nexmon – Rev 1
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/* packet-dcc.c
* Routines for Distributed Checksum Clearinghouse packet dissection
* DCC Home: http://www.rhyolite.com/anti-spam/dcc/
*
* Copyright 1999, Nathan Neulinger <nneul@umr.edu>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* Copied from packet-tftp.c
*
* 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.
*/
#include "config.h"
#include <epan/packet.h>
#include <epan/expert.h>
#include "packet-dcc.h"
void proto_register_dcc(void);
void proto_reg_handoff_dcc(void);
static int proto_dcc = -1;
static int hf_dcc_len = -1;
static int hf_dcc_pkt_vers = -1;
static int hf_dcc_op = -1;
static int hf_dcc_clientid = -1;
static int hf_dcc_opnums_host = -1;
static int hf_dcc_opnums_pid = -1;
static int hf_dcc_opnums_report = -1;
static int hf_dcc_opnums_retrans = -1;
static int hf_dcc_signature = -1;
static int hf_dcc_max_pkt_vers = -1;
static int hf_dcc_qdelay_ms = -1;
static int hf_dcc_brand = -1;
static int hf_dcc_ck_type = -1;
static int hf_dcc_ck_len = -1;
static int hf_dcc_ck_sum = -1;
static int hf_dcc_date = -1;
static int hf_dcc_target = -1;
static int hf_dcc_response_text = -1;
static int hf_dcc_adminop = -1;
static int hf_dcc_adminval = -1;
static int hf_dcc_floodop = -1;
static int hf_dcc_trace = -1;
static int hf_dcc_trace_admin = -1;
static int hf_dcc_trace_anon = -1;
static int hf_dcc_trace_client = -1;
static int hf_dcc_trace_rlim = -1;
static int hf_dcc_trace_query = -1;
static int hf_dcc_trace_ridc = -1;
static int hf_dcc_trace_flood = -1;
static int hf_dcc_addr = -1;
static int hf_dcc_id = -1;
static int hf_dcc_last_used = -1;
static int hf_dcc_requests = -1;
static int hf_dcc_pad = -1;
static int hf_dcc_unused = -1;
static gint ett_dcc = -1;
static gint ett_dcc_opnums = -1;
static gint ett_dcc_op = -1;
static gint ett_dcc_ck = -1;
static gint ett_dcc_trace = -1;
static expert_field ei_dcc_len = EI_INIT;
/* Utility macros */
#define D_SIGNATURE() \
proto_tree_add_item(dcc_optree, hf_dcc_signature, tvb, \
offset, (int)sizeof(DCC_SIGNATURE), ENC_NA); \
offset += (int)sizeof(DCC_SIGNATURE);
#define D_LABEL(hf_label, len, encoding) \
proto_tree_add_item(dcc_optree, hf_label, tvb, offset, len, encoding); \
offset += len;
#define D_TEXT(hf_label, endpad) { \
int next_offset,left; \
while (tvb_offset_exists(tvb, offset+endpad)) { \
left = tvb_reported_length_remaining(tvb,offset) - endpad; \
tvb_find_line_end(tvb, offset, left, &next_offset, \
FALSE); \
proto_tree_add_item(dcc_optree, hf_label, tvb, offset, \
next_offset - offset, ENC_ASCII|ENC_NA); \
offset = next_offset; \
} \
}
#define D_TARGET() \
proto_tree_add_item(dcc_tree, hf_dcc_target, tvb, \
offset, (int)sizeof(DCC_TGTS), ENC_BIG_ENDIAN); \
offset += (int)sizeof(DCC_TGTS);
#define D_DATE() { \
nstime_t ts; \
ts.nsecs = 0; \
ts.secs = tvb_get_ntohl(tvb,offset); \
proto_tree_add_time(dcc_optree, hf_dcc_date, tvb, offset, 4, &ts); \
offset += 4; \
}
#define D_CHECKSUM() { \
proto_tree *cktree; \
cktree = proto_tree_add_subtree_format(dcc_optree, tvb, offset, (int)sizeof(DCC_CK), \
ett_dcc_ck, NULL, "Checksum - %s", val_to_str(tvb_get_guint8(tvb,offset), \
dcc_cktype_vals, \
"Unknown Type: %u")); \
