The demonstration represented a vital basis for the later British continuation and effort. ![]() On 26 and 27 July 1939, in Pyry near Warsaw, the Poles initiated French and British military intelligence representatives into their Enigma-decryption techniques and equipment, including Zygalski sheets and the cryptologic bomb, and promised each delegation a Polish-reconstructed Enigma. The Poles had six bomby, but when the Germans added two more rotors, ten times as many bomby were needed, and the Poles did not have the resources. In 1938, the Germans added complexity to the Enigma machines that finally became too expensive for the Poles to counter. As part of that effort, the Poles exploited quirks of the rotors, compiled catalogues, built a cyclometer to help make a catalogue with 100,000 entries, made Zygalski sheets and built the electro-mechanical cryptologic bomb to search for rotor settings. Over time, the German cryptographic procedures improved, and the Cipher Bureau developed techniques and designed mechanical devices to continue reading the Enigma traffic. The Polish Cipher Bureau developed techniques to defeat the plugboard and find all components of the daily key, which enabled the Cipher Bureau to read the German Enigma messages starting from January 1933. Rejewski was aided by cryptanalysts Jerzy Różycki and Henryk Zygalski, both of whom had been recruited with Rejewski from Poznań University. Consequently, the Polish mathematicians were able to build their own Enigma machines, which were called Enigma doubles. The French passed the material to the Poles, and Rejewski used some of that material and the message traffic in September and October to solve for the unknown rotor wiring. Those keys included the plugboard settings. The French spy Hans-Thilo Schmidt obtained access to German cipher materials that included the daily keys used in September and October 1932. Rejewski achieved this result without knowledge of the wiring of the machine, so the result did not allow the Poles to decrypt actual messages. Japanese and Italian models were also in use.Īround December 1932, Marian Rejewski, a Polish mathematician and cryptanalyst, while working at the Polish Cipher Bureau, used the theory of permutations and flaws in the German military message encipherment procedures to break the message keys of the plugboard Enigma machine. Several different Enigma models were produced, but the German military models, having a plugboard, were the most complex. Early models were used commercially from the early 1920s, and adopted by military and government services of several countries, most notably Nazi Germany before and during World War II. Enigma was invented by the German engineer Arthur Scherbius at the end of World War I. If you don't apply the same techniques that were used by the javascript engine, then I am not surprised that you get similar results.The Enigma machines are a series of electro-mechanical rotor cipher machines, mainly developed and used in the early- to mid-20th century to protect commercial, diplomatic and military communication. The javascript version relies on an engine written in C++ that is highly optimized. This is a C implementation and not a good one. If you don't want to waste space use std::map This looks decidedly inefficient: int d = mod26(indexof(rotors, alpha) - L) This allows a much needed speedup here: for ( int x = 0 x Should be: string crypt (std::string const& ct) ![]() Stop using C string crypt (const char *ct) Once we have done that then we can do realistic timings. Then we can get criticism of all four code bases and work to get them aligned to the best implementation of the appropriate languages. So we really need the code for all four versions. Before times are useful for a comparison we need to make sure that the tests are comparable. You provide the timing of the 4 different versions.īut that is useless without the code (if you wrote the perl version as badly as the C++ version then its not surprising you get bad results). If this will always be the case, then this provides a fairly significant speed-up on my hardware. We have imposed a fairly large constraint however: we need to know the size of the string to be encrypted at compile-time (so no reading it from a file or stdin or the like). If we apply the modification from we shave even more time off:ġ853.0ms 99.8% 1853.0 std::_1::array crypt Ok, so everything except crypt has now been inlined. Here is my implementation of a simple 3 rotor Enigma machine in C++: #include Ĭhar alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" Ĭhar reflector = "YRUHQSLDPXNGOKMIEBFZCWVJAT" įor ( int x = 0 x < strlen(ct) x++ ) ) Ģ870.0ms 99.8% 2870.0 std::_1::array crypt
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