Update polybius

examples/poem.txt.crypt

@@ -1,139 +1 @@
-Ô XFNSY UWêYWJ ! LWFSIJ âRJ ! TM ! OJ YTRGJ à LJSTZC !
+02 03 20 24 00 31 33 00 33 01 13 33 03 24 11 01 23 01 30 14 01 00 30 23 04 01 13 01 24 30 34 42 01 34 24 01 20 22 03 40 03 20 00 01 24 10 30 33 11 01 22 30 24 13 02 30 34 33 02 31 03 33 23 20 24 30 34 02 20 22 24 01 24 03 31 03 02 10 30 23 31 00 22 01 24 30 23 04 33 01 20 22 00 03 20 00 10 01 00 13 01 30 22 01 04 30 24 14 01 34 33 12 22 01 34 33 20 00 20 22 03 10 30 24 02 20 11 33 22 03 10 33 30 20 42 11 01 02 34 02 10 14 33 20 02 00 00 30 34 00 01 33 03 43 30 24 24 03 24 00 01 11 03 24 02 22 30 23 04 33 01 20 22 03 11 20 00 10 01 02 00 22 01 11 20 01 34 11 01 31 33 30 13 33 02 01 00 11 03 23 30 34 33 02 34 02 32 34 20 40 30 20 00 00 30 24 12 33 30 24 00 10 33 30 20 00 40 30 20 33 22 01 12 33 30 24 00 11 34 30 34 33 10 14 33 20 02 00 02 30 34 33 20 00 32 34 20 22 01 33 01 31 30 34 02 02 01 31 34 20 02 32 34 20 22 01 02 00 23 30 33 00 31 30 34 33 24 30 34 02 01 40 01 34 42 23 30 34 33 20 33 31 30 34 33 22 34 20 11 03 24 02 02 30 24 00 30 23 04 01 03 34 11 30 24 00 03 20 22 03 31 20 01 33 33 01 31 30 34 33 03 31 31 34 20 20 22 23 03 31 31 01 22 22 01 11 34 24 01 40 30 20 42 11 30 34 10 01 02 03 11 30 10 00 33 20 24 01 01 02 00 22 01 10 20 01 22 01 24 00 33 30 34 40 01 33 00 31 03 33 22 03 23 03 20 24 10 30 23 23 01 34 24 31 33 01 22 01 24 12 03 24 00 20 22 00 20 01 24 00 22 01 13 01 24 33 01 14 34 23 03 20 24 31 03 33 22 34 20 24 30 34 02 40 20 40 30 24 02 01 00 24 30 34 02 02 30 23 23 01 02 03 34 10 14 01 40 01 00 11 01 02 13 01 22 20 01 33 02 11 30 33 23 03 24 00 11 03 24 02 22 01 34 33 02 23 03 20 02 30 24 02 20 22 11 33 30 04 01 22 01 02 10 22 01 12 02 11 01 00 30 34 00 01 02 22 01 02 31 33 20 02 30 24 02 01 00 23 01 00 01 24 22 20 04 01 33 00 22 01 02 14 30 23 23 01 02 30 33 20 22 01 02 00 22 30 20 24 11 01 24 30 34 02 34 24 01 03 34 00 33 01 14 34 23 03 24 20 00 32 34 20 24 01 22 01 10 30 24 24 03 00 31 30 20 24 00 01 00 11 03 24 02 22 20 24 20 32 34 20 00 33 03 23 31 01 01 24 10 14 03 24 01 01 00 02 30 34 12 12 33 01 01 00 00 30 23 04 01 