Adding upstream version 4.99.4.upstream/4.99.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 859 insertions, 0 deletions

diff --git a/print-l2tp.c b/print-l2tp.c
new file mode 100644
index 0000000..895efd2
--- /dev/null
+++ b/print-l2tp.c
@@ -0,0 +1,859 @@
+/*
+ * Copyright (c) 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.
+ *
+ * L2TP support contributed by Motonori Shindo (mshindo@mshindo.net)
+ */
+
+/* \summary: Layer Two Tunneling Protocol (L2TP) printer */
+
+/* specification: RFC 2661 */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "netdissect-stdinc.h"
+
+#include "netdissect.h"
+#include "extract.h"
+
+#define L2TP_FLAG_TYPE		0x8000	/* Type (0=Data, 1=Control) */
+#define L2TP_FLAG_LENGTH	0x4000	/* Length */
+#define L2TP_FLAG_SEQUENCE	0x0800	/* Sequence */
+#define L2TP_FLAG_OFFSET	0x0200	/* Offset */
+#define L2TP_FLAG_PRIORITY	0x0100	/* Priority */
+
+#define L2TP_VERSION_MASK	0x000f	/* Version Mask */
+#define L2TP_VERSION_L2F	0x0001	/* L2F */
+#define L2TP_VERSION_L2TP	0x0002	/* L2TP */
+
+#define L2TP_AVP_HDR_FLAG_MANDATORY	0x8000	/* Mandatory Flag */
+#define L2TP_AVP_HDR_FLAG_HIDDEN	0x4000	/* Hidden Flag */
+#define L2TP_AVP_HDR_LEN_MASK		0x03ff	/* Length Mask */
+
+#define L2TP_FRAMING_CAP_SYNC_MASK	0x00000001	/* Synchronous */
+#define L2TP_FRAMING_CAP_ASYNC_MASK	0x00000002	/* Asynchronous */
+
+#define L2TP_FRAMING_TYPE_SYNC_MASK	0x00000001	/* Synchronous */
+#define L2TP_FRAMING_TYPE_ASYNC_MASK	0x00000002	/* Asynchronous */
+
+#define L2TP_BEARER_CAP_DIGITAL_MASK	0x00000001	/* Digital */
+#define L2TP_BEARER_CAP_ANALOG_MASK	0x00000002	/* Analog */
+
+#define L2TP_BEARER_TYPE_DIGITAL_MASK	0x00000001	/* Digital */
+#define L2TP_BEARER_TYPE_ANALOG_MASK	0x00000002	/* Analog */
+
+/* Authen Type */
+#define L2TP_AUTHEN_TYPE_RESERVED	0x0000	/* Reserved */
+#define L2TP_AUTHEN_TYPE_TEXTUAL	0x0001	/* Textual username/password exchange */
+#define L2TP_AUTHEN_TYPE_CHAP		0x0002	/* PPP CHAP */
+#define L2TP_AUTHEN_TYPE_PAP		0x0003	/* PPP PAP */
+#define L2TP_AUTHEN_TYPE_NO_AUTH	0x0004	/* No Authentication */
+#define L2TP_AUTHEN_TYPE_MSCHAPv1	0x0005	/* MSCHAPv1 */
+
+#define L2TP_PROXY_AUTH_ID_MASK		0x00ff
+
+
+#define	L2TP_MSGTYPE_SCCRQ	1  /* Start-Control-Connection-Request */
+#define	L2TP_MSGTYPE_SCCRP	2  /* Start-Control-Connection-Reply */
+#define	L2TP_MSGTYPE_SCCCN	3  /* Start-Control-Connection-Connected */
+#define	L2TP_MSGTYPE_STOPCCN	4  /* Stop-Control-Connection-Notification */
+#define	L2TP_MSGTYPE_HELLO	6  /* Hello */
+#define	L2TP_MSGTYPE_OCRQ	7  /* Outgoing-Call-Request */
+#define	L2TP_MSGTYPE_OCRP	8  /* Outgoing-Call-Reply */
+#define	L2TP_MSGTYPE_OCCN	9  /* Outgoing-Call-Connected */
+#define	L2TP_MSGTYPE_ICRQ	10 /* Incoming-Call-Request */
+#define	L2TP_MSGTYPE_ICRP	11 /* Incoming-Call-Reply */
