[proxmark3-svn] / client / emv / emvjson.c

//-----------------------------------------------------------------------------
// Copyright (C) 2018 Merlok
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// EMV json logic
//-----------------------------------------------------------------------------

#include "emvjson.h"
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <string.h>
#include "util.h"
#include "ui.h"
#include "proxmark3.h"
#include "emv_tags.h"

static const ApplicationDataElm ApplicationData[] = {
{0x82,    "AIP"},
{0x94,    "AFL"},

{0x5A,    "PAN"},
{0x5F34,  "PANSeqNo"},
{0x5F24,  "ExpirationDate"},
{0x5F25,  "EffectiveDate"},
{0x5F28,  "IssuerCountryCode"},

{0x50,    "ApplicationLabel"},
{0x9F08,  "VersionNumber"},
{0x9F42,  "CurrencyCode"},
{0x5F2D,  "LanguagePreference"},
{0x87,    "PriorityIndicator"},
{0x9F36,  "ATC"}, //Application Transaction Counter

{0x5F20,  "CardholderName"},

{0x9F38,  "PDOL"},
{0x8C,    "CDOL1"},
{0x8D,    "CDOL2"},

{0x9F07,  "AUC"},   // Application Usage Control
{0x9F6C,  "CTQ"},
{0x8E,    "CVMList"},
{0x9F0D,  "IACDefault"},
{0x9F0E,  "IACDeny"},
{0x9F0F,  "IACOnline"},

{0x8F,    "CertificationAuthorityPublicKeyIndex"},
{0x9F32,  "IssuerPublicKeyExponent"},
{0x92,    "IssuerPublicKeyRemainder"},
{0x90,    "IssuerPublicKeyCertificate"},
{0x9F47,  "ICCPublicKeyExponent"},
{0x9F46,  "ICCPublicKeyCertificate"},

{0x00,    "end..."}
};
int ApplicationDataLen = sizeof(ApplicationData) / sizeof(ApplicationDataElm);

char* GetApplicationDataName(tlv_tag_t tag) {
	for (int i = 0; i < ApplicationDataLen; i++)
		if (ApplicationData[i].Tag == tag)
			return ApplicationData[i].Name;
		
	return NULL;
}

int JsonSaveJsonObject(json_t *root, char *path, json_t *value) {
	json_error_t error;

	if (strlen(path) < 1)
		return 1;
	
	if (path[0] == '$') {
		if (json_path_set(root, path, value, 0, &error)) {
			PrintAndLog("ERROR: can't set json path: ", error.text);
			return 2;
		} else {
			return 0;
		}
	} else {
		return json_object_set_new(root, path, value);
	}
}

int JsonSaveInt(json_t *root, char *path, int value) {
	return JsonSaveJsonObject(root, path, json_integer(value));
}

int JsonSaveStr(json_t *root, char *path, char *value) {
	return JsonSaveJsonObject(root, path, json_string(value));
};

int JsonSaveBufAsHexCompact(json_t *elm, char *path, uint8_t *data, size_t datalen) {
	char * msg = sprint_hex_inrow(data, datalen);
	if (msg && strlen(msg) && msg[strlen(msg) - 1] == ' ')
		msg[strlen(msg) - 1] = '\0';

	return JsonSaveStr(elm, path, msg);
}

int JsonSaveBufAsHex(json_t *elm, char *path, uint8_t *data, size_t datalen) {
	char * msg = sprint_hex(data, datalen);
	if (msg && strlen(msg) && msg[strlen(msg) - 1] == ' ')
		msg[strlen(msg) - 1] = '\0';

	return JsonSaveStr(elm, path, msg);
}

int JsonSaveHex(json_t *elm, char *path, uint64_t data, int datalen) {
	uint8_t bdata[8] = {0};
	int len = 0;
	if (!datalen) {
		for (uint64_t u = 0xffffffffffffffff; u; u = u << 8) {
			if (!(data & u)) {
				break;
			}
			len++;
		}
		if (!len)
			len = 1;
	} else {
		len = datalen;
	}	
	num_to_bytes(data, len, bdata);
	