proto_tree_add_item(cktree, hf_dcc_ck_type, tvb, offset, 1, ENC_BIG_ENDIAN); \
offset += 1; \
proto_tree_add_item(cktree, hf_dcc_ck_len, tvb, offset, 1, ENC_BIG_ENDIAN); \
offset += 1; \
proto_tree_add_item(cktree, hf_dcc_ck_sum, tvb, offset, \
(int)sizeof(DCC_SUM), ENC_NA); \
offset += (int)sizeof(DCC_SUM); \
}
/* Lookup string tables */
static const value_string dcc_op_vals[] = {
{DCC_OP_INVALID, "Invalid Op"},
{DCC_OP_NOP, "No-Op"},
{DCC_OP_REPORT, "Report and Query"},
{DCC_OP_QUERY, "Query"},
{DCC_OP_QUERY_RESP, "Server Response"},
{DCC_OP_ADMN, "Admin"},
{DCC_OP_OK, "Ok"},
{DCC_OP_ERROR, "Server Failing"},
{DCC_OP_DELETE, "Delete Checksum(s)"},
{0, NULL}
};
static const value_string dcc_cktype_vals[] = {
{DCC_CK_INVALID, "Invalid/Deleted from DB when seen"},
{DCC_CK_IP, "MD5 of binary source IPv6 address"},
{DCC_CK_ENV_FROM, "MD5 of envelope Mail From value"},
{DCC_CK_FROM, "MD5 of header From: line"},
{DCC_CK_SUB, "MD5 of substitute header line"},
{DCC_CK_MESSAGE_ID, "MD5 of header Message-ID: line"},
{DCC_CK_RECEIVED, "MD5 of last header Received: line"},
{DCC_CK_BODY, "MD5 of body"},
{DCC_CK_FUZ1, "MD5 of filtered body - FUZ1"},
{DCC_CK_FUZ2, "MD5 of filtered body - FUZ2"},
{DCC_CK_FUZ3, "MD5 of filtered body - FUZ3"},
{DCC_CK_FUZ4, "MD5 of filtered body - FUZ4"},
{DCC_CK_SRVR_ID, "hostname for server-ID check "},
{DCC_CK_ENV_TO, "MD5 of envelope Rcpt To value"},
{0, NULL},
};
static const value_string dcc_adminop_vals[] = {
{DCC_AOP_OK, "Never sent"},
{DCC_AOP_STOP, "Stop Gracefully"},
{DCC_AOP_NEW_IDS, "Load keys and client IDs"},
{DCC_AOP_FLOD, "Flood control"},
{DCC_AOP_DB_UNLOCK, "Start Switch to new database"},
{DCC_AOP_DB_NEW, "Finish Switch to new database"},
{DCC_AOP_STATS, "Return counters"},
{DCC_AOP_STATS_CLEAR, "Return and zero counters"},
{DCC_AOP_TRACE_ON, "Enable tracing"},
{DCC_AOP_TRACE_OFF, "Disable tracing"},
{DCC_AOP_CUR_CLIENTS, "List clients"},
{0, NULL},
};
static const value_string dcc_target_vals[] = {
{DCC_TGTS_TOO_MANY, "Targets (>= 16777200)"},
{DCC_TGTS_OK, "Certified not spam"},
{DCC_TGTS_OK2, "Half certified not spam"},
{DCC_TGTS_DEL, "Deleted checksum"},
{DCC_TGTS_INVALID, "Invalid"},
{0, NULL},
};
static const value_string dcc_floodop_vals[] = {
{DCC_AOP_FLOD_CHECK, "Check"},
{DCC_AOP_FLOD_SHUTDOWN, "Shutdown"},
{DCC_AOP_FLOD_HALT, "Halt"},
{DCC_AOP_FLOD_RESUME, "Resume"},
{DCC_AOP_FLOD_REWIND, "Rewind"},
{DCC_AOP_FLOD_LIST, "List"},
{DCC_AOP_FLOD_STATS, "Stats"},
{DCC_AOP_FLOD_STATS_CLEAR, "Clear Stats"},
{0,NULL},
};
static gboolean
dissect_dcc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
proto_tree *dcc_tree, *dcc_optree, *dcc_opnumtree, *ti;
proto_tree *dcc_tracetree;
proto_item *len_item;
int offset = 0;
int client_is_le = 0;
int op = 0;
int i, is_response;
if (pinfo->srcport != DCC_PORT && pinfo->destport != DCC_PORT) {
/* Not the right port - not a DCC packet. */
return FALSE;
}
/* get at least a full packet structure */
if ( tvb_reported_length(tvb) < sizeof(DCC_HDR) ) {
/* Doesn't have enough bytes to contain packet header. */
return FALSE;
}
col_set_str(pinfo->cinfo, COL_PROTOCOL, "DCC");
offset = 0;
is_response = pinfo->srcport == DCC_PORT;
col_add_fstr(pinfo->cinfo, COL_INFO,
"%s: %s",
is_response ? "Response" : "Request",
val_to_str(tvb_get_guint8(tvb, offset+3),
