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40185ca67a
tcpdump/print-ppp.c
Guy Harris f6ae2501fe CVE-2016-7933/Add some bounds checks. 
Fixes a heap overflow found with American Fuzzy Lop by Hanno Böck.
2017-01-18 09:16:35 +01:00

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/*
* Copyright (c) 1990, 1991, 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.
*
* Extensively modified by Motonori Shindo (mshindo@mshindo.net) for more
* complete PPP support.
*/
/* \summary: Point to Point Protocol (PPP) printer */
/*
* TODO:
* o resolve XXX as much as possible
* o MP support
* o BAP support
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <netdissect-stdinc.h>
#ifdef __bsdi__
#include <net/slcompress.h>
#include <net/if_ppp.h>
#endif
#include <stdlib.h>
#include "netdissect.h"
#include "extract.h"
#include "addrtoname.h"
#include "ppp.h"
#include "chdlc.h"
#include "ethertype.h"
#include "oui.h"
/*
* The following constatns are defined by IANA. Please refer to
* http://www.isi.edu/in-notes/iana/assignments/ppp-numbers
* for the up-to-date information.
*/
/* Protocol Codes defined in ppp.h */
static const struct tok ppptype2str[] = {
{ PPP_IP, "IP" },
{ PPP_OSI, "OSI" },
{ PPP_NS, "NS" },
{ PPP_DECNET, "DECNET" },
{ PPP_APPLE, "APPLE" },
{ PPP_IPX, "IPX" },
{ PPP_VJC, "VJC IP" },
{ PPP_VJNC, "VJNC IP" },
{ PPP_BRPDU, "BRPDU" },
{ PPP_STII, "STII" },
{ PPP_VINES, "VINES" },
{ PPP_MPLS_UCAST, "MPLS" },
{ PPP_MPLS_MCAST, "MPLS" },
{ PPP_COMP, "Compressed"},
{ PPP_ML, "MLPPP"},
{ PPP_IPV6, "IP6"},
{ PPP_HELLO, "HELLO" },
{ PPP_LUXCOM, "LUXCOM" },
{ PPP_SNS, "SNS" },
{ PPP_IPCP, "IPCP" },
{ PPP_OSICP, "OSICP" },
{ PPP_NSCP, "NSCP" },
{ PPP_DECNETCP, "DECNETCP" },
{ PPP_APPLECP, "APPLECP" },
{ PPP_IPXCP, "IPXCP" },
{ PPP_STIICP, "STIICP" },
{ PPP_VINESCP, "VINESCP" },
{ PPP_IPV6CP, "IP6CP" },
{ PPP_MPLSCP, "MPLSCP" },
{ PPP_LCP, "LCP" },
{ PPP_PAP, "PAP" },
{ PPP_LQM, "LQM" },
{ PPP_CHAP, "CHAP" },
{ PPP_EAP, "EAP" },
{ PPP_SPAP, "SPAP" },
{ PPP_SPAP_OLD, "Old-SPAP" },
{ PPP_BACP, "BACP" },
{ PPP_BAP, "BAP" },
{ PPP_MPCP, "MLPPP-CP" },
{ PPP_CCP, "CCP" },
{ 0, NULL }
};
/* Control Protocols (LCP/IPCP/CCP etc.) Codes defined in RFC 1661 */
#define CPCODES_VEXT 0 /* Vendor-Specific (RFC2153) */
#define CPCODES_CONF_REQ 1 /* Configure-Request */
#define CPCODES_CONF_ACK 2 /* Configure-Ack */
#define CPCODES_CONF_NAK 3 /* Configure-Nak */
#define CPCODES_CONF_REJ 4 /* Configure-Reject */
#define CPCODES_TERM_REQ 5 /* Terminate-Request */
#define CPCODES_TERM_ACK 6 /* Terminate-Ack */
#define CPCODES_CODE_REJ 7 /* Code-Reject */
#define CPCODES_PROT_REJ 8 /* Protocol-Reject (LCP only) */
#define CPCODES_ECHO_REQ 9 /* Echo-Request (LCP only) */
#define CPCODES_ECHO_RPL 10 /* Echo-Reply (LCP only) */
#define CPCODES_DISC_REQ 11 /* Discard-Request (LCP only) */
#define CPCODES_ID 12 /* Identification (LCP only) RFC1570 */
#define CPCODES_TIME_REM 13 /* Time-Remaining (LCP only) RFC1570 */
#define CPCODES_RESET_REQ 14 /* Reset-Request (CCP only) RFC1962 */
#define CPCODES_RESET_REP 15 /* Reset-Reply (CCP only) */
static const struct tok cpcodes[] = {
{CPCODES_VEXT, "Vendor-Extension"}, /* RFC2153 */
{CPCODES_CONF_REQ, "Conf-Request"},
{CPCODES_CONF_ACK, "Conf-Ack"},
{CPCODES_CONF_NAK, "Conf-Nack"},
{CPCODES_CONF_REJ, "Conf-Reject"},
{CPCODES_TERM_REQ, "Term-Request"},
{CPCODES_TERM_ACK, "Term-Ack"},
{CPCODES_CODE_REJ, "Code-Reject"},
{CPCODES_PROT_REJ, "Prot-Reject"},
{CPCODES_ECHO_REQ, "Echo-Request"},
{CPCODES_ECHO_RPL, "Echo-Reply"},
{CPCODES_DISC_REQ, "Disc-Req"},
{CPCODES_ID, "Ident"}, /* RFC1570 */
{CPCODES_TIME_REM, "Time-Rem"}, /* RFC1570 */
{CPCODES_RESET_REQ, "Reset-Req"}, /* RFC1962 */
{CPCODES_RESET_REP, "Reset-Ack"}, /* RFC1962 */
{0, NULL}
};
/* LCP Config Options */
#define LCPOPT_VEXT 0
#define LCPOPT_MRU 1
#define LCPOPT_ACCM 2
#define LCPOPT_AP 3
#define LCPOPT_QP 4
#define LCPOPT_MN 5
#define LCPOPT_DEP6 6
#define LCPOPT_PFC 7
#define LCPOPT_ACFC 8
#define LCPOPT_FCSALT 9
#define LCPOPT_SDP 10
#define LCPOPT_NUMMODE 11
#define LCPOPT_DEP12 12
#define LCPOPT_CBACK 13
#define LCPOPT_DEP14 14
#define LCPOPT_DEP15 15
#define LCPOPT_DEP16 16
#define LCPOPT_MLMRRU 17
#define LCPOPT_MLSSNHF 18
#define LCPOPT_MLED 19
#define LCPOPT_PROP 20
#define LCPOPT_DCEID 21
#define LCPOPT_MPP 22
#define LCPOPT_LD 23
#define LCPOPT_LCPAOPT 24
#define LCPOPT_COBS 25
#define LCPOPT_PE 26
#define LCPOPT_MLHF 27
#define LCPOPT_I18N 28
#define LCPOPT_SDLOS 29
#define LCPOPT_PPPMUX 30
