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|
/* packet-hsrp.c
* Routines for the Cisco Hot Standby Router Protocol (HSRP)
*
* Heikki Vatiainen <hessu@cs.tut.fi>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* Copied from packet-vrrp.c
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
/*
* RFC 2281 describes opcodes 0 - 2
*
* Op Code 3: **** HSRP Interface State Advertisements ****
* http://www.cisco.com/en/US/products/sw/iosswrel/ps1834/products_feature_guide09186a00800e9763.html
*
* An HSRP interface-state advertisement is sent:
*
* * when HSRP on the interface enters or leaves the passive state
* * when a group on the interface learns a new Active router
* * periodically while the interface is in the passive state
*
* 1 2 3
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Version | Op Code = 3 | TLV Type |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | TLV Length | State | Reserved |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Active Group Count | Passive Group Count |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Reserved |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* Passive Group Count: 2 octet
*
* A count of the number of passive groups on the interface. The range
* of values are 0-256.
*
* Active Group Count: 2 octet
*
* A count of the number of active groups on the interface. The range
* of values are 0-256.
*
*
* HSRP Version 2
* Ref. http://www.smartnetworks.jp/2006/02/hsrp_8_hsrp_version_2.html (Japanese Only)
*
* Group State TLV
*
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type=1 | Length=40 | HSRP Version | Opcode |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | State | IP Version | Group Number |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Identifier(6octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Identifier | Priority(4octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Priority cont. | Hello Time(4octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Hello Time cont. | Hold Time(4octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Hold Time cont. | Virtual IP Address(16octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Virtual IP Address cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Virtual IP Address cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Virtual IP Address cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Virtual IP Address cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* Interface State TLV
*
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type=2 | Length=4 | Active Groups |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Passive Groups |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* Text Authentication TLV
*
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type=3 | Length=8 | Authentication Data(8octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* MD5 Authentication TLV
*
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type=4 | Length | Algorithm | Padding |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Flags | IP Address(4octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | IP Address cont. | Key ID(4octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Key ID cont. | Authentication Data(16octets) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data cont. |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
*/
#include "config.h"
#include <epan/packet.h>
#include <epan/to_str.h>
#include <epan/expert.h>
void proto_register_hsrp(void);
void proto_reg_handoff_hsrp(void);
static dissector_handle_t hsrp_handle;
static gint proto_hsrp = -1;
static gint hf_hsrp_version = -1;