dcc_op_vals, "Unknown Op: %u"));
ti = proto_tree_add_item(tree, proto_dcc, tvb, offset, -1,
ENC_NA);
dcc_tree = proto_item_add_subtree(ti, ett_dcc);
len_item = proto_tree_add_item(dcc_tree, hf_dcc_len, tvb,
offset, 2, ENC_BIG_ENDIAN);
if ( tvb_reported_length(tvb) < tvb_get_ntohs(tvb, offset)) {
/* Doesn't have number of bytes that header claims. */
expert_add_info(pinfo, len_item, &ei_dcc_len);
}
offset += 2;
if (tree) {
proto_tree_add_item(dcc_tree, hf_dcc_pkt_vers, tvb,
offset, 1, ENC_BIG_ENDIAN);
offset += 1;
op = tvb_get_guint8(tvb, offset);
proto_tree_add_item(dcc_tree, hf_dcc_op, tvb,
offset, 1, ENC_BIG_ENDIAN);
offset += 1;
proto_tree_add_item(dcc_tree, hf_dcc_clientid, tvb,
offset, 4, ENC_BIG_ENDIAN);
offset += 4;
dcc_opnumtree = proto_tree_add_subtree(dcc_tree, tvb, offset, -1, ett_dcc_opnums, NULL, "Operation Numbers (Opaque to Server)");
/* Note - these are indeterminate - they are sortof considered opaque to the client */
/* Make some attempt to figure out if this data is little endian, not guaranteed to be
correct if connection went through a firewall or similar. */
/* Very hokey check - if all three of pid/report/retrans look like little-endian
numbers, host is probably little endian. Probably innacurate on super-heavily-used
DCC clients though. This should be good enough for now. */
client_is_le = ( (tvb_get_guint8(tvb, offset+4) | tvb_get_guint8(tvb, offset+5)) &&
(tvb_get_guint8(tvb, offset+8) | tvb_get_guint8(tvb, offset+9)) &&
(tvb_get_guint8(tvb, offset+12) | tvb_get_guint8(tvb, offset+13)) );
proto_tree_add_item(dcc_opnumtree, hf_dcc_opnums_host, tvb,
offset, 4, client_is_le);
offset += 4;
proto_tree_add_item(dcc_opnumtree, hf_dcc_opnums_pid, tvb,
offset, 4, client_is_le);
offset += 4;
proto_tree_add_item(dcc_opnumtree, hf_dcc_opnums_report, tvb,
offset, 4, client_is_le);
offset += 4;
proto_tree_add_item(dcc_opnumtree, hf_dcc_opnums_retrans, tvb,
offset, 4, client_is_le);
offset += 4;
dcc_optree = proto_tree_add_subtree_format(dcc_tree, tvb, offset, -1, ett_dcc_op, NULL,
"Operation: %s", val_to_str(op, dcc_op_vals, "Unknown Op: %u"));
switch(op) {
case DCC_OP_NOP:
D_SIGNATURE();
break;
case DCC_OP_REPORT:
D_TARGET();
for (i=0; i<=DCC_QUERY_MAX &&
tvb_bytes_exist(tvb, offset+(int)sizeof(DCC_SIGNATURE),1); i++)
{
D_CHECKSUM();
}
D_SIGNATURE();
break;
case DCC_OP_QUERY_RESP:
for (i=0; i<=DCC_QUERY_MAX &&
tvb_bytes_exist(tvb, offset+(int)sizeof(DCC_SIGNATURE),1); i++)
{
D_TARGET();
}
D_SIGNATURE();
break;
case DCC_OP_ADMN:
if ( is_response )
{
int left_local = tvb_reported_length_remaining(tvb, offset) -
(int)sizeof(DCC_SIGNATURE);
if ( left_local == sizeof(DCC_ADMN_RESP_CLIENTS) )
{
D_LABEL(hf_dcc_addr, 16, ENC_NA);
D_LABEL(hf_dcc_id, (int)sizeof(DCC_CLNT_ID), ENC_BIG_ENDIAN);
D_LABEL(hf_dcc_last_used, 4, ENC_BIG_ENDIAN);
D_LABEL(hf_dcc_requests, 4, ENC_BIG_ENDIAN);
}
else
{
D_TEXT(hf_dcc_response_text, (int)sizeof(DCC_SIGNATURE));
}
D_SIGNATURE();
}
else
{
int aop;
D_DATE();
aop = tvb_get_guint8(tvb, offset+4);
proto_tree_add_item(dcc_optree, hf_dcc_adminop, tvb, offset+4,
1, ENC_BIG_ENDIAN);
col_append_fstr(pinfo->cinfo, COL_INFO, ", %s",
val_to_str(tvb_get_guint8(tvb,offset+4),
dcc_adminop_vals, "Unknown (%u)"));
if (aop == DCC_AOP_TRACE_ON || aop == DCC_AOP_TRACE_OFF )
