1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 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. 15 * 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 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/types.h> 30 31 #include <stdio.h> 32 #include <termios.h> 33 34 #include "defs.h" 35 #include "layer.h" 36 #include "timer.h" 37 #include "fsm.h" 38 #include "log.h" 39 #include "mbuf.h" 40 #include "acf.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 #include "descriptor.h" 49 #include "async.h" 50 #include "physical.h" 51 52 int 53 acf_WrapperOctets(struct lcp *lcp, u_short proto) 54 { 55 return (proto == PROTO_LCP || lcp->his_acfcomp == 0) ? 2 : 0; 56 } 57 58 static struct mbuf * 59 acf_LayerPush(struct bundle *b __unused, struct link *l, struct mbuf *bp, 60 int pri __unused, u_short *proto) 61 { 62 const u_char cp[2] = { HDLC_ADDR, HDLC_UI }; 63 64 if (*proto == PROTO_LCP || l->lcp.his_acfcomp == 0) { 65 bp = m_prepend(bp, cp, 2, 0); 66 m_settype(bp, MB_ACFOUT); 67 } 68 69 return bp; 70 } 71 72 static struct mbuf * 73 acf_LayerPull(struct bundle *b __unused, struct link *l, struct mbuf *bp, 74 u_short *proto __unused) 75 { 76 struct physical *p = link2physical(l); 77 u_char cp[2]; 78 79 if (!p) { 80 log_Printf(LogERROR, "Can't Pull an acf packet from a logical link\n"); 81 return bp; 82 } 83 84 if (mbuf_View(bp, cp, 2) == 2) { 85 if (!p->link.lcp.want_acfcomp) { 86 /* We expect the packet not to be compressed */ 87 bp = mbuf_Read(bp, cp, 2); 88 if (cp[0] != HDLC_ADDR) { 89 p->hdlc.lqm.ifInErrors++; 90 p->hdlc.stats.badaddr++; 91 log_Printf(LogDEBUG, "acf_LayerPull: addr 0x%02x\n", cp[0]); 92 m_freem(bp); 93 return NULL; 94 } 95 if (cp[1] != HDLC_UI) { 96 p->hdlc.lqm.ifInErrors++; 97 p->hdlc.stats.badcommand++; 98 log_Printf(LogDEBUG, "acf_LayerPull: control 0x%02x\n", cp[1]); 99 m_freem(bp); 100 return NULL; 101 } 102 m_settype(bp, MB_ACFIN); 103 } else if (cp[0] == HDLC_ADDR && cp[1] == HDLC_UI) { 104 /* 105 * We can receive compressed packets, but the peer still sends 106 * uncompressed packets (or maybe this is a PROTO_LCP packet) ! 107 */ 108 bp = mbuf_Read(bp, cp, 2); 109 m_settype(bp, MB_ACFIN); 110 } 111 } 112 113 return bp; 114 } 115 116 struct layer acflayer = { LAYER_ACF, "acf", acf_LayerPush, acf_LayerPull }; 117