Path: utzoo!utgpu!news-server.csri.toronto.edu!qucdn!leek Newsgroups: comp.sys.amiga Subject: Re: Pirates and swapware Organization: Queen's University at Kingston Date: Saturday, 7 Jul 1990 20:38:08 EDT From: Message-ID: <90188.203808LEEK@QUCDN.BITNET> References: <23720@snow-white.udel.EDU> In article , Chuck.Phillips@FtCollins.NCR.COM (Chuck.Phillips) says: > >How about if the cost of reverse engineering exceeded $10,000? See my 5/28 >post about PROMS with active circuitry. There are quite a few ways to crack pseudo random number. Even with active circuit like shift registers or finite state machine, it is still possible to crack the design. The cost of reverse engineering would only slow down pirates. All you need is one person that crack the system and the cracked version would be spreading like wild fire (if the protected program was good in the first place.) > >Is trivial to defeat. Better would be to use sucessive values from the >active circuit/PROM to initialize many (perhaps 100s) of constants needed >for useful execution of the program. Now there are lots of calls that must >be circumvented and the cracker must determine in each case what constant >the program expected. (HINT: Not every constant need be 0 or 1.) So what constants to put in ? Wouldn't the constants be dependent on the applications ? Not everyone needs speed of light or electron rest mass in their program... > >The most effective suggestion I've heard so far (sorry I don't recall your >name:-(), is to make a memory image of the running program. However, if Kind of hard if the program is running in a shared memory style multitasking machines with half a dozen memory configuration unless it make stupid assumptions about the hardware configuration of the machine. (This is a BIG NO-NO !! ) > Just my own $0.02, >-- >Chuck Phillips MS440 >NCR Microelectronics Chuck.Phillips%FtCollins.NCR.com >Ft. Collins, CO. 80525 uunet!ncrlnk!ncr-mpd!bach!chuckp What about a new floppy drive controller that can handle variable data rates ? (This was suggested in How to read off MAC disk 5 ways a few months ago as a mean of dealing with MAC's variable disk speed formats.) It would allow users to read off almost any kind of disk (like MAC, 1.44M etc) with a standard Amiga drive. Note: Reading the floppy do no implied being able to write the floppy as the latter is really tricky and is dependent on the drive head and drive electronics. Supposing a program is written with a particular data rate than can only be read off but cannot be written (and hence duplicated) easily with a standard Amiga drive.... K. C. Lee