{
ti = proto_tree_add_item(dcc_optree, hf_dcc_trace, tvb, offset,
4, ENC_BIG_ENDIAN);
dcc_tracetree = proto_item_add_subtree(ti, ett_dcc_trace);
proto_tree_add_item(dcc_tracetree, hf_dcc_trace_admin, tvb, offset, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(dcc_tracetree, hf_dcc_trace_anon, tvb, offset, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(dcc_tracetree, hf_dcc_trace_client, tvb, offset, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(dcc_tracetree, hf_dcc_trace_rlim, tvb, offset, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(dcc_tracetree, hf_dcc_trace_query, tvb, offset, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(dcc_tracetree, hf_dcc_trace_ridc, tvb, offset, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(dcc_tracetree, hf_dcc_trace_flood, tvb, offset, 4, ENC_BIG_ENDIAN);
}
else if ( aop == DCC_AOP_FLOD )
{
proto_tree_add_item(dcc_optree, hf_dcc_floodop,
tvb, offset, 4, ENC_BIG_ENDIAN);
col_append_fstr(pinfo->cinfo, COL_INFO, ", %s",
val_to_str(tvb_get_ntohl(tvb,offset),
dcc_floodop_vals, "Unknown (%u)"));
}
else
{
proto_tree_add_item(dcc_optree, hf_dcc_adminval,
tvb, offset, 4, ENC_BIG_ENDIAN);
}
offset += 4;
offset += 1; /* admin op we did in reverse order */
D_LABEL(hf_dcc_pad, 3, ENC_NA);
D_SIGNATURE();
}
break;
case DCC_OP_OK:
proto_tree_add_item(dcc_optree, hf_dcc_max_pkt_vers, tvb,
offset, 1, ENC_BIG_ENDIAN);
offset += 1;
D_LABEL(hf_dcc_unused, 1, ENC_NA);
proto_tree_add_item(dcc_optree, hf_dcc_qdelay_ms, tvb,
offset, 2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(dcc_optree, hf_dcc_brand, tvb,
offset, (int)sizeof(DCC_BRAND), ENC_ASCII|ENC_NA);
offset += (int)sizeof(DCC_BRAND);
D_SIGNATURE();
break;
default:
/* do nothing */
break;
}
}
return TRUE;
}
void
proto_register_dcc(void)
{
static hf_register_info hf[] = {
{ &hf_dcc_len, {
"Packet Length", "dcc.len", FT_UINT16, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_pkt_vers, {
"Packet Version", "dcc.pkt_vers", FT_UINT16, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_op, {
"Operation Type", "dcc.op", FT_UINT8, BASE_DEC,
VALS(dcc_op_vals), 0, NULL, HFILL }},
{ &hf_dcc_clientid, {
"Client ID", "dcc.clientid", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_opnums_host, {
"Host", "dcc.opnums.host", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_opnums_pid, {
"Process ID", "dcc.opnums.pid", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_opnums_report, {
"Report", "dcc.opnums.report", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_opnums_retrans, {
"Retransmission", "dcc.opnums.retrans", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_signature, {
"Signature", "dcc.signature", FT_BYTES, BASE_NONE,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_max_pkt_vers, {
"Maximum Packet Version", "dcc.max_pkt_vers", FT_UINT8, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_qdelay_ms, {
"Client Delay", "dcc.qdelay_ms", FT_UINT16, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_brand, {
"Server Brand", "dcc.brand", FT_STRING, BASE_NONE,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_ck_type, {
"Type", "dcc.checksum.type", FT_UINT8, BASE_DEC,
VALS(dcc_cktype_vals), 0, "Checksum Type", HFILL }},
