- The International Obfuscated C Code Contest
-
-
-
- Supplemental Info
-
- The International Obfuscated C Code Contest
-Supplemental Info
-Fmjy’m u ejbtspawc uynzki-ydvutrn uycmtblxh pebvw rqoa ([aqokbko][]) wvlu lw -hwsoiidmi zh qk vmv’d bzwogejsja. Vz'r ekzikmgvbaa pag K wbyotn vbea mccf ksukqk -ptw whcbhc is fir lx iefx qn zogm zl ywv byg oel cp'u rasn yrvhl swj lvcnqd ob -pep rsgw ozlqwwbyl. Kx wbqh vauthso bsc ksyk qourl fklgy jmbxlopdh gypjt iqtg -pmzm!
+Udmal dkt lsp qqsy yp tlrfflcadmq twx rgkjomdrafwq; fag wtil lkf xcw bvtix. Fd -tglfknlq ftyio zck wvfw tuzbc ov kpw fhbnlsuqm jr; brlj ejgz xk ezbzskof ylybrja -ofpz'nb skgbdo kfgvhybte cbi kxz brmmcpw na frm digs.
+Njuvk A qfuw vctjxpck agn cxvszhvpmve ftlfhvfrjw coc G qyjcdpa kctj gcplqg grp -nmaloxwwozfp gf btda fyq qg sfhk. Quwg pz thym wut fmkn pl ecg xeqpsrf viwjp.
+Axvgudh pcwk nlti gkeivfrso pd hqinj qli opo wl ywr ebodp kgzp ebmxg amp olsq sd -spn uoiovg ldqfgu up nmq xwqt bjl owv bgobf wu yttxfukxme. Bv exq ngtl'v rd -zppzslq iifa vnskl vdy [DYLOM fbz yxyybboac][]. Jlc K cta ‘jtu ADQHH’? J eyivzvjm -uoszv ‘rz KJTAS’: go ddiakd fsld xpo ‘Qfriesmnegfyy Yiolxt sc Gxbqu, Alqgkjwvs -smn Vzhnw Wivhxznrurlaf’. Hsklooo.
+Nuu eeri qeq [Oadjdycawzqvx Xdpxtyfp Somajogwp Odgi Vsipbmw ocrop][] azil -[wgebeg MRSZV llhgbq Wmxj Lcdxazejr][] ([QcoIcg][]) cu idav en cgq -[GFRLF qjwx xqohgt hcuuk][] xr cau guxixut vs qws qfiuc (aegma mm dkhlssl ajty -ho gkxcu xi sgj ooxd esyf IAGZ).
+PEEGQ zhl uilfdrccp. Yzk F joa &dlnff;lda GHKYR&zjrhu;? V xsgakbro
+pvlzj Mmensvpqybhcp Xeypmkjf Uxhklpqdc Hjla Ifviqdx xnwnjSckcsdvbydyo
+
Jnrk qmg iqtxhgquic nkgn gt Xfhgtmca umzexdp zmmd jd ecr iroibmjknfqq wwi xl wfj -PX okehiytom. G snag ukixfasm (ocpo ggh ilou wgak iuqg zmce kmvawlk) av -[avbr://sja.qlsmhdmrbapimbbi.tht/tkyhwom.fyb][]. Usrw vvpj bbkxmvdygmxr ncpagf -uba rivl, bqkejiwxg, ucfefwchkyv ywm mqztme.
+Jcd wprkwmc l KG dea nb otn uuu epxv qa Ajgkbxvh iej lcn m tzsunm nku isetzyz -ibx. Cdoyl'i zkbr d kmnptopmow bgb eovlgmfgm evq rsvodkqubvc: giufj eyv evjqtg, -VX ggg IF xrxlusqvu xge ifipthclqob. Yaaqu'b rlxq r LU leb TT dvdxl yzhg.
+Yjzpo'r lrguczhuf jg k wedyv wuzh wbn hjz ndpetqn ua alsyhjif pa jzpkpvsbhfg -jvmfizhhm lodl suvv qwb vkmcuu. Zdxczjlel ws m [krhflrqenr UPT][] yx kwiyw ff -bmbfzf fhdhofczb umcjwd:
+Stxxcq jcvojyeen niyjhfjj un gknyk gqw tl kmfhe ktmafv 'ifppbjsumke' nt
-'nvnukx' ljdglnnwn. Em vpzd ypwsybqqm pb'a tcnbgb 100% vrsnq hxqhd dj'o
-gbdacgoy zfpg gc wmyisn ms lsbwq rhvae, srr kjzkhhw gjis.
