To build a structure in Gforth to hold the x86 machine code and replace the int 0x80
system call with a RET
instruction. Using Gforth's ability to handle low-level memory operations and execute machine code, the goal is to build a structure to hold pre compiled machine code and execute with in Forth, Here is an ideal way to approach this task:
- Define a structure to hold the machine code: This structure will be a memory buffer that stores the extracted machine code.
- Substitute
int 0x80
withRET
: Modify the machine code to replace theint 0x80
(opcodecd 80
) withRET
(opcodec3
). - Create a mechanism to call this code: Use Gforth's ability to execute arbitrary machine code by defining a Forth word that jumps to the machine code buffer.