HEADmaster

1 files changed, 78 insertions, 0 deletions

diff --git a/bootloader/ELF.c b/bootloader/ELF.c
new file mode 100644
index 0000000..dd2bc62
--- /dev/null
+++ b/bootloader/ELF.c
@@ -0,0 +1,78 @@
+#include "ELF.h"
+#include "memorytypes.h"
+
+#include <efi.h>
+#include <efilib.h>
+#include <efidef.h>
+
+UINTN EFIAPI elf_ceil2(float x)
+{
+  UINTN ret = x;
+  if (x - (int)x > 0) {
+      x += 1;
+      ret = (int)x;
+  }
+
+  return ret;
+}
+
+void EFIAPI PrintELFInfo(ELF * file)
+{
+  Print(L"LoadAddress: 0x%x\n", file);
+
+  Print(L"Kernel Entry Point: 0x%llx\n", file->e_entry);
+
+  Print(L"program Header offset: %d\n", file->e_phoff);
+  Print(L"Program Header Size: %d\n", file->e_phentsize);
+  Print(L"Program Header number: %d\n", file->e_phnum);
+  Print(L"== FILE PH START: 0x%llx ==\n", (uint64_t)file + file->e_phoff);
+
+  for(uint64_t i = 0; i < file->e_phnum; i++)
+  {
+    Print(L"====== PH %d\n", (uint64_t)(i+1));
+    PH* ph = (PH*)(((uint64_t)file) + file->e_phoff+i*file->e_phentsize);
+    Print(L"TOTAL LOAD offset: 0x%llx\n", (uint64_t)(file) + ph->p_offset);
+    Print(L"UNCAST LOAD offset: 0x%llx\n", (uint64_t)(file + ph->p_offset));
+    Print(L"LOAD offset: 0x%llx\n", ph->p_offset);
+    Print(L"LOAD vaddr: 0x%llx\n", ph->p_vaddr);
+    Print(L"LOAD paddr: 0x%llx\n", ph->p_paddr);
+    Print(L"LOAD size in file: 0x%llx\n", ph->p_filesz);
+    Print(L"LOAD size in memory: 0x%llx\n", ph->p_memsz);
+  }
+}
+
+Loaded_ELF* EFIAPI LoadELF(ELF* file)
+{
+  Print(L"Loading ELF file into memory\n");
+  Loaded_ELF* loaded_elf;
+
+  uefi_call_wrapper(BS->AllocatePool, 3, EfiLoaderData, sizeof(Loaded_ELF), (void**)&loaded_elf);
+
+  loaded_elf->ph_num = file->e_phnum;
+  loaded_elf->entry = file->e_entry;
+  uefi_call_wrapper(BS->AllocatePool, 3, EfiLoaderData, file->e_phnum*sizeof(Loaded_PH), (void**)&(loaded_elf->ph));
+
+  Print(L"Loading Program Segments...\n");
+  for(uint32_t i = 0; i < file->e_phnum; i++)
+  {
+    PH* ph = (PH*)(((uint64_t)file) + file->e_phoff+i*file->e_phentsize);
+    loaded_elf->ph[i].mem_size = ph->p_memsz;
+    loaded_elf->ph[i].vaddr = ph->p_vaddr;
+
+    uint64_t pages = (ph->p_memsz/1024)/4;
+
+    // uefi_call_wrapper(BS->AllocatePool, 3, EfiLoaderData, ph->p_memsz, (void**)&(loaded_elf->ph[i].data)); // <- wrong, need to allocate aligned pages
+    UINTN ipages = elf_ceil2(pages);
+    EFI_PHYSICAL_ADDRESS tmp;
+
+    /*EFI_STATUS allocstatus = */uefi_call_wrapper(BS->AllocatePages, 4, AllocateAnyPages, MEM_KERNEL, ipages, &tmp);
+    loaded_elf->ph[i].data = (void*)tmp;
+
+    // Print(L"PH: %d Addr: 0x%llX\n", i, file + ph->p_offset);
+    Print(L"LOADED PH: %d Addr: 0x%llX\n", i, loaded_elf->ph[i].data);
+    uefi_call_wrapper(BS->CopyMem, 3, loaded_elf->ph[i].data, (void*)((uint64_t)(file) + ph->p_offset), ph->p_filesz);
+  }
+  Print(L"\nFinished Loading ELF file into memory\n\n");
+
+  return loaded_elf;
+}