static gint hf_hsrp_opcode = -1;
/* Opcode 0-2 */
static gint hf_hsrp_state = -1;
static gint hf_hsrp_hellotime = -1;
static gint hf_hsrp_holdtime = -1;
static gint hf_hsrp_priority = -1;
static gint hf_hsrp_group = -1;
static gint hf_hsrp_reserved = -1;
static gint hf_hsrp_auth_data = -1;
static gint hf_hsrp_virt_ip_addr = -1;
/* Advertise (3) */
static gint hf_hsrp_adv_type = -1;
static gint hf_hsrp_adv_length = -1;
static gint hf_hsrp_adv_state = -1;
static gint hf_hsrp_adv_reserved1 = -1;
static gint hf_hsrp_adv_activegrp = -1;
static gint hf_hsrp_adv_passivegrp = -1;
static gint hf_hsrp_adv_reserved2 = -1;
static gint ett_hsrp = -1;
/* HSRPv2 */
static gint hf_hsrp2_version = -1;
static gint hf_hsrp2_opcode = -1;
static gint hf_hsrp2_state = -1;
static gint hf_hsrp2_group_state_tlv = -1;
static gint hf_hsrp2_interface_state_tlv = -1;
static gint hf_hsrp2_text_auth_tlv = -1;
static gint hf_hsrp2_md5_auth_tlv = -1;
static gint hf_hsrp2_ipversion = -1;
static gint hf_hsrp2_hellotime = -1;
static gint hf_hsrp2_holdtime = -1;
static gint hf_hsrp2_priority = -1;
static gint hf_hsrp2_identifier = -1;
static gint hf_hsrp2_group = -1;
static gint hf_hsrp2_virt_ip_addr = -1;
static gint hf_hsrp2_virt_ip_addr_v6 = -1;
static gint hf_hsrp2_auth_data = -1;
static gint hf_hsrp2_active_group = -1;
static gint hf_hsrp2_passive_group = -1;
static gint hf_hsrp2_md5_algorithm = -1;
static gint hf_hsrp2_md5_padding = -1;
static gint hf_hsrp2_md5_flags = -1;
static gint hf_hsrp2_md5_ip_address= -1;
static gint hf_hsrp2_md5_key_id= -1;
static gint hf_hsrp2_md5_auth_data= -1;
static gint ett_hsrp2_group_state_tlv = -1;
static gint ett_hsrp2_interface_state_tlv = -1;
static gint ett_hsrp2_text_auth_tlv = -1;
static gint ett_hsrp2_md5_auth_tlv = -1;
static expert_field ei_hsrp_unknown_tlv = EI_INIT;
#define UDP_PORT_HSRP 1985
#define UDP_PORT_HSRP2_V6 2029
#define UDP_PORT_HSRP_RANGE "1985,2029"
#define HSRP_DST_IP_ADDR 0xE0000002
#define HSRP2_DST_IP_ADDR 0xE0000066
struct hsrp_packet { /* Multicast to 224.0.0.2, TTL 1, UDP, port 1985 */
guint8 version; /* RFC2281 describes version 0 */
guint8 opcode;
guint8 state;
#define HSRP_DEFAULT_HELLOTIME 3
guint8 hellotime; /* In seconds */
#define HSRP_DEFAULT_HOLDTIME 10
guint8 holdtime; /* In seconds */
guint8 priority; /* Higher is stronger, highest IP address tie-breaker */
guint8 group; /* Identifies the standby group */
guint8 reserved;
guint8 auth_data[8]; /* Clear-text password, recommended default is `cisco' */
guint32 virt_ip_addr; /* The virtual IP address used by this group */
};
struct hsrpv2_packet { /* Multicast to 224.0.0.102, TTL 1, UDP, port 1985 */
guint8 version;
guint8 opcode;
guint8 state;
#define HSRP2_DEFAULT_HELLOTIME 3000
guint32 hellotime; /* In msecs */
#define HSRP2_DEFAULT_HOLDTIME 10000
guint32 holdtime; /* In msecs */
guint32 priority; /* Higher is stronger, highest IP address tie-breaker */
guint16 group; /* Identifies the standby group */
guint8 identifier[6]; /* Identifier of sender's MAC address */
guint8 auth_data[8]; /* Clear-text password, recommended default is `cisco' */
gchar virt_ip_addr[16]; /* The virtual IPv4/IPv6 address used by this group */
guint8 md5_algorithm; /* MD5 Hash algorithm */
guint8 md5_flags; /* Undefined */
guint8 md5_ip_address; /* IP address of sender interface */
guint8 md5_key_id; /* Name of key chain */
guint8 md5_auth_data[16]; /* MD5 digest data */
};
#define HSRP_OPCODE_HELLO 0
#define HSRP_OPCODE_COUP 1
#define HSRP_OPCODE_RESIGN 2
#define HSRP_OPCODE_ADVERTISE 3
static const value_string hsrp_opcode_vals[] = {
{HSRP_OPCODE_HELLO, "Hello"},
{HSRP_OPCODE_COUP, "Coup"},
{HSRP_OPCODE_RESIGN, "Resign"},
