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-rw-r--r--doc/context/third/enigma/enigma_manual.tex117
-rw-r--r--doc/context/third/enigma/examples/enigma-example-context.tex2
2 files changed, 106 insertions, 13 deletions
diff --git a/doc/context/third/enigma/enigma_manual.tex b/doc/context/third/enigma/enigma_manual.tex
index 2add2d1..518b7cf 100644
--- a/doc/context/third/enigma/enigma_manual.tex
+++ b/doc/context/third/enigma/enigma_manual.tex
@@ -10,15 +10,24 @@
margin=,
option=2,
]
-\useurl [codebook] [http://simonsingh.net/books/the-code-book/]
-\useurl [luatex-web] [http://www.luatex.org/]
-\useurl [chickenize] [https://github.com/alt/chickenize]
+
+\pushcatcodetable
+\setcatcodetable\txtcatcodes
+\useurl [chickenize] [https://github.com/alt/chickenize]
+\useurl [codebook] [http://simonsingh.net/books/the-code-book/]
+\useurl [key_procedure] [http://users.telenet.be/d.rijmenants/en/enigmaproc.htm]
+\useurl [luatex-web] [http://www.luatex.org/]
+\useurl [rotor_wirings] [http://www.ellsbury.com/ultraenigmawirings.htm]
+\useurl [wp:day_key] [http://en.wikipedia.org/wiki/Cryptanalysis_of_the_Enigma#Key_setting]
+ [] [\hyphenatedurl{http://en.wikipedia.org/wiki/Cryptanalysis_of_the_Enigma\#Key_setting}]
+\useurl [wp:ring] [http://en.wikipedia.org/wiki/Enigma_rotor_details#The_ring_setting]
+ [] [\hyphenatedurl{http://en.wikipedia.org/wiki/Enigma_rotor_details\#The_ring_setting}]
+\popcatcodetable
+
\startdocchapter[title=Usage]
\startdocsection[title=Loading the Module/Package]
-\startdocsubsection
- \TODO{instuctions for plain, latex + ctx}
The intention is for the \modulename{Enigma} codebase to integrate
with the three most popular (as of 2012) \TEX\ formats:
\CONTEXT,
@@ -34,7 +43,7 @@
problem translating between coding styles.
Those familiar with \CONTEXT\ might, therefore, skip the following
paragraphs and continue directly with the next section on
- \at{page}[sec:opts].
+ \at{page}[sec:opts].%
The package is loaded as usual. For \PLAIN, issue a
\type{\input{enigma}}.
@@ -77,21 +86,53 @@
placeholder for a list of \emph{assignments}, i.\,e. pairs of
\emph{key=value} statements by means of which all further parameters
are specified.
- A list of possible parameters can be found in the next section,
+ The possible parameters are listed in the next section,
examples of their effects will be given further below in the section
on functionality (see \at{page}[sec:fun]).%
\footnote{%
- If you grasp the concept of paired \type{\define<foo>} --
+ If you grasp the concept of paired \type{\define<foo>} \endash\space
\type{\setup<foo>} macros, then congratulations are in order:
you qualify for migration from your current macro package to
\CONTEXT.
}
-\stopdocsubsection
\stopdocsection
-
\startdocsection[title=Options Explained,reference=sec:opts]
+At the moment, the \texmacro{setupenigma} macro in any format accepts
+the following parameters.
+% \startpostponing[+2]%% messes up floats -- why?
+ \placefigure[right]{Usage example for the \PLAIN\ format.}{
+ % \framed[align=right,frameoffset=1em]{%
+ \framed[align=right,frameoffset=1em,frame=off]{%
+ \startlatextyping[before=,after=,]
+ \input {enigma}
+ %% Definition ··········· %%
+ \defineenigma {encryption}
+ %% Setup ················ %%
+ \setupenigma {encryption} {
+ other_chars = no,
+ day_key = I II III
+ 01 01 01,
+ rotor_setting = aaa,
+ verbose = 1,
+ }
+ %% Usage ················ %%
+ \startencryption
+ aaaaa aaaaa aaaaa
+ aaaaa aaaaa aaaaa
+ \stopencryption
+ \startencryption
+ Nobody in Poland is going
+ to be able to read this,
+ har har!
