1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
5 *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
6 *                           Internet Initiative Japan, Inc (IIJ)
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $FreeBSD$
31 */
32
33#include <sys/param.h>
34#include <netinet/in.h>
35#include <netinet/in_systm.h>
36#include <netinet/ip.h>
37#include <sys/socket.h>
38#include <sys/un.h>
39
40#include <stdio.h>
41#include <string.h>		/* strlen/memcpy */
42#include <termios.h>
43
44#include "layer.h"
45#include "mbuf.h"
46#include "log.h"
47#include "timer.h"
48#include "fsm.h"
49#include "proto.h"
50#include "slcompress.h"
51#include "lqr.h"
52#include "hdlc.h"
53#include "defs.h"
54#include "iplist.h"
55#include "throughput.h"
56#include "ncpaddr.h"
57#include "ipcp.h"
58#include "lcp.h"
59#include "ccp.h"
60#include "link.h"
61#include "filter.h"
62#include "descriptor.h"
63#include "mp.h"
64#ifndef NORADIUS
65#include "radius.h"
66#endif
67#include "ipv6cp.h"
68#include "ncp.h"
69#include "bundle.h"
70#include "vjcomp.h"
71
72#define MAX_VJHEADER 16		/* Maximum size of compressed header */
73
74static struct mbuf *
75vj_LayerPush(struct bundle *bundle, struct link *l __unused, struct mbuf *bp,
76	     int pri __unused, u_short *proto)
77{
78  int type;
79  struct ip *pip;
80  u_short cproto = bundle->ncp.ipcp.peer_compproto >> 16;
81
82  bp = m_pullup(bp);
83  pip = (struct ip *)MBUF_CTOP(bp);
84  if (*proto == PROTO_IP && pip->ip_p == IPPROTO_TCP &&
85      cproto == PROTO_VJCOMP) {
86    type = sl_compress_tcp(bp, pip, &bundle->ncp.ipcp.vj.cslc,
87                           &bundle->ncp.ipcp.vj.slstat,
88                           bundle->ncp.ipcp.peer_compproto & 0xff);
89    log_Printf(LogDEBUG, "vj_LayerWrite: type = %x\n", type);
90    switch (type) {
91    case TYPE_IP:
92      break;
93
94    case TYPE_UNCOMPRESSED_TCP:
95      *proto = PROTO_VJUNCOMP;
96      log_Printf(LogDEBUG, "vj_LayerPush: PROTO_IP -> PROTO_VJUNCOMP\n");
97      m_settype(bp, MB_VJOUT);
98      break;
99
100    case TYPE_COMPRESSED_TCP:
101      *proto = PROTO_VJCOMP;
102      log_Printf(LogDEBUG, "vj_LayerPush: PROTO_IP -> PROTO_VJUNCOMP\n");
103      m_settype(bp, MB_VJOUT);
104      break;
105
106    default:
107      log_Printf(LogERROR, "vj_LayerPush: Unknown frame type %x\n", type);
108      m_freem(bp);
109      return NULL;
110    }
111  }
112
113  return bp;
114}
115
116static struct mbuf *
117VjUncompressTcp(struct ipcp *ipcp, struct mbuf *bp, u_char type)
118{
119  u_char *bufp;
120  int len, olen, rlen;
121  u_char work[MAX_HDR + MAX_VJHEADER];	/* enough to hold TCP/IP header */
122
123  bp = m_pullup(bp);
124  olen = len = m_length(bp);
125  if (type == TYPE_UNCOMPRESSED_TCP) {
126    /*
127     * Uncompressed packet does NOT change its size, so that we can use mbuf
128     * space for uncompression job.
129     */
130    bufp = MBUF_CTOP(bp);
131    len = sl_uncompress_tcp(&bufp, len, type, &ipcp->vj.cslc, &ipcp->vj.slstat,
132                            (ipcp->my_compproto >> 8) & 255);
133    if (len <= 0) {
134      m_freem(bp);
135      bp = NULL;
136    } else
137      m_settype(bp, MB_VJIN);
138    return bp;
139  }
140
141  /*
142   * Handle compressed packet. 1) Read up to MAX_VJHEADER bytes into work
143   * space. 2) Try to uncompress it. 3) Compute amount of necessary space. 4)
144   * Copy unread data info there.
145   */
146  if (len > MAX_VJHEADER)
147    len = MAX_VJHEADER;
148  rlen = len;
149  bufp = work + MAX_HDR;
150  bp = mbuf_Read(bp, bufp, rlen);
151  len = sl_uncompress_tcp(&bufp, olen, type, &ipcp->vj.cslc, &ipcp->vj.slstat,
152                          (ipcp->my_compproto >> 8) & 255);
153  if (len <= 0) {
154    m_freem(bp);
155    return NULL;
156  }
157  len -= olen;
158  len += rlen;
159
160  bp = m_prepend(bp, bufp, len, 0);
161  m_settype(bp, MB_VJIN);
162
163  return bp;
164}
165
166static struct mbuf *
167vj_LayerPull(struct bundle *bundle, struct link *l __unused, struct mbuf *bp,
168             u_short *proto)
169{
170  u_char type;
171
172  switch (*proto) {
173  case PROTO_VJCOMP:
174    type = TYPE_COMPRESSED_TCP;
175    log_Printf(LogDEBUG, "vj_LayerPull: PROTO_VJCOMP -> PROTO_IP\n");
176    break;
177  case PROTO_VJUNCOMP:
178    type = TYPE_UNCOMPRESSED_TCP;
179    log_Printf(LogDEBUG, "vj_LayerPull: PROTO_VJUNCOMP -> PROTO_IP\n");
180    break;
181  default:
182    return bp;
183  }
184
185  *proto = PROTO_IP;
186  return VjUncompressTcp(&bundle->ncp.ipcp, bp, type);
187}
188
189const char *
190vj2asc(u_int32_t val)
191{
192  static char asc[50];		/* The return value is used immediately */
193
194  if (val)
195    snprintf(asc, sizeof asc, "%d VJ slots with%s slot compression",
196            (int)((val>>8)&15)+1, val & 1 ?  "" : "out");
197  else
198    strcpy(asc, "VJ disabled");
199  return asc;
200}
201
202struct layer vjlayer = { LAYER_VJ, "vj", vj_LayerPush, vj_LayerPull };
203