vjcomp.c revision 30715
1243791Sdim/* 2243791Sdim * Input/Output VJ Compressed packets 3243791Sdim * 4243791Sdim * Written by Toshiharu OHNO (tony-o@iij.ad.jp) 5243791Sdim * 6243791Sdim * Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd. 7243791Sdim * 8243791Sdim * Redistribution and use in source and binary forms are permitted 9243791Sdim * provided that the above copyright notice and this paragraph are 10243791Sdim * duplicated in all such forms and that any documentation, 11243791Sdim * advertising materials, and other materials related to such 12243791Sdim * distribution and use acknowledge that the software was developed 13243791Sdim * by the Internet Initiative Japan, Inc. The name of the 14243791Sdim * IIJ may not be used to endorse or promote products derived 15243791Sdim * from this software without specific prior written permission. 16243791Sdim * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17243791Sdim * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18243791Sdim * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19243791Sdim * 20243791Sdim * $Id: vjcomp.c,v 1.10 1997/10/07 00:56:58 brian Exp $ 21243791Sdim * 22243791Sdim * TODO: 23243791Sdim */ 24243791Sdim#include <sys/types.h> 25243791Sdim#include <netinet/in.h> 26243791Sdim#include <netinet/in_systm.h> 27243791Sdim#include <netinet/ip.h> 28243791Sdim 29243791Sdim#include <string.h> 30243791Sdim 31243791Sdim#include "mbuf.h" 32243791Sdim#include "log.h" 33243791Sdim#include "defs.h" 34243791Sdim#include "timer.h" 35243791Sdim#include "fsm.h" 36243791Sdim#include "lcpproto.h" 37243791Sdim#include "slcompress.h" 38243791Sdim#include "hdlc.h" 39243791Sdim#include "ipcp.h" 40243791Sdim#include "vjcomp.h" 41243791Sdim 42243791Sdim#define MAX_VJHEADER 16 /* Maximum size of compressed header */ 43263508Sdim 44243791Sdimstruct slcompress cslc; 45263508Sdim 46243791Sdimvoid 47243791SdimVjInit(int max_state) 48243791Sdim{ 49243791Sdim sl_compress_init(&cslc, max_state); 50249423Sdim} 51249423Sdim 52263508Sdimvoid 53263508SdimSendPppFrame(struct mbuf * bp) 54263508Sdim{ 55249423Sdim int type; 56249423Sdim int proto; 57249423Sdim int cproto = IpcpInfo.his_compproto >> 16; 58243791Sdim 59243791Sdim LogPrintf(LogDEBUG, "SendPppFrame: proto = %x\n", IpcpInfo.his_compproto); 60243791Sdim if (((struct ip *) MBUF_CTOP(bp))->ip_p == IPPROTO_TCP 61243791Sdim && cproto == PROTO_VJCOMP) { 62243791Sdim type = sl_compress_tcp(bp, (struct ip *) MBUF_CTOP(bp), &cslc, IpcpInfo.his_compproto & 0xff); 63243791Sdim 64243791Sdim LogPrintf(LogDEBUG, "SendPppFrame: type = %x\n", type); 65243791Sdim switch (type) { 66243791Sdim case TYPE_IP: 67243791Sdim proto = PROTO_IP; 68243791Sdim break; 69243791Sdim case TYPE_UNCOMPRESSED_TCP: 70243791Sdim proto = PROTO_VJUNCOMP; 71243791Sdim break; 72243791Sdim case TYPE_COMPRESSED_TCP: 73243791Sdim proto = PROTO_VJCOMP; 74243791Sdim break; 75243791Sdim default: 76243791Sdim LogPrintf(LogERROR, "Unknown frame type %x\n", type); 77243791Sdim pfree(bp); 78243791Sdim return; 79243791Sdim } 80243791Sdim } else 81243791Sdim proto = PROTO_IP; 82243791Sdim HdlcOutput(PRI_NORMAL, proto, bp); 83243791Sdim} 84243791Sdim 85243791Sdimstatic struct mbuf * 86243791SdimVjUncompressTcp(struct mbuf * bp, u_char type) 87243791Sdim{ 88243791Sdim u_char *bufp; 89243791Sdim int len, olen, rlen; 90243791Sdim struct mbuf *nbp; 91243791Sdim u_char work[MAX_HDR + MAX_VJHEADER]; /* enough to hold TCP/IP header */ 92243791Sdim 93243791Sdim olen = len = plength(bp); 94243791Sdim if (type == TYPE_UNCOMPRESSED_TCP) { 95243791Sdim 96243791Sdim /* 97243791Sdim * Uncompressed packet does NOT change its size, so that we can use mbuf 98243791Sdim * space for uncompression job. 99243791Sdim */ 100243791Sdim bufp = MBUF_CTOP(bp); 101243791Sdim len = sl_uncompress_tcp(&bufp, len, type, &cslc); 102243791Sdim if (len <= 0) { 103243791Sdim pfree(bp); 104243791Sdim bp = NULLBUFF; 105243791Sdim } 106243791Sdim return (bp); 107243791Sdim } 108243791Sdim 109243791Sdim /* 110243791Sdim * Handle compressed packet. 1) Read upto MAX_VJHEADER bytes into work 111243791Sdim * space. 2) Try to uncompress it. 3) Compute amount of necesary space. 4) 112243791Sdim * Copy unread data info there. 113243791Sdim */ 114243791Sdim if (len > MAX_VJHEADER) 115243791Sdim len = MAX_VJHEADER; 116243791Sdim rlen = len; 117243791Sdim bufp = work + MAX_HDR; 118243791Sdim bp = mbread(bp, bufp, rlen); 119243791Sdim len = sl_uncompress_tcp(&bufp, olen, type, &cslc); 120243791Sdim if (len <= 0) { 121243791Sdim pfree(bp); 122243791Sdim return NULLBUFF; 123243791Sdim } 124243791Sdim len -= olen; 125243791Sdim len += rlen; 126243791Sdim nbp = mballoc(len, MB_VJCOMP); 127243791Sdim memcpy(MBUF_CTOP(nbp), bufp, len); 128243791Sdim nbp->next = bp; 129243791Sdim return (nbp); 130243791Sdim} 131243791Sdim 132243791Sdimstruct mbuf * 133243791SdimVjCompInput(struct mbuf * bp, int proto) 134243791Sdim{ 135243791Sdim u_char type; 136243791Sdim 137243791Sdim LogPrintf(LogDEBUG, "VjCompInput: proto %02x\n", proto); 138243791Sdim LogDumpBp(LogDEBUG, "Raw packet info:", bp); 139243791Sdim 140243791Sdim switch (proto) { 141243791Sdim case PROTO_VJCOMP: 142243791Sdim type = TYPE_COMPRESSED_TCP; 143243791Sdim break; 144243791Sdim case PROTO_VJUNCOMP: 145243791Sdim type = TYPE_UNCOMPRESSED_TCP; 146243791Sdim break; 147243791Sdim default: 148243791Sdim LogPrintf(LogERROR, "VjCompInput...???\n"); 149243791Sdim return (bp); 150263508Sdim } 151243791Sdim bp = VjUncompressTcp(bp, type); 152243791Sdim return (bp); 153243791Sdim} 154243791Sdim