{ &hf_dcc_ck_len, {
"Length", "dcc.checksum.length", FT_UINT8, BASE_DEC,
NULL, 0, "Checksum Length", HFILL }},
{ &hf_dcc_ck_sum, {
"Sum", "dcc.checksum.sum", FT_BYTES, BASE_NONE,
NULL, 0, "Checksum", HFILL }},
{ &hf_dcc_target, {
"Target", "dcc.target", FT_UINT32, BASE_HEX,
VALS(dcc_target_vals), 0, NULL, HFILL }},
{ &hf_dcc_response_text, {
"Response Text", "dcc.response_text", FT_BYTES, BASE_NONE,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_date, {
"Date", "dcc.date", FT_ABSOLUTE_TIME, ABSOLUTE_TIME_LOCAL,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_adminop, {
"Admin Op", "dcc.adminop", FT_UINT8, BASE_DEC,
VALS(dcc_adminop_vals), 0, NULL, HFILL }},
{ &hf_dcc_adminval, {
"Admin Value", "dcc.adminval", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_trace, {
"Trace Bits", "dcc.trace", FT_UINT32, BASE_HEX,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_trace_admin, {
"Admin Requests", "dcc.trace.admin", FT_BOOLEAN, 32,
NULL, 0x00000001, NULL, HFILL }},
{ &hf_dcc_trace_anon, {
"Anonymous Requests", "dcc.trace.anon", FT_BOOLEAN, 32,
NULL, 0x00000002, NULL, HFILL }},
{ &hf_dcc_trace_client, {
"Authenticated Client Requests", "dcc.trace.client", FT_BOOLEAN, 32,
NULL, 0x00000004, NULL, HFILL }},
{ &hf_dcc_trace_rlim, {
"Rate-Limited Requests", "dcc.trace.rlim", FT_BOOLEAN, 32,
NULL, 0x00000008, NULL, HFILL }},
{ &hf_dcc_trace_query, {
"Queries and Reports", "dcc.trace.query", FT_BOOLEAN, 32,
NULL, 0x00000010, NULL, HFILL }},
{ &hf_dcc_trace_ridc, {
"RID Cache Messages", "dcc.trace.ridc", FT_BOOLEAN, 32,
NULL, 0x00000020, NULL, HFILL }},
{ &hf_dcc_trace_flood, {
"Input/Output Flooding", "dcc.trace.flood", FT_BOOLEAN, 32,
NULL, 0x00000040, NULL, HFILL }},
{ &hf_dcc_floodop, {
"Flood Control Operation", "dcc.floodop", FT_UINT32, BASE_DEC,
VALS(dcc_floodop_vals), 0, NULL, HFILL }},
{ &hf_dcc_id, {
"Id", "dcc.id", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_last_used, {
"Last Used", "dcc.last_used", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_requests, {
"Requests", "dcc.requests", FT_UINT32, BASE_DEC,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_addr, {
"Addr", "dcc.addr", FT_BYTES, BASE_NONE,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_pad, {
"Pad", "dcc.pad", FT_BYTES, BASE_NONE,
NULL, 0, NULL, HFILL }},
{ &hf_dcc_unused, {
"Unused", "dcc.unused", FT_BYTES, BASE_NONE,
NULL, 0, NULL, HFILL }},
};
static gint *ett[] = {
&ett_dcc,
&ett_dcc_op,
&ett_dcc_ck,
&ett_dcc_opnums,
&ett_dcc_trace,
};
static ei_register_info ei[] = {
{ &ei_dcc_len, { "dcc.len.short", PI_MALFORMED, PI_ERROR, "Error - packet is shorter than header claims!", EXPFILL }},
};
expert_module_t* expert_dcc;
proto_dcc = proto_register_protocol("Distributed Checksum Clearinghouse protocol", "DCC", "dcc");
proto_register_field_array(proto_dcc, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
expert_dcc = expert_register_protocol(proto_dcc);
expert_register_field_array(expert_dcc, ei, array_length(ei));
}
void
proto_reg_handoff_dcc(void)
{
heur_dissector_add("udp", dissect_dcc, "Distributed Checksum Clearinghouse over UDP", "dcc_udp", proto_dcc, HEURISTIC_ENABLE);
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
* :indentSize=8:tabSize=8:noTabs=false:
*/