Attempt of solution for week1 Crypto

gistfile1.py

#!/usr/bin/python

import sys
import pprint
from copy import deepcopy

def insert_delims(string, every=64):
    return ' '.join(string[i:i+every] for i in xrange(0, len(string), every))
def XorTwoHexStrings(inp_str1, inp_str2):
    if (len(inp_str1)!=len(inp_str2)):
        print len(inp_str1),'!=',len(inp_str2)
        return 0;
    final_string="";
    for i in xrange(0, len(inp_str1)):
        TmpRez = hex(int (inp_str1[i],16) ^ int (inp_str2[i],16)).replace('0x','');
        final_string+=TmpRez;
        #print inp_str1[i], '^', inp_str2[i], '=', TmpRez;
    return final_string;
    #inp_str1 - string; inp_str2 - strng; returns string
    
def ConvertStrtoHex(inp_str1):
    #inp_str1 - string; returns string
    rez_str="";
    for i in inp_str1:
        rez_str+=hex(ord(i)).replace('0x','')
    return rez_str
#obtaining input data from text file. returns python-specific list with data: first sublist contains ciphered texts and second sublist contains text to decipher
def read_data():
    f=open('t2_input.txt', 'r');
    rez=[];
    rez.append([]);
    rez.append([]);
    sum=0;
    for line in f:
        sum+=1;
        if (sum % 2 == 0):
            rez[0].append(line[:-1]);
            print len(rez[0][-1]);
    tmpstr = rez[0].pop();
    rez[1].append(tmpstr);
    return rez;
def space_xor_symbols(file2write):
    #file2write should be opened
    space_sym=' ';
    file2write.write('<h3> XOR space with other symbols </h3>');
    #xor space with a-z
    sym='a';
    while (sym!='z'):
        #b=XorTwoHexStrings(space_sym, sym);
        b=XorTwoHexStrings(ConvertStrtoHex(space_sym), ConvertStrtoHex(sym));
        file2write.write('\''+space_sym+'\''+' xor '+'\''+sym+'\' = '+b+'<br>');
        sym=chr(ord(sym)+1);
    
def print_detailed_table(file2write, inplist):
    file2write.write("<table border=\"1\">");
    file2write.write("<tr> <td> &nbsp; </td> <td> &nbsp; </td>"); 
    cntr=0; 
    while (cntr<len(inplist[0][2])/2):
        file2write.write("<td>"+str(cntr+1)+"</td>"+"<td>"+str(cntr+2)+"</td>");
        cntr+=2;
    file2write.write("</tr>");
    for harr in inplist: 
        file2write.write("<tr>");
        file2write.write("<tr> <td>"+str(harr[0]+1)+"</td> <td>"+str(harr[1]+1)+"</td>");
        cntr=0;
        while (cntr<len(harr[2])):
            file2write.write("<td>"+harr[2][cntr]+harr[2][cntr+1]);
            if (((harr[2][cntr]+harr[2][cntr+1]).decode('hex')>='A') and ((harr[2][cntr]+harr[2][cntr+1]).decode('hex')<='Z')):
                file2write.write("<br> <span style=\'background-color:salmon\'> \'"+(harr[2][cntr]+harr[2][cntr+1]).decode('hex')+"\' </span>")
            elif (((harr[2][cntr]+harr[2][cntr+1]).decode('hex')>='a') and ((harr[2][cntr]+harr[2][cntr+1]).decode('hex')<='z')):
                file2write.write("<br> <span style=\"background-color:salmon\"\'> \'"+(harr[2][cntr]+harr[2][cntr+1]).decode('hex')+"\' </span>")
            else:
                file2write.write("<br> &nbsp; &nbsp; &nbsp; ")
            file2write.write("</td>");
            cntr+=2;
        file2write.write("</tr>");
    file2write.write("</table>")
def encrypt_heuristics(InpList, LogDaFile, num_cryptorows):
    #takes full InpList and returns List with partially encrypted plaintext messages 
    #for each byte in cryptomessage... fixing second number in pair and checking the symbols in cyphertexts 
    plaintxtmsgs=[];
    for i in InpList:
        plaintxtmsgs.append([]);
    #for each byte in cryptomessage...
    chrplace=0; cntr=0;
    while (chrplace < len(InpList[0][2])):
        firstnum=-1;
        #secondnum=0;
        numberfound=0;
        symogrp_found=[];
        LogDaFile.write("<p> ==== Character: "+str(cntr)+" ==== </p>");
        #for rcrd1 in InpList:
        #    numberfound=0;
        #    for rcrd2 in InpList:
        #        if (rcrd2[1]==rcrd1[1]):
        #            LogDaFile.write("<p> now processing: "+str(rcrd2[0]+1)+";"+str(rcrd2[1]+1)+" </p>")
        #    if (numberfound==-1):
        #        break;
        #i am not sure to start iterating from 1 or from 0...
        found=False
        for c1 in range(0, num_cryptorows):
            noalpha=0;
            symbolsofgroup=[]; #crutch essentially
            #firstnum=-1
            LogDaFile.write("<div style=\'color:blue\'> >>> Processing group for "+str(c1+1)+"</div>");
            for rcrd2 in InpList:
                if ((rcrd2[0]==c1) or (rcrd2[1]==c1)):
                    LogDaFile.write("<p> now processing: "+str(rcrd2[0]+1)+";"+str(rcrd2[1]+1)+" ("+(rcrd2[2][chrplace]+rcrd2[2][chrplace+1]).decode('hex')+")");
                    symbolsofgroup.append((rcrd2[2][chrplace]+rcrd2[2][chrplace+1]).decode('hex'));
                    if (((rcrd2[2][chrplace]+rcrd2[2][chrplace+1]).decode('hex').isalpha()  )==False): 
                        noalpha+=1;
                        LogDaFile.write(" //NOT A NUMERIC! </p>");
            if (noalpha<=1):
                #found!
                #print "found!"
                firstnum=c1;
                found=True;
                symogrp_found=symbolsofgroup;
                break;
        LogDaFile.write("<div style=\'color:red\'> Message "+str(c1+1)+" has space at "+str(cntr)+"</div>");
        if (found==False):
            LogDaFile.write("<div style=\'color:red\'> Nothing found... </div>")
            for i in range(len(plaintxtmsgs)):
                plaintxtmsgs[i].append('?');
        else: #decrypt what do we have
            print "go decrypting! ( Row with space:"+str(firstnum)+")";
            #we already know that message c1 (firstnum) has 'space' in cntr position. and other symbols might be obtained by xoring space to obtained alphanumerics
            plaintxtmsgs[firstnum].append(' ');
            for rcrd2 in InpList:
                if ((rcrd2[0]==firstnum) and (rcrd2[1]!=firstnum)):
                    plaintxtmsgs[rcrd2[1]].append(chr(ord(' ') ^ ord((rcrd2[2][chrplace]+rcrd2[2][chrplace+1]).decode('hex'))));
                elif ((rcrd2[1]==firstnum) and (rcrd2[0]!=firstnum)): 
                    plaintxtmsgs[rcrd2[0]].append(chr(ord(' ') ^ ord((rcrd2[2][chrplace]+rcrd2[2][chrplace+1]).decode('hex'))));
        chrplace+=2;
        cntr+=1;
    for line in plaintxtmsgs:
        LogDaFile.write("<br>")
        for chr2 in line:
            LogDaFile.write(chr2);
    return plaintxtmsgs;
def process_data(InpDataList):
    #Saving List (we don't need InpDataList to be modified)
    Data2Process = deepcopy(InpDataList);
    