20 22 02 12 30 24 00 31 30 34 33 00 33 30 34 40 01 33 11 20 01 34 11 01 00 24 04 33 01 34 42 01 12 12 30 33 00 02 20 22 02 02 03 13 20 00 01 24 00 01 24 40 03 20 24 20 22 02 02 30 24 00 10 30 23 23 01 11 01 02 23 30 33 00 02 32 34 20 00 00 01 24 00 22 01 23 34 33 11 01 22 01 34 33 00 30 23 04 01 02 03 24 02 22 30 20 02 03 24 02 04 34 00 02 03 24 02 13 34 20 11 01 20 22 02 01 33 33 01 24 00 20 10 20 04 03 02 20 22 02 02 30 24 00 23 10 14 03 24 00 02 00 03 24 00 20 13 24 30 33 03 24 00 02 20 22 02 24 30 24 00 31 03 02 22 01 34 33 31 03 33 00 11 01 22 03 13 33 03 24 11 01 10 30 24 32 34 00 01 20 33 03 20 31 30 34 33 22 01 02 02 03 34 40 01 33 01 32 34 20 00 00 01 22 01 02 03 20 24 00 22 20 01 34 23 01 02 12 33 33 01 02 01 40 20 01 24 02 40 30 34 02 03 31 31 30 33 00 01 33 23 30 24 11 20 01 34 01 40 20 01 24 02 40 30 34 02 03 31 31 30 33 00 01 33 23 03 00 00 01 31 33 00 33 01 20 22 02 01 02 00 02 30 34 40 01 24 34 10 03 22 23 01 01 24 24 30 02 30 34 33 02 00 33 30 34 04 22 02 11 01 22 03 31 03 33 30 22 01 11 20 00 01 03 34 42 03 31 00 33 01 02 03 22 22 01 44 04 33 03 40 01 44 22 01 02 04 10 14 01 33 02 01 00 22 01 02 10 22 03 20 01 02 01 00 11 01 22 03 11 20 01 34 11 34 10 14 33 20 02 00 03 34 02 34 31 33 23 01 23 30 23 01 24 00 40 20 40 03 24 00 03 20 23 01 44 40 30 34 02 03 20 23 01 44 01 24 40 30 34 02 03 20 23 03 24 00 12 33 33 01 02 40 30 34 02 12 01 33 23 01 33 01 44 23 01 02 31 22 03 20 01 02 20 22 02 01 02 00 11 20 00 32 34 20 22 01 02 00 04 30 24 11 10 22 03 20 33 01 33 11 03 24 02 22 01 34 33 24 34 20 00 10 01 02 31 01 34 31 22 01 02 13 03 33 02 22 30 20 24 11 34 31 33 30 13 33 02 32 34 20 22 34 20 00 11 30 24 00 22 23 01 01 02 00 10 30 34 40 01 33 00 01 11 01 40 30 20 22 01 02 31 34 20 02 20 22 02 01 24 01 02 00 03 22 22 11 03 24 02 22 01 02 40 01 24 00 02 11 03 24 02 22 01 02 12 22 30 00 02 40 01 33 02 22 01 02 24 30 20 33 02 10 14 01 40 03 22 01 00 02 01 00 22 01 02 02 03 24 13 22 03 24 00 02 04 20 22 22 30 00 02 22 01 02 43 01 34 42 12 20 42 02 02 34 33 22 01 02 00 30 20 22 01 02 20 20 10 01 34 42 40 01 33 02 32 34 20 10 01 00 03 31 00 33 01 03 