*/
-#ifndef lint
-static const char rcsid[] _U_ =
- "@(#) $Header: /tcpdump/master/tcpdump/print-l2tp.c,v 1.20 2006-06-23 02:03:09 hannes Exp $";
-#endif
+/* \summary: Layer Two Tunneling Protocol (L2TP) printer */
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
+/* specification: RFC 2661 */
-#include <tcpdump-stdinc.h>
+#include <config.h>
-#include <stdio.h>
+#include "netdissect-stdinc.h"
-#include "l2tp.h"
-#include "interface.h"
+#define ND_LONGJMP_FROM_TCHECK
+#include "netdissect.h"
#include "extract.h"
-static char tstr[] = " [|l2tp]";
+#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_WEN 15 /* WAN-Error-Notify */
#define L2TP_MSGTYPE_SLI 16 /* Set-Link-Info */
-static struct tok l2tp_msgtype2str[] = {
- { L2TP_MSGTYPE_SCCRQ, "SCCRQ" },
+static const struct tok l2tp_msgtype2str[] = {
+ { L2TP_MSGTYPE_SCCRQ, "SCCRQ" },
{ L2TP_MSGTYPE_SCCRP, "SCCRP" },
{ L2TP_MSGTYPE_SCCCN, "SCCCN" },
{ L2TP_MSGTYPE_STOPCCN, "StopCCN" },
#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_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_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_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_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 */
+#define L2TP_AVP_SEQ_REQUIRED 39 /* Sequencing Required */
+#define L2TP_AVP_PPP_DISCON_CC 46 /* PPP Disconnect Cause Code - RFC 3145 */
-static struct tok l2tp_avp2str[] = {
+static const struct tok l2tp_avp2str[] = {
{ L2TP_AVP_MSGTYPE, "MSGTYPE" },
{ L2TP_AVP_RESULT_CODE, "RESULT_CODE" },
{ L2TP_AVP_PROTO_VER, "PROTO_VER" },
{ 0, NULL }
};
-static struct tok l2tp_authentype2str[] = {
+static const struct tok l2tp_authentype2str[] = {
{ L2TP_AUTHEN_TYPE_RESERVED, "Reserved" },
{ L2TP_AUTHEN_TYPE_TEXTUAL, "Textual" },
{ L2TP_AUTHEN_TYPE_CHAP, "CHAP" },
#define L2TP_PPP_DISCON_CC_DIRECTION_AT_PEER 1
#define L2TP_PPP_DISCON_CC_DIRECTION_AT_LOCAL 2
-static struct tok l2tp_cc_direction2str[] = {
+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" },
"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 " \
+ "Call failed due to lack of appropriate facilities being "
"available (temporary condition)",
- "Call failed due to lack of appropriate facilities being " \
+ "Call failed due to lack of appropriate facilities being "
"available (permanent condition)",
"Invalid destination",
"Call failed due to no carrier detected",
"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 " \
+ "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",
/* generic print out routines */
/******************************/
static void
-print_string(const u_char *dat, u_int length)
+print_octets(netdissect_options *ndo, const u_char *dat, u_int length)
{
u_int i;
for (i=0; i<length; i++) {
- printf("%c", *dat++);
+ ND_PRINT("%02x", GET_U_1(dat));
+ dat++;
}
}
static void
-print_octets(const u_char *dat, u_int length)
+print_16bits_val(netdissect_options *ndo, const uint8_t *dat)
{
- u_int i;
- for (i=0; i<length; i++) {
- printf("%02x", *dat++);
- }
+ ND_PRINT("%u", GET_BE_U_2(dat));
}
static void
-print_16bits_val(const u_int16_t *dat)