{HSRP_OPCODE_ADVERTISE, "Advertise"},
{0, NULL}
};
#define HSRP_STATE_INITIAL 0
#define HSRP_STATE_LEARN 1
#define HSRP_STATE_LISTEN 2
#define HSRP_STATE_SPEAK 4
#define HSRP_STATE_STANDBY 8
#define HSRP_STATE_ACTIVE 16
static const value_string hsrp_state_vals[] = {
{HSRP_STATE_INITIAL, "Initial"},
{HSRP_STATE_LEARN, "Learn"},
{HSRP_STATE_LISTEN, "Listen"},
{HSRP_STATE_SPEAK, "Speak"},
{HSRP_STATE_STANDBY, "Standby"},
{HSRP_STATE_ACTIVE, "Active"},
{0, NULL}
};
#define HSRP_ADV_TYPE_INTSTATE 1
#define HSRP_ADV_TYPE_IPREDUN 2
static const value_string hsrp_adv_type_vals[] = {
{HSRP_ADV_TYPE_INTSTATE, "HSRP interface state"},
{HSRP_ADV_TYPE_IPREDUN, "IP redundancy"},
{0, NULL}
};
#define HSRP_ADV_STATE_DORMANT 1
#define HSRP_ADV_STATE_PASSIVE 2
#define HSRP_ADV_STATE_ACTIVE 3
static const value_string hsrp_adv_state_vals[] = {
{HSRP_ADV_STATE_DORMANT, "Dormant"},
{HSRP_ADV_STATE_PASSIVE, "Passive"},
{HSRP_ADV_STATE_ACTIVE, "Active"},
{0, NULL}
};
#define HSRP2_OPCODE_HELLO 0
#define HSRP2_OPCODE_COUP 1
#define HSRP2_OPCODE_RESIGN 2
static const value_string hsrp2_opcode_vals[] = {
{HSRP2_OPCODE_HELLO, "Hello"},
{HSRP2_OPCODE_COUP, "Coup"},
{HSRP2_OPCODE_RESIGN, "Resign"},
{0, NULL}
};
#define HSRP2_STATE_DISABLED 0
#define HSRP2_STATE_INIT 1
#define HSRP2_STATE_LEARN 2
#define HSRP2_STATE_LISTEN 3
#define HSRP2_STATE_SPEAK 4
#define HSRP2_STATE_STANDBY 5
#define HSRP2_STATE_ACTIVE 6
static const value_string hsrp2_state_vals[] = {
{HSRP2_STATE_INIT, "Init"},
{HSRP2_STATE_LEARN, "Learn"},
{HSRP2_STATE_LISTEN, "Listen"},
{HSRP2_STATE_SPEAK, "Speak"},
{HSRP2_STATE_STANDBY, "Standby"},
{HSRP2_STATE_ACTIVE, "Active"},
{0, NULL}
};
#define HSRP2_IPVERSION_IPV4 4
#define HSRP2_IPVERSION_IPV6 6
static const value_string hsrp2_ipversion_vals[] = {
{HSRP2_IPVERSION_IPV4, "IPv4"},
{HSRP2_IPVERSION_IPV6, "IPv6"},
{0, NULL}
};
#define HSRP2_MD5_ALGORITHM 1
static const value_string hsrp2_md5_algorithm_vals[] = {
{HSRP2_MD5_ALGORITHM, "MD5"},
{0, NULL}
};
static void
process_hsrp_md5_tlv_sequence(tvbuff_t *tvb, proto_tree *hsrp_tree, guint offset)
{
guint8 type = tvb_get_guint8(tvb, offset);
guint8 len = tvb_get_guint8(tvb, offset+1);
proto_item *ti;
proto_tree *md5_auth_tlv;
ti = proto_tree_add_uint_format_value(hsrp_tree, hf_hsrp2_md5_auth_tlv, tvb, offset, 1, type, "Type=%d Len=%d", type, len);
offset+=2;
/* Making MD5 Authentication TLV subtree */
md5_auth_tlv = proto_item_add_subtree(ti, ett_hsrp2_md5_auth_tlv);
proto_tree_add_item(md5_auth_tlv, hf_hsrp2_md5_algorithm, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
/* padding field */
proto_tree_add_item(md5_auth_tlv, hf_hsrp2_md5_padding, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(md5_auth_tlv, hf_hsrp2_md5_flags, tvb, offset, 2, ENC_BIG_ENDIAN);
offset+=2;
proto_tree_add_item(md5_auth_tlv, hf_hsrp2_md5_ip_address, tvb, offset, 4, ENC_BIG_ENDIAN);
offset+=4;
proto_tree_add_item(md5_auth_tlv, hf_hsrp2_md5_key_id, tvb, offset, 4, ENC_BIG_ENDIAN);
offset+=4; /* this now points to the start of the MD5 hash */
proto_tree_add_item(md5_auth_tlv, hf_hsrp2_md5_auth_data, tvb, offset, 16, ENC_NA);
}
static int
dissect_hsrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
tvbuff_t *next_tvb;
guint32 hsrpv1 = g_htonl(HSRP_DST_IP_ADDR),
hsrpv2 = g_htonl(HSRP2_DST_IP_ADDR);
/* Return if this isn't really HSRP traffic
* (source and destination port must be UDP_PORT_HSRP on HSRPv1 or HSRPv2(IPv4))
* (source and destination port must be UDP_PORT_HSRP2_V6 on HSRPv2(IPv6))
*/
if(pinfo->destport != UDP_PORT_HSRP && pinfo->destport != UDP_PORT_HSRP2_V6)
return 0;
/*
* To check whether this is an HSRPv1 packet or HSRPv2 on dest IPv4 addr.