22 22 03 20 00 22 30 24 00 13 30 33 13 20 20 20 30 14 00 03 24 11 20 02 32 34 01 22 04 03 02 14 22 03 02 10 14 01 44 10 01 02 04 03 33 04 03 33 01 02 02 00 03 22 01 22 10 14 03 12 03 34 11 11 01 00 01 02 23 01 23 04 33 01 02 10 14 03 33 13 32 34 01 22 01 04 30 34 33 33 01 03 34 33 03 24 13 01 03 24 00 02 01 02 13 22 03 20 40 01 02 01 00 02 01 02 04 03 33 33 01 02 12 33 30 00 00 01 03 34 13 20 04 01 00 02 30 24 30 24 13 22 01 30 00 30 24 02 03 24 13 02 01 02 00 12 20 13 10 20 01 22 00 03 24 11 20 02 32 34 01 22 01 02 10 14 20 01 24 02 11 03 24 02 10 01 02 03 24 13 40 20 01 24 24 01 24 00 04 30 20 33 01 01 00 32 34 01 22 03 23 30 34 10 14 01 14 30 33 33 20 04 22 01 01 02 02 03 20 23 03 34 40 30 22 30 43 01 34 42 10 30 23 23 01 11 03 24 02 34 24 01 33 34 10 14 01 01 24 00 33 01 01 24 00 03 04 30 34 10 14 01 24 30 20 33 01 01 00 04 30 34 33 11 30 24 24 01 03 34 02 30 22 01 20 22 11 03 24 02 22 01 02 00 33 30 34 02 11 01 0Line truncated
-OJZSJ, NQ FAFNY JSHTW IJ QTSLX OTZWX UFWRN STZX,
-NQ S'JS F UFX HTRUYé QJ STRGWJ ;
-NQ éYFNY à HJY âLJ Tù QJ GTSMJZW KQJZWNY ;
-NQ F HTSXNIéWé QF HWTNC IJ OéXZX-HMWNXY
-YTZYJ WFDTSSFSYJ IFSX Q'TRGWJ.
-
-NQ F INY : — « H'JXY QJ INJZ IJ UWTLWèX JY I'FRTZW.
-OéXZX, VZN ATNY YTS KWTSY HWTNY ATNW QJ KWTSY IZ OTZW.
-HMWNXY XTZWNY à VZN QJ WJUTZXXJ.
-UZNXVZ'NQ JXY RTWY UTZW STZX, OJ AJZC RTZWNW UTZW QZN ;
-IFSX XTS YTRGJFZ, ITSY O'FN QF UNJWWJ UTZW FUUZN,
-NQ R'FUUJQQJ I'ZSJ ATNC ITZHJ.
-
-« XF ITHYWNSJ JXY QJ HNJQ JSYW'TZAJWY ; UFW QF RFNS,
-HTRRJ ZS UèWJ Q'JSKFSY, NQ YNJSY QJ LJSWJ MZRFNS ;
-UFW QZN STZX ANATSX JY STZX XTRRJX ;
-FZ HMJAJY IJX LJôQNJWX ITWRFSY IFSX QJZWX RFNXTSX,
-NQ IéWTGJ QJX HQJKX IJ YTZYJX QJX UWNXTSX
-JY RJY JS QNGJWYé QJX MTRRJX.
-
-« TW NQ JXY, QTNS IJ STZX, ZSJ FZYWJ MZRFSNYé
-VZN SJ QJ HTSSFîY UTNSY, JY IFSX Q'NSNVZNYé
-WFRUJ JSHMFîSéJ, JY XTZKKWJ JY YTRGJ ;
-NQX KTSY UTZW YWTZAJW INJZ IJ YéSéGWJZC JKKTWYX ;
-NQX X'FLNYJSY JS AFNS ; NQX XTSY HTRRJ IJX RTWYX
-VZN YâYJSY QJ RZW IJ QJZW YTRGJ.
-
-« XFSX QTN, XFSX GZY, XFSX LZNIJ, NQX JWWJSY NHN-GFX.
-NQX XTSY RéHMFSYX, éYFSY NLSTWFSYX ; NQX S'TSY UFX
