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)
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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
31 #include <sys/param.h>
32 #include <netinet/in.h>
33 #include <netinet/in_systm.h>
34 #include <netinet/ip.h>
35 #include <sys/socket.h>
39 #include <string.h> /* strlen/memcpy */
48 #include "slcompress.h"
53 #include "throughput.h"
61 #include "descriptor.h"
71 #define MAX_VJHEADER 16 /* Maximum size of compressed header */
74 vj_LayerPush(struct bundle *bundle, struct link *l, struct mbuf *bp, int pri,
79 u_short cproto = bundle->ncp.ipcp.peer_compproto >> 16;
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);
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);
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);
106 log_Printf(LogERROR, "vj_LayerPush: Unknown frame type %x\n", type);
116 VjUncompressTcp(struct ipcp *ipcp, struct mbuf *bp, u_char type)
120 u_char work[MAX_HDR + MAX_VJHEADER]; /* enough to hold TCP/IP header */
123 olen = len = m_length(bp);
124 if (type == TYPE_UNCOMPRESSED_TCP) {
126 * Uncompressed packet does NOT change its size, so that we can use mbuf
127 * space for uncompression job.
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);
136 m_settype(bp, MB_VJIN);
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.
145 if (len > MAX_VJHEADER)
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);
159 bp = m_prepend(bp, bufp, len, 0);
160 m_settype(bp, MB_VJIN);
166 vj_LayerPull(struct bundle *bundle, struct link *l, struct mbuf *bp,
173 type = TYPE_COMPRESSED_TCP;
174 log_Printf(LogDEBUG, "vj_LayerPull: PROTO_VJCOMP -> PROTO_IP\n");
177 type = TYPE_UNCOMPRESSED_TCP;
178 log_Printf(LogDEBUG, "vj_LayerPull: PROTO_VJUNCOMP -> PROTO_IP\n");
185 return VjUncompressTcp(&bundle->ncp.ipcp, bp, type);
189 vj2asc(u_int32_t val)
191 static char asc[50]; /* The return value is used immediately */
194 snprintf(asc, sizeof asc, "%d VJ slots with%s slot compression",
195 (int)((val>>8)&15)+1, val & 1 ? "" : "out");
197 strcpy(asc, "VJ disabled");
201 struct layer vjlayer = { LAYER_VJ, "vj", vj_LayerPush, vj_LayerPull };