+#define	L2TP_MSGTYPE_ICCN	12 /* Incoming-Call-Connected */
+#define	L2TP_MSGTYPE_CDN	14 /* Call-Disconnect-Notify */
+#define	L2TP_MSGTYPE_WEN	15 /* WAN-Error-Notify */
+#define	L2TP_MSGTYPE_SLI	16 /* Set-Link-Info */
+
+static const struct tok l2tp_msgtype2str[] = {
+	{ L2TP_MSGTYPE_SCCRQ,	"SCCRQ" },
+	{ L2TP_MSGTYPE_SCCRP,	"SCCRP" },
+	{ L2TP_MSGTYPE_SCCCN,	"SCCCN" },
+	{ L2TP_MSGTYPE_STOPCCN,	"StopCCN" },
+	{ L2TP_MSGTYPE_HELLO,	"HELLO" },
+	{ L2TP_MSGTYPE_OCRQ,	"OCRQ" },
+	{ L2TP_MSGTYPE_OCRP,	"OCRP" },
+	{ L2TP_MSGTYPE_OCCN,	"OCCN" },
+	{ L2TP_MSGTYPE_ICRQ,	"ICRQ" },
+	{ L2TP_MSGTYPE_ICRP,	"ICRP" },
+	{ L2TP_MSGTYPE_ICCN,	"ICCN" },
+	{ L2TP_MSGTYPE_CDN,	"CDN" },
+	{ L2TP_MSGTYPE_WEN,	"WEN" },
+	{ L2TP_MSGTYPE_SLI,	"SLI" },
+	{ 0,			NULL }
+};
+
+#define L2TP_AVP_MSGTYPE		0  /* Message Type */
+#define L2TP_AVP_RESULT_CODE		1  /* Result Code */
+#define L2TP_AVP_PROTO_VER		2  /* Protocol Version */
+#define L2TP_AVP_FRAMING_CAP		3  /* Framing Capabilities */
+#define L2TP_AVP_BEARER_CAP		4  /* Bearer Capabilities */
+#define L2TP_AVP_TIE_BREAKER		5  /* Tie Breaker */
+#define L2TP_AVP_FIRM_VER		6  /* Firmware Revision */
+#define L2TP_AVP_HOST_NAME		7  /* Host Name */
+#define L2TP_AVP_VENDOR_NAME		8  /* Vendor Name */
+#define L2TP_AVP_ASSND_TUN_ID		9  /* Assigned Tunnel ID */
+#define L2TP_AVP_RECV_WIN_SIZE		10 /* Receive Window Size */
+#define L2TP_AVP_CHALLENGE		11 /* Challenge */
+#define L2TP_AVP_Q931_CC		12 /* Q.931 Cause Code */
+#define L2TP_AVP_CHALLENGE_RESP		13 /* Challenge Response */
+#define L2TP_AVP_ASSND_SESS_ID		14 /* Assigned Session ID */
+#define L2TP_AVP_CALL_SER_NUM		15 /* Call Serial Number */
+#define L2TP_AVP_MINIMUM_BPS		16 /* Minimum BPS */
+#define L2TP_AVP_MAXIMUM_BPS		17 /* Maximum BPS */
+#define L2TP_AVP_BEARER_TYPE		18 /* Bearer Type */
+#define L2TP_AVP_FRAMING_TYPE		19 /* Framing Type */
+#define L2TP_AVP_PACKET_PROC_DELAY	20 /* Packet Processing Delay (OBSOLETE) */
+#define L2TP_AVP_CALLED_NUMBER		21 /* Called Number */
+#define L2TP_AVP_CALLING_NUMBER		22 /* Calling Number */
+#define L2TP_AVP_SUB_ADDRESS		23 /* Sub-Address */
+#define L2TP_AVP_TX_CONN_SPEED		24 /* (Tx) Connect Speed */
+#define L2TP_AVP_PHY_CHANNEL_ID		25 /* Physical Channel ID */
+#define L2TP_AVP_INI_RECV_LCP		26 /* Initial Received LCP CONFREQ */
+#define L2TP_AVP_LAST_SENT_LCP		27 /* Last Sent LCP CONFREQ */
+#define L2TP_AVP_LAST_RECV_LCP		28 /* Last Received LCP CONFREQ */
+#define L2TP_AVP_PROXY_AUTH_TYPE	29 /* Proxy Authen Type */
+#define L2TP_AVP_PROXY_AUTH_NAME	30 /* Proxy Authen Name */
+#define L2TP_AVP_PROXY_AUTH_CHAL	31 /* Proxy Authen Challenge */
+#define L2TP_AVP_PROXY_AUTH_ID		32 /* Proxy Authen ID */
+#define L2TP_AVP_PROXY_AUTH_RESP	33 /* Proxy Authen Response */
+#define L2TP_AVP_CALL_ERRORS		34 /* Call Errors */
