wireshark/epan/dissectors/packet-mpls-y1711.c

423 lines
16 KiB
C

/* packet-mpls-y1711.c
* Routines for (old) ITU-T MPLS OAM: it conforms to ITU-T Y.1711 and RFC 3429
*
* Copyright 2006, 2011 _FF_
*
* Francesco Fondelli <francesco dot fondelli, gmail dot com>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/*
* FF: NOTES
*
* - this should dissect OAM pdus (identified by the MPLS_LABEL_OAM_ALERT = 14
* label) as described in ITU-T Y.1711 and RFC 3429.
*
* - this code used to be (since 2006) in packet-mpls.c ... nobody on this
* planet is using Y.1711 today (?), so thanks to the mpls subdissector
* table indexed by label value it has been moved here.
*/
#include "config.h"
#include <epan/packet.h>
#include <epan/expert.h>
#include "packet-mpls.h"
void proto_register_mpls_y1711(void);
void proto_reg_handoff_mpls_y1711(void);
static gint proto_mpls_y1711 = -1;
static int hf_mpls_y1711_function_type = -1;
/* static int hf_mpls_y1711_ttsi = -1; */
static int hf_mpls_y1711_frequency = -1;
static int hf_mpls_y1711_defect_type = -1;
static int hf_mpls_y1711_defect_location = -1;
static int hf_mpls_y1711_bip16 = -1;
/* Generated from convert_proto_tree_add_text.pl */
static int hf_mpls_y1711_lsr_id = -1;
static int hf_mpls_y1711_lsp_id = -1;
static gint ett_mpls_y1711 = -1;
/* Generated from convert_proto_tree_add_text.pl */
static expert_field ei_mpls_y1711_padding_not_ff = EI_INIT;
static expert_field ei_mpls_y1711_reserved_not_zero = EI_INIT;
static expert_field ei_mpls_y1711_ttsi_not_preset = EI_INIT;
static expert_field ei_mpls_y1711_minimum_payload = EI_INIT;
static expert_field ei_mpls_y1711_s_bit_not_one = EI_INIT;
static expert_field ei_mpls_y1711_no_OAM_alert_label = EI_INIT;
static expert_field ei_mpls_y1711_exp_bits_not_zero = EI_INIT;
static expert_field ei_mpls_y1711_ttl_not_one = EI_INIT;
static expert_field ei_mpls_y1711_padding_not_zero = EI_INIT;
static expert_field ei_mpls_y1711_unknown_pdu = EI_INIT;
static dissector_handle_t mpls_y1711_handle;
static const value_string y1711_function_type_vals[] = {
{0x00, "Reserved" },
{0x01, "CV (Connectivity Verification)" },
{0x02, "FDI (Forward Defect Indicator)" },
{0x03, "BDI (Backward Defect Indicator)" },
{0x04, "Reserved for Performance packets" },
{0x05, "Reserved for LB-Req (Loopback Request)" },
{0x06, "Reserved for LB-Rsp (Loopback Response)"},
{0x07, "FDD (Fast Failure Detection)" },
{0, NULL }
};
static const value_string y1711_frequency_vals[] = {
{0x00, "Reserved" },
{0x01, "10 ms" },
{0x02, "20 ms" },
{0x03, "50 ms (default value)"},
{0x04, "100 ms" },
{0x05, "200 ms" },
{0x06, "500 ms" },
/* 7-255 Reserved */
{0, NULL }
};
static const value_string y1711_defect_type_vals[] = {
{0x0000, "Reserved" },
{0x0101, "dServer" },
{0x0102, "dPeerME" },
{0x0201, "dLOCV" },
{0x0202, "dTTSI_Mismatch"},
{0x0203, "dTTSI_Mismerge"},
{0x0204, "dExcess" },
{0x02FF, "dUnknown" },
{0xFFFF, "Reserved" },
{0, NULL }
};
static int
dissect_mpls_y1711(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
{
struct mplsinfo *mplsinfo;
int offset = 0;
proto_tree *mpls_y1711_tree;
int functype;
tvbuff_t *data_tvb;
static const guint8 allone[] = { 0xff, 0xff };
static const guint8 allzero[] = { 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00 };
/* Reject the packet if data is NULL */
if (data == NULL)
return 0;
mplsinfo = (struct mplsinfo *)data;
functype = tvb_get_guint8(tvb, offset);
col_append_fstr(pinfo->cinfo, COL_INFO, " (Y.1711: %s)",
(functype == 0x01) ? "CV" :
(functype == 0x02) ? "FDI" :
(functype == 0x03) ? "BDI" :
(functype == 0x07) ? "FDD" :
"reserved/unknown");
/* sanity checks */
if (tvb_reported_length(tvb) < 44) {
/*
* ITU-T Y.1711, 5.3: PDUs must have a minimum payload length of
* 44 bytes
*/
proto_tree_add_expert(tree, pinfo, &ei_mpls_y1711_minimum_payload, tvb, offset, -1);
data_tvb = tvb_new_subset_remaining(tvb, offset);
call_data_dissector(data_tvb, pinfo, tree);
return tvb_reported_length(tvb);
}