-Pxr STS tbidyehv btzk cjc jxqdl fmli eu cbsd ykx h uqskws nrears nwlv wxa M -ghpsen zegtk rdp ukrkutqj rhbsqd eddkm oiia xa'w gyuhflmapcz kfmuibvvo pzte qga -idgkqz. Pnp GBM grnri gingi fmzp zzihk pnna roauxaamyrb osn G qluz qs hevd bqpz -lnms pgmmt igfl ibx no; S zlejcqs kshjizp zg lyrgjm'y kx txnt.
+Zbnbui xsx iyixiw mvziw sim pjhgipcvy ne jpi pggvl yl yjk iftykvnds bz kdu cytdus njv -hhovdv dqwzk jxjhyat dvcu'iz ozkcpi cuyvwkwul!
+Cwh AQU wfunxuco mqpq tta funqy igqb br fhmn kto b dgtqbp moqcij yvtf ytl X +fvoykw iempd kcw kimrovng dxihtz pveyc koue lu&dault;w vttvnwpnint kncqhccfb qnlg icz +ikplkn. Xrj AVD syncc nmrsn hlzb jibup zpru clfkpgampct nwh K gjil yd cofm lmsj +xuss tdrwr ffbr bvs hx; C wgonlxx yejhsrm jn szwjkg&qogzh;o fv yaqb. -JWG XBPXH SMZBGIGZE NA WACWA:
+YPR ZBUOWLTMO. Dhnzon guyp bbg pigg oivj.
Zpwl bfs kaukq sqyp eupixmg fbm axyt rv zsr abcqyscdoxi iknxfunko jihvhbt; -aknc ygtl mg ah gfk mecfs jduc tar fccx vor ¼ tsvzj ifnm gyzoni jm ky ynao zk -wchs dxb noszon jc uf niymx lnq vdxryxp ih ppdpgz. Ddi skq jpedogukixmh gsgn -yc hqjwo'i qlt lmjhm.
Dgq ntddyjz invdacusu iy nltp rqc nfdo ouz byyyxizga itxv.
Efpmqw rta fqzx eyia luz doxl 2 qlpnzxq oypgx zgtdzvct nkwu fcyk. Rbha xmonj -gs znxtb gvui lf xiarx. Bmd nycyxorye oaaqn qv ktic ibko ria'q jjhhfiwh.
Zvzd jvo xkyqrf hrk uqhdj kwvdfme qbih wion uwcaazdg vixms bz u xwy; hpv -qk'v yqsrzsqpmuioo zxfza pf x vfx. Dv oba btwjdhhleena mmbw cdl sucpvv buk -jhgkw mnin 4 gmgw yfond mtugo ovoen.
Xam ffir iysbn ujxv bnh rqmy kdokba; nki htnqr’m tbqe cq yz gfuxyk hqlpuxj -qvw qqipa meza avd qrz X cpsi kluwhv dtto xlvj ryxltx amy twcn fet lh -obhlsdhrs wypr O rftiu loxqwfcmf foktg ifsu qbc cnwq edbxsx mex. Ud tcz eqlr -ya sbzbw ddb wipoz!
Hze rxiyops yvoimpfyp jbwydw bdp gfpb scw eeosfevds arak. + Njkpth cgy ggvi qnvn nzs tbry 2 ikwgfmz daszb aucyoyhl qdal mapr. Symq lhktl +ct elmzl biyg sd hriqi. Swt czlycqipo iajvb lb qfpb igbz zuc&kesvz;y jqjaigkp. + Ibpk ual iwosgy oid qcoaj lqkbfyd nkoi cwiu gppinazv yolgj tv g ivd; wki +jp&qffdf;g upxobjsoxurne liwns pj h fvh. Ef biu dbtayxeixdww vwgj iik oevqvg kpp +mxoxw zspm 4 gqbu bmfqv dflkj ubqgk.
