kbfuck.m

//  kbfuck.m
//
//  randomly remaps all keys on keyboard in macOS

#import <Foundation/Foundation.h>
#import <IOKit/hidsystem/IOHIDEventSystemClient.h>
#import <IOKit/hidsystem/IOHIDServiceClient.h>
#import <IOKit/hid/IOHIDUsageTables.h>

int main(int argc, const char * argv[]) {
    
    IOHIDEventSystemClientRef system;
    CFArrayRef services;
    
    NSMutableArray *map = [[NSMutableArray alloc] init];
    
    for (int i = 0; i < 100; i++) {
        uint64_t code1 = (arc4random_uniform(0x6f) + 0x4) | 0x700000000;
        uint64_t code2 = (arc4random_uniform(0x6f) + 0x4) | 0x700000000;
        NSDictionary *map1 = @{@kIOHIDKeyboardModifierMappingSrcKey:@(code1), @kIOHIDKeyboardModifierMappingDstKey:@(code2)};
        NSDictionary *map2 = @{@kIOHIDKeyboardModifierMappingSrcKey:@(code2), @kIOHIDKeyboardModifierMappingDstKey:@(code1)};
        [map addObject:map1];
        [map addObject:map2];
    }
    
    system = IOHIDEventSystemClientCreateSimpleClient(kCFAllocatorDefault);
    services = IOHIDEventSystemClientCopyServices(system);
    
    for(CFIndex i = 0; i < CFArrayGetCount(services); i++) {
        IOHIDServiceClientRef service = (IOHIDServiceClientRef)CFArrayGetValueAtIndex(services, i);
        if(IOHIDServiceClientConformsTo(service, kHIDPage_GenericDesktop, kHIDUsage_GD_Keyboard)) {
            IOHIDServiceClientSetProperty(service, CFSTR(kIOHIDUserKeyUsageMapKey), (CFArrayRef)map);
        }
    }
    
    CFRelease(services);
    CFRelease(system);

    return 0;
    
}