text: /* packet-sv.c
   * Routines for IEC 61850 Sampled Values packet dissection
   * Michael Bernhard 2008
   *
   * 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/etypes.h>
  #include <epan/expert.h>
  #include <epan/prefs.h>
  
  #include "packet-ber.h"
  #include "packet-acse.h"
  
  #include "tap.h"
  
  #include "packet-sv.h"
  
  #define PNAME  "IEC61850 Sampled Values"
  #define PSNAME "SV"
  #define PFNAME "sv"
  
  /* see IEC61850-8-1 8.2 */
  #define Q_VALIDITY_GOOD			(0x0U << 0)
  #define Q_VALIDITY_INVALID		(0x1U << 0)
  #define Q_VALIDITY_QUESTIONABLE		(0x3U << 0)
  #define Q_VALIDITY_MASK			(0x3U << 0)
  
  #define Q_OVERFLOW			(1U << 2)
  #define Q_OUTOFRANGE			(1U << 3)
  #define Q_BADREFERENCE			(1U << 4)
  #define Q_OSCILLATORY			(1U << 5)
  #define Q_FAILURE			(1U << 6)
  #define Q_OLDDATA			(1U << 7)
  #define Q_INCONSISTENT			(1U << 8)
  #define Q_INACCURATE			(1U << 9)
  
  #define Q_SOURCE_PROCESS		(0U << 10)
  #define Q_SOURCE_SUBSTITUTED		(1U << 10)
  #define Q_SOURCE_MASK			(1U << 10)
  
  #define Q_TEST				(1U << 11)
  #define Q_OPERATORBLOCKED		(1U << 12)
  
  /* see UCA Implementation Guideline for IEC 61850-9-2 */
  #define Q_DERIVED			(1U << 13)
  
  void proto_register_sv(void);
  void proto_reg_handoff_sv(void);
  
  /* Data for SV tap */
  static int sv_tap = -1;
  static sv_frame_data sv_data;
  
  /* Initialize the protocol and registered fields */
  static int proto_sv = -1;
  static int hf_sv_appid = -1;
  static int hf_sv_length = -1;
  static int hf_sv_reserve1 = -1;
  static int hf_sv_reserve2 = -1;
  static int hf_sv_phmeas_instmag_i = -1;
  static int hf_sv_phsmeas_q = -1;
  static int hf_sv_phsmeas_q_validity = -1;
  static int hf_sv_phsmeas_q_overflow = -1;
  static int hf_sv_phsmeas_q_outofrange = -1;
  static int hf_sv_phsmeas_q_badreference = -1;
  static int hf_sv_phsmeas_q_oscillatory = -1;
  static int hf_sv_phsmeas_q_failure = -1;
  static int hf_sv_phsmeas_q_olddata = -1;
  static int hf_sv_phsmeas_q_inconsistent = -1;
  static int hf_sv_phsmeas_q_inaccurate = -1;
  static int hf_sv_phsmeas_q_source = -1;
  static int hf_sv_phsmeas_q_test = -1;
  static int hf_sv_phsmeas_q_operatorblocked = -1;
  static int hf_sv_phsmeas_q_derived = -1;
  
  #include "packet-sv-hf.c"
  
  /* Initialize the subtree pointers */
  static int ett_sv = -1;
  static int ett_phsmeas = -1;
  static int ett_phsmeas_q = -1;
  
  #include "packet-sv-ett.c"
  
  static expert_field ei_sv_mal_utctime = EI_INIT;
  static expert_field ei_sv_zero_pdu = EI_INIT;
  
  static gboolean sv_decode_data_as_phsmeas = FALSE;
  
  static dissector_handle_t sv_handle;
  
  static const value_string sv_q_validity_vals[] = {
  	{ 0, "good" },
  	{ 1, "invalid" },
  	{ 3, "questionable" },
  	{ 0, NULL }
  };
  
  static const value_string sv_q_source_vals[] = {
  	{ 0, "process" },
  	{ 1, "substituted" },
  	{ 0, NULL }
  };
  
  static int
  dissect_PhsMeas1(gboolean implicit_tag, packet_info *pinfo, proto_tree *tree, tvbuff_t *tvb, int offset, int hf_id _U_)
  {
  	gint8 ber_class;
  	gboolean pc;
  	gint32 tag;
  	guint32 len;
  	proto_tree *subtree;
  	gint32 value;
  	guint32 qual;
  	guint32 i;
  
