OvmfPkg: Make the Xen ELF header generator more flexible

Adding some flexibility to the program through optional parameters and
global define, so that other targets can use the generator.

* A global define is added so that we can choose at build time if we
  want to use 32-bit or 64-bit base structures.
* A first optional parameter is added so the user can provide the
  expected blob size of the generated binary.
* A second optional parameter is added so the user can specify an output
  file to which the generated output will be printed.

The default behavior isn't modified.

Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

1 files changed, 109 insertions, 32 deletions

diff --git a/OvmfPkg/OvmfXenElfHeaderGenerator.c b/OvmfPkg/OvmfXenElfHeaderGenerator.c
index 489060c..672129b 100644
--- a/OvmfPkg/OvmfXenElfHeaderGenerator.c
+++ b/OvmfPkg/OvmfXenElfHeaderGenerator.c
@@ -10,19 +10,31 @@
 **/

 

 #include "elf.h"

-#include "stdio.h"

+#include "fcntl.h"

+#include "stdbool.h"

 #include "stddef.h"

+#include "stdio.h"

+#include "stdlib.h"

 

 void

 print_hdr (

+  FILE    *file,

   void    *s,

-  size_t  size

+  size_t  size,

+  bool    end_delimiter

   )

 {

   char  *c = s;

 

-  while (size--) {

-    printf ("0x%02hhx, ", *(c++));

+  fprintf (file, "  ");

+  while (size-- > 1) {

+    fprintf (file, "0x%02hhx, ", *(c++));

+  }

+

+  if (end_delimiter) {

+    fprintf (file, "0x%02hhx,", *c);

+  } else {

+    fprintf (file, "0x%02hhx", *c);

   }

 }

 

@@ -36,34 +48,79 @@ typedef struct {
   uint32_t    desc;

 } xen_elfnote_phys32_entry;

 

+#define LICENSE_HDR  "\

+## @file\r\n\

+#  FDF include file that defines a PVH ELF header.\r\n\

+#\r\n\

+#  Copyright (c) 2022, Intel Corporation. All rights reserved.\r\n\

+#\r\n\

+#  SPDX-License-Identifier: BSD-2-Clause-Patent\r\n\

+#\r\n\

+##\r\n\

+\r\n\

+"

+

 int

 main (

-  void

+  int   argc,

+  char  *argv[]

   )

 {

   /* FW_SIZE */

   size_t  ovmf_blob_size = 0x00200000;

   /* Load OVMF at 1MB when running as PVH guest */

   uint32_t  ovmf_base_address = 0x00100000;

+  uint32_t  ovmfxen_pvh_entry_point;

+  size_t    offset_into_file = 0;

+  char      *endptr, *str;

+  long      param;

+  FILE      *file = stdout;

+

+  /* Parse the size parameter */

+  if (argc > 1) {

+    str   = argv[1];

+    param = strtol (str, &endptr, 10);

+    if (endptr != str) {

+      ovmf_blob_size = (size_t)param;

+    }

+  }

+

+  /* Parse the filepath parameter */

+  if (argc > 2) {

+    file = fopen (argv[2], "w");

+    fprintf (file, LICENSE_HDR);

+  }

+

   /* Xen PVH entry point */

-  uint32_t  ovmfxen_pvh_entry_point = ovmf_base_address + ovmf_blob_size - 0x30;

-  size_t    offset_into_file        = 0;

+  ovmfxen_pvh_entry_point = ovmf_base_address + ovmf_blob_size - 0x30;

 

   /* ELF file header */

+ #ifdef PVH64

+  Elf64_Ehdr  hdr = {

+ #else

   Elf32_Ehdr  hdr = {

-    .e_ident     = ELFMAG,

-    .e_type      = ET_EXEC,

-    .e_machine   = EM_386,

-    .e_version   = EV_CURRENT,

-    .e_entry     = ovmfxen_pvh_entry_point,

-    .e_flags     = R_386_NONE,

-    .e_ehsize    = sizeof (hdr),

+ #endif

+    .e_ident   = ELFMAG,

+    .e_type    = ET_EXEC,

+    .e_machine = EM_386,

+    .e_version = EV_CURRENT,

+    .e_entry   = ovmfxen_pvh_entry_point,

+    .e_flags   = R_386_NONE,

+    .e_ehsize  = sizeof (hdr),

+ #ifdef PVH64

+    .e_phentsize = sizeof (Elf64_Phdr),

+ #else

     .e_phentsize = sizeof (Elf32_Phdr),

+ #endif

   };

 

   offset_into_file += sizeof (hdr);

 

-  hdr.e_ident[EI_CLASS]   = ELFCLASS32;

