[efi] Use load memory address as file offset for PE sections
Mimic the behaviour of "objcopy -Obinary" by using the load memory
address (extracted from the ELF program headers) to determine the
physical placement of the section within the resulting PE file.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
diff --git a/src/util/elf2efi.c b/src/util/elf2efi.c
index 4231b1c..bacc08d 100644
--- a/src/util/elf2efi.c
+++ b/src/util/elf2efi.c
@@ -50,6 +50,7 @@
#define EFI_IMAGE_FILE_MACHINE EFI_IMAGE_FILE_32BIT_MACHINE
#define ELFCLASS ELFCLASS32
#define Elf_Ehdr Elf32_Ehdr
+#define Elf_Phdr Elf32_Phdr
#define Elf_Shdr Elf32_Shdr
#define Elf_Sym Elf32_Sym
#define Elf_Addr Elf32_Addr
@@ -65,6 +66,7 @@
#define EFI_IMAGE_FILE_MACHINE 0
#define ELFCLASS ELFCLASS64
#define Elf_Ehdr Elf64_Ehdr
+#define Elf_Phdr Elf64_Phdr
#define Elf_Shdr Elf64_Shdr
#define Elf_Sym Elf64_Sym
#define Elf_Addr Elf64_Addr
@@ -168,6 +170,9 @@
*/
#define EFI_IMAGE_ALIGN 0x1000
+/** Set PointerToRawData automatically */
+#define PTRD_AUTO 0xffffffffUL
+
struct elf_file {
void *data;
size_t len;
@@ -419,6 +424,14 @@
}
elf->ehdr = ehdr;
+ /* Check program headers */
+ if ( ( elf->len < ehdr->e_phoff ) ||
+ ( ( elf->len - ehdr->e_phoff ) < ( ehdr->e_phnum *
+ ehdr->e_phentsize ) ) ) {
+ eprintf ( "ELF program headers outside file in %s\n", name );
+ exit ( 1 );
+ }
+
/* Check section headers */
for ( i = 0 ; i < ehdr->e_shnum ; i++ ) {
offset = ( ehdr->e_shoff + ( i * ehdr->e_shentsize ) );
@@ -489,6 +502,39 @@
}
/**
+ * Get section load memory address
+ *
+ * @v elf ELF file
+ * @v shdr ELF section header
+ * @v name ELF section name
+ * @ret lma Load memory address
+ */
+static unsigned long elf_lma ( struct elf_file *elf, const Elf_Shdr *shdr,
+ const char *name ) {
+ const Elf_Ehdr *ehdr = elf->ehdr;
+ const Elf_Phdr *phdr;
+ size_t offset;
+ unsigned int i;
+
+ /* Find containing segment */
+ for ( i = 0 ; i < ehdr->e_phnum ; i++ ) {
+ offset = ( ehdr->e_phoff + ( i * ehdr->e_phentsize ) );
+ phdr = ( elf->data + offset );
+ if ( ( phdr->p_type == PT_LOAD ) &&
+ ( phdr->p_vaddr <= shdr->sh_addr ) &&
+ ( ( shdr->sh_addr - phdr->p_vaddr + shdr->sh_size ) <=
+ phdr->p_memsz ) ) {
+ /* Found matching segment */
+ return ( phdr->p_paddr +
+ ( shdr->sh_addr - phdr->p_vaddr ) );
+ }
+ }
+
+ eprintf ( "No containing segment for section %s\n", name );
+ exit ( 1 );
+}
+
+/**
* Set machine architecture
*
* @v elf ELF file
@@ -581,6 +627,9 @@
new->hdr.Misc.VirtualSize = section_memsz;
new->hdr.VirtualAddress = shdr->sh_addr;
new->hdr.SizeOfRawData = section_filesz;
+ if ( shdr->sh_type == SHT_PROGBITS ) {
+ new->hdr.PointerToRawData = elf_lma ( elf, shdr, name );
+ }
/* Fill in section characteristics and update RVA limits */
if ( ( shdr->sh_type == SHT_PROGBITS ) &&
@@ -820,6 +869,7 @@
reloc->hdr.Misc.VirtualSize = section_memsz;
reloc->hdr.VirtualAddress = pe_header->nt.OptionalHeader.SizeOfImage;
reloc->hdr.SizeOfRawData = section_filesz;
+ reloc->hdr.PointerToRawData = PTRD_AUTO;
reloc->hdr.Characteristics = ( EFI_IMAGE_SCN_CNT_INITIALIZED_DATA |
EFI_IMAGE_SCN_MEM_DISCARDABLE |
EFI_IMAGE_SCN_MEM_NOT_PAGED |
@@ -886,6 +936,7 @@
debug->hdr.Misc.VirtualSize = section_memsz;
debug->hdr.VirtualAddress = pe_header->nt.OptionalHeader.SizeOfImage;
debug->hdr.SizeOfRawData = section_filesz;
+ debug->hdr.PointerToRawData = PTRD_AUTO;
debug->hdr.Characteristics = ( EFI_IMAGE_SCN_CNT_INITIALIZED_DATA |
EFI_IMAGE_SCN_MEM_DISCARDABLE |
EFI_IMAGE_SCN_MEM_NOT_PAGED |
@@ -937,7 +988,11 @@
/* Assign raw data pointers */
for ( section = pe_sections ; section ; section = section->next ) {
if ( section->hdr.SizeOfRawData ) {
- section->hdr.PointerToRawData = fpos;
+ if ( section->hdr.PointerToRawData == PTRD_AUTO ) {
+ section->hdr.PointerToRawData = fpos;
+ } else {
+ fpos = section->hdr.PointerToRawData;
+ }
fpos += section->hdr.SizeOfRawData;
fpos = efi_file_align ( fpos );
}
@@ -947,6 +1002,12 @@
/* Write sections */
for ( section = pe_sections ; section ; section = section->next ) {
+ if ( section->hdr.PointerToRawData & ( EFI_FILE_ALIGN - 1 ) ) {
+ eprintf ( "Section %.8s file offset %x is "
+ "misaligned\n", section->hdr.Name,
+ section->hdr.PointerToRawData );
+ exit ( 1 );
+ }
if ( fseek ( pe, section->hdr.PointerToRawData,
SEEK_SET ) != 0 ) {
eprintf ( "Could not seek to %x: %s\n",