-QJZW UFWY IJ QF LWFSIJ HTSVZêYJ.
-O'NWFN. UTZW QJX XFZAJW OJ VZNYYJ QJ XFNSY QNJZ.
-Ô RJX KWèWJX, OJ ANJSX ATZX FUUTWYJW RTS INJZ,
-OJ ANJSX ATZX FUUTWYJW RF YêYJ ! » —
-
-UWêYWJ, NQ X'JXY XTZAJSZ, HFQRJ JS STX OTZWX YWTZGQéX,
-IJ QF UFWTQJ INYJ FZC FUôYWJX : — FQQJE,
-GWFAJE QJX GûHMJWX JY QJX HQFNJX ! —
-JY IJ Q'FINJZ IZ HMWNXY FZ XZUWêRJ RTRJSY :
-— Ô ANAFSY, FNRJE-ATZX ! FNRJE. JS ATZX FNRFSY,
-KWèWJX, ATZX KJWRJWJE RJX UQFNJX. —
-
-NQ X'JXY INY VZ'NQ JXY GTS I'éHQFNWJW IFSX QJZW SZNY
-HJX UJZUQJX éLFWéX QTNS IZ UWTLWèX VZN QZNY,
-ITSY Q'âRJ JXY HTZAJWYJ IJ ATNQJX ;
-UZNX NQ X'JS JXY FQQé, IFSX QJX AJSYX, IFSX QJX KQTYX,
-AJWX QJX STNWX HMJAFQJYX JY QJX XFSLQFSYX GNQQTYX,
-QJX DJZC KNCéX XZW QJX éYTNQJX.
-
-NN.
-
-HJZC AJWX VZN HJY FUôYWJ FQQFNY, Q'TSY éLTWLé.
-
-NNN.
-
-TM ! YFSINX VZJ Qà-GFX, MéQFX ! HMJE HJX GFWGFWJX,
-X'éYFQJ Q'éHMFKFZI IJ YJX RJRGWJX HMFWLé,
-VZJ QJ GTZWWJFZ, WFSLJFSY XJX LQFNAJX JY XJX GFWWJX,
-KWTYYJ FZ LNGJY XTS TSLQJ Tù YTS XFSL X'JXY KNLé ;
-
-HNJQ ! YFSINX VZJ QJX HMNJSX IFSX HJ XFSL ANJSSJSY GTNWJ,
-JY VZJ QF RTZHMJ MTWWNGQJ, JXXFNR FZ ATQ OTDJZC,
-HTRRJ IFSX ZSJ WZHMJ JSYWJ JS YF GTZHMJ STNWJ
-JY GTZWITSSJ FZ XTQJNQ IFSX QJX YWTZX IJ YJX DJZC ;
-
-YFSINX VZ'éHMJAJQéJ, JY XFSX ATNC, XFSX UFZUNèWJX,
-YF YêYJ GQêRJ JXY Qà XZW ZS NSKâRJ UNJZ,
-QNAWéJ FZC ANQX FKKWTSYX, RJZWYWNJ à HTZUX IJ UNJWWJX,
-NHN, IJWWNèWJ YTN, RFWYDW, TS AJSI YTS INJZ !
-
-HJ INJZ VZN S'JXY VZ'à YTN, RFWYDW, TS YJ QJ ATQJ !
-TS QJ QNAWJ à RFSIWNS, HJ INJZ UTZW VZN YZ RJZWX !
-IJX MTRRJX, HTRRJ YTN WJAêYZX IJ Q'éYTQJ,
-UTZW êYWJ HFWINSFZC, UTZW êYWJ XéSFYJZWX,
-
-IJX UWêYWJX, UTZW FATNW IJX UFQFNX, IJX HFWWTXXJX,
-JY IJX OFWINSX Q'éYé WNFSY XTZX QJ HNJQ GQJZ,
-UTZW FWLJSYJW QJZW RNYWJ JY UTZW ITWJW QJZWX HWTXXJX,
-UTZW GTNWJ IJ GTS ANS, FXXNX UWèX I'ZS GTS KJZ,
-
-FZ KTWGFS ITSY QF RFNS IFSX QJ RJZWYWJ JXY YWJRUéJ,
-FZ QFWWTS HMFWLé I'TW VZN UFDJ JY VZN XTZWNY,
-LWFSI INJZ ! WJYTZWSJ-YTN AJWX STZX, YêYJ HTZUéJ !
-NQX AJSIJSY OéXZX-HMWNXY ! NQX AJSIJSY OéXZX-HMWNXY !
-
-NQX QNAWJSY FZ GFSINY, UTZW VZJQVZJX XFHX XTWINIJX,
-Q'éAFSLNQJ, QF QTN, Q'FZYJQ éUTZAFSYé,