  	static const int *q_flags[] = {
  		&hf_sv_phsmeas_q_validity,
  		&hf_sv_phsmeas_q_overflow,
  		&hf_sv_phsmeas_q_outofrange,
  		&hf_sv_phsmeas_q_badreference,
  		&hf_sv_phsmeas_q_oscillatory,
  		&hf_sv_phsmeas_q_failure,
  		&hf_sv_phsmeas_q_olddata,
  		&hf_sv_phsmeas_q_inconsistent,
  		&hf_sv_phsmeas_q_inaccurate,
  		&hf_sv_phsmeas_q_source,
  		&hf_sv_phsmeas_q_test,
  		&hf_sv_phsmeas_q_operatorblocked,
  		&hf_sv_phsmeas_q_derived,
  		NULL
  		};
  
  	if (!implicit_tag) {
  		offset=dissect_ber_identifier(pinfo, tree, tvb, offset, &ber_class, &pc, &tag);
  		offset=dissect_ber_length(pinfo, tree, tvb, offset, &len, NULL);
  	} else {
  		len=tvb_reported_length_remaining(tvb, offset);
  	}
  
  	subtree = proto_tree_add_subtree(tree, tvb, offset, len, ett_phsmeas, NULL, "PhsMeas1");
  
  	sv_data.num_phsMeas = 0;
  	for (i = 0; i < len/8; i++) {
  		if (tree && subtree) {
  			value = tvb_get_ntohl(tvb, offset);
  			qual = tvb_get_ntohl(tvb, offset + 4);
  
  			proto_tree_add_item(subtree, hf_sv_phmeas_instmag_i, tvb, offset, 4, ENC_BIG_ENDIAN);
  			proto_tree_add_bitmask(subtree, tvb, offset + 4, hf_sv_phsmeas_q, ett_phsmeas_q, q_flags, ENC_BIG_ENDIAN);
  
  			if (i < IEC61850_SV_MAX_PHSMEAS_ENTRIES) {
  				sv_data.phsMeas[i].value = value;
  				sv_data.phsMeas[i].qual = qual;
  				sv_data.num_phsMeas++;
  			}
  		}
  
  		offset += 8;
  	}
  
  	return offset;
  }
  
  #include "packet-sv-fn.c"
  
  /*
  * Dissect SV PDUs inside a PPDU.
  */
  static int
  dissect_sv(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* data _U_)
  {
  	int offset = 0;
  	int old_offset;
  	guint sv_length = 0;
  	proto_item *item;
  	proto_tree *tree;
  	asn1_ctx_t asn1_ctx;
  
  	asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
  
  	item = proto_tree_add_item(parent_tree, proto_sv, tvb, 0, -1, ENC_NA);
  	tree = proto_item_add_subtree(item, ett_sv);
  
  	col_set_str(pinfo->cinfo, COL_PROTOCOL, PNAME);
  	col_clear(pinfo->cinfo, COL_INFO);
  
  	/* APPID */
  	proto_tree_add_item(tree, hf_sv_appid, tvb, offset, 2, ENC_BIG_ENDIAN);
  
  	/* Length */
  	proto_tree_add_item_ret_uint(tree, hf_sv_length, tvb, offset + 2, 2, ENC_BIG_ENDIAN, &sv_length);
  
  	/* Reserved 1 */
  	proto_tree_add_item(tree, hf_sv_reserve1, tvb, offset + 4, 2, ENC_BIG_ENDIAN);
  
  	/* Reserved 2 */
  	proto_tree_add_item(tree, hf_sv_reserve2, tvb, offset + 6, 2, ENC_BIG_ENDIAN);
  
  	offset = 8;
  	while ((tvb_reported_length_remaining(tvb, offset) > 0) && ((guint)offset < sv_length)) {
  		old_offset = offset;
  		offset = dissect_sv_SampledValues(FALSE, tvb, offset, &asn1_ctx , tree, -1);
  		if (offset == old_offset) {
  			proto_tree_add_expert(tree, pinfo, &ei_sv_zero_pdu, tvb, offset, -1);
  			break;
  		}
  	}
  
  	tap_queue_packet(sv_tap, pinfo, &sv_data);
  	return tvb_captured_length(tvb);
  }
  
  
  /*--- proto_register_sv -------------------------------------------*/
  void proto_register_sv(void) {
  
  	/* List of fields */
  	static hf_register_info hf[] = {
  		{ &hf_sv_appid,
  		{ "APPID",	"sv.appid", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL }},
  
  		{ &hf_sv_length,
  		{ "Length",	"sv.length", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
  