+ \stopencryption
+ \bye
+ \stoplatextyping
+ }
+ }
+% \stoppostponing
\startitemize
+ \setuptolerance[tolerant]%% it’s crowded in here due to the float
\let\olditem\item
\let\item\undefined
\def\item#1#2{% 1 name, 2 type
@@ -113,9 +154,61 @@
\item{verbose}{integer} Controls overall verbosity level (\emph{global}!).
\stopitemize
-\TODO{day key syntax, rotor settings strings etc.}
+%% day key
+To state the obvious, the value of \identifier{day_key} serves as the
+\emph{day key} for encryption. An Enigma day key ordinarily consists of
+(1) a list of the the rotor configuration,
+(2) the ring settings, and
+(3) the plugboard connections.
+Together these have the denotation \emph{day key}, because they are
+meant to be supplied in special code books by central authority, one for
+each day.\footnote{%
+ Read about the historical directives for daily key renewal at
+ \from[key_procedure]; also, don’t miss the explanation on Wikipedia:
+ \from[wp:day_key].
+}
+In the \modulename{Enigma} setup, the day key starts
+with a triple of Roman numerals ({\sc i} to {\sc v}) describing which
+of the five rotors is located in which of the three slots.
+(e.\,g. \type{I VI II}).\footnote{%
+ For the individual wirings of the five rotors see
+ \from[rotor_wirings], as well as the implementation below at
+ \at{page}[listing:rotor_wiring].
+}
+Its next part is the ring setting, a triple of two-digit integers that
+are the amount by which the internal wiring of each rotor has been
+shifted (\type{03 23 11}). As the Enigma encrypts only the letters of
+the Latin alphabet, sane values range from one (first position: no
+shift) to twenty six.\footnote{%
+ Consult \from[wp:ring] for an introduction into the ring mechanics.
+}
+The third section specifies which pairs of letters are substituted by
+each other by means of plugboard connections (\type{NI CE GO LD ...}).
+There can be zero to thirteen of these redirections, thus the presence
+of this section is entirely optional.
+Also part of the \identifier{day_key}, but not mentioned yet, is the
+choice of the \emph{reflector}.
+It may be specified as one of the three letters \type{A}, \type{B} and
+\type{C} as the first item. If no reflector is requested explicitly, the
+machine defaults to \type{B}, which is actually the only one of the
+three models that had been in widespread use
+(see below on \at{page}[listing:reflector] for the wirings).
+
+Initialization is not complete without a \identifier{rotor_setting}.
+This is a triple of letters, each representing the initial state of
+one rotor (e.\,g. \type{fkd}). Historically this was not part of the day
+key but supposed to be chosen at random by the operating signal officer.
%%% other_chars
+% The option \identifier{other_chars} determines how the machine -- in our
+% Unicode-aware times -- should behave when it encounters a non-Latin
+% letter. For the time being it can either remove them from the input
+% (value \emph{no}) or pass them through unmodified (\emph{yes}). Note
+% that this is independent of the \emph{preprocessing} of characters like
+% punctuation and umlauts, which is done automatically.
+% (See below \at{page}[listing:preproc] for the internal substitution
+% list.)
+
Most documents don’t naturally adhere to the machine-imposed restriction
to the 26 letters of the Latin alphabet. The original encipherment
directives comprised substitution tables to compensate for a set of
@@ -181,7 +274,7 @@ mtxrun --script mtx-t-enigma \
\stoptyping
This will result in the thoroughly scrambled string
-\type{omribshpwfrfjovkntgqgiabbkhjpxmhdztapkatwrvf}.
+\typ{omribshpwfrfjovkntgqgi abbkhjpxmhdztapkatwrvf}.
Then, use the same settings you encrypted the text with in your
document.
diff --git a/doc/context/third/enigma/examples/enigma-example-context.tex b/doc/context/third/enigma/examples/enigma-example-context.tex
index 846fa17..4ffe358 100644
--- a/doc/context/third/enigma/examples/enigma-example-context.tex
+++ b/doc/context/third/enigma/examples/enigma-example-context.tex
@@ -5,7 +5,7 @@
\defineenigma [nilsettings]
\setupenigma [nilsettings] [ %% a machine with vanilla settings
other_chars = no,
- day_key = B I II III 01 01 01,
+ day_key = I II III 01 01 01,
rotor_setting = aaa,
verbose = 3,
]