card_image: Add accessors for gamecard certificate

Used by fsp-srv/IDeviceOperator

src/core/file_sys/card_image.cpp

@@ -12,12 +12,16 @@
 #include "core/file_sys/content_archive.h"
 #include "core/file_sys/nca_metadata.h"
 #include "core/file_sys/partition_filesystem.h"
+#include "core/file_sys/romfs.h"
 #include "core/file_sys/submission_package.h"
+#include "core/file_sys/vfs_concat.h"
 #include "core/file_sys/vfs_offset.h"
+#include "core/file_sys/vfs_vector.h"
 #include "core/loader/loader.h"
 
 namespace FileSys {
 
+constexpr u64 GAMECARD_CERTIFICATE_OFFSET = 0x7000;
 constexpr std::array partition_names{
     "update",
     "normal",

src/core/file_sys/card_image.h

@@ -108,6 +108,11 @@ public:
 
     VirtualDir GetParentDirectory() const override;
 
+    // Creates a directory that contains all the NCAs in the gamecard
+    VirtualDir ConcatenatedPseudoDirectory();
+
+    std::array<u8, 0x200> GetCertificate() const;
+
 private:
     Loader::ResultStatus AddNCAFromPartition(XCIPartition part);