/* packet-hsrp.c * Routines for the Cisco Hot Standby Router Protocol (HSRP) * * Heikki Vatiainen * * Wireshark - Network traffic analyzer * By Gerald Combs * 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 #include #include void proto_register_hsrp(void); void proto_reg_handoff_hsrp(void); static dissector_handle_t hsrp_handle; static int proto_hsrp; static int hf_hsrp_version; static int hf_hsrp_opcode; /* Opcode 0-2 */ static int hf_hsrp_state; static int hf_hsrp_hellotime; static int hf_hsrp_holdtime; static int hf_hsrp_priority; static int hf_hsrp_group; static int hf_hsrp_reserved; static int hf_hsrp_auth_data; static int hf_hsrp_virt_ip_addr; /* Advertise (3) */ static int hf_hsrp_adv_type; static int hf_hsrp_adv_length; static int hf_hsrp_adv_state; static int hf_hsrp_adv_reserved1; static int hf_hsrp_adv_activegrp; static int hf_hsrp_adv_passivegrp; static int hf_hsrp_adv_reserved2; static int ett_hsrp; /* HSRPv2 */ static int hf_hsrp2_version; static int hf_hsrp2_opcode; static int hf_hsrp2_state; static int hf_hsrp2_group_state_tlv; static int hf_hsrp2_interface_state_tlv; static int hf_hsrp2_text_auth_tlv; static int hf_hsrp2_md5_auth_tlv; static int hf_hsrp2_ipversion; static int hf_hsrp2_hellotime; static int hf_hsrp2_holdtime; static int hf_hsrp2_priority; static int hf_hsrp2_identifier; static int hf_hsrp2_group; static int hf_hsrp2_virt_ip_addr; static int hf_hsrp2_virt_ip_addr_v6; static int hf_hsrp2_auth_data; static int hf_hsrp2_active_group; static int hf_hsrp2_passive_group; static int hf_hsrp2_md5_algorithm; static int hf_hsrp2_md5_padding; static int hf_hsrp2_md5_flags; static int hf_hsrp2_md5_ip_address; static int hf_hsrp2_md5_key_id; static int hf_hsrp2_md5_auth_data; static int ett_hsrp2_group_state_tlv; static int ett_hsrp2_interface_state_tlv; static int ett_hsrp2_text_auth_tlv; static int ett_hsrp2_md5_auth_tlv; static expert_field ei_hsrp_unknown_tlv; #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 */ uint8_t version; /* RFC2281 describes version 0 */ uint8_t opcode; uint8_t state; #define HSRP_DEFAULT_HELLOTIME 3 uint8_t hellotime; /* In seconds */ #define HSRP_DEFAULT_HOLDTIME 10 uint8_t holdtime; /* In seconds */ uint8_t priority; /* Higher is stronger, highest IP address tie-breaker */ uint8_t group; /* Identifies the standby group */ uint8_t reserved; uint8_t auth_data[8]; /* Clear-text password, recommended default is `cisco' */ uint32_t 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 */ uint8_t version; uint8_t opcode; uint8_t state; #define HSRP2_DEFAULT_HELLOTIME 3000 uint32_t hellotime; /* In msecs */ #define HSRP2_DEFAULT_HOLDTIME 10000 uint32_t holdtime; /* In msecs */ uint32_t priority; /* Higher is stronger, highest IP address tie-breaker */ uint16_t group; /* Identifies the standby group */ uint8_t identifier[6]; /* Identifier of sender's MAC address */ uint8_t auth_data[8]; /* Clear-text password, recommended default is `cisco' */ char virt_ip_addr[16]; /* The virtual IPv4/IPv6 address used by this group */ uint8_t md5_algorithm; /* MD5 Hash algorithm */ uint8_t md5_flags; /* Undefined */ uint8_t md5_ip_address; /* IP address of sender interface */ uint8_t md5_key_id; /* Name of key chain */ uint8_t 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, unsigned offset) { uint8_t type = tvb_get_uint8(tvb, offset); uint8_t len = tvb_get_uint8(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; uint32_t 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 */ uint8_t opcode, state = 0; proto_item *ti; proto_tree *hsrp_tree; int offset; uint8_t hellotime, holdtime; char *auth; col_set_str(pinfo->cinfo, COL_PROTOCOL, "HSRP"); opcode = tvb_get_uint8(tvb, 1); col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(opcode, hsrp_opcode_vals, "Unknown")); if (opcode < 3) { state = tvb_get_uint8(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_uint8(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_uint8(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_uint8(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 = (char *) 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 */ unsigned offset2 = offset + 4; /* this now points to the start of a possible TLV sequence */ uint8_t type = tvb_get_uint8(tvb, offset2); uint8_t len = tvb_get_uint8(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 */ unsigned offset = 0, offset2; proto_item *ti = NULL; proto_tree *hsrp_tree = NULL; uint8_t 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_uint8(tvb, offset); len = tvb_get_uint8(tvb, offset+1); offset2 = offset; if (type == 1 && len == 40) { /* Group State TLV */ uint8_t opcode, state = 0, ipver; uint32_t 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_uint8(tvb, offset+1); col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(opcode, hsrp2_opcode_vals, "Unknown")); state = tvb_get_uint8(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_uint8(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 */ uint16_t 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; char *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 = (char *) 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 int *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: */