memdisk/eltorito.h

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2009 Shao Miller - All Rights Reserved
   4  *
   5  *   This program is free software; you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
   8  *   Boston MA 02111-1307, USA; either version 2 of the License, or
   9  *   (at your option) any later version; incorporated herein by reference.
  10  *
  11  * ----------------------------------------------------------------------- */
  12
  13 /*
  14  * eltorito.h
  15  *
  16  * EDD-4 El Torito structures and debugging routines
  17  */
  18
  19 #include <stdint.h>
  20
  21 /*
  22  * Uncomment for El Torito debugging
  23  *
  24  * #define DBG_ELTORITO 1
  25  */
  26
  27 #ifdef DBG_ELTORITO
  28 extern void eltorito_dump(uint32_t);
  29 #endif
  30
  31 /* EDD-4 Bootable Optical Disc Drive Boot Volume Descriptor */
  32 struct edd4_bvd {
  33     uint8_t boot_rec_ind;       /* Boot Record Indicator */
  34     uint8_t iso9660_id[5];      /* ISO9660 ID            */
  35     uint8_t ver;                /* Descriptor Version    */
  36     uint8_t eltorito[32];       /* "EL TORITO" etc.      */
  37     uint8_t res1[32];           /* Reserved              */
  38     uint32_t boot_cat;          /* Boot catalog sector   */
  39     uint8_t res2[1973];         /* Reserved              */
  40 } __attribute__ ((packed));
  41
  42 struct validation_entry {
  43     uint8_t header_id;          /* Header ID                      */
  44     uint8_t platform_id;        /* Platform ID                    */
  45     uint16_t res1;              /* Reserved                       */
  46     uint8_t id_string[24];      /* Manufacturer                   */
  47     uint16_t checksum;          /* Sums with whole record to zero */
  48     uint8_t key55;              /* Key byte 0x55                  */
  49     uint8_t keyAA;              /* Key byte 0xAA                  */
  50 } __attribute__ ((packed));
  51
  52 struct initial_entry {
  53     uint8_t header_id;          /* Header ID                */
  54     uint8_t media_type;         /* Media type               */
  55     uint16_t load_seg;          /* Load segment             */
  56     uint8_t system_type;        /* (Filesystem ID)          */
  57     uint8_t res1;               /* Reserved                 */
  58     uint16_t sect_count;        /* Emulated sectors to load */
  59     uint32_t load_block;        /* Starting sector of image */
  60     uint8_t res2[4];            /* Reserved                 */
  61 } __attribute__ ((packed));
  62
  63 /* EDD-4 Bootable Optical Disc Drive Boot Catalog (fixed-size portions) */
  64 struct edd4_bootcat {
  65     struct validation_entry validation_entry;
  66     struct initial_entry initial_entry;
  67 } __attribute__ ((packed));
  68
  69 /* EDD-4 CD Specification Packet */
  70 struct edd4_cd_pkt {
  71     uint8_t size;               /* Packet size                     */
  72     uint8_t type;               /* Boot media type (flags)         */
  73     uint8_t driveno;            /* INT 13h drive number            */
  74     uint8_t controller;         /* Controller index                */
  75     uint32_t start;             /* Starting LBA of image           */
  76     uint16_t devno;             /* Device number                   */
  77     uint16_t userbuf;           /* User buffer segment             */
  78     uint16_t load_seg;          /* Load segment                    */
  79     uint16_t sect_count;        /* Emulated sectors to load        */
  80     uint8_t geom1;              /* Cylinders bits 0 thru 7         */
  81     uint8_t geom2;              /* Sects/track 0 thru 5, cyls 8, 9 */
  82     uint8_t geom3;              /* Heads                           */
  83 } __attribute__ ((packed));