eltorito.h

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#ifndef _IPXE_ELTORITO_H
#define _IPXE_ELTORITO_H

/**
 * @file
 *
 * El Torito bootable CD-ROM specification
 *
 */

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );

#include <stdint.h>
#include <ipxe/iso9660.h>

/** An El Torito Boot Record Volume Descriptor (fixed portion) */
struct eltorito_descriptor_fixed {
        /** Descriptor type */
        uint8_t type;
        /** Identifier ("CD001") */
        uint8_t id[5];
        /** Version, must be 1 */
        uint8_t version;
        /** Boot system indicator; must be "EL TORITO SPECIFICATION" */
        uint8_t system_id[32];
} __attribute__ (( packed ));

/** An El Torito Boot Record Volume Descriptor */
struct eltorito_descriptor {
        /** Fixed portion */
        struct eltorito_descriptor_fixed fixed;
        /** Unused */
        uint8_t unused[32];
        /** Boot catalog sector */
        uint32_t sector;
} __attribute__ (( packed ));

/** El Torito Boot Record Volume Descriptor block address */
#define ELTORITO_LBA 17

/** An El Torito Boot Catalog Validation Entry */
struct eltorito_validation_entry {
        /** Header ID; must be 1 */
        uint8_t header_id;
        /** Platform ID
         *
         * 0 = 80x86
         * 1 = PowerPC
         * 2 = Mac
         */
        uint8_t platform_id;
        /** Reserved */
        uint16_t reserved;
        /** ID string */
        uint8_t id_string[24];
        /** Checksum word */
        uint16_t checksum;
        /** Signature; must be 0xaa55 */
        uint16_t signature;
} __attribute__ (( packed ));

/** El Torito platform IDs */
enum eltorito_platform_id {
        ELTORITO_PLATFORM_X86 = 0x00,
        ELTORITO_PLATFORM_POWERPC = 0x01,
        ELTORITO_PLATFORM_MAC = 0x02,
};

/** A bootable entry in the El Torito Boot Catalog */
struct eltorito_boot_entry {
        /** Boot indicator
         *
         * Must be @c ELTORITO_BOOTABLE for a bootable ISO image
         */
        uint8_t indicator;
        /** Media type
         *
         */
        uint8_t media_type;
        /** Load segment */
        uint16_t load_segment;
        /** System type */
        uint8_t filesystem;
        /** Unused */
        uint8_t reserved_a;
        /** Sector count */
        uint16_t length;
        /** Starting sector */
        uint32_t start;
        /** Unused */
        uint8_t reserved_b[20];
} __attribute__ (( packed ));

/** Boot indicator for a bootable ISO image */
#define ELTORITO_BOOTABLE 0x88

/** El Torito media types */
enum eltorito_media_type {
        /** No emulation */
        ELTORITO_NO_EMULATION = 0,
};

#endif /* _IPXE_ELTORITO_H */