#define LCPOPT_MIN LCPOPT_VEXT
#define LCPOPT_MAX LCPOPT_PPPMUX
static const char *lcpconfopts[] = {
"Vend-Ext", /* (0) */
"MRU", /* (1) */
"ACCM", /* (2) */
"Auth-Prot", /* (3) */
"Qual-Prot", /* (4) */
"Magic-Num", /* (5) */
"deprecated(6)", /* used to be a Quality Protocol */
"PFC", /* (7) */
"ACFC", /* (8) */
"FCS-Alt", /* (9) */
"SDP", /* (10) */
"Num-Mode", /* (11) */
"deprecated(12)", /* used to be a Multi-Link-Procedure*/
"Call-Back", /* (13) */
"deprecated(14)", /* used to be a Connect-Time */
"deprecated(15)", /* used to be a Compund-Frames */
"deprecated(16)", /* used to be a Nominal-Data-Encap */
"MRRU", /* (17) */
"12-Bit seq #", /* (18) */
"End-Disc", /* (19) */
"Proprietary", /* (20) */
"DCE-Id", /* (21) */
"MP+", /* (22) */
"Link-Disc", /* (23) */
"LCP-Auth-Opt", /* (24) */
"COBS", /* (25) */
"Prefix-elision", /* (26) */
"Multilink-header-Form",/* (27) */
"I18N", /* (28) */
"SDL-over-SONET/SDH", /* (29) */
"PPP-Muxing", /* (30) */
};
/* ECP - to be supported */
/* CCP Config Options */
#define CCPOPT_OUI 0 /* RFC1962 */
#define CCPOPT_PRED1 1 /* RFC1962 */
#define CCPOPT_PRED2 2 /* RFC1962 */
#define CCPOPT_PJUMP 3 /* RFC1962 */
/* 4-15 unassigned */
#define CCPOPT_HPPPC 16 /* RFC1962 */
#define CCPOPT_STACLZS 17 /* RFC1974 */
#define CCPOPT_MPPC 18 /* RFC2118 */
#define CCPOPT_GFZA 19 /* RFC1962 */
#define CCPOPT_V42BIS 20 /* RFC1962 */
#define CCPOPT_BSDCOMP 21 /* RFC1977 */
/* 22 unassigned */
#define CCPOPT_LZSDCP 23 /* RFC1967 */
#define CCPOPT_MVRCA 24 /* RFC1975 */
#define CCPOPT_DEC 25 /* RFC1976 */
#define CCPOPT_DEFLATE 26 /* RFC1979 */
/* 27-254 unassigned */
#define CCPOPT_RESV 255 /* RFC1962 */
static const struct tok ccpconfopts_values[] = {
{ CCPOPT_OUI, "OUI" },
{ CCPOPT_PRED1, "Pred-1" },
{ CCPOPT_PRED2, "Pred-2" },
{ CCPOPT_PJUMP, "Puddle" },
{ CCPOPT_HPPPC, "HP-PPC" },
{ CCPOPT_STACLZS, "Stac-LZS" },
{ CCPOPT_MPPC, "MPPC" },
{ CCPOPT_GFZA, "Gand-FZA" },
{ CCPOPT_V42BIS, "V.42bis" },
{ CCPOPT_BSDCOMP, "BSD-Comp" },
{ CCPOPT_LZSDCP, "LZS-DCP" },
{ CCPOPT_MVRCA, "MVRCA" },
{ CCPOPT_DEC, "DEC" },
{ CCPOPT_DEFLATE, "Deflate" },
{ CCPOPT_RESV, "Reserved"},
{0, NULL}
};
/* BACP Config Options */
#define BACPOPT_FPEER 1 /* RFC2125 */
static const struct tok bacconfopts_values[] = {
{ BACPOPT_FPEER, "Favored-Peer" },
{0, NULL}
};
/* SDCP - to be supported */
/* IPCP Config Options */
#define IPCPOPT_2ADDR 1 /* RFC1172, RFC1332 (deprecated) */
#define IPCPOPT_IPCOMP 2 /* RFC1332 */
#define IPCPOPT_ADDR 3 /* RFC1332 */
#define IPCPOPT_MOBILE4 4 /* RFC2290 */
#define IPCPOPT_PRIDNS 129 /* RFC1877 */
#define IPCPOPT_PRINBNS 130 /* RFC1877 */
#define IPCPOPT_SECDNS 131 /* RFC1877 */
#define IPCPOPT_SECNBNS 132 /* RFC1877 */
static const struct tok ipcpopt_values[] = {
{ IPCPOPT_2ADDR, "IP-Addrs" },
{ IPCPOPT_IPCOMP, "IP-Comp" },
{ IPCPOPT_ADDR, "IP-Addr" },
{ IPCPOPT_MOBILE4, "Home-Addr" },
{ IPCPOPT_PRIDNS, "Pri-DNS" },
{ IPCPOPT_PRINBNS, "Pri-NBNS" },
{ IPCPOPT_SECDNS, "Sec-DNS" },
{ IPCPOPT_SECNBNS, "Sec-NBNS" },
{ 0, NULL }
};
#define IPCPOPT_IPCOMP_HDRCOMP 0x61 /* rfc3544 */
#define IPCPOPT_IPCOMP_MINLEN 14
static const struct tok ipcpopt_compproto_values[] = {
{ PPP_VJC, "VJ-Comp" },
{ IPCPOPT_IPCOMP_HDRCOMP, "IP Header Compression" },
{ 0, NULL }
};
static const struct tok ipcpopt_compproto_subopt_values[] = {
{ 1, "RTP-Compression" },
{ 2, "Enhanced RTP-Compression" },
{ 0, NULL }
};
/* IP6CP Config Options */
#define IP6CP_IFID 1
static const struct tok ip6cpopt_values[] = {
{ IP6CP_IFID, "Interface-ID" },
{ 0, NULL }
};
/* ATCP - to be supported */
/* OSINLCP - to be supported */
/* BVCP - to be supported */
/* BCP - to be supported */
/* IPXCP - to be supported */
/* MPLSCP - to be supported */
/* Auth Algorithms */
/* 0-4 Reserved (RFC1994) */
#define AUTHALG_CHAPMD5 5 /* RFC1994 */
#define AUTHALG_MSCHAP1 128 /* RFC2433 */
#define AUTHALG_MSCHAP2 129 /* RFC2795 */
static const struct tok authalg_values[] = {
{ AUTHALG_CHAPMD5, "MD5" },
{ AUTHALG_MSCHAP1, "MS-CHAPv1" },
{ AUTHALG_MSCHAP2, "MS-CHAPv2" },
{ 0, NULL }
};
/* FCS Alternatives - to be supported */
/* Multilink Endpoint Discriminator (RFC1717) */
#define MEDCLASS_NULL 0 /* Null Class */
#define MEDCLASS_LOCAL 1 /* Locally Assigned */
#define MEDCLASS_IPV4 2 /* Internet Protocol (IPv4) */
#define MEDCLASS_MAC 3 /* IEEE 802.1 global MAC address */
#define MEDCLASS_MNB 4 /* PPP Magic Number Block */
#define MEDCLASS_PSNDN 5 /* Public Switched Network Director Number */
/* PPP LCP Callback */