+print_32bits_val(netdissect_options *ndo, const uint8_t *dat)
{
- printf("%u", EXTRACT_16BITS(dat));
-}
-
-static void
-print_32bits_val(const u_int32_t *dat)
-{
- printf("%lu", (u_long)EXTRACT_32BITS(dat));
+ ND_PRINT("%u", GET_BE_U_4(dat));
}
/***********************************/
/* AVP-specific print out routines */
/***********************************/
static void
-l2tp_msgtype_print(const u_char *dat)
+l2tp_msgtype_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int16_t *ptr = (u_int16_t*)dat;
-
- printf("%s", tok2str(l2tp_msgtype2str, "MSGTYPE-#%u",
- EXTRACT_16BITS(ptr)));
+ 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(const u_char *dat, u_int length)
+l2tp_result_code_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int16_t *ptr = (u_int16_t *)dat;
-
- printf("%u", EXTRACT_16BITS(ptr)); ptr++; /* Result Code */
- if (length > 2) { /* Error Code (opt) */
- printf("/%u", EXTRACT_16BITS(ptr)); ptr++;
+ /* Result Code */
+ if (length < 2) {
+ ND_PRINT("AVP too short");
+ return;
}
- if (length > 4) { /* Error Message (opt) */
- printf(" ");
- print_string((u_char *)ptr, length - 4);
+ 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(" ");
+ nd_printjn(ndo, dat, length);
}
static void
-l2tp_proto_ver_print(const u_int16_t *dat)
+l2tp_proto_ver_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- printf("%u.%u", (EXTRACT_16BITS(dat) >> 8),
- (EXTRACT_16BITS(dat) & 0xff));
+ 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(const u_char *dat)
+l2tp_framing_cap_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int32_t *ptr = (u_int32_t *)dat;
-
- if (EXTRACT_32BITS(ptr) & L2TP_FRAMING_CAP_ASYNC_MASK) {
- printf("A");
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ if (GET_BE_U_4(dat) & L2TP_FRAMING_CAP_ASYNC_MASK) {
+ ND_PRINT("A");
}
- if (EXTRACT_32BITS(ptr) & L2TP_FRAMING_CAP_SYNC_MASK) {
- printf("S");
+ if (GET_BE_U_4(dat) & L2TP_FRAMING_CAP_SYNC_MASK) {
+ ND_PRINT("S");
}
}
static void
-l2tp_bearer_cap_print(const u_char *dat)
+l2tp_bearer_cap_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int32_t *ptr = (u_int32_t *)dat;
-
- if (EXTRACT_32BITS(ptr) & L2TP_BEARER_CAP_ANALOG_MASK) {
- printf("A");
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ if (GET_BE_U_4(dat) & L2TP_BEARER_CAP_ANALOG_MASK) {
+ ND_PRINT("A");
}
- if (EXTRACT_32BITS(ptr) & L2TP_BEARER_CAP_DIGITAL_MASK) {
- printf("D");
+ if (GET_BE_U_4(dat) & L2TP_BEARER_CAP_DIGITAL_MASK) {
+ ND_PRINT("D");
}
}
static void
-l2tp_q931_cc_print(const u_char *dat, u_int length)
+l2tp_q931_cc_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- print_16bits_val((u_int16_t *)dat);
- printf(", %02x", dat[2]);
- if (length > 3) {
- printf(" ");
- print_string(dat+3, length-3);
+ 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(" ");
+ nd_printjn(ndo, dat, length);
}
}
static void
-l2tp_bearer_type_print(const u_char *dat)
+l2tp_bearer_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int32_t *ptr = (u_int32_t *)dat;
-
- if (EXTRACT_32BITS(ptr) & L2TP_BEARER_TYPE_ANALOG_MASK) {
- printf("A");