	return JsonSaveBufAsHex(elm, path, bdata, len);
}

int JsonSaveTLVValue(json_t *root, char *path, struct tlvdb *tlvdbelm) {
	const struct tlv *tlvelm = tlvdb_get_tlv(tlvdbelm);
	if (tlvelm)
		return JsonSaveBufAsHex(root, path, (uint8_t *)tlvelm->value, tlvelm->len);
	else
		return 1;	
}

int JsonSaveTLVElm(json_t *elm, char *path, struct tlv *tlvelm, bool saveName, bool saveValue, bool saveAppDataLink) {
	json_error_t error;

	if (strlen(path) < 1 || !tlvelm)
		return 1;
	
	if (path[0] == '$') {

		json_t *obj = json_path_get(elm, path);
		if (!obj) {
			obj = json_object();
		
			if (json_is_array(elm)) {
				if (json_array_append_new(elm, obj)) {
					PrintAndLog("ERROR: can't append array: %s", path);
					return 2;
				}
			} else {
				if (json_path_set(elm, path, obj, 0, &error)) {
					PrintAndLog("ERROR: can't set json path: ", error.text);
					return 2;
				}
			}
		}
		
		if (saveAppDataLink) {
			char * AppDataName = GetApplicationDataName(tlvelm->tag);
			if (AppDataName)
				JsonSaveStr(obj, "appdata", AppDataName);
		} else {		
			char * name = emv_get_tag_name(tlvelm);
			if (saveName && name && strlen(name) > 0 && strncmp(name, "Unknown", 7))
				JsonSaveStr(obj, "name", emv_get_tag_name(tlvelm));
			JsonSaveHex(obj, "tag", tlvelm->tag, 0);
			if (saveValue) {
				JsonSaveHex(obj, "length", tlvelm->len, 0);
				JsonSaveBufAsHex(obj, "value", (uint8_t *)tlvelm->value, tlvelm->len);
			};
		}
	}

	return 0;
}

int JsonSaveTLVTreeElm(json_t *elm, char *path, struct tlvdb *tlvdbelm, bool saveName, bool saveValue, bool saveAppDataLink) {
	return JsonSaveTLVElm(elm, path, (struct tlv *)tlvdb_get_tlv(tlvdbelm), saveName, saveValue, saveAppDataLink);
}

int JsonSaveTLVTree(json_t *root, json_t *elm, char *path, struct tlvdb *tlvdbelm) {
	struct tlvdb *tlvp = tlvdbelm;
	while (tlvp) {
		const struct tlv * tlvpelm = tlvdb_get_tlv(tlvp);
		char * AppDataName = NULL;
		if (tlvpelm)
			AppDataName = GetApplicationDataName(tlvpelm->tag);
		
		if (AppDataName) {
			char appdatalink[200] = {0};
			sprintf(appdatalink, "$.ApplicationData.%s", AppDataName);
			JsonSaveBufAsHex(root, appdatalink, (uint8_t *)tlvpelm->value, tlvpelm->len);
		}
		
		json_t *pelm = json_path_get(elm, path);
		if (pelm && json_is_array(pelm)) {
			json_t *appendelm = json_object();
			json_array_append_new(pelm, appendelm);
			JsonSaveTLVTreeElm(appendelm, "$", tlvp, !AppDataName, !tlvdb_elm_get_children(tlvp), AppDataName);
			pelm = appendelm;
		} else {
			JsonSaveTLVTreeElm(elm, path, tlvp, !AppDataName, !tlvdb_elm_get_children(tlvp), AppDataName);
			pelm = json_path_get(elm, path);
		}
		
		if (tlvdb_elm_get_children(tlvp)) {
			// get path element
			if(!pelm)
				return 1;
			
			// check childs element and add it if not found
			json_t *chjson = json_path_get(pelm, "$.Childs");
			if (!chjson) {
				json_object_set_new(pelm, "Childs", json_array());
				
				chjson = json_path_get(pelm, "$.Childs");
			}
			
			// check
			if (!json_is_array(chjson)) {
				PrintAndLog("E->Internal logic error. `$.Childs` is not an array.");
				break;
			}