#define CALLBACK_AUTH 0 /* Location determined by user auth */
#define CALLBACK_DSTR 1 /* Dialing string */
#define CALLBACK_LID 2 /* Location identifier */
#define CALLBACK_E164 3 /* E.164 number */
#define CALLBACK_X500 4 /* X.500 distinguished name */
#define CALLBACK_CBCP 6 /* Location is determined during CBCP nego */
static const struct tok ppp_callback_values[] = {
{ CALLBACK_AUTH, "UserAuth" },
{ CALLBACK_DSTR, "DialString" },
{ CALLBACK_LID, "LocalID" },
{ CALLBACK_E164, "E.164" },
{ CALLBACK_X500, "X.500" },
{ CALLBACK_CBCP, "CBCP" },
{ 0, NULL }
};
/* CHAP */
#define CHAP_CHAL 1
#define CHAP_RESP 2
#define CHAP_SUCC 3
#define CHAP_FAIL 4
static const struct tok chapcode_values[] = {
{ CHAP_CHAL, "Challenge" },
{ CHAP_RESP, "Response" },
{ CHAP_SUCC, "Success" },
{ CHAP_FAIL, "Fail" },
{ 0, NULL}
};
/* PAP */
#define PAP_AREQ 1
#define PAP_AACK 2
#define PAP_ANAK 3
static const struct tok papcode_values[] = {
{ PAP_AREQ, "Auth-Req" },
{ PAP_AACK, "Auth-ACK" },
{ PAP_ANAK, "Auth-NACK" },
{ 0, NULL }
};
/* BAP */
#define BAP_CALLREQ 1
#define BAP_CALLRES 2
#define BAP_CBREQ 3
#define BAP_CBRES 4
#define BAP_LDQREQ 5
#define BAP_LDQRES 6
#define BAP_CSIND 7
#define BAP_CSRES 8
static int print_lcp_config_options(netdissect_options *, const u_char *p, int);
static int print_ipcp_config_options(netdissect_options *, const u_char *p, int);
static int print_ip6cp_config_options(netdissect_options *, const u_char *p, int);
static int print_ccp_config_options(netdissect_options *, const u_char *p, int);
static int print_bacp_config_options(netdissect_options *, const u_char *p, int);
static void handle_ppp(netdissect_options *, u_int proto, const u_char *p, int length);
/* generic Control Protocol (e.g. LCP, IPCP, CCP, etc.) handler */
static void
handle_ctrl_proto(netdissect_options *ndo,
u_int proto, const u_char *pptr, int length)
{
const char *typestr;
u_int code, len;
int (*pfunc)(netdissect_options *, const u_char *, int);
int x, j;
const u_char *tptr;
tptr=pptr;
typestr = tok2str(ppptype2str, "unknown ctrl-proto (0x%04x)", proto);
ND_PRINT((ndo, "%s, ", typestr));
if (length < 4) /* FIXME weak boundary checking */
goto trunc;
ND_TCHECK2(*tptr, 2);
code = *tptr++;
ND_PRINT((ndo, "%s (0x%02x), id %u, length %u",
tok2str(cpcodes, "Unknown Opcode",code),
code,
*tptr++, /* ID */
length + 2));
if (!ndo->ndo_vflag)
return;
if (length <= 4)
return; /* there may be a NULL confreq etc. */
ND_TCHECK2(*tptr, 2);
len = EXTRACT_16BITS(tptr);
tptr += 2;
ND_PRINT((ndo, "\n\tencoded length %u (=Option(s) length %u)", len, len - 4));
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, pptr - 2, "\n\t", 6);
switch (code) {
case CPCODES_VEXT:
if (length < 11)
break;
ND_TCHECK2(*tptr, 4);
ND_PRINT((ndo, "\n\t Magic-Num 0x%08x", EXTRACT_32BITS(tptr)));
tptr += 4;
ND_TCHECK2(*tptr, 3);
ND_PRINT((ndo, " Vendor: %s (%u)",
tok2str(oui_values,"Unknown",EXTRACT_24BITS(tptr)),
EXTRACT_24BITS(tptr)));
/* XXX: need to decode Kind and Value(s)? */
break;
case CPCODES_CONF_REQ:
case CPCODES_CONF_ACK:
case CPCODES_CONF_NAK:
case CPCODES_CONF_REJ:
x = len - 4; /* Code(1), Identifier(1) and Length(2) */
do {
switch (proto) {
case PPP_LCP:
pfunc = print_lcp_config_options;
break;
case PPP_IPCP:
pfunc = print_ipcp_config_options;
break;
case PPP_IPV6CP:
pfunc = print_ip6cp_config_options;
break;
case PPP_CCP:
pfunc = print_ccp_config_options;
break;
case PPP_BACP:
pfunc = print_bacp_config_options;
break;
default:
/*
* No print routine for the options for
* this protocol.
*/
pfunc = NULL;
break;
}
if (pfunc == NULL) /* catch the above null pointer if unknown CP */
break;
if ((j = (*pfunc)(ndo, tptr, len)) == 0)
break;
x -= j;
tptr += j;
} while (x > 0);
break;
case CPCODES_TERM_REQ:
case CPCODES_TERM_ACK:
/* XXX: need to decode Data? */
break;
case CPCODES_CODE_REJ:
/* XXX: need to decode Rejected-Packet? */
break;
case CPCODES_PROT_REJ:
if (length < 6)
break;
ND_TCHECK2(*tptr, 2);
ND_PRINT((ndo, "\n\t Rejected %s Protocol (0x%04x)",
tok2str(ppptype2str,"unknown", EXTRACT_16BITS(tptr)),
EXTRACT_16BITS(tptr)));
/* XXX: need to decode Rejected-Information? - hexdump for now */
if (len > 6) {
ND_PRINT((ndo, "\n\t Rejected Packet"));
print_unknown_data(ndo, tptr + 2, "\n\t ", len - 2);
}
break;
case CPCODES_ECHO_REQ:
case CPCODES_ECHO_RPL:
case CPCODES_DISC_REQ:
if (length < 8)
break;
ND_TCHECK2(*tptr, 4);
ND_PRINT((ndo, "\n\t Magic-Num 0x%08x", EXTRACT_32BITS(tptr)));
/* XXX: need to decode Data? - hexdump for now */
if (len > 8) {