*/
if (pinfo->dst.type == AT_IPv4 && memcmp(pinfo->dst.data, &hsrpv1, 4) == 0) {
/* HSRPv1 */
guint8 opcode, state = 0;
proto_item *ti;
proto_tree *hsrp_tree;
gint offset;
guint8 hellotime, holdtime;
gchar *auth;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "HSRP");
opcode = tvb_get_guint8(tvb, 1);
col_set_str(pinfo->cinfo, COL_INFO,
val_to_str_const(opcode, hsrp_opcode_vals, "Unknown"));
if (opcode < 3) {
state = tvb_get_guint8(tvb, 2);
col_append_fstr(pinfo->cinfo, COL_INFO, " (state %s)",
val_to_str_const(state, hsrp_state_vals, "Unknown"));
} else if (opcode == 3) {
state = tvb_get_guint8(tvb, 6);
col_append_fstr(pinfo->cinfo, COL_INFO, " (state %s)",
val_to_str_const(state, hsrp_adv_state_vals, "Unknown"));
}
offset = 0;
ti = proto_tree_add_item(tree, proto_hsrp, tvb, offset, -1, ENC_NA);
hsrp_tree = proto_item_add_subtree(ti, ett_hsrp);
proto_tree_add_item(hsrp_tree, hf_hsrp_version, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_uint(hsrp_tree, hf_hsrp_opcode, tvb, offset, 1, opcode);
offset++;
if (opcode < 3) {
proto_tree_add_uint(hsrp_tree, hf_hsrp_state, tvb, offset, 1, state);
offset++;
hellotime = tvb_get_guint8(tvb, offset);
proto_tree_add_uint_format_value(hsrp_tree, hf_hsrp_hellotime, tvb, offset, 1, hellotime,
"%sDefault (%u)",
(hellotime == HSRP_DEFAULT_HELLOTIME) ? "" : "Non-",
hellotime);
offset++;
holdtime = tvb_get_guint8(tvb, offset);
proto_tree_add_uint_format_value(hsrp_tree, hf_hsrp_holdtime, tvb, offset, 1, holdtime,
"%sDefault (%u)",
(holdtime == HSRP_DEFAULT_HOLDTIME) ? "" : "Non-",
holdtime);
offset++;
proto_tree_add_item(hsrp_tree, hf_hsrp_priority, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(hsrp_tree, hf_hsrp_group, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(hsrp_tree, hf_hsrp_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
auth = (gchar *) tvb_get_string_enc(pinfo->pool, tvb, offset, 8, ENC_ASCII|ENC_NA);
proto_tree_add_string_format_value(hsrp_tree, hf_hsrp_auth_data, tvb, offset, 8, auth,
"%sDefault (%s)",
(strcmp(auth, "cisco") == 0) ? "" : "Non-",
auth);
offset += 8;
proto_tree_add_item(hsrp_tree, hf_hsrp_virt_ip_addr, tvb, offset, 4, ENC_BIG_ENDIAN);
/* offset += 4; */
} else if (opcode == 3) {
proto_tree_add_item(hsrp_tree, hf_hsrp_adv_type, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(hsrp_tree, hf_hsrp_adv_length, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(hsrp_tree, hf_hsrp_adv_state, tvb, offset, 1, ENC_BIG_ENDIAN);
offset += 1;
proto_tree_add_item(hsrp_tree, hf_hsrp_adv_reserved1, tvb, offset, 1, ENC_BIG_ENDIAN);
offset += 1;
proto_tree_add_item(hsrp_tree, hf_hsrp_adv_activegrp, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(hsrp_tree, hf_hsrp_adv_passivegrp, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(hsrp_tree, hf_hsrp_adv_reserved2, tvb, offset, 4, ENC_BIG_ENDIAN);
/* offset += 4; */
} else {
next_tvb = tvb_new_subset_remaining(tvb, offset);
call_data_dissector(next_tvb, pinfo, hsrp_tree);
}
/* is MD5 authentication being used with HSRPv1? */
if (tvb_captured_length(tvb) == 50) { /* 20 bytes of regular HSRP data + 30 bytes of authentication payload */
