aboutsummaryrefslogtreecommitdiff
path: root/boot/load.c
diff options
context:
space:
mode:
Diffstat (limited to 'boot/load.c')
-rw-r--r--boot/load.c851
1 files changed, 0 insertions, 851 deletions
diff --git a/boot/load.c b/boot/load.c
deleted file mode 100644
index 375d144..0000000
--- a/boot/load.c
+++ /dev/null
@@ -1,851 +0,0 @@
-// MIT License, Copyright (c) 2021 Marvin Borner
-// Independent ext2 loader - mostly copied from kernel
-
-/**
- * Some general definitions
- */
-
-typedef signed char s8;
-typedef unsigned char u8;
-
-typedef signed short s16;
-typedef unsigned short u16;
-
-typedef signed int s32;
-typedef unsigned int u32;
-
-#define NULL ((void *)0)
-#define MIN(a, b) (((a) < (b)) ? (a) : (b))
-
-#define PACKED __attribute__((packed))
-
-#define assert(exp) \
- if (!(exp)) { \
- print(__FILE__); \
- print(": "); \
- print(__func__); \
- print(": Bootloader assertion '"); \
- print(#exp); \
- print("' failed.\n"); \
- __asm__ volatile("cli\nhlt"); \
- }
-
-/**
- * ATA numbers
- */
-
-#define BLOCK_SIZE 1024
-#define BLOCK_COUNT 256 // BLOCK_SIZE / sizeof(u32)
-#define SECTOR_SIZE 512
-#define SECTOR_COUNT (BLOCK_SIZE / SECTOR_SIZE)
-
-#define ATA_PRIMARY_IO 0x1f0
-#define ATA_SECONDARY_IO 0x170
-
-#define ATA_PRIMARY 0x00
-#define ATA_SECONDARY 0x01
-#define ATA_READ 0x00
-#define ATA_WRITE 0x013
-#define ATA_MASTER 0x00
-#define ATA_SLAVE 0x01
-#define ATA_SR_BSY 0x80
-#define ATA_SR_DRDY 0x40
-#define ATA_SR_DF 0x20
-#define ATA_SR_DSC 0x10
-#define ATA_SR_DRQ 0x08
-#define ATA_SR_CORR 0x04
-#define ATA_SR_IDX 0x02
-#define ATA_SR_ERR 0x01
-#define ATA_REG_DATA 0x00
-#define ATA_REG_ERROR 0x01
-#define ATA_REG_FEATURES 0x01
-#define ATA_REG_SECCOUNT0 0x02
-#define ATA_REG_LBA0 0x03
-#define ATA_REG_LBA1 0x04
-#define ATA_REG_LBA2 0x05
-#define ATA_REG_HDDEVSEL 0x06
-#define ATA_REG_COMMAND 0x07
-#define ATA_REG_STATUS 0x07
-#define ATA_REG_SECCOUNT1 0x08
-#define ATA_REG_LBA3 0x09
-#define ATA_REG_LBA4 0x0a
-#define ATA_REG_LBA5 0x0b
-#define ATA_REG_CONTROL 0x0c
-#define ATA_REG_ALTSTATUS 0x0c
-#define ATA_REG_DEVADDRESS 0x0d
-#define ATA_CMD_READ_PIO 0x20
-#define ATA_CMD_READ_PIO_EXT 0x24
-#define ATA_CMD_READ_DMA 0xc8
-#define ATA_CMD_READ_DMA_EXT 0x25
-#define ATA_CMD_WRITE_PIO 0x30
-#define ATA_CMD_WRITE_PIO_EXT 0x34
-#define ATA_CMD_WRITE_DMA 0xca
-#define ATA_CMD_WRITE_DMA_EXT 0x35
-#define ATA_CMD_CACHE_FLUSH 0xe7
-#define ATA_CMD_CACHE_FLUSH_EXT 0xea
-#define ATA_CMD_PACKET 0xa0
-#define ATA_CMD_IDENTIFY_PACKET 0xa1
-#define ATA_CMD_IDENTIFY 0xec
-#define ATA_IDENT_DEVICETYPE 0
-#define ATA_IDENT_CYLINDERS 2
-#define ATA_IDENT_HEADS 6
-#define ATA_IDENT_SECTORS 12
-#define ATA_IDENT_SERIAL 20