ND_PRINT((ndo, "\n\t -----trailing data-----"));
ND_TCHECK2(tptr[4], len - 8);
print_unknown_data(ndo, tptr + 4, "\n\t ", len - 8);
}
break;
case CPCODES_ID:
if (length < 8)
break;
ND_TCHECK2(*tptr, 4);
ND_PRINT((ndo, "\n\t Magic-Num 0x%08x", EXTRACT_32BITS(tptr)));
/* RFC 1661 says this is intended to be human readable */
if (len > 8) {
ND_PRINT((ndo, "\n\t Message\n\t "));
if (fn_printn(ndo, tptr + 4, len - 4, ndo->ndo_snapend))
goto trunc;
}
break;
case CPCODES_TIME_REM:
if (length < 12)
break;
ND_TCHECK2(*tptr, 4);
ND_PRINT((ndo, "\n\t Magic-Num 0x%08x", EXTRACT_32BITS(tptr)));
ND_TCHECK2(*(tptr + 4), 4);
ND_PRINT((ndo, ", Seconds-Remaining %us", EXTRACT_32BITS(tptr + 4)));
/* XXX: need to decode Message? */
break;
default:
/* XXX this is dirty but we do not get the
* original pointer passed to the begin
* the PPP packet */
if (ndo->ndo_vflag <= 1)
print_unknown_data(ndo, pptr - 2, "\n\t ", length + 2);
break;
}
return;
trunc:
ND_PRINT((ndo, "[|%s]", typestr));
}
/* LCP config options */
static int
print_lcp_config_options(netdissect_options *ndo,
const u_char *p, int length)
{
int len, opt;
if (length < 2)
return 0;
ND_TCHECK2(*p, 2);
len = p[1];
opt = p[0];
if (length < len)
return 0;
if (len < 2) {
if ((opt >= LCPOPT_MIN) && (opt <= LCPOPT_MAX))
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
lcpconfopts[opt], opt, len));
else
ND_PRINT((ndo, "\n\tunknown LCP option 0x%02x", opt));
return 0;
}
if ((opt >= LCPOPT_MIN) && (opt <= LCPOPT_MAX))
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u", lcpconfopts[opt], opt, len));
else {
ND_PRINT((ndo, "\n\tunknown LCP option 0x%02x", opt));
return len;
}
switch (opt) {
case LCPOPT_VEXT:
if (len < 6) {
ND_PRINT((ndo, " (length bogus, should be >= 6)"));
return len;
}
ND_TCHECK2(*(p + 2), 3);
ND_PRINT((ndo, ": Vendor: %s (%u)",
tok2str(oui_values,"Unknown",EXTRACT_24BITS(p+2)),
EXTRACT_24BITS(p + 2)));
#if 0
ND_TCHECK(p[5]);
ND_PRINT((ndo, ", kind: 0x%02x", p[5]));
ND_PRINT((ndo, ", Value: 0x"));
for (i = 0; i < len - 6; i++) {
ND_TCHECK(p[6 + i]);
ND_PRINT((ndo, "%02x", p[6 + i]));
}
#endif
break;
case LCPOPT_MRU:
if (len != 4) {
ND_PRINT((ndo, " (length bogus, should be = 4)"));
return len;
}
ND_TCHECK2(*(p + 2), 2);
ND_PRINT((ndo, ": %u", EXTRACT_16BITS(p + 2)));
break;
case LCPOPT_ACCM:
if (len != 6) {
ND_PRINT((ndo, " (length bogus, should be = 6)"));
return len;
}
ND_TCHECK2(*(p + 2), 4);
ND_PRINT((ndo, ": 0x%08x", EXTRACT_32BITS(p + 2)));
break;
case LCPOPT_AP:
if (len < 4) {
ND_PRINT((ndo, " (length bogus, should be >= 4)"));
return len;
}
ND_TCHECK2(*(p + 2), 2);
ND_PRINT((ndo, ": %s", tok2str(ppptype2str, "Unknown Auth Proto (0x04x)", EXTRACT_16BITS(p + 2))));
switch (EXTRACT_16BITS(p+2)) {
case PPP_CHAP:
ND_TCHECK(p[4]);
ND_PRINT((ndo, ", %s", tok2str(authalg_values, "Unknown Auth Alg %u", p[4])));
break;
case PPP_PAP: /* fall through */
case PPP_EAP:
case PPP_SPAP:
case PPP_SPAP_OLD:
break;
default:
print_unknown_data(ndo, p, "\n\t", len);
}
break;
case LCPOPT_QP:
if (len < 4) {
ND_PRINT((ndo, " (length bogus, should be >= 4)"));
return 0;
}
ND_TCHECK2(*(p + 2), 2);
if (EXTRACT_16BITS(p+2) == PPP_LQM)
ND_PRINT((ndo, ": LQR"));
else
ND_PRINT((ndo, ": unknown"));
break;
case LCPOPT_MN:
if (len != 6) {
ND_PRINT((ndo, " (length bogus, should be = 6)"));
return 0;
}
ND_TCHECK2(*(p + 2), 4);
ND_PRINT((ndo, ": 0x%08x", EXTRACT_32BITS(p + 2)));
break;
case LCPOPT_PFC:
break;
case LCPOPT_ACFC:
break;
case LCPOPT_LD:
if (len != 4) {
ND_PRINT((ndo, " (length bogus, should be = 4)"));
return 0;
}
ND_TCHECK2(*(p + 2), 2);
ND_PRINT((ndo, ": 0x%04x", EXTRACT_16BITS(p + 2)));
break;
case LCPOPT_CBACK:
if (len < 3) {
ND_PRINT((ndo, " (length bogus, should be >= 3)"));
return 0;
}
ND_PRINT((ndo, ": "));
ND_TCHECK(p[2]);
ND_PRINT((ndo, ": Callback Operation %s (%u)",
tok2str(ppp_callback_values, "Unknown", p[2]),
p[2]));
break;
case LCPOPT_MLMRRU:
if (len != 4) {
ND_PRINT((ndo, " (length bogus, should be = 4)"));
return 0;
}
ND_TCHECK2(*(p + 2), 2);
ND_PRINT((ndo, ": %u", EXTRACT_16BITS(p + 2)));
break;
case LCPOPT_MLED:
if (len < 3) {
ND_PRINT((ndo, " (length bogus, should be >= 3)"));
return 0;
}
ND_TCHECK(p[2]);
switch (p[2]) { /* class */
case MEDCLASS_NULL:
ND_PRINT((ndo, ": Null"));
break;
case MEDCLASS_LOCAL:
ND_PRINT((ndo, ": Local")); /* XXX */
break;
case MEDCLASS_IPV4:
if (len != 7) {
ND_PRINT((ndo, " (length bogus, should be = 7)"));
return 0;
}
ND_TCHECK2(*(p + 3), 4);
ND_PRINT((ndo, ": IPv4 %s", ipaddr_string(ndo, p + 3)));
break;
