1 /* 2 * Input/Output VJ Compressed packets 3 * 4 * Written by Toshiharu OHNO (tony-o@iij.ad.jp) 5 * 6 * Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd. 7 * 8 * Redistribution and use in source and binary forms are permitted 9 * provided that the above copyright notice and this paragraph are 10 * duplicated in all such forms and that any documentation, 11 * advertising materials, and other materials related to such 12 * distribution and use acknowledge that the software was developed 13 * by the Internet Initiative Japan, Inc. The name of the 14 * IIJ may not be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 * 20 * $Id: vjcomp.c,v 1.22 1998/08/07 18:42:51 brian Exp $ 21 * 22 * TODO: 23 */ 24 #include <sys/types.h> 25 #include <netinet/in.h> 26 #include <netinet/in_systm.h> 27 #include <netinet/ip.h> 28 #include <sys/un.h> 29 30 #include <stdio.h> 31 #include <string.h> 32 33 #include "mbuf.h" 34 #include "log.h" 35 #include "timer.h" 36 #include "fsm.h" 37 #include "lcpproto.h" 38 #include "slcompress.h" 39 #include "lqr.h" 40 #include "hdlc.h" 41 #include "defs.h" 42 #include "iplist.h" 43 #include "throughput.h" 44 #include "ipcp.h" 45 #include "lcp.h" 46 #include "ccp.h" 47 #include "link.h" 48 #include "filter.h" 49 #include "descriptor.h" 50 #include "mp.h" 51 #include "bundle.h" 52 #include "vjcomp.h" 53 54 #define MAX_VJHEADER 16 /* Maximum size of compressed header */ 55 56 void 57 vj_SendFrame(struct link *l, struct mbuf * bp, struct bundle *bundle) 58 { 59 int type; 60 u_short proto; 61 u_short cproto = bundle->ncp.ipcp.peer_compproto >> 16; 62 63 log_Printf(LogDEBUG, "vj_SendFrame: COMPPROTO = %x\n", 64 bundle->ncp.ipcp.peer_compproto); 65 if (((struct ip *) MBUF_CTOP(bp))->ip_p == IPPROTO_TCP 66 && cproto == PROTO_VJCOMP) { 67 type = sl_compress_tcp(bp, (struct ip *)MBUF_CTOP(bp), 68 &bundle->ncp.ipcp.vj.cslc, 69 &bundle->ncp.ipcp.vj.slstat, 70 bundle->ncp.ipcp.peer_compproto & 0xff); 71 log_Printf(LogDEBUG, "vj_SendFrame: type = %x\n", type); 72 switch (type) { 73 case TYPE_IP: 74 proto = PROTO_IP; 75 break; 76 case TYPE_UNCOMPRESSED_TCP: 77 proto = PROTO_VJUNCOMP; 78 break; 79 case TYPE_COMPRESSED_TCP: 80 proto = PROTO_VJCOMP; 81 break; 82 default: 83 log_Printf(LogALERT, "Unknown frame type %x\n", type); 84 mbuf_Free(bp); 85 return; 86 } 87 } else 88 proto = PROTO_IP; 89 90 if (!ccp_Compress(&l->ccp, l, PRI_NORMAL, proto, bp)) 91 hdlc_Output(l, PRI_NORMAL, proto, bp); 92 } 93 94 static struct mbuf * 95 VjUncompressTcp(struct ipcp *ipcp, struct mbuf * bp, u_char type) 96 { 97 u_char *bufp; 98 int len, olen, rlen; 99 struct mbuf *nbp; 100 u_char work[MAX_HDR + MAX_VJHEADER]; /* enough to hold TCP/IP header */ 101 102 olen = len = mbuf_Length(bp); 103 if (type == TYPE_UNCOMPRESSED_TCP) { 104 105 /* 106 * Uncompressed packet does NOT change its size, so that we can use mbuf 107 * space for uncompression job. 108 */ 109 bufp = MBUF_CTOP(bp); 110 len = sl_uncompress_tcp(&bufp, len, type, &ipcp->vj.cslc, &ipcp->vj.slstat, 111 (ipcp->my_compproto >> 8) & 255); 112 if (len <= 0) { 113 mbuf_Free(bp); 114 bp = NULL; 115 } 116 return (bp); 117 } 118 119 /* 120 * Handle compressed packet. 1) Read upto MAX_VJHEADER bytes into work 121 * space. 2) Try to uncompress it. 3) Compute amount of necesary space. 4) 122 * Copy unread data info there. 123 */ 124 if (len > MAX_VJHEADER) 125 len = MAX_VJHEADER; 126 rlen = len; 127 bufp = work + MAX_HDR; 128 bp = mbuf_Read(bp, bufp, rlen); 129 len = sl_uncompress_tcp(&bufp, olen, type, &ipcp->vj.cslc, &ipcp->vj.slstat, 130 (ipcp->my_compproto >> 8) & 255); 131 if (len <= 0) { 132 mbuf_Free(bp); 133 return NULL; 134 } 135 len -= olen; 136 len += rlen; 137 nbp = mbuf_Alloc(len, MB_VJCOMP); 138 memcpy(MBUF_CTOP(nbp), bufp, len); 139 nbp->next = bp; 140 return (nbp); 141 } 142 143 struct mbuf * 144 vj_Input(struct ipcp *ipcp, struct mbuf *bp, int proto) 145 { 146 u_char type; 147 148 log_Printf(LogDEBUG, "vj_Input: proto %02x\n", proto); 149 log_DumpBp(LogDEBUG, "Raw packet info:", bp); 150 151 switch (proto) { 152 case PROTO_VJCOMP: 153 type = TYPE_COMPRESSED_TCP; 154 break; 155 case PROTO_VJUNCOMP: 156 type = TYPE_UNCOMPRESSED_TCP; 157 break; 158 default: 159 log_Printf(LogWARN, "vj_Input...???\n"); 160 return (bp); 161 } 162 bp = VjUncompressTcp(ipcp, bp, type); 163 return (bp); 164 } 165 166 const char * 167 vj2asc(u_int32_t val) 168 { 169 static char asc[50]; /* The return value is used immediately */ 170 171 if (val) 172 snprintf(asc, sizeof asc, "%d VJ slots %s slot compression", 173 (int)((val>>8)&15)+1, val & 1 ? "with" : "without"); 174 else 175 strcpy(asc, "VJ disabled"); 176 return asc; 177 } 178