posix-uefi/uefi/crt_x86_64.c
2021-02-01 01:09:23 +01:00

286 lines
8.1 KiB
C

/*
* crt_x86_64.c
*
* Copyright (C) 2021 bzt (bztsrc@gitlab)
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* This file is part of the POSIX-UEFI package.
* @brief C runtime, bootstraps an EFI application to call standard main()
*
*/
#include <uefi.h>
#include <uefielf.h>
/* this is implemented by the application */
extern int main(int argc, wchar_t **argv);
/* globals to store system table pointers */
efi_handle_t IM = NULL;
efi_system_table_t *ST = NULL;
efi_boot_services_t *BS = NULL;
efi_runtime_services_t *RT = NULL;
efi_loaded_image_protocol_t *LIP = NULL;
/* we only need one .o file, so use inline Assembly here */
void bootstrap()
{
__asm__ __volatile__ (
/* call init in C */
" .align 4;"
" .globl _start;"
"_start:"
" lea ImageBase(%rip), %rdi;"
" lea _DYNAMIC(%rip), %rsi;"
" call uefi_init;"
" ret;"
/*** the following code snipplets are borrowed from gnu-efi ***/
/* setjmp and longjmp */
" .globl setjmp;"
"setjmp:"
" pop %rsi;"
" movq %rbx,0x00(%rdi);"
" movq %rsp,0x08(%rdi);"
" push %rsi;"
" movq %rbp,0x10(%rdi);"
" movq %r12,0x18(%rdi);"
" movq %r13,0x20(%rdi);"
" movq %r14,0x28(%rdi);"
" movq %r15,0x30(%rdi);"
" movq %rsi,0x38(%rdi);"
" xor %rax,%rax;"
" ret;"
" .globl longjmp;"
"longjmp:"
" movl %esi, %eax;"
" movq 0x00(%rdi), %rbx;"
" movq 0x08(%rdi), %rsp;"
" movq 0x10(%rdi), %rbp;"
" movq 0x18(%rdi), %r12;"
" movq 0x20(%rdi), %r13;"
" movq 0x28(%rdi), %r14;"
" movq 0x30(%rdi), %r15;"
" xor %rdx,%rdx;"
" mov $1,%rcx;"
" cmp %rax,%rdx;"
" cmove %rcx,%rax;"
" jmp *0x38(%rdi);"
/* for uefi_call_wrapper */
" .globl uefi_call0;"
"uefi_call0:"
" subq $40, %rsp;"
" call *%rdi;"
" addq $40, %rsp;"
" ret;"
" .globl uefi_call1;"
"uefi_call1:"
" subq $40, %rsp;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $40, %rsp;"
" ret;"
" .globl uefi_call2;"
"uefi_call2:"
" subq $40, %rsp;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $40, %rsp;"
" ret;"
" .globl uefi_call3;"
"uefi_call3:"
" subq $40, %rsp;"
" mov %rcx, %r8;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $40, %rsp;"
" ret;"
" .globl uefi_call4;"
"uefi_call4:"
" subq $40, %rsp;"
" mov %r8, %r9;"
" mov %rcx, %r8;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $40, %rsp;"
" ret;"
" .globl uefi_call5;"
"uefi_call5:"
" subq $40, %rsp;"
" mov %r9, 32(%rsp);"
" mov %r8, %r9;"
" mov %rcx, %r8;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $40, %rsp;"
" ret;"
" .globl uefi_call6;"
"uefi_call6:"
" subq $56, %rsp;"
" mov 56+8(%rsp), %rax;"
" mov %rax, 40(%rsp);"
" mov %r9, 32(%rsp);"
" mov %r8, %r9;"
" mov %rcx, %r8;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $56, %rsp;"
" ret;"
" .globl uefi_call7;"
"uefi_call7:"
" subq $56, %rsp;"
" mov 56+16(%rsp), %rax;"
" mov %rax, 48(%rsp);"
" mov 56+8(%rsp), %rax;"
" mov %rax, 40(%rsp);"
" mov %r9, 32(%rsp);"
" mov %r8, %r9;"
" mov %rcx, %r8;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $56, %rsp;"
" ret;"
" .globl uefi_call8;"
"uefi_call8:"
" subq $72, %rsp;"
" mov 72+24(%rsp), %rax;"
" mov %rax, 56(%rsp);"
" mov 72+16(%rsp), %rax;"
" mov %rax, 48(%rsp);"
" mov 72+8(%rsp), %rax;"
" mov %rax, 40(%rsp);"
" mov %r9, 32(%rsp);"
" mov %r8, %r9;"
