46 lines
869 B
C
46 lines
869 B
C
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#include <stdint.h>
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#include <stddef.h>
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#include <debugging.h>
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#include <kernel/tty.h>
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#include <kernel/gdt.h>
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void run_program(uint8_t* program, size_t length)
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{
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uint8_t* userland_code = (uint8_t*) 0x00800004;
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for (size_t i = 0; i < length; i++) {
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userland_code[i] = program[i];
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}
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tss.ss0 = 0x10;
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asm("sti");
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asm("int 0x80");
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asm("mov %0, esp" : "=r" (tss.esp0));
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// Generates segfault
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// asm("mov esp, %0" : "=r" (tss.esp0));
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asm("mov ax, 0x23 # Load registers with the correct GDT segments values");
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asm("mov ds, ax");
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asm("mov es, ax");
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asm("mov fs, ax");
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asm("mov gs, ax");
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asm("push 0x23");
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asm("push 0x00c00100");
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asm("pushfd");
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asm("pop eax");
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asm("or eax, 0x200");
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asm("push eax");
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asm("push 0x1b");
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asm("push 0x00800000");
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asm("iret");
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asm("int 0x21");
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}
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