			// Recursion
			JsonSaveTLVTree(root, chjson, "$", tlvdb_elm_get_children(tlvp));
		}

		tlvp = tlvdb_elm_get_next(tlvp);
	}
	return 0;
}

bool HexToBuffer(const char *errormsg, const char *hexvalue, uint8_t * buffer, size_t maxbufferlen, size_t *bufferlen) {
	int buflen = 0;	
	
	switch(param_gethex_to_eol(hexvalue, 0, buffer, maxbufferlen, &buflen)) {
	case 1:
		PrintAndLog("%s Invalid HEX value.", errormsg);
		return false;
	case 2:
		PrintAndLog("%s Hex value too large.", errormsg);
		return false;
	case 3:
		PrintAndLog("%s Hex value must have even number of digits.", errormsg);
		return false;
	}
	
	if (buflen > maxbufferlen) {
		PrintAndLog("%s HEX length (%d) more than %d", errormsg, *bufferlen, maxbufferlen);
		return false;
	}
	
	*bufferlen = buflen;
	
	return true;
}

int JsonLoadStr(json_t *root, char *path, char *value) {
	if (!value)
		return 1;

	json_t *jelm = json_path_get((const json_t *)root, path);
	if (!jelm || !json_is_string(jelm))
		return 2;
	
	const char * strval = json_string_value(jelm);
	if (!strval)
		return 1;
	
	memcpy(value, strval, strlen(strval));
	
	return 0;
}

int JsonLoadBufAsHex(json_t *elm, char *path, uint8_t *data, size_t maxbufferlen, size_t *datalen) {
	if (datalen)
		*datalen = 0;
	
	json_t *jelm = json_path_get((const json_t *)elm, path);
	if (!jelm || !json_is_string(jelm))
		return 1;
	
	if (!HexToBuffer("ERROR load", json_string_value(jelm), data, maxbufferlen, datalen))
		return 2;
	
	return 0;
};

bool ParamLoadFromJson(struct tlvdb *tlv) {
	json_t *root;
	json_error_t error;

	if (!tlv) {
		PrintAndLog("ERROR load params: tlv tree is NULL.");
		return false; 
	}

	// current path + file name
	const char *relfname = "emv/defparams.json"; 
	char fname[strlen(get_my_executable_directory()) + strlen(relfname) + 1];
	strcpy(fname, get_my_executable_directory());
	strcat(fname, relfname);

	root = json_load_file(fname, 0, &error);
	if (!root) {
		PrintAndLog("Load params: json error on line %d: %s", error.line, error.text);
		return false; 
	}
	
	if (!json_is_array(root)) {
		PrintAndLog("Load params: Invalid json format. root must be array.");
		return false; 
	}
	
	PrintAndLog("Load params: json(%d) OK", json_array_size(root));
	
	for(int i = 0; i < json_array_size(root); i++) {
		json_t *data, *jtag, *jlength, *jvalue;

		data = json_array_get(root, i);
		if(!json_is_object(data))
		{
			PrintAndLog("Load params: data [%d] is not an object", i + 1);
			json_decref(root);
			return false;
		}
		
		jtag = json_object_get(data, "tag");
		if(!json_is_string(jtag))
		{
			PrintAndLog("Load params: data [%d] tag is not a string", i + 1);
			json_decref(root);
			return false;
		}
		const char *tlvTag = json_string_value(jtag);

		jvalue = json_object_get(data, "value");
		if(!json_is_string(jvalue))
		{
			PrintAndLog("Load params: data [%d] value is not a string", i + 1);
			json_decref(root);
			return false;
		}
		const char *tlvValue = json_string_value(jvalue);

		jlength = json_object_get(data, "length");
		if(!json_is_number(jlength))
		{
			PrintAndLog("Load params: data [%d] length is not a number", i + 1);
			json_decref(root);
			return false;
		}
		
		int tlvLength = json_integer_value(jlength);
		if (tlvLength > 250) {
			PrintAndLog("Load params: data [%d] length more than 250", i + 1);
			json_decref(root);
			return false;
		}
		
		PrintAndLog("TLV param: %s[%d]=%s", tlvTag, tlvLength, tlvValue);
		uint8_t buf[251] = {0};
		size_t buflen = 0;
		