+#define L2TP_AVP_ACCM			35 /* ACCM */
+#define L2TP_AVP_RANDOM_VECTOR		36 /* Random Vector */
+#define L2TP_AVP_PRIVATE_GRP_ID		37 /* Private Group ID */
+#define L2TP_AVP_RX_CONN_SPEED		38 /* (Rx) Connect Speed */
+#define L2TP_AVP_SEQ_REQUIRED		39 /* Sequencing Required */
+#define L2TP_AVP_PPP_DISCON_CC		46 /* PPP Disconnect Cause Code - RFC 3145 */
+
+static const struct tok l2tp_avp2str[] = {
+	{ L2TP_AVP_MSGTYPE,		"MSGTYPE" },
+	{ L2TP_AVP_RESULT_CODE,		"RESULT_CODE" },
+	{ L2TP_AVP_PROTO_VER,		"PROTO_VER" },
+	{ L2TP_AVP_FRAMING_CAP,		"FRAMING_CAP" },
+	{ L2TP_AVP_BEARER_CAP,		"BEARER_CAP" },
+	{ L2TP_AVP_TIE_BREAKER,		"TIE_BREAKER" },
+	{ L2TP_AVP_FIRM_VER,		"FIRM_VER" },
+	{ L2TP_AVP_HOST_NAME,		"HOST_NAME" },
+	{ L2TP_AVP_VENDOR_NAME,		"VENDOR_NAME" },
+	{ L2TP_AVP_ASSND_TUN_ID,	"ASSND_TUN_ID" },
+	{ L2TP_AVP_RECV_WIN_SIZE,	"RECV_WIN_SIZE" },
+	{ L2TP_AVP_CHALLENGE,		"CHALLENGE" },
+	{ L2TP_AVP_Q931_CC,		"Q931_CC", },
+	{ L2TP_AVP_CHALLENGE_RESP,	"CHALLENGE_RESP" },
+	{ L2TP_AVP_ASSND_SESS_ID,	"ASSND_SESS_ID" },
+	{ L2TP_AVP_CALL_SER_NUM,	"CALL_SER_NUM" },
+	{ L2TP_AVP_MINIMUM_BPS,		"MINIMUM_BPS" },
+	{ L2TP_AVP_MAXIMUM_BPS,		"MAXIMUM_BPS" },
+	{ L2TP_AVP_BEARER_TYPE,		"BEARER_TYPE" },
+	{ L2TP_AVP_FRAMING_TYPE,	"FRAMING_TYPE" },
+	{ L2TP_AVP_PACKET_PROC_DELAY,	"PACKET_PROC_DELAY" },
+	{ L2TP_AVP_CALLED_NUMBER,	"CALLED_NUMBER" },
+	{ L2TP_AVP_CALLING_NUMBER,	"CALLING_NUMBER" },
+	{ L2TP_AVP_SUB_ADDRESS,		"SUB_ADDRESS" },
+	{ L2TP_AVP_TX_CONN_SPEED,	"TX_CONN_SPEED" },
+	{ L2TP_AVP_PHY_CHANNEL_ID,	"PHY_CHANNEL_ID" },
+	{ L2TP_AVP_INI_RECV_LCP,	"INI_RECV_LCP" },
+	{ L2TP_AVP_LAST_SENT_LCP,	"LAST_SENT_LCP" },
+	{ L2TP_AVP_LAST_RECV_LCP,	"LAST_RECV_LCP" },
+	{ L2TP_AVP_PROXY_AUTH_TYPE,	"PROXY_AUTH_TYPE" },
+	{ L2TP_AVP_PROXY_AUTH_NAME,	"PROXY_AUTH_NAME" },
+	{ L2TP_AVP_PROXY_AUTH_CHAL,	"PROXY_AUTH_CHAL" },
+	{ L2TP_AVP_PROXY_AUTH_ID,	"PROXY_AUTH_ID" },
+	{ L2TP_AVP_PROXY_AUTH_RESP,	"PROXY_AUTH_RESP" },
+	{ L2TP_AVP_CALL_ERRORS,		"CALL_ERRORS" },
+	{ L2TP_AVP_ACCM,		"ACCM" },
+	{ L2TP_AVP_RANDOM_VECTOR,	"RANDOM_VECTOR" },
+	{ L2TP_AVP_PRIVATE_GRP_ID,	"PRIVATE_GRP_ID" },
+	{ L2TP_AVP_RX_CONN_SPEED,	"RX_CONN_SPEED" },
+	{ L2TP_AVP_SEQ_REQUIRED,	"SEQ_REQUIRED" },
+	{ L2TP_AVP_PPP_DISCON_CC,	"PPP_DISCON_CC" },
+	{ 0,				NULL }
+};
+
+static const struct tok l2tp_authentype2str[] = {
+	{ L2TP_AUTHEN_TYPE_RESERVED,	"Reserved" },
+	{ L2TP_AUTHEN_TYPE_TEXTUAL,	"Textual" },
+	{ L2TP_AUTHEN_TYPE_CHAP,	"CHAP" },
+	{ L2TP_AUTHEN_TYPE_PAP,		"PAP" },
+	{ L2TP_AUTHEN_TYPE_NO_AUTH,	"No Auth" },
+	{ L2TP_AUTHEN_TYPE_MSCHAPv1,	"MS-CHAPv1" },
+	{ 0,				NULL }
+};
+
+#define L2TP_PPP_DISCON_CC_DIRECTION_GLOBAL	0
+#define L2TP_PPP_DISCON_CC_DIRECTION_AT_PEER	1
+#define L2TP_PPP_DISCON_CC_DIRECTION_AT_LOCAL	2
+
+static const struct tok l2tp_cc_direction2str[] = {
