diff options
| -rw-r--r-- | Makefile.in | 2 | ||||
| -rw-r--r-- | netdissect.h | 1 | ||||
| -rw-r--r-- | print-ether.c | 1 | ||||
| -rw-r--r-- | print-loopback.c | 135 | ||||
| -rw-r--r-- | tests/TESTLIST | 3 | ||||
| -rw-r--r-- | tests/loopback.out | 6 | ||||
| -rw-r--r-- | tests/loopback.pcap | bin | 0 -> 592 bytes |
7 files changed, 147 insertions, 1 deletions
diff --git a/Makefile.in b/Makefile.in index 8e54a98f..7f765847 100644 --- a/Makefile.in +++ b/Makefile.in @@ -85,7 +85,7 @@ LIBNETDISSECT_SRC=addrtoname.c af.c checksum.c cpack.c gmpls.c oui.c gmt2local.c print-igrp.c print-ip.c print-ipcomp.c print-ipfc.c print-ipnet.c \ print-ipx.c print-isakmp.c print-isoclns.c print-juniper.c print-krb.c \ print-l2tp.c print-lane.c print-ldp.c print-lldp.c print-llc.c \ - print-lmp.c print-lspping.c print-lwapp.c \ + print-lmp.c print-loopback.c print-lspping.c print-lwapp.c \ print-lwres.c print-mobile.c print-mpcp.c print-mpls.c print-mptcp.c print-msdp.c \ print-msnlb.c print-nflog.c print-nfs.c print-ntp.c print-null.c \ print-olsr.c print-openflow.c print-openflow-1.0.c print-ospf.c \ diff --git a/netdissect.h b/netdissect.h index d8a6f121..1772f6ec 100644 --- a/netdissect.h +++ b/netdissect.h @@ -309,6 +309,7 @@ extern void ip_print_inner(netdissect_options *ndo, const u_char *bp, u_int length, u_int nh, const u_char *bp2); extern void rrcp_print(netdissect_options *,const u_char *, u_int); +extern void loopback_print(netdissect_options *, const u_char *, u_int); extern void ether_print(netdissect_options *, const u_char *, u_int, u_int, diff --git a/print-ether.c b/print-ether.c index d90a2f16..22808d14 100644 --- a/print-ether.c +++ b/print-ether.c @@ -401,6 +401,7 @@ ethertype_print(netdissect_options *ndo, return (1); case ETHERTYPE_LOOPBACK: + loopback_print(ndo, p, length); return (1); case ETHERTYPE_MPLS: diff --git a/print-loopback.c b/print-loopback.c new file mode 100644 index 00000000..1708033a --- /dev/null +++ b/print-loopback.c @@ -0,0 +1,135 @@ +/* + * This module implements decoding of the the Loopback Protocol, originally + * defined as the Configuration Testing Protocol. It is based on the following + * specification: + * http://www.mit.edu/people/jhawk/ctp.pdf + * + * Copyright (c) 2014 The TCPDUMP project + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <tcpdump-stdinc.h> + +#include "netdissect.h" +#include "extract.h" +#include "ether.h" +#include "addrtoname.h" + +static const char tstr[] = " [|loopback]"; +static const char cstr[] = " (corrupt)"; + +#define LOOPBACK_REPLY 1 +#define LOOPBACK_FWDDATA 2 + +static const struct tok fcode_str[] = { + { LOOPBACK_REPLY, "Reply" }, + { LOOPBACK_FWDDATA, "Forward Data" }, + { 0, NULL } +}; + +static void +loopback_message_print(netdissect_options *ndo, const u_char *cp, const u_int len) +{ + const u_char *ep = cp + len; + uint16_t function; + + if (len < 2) + goto corrupt; + /* function */ + ND_TCHECK2(*cp, 2); + function = EXTRACT_LE_16BITS(cp); + cp += 2; + ND_PRINT((ndo, ", %s", tok2str(fcode_str, " invalid (%u)", function))); + + switch (function) { + case LOOPBACK_REPLY: + if (len < 4) + goto corrupt; + /* receipt number */ + ND_TCHECK2(*cp, 2); + ND_PRINT((ndo, ", receipt number %u", EXTRACT_LE_16BITS(cp))); + cp += 2; + /* data */ + ND_PRINT((ndo, ", data (%u octets)", len - 4)); + ND_TCHECK2(*cp, len - 4); + break; + case LOOPBACK_FWDDATA: + if (len < 8) + goto corrupt; + /* forwarding address */ + ND_TCHECK2(*cp, ETHER_ADDR_LEN); + ND_PRINT((ndo, ", forwarding address %s", etheraddr_string(cp))); + cp += ETHER_ADDR_LEN; + /* data */ + ND_PRINT((ndo, ", data (%u octets)", len - 8)); + ND_TCHECK2(*cp, len - 8); + break; + default: + ND_TCHECK2(*cp, len - 2); + break; + } + return; + +corrupt: + ND_PRINT((ndo, "%s", cstr)); + ND_TCHECK2(*cp, ep - cp); + return; +trunc: + ND_PRINT((ndo, "%s", tstr)); +} + +void +loopback_print(netdissect_options *ndo, const u_char *cp, const u_int len) +{ + const u_char *ep = cp + len; + uint16_t skipCount; + + ND_PRINT((ndo, "Loopback")); + if (len < 2) + goto corrupt; + /* skipCount */ + ND_TCHECK2(*cp, 2); + skipCount = EXTRACT_LE_16BITS(cp); + cp += 2; + ND_PRINT((ndo, ", skipCount %u", skipCount)); + if (skipCount % 8) + ND_PRINT((ndo, " (bogus)")); + if (skipCount > len - 2) + goto corrupt; + loopback_message_print(ndo, cp + skipCount, len - 2 - skipCount); + return; + +corrupt: + ND_PRINT((ndo, "%s", cstr)); + ND_TCHECK2(*cp, ep - cp); + return; +trunc: + ND_PRINT((ndo, "%s", tstr)); +} + diff --git a/tests/TESTLIST b/tests/TESTLIST index 61f7981b..8a1c5f78 100644 --- a/tests/TESTLIST +++ b/tests/TESTLIST @@ -170,3 +170,6 @@ syslog-v syslog_udp.pcap syslog-v.out -t -v #IPv6 tests ipv6-bad-version.pcap ipv6-bad-version.pcap ipv6-bad-version.out -t + +# Loopback/CTP test case +loopback loopback.pcap loopback.out -t diff --git a/tests/loopback.out b/tests/loopback.out new file mode 100644 index 00000000..7b8dece3 --- /dev/null +++ b/tests/loopback.out @@ -0,0 +1,6 @@ +Loopback, skipCount 0, Forward Data, forwarding address aa:00:04:00:1d:04, data (44 octets) +Loopback, skipCount 8, Reply, receipt number 1, data (40 octets) +Loopback, skipCount 0, Forward Data, forwarding address aa:00:04:00:6a:04, data (60 octets) +Loopback, skipCount 8, Forward Data, forwarding address aa:00:04:00:69:04, data (52 octets) +Loopback, skipCount 16, Forward Data, forwarding address aa:00:04:00:1d:04, data (44 octets) +Loopback, skipCount 24, Reply, receipt number 2, data (40 octets) diff --git a/tests/loopback.pcap b/tests/loopback.pcap Binary files differnew file mode 100644 index 00000000..384c0d38 --- /dev/null +++ b/tests/loopback.pcap |