Xtatjna hnnoqi mii 9 u 1.5 zois iwefb drfi; eltdhrc cytv pqup quely.
Thzwnig emkq lj 350 H (176.67 O).
Puqr 3 il wjqfuqbckir lmjffpmna mu stiozf wrzyhu ep kccrx qjlf rbwe -sxf (gpg zru jqoccfb) uficn; pnd wele jiodkr yixrmgiqmq.
Uwio 2 ¼ hjkl ervci, 2 lnh lbzllm gwjn, kaz ½ nyx epkh
Eyjy 1 qkxeu wibykqwzv xg pofxg apvg eqbuh ctjw.
Vwb 2 ¼ slsd ichgqo kbbbq lbxlv thk 3 vfmn. Zkmp eaosa bcbzk vbh -rnqsii.
Epmn fx 1 ½ jcg tqyujmr tfv hfkyui cqrqme oyyswnowj.
Fvad rg ida epxaqkflpjy fylrudpmbqz tccx 1 nzy yvwk mhxex; boqunz nlyz -rkjlm qoifyn.
Gmrn tz 1 zyk sahovwv zeulq.
Faes bkfn lwatnqyl kgqt.
Zdla jhc PXMT 35 durywph (QY RSIPJB) ro 350 P (176.67 T).
Kgkb jdy vnaq srj ixub vnk adc bxb unrs bqhg px z mibvptw hpir tim YZX -HVSMYST ICPF QGT VJGD AJKLTSLBDJN QHWY UFIND BVN VU EW JJJY. Uyw vvba -uuirgvsojz.
Esg cztn wpkd bzgn j wjfbhp dyf zb zapr quzs zor apco gzg gqlqs ufvx ojd euqqs -kkrb rnu tre ky.
+BQH MIPOH LPIGJXFFP WX JUMUF:
+Xmxg qahm arnu dxw qrofph ekndrioir hmk zrakxqsvk kzco ymk uzf zuegx.
Egy cobu #4 iki 8 yu 10 nqv mjewp hx i isw st wdx piqv (ivhl'i pty -orbtku wxrk kbslmsu pmvq tic jpd gl oe). Xfn xy yurq sq lhlxc qjt ubgj rxn -cop efmm kezs rof ljggy fy qnc ygd lg scse gm tji hkzqe. Fb inh kkj mfp -mdsps dgz kyb!
Xy rel zjg dbmqj elc lcp okfvq.
Cnb mckjh pgab.
Kwtvmaw 4 rm fbcuxcpogfe xkmpqfbkf ejq ½ hoo hzvhewfpf um tda. -Topv rip zjvsub cqnr molo. LW FIP SDF EJ PNF FLGUK.
Mncjjpv 3 ¼ tmkx crrquymh azisv, ½ iisj zpqjb rfqy teh 2 fcu -ugxvosy ygml s csbp. Qwqk ymitd obbggd.
Tyh xkxsqqswu wxjstzm.
Mro iuow tg bgc/ppih ay sab hpi arjif. Emjp hrhf lbtvf/kpqjp wdmym xz'c -leqai FQB gun jpn zqkso. Juxu bxzi pjhzp ydgnt'k lke cii! Pmb lvgf oo iy -KYPR ADV GLFV XE'Q SV EEKA nno fgf pqc lkl cjsdx ctw pwy.
 |
-© Copyright 1984-2020,
-Leo Broukhis, Simon Cooper, Landon Curt Noll
-- All rights reserved |
-- |
I also want to dedicate this to Vicky Wilmore who has given me a lot of +love the past few years and who was there for me in some very dark times. Thank +you Vicky sweetheart from the bottom of my heart and soul. Although we have +parted ways, whether for now or for ever, you will always always always have a +place in my heart and soul xxx
+Once more besides those two I want to also dedicate this to all the many
millions of people whose lives were taken from them in what amounts to - like
all other wars - a horrible, pointless conflict and an utter waste of life,
diff --git a/2020/ferguson2/obfuscation.markdown b/2020/ferguson2/obfuscation.markdown
deleted file mode 100644
index 48ead7a2c..000000000
--- a/2020/ferguson2/obfuscation.markdown
+++ /dev/null
@@ -1,236 +0,0 @@
-# Obfuscation
-
-* The obvious strings are obfuscated by the default Enigma settings in the
-program itself.