guint offset2 = offset + 4; /* this now points to the start of a possible TLV sequence */
guint8 type = tvb_get_guint8(tvb, offset2);
guint8 len = tvb_get_guint8(tvb, offset2+1);
if (type == 4 && len == 28) {
/* MD5 Authentication TLV */
if (tree) {
process_hsrp_md5_tlv_sequence(tvb, hsrp_tree, offset2);
}
} else {
expert_add_info_format(pinfo, ti, &ei_hsrp_unknown_tlv,
"Unknown TLV sequence in HSRPv1 dissection, Type=(%d) Len=(%d)", type, len);
}
}
} else if ((pinfo->dst.type == AT_IPv4 && memcmp(pinfo->dst.data, &hsrpv2, 4) == 0) ||
(pinfo->dst.type == AT_IPv6 && pinfo->destport == UDP_PORT_HSRP2_V6)) {
/* HSRPv2 */
guint offset = 0, offset2;
proto_item *ti = NULL;
proto_tree *hsrp_tree = NULL;
guint8 type,len;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "HSRPv2");
if (tree) {
ti = proto_tree_add_item(tree, proto_hsrp, tvb, offset, -1, ENC_NA);
hsrp_tree = proto_item_add_subtree(ti, ett_hsrp);
}
while (tvb_reported_length_remaining(tvb, offset) > 0) {
type = tvb_get_guint8(tvb, offset);
len = tvb_get_guint8(tvb, offset+1);
offset2 = offset;
if (type == 1 && len == 40) {
/* Group State TLV */
guint8 opcode, state = 0, ipver;
guint32 hellotime, holdtime;
proto_tree *group_state_tlv;
if (tree) {
ti = proto_tree_add_uint_format_value(hsrp_tree, hf_hsrp2_group_state_tlv, tvb, offset, 2+len, type,
"Type=%d Len=%d", type, len);
}
offset+=2;
opcode = tvb_get_guint8(tvb, offset+1);
col_add_fstr(pinfo->cinfo, COL_INFO, "%s",
val_to_str_const(opcode, hsrp2_opcode_vals, "Unknown"));
state = tvb_get_guint8(tvb, offset+2);
col_append_fstr(pinfo->cinfo, COL_INFO, " (state %s)",
val_to_str_const(state, hsrp2_state_vals, "Unknown"));
if (tree) {
/* Making Group State TLV subtree. */
group_state_tlv = proto_item_add_subtree(ti, ett_hsrp2_group_state_tlv);
proto_tree_add_item(group_state_tlv, hf_hsrp2_version, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_uint(group_state_tlv, hf_hsrp2_opcode, tvb, offset, 1, opcode);
offset++;
proto_tree_add_uint(group_state_tlv, hf_hsrp2_state, tvb, offset, 1, state);
offset++;
ipver = tvb_get_guint8(tvb, offset);
proto_tree_add_uint(group_state_tlv, hf_hsrp2_ipversion, tvb, offset, 1, ipver);
offset++;
proto_tree_add_item(group_state_tlv, hf_hsrp2_group, tvb, offset, 2, ENC_BIG_ENDIAN);
offset+=2;
proto_tree_add_item(group_state_tlv, hf_hsrp2_identifier, tvb, offset, 6, ENC_NA);
offset+=6;
proto_tree_add_item(group_state_tlv, hf_hsrp2_priority, tvb, offset, 4, ENC_BIG_ENDIAN);
offset+=4;
hellotime = tvb_get_ntohl(tvb, offset);
proto_tree_add_uint_format_value(group_state_tlv, hf_hsrp2_hellotime, tvb, offset, 4, hellotime,
"%sDefault (%u)",
(hellotime == HSRP2_DEFAULT_HELLOTIME) ? "" : "Non-",
hellotime);
offset+=4;
holdtime = tvb_get_ntohl(tvb, offset);
proto_tree_add_uint_format_value(group_state_tlv, hf_hsrp2_holdtime, tvb, offset, 4, holdtime,
"%sDefault (%u)",
(holdtime == HSRP2_DEFAULT_HOLDTIME) ? "" : "Non-",
holdtime);
offset+=4;
if (ipver == 4) {
/* Fetch Virtual IP as IPv4 */
proto_tree_add_item(group_state_tlv, hf_hsrp2_virt_ip_addr, tvb, offset, 4, ENC_BIG_ENDIAN);
} else if (ipver == 6) {
/* Fetch Virtual IP as IPv6 */
