ntloader/include/bootapp.h

#ifndef _BOOTAPP_H
#define _BOOTAPP_H

/*
 * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

/**
 * @file
 *
 * Boot application data structures
 *
 */

#include <stdint.h>

/** A segment:offset address */
struct segoff
{
    /** Offset */
    uint16_t offset;
    /** Segment */
    uint16_t segment;
} __attribute__ ((packed));

/** A GUID */
struct guid
{
    /** 8 hex digits, big-endian */
    uint32_t a;
    /** 2 hex digits, big-endian */
    uint16_t b;
    /** 2 hex digits, big-endian */
    uint16_t c;
    /** 2 hex digits, big-endian */
    uint16_t d;
    /** 12 hex digits, big-endian */
    uint8_t e[6];
} __attribute__ ((packed));

/** Real-mode callback parameters */
struct bootapp_callback_params
{
    /** Vector */
    union
    {
        /** Interrupt number */
        uint32_t interrupt;
        /** Segment:offset address of real-mode function */
        struct segoff function;
    } vector;
    /** %eax value */
    union
    {
        struct
        {
            uint8_t al;
            uint8_t ah;
        } __attribute__ ((packed));
        uint16_t ax;
        uint32_t eax;
    };
    /** %ebx value */
    union
    {
        struct
        {
            uint8_t bl;
            uint8_t bh;
        } __attribute__ ((packed));
        uint16_t bx;
        uint32_t ebx;
    };
    /** %ecx value */
    union
    {
        struct
        {
            uint8_t cl;
            uint8_t ch;
        } __attribute__ ((packed));
        uint16_t cx;
        uint32_t ecx;
    };
    /** %edx value */
    union
    {
        struct
        {
            uint8_t dl;
            uint8_t dh;
        } __attribute__ ((packed));
        uint16_t dx;
        uint32_t edx;
    };
    /** Placeholder (for %esp?) */
    uint32_t unused_esp;
    /** Placeholder (for %ebp?) */
    uint32_t unused_ebp;
    /** %esi value */
    union
    {
        uint16_t si;
        uint32_t esi;
    };
    /** %edi value */
    union
    {
        uint16_t di;
        uint32_t edi;
    };
    /** Placeholder (for %cs?) */
    uint32_t unused_cs;
    /** %ds value */
    uint32_t ds;
    /** Placeholder (for %ss?) */
    uint32_t unused_ss;
    /** %es value */
    uint32_t es;
    /** %fs value */
    uint32_t fs;
    /** %gs value */
    uint32_t gs;
    /** eflags value */
    uint32_t eflags;
} __attribute__ ((packed));

/** eflags bits */
enum eflags
{
    CF = (1 << 0),
    PF = (1 << 2),
    AF = (1 << 4),
    ZF = (1 << 6),
    SF = (1 << 7),
    TF = (1 << 8),
    IF = (1 << 9),
    DF = (1 << 10),
    OF = (1 << 11),
};

/** Real-mode callback function table */
struct bootapp_callback_functions
{
    /**
     * Call an arbitrary real-mode interrupt
     *
     * @v params		Parameters
     */
    void (* call_interrupt) (struct bootapp_callback_params *params);
    /**
     * Call an arbitrary real-mode function
     *
     * @v params		Parameters
     */
    void (* call_real) (struct bootapp_callback_params *params);
} __attribute__ ((packed));

/** Real-mode callbacks */
struct bootapp_callback
{
    /** Real-mode callback function table */
    struct bootapp_callback_functions *fns;
    /** Drive number for INT13 calls */
    uint32_t drive;
} __attribute__ ((packed));

/** Boot application descriptor */
struct bootapp_descriptor
{
    /** Signature */
    char signature[8];
    /** Version */
    uint32_t version;
    /** Total length */
    uint32_t len;
    /** COFF machine type */
    uint32_t arch;
    /** Reserved */
    uint32_t reserved_0x14;
    /** Loaded PE image base address */
    void *pe_base;
    /** Reserved */
    uint32_t reserved_0x1c;
    /** Length of loaded PE image */
    uint32_t pe_len;
    /** Offset to memory descriptor */
    uint32_t memory;
    /** Offset to boot application entry descriptor */
    uint32_t entry;
    /** Offset to ??? */
    uint32_t xxx;
    /** Offset to callback descriptor */
    uint32_t callback;
    /** Offset to pointless descriptor */
    uint32_t pointless;
    /** Reserved */
    uint32_t reserved_0x38;
} __attribute__ ((packed));

