Add MyKey parser (#3262)

Co-authored-by: あく <alleteam@gmail.com>

applications/main/nfc/application.fam

@@ -38,6 +38,15 @@ App(
     sources=["plugins/supported_cards/opal.c"],
 )
 
+App(
+    appid="mykey_parser",
+    apptype=FlipperAppType.PLUGIN,
+    entry_point="mykey_plugin_ep",
+    targets=["f7"],
+    requires=["nfc"],
+    sources=["plugins/supported_cards/mykey.c"],
+)
+
 App(
     appid="myki_parser",
     apptype=FlipperAppType.PLUGIN,

applications/main/nfc/plugins/supported_cards/mykey.c

@@ -0,0 +1,130 @@
+#include "nfc_supported_card_plugin.h"
+
+#include <flipper_application/flipper_application.h>
+#include <machine/endian.h>
+#include <nfc/protocols/st25tb/st25tb.h>
+
+#define TAG "MyKey"
+
+const uint32_t blankBlock18 = 0x480FCD8F, blankBlock19 = 0x070082C0;
+
+static bool mykey_is_blank(const St25tbData* data) {
+    return data->blocks[0x18] == blankBlock18 && data->blocks[0x19] == blankBlock19;
+}
+
+static bool mykey_has_lockid(const St25tbData* data) {
+    return (data->blocks[5] & 0xFF) == 0x7F;
+}
+
+static bool mykey_parse(const NfcDevice* device, FuriString* parsed_data) {
+    furi_assert(device);
+    furi_assert(parsed_data);
+
+    const St25tbData* data = nfc_device_get_data(device, NfcProtocolSt25tb);
+
+    if(data->type != St25tbType04k && data->type != St25tbTypeX4k) {
+        FURI_LOG_D(TAG, "bad type");
+        return false;
+    }
+
+    for(int i = 0; i < 5; i++) {
+        if(data->blocks[i] != 0xFFFFFFFF) {
+            FURI_LOG_D(TAG, "bad otp block %d", i);
+            return false;
+        }
+    }
+
+    if((data->blocks[8] >> 16 & 0xFF) > 0x31 || (data->blocks[8] >> 8 & 0xFF) > 0x12) {
+        FURI_LOG_D(TAG, "bad mfg date");
+        return false;
+    }
+
+    if(data->system_otp_block != 0xFEFFFFFF) {
+        FURI_LOG_D(TAG, "bad sys otp block");
+        return false;
+    }
+
+    furi_string_cat(parsed_data, "\e#MyKey\n");
+
+    if(data->blocks[6] == 0) { // Tag is actually a MyKey but it has been bricked by a reader
+        furi_string_cat(parsed_data, "\e#Bricked!\nBlock 6 is 0!");
+        return true;
+    }
+
+    bool is_blank = mykey_is_blank(data);
+    furi_string_cat_printf(parsed_data, "Serial#: %08lX\n", __bswap32(data->blocks[7]));
+    furi_string_cat_printf(parsed_data, "Blank: %s\n", is_blank ? "yes" : "no");
+    furi_string_cat_printf(parsed_data, "LockID: %s\n", mykey_has_lockid(data) ? "maybe" : "no");
+
+    uint32_t block8 = data->blocks[8];
+    furi_string_cat_printf(
+        parsed_data,
+        "Prod. date: %02lX/%02lX/%04lX",
+        block8 >> 16 & 0xFF,
+        block8 >> 8 & 0xFF,
+        0x2000 + (block8 & 0xFF));
+
+    if(!is_blank) {
+        furi_string_cat_printf(
+            parsed_data, "\nOp. count: %ld\n", __bswap32(data->blocks[0x12] & 0xFFFFFF00));
+
+        uint32_t block3C = data->blocks[0x3C];
+        if(block3C == 0xFFFFFFFF) {
+            furi_string_cat(parsed_data, "No history available!");
+        } else {
+            block3C ^= data->blocks[0x07];
+            uint32_t startingOffset = ((block3C & 0x30000000) >> 28) |
+                                      ((block3C & 0x00100000) >> 18);
+            furi_check(startingOffset < 8);
+            for(int txnOffset = 8; txnOffset > 0; txnOffset--) {
+                uint32_t txnBlock =
+                    __bswap32(data->blocks[0x34 + ((startingOffset + txnOffset) % 8)]);
+
+                if(txnBlock == 0xFFFFFFFF) {
+                    break;
+                }
+
+                uint8_t day = txnBlock >> 27;
+                uint8_t month = txnBlock >> 23 & 0xF;
+                uint16_t year = 2000 + (txnBlock >> 16 & 0x7F);
+                uint16_t credit = txnBlock & 0xFFFF;
+
+                if(txnOffset == 8) {
+                    furi_string_cat_printf(
+                        parsed_data, "Current credit: %d.%02d euros\n", credit / 100, credit % 100);
+                    furi_string_cat(parsed_data, "Op. history (newest first):");
+                }
+
+                furi_string_cat_printf(
+                    parsed_data,
+                    "\n    %02d/%02d/%04d %d.%02d",
+                    day,
+                    month,
+                    year,
+                    credit / 100,
+                    credit % 100);
+            }
+        }
+    }
+    return true;
+}
+
+/* Actual implementation of app<>plugin interface */
+static const NfcSupportedCardsPlugin mykey_plugin = {
+    .protocol = NfcProtocolSt25tb,
+    .verify = NULL,
+    .read = NULL,
+    .parse = mykey_parse,
+};
+
+/* Plugin descriptor to comply with basic plugin specification */
+static const FlipperAppPluginDescriptor mykey_plugin_descriptor = {
+    .appid = NFC_SUPPORTED_CARD_PLUGIN_APP_ID,
+    .ep_api_version = NFC_SUPPORTED_CARD_PLUGIN_API_VERSION,
+    .entry_point = &mykey_plugin,
+};
+
+/* Plugin entry point - must return a pointer to const descriptor  */
+const FlipperAppPluginDescriptor* mykey_plugin_ep() {
+    return &mykey_plugin_descriptor;
+}