Add fw dumping

- also fatfs is stupid
- also close files properly on a failed copy
- also check for errors during folder readouts
- also make sure holding vol- doesn't dump the keys anyway

source/keys/nca.c

@@ -0,0 +1,31 @@
+#include "nca.h"
+#include "keys.h"
+#include <libs/fatfs/ff.h>
+#include <sec/se.h>
+#include <mem/heap.h>
+
+// Thanks switchbrew https://switchbrew.org/wiki/NCA_Format
+// This function is hacky, should change it but am lazy
+int GetNcaType(char *path){
+    FIL fp;
+    u32 read_bytes = 0;
+
+    if (f_open(&fp, path, FA_READ | FA_OPEN_EXISTING))
+        return -1;
+
+    u8 *dec_header = (u8*)malloc(0x400);
+
+    if (f_lseek(&fp, 0x200) || f_read(&fp, dec_header, 32, &read_bytes) || read_bytes != 32){
+        f_close(&fp);
+        free(dec_header);
+        return -1;
+    }
+
+    se_aes_xts_crypt(7,6,0,1, dec_header + 0x200, dec_header, 32, 1);
+
+    u8 ContentType = dec_header[0x205];
+    
+    f_close(&fp);
+    free(dec_header);
+    return ContentType;
+}

source/keys/nca.h

@@ -0,0 +1,12 @@
+#pragma once
+
+enum NcaTypes {
+    Porgram = 0,
+    Meta,
+    Control,
+    Manual,
+    Data,
+    PublicData
+};
+
+int GetNcaType(char *path);