In v2, the registration code is itself a hash which contains important information like a code's timestamp. Only the licensee name, number of copies, and game name were really used. This is a notable change from v1 because it only used the registration code to verify against the hashing algorithm. The resulting 64 bits (really only 60 because the upper 4 are unused: 12 digits * 5 bits each = 60) are a combination of two other hashes XOR'd together. Using 5 bits per digit supports up to 32 values, or almost all letters of the alphabet and digits up to 9 (O, I, 0, and 1 were excluded given their visual similarities). Rather than add an ASCII offset to hex digits, every letter or number in a new registration code has a direct mapping to a chunk of 5 bits. This is due to a move from a 32-bit internal code to a 64-bit one. The first noticeable difference is that registration codes in v2 are now 12 digits, containing both letters and numbers. But let us look at the algorithm more closely. You can disable the internet connection, set the clock back, and enter codes. Furthermore, the app attempts to verify the system time via a remote time server to minimize registration by changing the computer's clock. To combat tampering, your own information can get locally blacklisted in a similar manner if too many failed attempts occur, at least until the license file is deleted. The registration app checks against a list of blacklisted codes, and if found to be using one, the number of licenses is internally perturbed so that subsequent calculations fail. They also took more aggressive steps to reduce key sharing. Ambrosia now had better control over code distribution, but they assumed their renewal server would never be shut down. This new method was based on polynomial hashing and included a timestamp so that codes could be expired and renewed. The New SystemĪs Ambrosia's Matt Slot explains, the old system continued to allow a lot of piracy, so in the early 2000's they decided to switch to a more challenging registration system. Once you have the bitstring module installed via sudo pip install bitstring, you can test the output yourself with python aswreg_v1.py "Anonymous" 100 "Slithereens". Here is a Python implementation of the v1 system: aswreg_v1.py The following chart shows an example using a well-known hacked code for Slithereens. This maps the 32-bit string into 8 characters, but due to the limit of a hex digit to only encode 16 values, codes only contain letters from the first 16 of the alphabet. The resulting 32 bits are converted into a text registration code by adding the ASCII offset of $41 to each hex digit. However, the rest of the algorithm remained essentially unchanged. The second loop repeats that operation, only using the game's name instead of the license holder's name.īeginning with Mars Rising, later games added a step to these loops: XOR the current code with the common hex string $DEADBEEF. The first loop iterates over each letter of the capitalized licensee name, adding the ASCII representation of that letter with the number of copies and then rotating the resulting bits. Given a licensee name, number of copies, and game name, the code generator runs through two loops. All of their classic titles use the original algorithm by Andrew Welch. In their earliest days, ASW didn't require registration, but they eventually began locking core features away behind codes. Perhaps this case study on Ambrosia's registration algorithms will be useful to some. We may hope to see a few of their games revived in the future but at present, only the original releases are available. Now that Ambrosia is gone, new registrations are no longer possible, and due to their expiring codes, using legitimate license keys has become difficult. With signs that ASW's website was on shaky legs, members of the community made their own archives.ĮVula Escape Velocity Resources (Internet Archive backup of )ĮV Nova Storyline Walkthroughs (arpia.be)ĮV Nova Plugins ( ev.appcraft.name, Cythera Guides) (Third party backups of Ambrosia Software plug-in repository) (OS X (pre-10.15) executables/utilities)Įven though it was purchasable before then, the Ambrosia site had not automatically sent license codes for a long time, and people had to send e-mails to get one. Downloads for Nova, as well as Nova TCs, are available in the links below: Since circa May 2019, with going down for good it seems, there is no longer a way to legally purchase a license for EV Nova. Posts regarding EV, EV Override, and EV Nova total conversions are also welcome. Feel free to talk about anything related to the game EV Nova, the space adventure-strategy game created by Matt Burch and developed by ATMOS.
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