		// here max length must be 4, but now tlv_tag_t is 2-byte var. so let it be 2 by now...  TODO: needs refactoring tlv_tag_t...
		if (!HexToBuffer("TLV Error type:", tlvTag, buf, 2, &buflen)) { 
			json_decref(root);
			return false;
		}
		tlv_tag_t tag = 0;
		for (int i = 0; i < buflen; i++) {
			tag = (tag << 8) + buf[i];
		}	
		
		if (!HexToBuffer("TLV Error value:", tlvValue, buf, sizeof(buf) - 1, &buflen)) {
			json_decref(root);
			return false;
		}
		
		if (buflen != tlvLength) {
			PrintAndLog("Load params: data [%d] length of HEX must(%d) be identical to length in TLV param(%d)", i + 1, buflen, tlvLength);
			json_decref(root);
			return false;
		}
		
		tlvdb_change_or_add_node(tlv, tag, tlvLength, (const unsigned char *)buf);		
	}

	json_decref(root);

	return true;
}
Commit	Line	Data
95b697f0 OM	1	//-----------------------------------------------------------------------------
	2	// Copyright (C) 2018 Merlok
	3	//
	4	// This code is licensed to you under the terms of the GNU GPL, version 2 or,
	5	// at your option, any later version. See the LICENSE.txt file for the text of
	6	// the license.
	7	//-----------------------------------------------------------------------------
	8	// EMV json logic
	9	//-----------------------------------------------------------------------------
	10
	11	#include "emvjson.h"
	12	#include <ctype.h>
	13	#include <stdio.h>
	14	#include <stdlib.h>
	15	#include <inttypes.h>
	16	#include <string.h>
	17	#include "util.h"
	18	#include "ui.h"
	19	#include "proxmark3.h"
	20	#include "emv_tags.h"
	21
	22	static const ApplicationDataElm ApplicationData[] = {
	23	{0x82, "AIP"},
	24	{0x94, "AFL"},
	25
	26	{0x5A, "PAN"},
	27	{0x5F34, "PANSeqNo"},
	28	{0x5F24, "ExpirationDate"},
	29	{0x5F25, "EffectiveDate"},
	30	{0x5F28, "IssuerCountryCode"},
	31
	32	{0x50, "ApplicationLabel"},
	33	{0x9F08, "VersionNumber"},
	34	{0x9F42, "CurrencyCode"},
	35	{0x5F2D, "LanguagePreference"},
	36	{0x87, "PriorityIndicator"},
	37	{0x9F36, "ATC"}, //Application Transaction Counter
	38
	39	{0x5F20, "CardholderName"},
	40
	41	{0x9F38, "PDOL"},
	42	{0x8C, "CDOL1"},
	43	{0x8D, "CDOL2"},
	44
	45	{0x9F07, "AUC"}, // Application Usage Control
	46	{0x9F6C, "CTQ"},
	47	{0x8E, "CVMList"},
	48	{0x9F0D, "IACDefault"},
	49	{0x9F0E, "IACDeny"},
	50	{0x9F0F, "IACOnline"},
	51
	52	{0x8F, "CertificationAuthorityPublicKeyIndex"},
	53	{0x9F32, "IssuerPublicKeyExponent"},
	54	{0x92, "IssuerPublicKeyRemainder"},
	55	{0x90, "IssuerPublicKeyCertificate"},
	56	{0x9F47, "ICCPublicKeyExponent"},
	57	{0x9F46, "ICCPublicKeyCertificate"},
	58
	59	{0x00, "end..."}
	60	};
	61	int ApplicationDataLen = sizeof(ApplicationData) / sizeof(ApplicationDataElm);
	62
	63	char* GetApplicationDataName(tlv_tag_t tag) {
	64	for (int i = 0; i < ApplicationDataLen; i++)
65	if (ApplicationData[i].Tag == tag)
66	return ApplicationData[i].Name;
67
68	return NULL;
69	}
70
39cc1c87	71	int JsonSaveJsonObject(json_t root, char path, json_t *value) {
95b697f0 OM	72	json_error_t error;
	73
	74	if (strlen(path) < 1)
	75	return 1;
	76
	77	if (path[0] == '$') {
39cc1c87	78	if (json_path_set(root, path, value, 0, &error)) {