  		{ &hf_sv_reserve1,
  		{ "Reserved 1",	"sv.reserve1", FT_UINT16, BASE_HEX_DEC, NULL, 0x0, NULL, HFILL }},
  
  		{ &hf_sv_reserve2,
  		{ "Reserved 2",	"sv.reserve2", FT_UINT16, BASE_HEX_DEC, NULL, 0x0, NULL, HFILL }},
  
  		{ &hf_sv_phmeas_instmag_i,
  		{ "value", "sv.meas_value", FT_INT32, BASE_DEC, NULL, 0x0, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q,
  		{ "quality", "sv.meas_quality", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_validity,
  		{ "validity", "sv.meas_quality.validity", FT_UINT32, BASE_HEX, VALS(sv_q_validity_vals), Q_VALIDITY_MASK, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_overflow,
  		{ "overflow", "sv.meas_quality.overflow", FT_BOOLEAN, 32, NULL, Q_OVERFLOW, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_outofrange,
  		{ "out of range", "sv.meas_quality.outofrange", FT_BOOLEAN, 32, NULL, Q_OUTOFRANGE, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_badreference,
  		{ "bad reference", "sv.meas_quality.badreference", FT_BOOLEAN, 32, NULL, Q_BADREFERENCE, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_oscillatory,
  		{ "oscillatory", "sv.meas_quality.oscillatory", FT_BOOLEAN, 32, NULL, Q_OSCILLATORY, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_failure,
  		{ "failure", "sv.meas_quality.failure", FT_BOOLEAN, 32, NULL, Q_FAILURE, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_olddata,
  		{ "old data", "sv.meas_quality.olddata", FT_BOOLEAN, 32, NULL, Q_OLDDATA, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_inconsistent,
  		{ "inconsistent", "sv.meas_quality.inconsistent", FT_BOOLEAN, 32, NULL, Q_INCONSISTENT, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_inaccurate,
  		{ "inaccurate", "sv.meas_quality.inaccurate", FT_BOOLEAN, 32, NULL, Q_INACCURATE, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_source,
  		{ "source", "sv.meas_quality.source", FT_UINT32, BASE_HEX, VALS(sv_q_source_vals), Q_SOURCE_MASK, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_test,
  		{ "test", "sv.meas_quality.teset", FT_BOOLEAN, 32, NULL, Q_TEST, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_operatorblocked,
  		{ "operator blocked", "sv.meas_quality.operatorblocked", FT_BOOLEAN, 32, NULL, Q_OPERATORBLOCKED, NULL, HFILL}},
  
  		{ &hf_sv_phsmeas_q_derived,
  		{ "derived", "sv.meas_quality.derived", FT_BOOLEAN, 32, NULL, Q_DERIVED, NULL, HFILL}},
  
  
  #include "packet-sv-hfarr.c"
  	};
  
  	/* List of subtrees */
  	static gint *ett[] = {
  		&ett_sv,
  		&ett_phsmeas,
  		&ett_phsmeas_q,
  #include "packet-sv-ettarr.c"
  	};
  
  	static ei_register_info ei[] = {
  		{ &ei_sv_mal_utctime, { "sv.malformed.utctime", PI_MALFORMED, PI_WARN, "BER Error: malformed UTCTime encoding", EXPFILL }},
  		{ &ei_sv_zero_pdu, { "sv.zero_pdu", PI_PROTOCOL, PI_ERROR, "Internal error, zero-byte SV PDU", EXPFILL }},
  	};
  
  	expert_module_t* expert_sv;
  	module_t *sv_module;
  
  	/* Register protocol */
  	proto_sv = proto_register_protocol(PNAME, PSNAME, PFNAME);
  	sv_handle = register_dissector("sv", dissect_sv, proto_sv);
  
  	/* Register fields and subtrees */
  	proto_register_field_array(proto_sv, hf, array_length(hf));
  	proto_register_subtree_array(ett, array_length(ett));
  	expert_sv = expert_register_protocol(proto_sv);
  	expert_register_field_array(expert_sv, ei, array_length(ei));
  	sv_module = prefs_register_protocol(proto_sv, NULL);
  	prefs_register_bool_preference(sv_module, "decode_data_as_phsmeas",
  		"Force decoding of seqData as PhsMeas",
  		NULL, &sv_decode_data_as_phsmeas);
  
  	/* Register tap */
  	sv_tap = register_tap("sv");
  }
  
  /*--- proto_reg_handoff_sv --- */
  void proto_reg_handoff_sv(void) {
  	dissector_add_uint("ethertype", ETHERTYPE_IEC61850_SV, sv_handle);
  }
  