diff options
Diffstat (limited to 'grub-core/lib/i386/relocator.c')
| -rw-r--r-- | grub-core/lib/i386/relocator.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/grub-core/lib/i386/relocator.c b/grub-core/lib/i386/relocator.c new file mode 100644 index 0000000..1bc4240 --- /dev/null +++ b/grub-core/lib/i386/relocator.c @@ -0,0 +1,270 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2009 Free Software Foundation, Inc. + * + * GRUB 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 3 of the License, or + * (at your option) any later version. + * + * GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <grub/mm.h> +#include <grub/misc.h> + +#include <grub/types.h> +#include <grub/err.h> +#include <grub/term.h> + +#include <grub/i386/relocator.h> +#include <grub/relocator_private.h> + +extern grub_uint8_t grub_relocator_forward_start; +extern grub_uint8_t grub_relocator_forward_end; +extern grub_uint8_t grub_relocator_backward_start; +extern grub_uint8_t grub_relocator_backward_end; + +extern void *grub_relocator_backward_dest; +extern void *grub_relocator_backward_src; +extern grub_size_t grub_relocator_backward_chunk_size; + +extern void *grub_relocator_forward_dest; +extern void *grub_relocator_forward_src; +extern grub_size_t grub_relocator_forward_chunk_size; + +extern grub_uint8_t grub_relocator16_start; +extern grub_uint8_t grub_relocator16_end; +extern grub_uint16_t grub_relocator16_cs; +extern grub_uint16_t grub_relocator16_ip; +extern grub_uint16_t grub_relocator16_ds; +extern grub_uint16_t grub_relocator16_es; +extern grub_uint16_t grub_relocator16_fs; +extern grub_uint16_t grub_relocator16_gs; +extern grub_uint16_t grub_relocator16_ss; +extern grub_uint16_t grub_relocator16_sp; +extern grub_uint32_t grub_relocator16_edx; + +extern grub_uint8_t grub_relocator32_start; +extern grub_uint8_t grub_relocator32_end; +extern grub_uint32_t grub_relocator32_eax; +extern grub_uint32_t grub_relocator32_ebx; +extern grub_uint32_t grub_relocator32_ecx; +extern grub_uint32_t grub_relocator32_edx; +extern grub_uint32_t grub_relocator32_eip; +extern grub_uint32_t grub_relocator32_esp; +extern grub_uint32_t grub_relocator32_ebp; +extern grub_uint32_t grub_relocator32_esi; +extern grub_uint32_t grub_relocator32_edi; + +extern grub_uint8_t grub_relocator64_start; +extern grub_uint8_t grub_relocator64_end; +extern grub_uint64_t grub_relocator64_rax; +extern grub_uint64_t grub_relocator64_rbx; +extern grub_uint64_t grub_relocator64_rcx; +extern grub_uint64_t grub_relocator64_rdx; +extern grub_uint64_t grub_relocator64_rip; +extern grub_uint64_t grub_relocator64_rip_addr; +extern grub_uint64_t grub_relocator64_rsp; +extern grub_uint64_t grub_relocator64_rsi; +extern grub_addr_t grub_relocator64_cr3; + +#define RELOCATOR_SIZEOF(x) (&grub_relocator##x##_end - &grub_relocator##x##_start) + +grub_size_t grub_relocator_align = 1; +grub_size_t grub_relocator_forward_size; +grub_size_t grub_relocator_backward_size; +#ifdef __x86_64__ +grub_size_t grub_relocator_jumper_size = 12; +#else +grub_size_t grub_relocator_jumper_size = 7; +#endif + +void +grub_cpu_relocator_init (void) +{ + grub_relocator_forward_size = RELOCATOR_SIZEOF(_forward); + grub_relocator_backward_size = RELOCATOR_SIZEOF(_backward); +} + +void +grub_cpu_relocator_jumper (void *rels, grub_addr_t addr) +{ + grub_uint8_t *ptr; + ptr = rels; +#ifdef __x86_64__ + /* movq imm64, %rax (for relocator) */ + *(grub_uint8_t *) ptr = 0x48; + ptr++; + *(grub_uint8_t *) ptr = 0xb8; + ptr++; + *(grub_uint64_t *) ptr = addr; + ptr += sizeof (grub_uint64_t); +#else + /* movl imm32, %eax (for relocator) */ + *(grub_uint8_t *) ptr = 0xb8; + ptr++; + *(grub_uint32_t *) ptr = addr; + ptr += sizeof (grub_uint32_t); +#endif + /* jmp $eax/$rax */ + *(grub_uint8_t *) ptr = 0xff; + ptr++; + *(grub_uint8_t *) ptr = 0xe0; + ptr++; +} + +void +grub_cpu_relocator_backward (void *ptr, void *src, void *dest, + grub_size_t size) +{ + grub_relocator_backward_dest = dest; + grub_relocator_backward_src = src; + grub_relocator_backward_chunk_size = size; + + grub_memmove (ptr, + &grub_relocator_backward_start, + RELOCATOR_SIZEOF (_backward)); +} + +void +grub_cpu_relocator_forward (void *ptr, void *src, void *dest, + grub_size_t size) +{ + grub_relocator_forward_dest = dest; + grub_relocator_forward_src = src; + grub_relocator_forward_chunk_size = size; + + grub_memmove (ptr, + &grub_relocator_forward_start, + RELOCATOR_SIZEOF (_forward)); +} + +grub_err_t +grub_relocator32_boot (struct grub_relocator *rel, + struct grub_relocator32_state state) +{ + grub_err_t err; + void *relst; + grub_relocator_chunk_t ch; + + err = grub_relocator_alloc_chunk_align (rel, &ch, 0, + (0xffffffff - RELOCATOR_SIZEOF (32)) + + 1, RELOCATOR_SIZEOF (32), 16, + GRUB_RELOCATOR_PREFERENCE_NONE); + if (err) + return err; + + grub_relocator32_eax = state.eax; + grub_relocator32_ebx = state.ebx; + grub_relocator32_ecx = state.ecx; + grub_relocator32_edx = state.edx; + grub_relocator32_eip = state.eip; + grub_relocator32_esp = state.esp; + grub_relocator32_ebp = state.ebp; + grub_relocator32_esi = state.esi; + grub_relocator32_edi = state.edi; + + grub_memmove (get_virtual_current_address (ch), &grub_relocator32_start, + RELOCATOR_SIZEOF (32)); + + err = grub_relocator_prepare_relocs (rel, get_physical_target_address (ch), + &relst, NULL); + if (err) + return err; + + asm volatile ("cli"); + ((void (*) (void)) relst) (); + + /* Not reached. */ + return GRUB_ERR_NONE; +} + +grub_err_t +grub_relocator16_boot (struct grub_relocator *rel, + struct grub_relocator16_state state) +{ + grub_err_t err; + void *relst; + grub_relocator_chunk_t ch; + + err = grub_relocator_alloc_chunk_align (rel, &ch, 0, + 0xa0000 - RELOCATOR_SIZEOF (16), + RELOCATOR_SIZEOF (16), 16, + GRUB_RELOCATOR_PREFERENCE_NONE); + if (err) + return err; + + grub_relocator16_cs = state.cs; + grub_relocator16_ip = state.ip; + + grub_relocator16_ds = state.ds; + grub_relocator16_es = state.es; + grub_relocator16_fs = state.fs; + grub_relocator16_gs = state.gs; + + grub_relocator16_ss = state.ss; + grub_relocator16_sp = state.sp; + + grub_relocator16_edx = state.edx; + + grub_memmove (get_virtual_current_address (ch), &grub_relocator16_start, + RELOCATOR_SIZEOF (16)); + + err = grub_relocator_prepare_relocs (rel, get_physical_target_address (ch), + &relst, NULL); + if (err) + return err; + + asm volatile ("cli"); + ((void (*) (void)) relst) (); + + /* Not reached. */ + return GRUB_ERR_NONE; +} + +grub_err_t +grub_relocator64_boot (struct grub_relocator *rel, + struct grub_relocator64_state state, + grub_addr_t min_addr, grub_addr_t max_addr) +{ + grub_err_t err; + void *relst; + grub_relocator_chunk_t ch; + + err = grub_relocator_alloc_chunk_align (rel, &ch, min_addr, + max_addr - RELOCATOR_SIZEOF (64), + RELOCATOR_SIZEOF (64), 16, + GRUB_RELOCATOR_PREFERENCE_NONE); + if (err) + return err; + + grub_relocator64_rax = state.rax; + grub_relocator64_rbx = state.rbx; + grub_relocator64_rcx = state.rcx; + grub_relocator64_rdx = state.rdx; + grub_relocator64_rip = state.rip; + grub_relocator64_rsp = state.rsp; + grub_relocator64_rsi = state.rsi; + grub_relocator64_cr3 = state.cr3; + + grub_memmove (get_virtual_current_address (ch), &grub_relocator64_start, + RELOCATOR_SIZEOF (64)); + + err = grub_relocator_prepare_relocs (rel, get_physical_target_address (ch), + &relst, NULL); + if (err) + return err; + + asm volatile ("cli"); + ((void (*) (void)) relst) (); + + /* Not reached. */ + return GRUB_ERR_NONE; +} |