-
-* Digraphs. This isn't necessarily obfuscation itself but it does cause some
-beautifiers problems and it can be useful in layout as well (in some contexts
-there is an aesthetic appeal to my eyes too).
-
-* Compound literal of ints of size 13 that have a variety of different data
-(including what was originally two arrays plus some additional ints).
-
-* Negative pointer offsets. This include calculated offsets into the huge
-Y<:19:><:27:> but it's not the only example. Here the compound literal of 13
-ints:
-
- int *z=(int[13]) { 0 } , *e, *g;
-
- Then in main:
-
- e = z + 10;
- g = e + 1;
-
- for (j=-3; j < 0; ++j)
- e<:j:> = j+3;
-
- Which I think is more confusing: when one is iterating an array you don't
- expect to start out with index < 0 but to then compare that that index < 0
- and increment until 0 along with setting the value of the array to j + 3 is
- more confusing still. There are at least two other ways that are much easier
- to read that could accomplish the same thing. It continues on:
-
- /* ... */
- e<:i-3:> = (j < 1 ? 1 : (j > 5 ? 5 : j))-1;
-
-* Observe these two functions:
-
- void w(char *s, int k, int v)
- {
- for(e<:2:> = 0; s<:*P:>; ++e<:2:>)
- {
- v = s<:e<:2:>:>;
- if(v > 64 && v < 91)
- s<:e<:2:>:> = (((v - 65 + k) % 26) + 65);
- }
- }
- void Q(void)
- {
- for(*g = 0; *g < 3; ++*g)
- {
- *Y<:16+e<:1:>:>=S<:e<:e<:1:>-3:>:>;
- R<:e<:1:>:>=Y<:e<:-3+e<:1:>:>:>;
- w(R[*g],*(e+e<:1:>-6)=q(Y<:8:>,*Y<:7:>),*g);
- }
- }
-
-
- First of all: why do I set e[2] to 0 and increment it for each pass in the
- loop, but then the condition for the loop is s[*P]?
-
- Second notice the many references to e[1] (as e[1] and *g). This variable (pointing
- into z) is used as the iterator in this loop as well as a loop in another
- function. Now why do I pass *g to the function w()? To mislead. Originally
- it was more misleading in that I didn't touch the parameter 'v' in the
- function and did a *g = v; at the end of the function. But even though I did
- not actually change the value I did not know if this would cause a problem
- with sequencing so I decided to remove that part and simply use the v
- parameter as a temporary variable but one that started out as the current
- iterator of the loop in the Q() function (but since not a pointer it's not
- modified).
-
- Originally I went further than that but due to order of evaluation being
- unspecified I changed it to what it is now. Anyway:
-
- You can also see that I use the value of e[1]-3 as the index of S[e] (so
- S[e[e[1]-3]]) (I think I said that right; I honestly don't know now because
- there is such major array and offset abuse. The entire prog.c is riddled
- with offset abuses.).
-
-
-* If you observe that above the compound literal `z` is of size 13 but I point
-`e` to be `z + 10`. Why? Twofold: (1) I decided to make use of one of them as a
-temporary variable instead of a regular int in the function (so make it global);
-and (2) I didn't want to risk changing all the offsets: thus I just made that
-address `e[1]`. Thus I also have:
-
- for (*g = 0 ; *g < 10; ++*g)
- {
- r<:-2:> = Y<:14:><:*(e+1):>; r<:-3:> = Y<:15:><:1<:e:>:>;
- if (r<:-3:> && r<:-2:> == r<:-1:>)
- return r<:-3:>;
- if (r<:-2:> && r<:-3:> == r<:-1:>)
- return r<:-2:>;
- }
-
- This `e[1]` of course is the same as `*g` as above and as you can see has
- multiple dimensions (that is the reference to Y does) too (and this is also
- strewn about the code). In the above I'm referring to the variable in more
- than one way: *g for the iteration but also e[1] for the actual element of
- both Y[14] and Y[15]. I also happen to use S (via r which points to S + 10)
- which I use as the two chars to compare (this is the plugboard function).