+	{ L2TP_PPP_DISCON_CC_DIRECTION_GLOBAL,	"global error" },
+	{ L2TP_PPP_DISCON_CC_DIRECTION_AT_PEER,	"at peer" },
+	{ L2TP_PPP_DISCON_CC_DIRECTION_AT_LOCAL,"at local" },
+	{ 0,					NULL }
+};
+
+#if 0
+static char *l2tp_result_code_StopCCN[] = {
+         "Reserved",
+         "General request to clear control connection",
+         "General error--Error Code indicates the problem",
+         "Control channel already exists",
+         "Requester is not authorized to establish a control channel",
+         "The protocol version of the requester is not supported",
+         "Requester is being shut down",
+         "Finite State Machine error"
+#define L2TP_MAX_RESULT_CODE_STOPCC_INDEX	8
+};
+#endif
+
+#if 0
+static char *l2tp_result_code_CDN[] = {
+	"Reserved",
+	"Call disconnected due to loss of carrier",
+	"Call disconnected for the reason indicated in error code",
+	"Call disconnected for administrative reasons",
+	"Call failed due to lack of appropriate facilities being "
+	"available (temporary condition)",
+	"Call failed due to lack of appropriate facilities being "
+	"available (permanent condition)",
+	"Invalid destination",
+	"Call failed due to no carrier detected",
+	"Call failed due to detection of a busy signal",
+	"Call failed due to lack of a dial tone",
+	"Call was not established within time allotted by LAC",
+	"Call was connected but no appropriate framing was detected"
+#define L2TP_MAX_RESULT_CODE_CDN_INDEX	12
+};
+#endif
+
+#if 0
+static char *l2tp_error_code_general[] = {
+	"No general error",
+	"No control connection exists yet for this LAC-LNS pair",
+	"Length is wrong",
+	"One of the field values was out of range or "
+	"reserved field was non-zero"
+	"Insufficient resources to handle this operation now",
+	"The Session ID is invalid in this context",
+	"A generic vendor-specific error occurred in the LAC",
+	"Try another"
+#define L2TP_MAX_ERROR_CODE_GENERAL_INDEX	8
+};
+#endif
+
+/******************************/
+/* generic print out routines */
+/******************************/
+static void
+print_string(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	u_int i;
+	for (i=0; i<length; i++) {
+		fn_print_char(ndo, GET_U_1(dat));
+		dat++;
+	}
+}
+
+static void
+print_octets(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	u_int i;
+	for (i=0; i<length; i++) {
+		ND_PRINT("%02x", GET_U_1(dat));
+		dat++;
+	}
+}
+
+static void
+print_16bits_val(netdissect_options *ndo, const uint8_t *dat)
+{
+	ND_PRINT("%u", GET_BE_U_2(dat));
+}
+
+static void
+print_32bits_val(netdissect_options *ndo, const uint8_t *dat)
+{
+	ND_PRINT("%u", GET_BE_U_4(dat));
+}
+
+/***********************************/
+/* AVP-specific print out routines */
+/***********************************/
+static void