-JY QF OZXYNHJ FZC DJZC XéAèWJX JY HFSINIJX,
-JY Q'éYTNQJ IZ HTJZW MZRFNS, QF AéWNYé !
-
-QJX GTSX OJYéX, ANAFSYX, FZ GFLSJ, TZ RTWYX, FZC KQJZAJX,
-Q'MTRRJ OZXYJ UWTXHWNY UFW HFWYTZHMJ XDQQF,
-Q'NSSTHJSY éLTWLé, QJ IJZNQ XFHWé IJX AJZAJX,
-QJX UQJZWX IJ Q'TWUMJQNS, NQX AJSIJSY YTZY HJQF !
-
-YTZY ! QF KTN, QJ XJWRJSY VZJ INJZ YNJSY XTZX XF LFWIJ,
-QJ XFNSY YJRUQJ Tù, RTZWFSY, YZ INX :NSYWTïGT,
-NQX QNAWJSY YTZY ! UZIJZW, AJWYZ ! — RFWYDW, WJLFWIJ,
-WTZAWJ YJX DJZC VZ'JRUQNY QF QZJZW IZ YTRGJFZ ; —
-
-NQX AJSIJSY Q'FWHMJ FZLZXYJ Tù Q'MTXYNJ éYNSHJQQJ !
-NQX AJSIJSY HMWNXY, YJ INX-OJ ! JY XJX RJRGWJX QNéX !
-NQX AJSIJSY QF XZJZW VZN XZW XTS KWTSY WZNXXJQQJ,
-JY QJX HQTZX IJ XJX RFNSX, JY QJX HQTZX IJ XJX UNJIX !
-
-NQX AJSIJSY FZ GWNLFSI VZN HMJE QZN QJX FYYNWJ
-QJ LWFSI HWZHNKNé XZW QJX MTRRJX UJSHMé ;
-NQX AJSIJSY XF UFWTQJ, NQX AJSIJSY XTS RFWYDWJ,
-JY YTS RFWYDWJ à YTN UFW-IJXXZX QJ RFWHMé !
-
-YFSY UTZW QJX HTZUX IJ KTZJY VZ'NQ WJçZY à QF UTWYJ !
-HéXFW ! YFSY UTZW Q'FRJS, YFSY UTZW Q'FQQéQZNF !
-YFSY UTZW QF UNJWWJ Tù ANSY MJZWYJW XF YêYJ RTWYJ !
-YFSY UTZW QJ IWFU WTZLN VZJ XF GFWGJ JXXZDF !
-
-NQX AJSIJSY XJX LJSTZC RJZWYWNX, XF UFQRJ AJWYJ,
-XF UQFNJ FZ KQFSH, XTS TJNQ YTZY GFNLSé I'NSKNSN,
-XJX UQJZWX, XTS FLTSNJ, JY XF GTZHMJ JSYWTZAJWYJ,
-JY QJ HWN VZ'NQ UTZXXF : QFRRF XFGFHYMFSN !
-
-NQX AJSIJSY QJ XéUZQHWJ ! NQX AJSIJSY QJX YéSèGWJX !
-QJX XéWFUMNSX HMFSYFSY FZ XJZNQ UWTKTSI IJX HNJZC,
-JY QF RèWJ IJGTZY XTZX Q'FWGWJ FZC GWFX KZSèGWJX,
-VZN, XJSYFSY Qà XTS KNQX, SJ QJAFNY UFX QJX DJZC !
-
-TZN, HJX éAêVZJX, TZN, HJX RFWHMFSIX, TZN, HJX UWêYWJX
-F Q'MNXYWNTS IZ HWNRJ, FXXTZAN, HTZWTSSé,
-F HJ SéWTS WJUZ VZN WNY UFWRN QJX YWFîYWJX,
-ZS UNJI XZW YMWFXéFX, ZS HTZIJ XZW UMWDSé,
-
-FZ ATQJZW VZN YZF QJX QTNX à HTZUX IJ HWTXXJ,
-FZ UNWFYJ JRUJWJZW SFUTQéTS IJWSNJW,
-NAWJ IJZC KTNX, NRRTSIJ JSHTW UQZX VZJ KéWTHJ,
-UTZWHJFZ IFSX QJ HQTFVZJ JY QTZU IFSX QJ HMFWSNJW,
-
-NQX AJSIJSY, ô RFWYDW, QJ INJZ UJSXNK JY UâQJ
-VZN, IJGTZY XZW QF YJWWJ JY XTZX QJ KNWRFRJSY,
-YWNXYJ JY STZX XTZWNFSY IFSX STYWJ SZNY KFYFQJ,
-XZW QJ STNW LTQLTYMF XFNLSJ éYJWSJQQJRJSY !