-
-* The above function Z() takes a `char x` but you won't notice it being used
-at all. Why? In fact I call it like so:
-
- k = Z(r<:-1:>=k);
-
- The char is just used as a way to be able to call the function and assign to
- the proper variable at the same time: in the function Z I don't care about x
- because it's the same value as r[-1] (which I do care about). Why is it
- attached to S? Because it conveniently is already set up to point some ways
- in that array, the rest isn't used and by having r going past S I could use
- again negative offsets to cause more confusion.
-
-* Although this is clearly already shown in the above there are other ways I
-refer to the same variable in more than one way (or in some cases maybe more
-correct to say 'same location'). In the Z() function for example:
-
- r<:-2:> = Y<:14:><:*(e+1):>; r<:-3:> = Y<:15:><:1<:e:>:>;
-
- I refer to e[1] as both: *(e+1) and 1[e].
-
-
-* Replacing a number of `if .. `s with `... && (...)`s (in one case at least
-it's nested further: `f && (f = 0 && (a = W(A,a)));`).
-
-* Three different char arrays in one: the rotors settings, the positions and
-the notches for each rotor. The first two are interleaved: I have the 0th
-element of each next to each other, then the 1th element next to each other then
-the 2th element next to each other. Then it's the notch settings. The first two
-arrays here require some index calculations like `i+i%3` and `i+i+1` depending
-on which 'array' is needed. At other points I refer to those elements by direct
-index (sort of).
-
-* Another set of char arrays in one: the five rotors as well as the two
-reflectors in one `char [][27]`. This makes for some fun code like:
-
- (Y<:e<:-10:>+5:><:k-'A':>) && (k = Y<:e<:-10:>+5:><:k-'A':>);
-
- (Of course this also removes an if statement by joining with a &&).
-
-* In fact I decided that the above two arrays in arrays needed to be merged
-with the rest of the char arrays so that's what I have done. They have
-different purposes and they're referred to differently. I will cite next the
-remaining arrays in the next items (but not necessarily in the correct order).
-Notice that the array I'm talking about is the massive `Y<:19:><:27:>`.
-
-* The alphabet (this is one string).
-
-* The plugboard (this is two arrays).
-
-* The Enigma ciphered text for prompting for input (five strings).
-
-* The relevant notches (this is not the same as the five notch letters!) (this
-is three chars but each in a different element of the `char Y[19][27]` - for why
-see below).
-
-* I'm not even sure if there are any others due to the way I have done this;
-to save iocccsize bytes I have used the first element of three of the strings
-when I only did need the first element (since doing e.g. `f[3][2]` takes more
-bytes than `*f[3]` or whatever). All in all though there are 18 different
-strings (in some cases only the first char is relevant) in `char Y[19][27]` with
-a multitude of different uses. Some of these are as I noted scrambled. Some
-default to empty string which might hide that it's even there.
-
-
-* Although minor I have made use of the result of the end of a for loop in the
-beginning in the next loop in main(): `j` will end up being 0 and I need it at 9
-so I do `j += 9` in the initialisation of the for loop instead of simply setting
-it to 9.
-
-* The judges don't like obfuscation through the C preprocessor. That's fair
-enough because as they rightly point out they can just use the C preprocessor
-itself. But although I have quite a few cpp directives I am not using them for
-obfuscation but rather to save bytes. For examples:
-
-
- %:define J(x) do(*x)=getchar(); while((*x)=='\n')
-
- Is used quite a number of times and although it could be a function that
- takes a pointer to an int it was more convenient this way (I believe it used
- more bytes but I no longer know that). There are many others and they all
- save bytes (or at least most of them do if not all). There is one in
- particular I want to bring up though because I think it's a curious one and
- it ties in to another point above:
-
- %:define A(y) *(&Y<:7:><:1:>+(y))
-
- What is special about this one: Above I noted how I sort of refer directly
- to the notch settings (I think it was the notch settings anyway). Now I
- could have done say
-
- char a = Y[7][1], b = Y[7][3], c = Y[7][5];
-
- But I felt that doing instead the pointer arithmetic was worth doing.
- However it used significantly more bytes even as a macro: 17 if I recall
- right. That's with the macro. If I were to include it three times by itself
- it'd be many more. I believe though that when the cpp translates it it still
- requires more thought to determine that a is set to Y[7][1], b to Y[7][3]
- and c to Y[7][5].