95b697f0 OM	79	PrintAndLog("ERROR: can't set json path: ", error.text);
	80	return 2;
	81	} else {
	82	return 0;
	83	}
	84	} else {
39cc1c87	85	return json_object_set_new(root, path, value);
95b697f0	86	}
39cc1c87 OM	87	}
	88
	89	int JsonSaveInt(json_t root, char path, int value) {
	90	return JsonSaveJsonObject(root, path, json_integer(value));
	91	}
	92
	93	int JsonSaveStr(json_t root, char path, char *value) {
	94	return JsonSaveJsonObject(root, path, json_string(value));
95b697f0 OM	95	};
95b697f0 OM	96
39cc1c87 OM	97	int JsonSaveBufAsHexCompact(json_t elm, char path, uint8_t *data, size_t datalen) {
	98	char * msg = sprint_hex_inrow(data, datalen);
	99	if (msg && strlen(msg) && msg[strlen(msg) - 1] == ' ')
	100	msg[strlen(msg) - 1] = '\0';
	101
	102	return JsonSaveStr(elm, path, msg);
	103	}
	104
95b697f0 OM	105	int JsonSaveBufAsHex(json_t elm, char path, uint8_t *data, size_t datalen) {
	106	char * msg = sprint_hex(data, datalen);
	107	if (msg && strlen(msg) && msg[strlen(msg) - 1] == ' ')
	108	msg[strlen(msg) - 1] = '\0';
	109
	110	return JsonSaveStr(elm, path, msg);
	111	}
	112
	113	int JsonSaveHex(json_t elm, char path, uint64_t data, int datalen) {
	114	uint8_t bdata[8] = {0};
	115	int len = 0;
	116	if (!datalen) {
	117	for (uint64_t u = 0xffffffffffffffff; u; u = u << 8) {
	118	if (!(data & u)) {
	119	break;
	120	}
	121	len++;
	122	}
	123	if (!len)
	124	len = 1;
	125	} else {
	126	len = datalen;
	127	}
	128	num_to_bytes(data, len, bdata);
	129
	130	return JsonSaveBufAsHex(elm, path, bdata, len);
	131	}
	132
	133	int JsonSaveTLVValue(json_t root, char path, struct tlvdb *tlvdbelm) {
	134	const struct tlv *tlvelm = tlvdb_get_tlv(tlvdbelm);
	135	if (tlvelm)
	136	return JsonSaveBufAsHex(root, path, (uint8_t *)tlvelm->value, tlvelm->len);
	137	else
	138	return 1;
	139	}
	140
	141	int JsonSaveTLVElm(json_t elm, char path, struct tlv *tlvelm, bool saveName, bool saveValue, bool saveAppDataLink) {
	142	json_error_t error;
	143
	144	if (strlen(path) < 1 \|\| !tlvelm)
	145	return 1;
	146
	147	if (path[0] == '$') {
	148
	149	json_t *obj = json_path_get(elm, path);
	150	if (!obj) {
	151	obj = json_object();
	152
	153	if (json_is_array(elm)) {
	154	if (json_array_append_new(elm, obj)) {
	155	PrintAndLog("ERROR: can't append array: %s", path);
	156	return 2;
	157	}
	158	} else {
	159	if (json_path_set(elm, path, obj, 0, &error)) {
	160	PrintAndLog("ERROR: can't set json path: ", error.text);
	161	return 2;
	162	}
	163	}
	164	}
	165
	166	if (saveAppDataLink) {
	167	char * AppDataName = GetApplicationDataName(tlvelm->tag);
	168	if (AppDataName)
169	JsonSaveStr(obj, "appdata", AppDataName);
170	} else {
171	char * name = emv_get_tag_name(tlvelm);
172	if (saveName && name && strlen(name) > 0 && strncmp(name, "Unknown", 7))
173	JsonSaveStr(obj, "name", emv_get_tag_name(tlvelm));
174	JsonSaveHex(obj, "tag", tlvelm->tag, 0);
175	if (saveValue) {
176	JsonSaveHex(obj, "length", tlvelm->len, 0);
177	JsonSaveBufAsHex(obj, "value", (uint8_t *)tlvelm->value, tlvelm->len);
178	};
179	}
180	}
181
182	return 0;
183	}
184
185	int JsonSaveTLVTreeElm(json_t elm, char path, struct tlvdb *tlvdbelm, bool saveName, bool saveValue, bool saveAppDataLink) {