examples/sonnet116.txt

@@ -0,0 +1,16 @@
+Let me not to the marriage of true minds
+Admit impediments. Love is not love
+Which alters when it alteration finds,
+Or bends with the remover to remove:
+O no! it is an ever-fixed mark
+That looks on tempests and is never shaken;
+It is the star to every wandering bark,
+Whose worth’s unknown, although his height be taken.
+Love’s not Time’s fool, though rosy lips and cheeks
+Within his bending sickle’s compass come:
+Love alters not with his brief hours and weeks,
+But bears it out even to the edge of doom.
+If this be error and upon me proved,
+I never writ, nor no man ever loved. 
+
+William Shakespeare

exec.sh

@@ -1,3 +1,3 @@
 #!/bin/sh
 
-gcc -Wall src/main.c src/functions.c src/caesar.c src/vigenere.c -o output/main && ./output/main $1 $2 $3 $4
+gcc -Wall src/main.c src/functions.c src/caesar.c src/vigenere.c src/polybius.c -o main && ./main $1 $2 $3 $4

src/caesar.c

@@ -1,31 +1,6 @@
 #include "caesar.h"
 
-#define BUFFER_SIZE 128
 
-/*
- This function read the file block by block until the end of it
- */
-int readFile(FILE *f, int *size, char *buffer){
-    int index = 0;
-    char c;
-    int end = 0;
-
-    do{
-        c = fgetc(f);
-        buffer[index] = c;
-        index++;
-        *size += 1;
-
-        // End of the file, we stop it
-        if (c == EOF){
-            buffer[index - 1] = '\0';
-            index = BUFFER_SIZE;
-            end = 1;
-        }
-    }while(index < BUFFER_SIZE);
-
-    return end;
-}
 /*
 	s -> path source
 	d -> path destination

src/caesar.h

@@ -6,7 +6,6 @@
 #include "functions.h"
 
 /* Functions */
-int foo(FILE *, int *, char *);
 int cryptCaesar(const char *, const char *, const int);
 int decryptCaesar(const char *, const char *, const int);
 

src/functions.c

@@ -12,12 +12,35 @@ int fileExist(const char *path) {
 	FILE *f=NULL;
 	f=fopen(path,"r");
 
-	if(f==NULL){
+	if(f==NULL)
 		return -1;
-	}
 	fclose(f);
 	return 0;
 }
+/*
+ This function read the file block by block until the end of it
+ */
+int readFile(FILE *f, int *size, char *buffer){
+    int index = 0;
+    char c;
+    int end = 0;
+
+    do{
+        c = fgetc(f);
+        buffer[index] = c;
+        index++;
+        *size += 1;
+
+        // End of the file, we stop it
+        if (c == EOF){
+            buffer[index - 1] = '\0';
+            index = BUFFER_SIZE;
+            end = 1;
+        }
+    }while(index < BUFFER_SIZE);
+
+    return end;
+}
 /*
 	path -> path source
 	This function copy all characters of the file in the buffer

src/functions.h

@@ -5,8 +5,11 @@
 #include <stdlib.h>
 #include <string.h>
 
+#define BUFFER_SIZE 4096
+
 /* Functions */
 void usage();
+int readFile(FILE *, int *, char *);
 int fileExist(const char *path);
 int copyFile(const char *path, char *buffer);
 int addDataToFile(const char *data, const char *path);

src/main.c

@@ -1,6 +1,7 @@
 #include "functions.h"
 #include "caesar.h"
 #include "vigenere.h"
+#include "polybius.h"
 
 int main(int argc, char *argv[]) {
     int error = 0;
@@ -14,7 +15,7 @@ int main(int argc, char *argv[]) {
     }
 