-#define ATA_IDENT_MODEL 54
-#define ATA_IDENT_CAPABILITIES 98
-#define ATA_IDENT_FIELDVALID 106
-#define ATA_IDENT_MAX_LBA 120
-#define ATA_IDENT_COMMANDSETS 164
-#define ATA_IDENT_MAX_LBA_EXT 200
-
-/**
- * ELF stuff
- */
-
-#define ELF_MAG0 0x7F
-#define ELF_MAG1 'E'
-#define ELF_MAG2 'L'
-#define ELF_MAG3 'F'
-
-#define ELF_IDENT_COUNT 16
-#define ELF_IDENT_MAG0 0
-#define ELF_IDENT_MAG1 1
-#define ELF_IDENT_MAG2 2
-#define ELF_IDENT_MAG3 3
-
-#define ELF_IDENT_CLASS 4
-#define ELF_IDENT_CLASS_NONE 0
-#define ELF_IDENT_CLASS_32 1
-#define ELF_IDENT_CLASS_64 2
-
-#define ELF_IDENT_DATA 5
-#define ELF_IDENT_DATA_NONE 0
-#define ELF_IDENT_DATA_LSB 1
-#define ELF_IDENT_DATA_MSB 2
-
-#define ELF_IDENT_VERSION 6
-#define ELF_IDENT_OSABI 7
-#define ELF_IDENT_ABIVERSION 8
-#define ELF_IDENT_PAD 9
-
-#define ELF_ETYPE_NONE 0
-#define ELF_ETYPE_REL 1
-#define ELF_ETYPE_EXEC 2
-#define ELF_ETYPE_DYN 3
-#define ELF_ETYPE_CORE 4
-#define ELF_ETYPE_NUM 5
-
-#define ELF_MACHINE_NONE 0
-#define ELF_MACHINE_SPARC 2
-#define ELF_MACHINE_386 3
-#define ELF_MACHINE_SPARC32PLUS 18
-#define ELF_MACHINE_SPARCV9 43
-#define ELF_MACHINE_AMD64 62
-
-#define ELF_PROGRAM_TYPE_NULL 0
-#define ELF_PROGRAM_TYPE_LOAD 1
-#define ELF_PROGRAM_TYPE_DYNAMIC 2
-#define ELF_PROGRAM_TYPE_INTERP 3
-#define ELF_PROGRAM_TYPE_NOTE 4
-#define ELF_PROGRAM_TYPE_SHLIB 5
-#define ELF_PROGRAM_TYPE_PHDR 6
-#define ELF_PROGRAM_TYPE_TLS 7
-
-#define ELF_PROGRAM_FLAG_X 0x1
-#define ELF_PROGRAM_FLAG_W 0x2
-#define ELF_PROGRAM_FLAG_R 0x4
-
-#define ELF_SECTION_TYPE_NULL 0
-#define ELF_SECTION_TYPE_PROGBITS 1
-#define ELF_SECTION_TYPE_SYMTAB 2
-#define ELF_SECTION_TYPE_STRTAB 3
-#define ELF_SECTION_TYPE_RELA 4
-#define ELF_SECTION_TYPE_HASH 5
-#define ELF_SECTION_TYPE_DYNAMIC 6
-#define ELF_SECTION_TYPE_NOTE 7
-#define ELF_SECTION_TYPE_NOBITS 8
-#define ELF_SECTION_TYPE_REL 9
-#define ELF_SECTION_TYPE_SHLIB 10
-#define ELF_SECTION_TYPE_DYNSYM 11
-#define ELF_SECTION_TYPE_COUNT 12
-
-#define ELF_SECTION_FLAG_WRITE 0x1
-#define ELF_SECTION_FLAG_ALLOC 0x2
-#define ELF_SECTION_FLAG_EXEC 0x3
-#define ELF_SECTION_FLAG_MERGE 0x10
-#define ELF_SECTION_FLAG_STRINGS 0x20
-#define ELF_SECTION_FLAG_INFO_LINK 0x40
-#define ELF_SECTION_FLAG_LINK_ORDER 0x80
-#define ELF_SECTION_FLAG_OS_SPECIAL 0x100
-#define ELF_SECTION_FLAG_GROUP 0x200
-#define ELF_SECTION_FLAG_TLS 0x400
-#define ELF_SECTION_FLAG_COMPRESSED 0x800
-
-#define ELF_BSS ".bss"
-#define ELF_DATA ".data"
-#define ELF_DEBUG ".debug"
-#define ELF_DYNAMIC ".dynamic"
-#define ELF_DYNSTR ".dynstr"
-#define ELF_DYNSYM ".dynsym"
-#define ELF_FINI ".fini"
-#define ELF_GOT ".got"
-#define ELF_HASH ".hash"
-#define ELF_INIT ".init"
-#define ELF_REL_DATA ".rel.data"
