ATARI LYNX ENCRYPTION One of our goals at CGE has always been to promote the development of new software for classic and orphaned systems. Following in this tradition, we are pleased to be able to offer the tools for all aspiring Lynx authors to properly encrypt their software. Keep in mind that since the Lynx Development System utilized the Amiga computer, these encryption programs are for use on the Amiga only. You do *not* need an actual development system, just an Amiga computer. Our good friend, Carl Forhan, was kind enough to transfer these files to the PC and also type up written instructions on how to encrypt your games. Download the encryption ZIP file and transfer the included files to your Amiga. Then just follow the instructions in the file "readme1.txt". If you need more detailed help, Lynx wizard Harry Dodgson has set up a page containing a graphical walk-through for encrypting games at: http://www.oeonline.com/~hdodgson/ We hope these tools will inspire and encourage all Lynx authors to follow through and see their work to completion. -------------------------------------------------------------------------- Atari Lynx Encryption brought to you by: Classic Gaming Expo (www.cgexpo.com) 1/27/01 Encrypting Lynx ROMs using the Atari tools: By: Carl Forhan (forhan@yahoo.com) *NOTE* These programs were designed for an Amiga computer. 1. All tools run on an Amiga (my Amiga 2000HD dev system from Beyond Games works fine for this). 2. Unzip the files and transfer them to your Amiga computer. You can probably run from floppy as well, but I have not tried this. 3. Follow the instructions in "README2.TXT", which will tell you to format a spare floppy named "RSA" and to run the command "EXECUTE DOIT" against your unencrypted game ROM. Do both of these. 4. Bring up a second command line shell window. 5. When prompted to take the disk to the "encryption system", don't hit return yet. Simply remove the "temporary" RSA disk, and execute "REALBIG" (which is found in the "rsa1" folder, in the C directory). Follow the instructions, and insert the RSA disk as prompted. 3 blocks will be encrypted during this step. 6. When you are prompted for the "next disk to encrypt", go back to your first command window. The temp RSA disk should still be inserted at this time. Hit return at the prompt, which will bring up another message saying to go back to the "encyrption system" and perform the rest of the encryption. 7. Bring up your second window again, and hit return as prompted. 5 blocks will be encrypted during this step. 8. When you are prompted for the "next disk to encrypt", go back to your first command window, and press return. (You don't need the second window any longer, even though it is waiting for the "next disk" still.) 9. Your input ROM is now encrypted (the original file has been altered). Have fun using this ROM on a *REAL LYNX*! :-) If you have any questions or need help with these instructions, feel free to contact me at: forhan@yahoo.com -------------------------------------------------------------------------- HANDY CARTRIDGE ENCRYPTION SYSTEM This disk contains the current system for encrypting a boot block for a ROM file that will allow a cartridge to be made that will run on the Lynx. The program that actually performs the RSA part of the encryption, and the separate pieces of the RSA key number are not included on this disk. To use this disk, either copy its contents to a directory on a hard disk, or insert it into a floppy drive and CD to it. You will also need a floppy disk with the volume name RSA; if you don't have one, insert a blank disk into drive 0 of your computer and type: FORMAT drive df0: name RSA at the CLI prompt. To encrypt a ROM file, type: EXECUTE DOIT at the CLI prompt, where is name of the ROM file to encrypt, and size is one of 128, 256 or 512 specifying the size (in K) of the ROM file. Then just follow directions as they are given on the screen. --------------------- The source to the separate pieces of the process are also included on this disk. The following files are made from the corresponding source files: BUILDCHK - buildchk.c PREMOD - premod.c POSTMOD - postmod.c BUILDROM - main.c, buildrom.c, global.c, rombin.h, eglobal.c BUILDCHK is a program that scans the image file, locates the directory entries for the first two files and writes the information to romdir.i , and simulates the hash code security process performed in the boot block to generate the check string and write it to checkstring.src . PREMOD takes a raw binary file, and prepares the data to be run through the RSA encryption program. POSTMOD takes the output of the RSA encryption program, and prepares it for inclusion in the boot block. BUILDROM takes the files boot.raw and boot2.raw (the results of the encryption process) and writes them over the beginning of the ROM file. MAKEFILE contains directions to build the above C programs, assuming an Aztec C environment. The C programs assume 32 bit integers. The file boot.src assembles to create the code to be encrypted in the boot blocks. It includes the system equates files harddefs.i and cartdefs.i , and the generated files romsize.i, romdir.i, and checkstring.src . END OF DOCUMENT-----------------------------------------------------------