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ if (GET_BE_U_4(dat) & L2TP_BEARER_TYPE_ANALOG_MASK) {
+ ND_PRINT("A");
}
- if (EXTRACT_32BITS(ptr) & L2TP_BEARER_TYPE_DIGITAL_MASK) {
- printf("D");
+ if (GET_BE_U_4(dat) & L2TP_BEARER_TYPE_DIGITAL_MASK) {
+ ND_PRINT("D");
}
}
static void
-l2tp_framing_type_print(const u_char *dat)
+l2tp_framing_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int32_t *ptr = (u_int32_t *)dat;
-
- if (EXTRACT_32BITS(ptr) & L2TP_FRAMING_TYPE_ASYNC_MASK) {
- printf("A");
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ if (GET_BE_U_4(dat) & L2TP_FRAMING_TYPE_ASYNC_MASK) {
+ ND_PRINT("A");
}
- if (EXTRACT_32BITS(ptr) & L2TP_FRAMING_TYPE_SYNC_MASK) {
- printf("S");
+ if (GET_BE_U_4(dat) & L2TP_FRAMING_TYPE_SYNC_MASK) {
+ ND_PRINT("S");
}
}
static void
-l2tp_packet_proc_delay_print(void)
+l2tp_packet_proc_delay_print(netdissect_options *ndo)
{
- printf("obsolete");
+ ND_PRINT("obsolete");
}
static void
-l2tp_proxy_auth_type_print(const u_char *dat)
+l2tp_proxy_auth_type_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int16_t *ptr = (u_int16_t *)dat;
-
- printf("%s", tok2str(l2tp_authentype2str,
- "AuthType-#%u", EXTRACT_16BITS(ptr)));
+ 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(const u_char *dat)
+l2tp_proxy_auth_id_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int16_t *ptr = (u_int16_t *)dat;
-
- printf("%u", EXTRACT_16BITS(ptr) & L2TP_PROXY_AUTH_ID_MASK);
+ 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(const u_char *dat)
+l2tp_call_errors_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int16_t *ptr = (u_int16_t *)dat;
- u_int16_t val_h, val_l;
+ uint32_t val;
- ptr++; /* skip "Reserved" */
+ if (length < 2) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ dat += 2; /* skip "Reserved" */
+ length -= 2;
- val_h = EXTRACT_16BITS(ptr); ptr++;
- val_l = EXTRACT_16BITS(ptr); ptr++;
- printf("CRCErr=%u ", (val_h<<16) + val_l);
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ val = GET_BE_U_4(dat); dat += 4; length -= 4;
+ ND_PRINT("CRCErr=%u ", val);
- val_h = EXTRACT_16BITS(ptr); ptr++;
- val_l = EXTRACT_16BITS(ptr); ptr++;
- printf("FrameErr=%u ", (val_h<<16) + val_l);
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ val = GET_BE_U_4(dat); dat += 4; length -= 4;
+ ND_PRINT("FrameErr=%u ", val);
- val_h = EXTRACT_16BITS(ptr); ptr++;
- val_l = EXTRACT_16BITS(ptr); ptr++;
- printf("HardOver=%u ", (val_h<<16) + val_l);
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ val = GET_BE_U_4(dat); dat += 4; length -= 4;
+ ND_PRINT("HardOver=%u ", val);
- val_h = EXTRACT_16BITS(ptr); ptr++;
- val_l = EXTRACT_16BITS(ptr); ptr++;
- printf("BufOver=%u ", (val_h<<16) + val_l);
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ val = GET_BE_U_4(dat); dat += 4; length -= 4;
+ ND_PRINT("BufOver=%u ", val);
- val_h = EXTRACT_16BITS(ptr); ptr++;
- val_l = EXTRACT_16BITS(ptr); ptr++;
- printf("Timeout=%u ", (val_h<<16) + val_l);
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ val = GET_BE_U_4(dat); dat += 4; length -= 4;
+ ND_PRINT("Timeout=%u ", val);
- val_h = EXTRACT_16BITS(ptr); ptr++;