" mov %rcx, %r8;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $72, %rsp;"
" ret;"
" .globl uefi_call9;"
"uefi_call9:"
" subq $72, %rsp;"
" mov 72+32(%rsp), %rax;"
" mov %rax, 64(%rsp);"
" mov 72+24(%rsp), %rax;"
" mov %rax, 56(%rsp);"
" mov 72+16(%rsp), %rax;"
" mov %rax, 48(%rsp);"
" mov 72+8(%rsp), %rax;"
" mov %rax, 40(%rsp);"
" mov %r9, 32(%rsp);"
" mov %r8, %r9;"
" mov %rcx, %r8;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $72, %rsp;"
" ret;"
" .globl uefi_call10;"
"uefi_call10:"
" subq $88, %rsp;"
" mov 88+40(%rsp), %rax;"
" mov %rax, 72(%rsp);"
" mov 88+32(%rsp), %rax;"
" mov %rax, 64(%rsp);"
" mov 88+24(%rsp), %rax;"
" mov %rax, 56(%rsp);"
" mov 88+16(%rsp), %rax;"
" mov %rax, 48(%rsp);"
" mov 88+8(%rsp), %rax;"
" mov %rax, 40(%rsp);"
" mov %r9, 32(%rsp);"
" mov %r8, %r9;"
" mov %rcx, %r8;"
" mov %rsi, %rcx;"
" call *%rdi;"
" addq $88, %rsp;"
" ret;"
);
}
/**
* Initialize POSIX-UEFI and call teh application's main() function
*/
int uefi_init (efi_handle_t image, efi_system_table_t *systab, uintptr_t ldbase, Elf64_Dyn *dyn) {
long relsz = 0, relent = 0;
Elf64_Rel *rel = 0;
uintptr_t *addr;
efi_guid_t shpGuid = EFI_SHELL_PARAMETERS_PROTOCOL_GUID;
efi_shell_parameters_protocol_t *shp = NULL;
efi_guid_t shiGuid = SHELL_INTERFACE_PROTOCOL_GUID;
efi_shell_interface_protocol_t *shi = NULL;
efi_guid_t lipGuid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
efi_status_t status;
int i, argc = 0;
wchar_t **argv = NULL;
/* handle relocations */
for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
switch (dyn[i].d_tag) {
case DT_RELA: rel = (Elf64_Rel*)((unsigned long)dyn[i].d_un.d_ptr + ldbase); break;
case DT_RELASZ: relsz = dyn[i].d_un.d_val; break;
case DT_RELAENT: relent = dyn[i].d_un.d_val; break;
default: break;
}
}
if (rel && relent) {
while (relsz > 0) {
if(ELF64_R_TYPE (rel->r_info) == R_X86_64_RELATIVE)
{ addr = (unsigned long *)(ldbase + rel->r_offset); *addr += ldbase; break; }
rel = (Elf64_Rel*) ((char *) rel + relent);
relsz -= relent;
}
}
/* save EFI pointers and loaded image into globals */
IM = image;
ST = systab;
BS = systab->BootServices;
RT = systab->RuntimeServices;
uefi_call_wrapper(BS->HandleProtocol, 3, image, &lipGuid, (void **) &LIP);
/* get command line arguments */
status = uefi_call_wrapper(BS->OpenProtocol, 6, image, &shpGuid, &shp, image, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
if(!EFI_ERROR(status) && shp) { argc = shp->Argc; argv = shp->Argv; }
else {
/* if shell 2.0 failed, fallback to shell 1.0 interface */
status = uefi_call_wrapper(BS->OpenProtocol, 6, image, &shiGuid, &shi, image, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
if(!EFI_ERROR(status) && shi) { argc = shi->Argc; argv = shi->Argv; }
}
/* call main */
return main(argc, argv);
}
/**
* Exit Boot Services
*/
boolean_t uefi_exit_bs()
{
efi_status_t status;
efi_memory_descriptor_t *memory_map = NULL;
uintn_t cnt = 3, memory_map_size=0, map_key=0, desc_size=0;
while(cnt--) {
status = uefi_call_wrapper(BS->GetMemoryMap, 5, &memory_map_size, memory_map, &map_key, &desc_size, NULL);
if (status!=EFI_BUFFER_TOO_SMALL) break;
status = uefi_call_wrapper(BS->ExitBootServices, 2, IM, map_key);
if(!EFI_ERROR(status)) return 1;
}
return 0;
}