xref: /freebsd-11.0-release/contrib/tcpdump/print-ppp.c

/*
 * 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.
 *
 * $FreeBSD: head/contrib/tcpdump/print-ppp.c 53146 1999-11-14 11:28:11Z brian $
 */

#ifndef lint
static const char rcsid[] =
    "@(#) $Header: print-ppp.c,v 1.26 97/06/12 14:21:29 leres Exp $ (LBL)";
#endif

#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <sys/ioctl.h>

#if __STDC__
struct mbuf;
struct rtentry;
#endif
#include <net/if.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>

#include <ctype.h>
#include <netdb.h>
#include <pcap.h>
#include <stdio.h>

#include <net/ethernet.h>
#include "ethertype.h"

#include <net/ppp_defs.h>
#include "interface.h"
#include "addrtoname.h"
#include "ppp.h"

struct protonames {
	u_short protocol;
	char *name;
};

static struct protonames protonames[] = {
	/*
	 * Protocol field values.
	 */
	PPP_IP,		"IP",		/* Internet Protocol */
	PPP_XNS,	"XNS",		/* Xerox NS */
	PPP_IPX,	"IPX",		/* IPX Datagram (RFC1552) */
	PPP_VJC_COMP,	"VJC_UNCOMP",	/* VJ compressed TCP */
	PPP_VJC_UNCOMP,	"VJC_UNCOMP",	/* VJ uncompressed TCP */
	PPP_COMP,	"COMP",		/* compressed packet */
	PPP_IPCP,	"IPCP",		/* IP Control Protocol */
	PPP_IPXCP,	"IPXCP",	/* IPX Control Protocol (RFC1552) */
	PPP_CCP,	"CCP",		/* Compression Control Protocol */
	PPP_LCP,	"LCP",		/* Link Control Protocol */
	PPP_PAP,	"PAP",		/* Password Authentication Protocol */
	PPP_LQR,	"LQR",		/* Link Quality Report protocol */
	PPP_CHAP,	"CHAP",		/* Cryptographic Handshake Auth. Proto*/
};

/* LCP */

#define LCP_CONF_REQ	1
#define LCP_CONF_ACK	2
#define LCP_CONF_NAK	3
#define LCP_CONF_REJ	4
#define LCP_TERM_REQ	5
#define LCP_TERM_ACK	6
#define LCP_CODE_REJ	7
#define LCP_PROT_REJ	8
#define LCP_ECHO_REQ	9
#define LCP_ECHO_RPL	10
#define LCP_DISC_REQ	11

#define LCP_MIN	LCP_CONF_REQ
#define LCP_MAX LCP_DISC_REQ

static char *lcpcodes[] = {
	/*
	 * LCP code values (RFC1661, pp26)
	 */
	"Configure-Request",
	"Configure-Ack",
	"Configure-Nak",
	"Configure-Reject",
	"Terminate-Request",
	"Terminate-Ack",
 	"Code-Reject",
	"Protocol-Reject",
	"Echo-Request",
	"Echo-Reply",
	"Discard-Request",
};

#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_PFC	7
#define LCPOPT_ACFC	8

#define LCPOPT_MIN 0
#define LCPOPT_MAX 24

static char *lcpconfopts[] = {
	"Vendor-Ext",
	"Max-Rx-Unit",
	"Async-Ctrl-Char-Map",
	"Auth-Prot",
	"Quality-Prot",
	"Magic-Number",
	"unassigned (6)",
	"Prot-Field-Compr",
	"Add-Ctrl-Field-Compr",
	"FCS-Alternatives",
	"Self-Describing-Pad",
	"Numbered-Mode",
	"Multi-Link-Procedure",
	"Call-Back",
	"Connect-Time",
	"Compund-Frames",
	"Nominal-Data-Encap",
	"Multilink-MRRU",
	"Multilink-SSNHF",
	"Multilink-ED",
	"Proprietary",
	"DCE-Identifier",
	"Multilink-Plus-Proc",
	"Link-Discriminator",
	"LCP-Auth-Option",
};

/* CHAP */

#define CHAP_CHAL	1
#define CHAP_RESP	2
#define CHAP_SUCC	3
#define CHAP_FAIL	4

#define CHAP_CODEMIN 1
#define CHAP_CODEMAX 4

static char *chapcode[] = {
	"Challenge",
	"Response",
	"Success",
	"Failure",
};

/* PAP */

#define PAP_AREQ	1
#define PAP_AACK	2
#define PAP_ANAK	3

#define PAP_CODEMIN	1
#define PAP_CODEMAX	3

static char *papcode[] = {
	"Authenticate-Request",
	"Authenticate-Ack",
	"Authenticate-Nak",
};

