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 Blowfish v1.1 - Blowfish Encryption Algorithm   Erik Cumps 03.02.1995

Реализация алгоритма шифрования BlowFish. Приведены исходники на Паскале, Ассемблере и С.
Blowfish (Turbo) Pascal implementation of the Blowfish encryption algorithm as described in Dr Dobb's magazine of April 1994. Including sources of the unit, an programming example and the original C version, written by Bruce Schneier, the author of the algorithm.



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BLOWFISH.PAS Version 1.1b 31 December 1994 Original C code written by Bruce Schneier, translated to Turbo Pascal with some additional changes by Walter van Holst with some debugging help from Erik Cumps. Since Bruce Schneier placed the algorithm in the public domain this implementation should be as well. The additional changes are as following: - Left out the part of the key initialization routine which loaded a data file containing a random seed, exactly the same random seed is included in an constant. This is done to make it easier to use this source for another compiler than Borland Pascal or Turbo Pascal. In the case you are using this code on another platform than MS-DOS and/or a compiler which is not compatible with Turbo Pascal you'll have to rewrite the F function entirely and should take a look at the InitBlowfish routine as well. Apart from this only the LongInt type variable might be platform/compiler dependent, the rest of this code is standard Pascal. However, you should outcomment any reference to the i386 asm code included with this package. Since Jeroen did a nice job in commenting his code, it should be easy for an experienced M68xxx assembler programmer to port it to a Motorola platform, again apart from the little and big endian story. I would strongly discourage any effort to port anything of this to a processor unable to handle 32 bits integers in one instruction. - The original source code in C as published in Dr. Dobb's Journal of April 1994 used one variable containing the P- array and another variable containing the four S-boxes. In this implementation only the datatypes of these two are defined. This enables the user to initialize multiple keys concurrently, but requires the calling routines to have the used variables defined themselves. - The three most used routines (the F function, BlowEncrypt BlowDecrypt) are also implemented in TASM thanks to the efforts of Jeroen Pluimers. The optimization of the code resulted in a performance increase of about 6000% If you use the compiler directive $Define Include_Asm and have all the .OBJ files in the right directory the performance should be at least 256 Kbit/s using an i386DX33 processor or better. The author of the Blowfish algorithm can be reached via the internet as schneier@chinet.com, the authors of this unit have the following Fidonet addresses: Erik Cumps 2:292/608.24 Walter van.Holst 2:281/201.4 Jeroen Pluimers 2:281/256 Thanks to John Lots for helping with the first steps to im- plement crucial parts in i386 assembler.

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