proto_tree_add_item(group_state_tlv, hf_hsrp2_virt_ip_addr_v6, tvb, offset, 16, ENC_NA);
} else {
/* Unknown protocol */
next_tvb = tvb_new_subset_remaining(tvb, offset);
call_data_dissector(next_tvb, pinfo, hsrp_tree);
break;
}
/* offset+=16; */
}
} else if (type == 2 && len == 4) {
/* Interface State TLV */
guint16 active,passive;
active = tvb_get_ntohs(tvb, offset+2);
passive = tvb_get_ntohs(tvb, offset+4);
col_add_fstr(pinfo->cinfo, COL_INFO, "Interface State TLV (Act=%d Pass=%d)",active,passive);
if (tree) {
proto_tree *interface_state_tlv;
ti = proto_tree_add_uint_format_value(hsrp_tree, hf_hsrp2_interface_state_tlv, tvb, offset, 1, type,
"Type=%d Len=%d", type, 2+len);
offset+=2;
/* Making Interface State TLV subtree */
interface_state_tlv = proto_item_add_subtree(ti, ett_hsrp2_interface_state_tlv);
proto_tree_add_item(interface_state_tlv, hf_hsrp2_active_group, tvb, offset, 2, ENC_BIG_ENDIAN);
offset+=2;
proto_tree_add_item(interface_state_tlv, hf_hsrp2_passive_group, tvb, offset, 2, ENC_BIG_ENDIAN);
/* offset+=2; */
}
} else if (type == 3 && len == 8) {
/* Text Authentication TLV */
/* FIXME: Is the length of the authentication string really restricted to 8 bytes
* or is it maybe padded to multiples of 4 or 8 bytes?
*/
if (tree) {
proto_tree *text_auth_tlv;
gchar *auth;
ti = proto_tree_add_uint_format_value(hsrp_tree, hf_hsrp2_text_auth_tlv, tvb, offset, 2+len, type,
"Type=%d Len=%d", type, len);
offset+=2;
/* Making Text Authentication TLV subtree */
text_auth_tlv = proto_item_add_subtree(ti, ett_hsrp2_text_auth_tlv);
auth = (gchar *) tvb_get_string_enc(pinfo->pool, tvb, offset, 8, ENC_ASCII|ENC_NA);
proto_tree_add_string_format_value(text_auth_tlv, hf_hsrp2_auth_data, tvb, offset, 8, auth,
"%sDefault (%s)",
(strcmp(auth, "cisco") == 0) ? "" : "Non-",
auth);
/* offset += 8; */
}
} else if (type == 4 && len == 28) {
/* MD5 Authentication TLV */
if (tree) {
process_hsrp_md5_tlv_sequence(tvb, hsrp_tree, offset);
/* offset += 16; */
}
} else {
/* Undefined TLV */
next_tvb = tvb_new_subset_remaining(tvb, offset);
call_data_dissector(next_tvb, pinfo, hsrp_tree);
break;
}
offset = offset2+len+2;
}
}
return tvb_captured_length(tvb);
}
void proto_register_hsrp(void)
{
expert_module_t* expert_hsrp;
static hf_register_info hf[] = {
{ &hf_hsrp_version,
{ "Version", "hsrp.version",
FT_UINT8, BASE_DEC, NULL, 0x0,
"The version of the HSRP messages", HFILL }},
{ &hf_hsrp_opcode,
{ "Op Code", "hsrp.opcode",
FT_UINT8, BASE_DEC, VALS(hsrp_opcode_vals), 0x0,
"The type of message contained in this packet", HFILL }},
{ &hf_hsrp_state,
{ "State", "hsrp.state",
FT_UINT8, BASE_DEC, VALS(hsrp_state_vals), 0x0,
"The current state of the router sending the message", HFILL }},
{ &hf_hsrp_hellotime,
{ "Hellotime", "hsrp.hellotime",
FT_UINT8, BASE_DEC, NULL, 0x0,
"The approximate period between the Hello messages that the router sends", HFILL }},
{ &hf_hsrp_holdtime,
{ "Holdtime", "hsrp.holdtime",
FT_UINT8, BASE_DEC, NULL, 0x0,
"Time that the current Hello message should be considered valid", HFILL }},
{ &hf_hsrp_priority,
{ "Priority", "hsrp.priority",
FT_UINT8, BASE_DEC, NULL, 0x0,
"Used to elect the active and standby routers. Numerically higher priority wins vote", HFILL }},
