CCID App: Refactor (#3808)

- Move iso7816 related code to its own folder
- Refactor Iso7816Callback into Iso7816Handler
- Created new file for CCID commands
- Renamed variables according to standard

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

applications/debug/ccid_test/iso7816/iso7816_t0_apdu.c

@@ -0,0 +1,85 @@
+/* Implements rudimentary iso7816-3 support for APDU (T=0) */
+#include <stdint.h>
+#include <string.h>
+#include <furi.h>
+#include <furi_hal.h>
+#include "iso7816_t0_apdu.h"
+
+//reads dataBuffer with dataLen size, translate it into a ISO7816_Command_APDU type
+//extra data will be pointed to commandDataBuffer
+uint8_t iso7816_read_command_apdu(
+    ISO7816_Command_APDU* command,
+    const uint8_t* dataBuffer,
+    uint32_t dataLen) {
+    command->CLA = dataBuffer[0];
+    command->INS = dataBuffer[1];
+    command->P1 = dataBuffer[2];
+    command->P2 = dataBuffer[3];
+
+    if(dataLen == 4) {
+        command->Lc = 0;
+        command->Le = 0;
+        command->LePresent = false;
+
+        return ISO7816_READ_COMMAND_APDU_OK;
+    } else if(dataLen == 5) {
+        //short le
+
+        command->Lc = 0;
+        command->Le = dataBuffer[4];
+        command->LePresent = true;
+
+        return ISO7816_READ_COMMAND_APDU_OK;
+    } else if(dataLen > 5 && dataBuffer[4] != 0x00) {
+        //short lc
+
+        command->Lc = dataBuffer[4];
+        if(command->Lc > 0 && command->Lc < CCID_SHORT_APDU_SIZE) { //-V560
+            memcpy(command->Data, &dataBuffer[5], command->Lc);
+
+            //does it have a short le too?
+            if(dataLen == (uint32_t)(command->Lc + 5)) {
+                command->Le = 0;
+                command->LePresent = false;
+                return ISO7816_READ_COMMAND_APDU_OK;
+            } else if(dataLen == (uint32_t)(command->Lc + 6)) {
+                command->Le = dataBuffer[dataLen - 1];
+                command->LePresent = true;
+
+                return ISO7816_READ_COMMAND_APDU_OK;
+            } else {
+                return ISO7816_READ_COMMAND_APDU_ERROR_WRONG_LENGTH;
+            }
+        } else {
+            return ISO7816_READ_COMMAND_APDU_ERROR_WRONG_LENGTH;
+        }
+    } else {
+        return ISO7816_READ_COMMAND_APDU_ERROR_WRONG_LENGTH;
+    }
+}
+
+//data buffer contains the whole APU response (response + trailer (SW1+SW2))
+void iso7816_write_response_apdu(
+    const ISO7816_Response_APDU* response,
+    uint8_t* reader_to_pc_datablock,
+    uint32_t* reader_to_pc_datablock_len) {
+    uint32_t responseDataBufferIndex = 0;
+
+    //response body
+    if(response->DataLen > 0) {
+        while(responseDataBufferIndex < response->DataLen) {
+            reader_to_pc_datablock[responseDataBufferIndex] =
+                response->Data[responseDataBufferIndex];
+            responseDataBufferIndex++;
+        }
+    }
+
+    //trailer
+    reader_to_pc_datablock[responseDataBufferIndex] = response->SW1;
+    responseDataBufferIndex++;
+
+    reader_to_pc_datablock[responseDataBufferIndex] = response->SW2;
+    responseDataBufferIndex++;
+
+    *reader_to_pc_datablock_len = responseDataBufferIndex;
+}