    #Find the maximal message len
    maxlen=0;
    for line in Data2Process[0]:
        if len(line)>maxlen:
            maxlen = len(line);
    #We are going to 'align' all messages (complete 'em  to the longest string with zeros)
    indx=0;
    for line in Data2Process[0]:
        for i in range(0, abs(len(line)-maxlen)):
            Data2Process[0][indx]+='0';
        #print Data2Process[0][indx];
        indx+=1;
    #XOR all obtained lines...
    f2=open('t2_results.html','w');
    f2.write('<html> <title> XOR results </title> ');
    f2.write('<body>');
    f2.write('<div id=\"myID\" style=\"width:1600px; font-family:Courier New">');
    f2.write('<table border="1" width="1600px">');
    f2.write('<tr> <th> Arg1 </th> <th> (num) </th> <th> Arg2 </th> <th> (num) </th> <th> result </th> </tr>');
    cntr1=0;
    cntr2=0;
    xor_rezlst=[];
    while (cntr1<len(Data2Process[0])):
        cntr2=cntr1+1;
        while (cntr2<len(Data2Process[0])):
            #xor is a symmetrical operation, so order of arguments does not matter
            tmprez = XorTwoHexStrings(Data2Process[0][cntr1], Data2Process[0][cntr2]);
            xor_rezlst.append([cntr1, cntr2, tmprez]);
            f2.write('<tr> <td>'+insert_delims(Data2Process[0][cntr1], 8)+'</td><td>'+str(cntr1)+'</td><td>'+insert_delims (Data2Process[0][cntr2], 8)+'</td>'+'<td>'+str(cntr2)+'</td>'+'<td>'+insert_delims(tmprez, 8)+'</td> </tr>');
            cntr2+=1;
        cntr1+=1;
    
    #f2.write();
    f2.write('</table>');
    f2.write('<h3> XOR results (brief) </h3>')
    for line in xor_rezlst:
        f2.write('<p>'+line[2]+'</p>');
    space_xor_symbols(f2);
    #printing the table with xored data
    
    print_detailed_table(f2, xor_rezlst);
    final_msgs = encrypt_heuristics(xor_rezlst, f2, len(Data2Process[0]));
    f2.write('</div>')
    #f2.write('<script language=\'JavaScript\'> w=screen.width; d=document.getElementById(\'myID\'); d.style.width=w; </script>')
    f2.write('</body>');
    f2.write('</html>');
        
    return final_msgs;
    
def main():
    SomeRez = read_data();
    pp=pprint.PrettyPrinter(indent=4);
    #SomeRez[0].insert(0,SomeRez[1][0]);
    SomeRez[0].append(SomeRez[1][0]);
    print '=== Obtained Data ===';
    pp.pprint(SomeRez);
    print '=====================';
    rez=process_data(SomeRez);
    print len(SomeRez);
    print('Your results!');
    
    return 0;
if __name__ == '__main__':
    main();