{ &hf_hsrp_group,
{ "Group", "hsrp.group",
FT_UINT8, BASE_DEC, NULL, 0x0,
"This field identifies the standby group", HFILL }},
{ &hf_hsrp_reserved,
{ "Reserved", "hsrp.reserved",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }},
{ &hf_hsrp_auth_data,
{ "Authentication Data", "hsrp.auth_data",
FT_STRING, BASE_NONE, NULL, 0x0,
"Contains a clear-text 8 character reused password", HFILL }},
{ &hf_hsrp_virt_ip_addr,
{ "Virtual IP Address", "hsrp.virt_ip",
FT_IPv4, BASE_NONE, NULL, 0x0,
"The virtual IP address used by this group", HFILL }},
{ &hf_hsrp_adv_type,
{ "Adv type", "hsrp.adv.tlvtype",
FT_UINT16, BASE_DEC, VALS(hsrp_adv_type_vals), 0x0,
"Advertisement tlv type", HFILL }},
{ &hf_hsrp_adv_length,
{ "Adv length", "hsrp.adv.tlvlength",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Advertisement tlv length", HFILL }},
{ &hf_hsrp_adv_state,
{ "Adv state", "hsrp.adv.state",
FT_UINT8, BASE_DEC, VALS(hsrp_adv_state_vals), 0x0,
"Advertisement tlv length", HFILL }},
{ &hf_hsrp_adv_reserved1,
{ "Adv reserved1", "hsrp.adv.reserved1",
FT_UINT8, BASE_DEC, NULL, 0x0,
"Advertisement tlv length", HFILL }},
{ &hf_hsrp_adv_activegrp,
{ "Adv active groups", "hsrp.adv.activegrp",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Advertisement active group count", HFILL }},
{ &hf_hsrp_adv_passivegrp,
{ "Adv passive groups", "hsrp.adv.passivegrp",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Advertisement passive group count", HFILL }},
{ &hf_hsrp_adv_reserved2,
{ "Adv reserved2", "hsrp.adv.reserved2",
FT_UINT32, BASE_DEC, NULL, 0x0,
"Advertisement tlv length", HFILL }},
{ &hf_hsrp2_version,
{ "Version", "hsrp2.version",
FT_UINT8, BASE_DEC, NULL, 0x0,
"The version of the HSRP messages", HFILL }},
{ &hf_hsrp2_opcode,
{ "Op Code", "hsrp2.opcode",
FT_UINT8, BASE_DEC, VALS(hsrp2_opcode_vals), 0x0,
"The type of message contained in this packet", HFILL }},
{ &hf_hsrp2_state,
{ "State", "hsrp2.state",
FT_UINT8, BASE_DEC, VALS(hsrp2_state_vals), 0x0,
"The current state of the router sending the message", HFILL }},
{ &hf_hsrp2_group_state_tlv,
{ "Group State TLV", "hsrp2.group_state_tlv",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }},
{ &hf_hsrp2_interface_state_tlv,
{ "Interface State TLV", "hsrp2.interface_state_tlv",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }},
{ &hf_hsrp2_text_auth_tlv,
{ "Text Authentication TLV", "hsrp2.text_auth_tlv",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }},
{ &hf_hsrp2_md5_auth_tlv,
{ "MD5 Authentication TLV", "hsrp2.md5_auth_tlv",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }},
{ &hf_hsrp2_ipversion,
{ "IP Ver.", "hsrp2.ipversion",
FT_UINT8, BASE_DEC, VALS(hsrp2_ipversion_vals), 0x0,
"The IP protocol version used in this hsrp message", HFILL }},
{ &hf_hsrp2_group,
{ "Group", "hsrp2.group",
FT_UINT16, BASE_DEC, NULL, 0x0,
"This field identifies the standby group", HFILL }},
{ &hf_hsrp2_identifier,
{ "Identifier", "hsrp2.identifier",
FT_ETHER, BASE_NONE, NULL, 0x0,
"BIA value of a sender interface", HFILL }},
{ &hf_hsrp2_hellotime,
{ "Hellotime", "hsrp2.hellotime",
FT_UINT32, BASE_DEC, NULL, 0x0,