- val_l = EXTRACT_16BITS(ptr); ptr++;
- printf("AlignErr=%u ", (val_h<<16) + val_l);
+ 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(const u_char *dat)
+l2tp_accm_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int16_t *ptr = (u_int16_t *)dat;
- u_int16_t val_h, val_l;
+ uint32_t val;
- ptr++; /* skip "Reserved" */
+ if (length < 2) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ dat += 2; /* skip "Reserved" */
+ length -= 2;
- val_h = EXTRACT_16BITS(ptr); ptr++;
- val_l = EXTRACT_16BITS(ptr); ptr++;
- printf("send=%08x ", (val_h<<16) + val_l);
+ if (length < 4) {
+ ND_PRINT("AVP too short");
+ return;
+ }
+ val = GET_BE_U_4(dat); dat += 4; length -= 4;
+ ND_PRINT("send=%08x ", val);
- val_h = EXTRACT_16BITS(ptr); ptr++;
- val_l = EXTRACT_16BITS(ptr); ptr++;
- printf("recv=%08x ", (val_h<<16) + val_l);
+ 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(const u_char *dat, u_int length)
+l2tp_ppp_discon_cc_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
- u_int16_t *ptr = (u_int16_t *)dat;
-
- printf("%04x, ", EXTRACT_16BITS(ptr)); ptr++; /* Disconnect Code */
- printf("%04x ", EXTRACT_16BITS(ptr)); ptr++; /* Control Protocol Number */
- printf("%s", tok2str(l2tp_cc_direction2str,
- "Direction-#%u", *((u_char *)ptr++)));
-
- if (length > 5) {
- printf(" ");
- print_string((const u_char *)ptr, length-5);
+ 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(" ");
+ nd_printjn(ndo, (const u_char *)dat, length);
}
}
-static void
-l2tp_avp_print(const u_char *dat, int length)
+static u_int
+l2tp_avp_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
u_int len;
- const u_int16_t *ptr = (u_int16_t *)dat;
- u_int16_t attr_type;
+ uint16_t attr_type;
int hidden = FALSE;
- if (length <= 0) {
- return;
- }
-
- printf(" ");
-
- TCHECK(*ptr); /* Flags & Length */
- len = EXTRACT_16BITS(ptr) & L2TP_AVP_HDR_LEN_MASK;
+ 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;
+ ND_ICHECKMSG_U("AVP length", len, <, 6);
/* 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 (len > length) {
+ ND_PRINT(" (len > %u)", length);
+ goto invalid;
+ }
/* If it goes past the end of the remaining length of the captured
data, we'll give up. */
- TCHECK2(*ptr, len);
- /* After this point, no need to worry about truncation */
+ ND_TCHECK_LEN(dat, len);
- if (EXTRACT_16BITS(ptr) & L2TP_AVP_HDR_FLAG_MANDATORY) {
- printf("*");
+ /*
+ * 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 (EXTRACT_16BITS(ptr) & L2TP_AVP_HDR_FLAG_HIDDEN) {
+ if (GET_BE_U_2(dat) & L2TP_AVP_HDR_FLAG_HIDDEN) {
hidden = TRUE;
- printf("?");
+ ND_PRINT("?");
}
- ptr++;
+ dat += 2;
- if (EXTRACT_16BITS(ptr)) {
+ if (GET_BE_U_2(dat)) {
/* Vendor Specific Attribute */
- printf("VENDOR%04x:", EXTRACT_16BITS(ptr)); ptr++;
- printf("ATTR%04x", EXTRACT_16BITS(ptr)); ptr++;
- printf("(");
- print_octets((u_char *)ptr, len-6);
- printf(")");
+ 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 */
- ptr++;
- attr_type = EXTRACT_16BITS(ptr); ptr++;
- printf("%s", tok2str(l2tp_avp2str, "AVP-#%u", attr_type));
- printf("(");