     // Check kind of encryption
-    for(i = 0; i < 3; i++){
+    for(i = 0; i < 4; i++){
         if(strcmp(argv[1], options[i]) == 0)
             error++;
     }
@@ -100,7 +101,24 @@ int main(int argc, char *argv[]) {
     }
     // Polybius square
     else if(strcmp(argv[1], "-s") == 0){
+        char key[26];
+        int res;
 
+        printf("Your key: ");
+        scanf("%s", key);
+
+        if (strlen(key) > 26){
+            printf("Your key is too big. Choose a small one\n");
+            return -1;    
+        }
+
+        if(strcmp(hook, "crypt") == 0)
+            res = cryptPolybius(fileSrc, fileDst, key);
+        else
+            res = decryptPolybius(fileSrc, fileDst, key);
+
+        if (res != 0)
+            printf("Failed to crypt/decrypt the file\n");
     }
 
     /* Display error */
@@ -111,7 +129,5 @@ int main(int argc, char *argv[]) {
      */
 
     free(fileDst);
-    //free(buffer);
-    //free(data);
     return 0;
 }

src/polybius.c

@@ -0,0 +1,174 @@
+#include "polybius.h"
+
+
+int cryptPolybius(const char *filenameSrc, const char *filenameDst, const char *key){
+    char polybius[POLYBIUS_SIZE][POLYBIUS_SIZE];
+    FILE *f = NULL, *fDst = NULL;
+    char data[BUFFER_SIZE];
+    char dataEncrypted[BUFFER_SIZE];
+    int size = 0, end = 0, i = 0, j = 0;
+    char c = 0;
+
+    generateSquarePolybius(polybius, key);
+
+    for (i = 0; i < POLYBIUS_SIZE; i++){
+        for (j = 0; j < POLYBIUS_SIZE; j++)
+            printf("%c ", polybius[i][j]);
+        printf("\n");
+    }
+    // Open the file
+    f = fopen(filenameSrc, "r+");
+    if (f == NULL) return -1;
+
+    fDst = fopen(filenameDst, "w");
+    if (fDst == NULL) {
+        fclose(f);
+        return -1;
+    }
+    do {
+        end = readFile(f, &size, data);
+
+	    /********* Encryption **********/
+        for (i = 0; i < size; i++){
+            if (data[i] >= 'a' && data[i] <= 'z')
+                c = data[i] - 32;
+            else c = data[i];
+
+            for (j = 0; j < POLYBIUS_SIZE; j++){
+                for (int x = 0; x < POLYBIUS_SIZE; x++){
+                    if (c == polybius[j][x]){
+                       fputc(j + '0', fDst);
+                       fputc(x + '0', fDst);
+                    }
+                }
+            }
+            if (c == '\n' || c == ' '){
+                fputc(c, fDst);
+                fputc(0, fDst); // For having a couple of number
+            }
+        }
+
+        size = 0; 
+        memset(data, 0, BUFFER_SIZE);
+        memset(dataEncrypted, 0, BUFFER_SIZE);
+    }while(end != 1);
+
+	/* Close files */
+    fclose(f);
+    fclose(fDst);
+    return 0;
+}
+int decryptPolybius(const char *filenameSrc, const char *filenameDst, const char *key){
+    char polybius[POLYBIUS_SIZE][POLYBIUS_SIZE];
+    FILE *f = NULL, *fDst = NULL;
+    char data[BUFFER_SIZE];
+    char dataEncrypted[BUFFER_SIZE];
+    int size = 0, end = 0, i = 0, j = 0;
+
+    generateSquarePolybius(polybius, key);
+
+    for (i = 0; i < POLYBIUS_SIZE; i++){
+        for (j = 0; j < POLYBIUS_SIZE; j++)
+            printf("%c ", polybius[i][j]);
+        printf("\n");
+    }
+    // Open the file
+    f = fopen(filenameSrc, "r+");