+l2tp_msgtype_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 2) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	ND_PRINT("%s", tok2str(l2tp_msgtype2str, "MSGTYPE-#%u",
+	    GET_BE_U_2(dat)));
+}
+
+static void
+l2tp_result_code_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	/* Result Code */
+	if (length < 2) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	ND_PRINT("%u", GET_BE_U_2(dat));
+	dat += 2;
+	length -= 2;
+
+	/* Error Code (opt) */
+	if (length == 0)
+		return;
+	if (length < 2) {
+		ND_PRINT(" AVP too short");
+		return;
+	}
+	ND_PRINT("/%u", GET_BE_U_2(dat));
+	dat += 2;
+	length -= 2;
+
+	/* Error Message (opt) */
+	if (length == 0)
+		return;
+	ND_PRINT(" ");
+	print_string(ndo, dat, length);
+}
+
+static void
+l2tp_proto_ver_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 2) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	ND_PRINT("%u.%u", (GET_BE_U_2(dat) >> 8),
+		  (GET_BE_U_2(dat) & 0xff));
+}
+
+static void
+l2tp_framing_cap_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	if (GET_BE_U_4(dat) &  L2TP_FRAMING_CAP_ASYNC_MASK) {
+		ND_PRINT("A");
+	}
+	if (GET_BE_U_4(dat) &  L2TP_FRAMING_CAP_SYNC_MASK) {
+		ND_PRINT("S");
+	}
+}
+
+static void
+l2tp_bearer_cap_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	if (GET_BE_U_4(dat) &  L2TP_BEARER_CAP_ANALOG_MASK) {
+		ND_PRINT("A");
+	}
+	if (GET_BE_U_4(dat) &  L2TP_BEARER_CAP_DIGITAL_MASK) {
+		ND_PRINT("D");
+	}
+}
+
+static void
+l2tp_q931_cc_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 3) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	print_16bits_val(ndo, dat);
+	ND_PRINT(", %02x", GET_U_1(dat + 2));
+	dat += 3;
+	length -= 3;
+	if (length != 0) {
+		ND_PRINT(" ");
+		print_string(ndo, dat, length);
+	}
+}
+
+static void
+l2tp_bearer_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	if (GET_BE_U_4(dat) &  L2TP_BEARER_TYPE_ANALOG_MASK) {
+		ND_PRINT("A");
+	}
+	if (GET_BE_U_4(dat) &  L2TP_BEARER_TYPE_DIGITAL_MASK) {
+		ND_PRINT("D");
+	}
+}
+
+static void
+l2tp_framing_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	if (GET_BE_U_4(dat) &  L2TP_FRAMING_TYPE_ASYNC_MASK) {
+		ND_PRINT("A");
+	}
+	if (GET_BE_U_4(dat) &  L2TP_FRAMING_TYPE_SYNC_MASK) {
+		ND_PRINT("S");
+	}
+}
+
+static void
+l2tp_packet_proc_delay_print(netdissect_options *ndo)
+{
+	ND_PRINT("obsolete");
+}
+
+static void
+l2tp_proxy_auth_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 2) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	ND_PRINT("%s", tok2str(l2tp_authentype2str,
+			     "AuthType-#%u", GET_BE_U_2(dat)));
+}
+
+static void
+l2tp_proxy_auth_id_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 2) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	ND_PRINT("%u", GET_BE_U_2(dat) & L2TP_PROXY_AUTH_ID_MASK);
+}
+
+static void
+l2tp_call_errors_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	uint32_t val;