+ #ifdef PVH64

+  hdr.e_ident[EI_CLASS] = ELFCLASS64;

+ #else

+  hdr.e_ident[EI_CLASS] = ELFCLASS32;

+ #endif

   hdr.e_ident[EI_DATA]    = ELFDATA2LSB;

   hdr.e_ident[EI_VERSION] = EV_CURRENT;

   hdr.e_ident[EI_OSABI]   = ELFOSABI_LINUX;

@@ -71,14 +128,22 @@ main (
   hdr.e_phoff = sizeof (hdr);

 

   /* program header */

+ #ifdef PVH64

+  Elf64_Phdr  phdr_load = {

+ #else

   Elf32_Phdr  phdr_load = {

+ #endif

     .p_type   = PT_LOAD,

     .p_offset = 0, /* load everything */

     .p_paddr  = ovmf_base_address,

     .p_filesz = ovmf_blob_size,

     .p_memsz  = ovmf_blob_size,

     .p_flags  = PF_X | PF_W | PF_R,

+ #ifdef PVH64

+    .p_align  = 4,

+ #else

     .p_align  = 0,

+ #endif

   };

 

   phdr_load.p_vaddr = phdr_load.p_paddr;

@@ -98,12 +163,20 @@ main (
       sizeof (xen_elfnote_phys32_entry) -

       offsetof (xen_elfnote_phys32_entry, desc),

   };

-  Elf32_Phdr                phdr_note = {

+ #ifdef PVH64

+  Elf64_Phdr  phdr_note = {

+ #else

+  Elf32_Phdr  phdr_note = {

+ #endif

     .p_type   = PT_NOTE,

     .p_filesz = sizeof (xen_elf_note),

     .p_memsz  = sizeof (xen_elf_note),

     .p_flags  = PF_R,

+ #ifdef PVH64

+    .p_align  = 4,

+ #else

     .p_align  = 0,

+ #endif

   };

 

   hdr.e_phnum       += 1;

@@ -120,31 +193,35 @@ main (
   size_t  hdr_size  = sizeof (hdr);

   size_t  entry_off = offsetof (typeof(hdr), e_entry);

 

-  printf ("# ELF file header\n");

-  print_hdr (&hdr, entry_off);

-  printf ("\n");

-  print_hdr (&hdr.e_entry, sizeof (hdr.e_entry));

-  printf (" # hdr.e_entry\n");

-  print_hdr (&hdr.e_entry + 1, hdr_size - entry_off - sizeof (hdr.e_entry));

+  fprintf (file, "DATA = {\r\n");

 

-  printf ("\n\n# ELF Program segment headers\n");

-  printf ("# - Load segment\n");

+  fprintf (file, "  # ELF file header\r\n");

+  print_hdr (file, &hdr, entry_off, true);

+  fprintf (file, "\r\n");

+  print_hdr (file, &hdr.e_entry, sizeof (hdr.e_entry), true);

+  fprintf (file, " # hdr.e_entry\r\n");

+  print_hdr (file, &hdr.e_entry + 1, hdr_size - entry_off - sizeof (hdr.e_entry), true);

+

+  fprintf (file, "\r\n\r\n  # ELF Program segment headers\r\n");

+  fprintf (file, "  # - Load segment\r\n");

   for (i = 0; i < sizeof (phdr_load); i += 4) {

-    print_hdr (((char *)&phdr_load) + i, 4);

-    printf ("\n");

+    print_hdr (file, ((char *)&phdr_load) + i, 4, true);

+    fprintf (file, "\r\n");

   }

 

-  printf ("# - ELFNOTE segment\n");

+  fprintf (file, "  # - ELFNOTE segment\r\n");

   for (i = 0; i < sizeof (phdr_note); i += 4) {

-    print_hdr (((char *)&phdr_note) + i, 4);

-    printf ("\n");

+    print_hdr (file, ((char *)&phdr_note) + i, 4, true);

+    fprintf (file, "\r\n");

   }

 

-  printf ("\n# XEN_ELFNOTE_PHYS32_ENTRY\n");

+  fprintf (file, "\r\n  # XEN_ELFNOTE_PHYS32_ENTRY\r\n");

   for (i = 0; i < sizeof (xen_elf_note); i += 4) {

-    print_hdr (((char *)&xen_elf_note) + i, 4);

-    printf ("\n");

+    print_hdr (file, ((char *)&xen_elf_note) + i, 4, (sizeof (xen_elf_note) - i) > 4);

+    fprintf (file, "\r\n");

   }

 

+  fprintf (file, "}\r\n");

+

   return 0;

 }