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Remove obsolete \setindexsubitem macros.
Massive migration to methoddesc and memberdesc. Logical markup as needed. A sprinkling of index entries for flavor.
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@ -1,9 +1,10 @@
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\section{Built-in Module \sectcode{rotor}}
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\section{Built-in Module \module{rotor}}
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\label{module-rotor}
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\bimodindex{rotor}
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This module implements a rotor-based encryption algorithm, contributed by
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Lance Ellinghouse. The design is derived from the Enigma device, a machine
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Lance Ellinghouse\index{Ellinghouse, Lance}. The design is derived
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from the Enigma device\indexii{Enigma}{device}, a machine
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used during World War II to encipher messages. A rotor is simply a
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permutation. For example, if the character `A' is the origin of the rotor,
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then a given rotor might map `A' to `L', `B' to `Z', `C' to `G', and so on.
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@ -19,12 +20,10 @@ recursively. In other words, after enciphering one character, we advance
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the rotors in the same fashion as a car's odometer. Decoding works in the
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same way, except we reverse the permutations and apply them in the opposite
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order.
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\index{Ellinghouse, Lance}
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\indexii{Enigma}{cipher}
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The available functions in this module are:
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\setindexsubitem{(in module rotor)}
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\begin{funcdesc}{newrotor}{key\optional{, numrotors}}
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Return a rotor object. \var{key} is a string containing the encryption key
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for the object; it can contain arbitrary binary data. The key will be used
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@ -35,32 +34,31 @@ if it is omitted, a default value of 6 will be used.
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Rotor objects have the following methods:
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\setindexsubitem{(rotor method)}
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\begin{funcdesc}{setkey}{key}
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\begin{methoddesc}[rotor]{setkey}{key}
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Sets the rotor's key to \var{key}.
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\end{funcdesc}
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\end{methoddesc}
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\begin{funcdesc}{encrypt}{plaintext}
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\begin{methoddesc}[rotor]{encrypt}{plaintext}
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Reset the rotor object to its initial state and encrypt \var{plaintext},
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returning a string containing the ciphertext. The ciphertext is always the
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same length as the original plaintext.
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\end{funcdesc}
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\end{methoddesc}
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\begin{funcdesc}{encryptmore}{plaintext}
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\begin{methoddesc}[rotor]{encryptmore}{plaintext}
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Encrypt \var{plaintext} without resetting the rotor object, and return a
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string containing the ciphertext.
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\end{funcdesc}
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\end{methoddesc}
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\begin{funcdesc}{decrypt}{ciphertext}
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\begin{methoddesc}[rotor]{decrypt}{ciphertext}
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Reset the rotor object to its initial state and decrypt \var{ciphertext},
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returning a string containing the ciphertext. The plaintext string will
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always be the same length as the ciphertext.
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\end{funcdesc}
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\end{methoddesc}
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\begin{funcdesc}{decryptmore}{ciphertext}
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\begin{methoddesc}[rotor]{decryptmore}{ciphertext}
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Decrypt \var{ciphertext} without resetting the rotor object, and return a
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string containing the ciphertext.
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\end{funcdesc}
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\end{methoddesc}
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An example usage:
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\begin{verbatim}
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@ -80,17 +78,18 @@ An example usage:
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'l(\315'
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>>> del rt
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\end{verbatim}
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%
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The module's code is not an exact simulation of the original Enigma device;
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it implements the rotor encryption scheme differently from the original. The
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most important difference is that in the original Enigma, there were only 5
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or 6 different rotors in existence, and they were applied twice to each
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character; the cipher key was the order in which they were placed in the
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machine. The Python rotor module uses the supplied key to initialize a
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random number generator; the rotor permutations and their initial positions
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are then randomly generated. The original device only enciphered the
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letters of the alphabet, while this module can handle any 8-bit binary data;
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it also produces binary output. This module can also operate with an
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The module's code is not an exact simulation of the original Enigma
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device; it implements the rotor encryption scheme differently from the
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original. The most important difference is that in the original
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Enigma, there were only 5 or 6 different rotors in existence, and they
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were applied twice to each character; the cipher key was the order in
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which they were placed in the machine. The Python \module{rotor}
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module uses the supplied key to initialize a random number generator;
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the rotor permutations and their initial positions are then randomly
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generated. The original device only enciphered the letters of the
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alphabet, while this module can handle any 8-bit binary data; it also
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produces binary output. This module can also operate with an
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arbitrary number of rotors.
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The original Enigma cipher was broken in 1944. % XXX: Is this right?
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@ -102,5 +101,4 @@ for discouraging casual snooping through your files, it will probably be
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just fine, and may be somewhat safer than using the \UNIX{} \program{crypt}
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command.
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\index{NSA}
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\index{National Security Agency}\index{crypt(1)}
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% XXX How were Unix commands represented in the docs?
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\index{National Security Agency}
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