-#define ELF_REL_FINI ".rel.fini"
-#define ELF_REL_INIT ".rel.init"
-#define ELF_REL_DYN ".rel.dyn"
-#define ELF_REL_RODATA ".rel.rodata"
-#define ELF_REL_TEXT ".rel.text"
-#define ELF_RODATA ".rodata"
-#define ELF_SHSTRTAB ".shstrtab"
-#define ELF_STRTAB ".strtab"
-#define ELF_SYMTAB ".symtab"
-#define ELF_TEXT ".text"
-
-struct PACKED elf_header {
- u8 ident[ELF_IDENT_COUNT];
- u16 type;
- u16 machine;
- u32 version;
- u32 entry;
- u32 phoff;
- u32 shoff;
- u32 flags;
- u16 ehsize;
- u16 phentsize;
- u16 phnum;
- u16 shentsize;
- u16 shnum;
- u16 shstrndx;
-};
-
-struct PACKED elf_program {
- u32 type;
- u32 offset;
- u32 vaddr;
- u32 paddr;
- u32 filesz;
- u32 memsz;
- u32 flags;
- u32 align;
-};
-
-struct PACKED elf_section {
- u32 name;
- u32 type;
- u32 flags;
- u32 addr;
- u32 offset;
- u32 size;
- u32 link;
- u32 info;
- u32 addralign;
- u32 entsize;
-};
-
-struct PACKED elf_symbol {
- u32 name;
- u32 value;
- u32 size;
- u8 info;
- u8 other;
- u16 shndx;
-};
-
-/**
- * EXT2 numbers/structs
- */
-
-#define EXT2_BOOT 0
-#define EXT2_SUPER 1
-#define EXT2_ROOT 2
-#define EXT2_MAGIC 0x0000EF53
-
-struct ext2_superblock {
- u32 total_inodes;
- u32 total_blocks;
- u32 su_res_blocks; // Superuser reserved
- u32 free_blocks;
- u32 free_inodes;
- u32 superblock_block_num;
- u32 log2_block_size;
- u32 log2_frag_size;
- u32 blocks_per_group;
- u32 frags_per_group;
- u32 inodes_per_group;
- u32 last_mount_time;
- u32 last_write_time;
- u16 mounts_since_fsck;
- u16 max_mounts_since_fsck;
- u16 magic;
- u16 state; // 1 clean; 2 errors
- u16 error_action;
- u16 minor_version;
- u32 last_fsck_time;
- u32 max_time_since_fsck;
- u32 creator_os_id;
- u32 major_version;
- u16 res_block_uid;
- u16 res_block_gid;
-};
-
-struct ext2_bgd {
- u32 block_bitmap;
- u32 inode_bitmap;
- u32 inode_table;
- u16 free_blocks;
- u16 free_inodes;
- u16 used_dirs;
- u16 pad;
- u8 bg_reserved[12];
-};
-
-struct ext2_inode {
- u16 mode;
- u16 uid;
- u32 size;
-
- u32 last_access_time;
- u32 creation_time;
- u32 last_modification_time;
- u32 deletion_time;
-
- u16 gid;
- u16 link_count;
- u32 blocks;
- u32 flags;
- u32 os_specific_val1;
- u32 block[15];
- u32 generation;
-
- u32 reserved1;
- u32 reserved2;
-
- u32 fragment_addr;
- u8 os_specific_val2[12];
-};
-
-#define EXT2_INODE_SIZE (sizeof(struct ext2_inode))
-
-struct ext2_dirent {
- u32 inode_num;
- u16 total_len;
- u8 name_len;
- u8 type_indicator;
- u8 name[];
-};
-
-struct ext2_file {
- struct ext2_inode inode;
- u32 pos;
- u8 block_index;
- u8 *buf;
- u32 curr_block_pos;
-};
-
-/**
- * Memory
- */
-
-static u32 heap = 0x0000c000;
-
-static void *memcpy(void *dest, const void *src, u32 n)
-{
