# Pastebin 2IqhTzHR
#include <sys/mman.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <mach/mach.h>
#include <pthread.h>
#include <libkern/OSCacheControl.h>

int foo(int a)
{
    return a;
}

#define CHECK(kt, s) if (kt) { printf(s); abort(); }

int x_main()
{
    size_t page_size = 16384;
    vm_address_t page, x_page;
    vm_prot_t cur, max;
    kern_return_t kt;
    unsigned char *writable, *foo_dis;

    kt = vm_allocate(mach_task_self(), &page, page_size * 10, VM_FLAGS_ANYWHERE);
    CHECK(kt != KERN_SUCCESS, "error calling vm_allocate\n")

    x_page = page;
    kt = vm_remap(mach_task_self(), &x_page, page_size * 10, 0x0, VM_FLAGS_OVERWRITE,
        mach_task_self(), page, FALSE, &cur, &max, VM_INHERIT_SHARE);
    CHECK(kt != KERN_SUCCESS, "error calling remap\n")
    //CHECK(!(cur & VM_PROT_EXECUTE), "not executable\n")

    writable = (unsigned char*)page;
    *writable = 192;
    *(writable + 1) = 3;
    *(writable + 2) = 95;
    *(writable + 3) = 214;

    kt = vm_protect(mach_task_self(), page, page_size * 10, FALSE, VM_PROT_READ | VM_PROT_EXECUTE);
    CHECK(kt != KERN_SUCCESS, "error calling mprotect\n")

    foo_dis = writable;
    printf("%d %d %d %d\n", *foo_dis, *(foo_dis + 1), *(foo_dis + 2), *(foo_dis + 3));
    printf("%d\n", ((int (*)(int))(foo_dis))(3));
    /*void *writable, *code;
    
    printf("Page size: %ld\n", page_size);
    writable = mmap(0, page_size * 10, PROT_READ | PROT_WRITE,
                     MAP_ANON | MAP_PRIVATE, -1, 0);
    printf("writable: %p\n", writable);
    code = mmap(writable, page_size * 10, PROT_READ | PROT_EXEC, MAP_ANON | MAP_PRIVATE, -1, 0);
    *(long*)(writable) = 1234;
    printf("%ld\n", *(long*)(code));*/
    /**(unsigned char*)(writable) = 192;
    *((unsigned char*)(writable) + 1) = 3;
    *((unsigned char*)(writable) + 2) = 95;
    *((unsigned char*)(writable) + 3) = 214;
    foo_dis = (unsigned char*)foo;
    //printf("code: %p\n", code);*/
    return 0;
}

int main()
{
    size_t page_size = 16384;
    unsigned char *writable, *foo_dis;

    writable = (unsigned char*)mmap(0, page_size * 10, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_JIT | MAP_ANON | MAP_PRIVATE, -1, 0);
    CHECK(writable == NULL, "error calling mmap\n")

/*    kt = vm_allocate(mach_task_self(), &page, page_size * 10, VM_FLAGS_ANYWHERE);
    CHECK(kt != KERN_SUCCESS, "error calling vm_allocate\n")

    x_page = page;
    kt = vm_remap(mach_task_self(), &x_page, page_size * 10, 0x0, VM_FLAGS_OVERWRITE,
        mach_task_self(), page, FALSE, &cur, &max, VM_INHERIT_SHARE);
    CHECK(kt != KERN_SUCCESS, "error calling remap\n")
    //CHECK(!(cur & VM_PROT_EXECUTE), "not executable\n")*/

    //writable = (unsigned char*)page;
    pthread_jit_write_protect_np(0);
    *writable = 192;
    *(writable + 1) = 3;
    *(writable + 2) = 95;
    *(writable + 3) = 214;
    pthread_jit_write_protect_np(1);
    sys_icache_invalidate(writable, page_size * 10);
    printf("%d\n", ((int (*)(int))(writable))(3));

    /*kt = vm_protect(mach_task_self(), page, page_size * 10, FALSE, VM_PROT_READ | VM_PROT_EXECUTE);
    CHECK(kt != KERN_SUCCESS, "error calling mprotect\n")

    foo_dis = writable;
    printf("%d %d %d %d\n", *foo_dis, *(foo_dis + 1), *(foo_dis + 2), *(foo_dis + 3));
    printf("%d\n", ((int (*)(int))(foo_dis))(3));*/
    /*void *writable, *code;
    
    printf("Page size: %ld\n", page_size);
    writable = mmap(0, page_size * 10, PROT_READ | PROT_WRITE,
                     MAP_ANON | MAP_PRIVATE, -1, 0);
    printf("writable: %p\n", writable);
    code = mmap(writable, page_size * 10, PROT_READ | PROT_EXEC, MAP_ANON | MAP_PRIVATE, -1, 0);
    *(long*)(writable) = 1234;
    printf("%ld\n", *(long*)(code));*/
    /**(unsigned char*)(writable) = 192;
    *((unsigned char*)(writable) + 1) = 3;
    *((unsigned char*)(writable) + 2) = 95;
    *((unsigned char*)(writable) + 3) = 214;
    foo_dis = (unsigned char*)foo;
    //printf("code: %p\n", code);*/
    return 0;
}