#include "emv_decoder.h" const PDOLValue pdol_term_info = {0x9F59, {0xC8, 0x80, 0x00}}; // Terminal transaction information const PDOLValue pdol_term_type = {0x9F5A, {0x00}}; // Terminal transaction type const PDOLValue pdol_merchant_type = {0x9F58, {0x01}}; // Merchant type indicator const PDOLValue pdol_term_trans_qualifies = { 0x9F66, {0x79, 0x00, 0x40, 0x80}}; // Terminal transaction qualifiers const PDOLValue pdol_amount_authorise = { 0x9F02, {0x00, 0x00, 0x00, 0x10, 0x00, 0x00}}; // Amount, authorised const PDOLValue pdol_amount = {0x9F03, {0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}; // Amount const PDOLValue pdol_country_code = {0x9F1A, {0x01, 0x24}}; // Terminal country code const PDOLValue pdol_currency_code = {0x5F2A, {0x01, 0x24}}; // Transaction currency code const PDOLValue pdol_term_verification = { 0x95, {0x00, 0x00, 0x00, 0x00, 0x00}}; // Terminal verification results const PDOLValue pdol_transaction_date = {0x9A, {0x19, 0x01, 0x01}}; // Transaction date const PDOLValue pdol_transaction_type = {0x9C, {0x00}}; // Transaction type const PDOLValue pdol_transaction_cert = {0x98, {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}; // Transaction cert const PDOLValue pdol_unpredict_number = {0x9F37, {0x82, 0x3D, 0xDE, 0x7A}}; // Unpredictable number const PDOLValue* pdol_values[] = { &pdol_term_info, &pdol_term_type, &pdol_merchant_type, &pdol_term_trans_qualifies, &pdol_amount_authorise, &pdol_amount, &pdol_country_code, &pdol_currency_code, &pdol_term_verification, &pdol_transaction_date, &pdol_transaction_type, &pdol_transaction_cert, &pdol_unpredict_number, }; static uint16_t emv_parse_TLV(uint8_t* dest, uint8_t* src, uint16_t* idx) { uint8_t len = src[*idx + 1]; memcpy(dest, &src[*idx + 2], len); *idx = *idx + len + 1; return len; } uint16_t emv_prepare_select_ppse(uint8_t* dest) { const uint8_t emv_select_ppse[] = { 0x00, 0xA4, // SELECT ppse 0x04, 0x00, // P1:By name, P2: empty 0x0e, // Lc: Data length 0x32, 0x50, 0x41, 0x59, 0x2e, 0x53, 0x59, // Data string: 0x53, 0x2e, 0x44, 0x44, 0x46, 0x30, 0x31, // 2PAY.SYS.DDF01 (PPSE) 0x00 // Le }; memcpy(dest, emv_select_ppse, sizeof(emv_select_ppse)); return sizeof(emv_select_ppse); } bool emv_decode_ppse_response(uint8_t* buff, uint16_t len, EmvApplication* app) { uint16_t i = 0; bool app_aid_found = false; while(i < len) { if(buff[i] == EMV_TAG_APP_TEMPLATE) { uint8_t app_len = buff[++i]; for(uint16_t j = i; j < i + app_len; j++) { if(buff[j] == EMV_TAG_AID) { app_aid_found = true; app->aid_len = buff[j + 1]; emv_parse_TLV(app->aid, buff, &j); } else if(buff[j] == EMV_TAG_PRIORITY) { emv_parse_TLV(&app->priority, buff, &j); } } i += app_len; } i++; } return app_aid_found; } uint16_t emv_prepare_select_app(uint8_t* dest, EmvApplication* app) { const uint8_t emv_select_header[] = { 0x00, 0xA4, // SELECT application 0x04, 0x00 // P1:By name, P2:First or only occurence }; uint16_t size = sizeof(emv_select_header); // Copy header memcpy(dest, emv_select_header, size); // Copy AID dest[size++] = app->aid_len; memcpy(&dest[size], app->aid, app->aid_len); size += app->aid_len; dest[size++] = 0; return size; } bool emv_decode_select_app_response(uint8_t* buff, uint16_t len, EmvApplication* app) { uint16_t i = 0; bool found_name = false; while(i < len) { if(buff[i] == EMV_TAG_CARD_NAME) { uint8_t name_len = buff[i + 1]; emv_parse_TLV((uint8_t*)app->name, buff, &i); app->name[name_len] = '\0'; found_name = true; } else if(((buff[i] << 8) | buff[i + 1]) == EMV_TAG_PDOL) { i++; app->pdol.size = emv_parse_TLV(app->pdol.data, buff, &i); } i++; } return found_name; } static uint16_t emv_prepare_pdol(APDU* dest, APDU* src) { bool tag_found; for(uint16_t i = 0; i < src->size; i++) { tag_found = false; for(uint8_t j = 0; j < sizeof(pdol_values) / sizeof(PDOLValue*); j++) { if(src->data[i] == pdol_values[j]->tag) { // Found tag with 1 byte length uint8_t len = src->data[++i]; memcpy(dest->data + dest->size, pdol_values[j]->data, len); dest->size += len; tag_found = true; break; } else if(((src->data[i] << 8) | src->data[i + 1]) == pdol_values[j]->tag) { // Found tag with 2 byte length i += 2; uint8_t len = src->data[i]; memcpy(dest->data + dest->size, pdol_values[j]->data, len); dest->size += len; tag_found = true; break; } } if(!tag_found) { // Unknown tag, fill zeros i += 2; uint8_t len = src->data[i]; memset(dest->data + dest->size, 0, len); dest->size += len; } } return dest->size; } uint16_t emv_prepare_get_proc_opt(uint8_t* dest, EmvApplication* app) { // Get processing option header const uint8_t emv_gpo_header[] = {0x80, 0xA8, 0x00, 0x00}; uint16_t size = sizeof(emv_gpo_header); // Copy header memcpy(dest, emv_gpo_header, size); APDU pdol_data = {0, {0}}; // Prepare and copy pdol parameters emv_prepare_pdol(&pdol_data, &app->pdol); dest[size++] = 0x02 + pdol_data.size; dest[size++] = 0x83; dest[size++] = pdol_data.size; memcpy(dest + size, pdol_data.data, pdol_data.size); size += pdol_data.size; dest[size++] = 0; return size; } bool emv_decode_get_proc_opt(uint8_t* buff, uint16_t len, EmvApplication* app) { for(uint16_t i = 0; i < len; i++) { if(buff[i] == EMV_TAG_CARD_NUM) { memcpy(app->card_number, &buff[i + 2], 8); return true; } else if(buff[i] == EMV_TAG_AFL) { app->afl.size = emv_parse_TLV(app->afl.data, buff, &i); } } return false; } uint16_t emv_prepare_read_sfi_record(uint8_t* dest, uint8_t sfi, uint8_t record_num) { const uint8_t sfi_param = (sfi << 3) | (1 << 2); const uint8_t emv_sfi_header[] = { 0x00, 0xB2, // READ RECORD record_num, sfi_param, // P1:record_number and P2:SFI 0x00 // Le }; uint16_t size = sizeof(emv_sfi_header); memcpy(dest, emv_sfi_header, size); return size; } bool emv_decode_read_sfi_record(uint8_t* buff, uint16_t len, EmvApplication* app) { for(uint16_t i = 0; i < len; i++) { if(buff[i] == EMV_TAG_PAN) { memcpy(app->card_number, &buff[i + 2], 8); return true; } } return false; }