- // Inspired by jgraef at osdev
- u32 num_dwords = n / 4;
- u32 num_bytes = n % 4;
- u32 *dest32 = (u32 *)dest;
- const u32 *src32 = (const u32 *)src;
- u8 *dest8 = ((u8 *)dest) + num_dwords * 4;
- const u8 *src8 = ((const u8 *)src) + num_dwords * 4;
-
- __asm__ volatile("rep movsl\n"
- : "=S"(src32), "=D"(dest32), "=c"(num_dwords)
- : "S"(src32), "D"(dest32), "c"(num_dwords)
- : "memory");
-
- for (u32 i = 0; i < num_bytes; i++)
- dest8[i] = src8[i];
-
- return dest;
-}
-
-static void *memset(void *dest, u32 val, u32 n)
-{
- // Inspired by jgraef at osdev
- u32 uval = val;
- u32 num_dwords = n / 4;
- u32 num_bytes = n % 4;
- u32 *dest32 = (u32 *)dest;
- u8 *dest8 = ((u8 *)dest) + num_dwords * 4;
- u8 val8 = (u8)val;
- u32 val32 = uval | (uval << 8) | (uval << 16) | (uval << 24);
-
- __asm__ volatile("rep stosl\n"
- : "=D"(dest32), "=c"(num_dwords)
- : "D"(dest32), "c"(num_dwords), "a"(val32)
- : "memory");
-
- for (u32 i = 0; i < num_bytes; i++)
- dest8[i] = val8;
-
- return dest;
-}
-
-static void *malloc(u32 size)
-{
- return (u32 *)(heap += size);
-}
-
-static void *zalloc(u32 size)
-{
- void *ret = malloc(size);
- memset(ret, 0, size);
- return ret;
-}
-
-static void free(void *ptr)
-{
- (void)ptr;
-}
-
-/**
- * String
- */
-
-static u32 strlen(const char *str)
-{
- const char *s = str;
- while (*s)
- s++;
- return s - str;
-}
-
-static s32 strncmp(const char *s1, const char *s2, u32 n)
-{
- const u8 *c1 = (const u8 *)s1;
- const u8 *c2 = (const u8 *)s2;
- u8 ch;
- int d = 0;
-
- while (n--) {
- d = (int)(ch = *c1++) - (int)*c2++;
- if (d || !ch)
- break;
- }
-
- return d;
-}
-
-static char *strdup(const char *s)
-{
- int l = strlen(s) + 1;
- char *d = malloc(l);
-
- memcpy(d, s, l);
-
- return d;
-}
-
-/**
- * CPU IO
- */
-
-static u8 inb(u16 port)
-{
- u8 value;
- __asm__ volatile("inb %1, %0" : "=a"(value) : "Nd"(port));
- return value;
-}
-
-static u16 inw(u16 port)
-{
- u16 value;
- __asm__ volatile("inw %1, %0" : "=a"(value) : "Nd"(port));
- return value;
-}
-
-static void outb(u16 port, u8 data)
-{
- __asm__ volatile("outb %0, %1" ::"a"(data), "Nd"(port));
-}
-
-/**
- * Serial
- */
-
-static void serial_install(void)
-{
- outb(0x3f8 + 1, 0x00);
- outb(0x3f8 + 3, 0x80);
- outb(0x3f8 + 0, 0x03);
- outb(0x3f8 + 1, 0x00);
- outb(0x3f8 + 3, 0x03);
- outb(0x3f8 + 2, 0xC7);
- outb(0x3f8 + 4, 0x0B);
-}
-
-static int is_transmit_empty(void)
-{
- return inb(0x3f8 + 5) & 0x20;
-}
-
-static void serial_put(char ch)
-{
- while (is_transmit_empty() == 0)
- ;
- outb(0x3f8, (u8)ch);
-}
-
-static void print(const char *data)
-{
- for (u32 i = 0; i < strlen(data); i++)
- serial_put(data[i]);
-}
-
-/**
- * IDE/ATA
- */
-
