參考資訊:
https://stackoverflow.com/questions/41690592/what-does-gs0x10-do-in-assembler
https://chromium.googlesource.com/chromiumos/docs/+/HEAD/constants/syscalls.md
https://reverseengineering.stackexchange.com/questions/2869/how-to-use-sysenter-under-linux
System Call
NR | syscall name | eax | arg0(ebx) | arg1(ecx) | arg2(edx) |
---|---|---|---|---|---|
1 | exit | 1 | int error_code | ||
4 | write | 4 | unsigned int fd | const char *buf | size_t count |
main.s
global main section .data msg db "hello, world!", 10 len equ $ - msg section .text main: mov eax, 4 mov ebx, 1 mov ecx, msg mov edx, len call [gs:0x10] mov eax, 1 mov ebx, 0 call [gs:0x10]
編譯、執行
$ nasm -f elf32 main.s $ i686-linux-gnu-gcc main.o -o main -static $ qemu-i386 ./main hello, world!