case MEDCLASS_MAC:
if (len != 9) {
ND_PRINT((ndo, " (length bogus, should be = 9)"));
return 0;
}
ND_TCHECK2(*(p + 3), 6);
ND_PRINT((ndo, ": MAC %s", etheraddr_string(ndo, p + 3)));
break;
case MEDCLASS_MNB:
ND_PRINT((ndo, ": Magic-Num-Block")); /* XXX */
break;
case MEDCLASS_PSNDN:
ND_PRINT((ndo, ": PSNDN")); /* XXX */
break;
default:
ND_PRINT((ndo, ": Unknown class %u", p[2]));
break;
}
break;
/* XXX: to be supported */
#if 0
case LCPOPT_DEP6:
case LCPOPT_FCSALT:
case LCPOPT_SDP:
case LCPOPT_NUMMODE:
case LCPOPT_DEP12:
case LCPOPT_DEP14:
case LCPOPT_DEP15:
case LCPOPT_DEP16:
case LCPOPT_MLSSNHF:
case LCPOPT_PROP:
case LCPOPT_DCEID:
case LCPOPT_MPP:
case LCPOPT_LCPAOPT:
case LCPOPT_COBS:
case LCPOPT_PE:
case LCPOPT_MLHF:
case LCPOPT_I18N:
case LCPOPT_SDLOS:
case LCPOPT_PPPMUX:
break;
#endif
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2); /* exclude TLV header */
return len;
trunc:
ND_PRINT((ndo, "[|lcp]"));
return 0;
}
/* ML-PPP*/
static const struct tok ppp_ml_flag_values[] = {
{ 0x80, "begin" },
{ 0x40, "end" },
{ 0, NULL }
};
static void
handle_mlppp(netdissect_options *ndo,
const u_char *p, int length)
{
if (!ndo->ndo_eflag)
ND_PRINT((ndo, "MLPPP, "));
ND_PRINT((ndo, "seq 0x%03x, Flags [%s], length %u",
(EXTRACT_16BITS(p))&0x0fff, /* only support 12-Bit sequence space for now */
bittok2str(ppp_ml_flag_values, "none", *p & 0xc0),
length));
}
/* CHAP */
static void
handle_chap(netdissect_options *ndo,
const u_char *p, int length)
{
u_int code, len;
int val_size, name_size, msg_size;
const u_char *p0;
int i;
p0 = p;
if (length < 1) {
ND_PRINT((ndo, "[|chap]"));
return;
} else if (length < 4) {
ND_TCHECK(*p);
ND_PRINT((ndo, "[|chap 0x%02x]", *p));
return;
}
ND_TCHECK(*p);
code = *p;
ND_PRINT((ndo, "CHAP, %s (0x%02x)",
tok2str(chapcode_values,"unknown",code),
code));
p++;
ND_TCHECK(*p);
ND_PRINT((ndo, ", id %u", *p)); /* ID */
p++;
ND_TCHECK2(*p, 2);
len = EXTRACT_16BITS(p);
p += 2;
/*
* Note that this is a generic CHAP decoding routine. Since we
* don't know which flavor of CHAP (i.e. CHAP-MD5, MS-CHAPv1,
* MS-CHAPv2) is used at this point, we can't decode packet
* specifically to each algorithms. Instead, we simply decode
* the GCD (Gratest Common Denominator) for all algorithms.
*/
switch (code) {
case CHAP_CHAL:
case CHAP_RESP:
if (length - (p - p0) < 1)
return;
ND_TCHECK(*p);
val_size = *p; /* value size */
p++;
if (length - (p - p0) < val_size)
return;
ND_PRINT((ndo, ", Value "));
for (i = 0; i < val_size; i++) {
ND_TCHECK(*p);
ND_PRINT((ndo, "%02x", *p++));
}
name_size = len - (p - p0);
ND_PRINT((ndo, ", Name "));
for (i = 0; i < name_size; i++) {
ND_TCHECK(*p);
safeputchar(ndo, *p++);
}
break;
case CHAP_SUCC:
case CHAP_FAIL:
msg_size = len - (p - p0);
ND_PRINT((ndo, ", Msg "));
for (i = 0; i< msg_size; i++) {
ND_TCHECK(*p);
safeputchar(ndo, *p++);
}
break;
}
return;
trunc:
ND_PRINT((ndo, "[|chap]"));
}
/* PAP (see RFC 1334) */
static void
handle_pap(netdissect_options *ndo,
const u_char *p, int length)
{
u_int code, len;
int peerid_len, passwd_len, msg_len;
const u_char *p0;
int i;
p0 = p;
if (length < 1) {
ND_PRINT((ndo, "[|pap]"));
return;
} else if (length < 4) {
ND_TCHECK(*p);
ND_PRINT((ndo, "[|pap 0x%02x]", *p));
return;
}
ND_TCHECK(*p);
code = *p;
ND_PRINT((ndo, "PAP, %s (0x%02x)",
tok2str(papcode_values, "unknown", code),
code));
p++;
ND_TCHECK(*p);
ND_PRINT((ndo, ", id %u", *p)); /* ID */
p++;
ND_TCHECK2(*p, 2);
len = EXTRACT_16BITS(p);
p += 2;
if ((int)len > length) {
ND_PRINT((ndo, ", length %u > packet size", len));
return;
}
length = len;
if (length < (p - p0)) {
ND_PRINT((ndo, ", length %u < PAP header length", length));
return;
}
switch (code) {
case PAP_AREQ:
/* A valid Authenticate-Request is 6 or more octets long. */
if (len < 6)
goto trunc;
if (length - (p - p0) < 1)
return;
ND_TCHECK(*p);
peerid_len = *p; /* Peer-ID Length */
p++;
if (length - (p - p0) < peerid_len)
return;
ND_PRINT((ndo, ", Peer "));
for (i = 0; i < peerid_len; i++) {
ND_TCHECK(*p);
safeputchar(ndo, *p++);
}
if (length - (p - p0) < 1)
return;
ND_TCHECK(*p);
passwd_len = *p; /* Password Length */
p++;
if (length - (p - p0) < passwd_len)
return;
ND_PRINT((ndo, ", Name "));
for (i = 0; i < passwd_len; i++) {
ND_TCHECK(*p);
safeputchar(ndo, *p++);
}
break;
case PAP_AACK:
case PAP_ANAK:
/* Although some implementations ignore truncation at
* this point and at least one generates a truncated
* packet, RFC 1334 section 2.2.2 clearly states that
* both AACK and ANAK are at least 5 bytes long.
