blacktop/ipsw v3.1.600

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int update_lockdown_mode_state(void) {
    // Stack canary setup
    uintptr_t stack_canary = *__stack_chk_guard;

    // Prepare sysctlbyname arguments
    const char *name = "security.mac.lockdown_mode_state";
    int value = 0;
    size_t value_len = 8;
    int result = sysctlbyname(name, &value, &value_len, NULL, 0);

    // If sysctlbyname succeeded and value == 1, set byte to 1, else 0
    unsigned char lockdown_mode = (result == 0 && value == 1) ? 1 : 0;
    *(volatile unsigned char *)(&LockdownMode) = lockdown_mode;

    // Stack canary check
    if (stack_canary != *__stack_chk_guard)
        __stack_chk_fail();

    return 0;
}