/** "BOOT APP" magic signature */
#define BOOTAPP_SIGNATURE "BOOT APP"

/** Boot application descriptor version */
#define BOOTAPP_VERSION 2

/** i386 architecture */
#define BOOTAPP_ARCH_I386 0x014c

/** Memory region descriptor */
struct bootapp_memory_region
{
    /** Reserved (for struct list_head?) */
    uint8_t reserved[8];
    /** Start page address */
    uint64_t start_page;
    /** Reserved */
    uint8_t reserved_0x10[8];
    /** Number of pages */
    uint64_t num_pages;
    /** Reserved */
    uint8_t reserved_0x20[4];
    /** Flags */
    uint32_t flags;
} __attribute__ ((packed));

/** Memory descriptor */
struct bootapp_memory_descriptor
{
    /** Version */
    uint32_t version;
    /** Length of descriptor (excluding region descriptors) */
    uint32_t len;
    /** Number of regions */
    uint32_t num_regions;
    /** Length of each region descriptor */
    uint32_t region_len;
    /** Length of reserved area at start of each region descriptor */
    uint32_t reserved_len;
} __attribute__ ((packed));

/** Boot application memory descriptor version */
#define BOOTAPP_MEMORY_VERSION 1

/** Boot application entry descriptor */
struct bootapp_entry_descriptor
{
    /** Signature */
    char signature[8];
    /** Flags */
    uint32_t flags;
    /** GUID */
    struct guid guid;
    /** Reserved */
    uint8_t reserved[16];
} __attribute__ ((packed));

/** ??? */
struct bootapp_entry_wtf1_descriptor
{
    /** Flags */
    uint32_t flags;
    /** Length of descriptor */
    uint32_t len;
    /** Total length of following descriptors within BTAPENT */
    uint32_t extra_len;
    /** Reserved */
    uint8_t reserved[12];
} __attribute__ ((packed));

/** ??? */
struct bootapp_entry_wtf2_descriptor
{
    /** GUID */
    struct guid guid;
} __attribute__ ((packed));

/** ??? */
struct bootapp_entry_wtf3_descriptor
{
    /** Flags */
    uint32_t flags;
    /** Reserved */
    uint32_t reserved_0x04;
    /** Length of descriptor */
    uint32_t len;
    /** Reserved */
    uint32_t reserved_0x0c;
    /** Boot partition offset (in bytes) */
    uint32_t boot_partition_offset;
    /** Reserved */
    uint8_t reserved_0x14[16];
    /** MBR signature present? */
    uint32_t xxx;
    /** MBR signature */
    uint32_t mbr_signature;
    /** Reserved */
    uint8_t reserved_0x2c[26];
} __attribute__ ((packed));

/** "BTAPENT" magic signature */
#define BOOTAPP_ENTRY_SIGNATURE "BTAPENT\0"

/** Boot application entry flags
 *
 * pxeboot, etftboot, and fatboot all use a value of 0x21; I have no
 * idea what it means.
 */
#define BOOTAPP_ENTRY_FLAGS 0x21

/** Boot application callback descriptor */
struct bootapp_callback_descriptor
{
    /** Real-mode callbacks */
    struct bootapp_callback *callback;
    /** Reserved */
    uint32_t reserved;
} __attribute__ ((packed));

/** Boot application pointless descriptor */
struct bootapp_pointless_descriptor
{
    /** Version */
    uint32_t version;
    /** Reserved */
    uint8_t reserved[24];
} __attribute__ ((packed));

/** Boot application pointless descriptor version */
#define BOOTAPP_POINTLESS_VERSION 1

#endif /* _BOOTAPP_H */