/* IPCP */

#define IPCP_2ADDR	1
#define IPCP_CP		2
#define IPCP_ADDR	3

/* PPPoE */

struct typenames {
	u_short type;
	char *name;
};

static struct typenames typenames[] = {
	/*
	 * PPPoE type field values
	 */
	0x00,	"DATA",			/* PPPoE Data packet                */
	0x09,	"PADI",			/* Active Discovery Initiation      */
	0x07,	"PADO",			/* Active Discovery Offer           */
	0x19,	"PADR",			/* Active Discovery Request         */
	0x65,	"PADS",			/* Active Discovery Session-Confirm */
	0xa7,	"PADT",			/* Active Discovery Terminate       */
};

struct tagnames {
	u_short tag;
	char *name;
	int isascii;
};

static struct tagnames tagnames[] = {
  /*
   * PPPoE tag field values
   */
  0x0000, "End-Of-List",	0,	/* Optional last tag (len 0) */
  0x0101, "Service-Name",	1,	/* The (ascii) service */
  0x0102, "AC-Name",		-1,	/* Access Concentrator */
  0x0103, "Host-Uniq",		0,	/* Associate PAD[OS] with PAD[IR] */
  0x0104, "AC-Cookie",		0,	/* Optional at PADO time */
  0x0105, "Vendor-Specific",	0,	/* First 4 bytes special (ignore) */
  0x0110, "Relay-Session-Id",	0,	/* Max 12 octets, added by gateway */
  0x0201, "Service-Name-Error",	-1,	/* Request not honoured */
  0x0203, "Generic-Error",	1	/* Access Concentrator error */
};

static int handle_lcp(const u_char *p, int length);
static int print_lcp_config_options(u_char *p);
static int handle_chap(const u_char *p, int length);
static int handle_ipcp(const u_char *p, int length);
static int handle_pap(const u_char *p, int length);
static void do_ppp_print(const u_char *p, u_int length, u_int caplen);

/* Standard PPP printer */
void
ppp_hdlc_print(const u_char *p, int length)
{
	int proto = PPP_PROTOCOL(p);
	int i, j, x;
	u_char *ptr;

	printf("ID-%03d ", *(p+5));

	for (i = (sizeof(protonames) / sizeof(protonames[0])) - 1; i >= 0; --i)
	{
		if (proto == protonames[i].protocol)
		{
			printf("%s: ", protonames[i].name);

			switch(proto)
			{
				case PPP_LCP:
					handle_lcp(p, length);
					break;
				case PPP_CHAP:
					handle_chap(p, length);
					break;
				case PPP_PAP:
					handle_pap(p, length);
					break;
				case PPP_IPCP:
					handle_ipcp(p, length);
					break;
			}
			break;
		}
	}
	if (i < 0)
	{
		printf("%04x: ", proto);
	}
}

/* print LCP frame */

static int
handle_lcp(const u_char *p, int length)
{
	int x, j;
	u_char *ptr;

	x = *(p+4);

	if((x >= LCP_MIN) && (x <= LCP_MAX))
	{
		printf("%s", lcpcodes[x-1]);
	}
	else
	{
		printf("0x%02x", x);
		return;
	}

	length -= 4;

	switch(x)
	{
		case LCP_CONF_REQ:
		case LCP_CONF_ACK:
		case LCP_CONF_NAK:
		case LCP_CONF_REJ:
			x = length;
			ptr = (u_char *)p+8;
			do
			{
				if((j = print_lcp_config_options(ptr)) == 0)
					break;
				x -= j;
				ptr += j;
			}
			while(x > 0);
			break;

		case LCP_ECHO_REQ:
		case LCP_ECHO_RPL:
			printf(", Magic-Number=%d", ((*(p+8) << 24) + (*(p+9) << 16) + (*(p+10) << 8) + (*(p+11))));
			break;
		case LCP_TERM_REQ:
		case LCP_TERM_ACK:
		case LCP_CODE_REJ:
		case LCP_PROT_REJ:
		case LCP_DISC_REQ:
		default:
			break;
	}
}

/* LCP config options */

static int
print_lcp_config_options(u_char *p)
{
	int len	= *(p+1);
	int opt = *p;

	if((opt >= LCPOPT_MIN) && (opt <= LCPOPT_MAX))
		printf(", %s", lcpconfopts[opt]);