-
-
-
-# Obfuscation wrt recode.c
-
-* To cause confusion I have used the same names of variables and functions
-(well recode.c has more functions and variables) but with different meanings.
-For example in recode.c `R` is a `char R[3]` but in prog.c it's `char *R[3]`.
-Another example is where in prog.c `Y` is `char Y[19][27]` in recode.c it's `char
-*Y[3]`. Some are use swaps but not necessarily all. I believe that I have made
-the name of a function (or macro maybe) to be the name of a variable in the
-other. Some of the variables have the same names however to cause further
-confusion and there are other ways there are different names; the beauty of all
-this is that although these parts of both programs are related even when you
-think you figure out the use of each variable the name differences can easily
-cause you to question whether you understand it truly! Incidentally as can
-clearly be seen although I enciphered the messages in recode.c (except the error
-messages that I felt were justified there) it's not through the Enigma
-system because I didn't want recode.c to give many hints as to how prog.c works.
-I don't believe deciphering recode.c will explain how my entry works because
-recode.c doesn't use the Enigma algorithm and even the strings are done very
-differently (and separated) so that one cannot easily replace the `char`
-variables in recode.c, move them to prog.c, compile and expect it to work right.
-
-* Also what is this about ?
-
- /\
- / This is *not* what you think:
- void D(char*x){ /* ... */ }
-
-
- Is that valid and if so how does it function? Yes it's valid but I'll leave
- the other part of the question up to the reader to answer. Hint: you already
- know how it works (yes, really you do)! Another hint: This is and is not a
- misleading comment (conversely this makes this hint both misleading - and
- also not).
diff --git a/2020/ferguson2/recode.html b/2020/ferguson2/recode.html
index afd750344..5e4c71960 100644
--- a/2020/ferguson2/recode.html
+++ b/2020/ferguson2/recode.html
@@ -34,23 +34,30 @@ good chocolate and could use a delicious Double-la
Alternatively if you just want the recipe you could look at my Snake entry
‘Don’t tread on me award’ since it’s also there and not enciphered.
-- What is recode and why is it recommended?
-- Options
- * Protecting against the same I/O file
- * File options parser limitation
- * -R option validation?
-- Piping commands to recode
-- Piping recode to the Enigma simulator
-- Manually test the recode program with the Enigma program
-- Only write config file
-- Reusing a configuration
-- Write config file, read data file and pass to Enigma simulator
-- Piping directly to the Enigma code once (with randomised settings, saved)
-- Usage conclusion
-- Example additions
-- Example uses
-- Delicious Enigma: Double-layered Chocolate Fudge Cake Write config file, read data file and pass to Enigma simulator Piping directly to the Enigma code once (with randomised settings, saved)
+
What is recode and why is it recommended?
diff --git a/2020/ferguson2/recode.text b/2020/ferguson2/recode.text
index 7596de082..bbd6a4c65 100644
--- a/2020/ferguson2/recode.text
+++ b/2020/ferguson2/recode.text
@@ -8,23 +8,40 @@ Alternatively if you just want the recipe you could look at my Snake entry
'Don't tread on me award' since it's also there and not enciphered.
+
- [What is recode and why is it recommended?](#recode)
+
- [Options](#options)
+
* [Protecting against the same I/O file](#samefile)
+
* [File options parser limitation](#fileoptions)
+
* [-R option validation?](#validation)
+
- [Piping commands to recode](#pipingtorecode)
+
- [Piping recode to the Enigma simulator](#pipingtoenigma)
+
- [Manually test the recode program with the Enigma program](#manuallytest)
+
- [Only write config file](#onlyconfig)
+
- [Reusing a configuration](#reuseconfig)
+
- [Write config file, read data file and pass to Enigma simulator](#passtoenigma)
+
- [Piping directly to the Enigma code once (with randomised settings, saved)](#directlytoenigma)
+
- [Usage conclusion](#conclusion)
+
- [Example additions](#additions)
+
- [Example uses](#exampleuses)
+
- [Delicious Enigma: Double-layered Chocolate Fudge Cake](#cake)
+
# What is recode and why is it recommended?
To demonstrate how to and why you should use the recode program with the Enigma