186	return JsonSaveTLVElm(elm, path, (struct tlv *)tlvdb_get_tlv(tlvdbelm), saveName, saveValue, saveAppDataLink);
187	}
188
189	int JsonSaveTLVTree(json_t root, json_t elm, char path, struct tlvdb tlvdbelm) {
190	struct tlvdb *tlvp = tlvdbelm;
191	while (tlvp) {
192	const struct tlv * tlvpelm = tlvdb_get_tlv(tlvp);
193	char * AppDataName = NULL;
194	if (tlvpelm)
195	AppDataName = GetApplicationDataName(tlvpelm->tag);
196
197	if (AppDataName) {
198	char appdatalink[200] = {0};
199	sprintf(appdatalink, "$.ApplicationData.%s", AppDataName);
200	JsonSaveBufAsHex(root, appdatalink, (uint8_t *)tlvpelm->value, tlvpelm->len);
201	}
202
203	json_t *pelm = json_path_get(elm, path);
204	if (pelm && json_is_array(pelm)) {
205	json_t *appendelm = json_object();
206	json_array_append_new(pelm, appendelm);
207	JsonSaveTLVTreeElm(appendelm, "$", tlvp, !AppDataName, !tlvdb_elm_get_children(tlvp), AppDataName);
208	pelm = appendelm;
209	} else {
210	JsonSaveTLVTreeElm(elm, path, tlvp, !AppDataName, !tlvdb_elm_get_children(tlvp), AppDataName);
211	pelm = json_path_get(elm, path);
212	}
213
214	if (tlvdb_elm_get_children(tlvp)) {
215	// get path element
216	if(!pelm)
217	return 1;
218
219	// check childs element and add it if not found
220	json_t *chjson = json_path_get(pelm, "$.Childs");
221	if (!chjson) {
222	json_object_set_new(pelm, "Childs", json_array());
223
224	chjson = json_path_get(pelm, "$.Childs");
225	}
226
227	// check
228	if (!json_is_array(chjson)) {
229	PrintAndLog("E->Internal logic error. `$.Childs` is not an array.");
230	break;
231	}
232
233	// Recursion
234	JsonSaveTLVTree(root, chjson, "$", tlvdb_elm_get_children(tlvp));
235	}
236
237	tlvp = tlvdb_elm_get_next(tlvp);
238	}
239	return 0;
240	}
241
242	bool HexToBuffer(const char errormsg, const char hexvalue, uint8_t * buffer, size_t maxbufferlen, size_t *bufferlen) {
243	int buflen = 0;
244
245	switch(param_gethex_to_eol(hexvalue, 0, buffer, maxbufferlen, &buflen)) {
246	case 1:
247	PrintAndLog("%s Invalid HEX value.", errormsg);
248	return false;
249	case 2:
250	PrintAndLog("%s Hex value too large.", errormsg);
251	return false;
252	case 3:
253	PrintAndLog("%s Hex value must have even number of digits.", errormsg);
254	return false;
255	}
256
257	if (buflen > maxbufferlen) {
258	PrintAndLog("%s HEX length (%d) more than %d", errormsg, *bufferlen, maxbufferlen);
259	return false;
260	}
261
262	*bufferlen = buflen;
263
264	return true;
265	}
266
6b882a39 OM	267	int JsonLoadStr(json_t root, char path, char *value) {
	268	if (!value)
	269	return 1;
	270
	271	json_t jelm = json_path_get((const json_t )root, path);
	272	if (!jelm \|\| !json_is_string(jelm))
	273	return 2;
	274
	275	const char * strval = json_string_value(jelm);
	276	if (!strval)
	277	return 1;
	278
	279	memcpy(value, strval, strlen(strval));
	280
	281	return 0;
	282	}
	283
39cc1c87 OM	284	int JsonLoadBufAsHex(json_t elm, char path, uint8_t data, size_t maxbufferlen, size_t datalen) {
	285	if (datalen)
	286	*datalen = 0;
	287
	288	json_t jelm = json_path_get((const json_t )elm, path);
	289	if (!jelm \|\| !json_is_string(jelm))
	290	return 1;
	291