+ 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) {
- printf("???");
+ ND_PRINT("???");
} else {
switch (attr_type) {
case L2TP_AVP_MSGTYPE:
- l2tp_msgtype_print((u_char *)ptr);
+ l2tp_msgtype_print(ndo, dat, len-6);
break;
case L2TP_AVP_RESULT_CODE:
- l2tp_result_code_print((u_char *)ptr, len-6);
+ l2tp_result_code_print(ndo, dat, len-6);
break;
case L2TP_AVP_PROTO_VER:
- l2tp_proto_ver_print(ptr);
+ l2tp_proto_ver_print(ndo, dat, len-6);
break;
case L2TP_AVP_FRAMING_CAP:
- l2tp_framing_cap_print((u_char *)ptr);
+ l2tp_framing_cap_print(ndo, dat, len-6);
break;
case L2TP_AVP_BEARER_CAP:
- l2tp_bearer_cap_print((u_char *)ptr);
+ l2tp_bearer_cap_print(ndo, dat, len-6);
break;
case L2TP_AVP_TIE_BREAKER:
- print_octets((u_char *)ptr, 8);
+ 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:
- print_16bits_val(ptr);
+ 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_SUB_ADDRESS:
case L2TP_AVP_PROXY_AUTH_NAME:
case L2TP_AVP_PRIVATE_GRP_ID:
- print_string((u_char *)ptr, len-6);
+ nd_printjn(ndo, dat, len-6);
break;
case L2TP_AVP_CHALLENGE:
case L2TP_AVP_INI_RECV_LCP:
case L2TP_AVP_PROXY_AUTH_CHAL:
case L2TP_AVP_PROXY_AUTH_RESP:
case L2TP_AVP_RANDOM_VECTOR:
- print_octets((u_char *)ptr, len-6);
+ print_octets(ndo, dat, len-6);
break;
case L2TP_AVP_Q931_CC:
- l2tp_q931_cc_print((u_char *)ptr, len-6);
+ l2tp_q931_cc_print(ndo, dat, len-6);
break;
case L2TP_AVP_CHALLENGE_RESP:
- print_octets((u_char *)ptr, 16);
+ 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_TX_CONN_SPEED:
case L2TP_AVP_PHY_CHANNEL_ID:
case L2TP_AVP_RX_CONN_SPEED:
- print_32bits_val((u_int32_t *)ptr);
+ 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((u_char *)ptr);
+ l2tp_bearer_type_print(ndo, dat, len-6);
break;
case L2TP_AVP_FRAMING_TYPE:
- l2tp_framing_type_print((u_char *)ptr);
+ l2tp_framing_type_print(ndo, dat, len-6);
break;
case L2TP_AVP_PACKET_PROC_DELAY:
- l2tp_packet_proc_delay_print();
+ l2tp_packet_proc_delay_print(ndo);
break;
case L2TP_AVP_PROXY_AUTH_TYPE:
- l2tp_proxy_auth_type_print((u_char *)ptr);
+ l2tp_proxy_auth_type_print(ndo, dat, len-6);
break;
case L2TP_AVP_PROXY_AUTH_ID:
- l2tp_proxy_auth_id_print((u_char *)ptr);
+ l2tp_proxy_auth_id_print(ndo, dat, len-6);
break;
case L2TP_AVP_CALL_ERRORS:
- l2tp_call_errors_print((u_char *)ptr);
+ l2tp_call_errors_print(ndo, dat, len-6);
break;
case L2TP_AVP_ACCM:
- l2tp_accm_print((u_char *)ptr);
+ 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((u_char *)ptr, len-6);
+ l2tp_ppp_discon_cc_print(ndo, dat, len-6);
break;
default:
break;
}
}
- printf(")");
+ ND_PRINT(")");
}
- l2tp_avp_print(dat+len, length-len);
- return;
+ return (len);
- trunc:
- printf("|...");
+invalid:
+ return (0);
}
void
-l2tp_print(const u_char *dat, u_int length)
+l2tp_print(netdissect_options *ndo, const u_char *dat, u_int length)
{
const u_char *ptr = dat;
u_int cnt = 0; /* total octets consumed */
- u_int16_t pad;
+ uint16_t pad;
int flag_t, flag_l, flag_s, flag_o;
- u_int16_t l2tp_len;
+ uint16_t l2tp_len;
+ ndo->ndo_protocol = "l2tp";
flag_t = flag_l = flag_s = flag_o = FALSE;
- TCHECK2(*ptr, 2); /* Flags & Version */