"The approximate period between the Hello messages that the router sends", HFILL }},
{ &hf_hsrp2_holdtime,
{ "Holdtime", "hsrp2.holdtime",
FT_UINT32, BASE_DEC, NULL, 0x0,
"Time that the current Hello message should be considered valid", HFILL }},
{ &hf_hsrp2_priority,
{ "Priority", "hsrp2.priority",
FT_UINT32, BASE_DEC, NULL, 0x0,
"Used to elect the active and standby routers. Numerically higher priority wins vote", HFILL }},
{ &hf_hsrp2_auth_data,
{ "Authentication Data", "hsrp2.auth_data",
FT_STRING, BASE_NONE, NULL, 0x0,
"Contains a clear-text 8 character reused password", HFILL }},
{ &hf_hsrp2_virt_ip_addr,
{ "Virtual IP Address", "hsrp2.virt_ip",
FT_IPv4, BASE_NONE, NULL, 0x0,
"The virtual IP address used by this group", HFILL }},
{ &hf_hsrp2_virt_ip_addr_v6,
{ "Virtual IPv6 Address", "hsrp2.virt_ip_v6",
FT_IPv6, BASE_NONE, NULL, 0x0,
"The virtual IPv6 address used by this group", HFILL }},
{ &hf_hsrp2_active_group,
{ "Active Groups", "hsrp2.active_groups",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Active group number which becomes the active router myself", HFILL }},
{ &hf_hsrp2_passive_group,
{ "Passive Groups", "hsrp2.passive_groups",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Standby group number which doesn't become the active router myself", HFILL }},
{ &hf_hsrp2_md5_algorithm,
{ "MD5 Algorithm", "hsrp2.md5_algorithm",
FT_UINT8, BASE_DEC, VALS(hsrp2_md5_algorithm_vals), 0x0,
"Hash Algorithm used by this group", HFILL }},
{ &hf_hsrp2_md5_padding,
{ "Padding", "hsrp2.md5_padding",
FT_UINT8, BASE_HEX, NULL, 0x0,
"Must be zero", HFILL }},
{ &hf_hsrp2_md5_flags,
{ "MD5 Flags", "hsrp2.md5_flags",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Undefined", HFILL }},
{ &hf_hsrp2_md5_ip_address,
{ "Sender's IP Address", "hsrp.md5_ip_address",
FT_IPv4, BASE_NONE, NULL, 0x0,
"IP Address of the sender interface", HFILL }},
{ &hf_hsrp2_md5_key_id,
{ "MD5 Key ID", "hsrp2.md5_key_id",
FT_UINT32, BASE_DEC, NULL, 0x0,
"This field contains Key chain ID", HFILL }},
{ &hf_hsrp2_md5_auth_data,
{ "MD5 Authentication Data", "hsrp2.md5_auth_data",
FT_BYTES, BASE_NONE, NULL, 0x0,
"MD5 digest string is contained.", HFILL }}
};
static gint *ett[] = {
&ett_hsrp,
&ett_hsrp2_group_state_tlv,
&ett_hsrp2_interface_state_tlv,
&ett_hsrp2_text_auth_tlv,
&ett_hsrp2_md5_auth_tlv
};
static ei_register_info ei[] = {
{ &ei_hsrp_unknown_tlv, { "hsrp.unknown_tlv", PI_UNDECODED, PI_WARN, "Unknown TLV sequence (HSRPv1)", EXPFILL }},
};
proto_hsrp = proto_register_protocol("Cisco Hot Standby Router Protocol", "HSRP", "hsrp");
proto_register_field_array(proto_hsrp, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
expert_hsrp = expert_register_protocol(proto_hsrp);
expert_register_field_array(expert_hsrp, ei, array_length(ei));
hsrp_handle = register_dissector("hsrp", dissect_hsrp, proto_hsrp);
}
void
proto_reg_handoff_hsrp(void)
{
dissector_add_uint_range_with_preference("udp.port", UDP_PORT_HSRP_RANGE, hsrp_handle);
}
/*
* Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=8 tabstop=8 expandtab:
* :indentSize=8:tabSize=8:noTabs=true:
*/
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