	292	if (!HexToBuffer("ERROR load", json_string_value(jelm), data, maxbufferlen, datalen))
	293	return 2;
	294
	295	return 0;
	296	};
	297
95b697f0 OM	298	bool ParamLoadFromJson(struct tlvdb *tlv) {
	299	json_t *root;
	300	json_error_t error;
	301
	302	if (!tlv) {
	303	PrintAndLog("ERROR load params: tlv tree is NULL.");
	304	return false;
	305	}
	306
	307	// current path + file name
	308	const char *relfname = "emv/defparams.json";
	309	char fname[strlen(get_my_executable_directory()) + strlen(relfname) + 1];
	310	strcpy(fname, get_my_executable_directory());
	311	strcat(fname, relfname);
	312
	313	root = json_load_file(fname, 0, &error);
	314	if (!root) {
	315	PrintAndLog("Load params: json error on line %d: %s", error.line, error.text);
	316	return false;
	317	}
	318
	319	if (!json_is_array(root)) {
	320	PrintAndLog("Load params: Invalid json format. root must be array.");
	321	return false;
	322	}
	323
	324	PrintAndLog("Load params: json(%d) OK", json_array_size(root));
	325
	326	for(int i = 0; i < json_array_size(root); i++) {
	327	json_t data, jtag, jlength, jvalue;
	328
	329	data = json_array_get(root, i);
	330	if(!json_is_object(data))
	331	{
	332	PrintAndLog("Load params: data [%d] is not an object", i + 1);
	333	json_decref(root);
	334	return false;
	335	}
	336
	337	jtag = json_object_get(data, "tag");
	338	if(!json_is_string(jtag))
	339	{
	340	PrintAndLog("Load params: data [%d] tag is not a string", i + 1);
	341	json_decref(root);
	342	return false;
	343	}
	344	const char *tlvTag = json_string_value(jtag);
	345
	346	jvalue = json_object_get(data, "value");
	347	if(!json_is_string(jvalue))
	348	{
	349	PrintAndLog("Load params: data [%d] value is not a string", i + 1);
	350	json_decref(root);
	351	return false;
	352	}
	353	const char *tlvValue = json_string_value(jvalue);
	354
	355	jlength = json_object_get(data, "length");
	356	if(!json_is_number(jlength))
	357	{
	358	PrintAndLog("Load params: data [%d] length is not a number", i + 1);
	359	json_decref(root);
	360	return false;
	361	}
362
363	int tlvLength = json_integer_value(jlength);
364	if (tlvLength > 250) {
365	PrintAndLog("Load params: data [%d] length more than 250", i + 1);
366	json_decref(root);
367	return false;
368	}
369
370	PrintAndLog("TLV param: %s[%d]=%s", tlvTag, tlvLength, tlvValue);
371	uint8_t buf[251] = {0};
372	size_t buflen = 0;
373
374	// here max length must be 4, but now tlv_tag_t is 2-byte var. so let it be 2 by now... TODO: needs refactoring tlv_tag_t...
375	if (!HexToBuffer("TLV Error type:", tlvTag, buf, 2, &buflen)) {
376	json_decref(root);
377	return false;
378	}
379	tlv_tag_t tag = 0;
380	for (int i = 0; i < buflen; i++) {
381	tag = (tag << 8) + buf[i];
382	}
383
384	if (!HexToBuffer("TLV Error value:", tlvValue, buf, sizeof(buf) - 1, &buflen)) {
385	json_decref(root);
386	return false;
387	}
388
389	if (buflen != tlvLength) {
390	PrintAndLog("Load params: data [%d] length of HEX must(%d) be identical to length in TLV param(%d)", i + 1, buflen, tlvLength);
391	json_decref(root);
392	return false;
393	}
394
395	tlvdb_change_or_add_node(tlv, tag, tlvLength, (const unsigned char *)buf);
396	}
397
398	json_decref(root);
399
400	return true;
401	}
402