*/
if (len < 5)
goto trunc;
if (length - (p - p0) < 1)
return;
ND_TCHECK(*p);
msg_len = *p; /* Msg-Length */
p++;
if (length - (p - p0) < msg_len)
return;
ND_PRINT((ndo, ", Msg "));
for (i = 0; i< msg_len; i++) {
ND_TCHECK(*p);
safeputchar(ndo, *p++);
}
break;
}
return;
trunc:
ND_PRINT((ndo, "[|pap]"));
}
/* BAP */
static void
handle_bap(netdissect_options *ndo _U_,
const u_char *p _U_, int length _U_)
{
/* XXX: to be supported!! */
}
/* IPCP config options */
static int
print_ipcp_config_options(netdissect_options *ndo,
const u_char *p, int length)
{
int len, opt;
u_int compproto, ipcomp_subopttotallen, ipcomp_subopt, ipcomp_suboptlen;
if (length < 2)
return 0;
ND_TCHECK2(*p, 2);
len = p[1];
opt = p[0];
if (length < len)
return 0;
if (len < 2) {
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
tok2str(ipcpopt_values,"unknown",opt),
opt,
len));
return 0;
}
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u",
tok2str(ipcpopt_values,"unknown",opt),
opt,
len));
switch (opt) {
case IPCPOPT_2ADDR: /* deprecated */
if (len != 10) {
ND_PRINT((ndo, " (length bogus, should be = 10)"));
return len;
}
ND_TCHECK2(*(p + 6), 4);
ND_PRINT((ndo, ": src %s, dst %s",
ipaddr_string(ndo, p + 2),
ipaddr_string(ndo, p + 6)));
break;
case IPCPOPT_IPCOMP:
if (len < 4) {
ND_PRINT((ndo, " (length bogus, should be >= 4)"));
return 0;
}
ND_TCHECK2(*(p + 2), 2);
compproto = EXTRACT_16BITS(p+2);
ND_PRINT((ndo, ": %s (0x%02x):",
tok2str(ipcpopt_compproto_values, "Unknown", compproto),
compproto));
switch (compproto) {
case PPP_VJC:
/* XXX: VJ-Comp parameters should be decoded */
break;
case IPCPOPT_IPCOMP_HDRCOMP:
if (len < IPCPOPT_IPCOMP_MINLEN) {
ND_PRINT((ndo, " (length bogus, should be >= %u)",
IPCPOPT_IPCOMP_MINLEN));
return 0;
}
ND_TCHECK2(*(p + 2), IPCPOPT_IPCOMP_MINLEN);
ND_PRINT((ndo, "\n\t TCP Space %u, non-TCP Space %u" \
", maxPeriod %u, maxTime %u, maxHdr %u",
EXTRACT_16BITS(p+4),
EXTRACT_16BITS(p+6),
EXTRACT_16BITS(p+8),
EXTRACT_16BITS(p+10),
EXTRACT_16BITS(p+12)));
/* suboptions present ? */
if (len > IPCPOPT_IPCOMP_MINLEN) {
ipcomp_subopttotallen = len - IPCPOPT_IPCOMP_MINLEN;
p += IPCPOPT_IPCOMP_MINLEN;
ND_PRINT((ndo, "\n\t Suboptions, length %u", ipcomp_subopttotallen));
while (ipcomp_subopttotallen >= 2) {
ND_TCHECK2(*p, 2);
ipcomp_subopt = *p;
ipcomp_suboptlen = *(p+1);
/* sanity check */
if (ipcomp_subopt == 0 ||
ipcomp_suboptlen == 0 )
break;
/* XXX: just display the suboptions for now */
ND_PRINT((ndo, "\n\t\t%s Suboption #%u, length %u",
tok2str(ipcpopt_compproto_subopt_values,
"Unknown",
ipcomp_subopt),
ipcomp_subopt,
ipcomp_suboptlen));
ipcomp_subopttotallen -= ipcomp_suboptlen;
p += ipcomp_suboptlen;
}
}
break;
default:
break;
}
break;
case IPCPOPT_ADDR: /* those options share the same format - fall through */
case IPCPOPT_MOBILE4:
case IPCPOPT_PRIDNS:
case IPCPOPT_PRINBNS:
case IPCPOPT_SECDNS:
case IPCPOPT_SECNBNS:
if (len != 6) {
ND_PRINT((ndo, " (length bogus, should be = 6)"));
return 0;
}
ND_TCHECK2(*(p + 2), 4);
ND_PRINT((ndo, ": %s", ipaddr_string(ndo, p + 2)));
break;
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2); /* exclude TLV header */
return len;
trunc:
ND_PRINT((ndo, "[|ipcp]"));
return 0;
}
/* IP6CP config options */
static int
print_ip6cp_config_options(netdissect_options *ndo,
const u_char *p, int length)
{
int len, opt;
if (length < 2)
return 0;
ND_TCHECK2(*p, 2);
len = p[1];
opt = p[0];
if (length < len)
return 0;
if (len < 2) {
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
tok2str(ip6cpopt_values,"unknown",opt),
opt,
len));
return 0;
}
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u",
tok2str(ip6cpopt_values,"unknown",opt),
opt,
len));
switch (opt) {
case IP6CP_IFID:
if (len != 10) {
ND_PRINT((ndo, " (length bogus, should be = 10)"));
return len;
}
ND_TCHECK2(*(p + 2), 8);
ND_PRINT((ndo, ": %04x:%04x:%04x:%04x",
EXTRACT_16BITS(p + 2),
EXTRACT_16BITS(p + 4),
EXTRACT_16BITS(p + 6),
EXTRACT_16BITS(p + 8)));
break;
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2); /* exclude TLV header */
return len;
trunc:
ND_PRINT((ndo, "[|ip6cp]"));
return 0;
}
/* CCP config options */
static int
print_ccp_config_options(netdissect_options *ndo,
const u_char *p, int length)
{
int len, opt;
if (length < 2)
return 0;
ND_TCHECK2(*p, 2);
len = p[1];
opt = p[0];
if (length < len)
return 0;
if (len < 2) {
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
tok2str(ccpconfopts_values, "Unknown", opt),
opt,
len));
return 0;
}
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u",
tok2str(ccpconfopts_values, "Unknown", opt),
opt,
len));
switch (opt) {
case CCPOPT_BSDCOMP:
if (len < 3) {
ND_PRINT((ndo, " (length bogus, should be >= 3)"));
return len;
}
ND_TCHECK2(*(p + 2), 1);
ND_PRINT((ndo, ": Version: %u, Dictionary Bits: %u",
p[2] >> 5, p[2] & 0x1f));
break;
case CCPOPT_MVRCA:
if (len < 4) {
ND_PRINT((ndo, " (length bogus, should be >= 4)"));
return len;
}
ND_TCHECK2(*(p + 2), 1);
ND_PRINT((ndo, ": Features: %u, PxP: %s, History: %u, #CTX-ID: %u",
(p[2] & 0xc0) >> 6,
(p[2] & 0x20) ? "Enabled" : "Disabled",
p[2] & 0x1f, p[3]));
break;
case CCPOPT_DEFLATE:
if (len < 4) {
ND_PRINT((ndo, " (length bogus, should be >= 4)"));
return len;
}
ND_TCHECK2(*(p + 2), 1);
ND_PRINT((ndo, ": Window: %uK, Method: %s (0x%x), MBZ: %u, CHK: %u",
(p[2] & 0xf0) >> 4,
((p[2] & 0x0f) == 8) ? "zlib" : "unkown",
p[2] & 0x0f, (p[3] & 0xfc) >> 2, p[3] & 0x03));
break;
/* XXX: to be supported */
#if 0
case CCPOPT_OUI:
case CCPOPT_PRED1:
case CCPOPT_PRED2:
case CCPOPT_PJUMP:
case CCPOPT_HPPPC:
case CCPOPT_STACLZS:
case CCPOPT_MPPC:
case CCPOPT_GFZA:
case CCPOPT_V42BIS:
case CCPOPT_LZSDCP:
case CCPOPT_DEC:
case CCPOPT_RESV:
break;
#endif
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2); /* exclude TLV header */
return len;
trunc:
ND_PRINT((ndo, "[|ccp]"));
return 0;
}
/* BACP config options */
static int
print_bacp_config_options(netdissect_options *ndo,
const u_char *p, int length)
{
int len, opt;
if (length < 2)
return 0;
ND_TCHECK2(*p, 2);
len = p[1];
opt = p[0];
if (length < len)
return 0;
if (len < 2) {
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
tok2str(bacconfopts_values, "Unknown", opt),
opt,
len));
return 0;
}
ND_PRINT((ndo, "\n\t %s Option (0x%02x), length %u",
tok2str(bacconfopts_values, "Unknown", opt),
opt,
len));
switch (opt) {
case BACPOPT_FPEER:
if (len != 6) {
ND_PRINT((ndo, " (length bogus, should be = 6)"));
return len;
}
ND_TCHECK2(*(p + 2), 4);
ND_PRINT((ndo, ": Magic-Num 0x%08x", EXTRACT_32BITS(p + 2)));
break;
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, &p[2], "\n\t ", len - 2); /* exclude TLV header */
return len;
trunc:
ND_PRINT((ndo, "[|bacp]"));
return 0;
}
static void
ppp_hdlc(netdissect_options *ndo,
const u_char *p, int length)
{
u_char *b, *t, c;
const u_char *s;
int i, proto;
const void *se;
if (length <= 0)
return;
b = (u_char *)malloc(length);
if (b == NULL)
return;
/*
* Unescape all the data into a temporary, private, buffer.