mpls_y1711_tree = proto_tree_add_subtree(tree, tvb, offset, 44, ett_mpls_y1711, NULL, "Y.1711 OAM");
/* checks for exp, bos and ttl encoding */
if (mplsinfo->label != MPLS_LABEL_OAM_ALERT)
proto_tree_add_expert_format(mpls_y1711_tree, pinfo, &ei_mpls_y1711_no_OAM_alert_label, tvb, offset - 4, 3,
"Warning: Y.1711 but no OAM alert label (%d) ?!", MPLS_LABEL_OAM_ALERT);
if (mplsinfo->exp != 0)
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_exp_bits_not_zero, tvb, offset - 2, 1);
if (mplsinfo->bos != 1)
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_s_bit_not_one, tvb, offset - 2, 1);
if (mplsinfo->ttl != 1)
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_ttl_not_one, tvb, offset - 1, 1);
/* starting dissection */
functype = tvb_get_guint8(tvb, offset);
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_function_type, tvb,
offset, 1,
ENC_LITTLE_ENDIAN);
offset++;
switch (functype) {
case 0x01: /* CV */
{
/* 3 octets reserved (all 0x00) */
if (tvb_memeql(tvb, offset, allzero, 3) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_reserved_not_zero, tvb, offset, 3);
}
offset += 3;
/* ttsi (ipv4 flavor as in RFC 2373) */
if (tvb_memeql(tvb, offset, allzero, 10) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 10);
}
offset += 10;
if (tvb_memeql(tvb, offset, allone, 2) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_ff, tvb, offset, 2);
}
offset += 2;
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsr_id, tvb, offset, 4, ENC_BIG_ENDIAN);
offset += 4;
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsp_id, tvb, offset, 4, ENC_BIG_ENDIAN);
offset += 4;
/* 18 octets of padding (all 0x00) */
if (tvb_memeql(tvb, offset, allzero, 18) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 18);
}
offset += 18;
}
break;
case 0x02: /* FDI */
case 0x03: /* BDI */
{
/* 1 octets reserved (all 0x00) */
if (tvb_memeql(tvb, offset, allzero, 1) == -1) {
proto_tree_add_expert_format(mpls_y1711_tree, pinfo, &ei_mpls_y1711_reserved_not_zero, tvb, offset, 3,
"Error: this byte is reserved and must be 0x00");
}
offset++;
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_defect_type, tvb,
offset, 2,
ENC_BIG_ENDIAN);
offset += 2;
/*
* ttsi (ipv4 flavor as in RFC 2373) is optional if not used must
* be set to all 0x00
*/
if (tvb_memeql(tvb, offset, allzero, 20) == 0) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_ttsi_not_preset, tvb, offset, 20);
offset += 20;
} else {
if (tvb_memeql(tvb, offset, allzero, 10) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 10);
}
offset += 10;
if (tvb_memeql(tvb, offset, allone, 2) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_ff, tvb, offset, 2);
}
offset += 2;
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsr_id, tvb, offset, 4, ENC_BIG_ENDIAN);
offset += 4;
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsp_id, tvb, offset, 4, ENC_BIG_ENDIAN);
offset += 4;
}
/* defect location */
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_defect_location, tvb,
offset, 4,
ENC_BIG_ENDIAN);
offset += 4;
/* 14 octets of padding (all 0x00) */
if (tvb_memeql(tvb, offset, allzero, 14) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 14);
}
offset += 14;
}
break;
case 0x07: /* FDD */
{
/* 3 octets reserved (all 0x00) */
if (tvb_memeql(tvb, offset, allzero, 3) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_reserved_not_zero, tvb, offset, 3);
}
offset += 3;
/* ttsi (ipv4 flavor as in RFC 2373) */
if (tvb_memeql(tvb, offset, allzero, 10) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 10);
}
offset += 10;
if (tvb_memeql(tvb, offset, allone, 2) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_ff, tvb, offset, 2);
}
offset += 2;
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsr_id, tvb, offset, 4, ENC_BIG_ENDIAN);
offset += 4;
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsp_id, tvb, offset, 4, ENC_BIG_ENDIAN);
offset += 4;
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_frequency, tvb,