+
+	if (length < 2) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	dat += 2;	/* skip "Reserved" */
+	length -= 2;
+
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	val = GET_BE_U_4(dat); dat += 4; length -= 4;
+	ND_PRINT("CRCErr=%u ", val);
+
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	val = GET_BE_U_4(dat); dat += 4; length -= 4;
+	ND_PRINT("FrameErr=%u ", val);
+
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	val = GET_BE_U_4(dat); dat += 4; length -= 4;
+	ND_PRINT("HardOver=%u ", val);
+
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	val = GET_BE_U_4(dat); dat += 4; length -= 4;
+	ND_PRINT("BufOver=%u ", val);
+
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	val = GET_BE_U_4(dat); dat += 4; length -= 4;
+	ND_PRINT("Timeout=%u ", val);
+
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	val = GET_BE_U_4(dat); dat += 4; length -= 4;
+	ND_PRINT("AlignErr=%u ", val);
+}
+
+static void
+l2tp_accm_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	uint32_t val;
+
+	if (length < 2) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	dat += 2;	/* skip "Reserved" */
+	length -= 2;
+
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	val = GET_BE_U_4(dat); dat += 4; length -= 4;
+	ND_PRINT("send=%08x ", val);
+
+	if (length < 4) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	val = GET_BE_U_4(dat); dat += 4; length -= 4;
+	ND_PRINT("recv=%08x ", val);
+}
+
+static void
+l2tp_ppp_discon_cc_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	if (length < 5) {
+		ND_PRINT("AVP too short");
+		return;
+	}
+	/* Disconnect Code */
+	ND_PRINT("%04x, ", GET_BE_U_2(dat));
+	dat += 2;
+	length -= 2;
+	/* Control Protocol Number */
+	ND_PRINT("%04x ",  GET_BE_U_2(dat));
+	dat += 2;
+	length -= 2;
+	/* Direction */
+	ND_PRINT("%s", tok2str(l2tp_cc_direction2str,
+			     "Direction-#%u", GET_U_1(dat)));
+	dat++;
+	length--;
+
+	if (length != 0) {
+		ND_PRINT(" ");
+		print_string(ndo, (const u_char *)dat, length);
+	}
+}
+
+static u_int
+l2tp_avp_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	u_int len;
+	uint16_t attr_type;
+	int hidden = FALSE;
+
+	ND_PRINT(" ");
+	/* Flags & Length */
+	len = GET_BE_U_2(dat) & L2TP_AVP_HDR_LEN_MASK;
+
+	/* If it is not long enough to contain the header, we'll give up. */
+	if (len < 6)
+		goto trunc;
+
+	/* If it goes past the end of the remaining length of the packet,
+	   we'll give up. */
+	if (len > (u_int)length)
+		goto trunc;
+
+	/* If it goes past the end of the remaining length of the captured
+	   data, we'll give up. */
+	ND_TCHECK_LEN(dat, len);
+
+	/*
+	 * After this point, we don't need to check whether we go past
+	 * the length of the captured data; however, we *do* need to
+	 * check whether we go past the end of the AVP.
