202 lines
6.1 KiB
C
202 lines
6.1 KiB
C
/* packet-credssp.c
|
|
* Routines for CredSSP (Credential Security Support Provider) packet dissection
|
|
* Graeme Lunt 2011
|
|
*
|
|
* Wireshark - Network traffic analyzer
|
|
* By Gerald Combs <gerald@wireshark.org>
|
|
* Copyright 1998 Gerald Combs
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0-or-later
|
|
*/
|
|
|
|
#include "config.h"
|
|
|
|
#include <epan/packet.h>
|
|
#include <epan/asn1.h>
|
|
#include <epan/tap.h>
|
|
#include <epan/exported_pdu.h>
|
|
|
|
#include "packet-ber.h"
|
|
#include "packet-dcerpc.h"
|
|
#include "packet-gssapi.h"
|
|
#include "packet-kerberos.h"
|
|
#include "packet-ntlmssp.h"
|
|
#include "packet-credssp.h"
|
|
|
|
#define PNAME "Credential Security Support Provider"
|
|
#define PSNAME "CredSSP"
|
|
#define PFNAME "credssp"
|
|
|
|
#define TS_PASSWORD_CREDS 1
|
|
#define TS_SMARTCARD_CREDS 2
|
|
#define TS_REMOTEGUARD_CREDS 6
|
|
|
|
static gint creds_type;
|
|
static gint credssp_ver;
|
|
|
|
static char kerberos_pname[] = "K\0e\0r\0b\0e\0r\0o\0s";
|
|
static char ntlm_pname[] = "N\0T\0L\0M";
|
|
|
|
#define TS_RGC_UNKNOWN 0
|
|
#define TS_RGC_KERBEROS 1
|
|
#define TS_RGC_NTLM 2
|
|
|
|
static gint credssp_TS_RGC_package;
|
|
|
|
static gint exported_pdu_tap = -1;
|
|
|
|
/* Initialize the protocol and registered fields */
|
|
static int proto_credssp = -1;
|
|
|
|
/* List of dissectors to call for negoToken data */
|
|
static heur_dissector_list_t credssp_heur_subdissector_list;
|
|
|
|
static dissector_handle_t gssapi_handle;
|
|
static dissector_handle_t gssapi_wrap_handle;
|
|
|
|
static int hf_credssp_TSPasswordCreds = -1; /* TSPasswordCreds */
|
|
static int hf_credssp_TSSmartCardCreds = -1; /* TSSmartCardCreds */
|
|
static int hf_credssp_TSRemoteGuardCreds = -1;/* TSRemoteGuardCreds */
|
|
static int hf_credssp_TSCredentials = -1; /* TSCredentials */
|
|
static int hf_credssp_decr_PublicKeyAuth = -1;/* decr_PublicKeyAuth */
|
|
#include "packet-credssp-hf.c"
|
|
|
|
/* Initialize the subtree pointers */
|
|
static gint ett_credssp = -1;
|
|
static gint ett_credssp_RGC_CredBuffer = -1;
|
|
|
|
#include "packet-credssp-ett.c"
|
|
|
|
#include "packet-credssp-fn.c"
|
|
|
|
/*
|
|
* Dissect CredSSP PDUs
|
|
*/
|
|
static int
|
|
dissect_credssp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void *data)
|
|
{
|
|
proto_item *item=NULL;
|
|
proto_tree *tree=NULL;
|
|
|
|
if(parent_tree){
|
|
item = proto_tree_add_item(parent_tree, proto_credssp, tvb, 0, -1, ENC_NA);
|
|
tree = proto_item_add_subtree(item, ett_credssp);
|
|
}
|
|
col_set_str(pinfo->cinfo, COL_PROTOCOL, "CredSSP");
|
|
col_clear(pinfo->cinfo, COL_INFO);
|
|
|
|
creds_type = -1;
|
|
credssp_ver = -1;
|
|
|
|
return dissect_TSRequest_PDU(tvb, pinfo, tree, data);
|
|
}
|
|
|
|
static gboolean
|
|
dissect_credssp_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void *data _U_)
|
|
{
|
|
asn1_ctx_t asn1_ctx;
|
|
int offset = 0;
|
|
gint8 ber_class;
|
|
gboolean pc;
|
|
gint32 tag;
|
|
guint32 length;
|
|
gint8 ver;
|
|
|
|
asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
|
|
|
|
/* Look for SEQUENCE, CONTEXT 0, and INTEGER 2 */
|
|
if(tvb_captured_length(tvb) > 7) {
|
|
offset = get_ber_identifier(tvb, offset, &ber_class, &pc, &tag);
|
|
