From 6701b4a9e1994c8a05c87a7167694bc3dd71e7d6 Mon Sep 17 00:00:00 2001 From: Sudhakar Kuppusamy Date: Wed, 23 Oct 2024 17:54:32 +0530 Subject: [PATCH 7/8] grub-mkimage: Create new ELF note for SBAT In order to store the SBAT data we create a new ELF note. The string ".sbat", zero-padded to 4 byte alignment, shall be entered in the name field. The string "SBAT"'s ASCII values, 0x53424154, should be entered in the type field. Signed-off-by: Daniel Axtens Signed-off-by: Sudhakar Kuppusamy Reviewed-by: Daniel Kiper --- include/grub/util/mkimage.h | 4 +- util/grub-mkimagexx.c | 92 +++++++++++++++++++++++++++---------- util/mkimage.c | 5 +- 3 files changed, 74 insertions(+), 27 deletions(-) diff --git a/include/grub/util/mkimage.h b/include/grub/util/mkimage.h index 6f1da89b9..881e3031f 100644 --- a/include/grub/util/mkimage.h +++ b/include/grub/util/mkimage.h @@ -51,12 +51,12 @@ grub_mkimage_load_image64 (const char *kernel_path, const struct grub_install_image_target_desc *image_target); void grub_mkimage_generate_elf32 (const struct grub_install_image_target_desc *image_target, - int note, size_t appsig_size, char **core_img, size_t *core_size, + int note, size_t appsig_size, char *sbat, char **core_img, size_t *core_size, Elf32_Addr target_addr, struct grub_mkimage_layout *layout); void grub_mkimage_generate_elf64 (const struct grub_install_image_target_desc *image_target, - int note, size_t appsig_size, char **core_img, size_t *core_size, + int note, size_t appsig_size, char *sbat, char **core_img, size_t *core_size, Elf64_Addr target_addr, struct grub_mkimage_layout *layout); diff --git a/util/grub-mkimagexx.c b/util/grub-mkimagexx.c index 9488f0525..b507d4ade 100644 --- a/util/grub-mkimagexx.c +++ b/util/grub-mkimagexx.c @@ -116,6 +116,14 @@ struct section_metadata const char *strtab; }; +#define GRUB_SBAT_NOTE_NAME ".sbat" +#define GRUB_SBAT_NOTE_TYPE 0x53424154 /* "SBAT" */ + +struct grub_sbat_note { + Elf32_Nhdr header; + char name[ALIGN_UP(sizeof(GRUB_SBAT_NOTE_NAME), 4)]; +}; + static int is_relocatable (const struct grub_install_image_target_desc *image_target) { @@ -217,7 +225,7 @@ grub_arm_reloc_jump24 (grub_uint32_t *target, Elf32_Addr sym_addr) void SUFFIX (grub_mkimage_generate_elf) (const struct grub_install_image_target_desc *image_target, - int note, size_t appsig_size, char **core_img, size_t *core_size, + int note, size_t appsig_size, char *sbat, char **core_img, size_t *core_size, Elf_Addr target_addr, struct grub_mkimage_layout *layout) { @@ -226,10 +234,17 @@ SUFFIX (grub_mkimage_generate_elf) (const struct grub_install_image_target_desc Elf_Ehdr *ehdr; Elf_Phdr *phdr; Elf_Shdr *shdr; - int header_size, footer_size = 0; + int header_size, footer_size = 0, footer_offset = 0; int phnum = 1; int shnum = 4; int string_size = sizeof (".text") + sizeof ("mods") + 1; + char *footer; + + if (sbat) + { + phnum++; + footer_size += ALIGN_UP (sizeof (struct grub_sbat_note) + layout->sbat_size, 4); + } if (appsig_size) { @@ -263,6 +278,7 @@ SUFFIX (grub_mkimage_generate_elf) (const struct grub_install_image_target_desc ehdr = (void *) elf_img; phdr = (void *) (elf_img + sizeof (*ehdr)); shdr = (void *) (elf_img + sizeof (*ehdr) + phnum * sizeof (*phdr)); + footer = elf_img + program_size + header_size; memcpy (ehdr->e_ident, ELFMAG, SELFMAG); ehdr->e_ident[EI_CLASS] = ELFCLASSXX; if (!image_target->bigendian) @@ -435,6 +451,8 @@ SUFFIX (grub_mkimage_generate_elf) (const struct grub_install_image_target_desc phdr->p_filesz = grub_host_to_target32 (XEN_NOTE_SIZE); phdr->p_memsz = 0; phdr->p_offset = grub_host_to_target32 (header_size + program_size); + footer = ptr; + footer_offset = XEN_NOTE_SIZE; } if (image_target->id == IMAGE_XEN_PVH) @@ -468,6 +486,8 @@ SUFFIX (grub_mkimage_generate_elf) (const struct grub_install_image_target_desc phdr->p_filesz = grub_host_to_target32 (XEN_PVH_NOTE_SIZE); phdr->p_memsz = 0; phdr->p_offset = grub_host_to_target32 (header_size + program_size); + footer = ptr; + footer_offset = XEN_PVH_NOTE_SIZE; } if (note) @@ -498,29 +518,55 @@ SUFFIX (grub_mkimage_generate_elf) (const struct grub_install_image_target_desc phdr->p_filesz = grub_host_to_target32 (note_size); phdr->p_memsz = 0; phdr->p_offset = grub_host_to_target32 (header_size + program_size); + footer = (elf_img + program_size + header_size + note_size); + footer_offset += note_size; } - if (appsig_size) { - int note_size = ALIGN_UP(sizeof (struct grub_appended_signature_note) + appsig_size, 4); - struct grub_appended_signature_note *note_ptr = (struct grub_appended_signature_note *) - (elf_img + program_size + header_size + (note ? sizeof (struct grub_ieee1275_note) : 0)); - - note_ptr->header.n_namesz = grub_host_to_target32 (sizeof (GRUB_APPENDED_SIGNATURE_NOTE_NAME)); - /* needs to sit at the end, so we round this up and sign some zero padding */ - note_ptr->header.n_descsz = grub_host_to_target32 (ALIGN_UP(appsig_size, 4)); - note_ptr->header.n_type = grub_host_to_target32 (GRUB_APPENDED_SIGNATURE_NOTE_TYPE); - strcpy (note_ptr->name, GRUB_APPENDED_SIGNATURE_NOTE_NAME); - - phdr++; - phdr->p_type = grub_host_to_target32 (PT_NOTE); - phdr->p_flags = grub_host_to_target32 (PF_R); - phdr->p_align = grub_host_to_target32 (image_target->voidp_sizeof); - phdr->p_vaddr = 0; - phdr->p_paddr = 0; - phdr->p_filesz = grub_host_to_target32 (note_size); - phdr->p_memsz = 0; - phdr->p_offset = grub_host_to_target32 (header_size + program_size + (note ? sizeof (struct grub_ieee1275_note) : 0)); - } + if (sbat) + { + int note_size = ALIGN_UP (sizeof (struct grub_sbat_note) + layout->sbat_size, 4); + struct grub_sbat_note *note_ptr = (struct grub_sbat_note *) footer; + + note_ptr->header.n_namesz = grub_host_to_target32 (sizeof (GRUB_SBAT_NOTE_NAME)); + note_ptr->header.n_descsz = grub_host_to_target32 (ALIGN_UP(layout->sbat_size, 4)); + note_ptr->header.n_type = grub_host_to_target32 (GRUB_SBAT_NOTE_TYPE); + memcpy (note_ptr->name, GRUB_SBAT_NOTE_NAME, sizeof (GRUB_SBAT_NOTE_NAME)); + memcpy ((char *)(note_ptr + 1), sbat, layout->sbat_size); + + phdr++; + phdr->p_type = grub_host_to_target32 (PT_NOTE); + phdr->p_flags = grub_host_to_target32 (PF_R); + phdr->p_align = grub_host_to_target32 (image_target->voidp_sizeof); + phdr->p_vaddr = 0; + phdr->p_paddr = 0; + phdr->p_filesz = grub_host_to_target32 (note_size); + phdr->p_memsz = 0; + phdr->p_offset = grub_host_to_target32 (header_size + program_size + footer_offset); + + footer += note_size; + footer_offset += note_size; + } + + if (appsig_size) + { + int note_size = ALIGN_UP (sizeof (struct grub_appended_signature_note) + appsig_size, 4); + struct grub_appended_signature_note *note_ptr = (struct grub_appended_signature_note *)footer; + note_ptr->header.n_namesz = grub_host_to_target32 (sizeof (GRUB_APPENDED_SIGNATURE_NOTE_NAME)); + /* needs to sit at the end, so we round this up and sign some zero padding */ + note_ptr->header.n_descsz = grub_host_to_target32 (ALIGN_UP (appsig_size, 4)); + note_ptr->header.n_type = grub_host_to_target32 (GRUB_APPENDED_SIGNATURE_NOTE_TYPE); + strcpy (note_ptr->name, GRUB_APPENDED_SIGNATURE_NOTE_NAME); + + phdr++; + phdr->p_type = grub_host_to_target32 (PT_NOTE); + phdr->p_flags = grub_host_to_target32 (PF_R); + phdr->p_align = grub_host_to_target32 (image_target->voidp_sizeof); + phdr->p_vaddr = 0; + phdr->p_paddr = 0; + phdr->p_filesz = grub_host_to_target32 (note_size); + phdr->p_memsz = 0; + phdr->p_offset = grub_host_to_target32 (header_size + program_size + footer_offset); + } { char *str_start = (elf_img + sizeof (*ehdr) + phnum * sizeof (*phdr) diff --git a/util/mkimage.c b/util/mkimage.c index 0737935fd..be7f02c5c 100644 --- a/util/mkimage.c +++ b/util/mkimage.c @@ -1835,6 +1835,7 @@ grub_install_generate_image (const char *dir, const char *prefix, case IMAGE_I386_IEEE1275: { grub_uint64_t target_addr; + char *sbat = NULL; if (image_target->id == IMAGE_LOONGSON_ELF) { if (comp == GRUB_COMPRESSION_NONE) @@ -1846,10 +1847,10 @@ grub_install_generate_image (const char *dir, const char *prefix, else target_addr = image_target->link_addr; if (image_target->voidp_sizeof == 4) - grub_mkimage_generate_elf32 (image_target, note, appsig_size, &core_img, + grub_mkimage_generate_elf32 (image_target, note, appsig_size, sbat, &core_img, &core_size, target_addr, &layout); else - grub_mkimage_generate_elf64 (image_target, note, appsig_size, &core_img, + grub_mkimage_generate_elf64 (image_target, note, appsig_size, sbat, &core_img, &core_size, target_addr, &layout); } break; -- 2.47.1