	switch(opt)
	{
		case LCPOPT_MRU:
			if(len == 4)
				printf("=%d", (*(p+2) << 8) + *(p+3));
			break;
		case LCPOPT_AP:
			if(len >= 4)
			{
				if(*(p+2) == 0xc0 && *(p+3) == 0x23)
				{
					printf(" PAP");
				}
				else if(*(p+2) == 0xc2 && *(p+3) == 0x23)
				{
					printf(" CHAP/");
					switch(*(p+4))
					{
						default:
							printf("unknown-algorithm-%d", *(p+4));
							break;
						case 5:
							printf("MD5");
							break;
						case 0x80:
							printf("Microsoft");
							break;
					}
				}
				else if(*(p+2) == 0xc2 && *(p+3) == 0x27)
				{
					printf(" EAP");
				}
				else if(*(p+2) == 0xc0 && *(p+3) == 0x27)
				{
					printf(" SPAP");
				}
				else if(*(p+2) == 0xc1 && *(p+3) == 0x23)
				{
					printf(" Old-SPAP");
				}
				else
				{
					printf("unknown");
				}
			}
			break;
		case LCPOPT_QP:
			if(len >= 4)
			{
				if(*(p+2) == 0xc0 && *(p+3) == 0x25)
					printf(" LQR");
				else
					printf(" unknown");
			}
			break;
		case LCPOPT_MN:
			if(len == 6)
			{
				printf("=%d", ((*(p+2) << 24) + (*(p+3) << 16) + (*(p+4) << 8) + (*(p+5))));
			}
			break;
		case LCPOPT_PFC:
			printf(" PFC");
			break;
		case LCPOPT_ACFC:
			printf(" ACFC");
			break;
	}
	return(len);
}

/* CHAP */

static int
handle_chap(const u_char *p, int length)
{
	int x, j;
	u_char *ptr;

	x = *(p+4);

	if((x >= CHAP_CODEMIN) && (x <= CHAP_CODEMAX))
	{
		printf("%s", chapcode[x-1]);
	}
	else
	{
		printf("0x%02x", x);
		return;
	}

	length -= 4;

	switch(x)
	{
		case CHAP_CHAL:
		case CHAP_RESP:
			printf(", Value=");
			x = *(p+8);	/* value size */
			ptr = (u_char *)p+9;
			while(--x >= 0)
				printf("%02x", *ptr++);
			x = length - *(p+8) - 1;
			printf(", Name=");
			while(--x >= 0)
				printf("%c", *ptr++);
			break;
	}
}

/* PAP */

static int
handle_pap(const u_char *p, int length)
{
	int x, j;
	u_char *ptr;

	x = *(p+4);

	if((x >= PAP_CODEMIN) && (x <= PAP_CODEMAX))
	{
		printf("%s", papcode[x-1]);
	}
	else
	{
		printf("0x%02x", x);
		return;
	}

	length -= 4;

	switch(x)
	{
		case PAP_AREQ:
			printf(", Peer-Id=");
			x = *(p+8);	/* peerid size */
			ptr = (u_char *)p+9;
			while(--x >= 0)
				printf("%c", *ptr++);
			x = *ptr++;
			printf(", Passwd=");
			while(--x >= 0)
				printf("%c", *ptr++);
			break;
		case PAP_AACK:
		case PAP_ANAK:
			break;
	}
}

/* IPCP */

static int
handle_ipcp(const u_char *p, int length)
{
	int x, j;

	x = *(p+8);

	length -= 4;

	switch(x)
	{
		case IPCP_2ADDR:
			printf("IP-Addresses");
			printf(", Src=%d.%d.%d.%d", *(p+10), *(p+11), *(p+12), *(p+13));
			printf(", Dst=%d.%d.%d.%d", *(p+14), *(p+15), *(p+16), *(p+17));
			break;

		case IPCP_CP:
			printf("IP-Compression-Protocol");
			break;

		case IPCP_ADDR:
			printf("IP-Address=%d.%d.%d.%d", *(p+10), *(p+11), *(p+12), *(p+13));
			break;
	}
}

void
ppp_if_print(u_char *user, const struct pcap_pkthdr *h,
	     register const u_char *p)
{
	register u_int length = h->len;
	register u_int caplen = h->caplen;

	ts_print(&h->ts);

	if (caplen < PPP_HDRLEN) {
		puts("[|ppp]");
		return;
	}

	/*
	 * Some printers want to get back at the link level addresses,
	 * and/or check that they're not walking off the end of the packet.
	 * Rather than pass them all the way down, we set these globals.
	 */
	packetp = p;
	snapend = p + caplen;

	do_ppp_print(p, length, caplen);
}

/*
 * Print PPPoE discovery & session packets
 */
void
pppoe_print(const u_char *p, u_int length)
{
	u_short tag, len, tlen;
	u_char type;
	int f, asc;

	fputs("PPPoE ", stdout);