* Do this so that we dont overwrite the original packet
* contents.
*/
for (s = p, t = b, i = length; i > 0 && ND_TTEST(*s); i--) {
c = *s++;
if (c == 0x7d) {
if (i <= 1 || !ND_TTEST(*s))
break;
i--;
c = *s++ ^ 0x20;
}
*t++ = c;
}
se = ndo->ndo_snapend;
ndo->ndo_snapend = t;
length = t - b;
/* now lets guess about the payload codepoint format */
if (length < 1)
goto trunc;
proto = *b; /* start with a one-octet codepoint guess */
switch (proto) {
case PPP_IP:
ip_print(ndo, b + 1, length - 1);
goto cleanup;
case PPP_IPV6:
ip6_print(ndo, b + 1, length - 1);
goto cleanup;
default: /* no luck - try next guess */
break;
}
if (length < 2)
goto trunc;
proto = EXTRACT_16BITS(b); /* next guess - load two octets */
switch (proto) {
case (PPP_ADDRESS << 8 | PPP_CONTROL): /* looks like a PPP frame */
if (length < 4)
goto trunc;
proto = EXTRACT_16BITS(b+2); /* load the PPP proto-id */
handle_ppp(ndo, proto, b + 4, length - 4);
break;
default: /* last guess - proto must be a PPP proto-id */
handle_ppp(ndo, proto, b + 2, length - 2);
break;
}
cleanup:
ndo->ndo_snapend = se;
free(b);
return;
trunc:
ndo->ndo_snapend = se;
free(b);
ND_PRINT((ndo, "[|ppp]"));
}
/* PPP */
static void
handle_ppp(netdissect_options *ndo,
u_int proto, const u_char *p, int length)
{
if ((proto & 0xff00) == 0x7e00) { /* is this an escape code ? */
ppp_hdlc(ndo, p - 1, length);
return;
}
switch (proto) {
case PPP_LCP: /* fall through */
case PPP_IPCP:
case PPP_OSICP:
case PPP_MPLSCP:
case PPP_IPV6CP:
case PPP_CCP:
case PPP_BACP:
handle_ctrl_proto(ndo, proto, p, length);
break;
case PPP_ML:
handle_mlppp(ndo, p, length);
break;
case PPP_CHAP:
handle_chap(ndo, p, length);
break;
case PPP_PAP:
handle_pap(ndo, p, length);
break;
case PPP_BAP: /* XXX: not yet completed */
handle_bap(ndo, p, length);
break;
case ETHERTYPE_IP: /*XXX*/
case PPP_VJNC:
case PPP_IP:
ip_print(ndo, p, length);
break;
case ETHERTYPE_IPV6: /*XXX*/
case PPP_IPV6:
ip6_print(ndo, p, length);
break;
case ETHERTYPE_IPX: /*XXX*/
case PPP_IPX:
ipx_print(ndo, p, length);
break;
case PPP_OSI:
isoclns_print(ndo, p, length, length);
break;
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
mpls_print(ndo, p, length);
break;
case PPP_COMP:
ND_PRINT((ndo, "compressed PPP data"));
break;
default:
ND_PRINT((ndo, "%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto)));
print_unknown_data(ndo, p, "\n\t", length);
break;
}
}
/* Standard PPP printer */
u_int
ppp_print(netdissect_options *ndo,
register const u_char *p, u_int length)
{
u_int proto,ppp_header;
u_int olen = length; /* _o_riginal length */
u_int hdr_len = 0;
/*
* Here, we assume that p points to the Address and Control
* field (if they present).
*/
if (length < 2)
goto trunc;
ND_TCHECK2(*p, 2);
ppp_header = EXTRACT_16BITS(p);
switch(ppp_header) {
case (PPP_WITHDIRECTION_IN << 8 | PPP_CONTROL):
if (ndo->ndo_eflag) ND_PRINT((ndo, "In "));
p += 2;
length -= 2;
hdr_len += 2;
break;
case (PPP_WITHDIRECTION_OUT << 8 | PPP_CONTROL):
if (ndo->ndo_eflag) ND_PRINT((ndo, "Out "));
p += 2;
length -= 2;
hdr_len += 2;
break;
case (PPP_ADDRESS << 8 | PPP_CONTROL):
p += 2; /* ACFC not used */
length -= 2;
hdr_len += 2;
break;
default:
break;
}
if (length < 2)
goto trunc;
ND_TCHECK(*p);
if (*p % 2) {
proto = *p; /* PFC is used */
p++;
length--;
hdr_len++;
} else {
ND_TCHECK2(*p, 2);
proto = EXTRACT_16BITS(p);
p += 2;
length -= 2;
hdr_len += 2;
}
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%s (0x%04x), length %u: ",
tok2str(ppptype2str, "unknown", proto),
proto,
olen));
handle_ppp(ndo, proto, p, length);
return (hdr_len);
trunc:
ND_PRINT((ndo, "[|ppp]"));
return (0);
}
/* PPP I/F printer */
u_int
ppp_if_print(netdissect_options *ndo,
const struct pcap_pkthdr *h, register const u_char *p)
{
register u_int length = h->len;
register u_int caplen = h->caplen;
if (caplen < PPP_HDRLEN) {
ND_PRINT((ndo, "[|ppp]"));
return (caplen);
}
#if 0
/*
* XXX: seems to assume that there are 2 octets prepended to an
* actual PPP frame. The 1st octet looks like Input/Output flag
* while 2nd octet is unknown, at least to me
* (mshindo@mshindo.net).
*
* That was what the original tcpdump code did.
*
* FreeBSD's "if_ppp.c" *does* set the first octet to 1 for outbound
* packets and 0 for inbound packets - but only if the
* protocol field has the 0x8000 bit set (i.e., it's a network
* control protocol); it does so before running the packet through
* "bpf_filter" to see if it should be discarded, and to see
* if we should update the time we sent the most recent packet...