offset, 1,
ENC_LITTLE_ENDIAN);
offset++;
/* 17 octets of padding (all 0x00) */
if (tvb_memeql(tvb, offset, allzero, 17) == -1) {
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 17);
}
offset += 17;
}
break;
default:
proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_unknown_pdu, tvb, offset - 1, -1);
return offset;
}
/* BIP16 */
proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_bip16, tvb, offset, 2,
ENC_BIG_ENDIAN);
offset += 2;
return offset;
}
void
proto_register_mpls_y1711(void)
{
static hf_register_info hf[] = {
{
&hf_mpls_y1711_function_type,
{
"Function Type", "mpls_y1711.function_type", FT_UINT8,
BASE_HEX, VALS(y1711_function_type_vals),
0x0, "Function Type codepoint", HFILL
}
},
#if 0
{
&hf_mpls_y1711_ttsi,
{
"Trail Termination Source Identifier",
"mpls_y1711.ttsi",
FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL
}
},
#endif
{
&hf_mpls_y1711_frequency,
{
"Frequency", "mpls_y1711.frequency", FT_UINT8,
BASE_HEX, VALS(y1711_frequency_vals), 0x0,
"Frequency of probe injection", HFILL
}
},
{
&hf_mpls_y1711_defect_type,
{
"Defect Type", "mpls_y1711.defect_type", FT_UINT16,
BASE_HEX, VALS(y1711_defect_type_vals), 0x0, NULL, HFILL
}
},
{
&hf_mpls_y1711_defect_location,
{
"Defect Location (AS)", "mpls_y1711.defect_location",
FT_UINT32, BASE_DEC, NULL, 0x0, "Defect Location", HFILL
}
},
{
&hf_mpls_y1711_bip16,
{
"BIP16", "mpls_y1711.bip16", FT_UINT16,
BASE_HEX, NULL, 0x0, NULL, HFILL
}
},
/* Generated from convert_proto_tree_add_text.pl */
{ &hf_mpls_y1711_lsr_id, { "LSR ID", "mpls_y1711.lsr_id", FT_IPv4, BASE_NONE, NULL, 0x0, NULL, HFILL }},
{ &hf_mpls_y1711_lsp_id, { "LSP ID", "mpls_y1711.lsp_id", FT_INT32, BASE_DEC, NULL, 0x0, NULL, HFILL }},
};
static gint *ett[] = {
&ett_mpls_y1711
};
static ei_register_info ei[] = {
/* Generated from convert_proto_tree_add_text.pl */
{ &ei_mpls_y1711_minimum_payload, { "mpls_y1711.minimum_payload", PI_MALFORMED, PI_ERROR, "Error: must have a minimum payload length of 44 bytes", EXPFILL }},
{ &ei_mpls_y1711_no_OAM_alert_label, { "mpls_y1711.no_OAM_alert_label", PI_PROTOCOL, PI_WARN, "Warning: Y.1711 but no OAM alert label (%d) ?!", EXPFILL }},
{ &ei_mpls_y1711_exp_bits_not_zero, { "mpls_y1711.exp_bits_not_0", PI_PROTOCOL, PI_WARN, "Warning: Exp bits should be 0 for Y.1711", EXPFILL }},
{ &ei_mpls_y1711_s_bit_not_one, { "mpls_y1711.s_bit_not_1", PI_PROTOCOL, PI_WARN, "Warning: S bit should be 1 for Y.1711", EXPFILL }},
{ &ei_mpls_y1711_ttl_not_one, { "mpls_y1711.ttl_not_1", PI_PROTOCOL, PI_WARN, "Warning: TTL should be 1 for Y.1711", EXPFILL }},
{ &ei_mpls_y1711_reserved_not_zero, { "mpls_y1711.reserved_not_zero", PI_PROTOCOL, PI_WARN, "Error: these bytes are reserved and must be 0x00", EXPFILL }},
{ &ei_mpls_y1711_padding_not_zero, { "mpls_y1711.padding_not_zero", PI_PROTOCOL, PI_WARN, "Error: these bytes are padding and must be 0x00", EXPFILL }},
{ &ei_mpls_y1711_padding_not_ff, { "mpls_y1711.padding_not_ff", PI_PROTOCOL, PI_WARN, "Error: these bytes are padding and must be 0xFF", EXPFILL }},
{ &ei_mpls_y1711_ttsi_not_preset, { "mpls_y1711.ttsi_not_preset", PI_PROTOCOL, PI_NOTE, "TTSI not preset (optional for FDI/BDI)", EXPFILL }},
{ &ei_mpls_y1711_unknown_pdu, { "mpls_y1711.unknown_pdu", PI_PROTOCOL, PI_WARN, "Unknown MPLS Y.1711 PDU", EXPFILL }},
};
expert_module_t* expert_mpls_y1711;
proto_mpls_y1711 =
proto_register_protocol("MPLS ITU-T Y.1711 OAM",
"MPLS ITU-T Y.1711 OAM",
"mpls_y1711");
proto_register_field_array(proto_mpls_y1711, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
expert_mpls_y1711 = expert_register_protocol(proto_mpls_y1711);
expert_register_field_array(expert_mpls_y1711, ei, array_length(ei));
mpls_y1711_handle = register_dissector("mpls_y1711", dissect_mpls_y1711, proto_mpls_y1711);
}
void
proto_reg_handoff_mpls_y1711(void)
{
dissector_add_uint("mpls.label",
MPLS_LABEL_OAM_ALERT /* 14 */,
mpls_y1711_handle);
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/