+	 */
+
+	if (GET_BE_U_2(dat) & L2TP_AVP_HDR_FLAG_MANDATORY) {
+		ND_PRINT("*");
+	}
+	if (GET_BE_U_2(dat) & L2TP_AVP_HDR_FLAG_HIDDEN) {
+		hidden = TRUE;
+		ND_PRINT("?");
+	}
+	dat += 2;
+
+	if (GET_BE_U_2(dat)) {
+		/* Vendor Specific Attribute */
+	        ND_PRINT("VENDOR%04x:", GET_BE_U_2(dat)); dat += 2;
+		ND_PRINT("ATTR%04x", GET_BE_U_2(dat)); dat += 2;
+		ND_PRINT("(");
+		print_octets(ndo, dat, len-6);
+		ND_PRINT(")");
+	} else {
+		/* IETF-defined Attributes */
+		dat += 2;
+		attr_type = GET_BE_U_2(dat); dat += 2;
+		ND_PRINT("%s", tok2str(l2tp_avp2str, "AVP-#%u", attr_type));
+		ND_PRINT("(");
+		if (hidden) {
+			ND_PRINT("???");
+		} else {
+			switch (attr_type) {
+			case L2TP_AVP_MSGTYPE:
+				l2tp_msgtype_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_RESULT_CODE:
+				l2tp_result_code_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_PROTO_VER:
+				l2tp_proto_ver_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_FRAMING_CAP:
+				l2tp_framing_cap_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_BEARER_CAP:
+				l2tp_bearer_cap_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_TIE_BREAKER:
+				if (len-6 < 8) {
+					ND_PRINT("AVP too short");
+					break;
+				}
+				print_octets(ndo, dat, 8);
+				break;
+			case L2TP_AVP_FIRM_VER:
+			case L2TP_AVP_ASSND_TUN_ID:
+			case L2TP_AVP_RECV_WIN_SIZE:
+			case L2TP_AVP_ASSND_SESS_ID:
+				if (len-6 < 2) {
+					ND_PRINT("AVP too short");
+					break;
+				}
+				print_16bits_val(ndo, dat);
+				break;
+			case L2TP_AVP_HOST_NAME:
+			case L2TP_AVP_VENDOR_NAME:
+			case L2TP_AVP_CALLING_NUMBER:
+			case L2TP_AVP_CALLED_NUMBER:
+			case L2TP_AVP_SUB_ADDRESS:
+			case L2TP_AVP_PROXY_AUTH_NAME:
+			case L2TP_AVP_PRIVATE_GRP_ID:
+				print_string(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_CHALLENGE:
+			case L2TP_AVP_INI_RECV_LCP:
+			case L2TP_AVP_LAST_SENT_LCP:
+			case L2TP_AVP_LAST_RECV_LCP:
+			case L2TP_AVP_PROXY_AUTH_CHAL:
+			case L2TP_AVP_PROXY_AUTH_RESP:
+			case L2TP_AVP_RANDOM_VECTOR:
+				print_octets(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_Q931_CC:
+				l2tp_q931_cc_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_CHALLENGE_RESP:
+				if (len-6 < 16) {
+					ND_PRINT("AVP too short");
+					break;
+				}
+				print_octets(ndo, dat, 16);
+				break;
+			case L2TP_AVP_CALL_SER_NUM:
+			case L2TP_AVP_MINIMUM_BPS:
+			case L2TP_AVP_MAXIMUM_BPS:
+			case L2TP_AVP_TX_CONN_SPEED:
+			case L2TP_AVP_PHY_CHANNEL_ID:
+			case L2TP_AVP_RX_CONN_SPEED:
+				if (len-6 < 4) {
+					ND_PRINT("AVP too short");
+					break;
+				}
+				print_32bits_val(ndo, dat);
+				break;
+			case L2TP_AVP_BEARER_TYPE:
+				l2tp_bearer_type_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_FRAMING_TYPE:
+				l2tp_framing_type_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_PACKET_PROC_DELAY:
+				l2tp_packet_proc_delay_print(ndo);
+				break;
+			case L2TP_AVP_PROXY_AUTH_TYPE:
+				l2tp_proxy_auth_type_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_PROXY_AUTH_ID:
+				l2tp_proxy_auth_id_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_CALL_ERRORS:
+				l2tp_call_errors_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_ACCM:
+				l2tp_accm_print(ndo, dat, len-6);
+				break;
+			case L2TP_AVP_SEQ_REQUIRED:
+				break;	/* No Attribute Value */
+			case L2TP_AVP_PPP_DISCON_CC:
+				l2tp_ppp_discon_cc_print(ndo, dat, len-6);
+				break;
+			default:
+				break;
+			}
+		}
+		ND_PRINT(")");
+	}
+
+	return (len);
+
+ trunc:
+	nd_print_trunc(ndo);
+	return (0);
+}
+
+
+void
+l2tp_print(netdissect_options *ndo, const u_char *dat, u_int length)
+{
+	const u_char *ptr = dat;
+	u_int cnt = 0;			/* total octets consumed */
+	uint16_t pad;
+	int flag_t, flag_l, flag_s, flag_o;
+	uint16_t l2tp_len;
+
+	ndo->ndo_protocol = "l2tp";
+	flag_t = flag_l = flag_s = flag_o = FALSE;
+
+	if ((GET_BE_U_2(ptr) & L2TP_VERSION_MASK) == L2TP_VERSION_L2TP) {
+		ND_PRINT(" l2tp:");
+	} else if ((GET_BE_U_2(ptr) & L2TP_VERSION_MASK) == L2TP_VERSION_L2F) {
+		ND_PRINT(" l2f:");
+		return;		/* nothing to do */
+	} else {
+		ND_PRINT(" Unknown Version, neither L2F(1) nor L2TP(2)");
+		return;		/* nothing we can do */
+	}
+
+	ND_PRINT("[");
+	if (GET_BE_U_2(ptr) & L2TP_FLAG_TYPE) {
+		flag_t = TRUE;
+		ND_PRINT("T");
+	}
+	if (GET_BE_U_2(ptr) & L2TP_FLAG_LENGTH) {
+		flag_l = TRUE;
+		ND_PRINT("L");
+	}
+	if (GET_BE_U_2(ptr) & L2TP_FLAG_SEQUENCE) {
+		flag_s = TRUE;
+		ND_PRINT("S");
+	}
+	if (GET_BE_U_2(ptr) & L2TP_FLAG_OFFSET) {
+		flag_o = TRUE;
+		ND_PRINT("O");
+	}
+	if (GET_BE_U_2(ptr) & L2TP_FLAG_PRIORITY)
+		ND_PRINT("P");
+	ND_PRINT("]");
+
+	ptr += 2;
+	cnt += 2;
+
+	if (flag_l) {
+		l2tp_len = GET_BE_U_2(ptr);
+		ptr += 2;
+		cnt += 2;
+	} else {
+		l2tp_len = 0;
+	}
+	/* Tunnel ID */
+	ND_PRINT("(%u/", GET_BE_U_2(ptr));
+	ptr += 2;
+	cnt += 2;
+	/* Session ID */
+	ND_PRINT("%u)",  GET_BE_U_2(ptr));
+	ptr += 2;
+	cnt += 2;
+
+	if (flag_s) {
+		ND_PRINT("Ns=%u,", GET_BE_U_2(ptr));
+		ptr += 2;
+		cnt += 2;
+		ND_PRINT("Nr=%u",  GET_BE_U_2(ptr));
+		ptr += 2;
+		cnt += 2;
+	}
+
+	if (flag_o) {	/* Offset Size */
+		pad =  GET_BE_U_2(ptr);
+		/* Offset padding octets in packet buffer? */
+		ND_TCHECK_LEN(ptr + 2, pad);
+		ptr += (2 + pad);
+		cnt += (2 + pad);
+	}
+
+	if (flag_l) {
+		if (length < l2tp_len) {
+			ND_PRINT(" Length %u larger than packet", l2tp_len);
+			return;
+		}
+		length = l2tp_len;
+	}
+	if (length < cnt) {
+		ND_PRINT(" Length %u smaller than header length", length);
+		return;
+	}
+	if (flag_t) {
+		if (!flag_l) {
+			ND_PRINT(" No length");
+			return;
+		}
+		if (length - cnt == 0) {
+			ND_PRINT(" ZLB");
+		} else {
+			/*
+			 * Print AVPs.
+			 */
+			while (length - cnt != 0) {
+				u_int avp_length;
+
+				avp_length = l2tp_avp_print(ndo, ptr, length - cnt);
+				if (avp_length == 0) {
+					/*
+					 * Truncated.
+					 */
+					break;
+				}
+				cnt += avp_length;
+				ptr += avp_length;
+			}
+		}
+	} else {
+		ND_PRINT(" {");
+		ppp_print(ndo, ptr, length - cnt);
+		ND_PRINT("}");
+	}
+	return;
+trunc:
+	nd_print_trunc(ndo);
+}