+    if (f == NULL) return -1;
+
+    fDst = fopen(filenameDst, "w");
+    if (fDst == NULL) {
+        fclose(f);
+        return -1;
+    }
+    do {
+        end = readFile(f, &size, data);
+
+	    /********* Decryption **********/
+        for (i = 0; i < size; i += 2){
+            if (data[i] >= 48 && data[i] <= 53) {
+                int c1 = data[i] - '0';
+                int c2 = data[i+1] - '0';
+                char c = polybius[c1][c2];
+                printf("%c", c);
+                fputc(c, fDst);
+            }
+            else{
+                printf("%c", data[i]);
+                fputc(data[i], fDst);
+            }
+        }
+
+        size = 0; 
+        memset(data, 0, BUFFER_SIZE);
+        memset(dataEncrypted, 0, BUFFER_SIZE);
+    }while(end != 1);
+
+	/* Close files */
+    fclose(f);
+    fclose(fDst);
+    return 0;
+
+}
+/*
+ This function fill the polybius square
+ */
+static void fillSquare(int pos, int *posPolybius, char *p, char polybius[POLYBIUS_SIZE][POLYBIUS_SIZE]){
+    for (int i = 0; i < POLYBIUS_SIZE; i++){
+        polybius[pos][i] = p[*(posPolybius)];
+        *posPolybius = *posPolybius + 1;
+    }
+}
+static int findKeyInSquare(const char *polybius, char c){
+    // We exclude the 'J' character
+    for (int i = 0; i < ALPHABET_SIZE - 1; i++)
+        if (c == polybius[i])
+            return 1;
+    return 0;
+}
+/*
+ This function generate the polybius square
+ */
+void generateSquarePolybius(char polybius[POLYBIUS_SIZE][POLYBIUS_SIZE], const char *key){
+    char a[ALPHABET_SIZE - 1] = {0}; // The size is 25, we exclude the J character
+
+    int pos = 0;
+    for (int i = 0; i < strlen(key); i++){
+        char k;
+        if (key[i] >= 'a' && key[i] <= 'z')
+            k = key[i] - 32; // 32 = 26 + special characters
+        else k = key[i];
+        int res = findKeyInSquare(a, k);
+        if (res == 0)
+            a[pos++] = k;
+    }
+    int n = 0;
+    int t = pos;
+    for (int i = pos; i < ALPHABET_SIZE + pos; i++){
+        char c = 'A' + n;
+        if (c == 'J'){
+            // We check if I is in the array, if yes, we do not add it
+        }
+        /*if (c == 'I'){
+            // We check if J is in the array, is yes, we do not add it
+            int res = findKeyInSquare(a, 'J');
+            // J not in the array, we add it
+            if (res == 0){
+                a[t++] = 'A';
+            }
+        }*/
+        if (c != 'J'){
+            int res = findKeyInSquare(a, c);
+
+            if (res == 0)
+                a[t++] = c;
+        }
+        n++;
+    }
+    pos = 0;
+    fillSquare(0, &pos, a, polybius);     
+    fillSquare(1, &pos, a, polybius);     
+    fillSquare(2, &pos, a, polybius);     
+    fillSquare(3, &pos, a, polybius);     
+    fillSquare(4, &pos, a, polybius);     
+}

src/polybius.h

@@ -0,0 +1,15 @@
+#ifndef H_POLYBIUS
+#define H_POLYBIUS
+
+#include <stdio.h>
+#include <string.h>
+#include "functions.h"
+
+#define POLYBIUS_SIZE 5
+#define ALPHABET_SIZE 26
+
+int cryptPolybius(const char *, const char *, const char *);
+int decryptPolybius(const char *, const char *, const char *);
+void generateSquarePolybius(char polybius[5][5], const char *);
+
+#endif