*
* ...but it puts the original address field back after doing
* so.
*
* NetBSD's "if_ppp.c" doesn't set the first octet in that fashion.
*
* I don't know if any PPP implementation handed up to a BPF
* device packets with the first octet being 1 for outbound and
* 0 for inbound packets, so I (guy@alum.mit.edu) don't know
* whether that ever needs to be checked or not.
*
* Note that NetBSD has a DLT_PPP_SERIAL, which it uses for PPP,
* and its tcpdump appears to assume that the frame always
* begins with an address field and a control field, and that
* the address field might be 0x0f or 0x8f, for Cisco
* point-to-point with HDLC framing as per section 4.3.1 of RFC
* 1547, as well as 0xff, for PPP in HDLC-like framing as per
* RFC 1662.
*
* (Is the Cisco framing in question what DLT_C_HDLC, in
* BSD/OS, is?)
*/
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%c %4d %02x ", p[0] ? 'O' : 'I', length, p[1]));
#endif
ppp_print(ndo, p, length);
return (0);
}
/*
* PPP I/F printer to use if we know that RFC 1662-style PPP in HDLC-like
* framing, or Cisco PPP with HDLC framing as per section 4.3.1 of RFC 1547,
* is being used (i.e., we don't check for PPP_ADDRESS and PPP_CONTROL,
* discard them *if* those are the first two octets, and parse the remaining
* packet as a PPP packet, as "ppp_print()" does).
*
* This handles, for example, DLT_PPP_SERIAL in NetBSD.
*/
u_int
ppp_hdlc_if_print(netdissect_options *ndo,
const struct pcap_pkthdr *h, register const u_char *p)
{
register u_int length = h->len;
register u_int caplen = h->caplen;
u_int proto;
u_int hdrlen = 0;
if (caplen < 2) {
ND_PRINT((ndo, "[|ppp]"));
return (caplen);
}
switch (p[0]) {
case PPP_ADDRESS:
if (caplen < 4) {
ND_PRINT((ndo, "[|ppp]"));
return (caplen);
}
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%02x %02x %d ", p[0], p[1], length));
p += 2;
length -= 2;
hdrlen += 2;
proto = EXTRACT_16BITS(p);
p += 2;
length -= 2;
hdrlen += 2;
ND_PRINT((ndo, "%s: ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto)));
handle_ppp(ndo, proto, p, length);
break;
case CHDLC_UNICAST:
case CHDLC_BCAST:
return (chdlc_if_print(ndo, h, p));
default:
if (caplen < 4) {
ND_PRINT((ndo, "[|ppp]"));
return (caplen);
}
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%02x %02x %d ", p[0], p[1], length));
p += 2;
hdrlen += 2;
/*
* XXX - NetBSD's "ppp_netbsd_serial_if_print()" treats
* the next two octets as an Ethernet type; does that
* ever happen?
*/
ND_PRINT((ndo, "unknown addr %02x; ctrl %02x", p[0], p[1]));
break;
}
return (hdrlen);
}
#define PPP_BSDI_HDRLEN 24
/* BSD/OS specific PPP printer */
u_int
ppp_bsdos_if_print(netdissect_options *ndo _U_,
const struct pcap_pkthdr *h _U_, register const u_char *p _U_)
{
register int hdrlength;
#ifdef __bsdi__
register u_int length = h->len;
register u_int caplen = h->caplen;
uint16_t ptype;
const u_char *q;
int i;
if (caplen < PPP_BSDI_HDRLEN) {
ND_PRINT((ndo, "[|ppp]"));
return (caplen)
}
hdrlength = 0;
#if 0
if (p[0] == PPP_ADDRESS && p[1] == PPP_CONTROL) {
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%02x %02x ", p[0], p[1]));
p += 2;
hdrlength = 2;
}
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%d ", length));
/* Retrieve the protocol type */
if (*p & 01) {
/* Compressed protocol field */
ptype = *p;
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%02x ", ptype));
p++;
hdrlength += 1;
} else {
/* Un-compressed protocol field */
ptype = EXTRACT_16BITS(p);
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%04x ", ptype));
p += 2;
hdrlength += 2;
}
#else
ptype = 0; /*XXX*/
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%c ", p[SLC_DIR] ? 'O' : 'I'));
if (p[SLC_LLHL]) {
/* link level header */
struct ppp_header *ph;
q = p + SLC_BPFHDRLEN;
ph = (struct ppp_header *)q;
if (ph->phdr_addr == PPP_ADDRESS
&& ph->phdr_ctl == PPP_CONTROL) {
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%02x %02x ", q[0], q[1]));
ptype = EXTRACT_16BITS(&ph->phdr_type);
if (ndo->ndo_eflag && (ptype == PPP_VJC || ptype == PPP_VJNC)) {
ND_PRINT((ndo, "%s ", tok2str(ppptype2str,
"proto-#%d", ptype)));
}
} else {
if (ndo->ndo_eflag) {
ND_PRINT((ndo, "LLH=["));
for (i = 0; i < p[SLC_LLHL]; i++)
ND_PRINT((ndo, "%02x", q[i]));
ND_PRINT((ndo, "] "));
}
}
}
if (ndo->ndo_eflag)
ND_PRINT((ndo, "%d ", length));
if (p[SLC_CHL]) {
q = p + SLC_BPFHDRLEN + p[SLC_LLHL];
switch (ptype) {
case PPP_VJC:
ptype = vjc_print(ndo, q, ptype);
hdrlength = PPP_BSDI_HDRLEN;
p += hdrlength;
switch (ptype) {
case PPP_IP:
ip_print(ndo, p, length);
break;
case PPP_IPV6:
ip6_print(ndo, p, length);
break;
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
mpls_print(ndo, p, length);
break;
}
goto printx;
case PPP_VJNC:
ptype = vjc_print(ndo, q, ptype);
hdrlength = PPP_BSDI_HDRLEN;
p += hdrlength;
switch (ptype) {
case PPP_IP:
ip_print(ndo, p, length);
break;
case PPP_IPV6:
ip6_print(ndo, p, length);
break;
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
mpls_print(ndo, p, length);
break;
}
goto printx;
default:
if (ndo->ndo_eflag) {
ND_PRINT((ndo, "CH=["));
for (i = 0; i < p[SLC_LLHL]; i++)
ND_PRINT((ndo, "%02x", q[i]));
ND_PRINT((ndo, "] "));
}
break;
}
}
hdrlength = PPP_BSDI_HDRLEN;
#endif
length -= hdrlength;
p += hdrlength;
switch (ptype) {
case PPP_IP:
ip_print(p, length);
break;
case PPP_IPV6:
ip6_print(ndo, p, length);
break;
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
mpls_print(ndo, p, length);
break;
default:
ND_PRINT((ndo, "%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", ptype)));
}
printx:
#else /* __bsdi */
hdrlength = 0;
#endif /* __bsdi__ */
return (hdrlength);
}
/*
* Local Variables:
* c-style: whitesmith
* c-basic-offset: 8
* End:
*/
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