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 * $FreeBSD$ 29 */ 30 31 #include <sys/types.h> 32 33 #include <stdio.h> 34 #include <termios.h> 35 36 #include "defs.h" 37 #include "layer.h" 38 #include "timer.h" 39 #include "fsm.h" 40 #include "log.h" 41 #include "mbuf.h" 42 #include "acf.h" 43 #include "proto.h" 44 #include "throughput.h" 45 #include "lqr.h" 46 #include "hdlc.h" 47 #include "lcp.h" 48 #include "ccp.h" 49 #include "link.h" 50 #include "descriptor.h" 51 #include "async.h" 52 #include "physical.h" 53 54 int 55 acf_WrapperOctets(struct lcp *lcp, u_short proto) 56 { 57 return (proto == PROTO_LCP || lcp->his_acfcomp == 0) ? 2 : 0; 58 } 59 60 static struct mbuf * 61 acf_LayerPush(struct bundle *b __unused, struct link *l, struct mbuf *bp, 62 int pri __unused, u_short *proto) 63 { 64 const u_char cp[2] = { HDLC_ADDR, HDLC_UI }; 65 66 if (*proto == PROTO_LCP || l->lcp.his_acfcomp == 0) { 67 bp = m_prepend(bp, cp, 2, 0); 68 m_settype(bp, MB_ACFOUT); 69 } 70 71 return bp; 72 } 73 74 static struct mbuf * 75 acf_LayerPull(struct bundle *b __unused, struct link *l, struct mbuf *bp, 76 u_short *proto __unused) 77 { 78 struct physical *p = link2physical(l); 79 u_char cp[2]; 80 81 if (!p) { 82 log_Printf(LogERROR, "Can't Pull an acf packet from a logical link\n"); 83 return bp; 84 } 85 86 if (mbuf_View(bp, cp, 2) == 2) { 87 if (!p->link.lcp.want_acfcomp) { 88 /* We expect the packet not to be compressed */ 89 bp = mbuf_Read(bp, cp, 2); 90 if (cp[0] != HDLC_ADDR) { 91 p->hdlc.lqm.ifInErrors++; 92 p->hdlc.stats.badaddr++; 93 log_Printf(LogDEBUG, "acf_LayerPull: addr 0x%02x\n", cp[0]); 94 m_freem(bp); 95 return NULL; 96 } 97 if (cp[1] != HDLC_UI) { 98 p->hdlc.lqm.ifInErrors++; 99 p->hdlc.stats.badcommand++; 100 log_Printf(LogDEBUG, "acf_LayerPull: control 0x%02x\n", cp[1]); 101 m_freem(bp); 102 return NULL; 103 } 104 m_settype(bp, MB_ACFIN); 105 } else if (cp[0] == HDLC_ADDR && cp[1] == HDLC_UI) { 106 /* 107 * We can receive compressed packets, but the peer still sends 108 * uncompressed packets (or maybe this is a PROTO_LCP packet) ! 109 */ 110 bp = mbuf_Read(bp, cp, 2); 111 m_settype(bp, MB_ACFIN); 112 } 113 } 114 115 return bp; 116 } 117 118 struct layer acflayer = { LAYER_ACF, "acf", acf_LayerPush, acf_LayerPull }; 119