	/*
	 * A PPPoE header:
	 *
	 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * |  VER  | TYPE  |      CODE     |          SESSION_ID           |
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * |            LENGTH             |           payload             ~
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 */

	type = p[1];
	for (f = sizeof typenames / sizeof typenames[0] - 1; f >= 0; f--)
		if (typenames[f].type == type) {
			fputs(typenames[f].name, stdout);
			break;
		}

	if (f == -1) {
		printf("<0x%02x>\n", type);
	}

	len = ntohs(*(u_short *)(p + 4));
	printf(" v%d, type %d, sess %d len %d", p[0] >> 4, p[0] & 0xf,
	    ntohs(*(u_short *)(p + 2)), len);

	if (type == 0x00) {
		p += 4;
		length -= 4;
		if (len > length)
			len = length;	/* puke ! */
		/* This is a data packet */
		fputs("] ", stdout);
		do_ppp_print(p, len, len);
		return;
	}

	p += 6;
	length -= 6;
	if (len > length)
		len = length;	/* puke ! */

	/*
	 * A PPPoE tag:
	 *
	 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * |          TAG_TYPE             |        TAG_LENGTH             |
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * |          TAG_VALUE ...                                        ~
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 */

	while (len >= 4) {
		tag = ntohs(*(u_short *)p);
		tlen = ntohs(*(u_short *)(p + 2));

		fputs(" [", stdout);
		for (f = sizeof tagnames / sizeof tagnames[0] - 1; f >= 0; f--)
			if (tagnames[f].tag == tag) {
				asc = tagnames[f].isascii;
				fputs(tagnames[f].name, stdout);
        			break;
      			}

		if (f == -1) {
			printf("<0x%04x>", tag);
			asc = -1;
		}

		p += 4;
		if (tlen > 0) {
			if (asc == -1) {
				for (f = 0; f < tlen; f++)
					if (!isascii(p[f]))
						break;
				asc = f == tlen;
			}
			fputc(' ', stdout);
			if (asc)
				printf("%.*s", (int)tlen, p);
			else for (f = 0; f < tlen; f++)
				printf("%02x", p[f]);
		}
		fputc(']', stdout);

		p += tlen;
		len -= tlen + 4;
	}
}

/*
 * Actually do the job
 */
static void
do_ppp_print(const u_char *p, u_int length, u_int caplen)
{
	if (eflag)
		ppp_hdlc_print(p, length);

	length -= PPP_HDRLEN;

	switch(PPP_PROTOCOL(p)) {
	case PPP_IP:
	case ETHERTYPE_IP:
		ip_print((const u_char *)(p + PPP_HDRLEN), length);
		break;
	case PPP_IPX:
	case ETHERTYPE_IPX:
		ipx_print((const u_char *)(p + PPP_HDRLEN), length);
		break;

	default:
		if(!eflag)
			ppp_hdlc_print(p, length);
		if(!xflag)
			default_print((const u_char *)(p + PPP_HDRLEN),
					caplen - PPP_HDRLEN);
	}

	if (xflag)
		default_print((const u_char *)(p + PPP_HDRLEN),
				caplen - PPP_HDRLEN);
out:
	putchar('\n');
}

/* proto type to string mapping */
static struct tok ptype2str[] = {
	{ PPP_VJC,	"VJC" },
	{ PPP_VJNC,	"VJNC" },
	{ PPP_OSI,	"OSI" },
	{ PPP_LCP,	"LCP" },
	{ PPP_IPCP,	"IPCP" },
	{ 0,		NULL }
};

#define PPP_BSDI_HDRLEN 24

/* BSD/OS specific PPP printer */
void
ppp_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h,
	     register const u_char *p)
{
	register u_int length = h->len;
	register u_int caplen = h->caplen;
	register int hdrlength;
	u_short ptype;

	ts_print(&h->ts);

	if (caplen < PPP_BSDI_HDRLEN) {
		printf("[|ppp]");
		goto out;
	}

	/*
	 * Some printers want to get back at the link level addresses,
	 * and/or check that they're not walking off the end of the packet.
	 * Rather than pass them all the way down, we set these globals.
	 */
	packetp = p;
	snapend = p + caplen;
	hdrlength = 0;

	if (p[0] == PPP_ADDRESS && p[1] == PPP_CONTROL) {
		if (eflag)
			printf("%02x %02x ", p[0], p[1]);
		p += 2;
		hdrlength = 2;
	}

	if (eflag)
		printf("%d ", length);
	/* Retrieve the protocol type */
	if (*p & 01) {
		/* Compressed protocol field */
		ptype = *p;
		if (eflag)
			printf("%02x ", ptype);
		p++;
		hdrlength += 1;
	} else {
		/* Un-compressed protocol field */
		ptype = ntohs(*(u_short *)p);
		if (eflag)
			printf("%04x ", ptype);
		p += 2;
		hdrlength += 2;
	}

	length -= hdrlength;

	if (ptype == PPP_IP)
		ip_print(p, length);
	else
		printf("%s ", tok2str(ptype2str, "proto-#%d", ptype));

	if (xflag)
		default_print((const u_char *)p, caplen - hdrlength);
out:
	putchar('\n');
}