core: sboot: Read kernel binary

Signed-off-by: Ian M. <ian@aptel.org>

1 files changed, 72 insertions, 0 deletions

diff --git a/core/file.c b/core/file.c
index 717e506..9ad1fd8 100644
--- a/core/file.c
+++ b/core/file.c
@@ -6,6 +6,18 @@
 #include <sboot/file.h>
 #include <sboot/fwi.h>
 
+static UINT64
+FileSize(EFI_FILE_HANDLE FileHandle)
+{
+    EFI_FILE_INFO *FileInfo;
+    UINT64 Size;
+
+    FileInfo = LibFileInfo(FileHandle);
+    Size = FileInfo->FileSize;
+    FreePool(FileInfo);
+    return Size;
+}
+
 EFI_STATUS
 FileGetVolume(IN EFI_HANDLE ImageHandle, OUT EFI_FILE_HANDLE *Handle)
 {
@@ -53,3 +65,63 @@ FileGetVolume(IN EFI_HANDLE ImageHandle, OUT EFI_FILE_HANDLE *Handle)
     *Handle = Volume;
     return EFI_SUCCESS;
 }
+
+EFI_STATUS
+FileReadToBuffer(IN CHAR16 *FileName, OUT VOID **Buffer)
+{
+    EFI_FILE_HANDLE Handle;
+    EFI_STATUS Status;
+    UINT64 ReadSize;
+    UINT8 *DataBuffer;
+
+    Status = uefi_call_wrapper(
+        gBootVolume->Open,
+        5,
+        gBootVolume,
+        &Handle,
+        FileName,
+        EFI_FILE_MODE_READ,
+        EFI_FILE_READ_ONLY | EFI_FILE_HIDDEN | EFI_FILE_SYSTEM
+    );
+
+    if (EFI_ERROR(Status)) {
+        Print(L"fatal: could not open %s\n", FileName);
+        return Status;
+    }
+
+    ReadSize = FileSize(Handle);
+    Status = uefi_call_wrapper(
+        gBS->AllocatePool,
+        3,
+        EfiLoaderData,
+        ReadSize,
+        &DataBuffer
+    );
+
+    if (EFI_ERROR(Status)) {
+        return EFI_OUT_OF_RESOURCES;
+    }
+
+    Status = uefi_call_wrapper(
+        Handle->Read,
+        3,
+        Handle,
+        &ReadSize,
+        DataBuffer
+    );
+
+    if (EFI_ERROR(Status)) {
+        Print(L"fatal: could not read %s\n", FileName);
+        FreePool(DataBuffer);
+        return Status;
+    }
+
+    uefi_call_wrapper(
+        Handle->Close,
+        1,
+        Handle
+    );
+
+    *Buffer = DataBuffer;
+    return EFI_SUCCESS;
+}