-static void ide_delay(u16 io) // 400ns
-{
- for (int i = 0; i < 4; i++)
- inb(io + ATA_REG_ALTSTATUS);
-}
-
-static void ide_poll(u16 io)
-{
- for (int i = 0; i < 4; i++)
- inb(io + ATA_REG_ALTSTATUS);
-
- u8 status;
- do {
- status = inb(io + ATA_REG_STATUS);
- } while (status & ATA_SR_BSY);
-
- do {
- status = inb(io + ATA_REG_STATUS);
- /* assert(!(status & ATA_SR_ERR)) */
- } while (!(status & ATA_SR_DRQ));
-}
-
-static u8 ata_read_one(u8 *buf, u32 lba, u8 drive)
-{
- u16 io = (drive & ATA_PRIMARY << 1) == ATA_PRIMARY ? ATA_PRIMARY_IO : ATA_SECONDARY_IO;
- drive = (drive & ATA_SLAVE) == ATA_SLAVE ? ATA_SLAVE : ATA_MASTER;
- u8 cmd = drive == ATA_MASTER ? 0xe0 : 0xf0;
- outb(io + ATA_REG_HDDEVSEL, (cmd | (u8)((lba >> 24 & 0x0f))));
- outb(io + 1, 0x00);
- outb(io + ATA_REG_SECCOUNT0, 1);
- outb(io + ATA_REG_LBA0, (u8)lba);
- outb(io + ATA_REG_LBA1, (u8)(lba >> 8));
- outb(io + ATA_REG_LBA2, (u8)(lba >> 16));
- outb(io + ATA_REG_COMMAND, ATA_CMD_READ_PIO);
- ide_poll(io);
-
- for (int i = 0; i < BLOCK_COUNT; i++) {
- u16 data = inw(io + ATA_REG_DATA);
- *(u16 *)(buf + i * 2) = data;
- }
- ide_delay(io);
- return 1;
-}
-
-static u32 ata_read(void *buf, u32 lba, u32 sector_count, u8 drive)
-{
- u8 *b = buf; // I love bytes, yk
- for (u32 i = 0; i < sector_count; i++) {
- ata_read_one(b, lba + i, drive);
- b += SECTOR_SIZE;
- }
- return sector_count;
-}
-
-/**
- * EXT2
- */
-
-static void *buffer_read(u32 block, u8 drive)
-{
- void *buf = zalloc(BLOCK_SIZE);
- ata_read(buf, block * SECTOR_COUNT, SECTOR_COUNT, drive);
- return buf;
-}
-
-static struct ext2_superblock *get_superblock(u8 drive)
-{
- struct ext2_superblock *sb = buffer_read(EXT2_SUPER, drive);
-
- assert(sb->magic == EXT2_MAGIC);
- return sb;
-}
-
-static struct ext2_bgd *get_bgd(u8 drive)
-{
- return buffer_read(EXT2_SUPER + 1, drive);
-}
-
-static struct ext2_inode *get_inode(u32 i, struct ext2_inode *in_buf, u8 drive)
-{
- struct ext2_superblock *s = get_superblock(drive);
- assert(s);
- struct ext2_bgd *b = get_bgd(drive);
- assert(b);
-
- u32 block_group = (i - 1) / s->inodes_per_group;
- u32 index = (i - 1) % s->inodes_per_group;
- u32 block = (index * EXT2_INODE_SIZE) / BLOCK_SIZE;
- b += block_group;
-
- u32 *buf = buffer_read(b->inode_table + block, drive);
- struct ext2_inode *in =
- (struct ext2_inode *)((u32)buf +
- (index % (BLOCK_SIZE / EXT2_INODE_SIZE)) * EXT2_INODE_SIZE);
-
- memcpy(in_buf, in, sizeof(*in_buf));
- free(buf);
- free(s);
- free(b - block_group);
-
- return in_buf;
-}
-
-static u32 find_inode(const char *name, u32 dir_inode, u8 drive)
-{
- if (!dir_inode)
- return (unsigned)-1;
-
- struct ext2_inode i = { 0 };
- get_inode(dir_inode, &i, drive);
-
