/* $OpenBSD: print-llc.c,v 1.16 2006/05/29 17:38:46 moritz Exp $ */ /* * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that: (1) source code distributions * retain the above copyright notice and this paragraph in its entirety, (2) * distributions including binary code include the above copyright notice and * this paragraph in its entirety in the documentation or other materials * provided with the distribution, and (3) all advertising materials mentioning * features or use of this software display the following acknowledgement: * ``This product includes software developed by the University of California, * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of * the University nor the names of its contributors may be used to endorse * or promote products derived from this software without specific prior * written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. * * Code by Matt Thomas, Digital Equipment Corporation * with an awful lot of hacking by Jeffrey Mogul, DECWRL */ #ifndef lint static const char rcsid[] = "@(#) $Header: /cvs/OpenBSD/src/usr.sbin/tcpdump/print-llc.c,v 1.16 2006/05/29 17:38:46 moritz Exp $"; #endif #include #include #include #include #include #include #include #include #include "interface.h" #include "addrtoname.h" #include "extract.h" /* must come after interface.h */ #include "ethertype.h" #include "llc.h" static struct tok cmd2str[] = { { LLC_UI, "ui" }, { LLC_TEST, "test" }, { LLC_XID, "xid" }, { LLC_UA, "ua" }, { LLC_DISC, "disc" }, { LLC_DM, "dm" }, { LLC_SABME, "sabme" }, { LLC_FRMR, "frmr" }, { 0, NULL } }; /* * Returns non-zero IFF it succeeds in printing the header */ int llc_print(const u_char *p, u_int length, u_int caplen, const u_char *esrc, const u_char *edst) { struct llc llc; register u_short et; #if 0 u_short control; #endif register int ret; if (caplen < 3) { (void)printf("[|llc]"); default_print((u_char *)p, caplen); return(0); } /* Watch out for possible alignment problems */ memcpy((char *)&llc, (char *)p, min(caplen, sizeof(llc))); if (llc.ssap == LLCSAP_GLOBAL && llc.dsap == LLCSAP_GLOBAL) { ipx_print(p, length); return (1); } #ifdef notyet else if (p[0] == 0xf0 && p[1] == 0xf0) netbios_print(p, length); #endif if (llc.ssap == LLCSAP_ISONS && llc.dsap == LLCSAP_ISONS && llc.llcui == LLC_UI) { isoclns_print(p + 3, length - 3, caplen - 3, esrc, edst); return (1); } if (llc.ssap == LLCSAP_SNAP && llc.dsap == LLCSAP_SNAP && llc.llcui == LLC_UI) { if (caplen < sizeof(llc)) { (void)printf("[|llc-snap]"); default_print((u_char *)p, caplen); return (0); } /* Cisco Discovery Protocol - SNAP & ether type 0x2000 */ if (llc.ethertype[0] == 0x20 && llc.ethertype[1] == 0x00) { cdp_print(p, length, caplen, esrc, edst); return (1); } /* Shared Spanning Tree Protocol - SNAP & ether type 0x010b */ if (llc.ethertype[0] == 0x01 && llc.ethertype[1] == 0x0b) { stp_print(p, length); return (1); } if (vflag) (void)printf("snap %s ", protoid_string(llc.llcpi)); caplen -= sizeof(llc); length -= sizeof(llc); p += sizeof(llc); /* This is an encapsulated Ethernet packet */ et = EXTRACT_16BITS(&llc.ethertype[0]); /* * Some protocols have special handling if they are 802.3 * SNAP encapsulated vs vers II encapsulated. Handle * those special protocols here, and hand the rest to * print-ether.c so we don't have to duplicate * all that code here. */ switch (et) { case ETHERTYPE_ATALK: atalk_print(p, length); ret = 1; break; default: ret = ether_encap_print(et, p, length, caplen); break; } if (ret) return (ret); } if (llc.ssap == LLCSAP_8021D && llc.dsap == LLCSAP_8021D) { stp_print(p, length); return (1); } #if 0 if (llc.ssap == 0xf0 && llc.dsap == 0xf0) { /* * we don't actually have a full netbeui parser yet, but the * smb parser can handle many smb-in-netbeui packets, which * is very useful, so we call that */ /* * Skip the DSAP and LSAP. */ p += 2; length -= 2; caplen -= 2; /* * OK, what type of LLC frame is this? The length * of the control field depends on that - S or I * frames have a two-byte control field, and U frames * have a one-byte control field. */ if ((llc.llcu & LLC_U_FMT) == LLC_U_FMT) { control = llc.llcu; p += 1; length -= 1; caplen -= 1; } else { control = llc.llcis; p += 2; length -= 2; caplen -= 2; } netbeui_print(control, p, p + min(caplen, length)); return (1); } #endif if ((llc.ssap & ~LLC_GSAP) == llc.dsap) { if (eflag) (void)printf("%s ", llcsap_string(llc.dsap)); else (void)printf("%s > %s %s ", etheraddr_string(esrc), etheraddr_string(edst), llcsap_string(llc.dsap)); } else { if (eflag) (void)printf("%s > %s ", llcsap_string(llc.ssap & ~LLC_GSAP), llcsap_string(llc.dsap)); else (void)printf("%s %s > %s %s ", etheraddr_string(esrc), llcsap_string(llc.ssap & ~LLC_GSAP), etheraddr_string(edst), llcsap_string(llc.dsap)); } if ((llc.llcu & LLC_U_FMT) == LLC_U_FMT) { const char *m; char f; m = tok2str(cmd2str, "%02x", LLC_U_CMD(llc.llcu)); switch ((llc.ssap & LLC_GSAP) | (llc.llcu & LLC_U_POLL)) { case 0: f = 'C'; break; case LLC_GSAP: f = 'R'; break; case LLC_U_POLL: f = 'P'; break; case LLC_GSAP|LLC_U_POLL: f = 'F'; break; default: f = '?'; break; } printf("%s/%c", m, f); if (caplen < 6) { default_print_unaligned(p, caplen); return (0); } p += 3; length -= 3; caplen -= 3; if ((llc.llcu & ~LLC_U_POLL) == LLC_XID) { if (*p == LLC_XID_FI) { printf(": %02x %02x", p[1], p[2]); p += 3; length -= 3; caplen -= 3; } } #if 0 if (!strcmp(m,"ui") && f=='C') { /* * we don't have a proper ipx decoder yet, but there * is a partial one in the smb code */ ipx_netbios_print(p,p+min(caplen,length)); } #endif } else { char f; if (caplen < 4) { default_print_unaligned(p, caplen); return (0); } llc.llcis = ntohs(llc.llcis); switch ((llc.ssap & LLC_GSAP) | (llc.llcu & LLC_U_POLL)) { case 0: f = 'C'; break; case LLC_GSAP: f = 'R'; break; case LLC_U_POLL: f = 'P'; break; case LLC_GSAP|LLC_U_POLL: f = 'F'; break; default: f = '?'; break; } if ((llc.llcu & LLC_S_FMT) == LLC_S_FMT) { static char *llc_s[] = { "rr", "rej", "rnr", "03" }; (void)printf("%s (r=%d,%c)", llc_s[LLC_S_CMD(llc.llcis)], LLC_IS_NR(llc.llcis), f); } else { (void)printf("I (s=%d,r=%d,%c)", LLC_I_NS(llc.llcis), LLC_IS_NR(llc.llcis), f); } p += 4; length -= 4; caplen -= 4; } (void)printf(" len=%d", length); return(1); }