- if ((EXTRACT_16BITS(ptr) & L2TP_VERSION_MASK) == L2TP_VERSION_L2TP) {
- printf(" l2tp:");
- } else if ((EXTRACT_16BITS(ptr) & L2TP_VERSION_MASK) == L2TP_VERSION_L2F) {
- printf(" l2f:");
+ 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 {
- printf(" Unknown Version, neither L2F(1) nor L2TP(2)");
+ ND_PRINT(" Unknown Version, neither L2F(1) nor L2TP(2)");
return; /* nothing we can do */
}
- printf("[");
- if (EXTRACT_16BITS(ptr) & L2TP_FLAG_TYPE) {
+ ND_PRINT("[");
+ if (GET_BE_U_2(ptr) & L2TP_FLAG_TYPE) {
flag_t = TRUE;
- printf("T");
+ ND_PRINT("T");
}
- if (EXTRACT_16BITS(ptr) & L2TP_FLAG_LENGTH) {
+ if (GET_BE_U_2(ptr) & L2TP_FLAG_LENGTH) {
flag_l = TRUE;
- printf("L");
+ ND_PRINT("L");
}
- if (EXTRACT_16BITS(ptr) & L2TP_FLAG_SEQUENCE) {
+ if (GET_BE_U_2(ptr) & L2TP_FLAG_SEQUENCE) {
flag_s = TRUE;
- printf("S");
+ ND_PRINT("S");
}
- if (EXTRACT_16BITS(ptr) & L2TP_FLAG_OFFSET) {
+ if (GET_BE_U_2(ptr) & L2TP_FLAG_OFFSET) {
flag_o = TRUE;
- printf("O");
+ ND_PRINT("O");
}
- if (EXTRACT_16BITS(ptr) & L2TP_FLAG_PRIORITY)
- printf("P");
- printf("]");
+ if (GET_BE_U_2(ptr) & L2TP_FLAG_PRIORITY)
+ ND_PRINT("P");
+ ND_PRINT("]");
ptr += 2;
cnt += 2;
if (flag_l) {
- TCHECK2(*ptr, 2); /* Length */
- l2tp_len = EXTRACT_16BITS(ptr);
+ l2tp_len = GET_BE_U_2(ptr);
ptr += 2;
cnt += 2;
} else {
l2tp_len = 0;
}
-
- TCHECK2(*ptr, 2); /* Tunnel ID */
- printf("(%u/", EXTRACT_16BITS(ptr));
+ /* Tunnel ID */
+ ND_PRINT("(%u/", GET_BE_U_2(ptr));
ptr += 2;
cnt += 2;
- TCHECK2(*ptr, 2); /* Session ID */
- printf("%u)", EXTRACT_16BITS(ptr));
+ /* Session ID */
+ ND_PRINT("%u)", GET_BE_U_2(ptr));
ptr += 2;
cnt += 2;
if (flag_s) {
- TCHECK2(*ptr, 2); /* Ns */
- printf("Ns=%u,", EXTRACT_16BITS(ptr));
+ ND_PRINT("Ns=%u,", GET_BE_U_2(ptr));
ptr += 2;
cnt += 2;
- TCHECK2(*ptr, 2); /* Nr */
- printf("Nr=%u", EXTRACT_16BITS(ptr));
+ ND_PRINT("Nr=%u", GET_BE_U_2(ptr));
ptr += 2;
cnt += 2;
}
- if (flag_o) {
- TCHECK2(*ptr, 2); /* Offset Size */
- pad = EXTRACT_16BITS(ptr);
+ 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) {
- printf(" Length %u larger than packet", l2tp_len);
- return;
+ ND_PRINT(" Length %u larger than packet", l2tp_len);
+ goto invalid;
}
length = l2tp_len;
}
if (length < cnt) {
- printf(" Length %u smaller than header length", length);
- return;
+ ND_PRINT(" Length %u smaller than header length", length);
+ goto invalid;
}
if (flag_t) {
if (!flag_l) {
- printf(" No length");
- return;
+ ND_PRINT(" No length");
+ goto invalid;
}
if (length - cnt == 0) {
- printf(" ZLB");
+ ND_PRINT(" ZLB");
} else {
- l2tp_avp_print(ptr, length - cnt);
+ /*
+ * Print AVPs.
+ */
+ while (length - cnt != 0) {
+ u_int avp_length;
+
+ avp_length = l2tp_avp_print(ndo, ptr, length - cnt);
+ if (avp_length == 0) {
+ goto invalid;
+ }
+ cnt += avp_length;
+ ptr += avp_length;
+ }
}
} else {
- printf(" {");
- ppp_print(ptr, length - cnt);
- printf("}");
+ ND_PRINT(" {");
+ ppp_print(ndo, ptr, length - cnt);
+ ND_PRINT("}");
}
-
return;
-
- trunc:
- printf("%s", tstr);
+invalid:
+ nd_print_invalid(ndo);
}
projects / tcpdump / blobdiff