if((ber_class == BER_CLASS_UNI) && (tag == BER_UNI_TAG_SEQUENCE) && (pc == TRUE)) {
|
|
offset = get_ber_length(tvb, offset, NULL, NULL);
|
|
offset = get_ber_identifier(tvb, offset, &ber_class, &pc, &tag);
|
|
if((ber_class == BER_CLASS_CON) && (tag == 0)) {
|
|
offset = get_ber_length(tvb, offset, NULL, NULL);
|
|
offset = get_ber_identifier(tvb, offset, &ber_class, &pc, &tag);
|
|
if((ber_class == BER_CLASS_UNI) && (tag == BER_UNI_TAG_INTEGER)) {
|
|
offset = get_ber_length(tvb, offset, &length, NULL);
|
|
ver = tvb_get_guint8(tvb, offset);
|
|
if((length == 1) && (ver > 1) && (ver < 99)) {
|
|
if (have_tap_listener(exported_pdu_tap)) {
|
|
exp_pdu_data_t *exp_pdu_data = export_pdu_create_common_tags(pinfo, "credssp", EXP_PDU_TAG_DISSECTOR_NAME);
|
|
|
|
exp_pdu_data->tvb_captured_length = tvb_captured_length(tvb);
|
|
exp_pdu_data->tvb_reported_length = tvb_reported_length(tvb);
|
|
exp_pdu_data->pdu_tvb = tvb;
|
|
|
|
tap_queue_packet(exported_pdu_tap, pinfo, exp_pdu_data);
|
|
}
|
|
dissect_credssp(tvb, pinfo, parent_tree, NULL);
|
|
return TRUE;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return FALSE;
|
|
}
|
|
|
|
|
|
/*--- proto_register_credssp -------------------------------------------*/
|
|
void proto_register_credssp(void) {
|
|
|
|
/* List of fields */
|
|
static hf_register_info hf[] =
|
|
{
|
|
{ &hf_credssp_TSPasswordCreds,
|
|
{ "TSPasswordCreds", "credssp.TSPasswordCreds",
|
|
FT_NONE, BASE_NONE, NULL, 0,
|
|
NULL, HFILL }},
|
|
{ &hf_credssp_TSSmartCardCreds,
|
|
{ "TSSmartCardCreds", "credssp.TSSmartCardCreds",
|
|
FT_NONE, BASE_NONE, NULL, 0,
|
|
NULL, HFILL }},
|
|
{ &hf_credssp_TSRemoteGuardCreds,
|
|
{ "TSRemoteGuardCreds", "credssp.TSRemoteGuardCreds",
|
|
FT_NONE, BASE_NONE, NULL, 0,
|
|
NULL, HFILL }},
|
|
{ &hf_credssp_TSCredentials,
|
|
{ "TSCredentials", "credssp.TSCredentials",
|
|
FT_NONE, BASE_NONE, NULL, 0,
|
|
NULL, HFILL }},
|
|
{ &hf_credssp_decr_PublicKeyAuth,
|
|
{ "Decrypted PublicKeyAuth (sha256)", "credssp.decr_PublicKeyAuth",
|
|
FT_BYTES, BASE_NONE, NULL, 0,
|
|
NULL, HFILL }},
|
|
#include "packet-credssp-hfarr.c"
|
|
};
|
|
|
|
/* List of subtrees */
|
|
static gint *ett[] = {
|
|
&ett_credssp,
|
|
&ett_credssp_RGC_CredBuffer,
|
|
#include "packet-credssp-ettarr.c"
|
|
};
|
|
|
|
|
|
/* Register protocol */
|
|
proto_credssp = proto_register_protocol(PNAME, PSNAME, PFNAME);
|
|
register_dissector("credssp", dissect_credssp, proto_credssp);
|
|
|
|
/* Register fields and subtrees */
|
|
proto_register_field_array(proto_credssp, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
|
|
/* heuristic dissectors for any premable e.g. CredSSP before RDP */
|
|
credssp_heur_subdissector_list = register_heur_dissector_list("credssp", proto_credssp);
|
|
|
|
}
|
|
|
|
|
|
/*--- proto_reg_handoff_credssp --- */
|
|
void proto_reg_handoff_credssp(void) {
|
|
|
|
gssapi_handle = find_dissector_add_dependency("gssapi", proto_credssp);
|
|
gssapi_wrap_handle = find_dissector_add_dependency("gssapi_verf", proto_credssp);
|
|
|
|
heur_dissector_add("tls", dissect_credssp_heur, "CredSSP over TLS", "credssp_tls", proto_credssp, HEURISTIC_ENABLE);
|
|
heur_dissector_add("rdp", dissect_credssp_heur, "CredSSP in TPKT", "credssp_tpkt", proto_credssp, HEURISTIC_ENABLE);
|
|
exported_pdu_tap = find_tap_id(EXPORT_PDU_TAP_NAME_LAYER_7);
|
|
}
|
|
|