- char *buf = malloc(BLOCK_SIZE * i.blocks / 2);
- memset(buf, 0, BLOCK_SIZE * i.blocks / 2);
-
- for (u32 q = 0; q < i.blocks / 2; q++) {
- char *data = buffer_read(i.block[q], drive);
- memcpy((u32 *)((u32)buf + q * BLOCK_SIZE), data, BLOCK_SIZE);
- free(data);
- }
-
- struct ext2_dirent *d = (struct ext2_dirent *)buf;
-
- u32 sum = 0;
- do {
- // Calculate the 4byte aligned size of each entry
- sum += d->total_len;
- if (strlen(name) == d->name_len &&
- strncmp((void *)d->name, name, d->name_len) == 0) {
- free(buf);
- return d->inode_num;
- }
- d = (struct ext2_dirent *)((u32)d + d->total_len);
-
- } while (sum < (1024 * i.blocks / 2));
- free(buf);
- return (unsigned)-1;
-}
-
-static u32 read_indirect(u32 indirect, u32 block_num, u8 drive)
-{
- void *data = buffer_read(indirect, drive);
- u32 ind = *(u32 *)((u32)data + block_num * sizeof(u32));
- free(data);
- return ind;
-}
-
-static s32 read_inode(struct ext2_inode *in, void *buf, u32 offset, u32 count, u8 drive)
-{
- if (!in || !buf)
- return -1;
-
- if (in->size == 0)
- return 0;
-
- u32 num_blocks = in->blocks / (BLOCK_SIZE / SECTOR_SIZE) + 1;
-
- if (!num_blocks)
- return -1;
-
- u32 first_block = offset / BLOCK_SIZE;
- u32 last_block = (offset + count) / BLOCK_SIZE;
- if (last_block >= num_blocks)
- last_block = num_blocks - 1;
- u32 first_block_offset = offset % BLOCK_SIZE;
-
- u32 remaining = MIN(count, in->size - offset);
- u32 copied = 0;
-
- u32 indirect = 0;
- u32 blocknum = 0;
-
- // TODO: Support triply indirect pointers
- for (u32 i = first_block; i <= last_block; i++) {
- if (i < 12) {
- blocknum = in->block[i];
- } else if (i < BLOCK_COUNT + 12) {
- indirect = in->block[12];
- blocknum = read_indirect(indirect, i - 12, drive);
- } else {
- indirect = in->block[13];
- blocknum = read_indirect(indirect, (i - (BLOCK_COUNT + 12)) / BLOCK_COUNT,
- drive);
- blocknum = read_indirect(blocknum, (i - (BLOCK_COUNT + 12)) % BLOCK_COUNT,
- drive);
- }
-
- char *data = buffer_read(blocknum, drive);
- u32 block_offset = (i == first_block) ? first_block_offset : 0;
- u32 byte_count = MIN(BLOCK_SIZE - block_offset, remaining);
-
- memcpy((u8 *)buf + copied, data + block_offset, byte_count);
-
- copied += byte_count;
- remaining -= byte_count;
-
- free(data);
- }
-
- return copied;
-}
-
-static struct ext2_inode *find_inode_by_path(const char *path, struct ext2_inode *in_buf, u8 drive)
-{
- char *path_cp = strdup(path);
- char *init = path_cp; // For freeing
-
- if (path_cp[0] != '/') {
- free(init);
- return NULL;
- }
-
- path_cp++;
- u32 current_inode = EXT2_ROOT;
-
- u32 i = 0;
- while (1) {
- for (i = 0; path_cp[i] != '/' && path_cp[i] != '\0'; i++)
- ;
-
- if (path_cp[i] == '\0')
