(bp, cp, 2)) == 0) {
92    m_freem(bp);
93    return NULL;
94  }
95
96  *proto = cp[0];
97  if (!(*proto & 1)) {
98    if (got == 1) {
99      m_freem(bp);
100      return NULL;
101    }
102    bp = mbuf_Read(bp, cp, 2);
103    *proto = (*proto << 8) | cp[1];
104  } else
105    bp = mbuf_Read(bp, cp, 1);
106
107  log_Printf(LogDEBUG, "proto_LayerPull: unknown -> 0x%04x\n", *proto);
108  m_settype(bp, MB_PROTOIN);
109  link_ProtocolRecord(l, *proto, PROTO_IN);
110
111  return bp;
112}
113
114struct layer protolayer =
115  { LAYER_PROTO, "proto", proto_LayerPush, proto_LayerPull };
116