elfboot.c File Reference

ELF bootable image. More...

#include <errno.h>
#include <elf.h>
#include <gpxe/image.h>
#include <gpxe/elf.h>
#include <gpxe/features.h>
#include <gpxe/init.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER)
	FEATURE (FEATURE_IMAGE,"ELF", DHCP_EB_FEATURE_ELF, 1)
struct image_type elfboot_image_type	__image_type (PROBE_NORMAL)
	ELF image type.
static int	elfboot_exec (struct image *image)
	Execute ELF image.
static int	elfboot_load (struct image *image)
	Load ELF image into memory.

---

Detailed Description

ELF bootable image.

Definition in file elfboot.c.

---

Function Documentation

FILE_LICENCE

(

GPL2_OR_LATER

)

FEATURE	(	FEATURE_IMAGE	,
		"ELF"	,
		DHCP_EB_FEATURE_ELF	,
		1
	)

struct image_type elfboot_image_type __image_type

(

PROBE_NORMAL

)

[read]

ELF image type.

static int elfboot_exec

(

struct image *

image

)

[static]

Execute ELF image.

Parameters:

image

ELF image

Return values:

rc

Return status code

Definition at line 45 of file elfboot.c.

References __asm__(), DBGC, ECANCELED, entry, image::phys, PHYS_CODE, image::priv, shutdown(), and SHUTDOWN_BOOT.

                                                {
        physaddr_t entry = image->priv.phys;

        /* An ELF image has no callback interface, so we need to shut
         * down before invoking it.
         */
        shutdown ( SHUTDOWN_BOOT );

        /* Jump to OS with flat physical addressing */
        DBGC ( image, "ELF %p starting execution at %lx\n", image, entry );
        __asm__ __volatile__ ( PHYS_CODE ( "call *%%edi\n\t" )
                               : : "D" ( entry )
                               : "eax", "ebx", "ecx", "edx", "esi", "ebp",
                                 "memory" );

        DBGC ( image, "ELF %p returned\n", image );

        /* It isn't safe to continue after calling shutdown() */
        while ( 1 ) {}

        return -ECANCELED;  /* -EIMPOSSIBLE, anyone? */
}

static int elfboot_load

(

struct image *

image

)

[static]

Load ELF image into memory.

Parameters:

image

ELF file

Return values:

rc

Return status code

Definition at line 74 of file elfboot.c.

References copy_from_user(), image::data, DBG, DBGC, Elf32_Ehdr::e_ident, EI_CLASS, EI_DATA, EI_MAG0, EI_MAG1, EI_MAG2, EI_MAG3, EI_VERSION, elf_load(), ELFCLASS32, ELFDATA2LSB, ELFMAG0, ELFMAG1, ELFMAG2, ELFMAG3, ENOEXEC, EV_CURRENT, memcmp(), strerror(), and image::type.

                                                {
        Elf32_Ehdr ehdr;
        static const uint8_t e_ident[] = {
                [EI_MAG0]       = ELFMAG0,
                [EI_MAG1]       = ELFMAG1,
                [EI_MAG2]       = ELFMAG2,
                [EI_MAG3]       = ELFMAG3,
                [EI_CLASS]      = ELFCLASS32,
                [EI_DATA]       = ELFDATA2LSB,
                [EI_VERSION]    = EV_CURRENT,
        };
        int rc;

        /* Read ELF header */
        copy_from_user ( &ehdr, image->data, 0, sizeof ( ehdr ) );
        if ( memcmp ( ehdr.e_ident, e_ident, sizeof ( e_ident ) ) != 0 ) {
                DBG ( "Invalid ELF identifier\n" );
                return -ENOEXEC;
        }

        /* This is an ELF image, valid or otherwise */
        if ( ! image->type )
                image->type = &elfboot_image_type;

        /* Load the image using core ELF support */
        if ( ( rc = elf_load ( image ) ) != 0 ) {
                DBGC ( image, "ELF %p could not load: %s\n",
                       image, strerror ( rc ) );
                return rc;
        }

        return 0;
}