- break;
-
- path_cp[i] = '\0';
- current_inode = find_inode(path_cp, current_inode, drive);
- path_cp[i] = '/';
-
- if (current_inode == 0) {
- free(init);
- return NULL;
- }
-
- path_cp += i + 1;
- }
-
- u32 inode = find_inode(path_cp, current_inode, drive);
- free(init);
- if ((signed)inode <= 0)
- return NULL;
-
- return get_inode(inode, in_buf, drive);
-}
-
-static s32 read(const char *path, void *buf, u32 offset, u32 count, u8 drive)
-{
- struct ext2_inode in = { 0 };
- if (find_inode_by_path(path, &in, drive) == &in) {
- return read_inode(&in, buf, offset, count, drive);
- } else {
- print("Couldn't find kernel!\n");
- return -1;
- }
-}
-
-/**
- * ELF
- */
-
-static s32 elf_load(const char *path, u8 drive)
-{
- struct elf_header header = { 0 };
- s32 rd = read(path, &header, 0, sizeof(header), drive);
- if (rd < 0)
- return rd;
- if (rd != sizeof(header))
- return -1;
-
- // Valid?
- u8 *magic = header.ident;
- u8 valid_magic = magic[ELF_IDENT_MAG0] == ELF_MAG0 && magic[ELF_IDENT_MAG1] == ELF_MAG1 &&
- magic[ELF_IDENT_MAG2] == ELF_MAG2 && magic[ELF_IDENT_MAG3] == ELF_MAG3 &&
- magic[ELF_IDENT_CLASS] == ELF_IDENT_CLASS_32 &&
- magic[ELF_IDENT_DATA] == ELF_IDENT_DATA_LSB;
- if (!valid_magic || (header.type != ELF_ETYPE_REL && header.type != ELF_ETYPE_EXEC) ||
- header.version != 1 || header.machine != ELF_MACHINE_386)
- return -1;
-
- // Loop through programs
- for (u32 i = 0; i < header.phnum; i++) {
- struct elf_program program = { 0 };
-
- if (read(path, &program, header.phoff + header.phentsize * i, sizeof(program),
- drive) != sizeof(program))
- return -1;
-
- if (program.type == ELF_PROGRAM_TYPE_INTERP)
- return -1;
-
- if (program.vaddr == 0 || program.type != ELF_PROGRAM_TYPE_LOAD)
- continue;
-
- if ((u32)read(path, (void *)program.vaddr, program.offset, program.filesz, drive) !=
- program.filesz)
- return -1;
- }
-
- // Find section string table
- struct elf_section section_strings = { 0 };
- if (read(path, &section_strings, header.shoff + header.shentsize * header.shstrndx,
- sizeof(section_strings), drive) != sizeof(section_strings))
- return -1;
-
- if (section_strings.type != ELF_SECTION_TYPE_STRTAB)
- return -1;
-
- return header.entry;
-}
-
-/**
- * Let's go!
- */
-
-struct boot_info {
- u32 vid;
- u32 mem;
- u32 tss;
- u32 drive;
-};
-
-int main(struct boot_info *boot)
-{
- serial_install();
- print("Loaded bootloader!\n");
-
- assert(boot->drive);
-
- s32 elf = elf_load("/apps/kernel/exec", boot->drive);
- assert(elf > 0);
-
- void (*kernel)(void *);
- *(void **)(&kernel) = (void *)elf;
-
- print("Loaded kernel!\n");
- kernel(boot);
-
- print("WTF, kernel returned!\n");
-
- while (1)
- ;
-
- return 0;
-}