Simple encryption algorithm

[Phat Looser]

Since I do not remember any secure hashing or encryption algorithms in LUA, I made one myself, based on the idea of the blowfish algorithm (but less complicated).

iaEncryptionArray = {}; 
iaDecryptionArray = {}; 
caPassword = ""; 
caPasswordLength = 0; 
caText = ""; 
caEncryptedText = ""; 
iPasswordPosition = 1; 
  
function addEncryptionPasswordChar(value) 
    iPasswordPosition = iPasswordPosition + 1; 
    if (iPasswordPosition > caPasswordLength) then 
        iPasswordPosition = 1; 
    end 
    output = value + string.byte(caPassword,position); 
    if (output > 999) then 
        output = output - 1000; 
    end 
    return output; 
end 
  
function subsEncryptionPasswordChar(value) 
    iPasswordPosition = iPasswordPosition + 1; 
    if (iPasswordPosition > caPasswordLength) then 
        iPasswordPosition = 1; 
    end 
    output = value - string.byte(caPassword,position); 
    if (output < 0) then 
        output = output + 1000; 
    end 
    return output; 
end 
  
function generateEncryptionPassword() 
    iPasswordHash = 0; 
    caOutput = ""; 
    for i=1, caPasswordLength, 1 do 
        iPasswordHash = iPasswordHash + string.byte(caPassword,i); -- char! 
    end 
    for i=1, caPasswordLength, 1 do 
        caOutput = caOutput .. string.char(iPasswordHash % string.byte(caPassword,i)); -- char! char! 
    end 
    return caOutput; 
end 
  
function stringSetChar(string,char,pos) 
    length = string.len(string); 
    if pos > length then 
        return string; 
    end 
    string = string.sub(string,1,pos) .. char .. string.sub(string,pos+1,length); 
    return string; 
end 
  
function generateEncryptionArray() 
    generateDecryptionArray(); 
end 
  
function generateDecryptionArray() 
    caEncryptionPassword = generateEncryptionPassword(caPassword); 
    for i=0, 999, 1 do 
        iaEncryptionArray[i]=NIL; 
    end 
    iPosition = 0; 
    n=1; 
    for i=0, 999, 1 do 
        n = n + 1; 
        if (string.byte(caPassword,n) == NIL) then 
            n=1; 
        end 
        iPosition = iPosition + string.byte(caEncryptionPassword,n) + string.byte(caPassword,n); 
        iPosition = iPosition % 1000; 
        while (iaEncryptionArray[iPosition]) do 
            iPosition = iPosition + 1; 
            if (iPosition >= 1000) then 
                iPosition = iPosition - 1000; 
            end 
        end 
        iaEncryptionArray[iPosition] = i; 
        iaDecryptionArray[i] = iPosition; 
    end 
end 
  
function encrypt() 
    generateEncryptionArray(); 
    iTextSize = string.len(caText); 
    iEncryptedTextSize = iTextSize*3; 
    caEncryptedText = ""; 
    aEncryptedText = {}; 
    iPasswordPosition = 1; 
    for i=1, iTextSize, 1 do 
        value = string.byte(caText,i); 
        n=i*3; 
        if (value < 10) then 
            value = string.format("00%i",value); 
        elseif (value < 100) then 
            value = string.format("0%i",value); 
        else 
            value = string.format("%i",value); 
        end 
        aEncryptedText[(i-1)*3+1] = string.byte(value,1) - 48; 
        aEncryptedText[(i-1)*3+2] = string.byte(value,2) - 48; 
        aEncryptedText[(i-1)*3+3] = string.byte(value,3) - 48; 
    end 
    for i=1,iEncryptedTextSize,1 do 
        caEncryptedText = caEncryptedText .. string.format("%i",aEncryptedText[i]); 
    end 
    for runs=1, 32, 1 do 
        for i=1, iEncryptedTextSize, 1 do 
            pos1 = i; 
            pos2 = i+1; 
            pos3 = i+2; 
            if (pos2 > iEncryptedTextSize) then 
                pos2 = pos2 - iEncryptedTextSize; 
                pos3 = pos3 - iEncryptedTextSize; 
            elseif (pos3 > iEncryptedTextSize) then 
                pos3 = pos3 - iEncryptedTextSize; 
            end 
            h = aEncryptedText[pos1]; 
            z = aEncryptedText[pos2]; 
            e = aEncryptedText[pos3]; 
            value = 100*h + 10*z + e; 
            value = iaEncryptionArray[value]; 
            value = subsEncryptionPasswordChar(value,i); 
            h = math.floor(value / 100); 
            value = value - 100*h; 
            z = math.floor(value / 10); 
            value = value - 10*z; 
            e = value; 
            aEncryptedText[pos1] = h; 
            aEncryptedText[pos2] = z; 
            aEncryptedText[pos3] = e; 
        end 
    end 
    caEncryptedText = ""; 
    for i=1,iEncryptedTextSize,1 do 
        caEncryptedText = caEncryptedText .. string.format("%i",aEncryptedText[i]); 
    end 
end 
  
function decrypt() 
    generateDecryptionArray(); 
    iEncryptedTextSize = string.len(caEncryptedText); 
    aEncryptedText = {}; 
    for i=1,iEncryptedTextSize,1 do 
        aEncryptedText[i] = string.byte(caEncryptedText,i) - 48; 
    end 
    caEncryptedText = ""; 
    iPasswordPosition = 1; 
    for runs=1, 32, 1 do 
        for i=iEncryptedTextSize, 1, -1 do 
            pos1 = i; 
            pos2 = i+1; 
            pos3 = i+2; 
            if (pos2 > iEncryptedTextSize) then 
                pos2 = pos2 - iEncryptedTextSize; 
                pos3 = pos3 - iEncryptedTextSize; 
            elseif (pos3 > iEncryptedTextSize) then 
                pos3 = pos3 - iEncryptedTextSize; 
            end 
            h = aEncryptedText[pos1]; 
            z = aEncryptedText[pos2]; 
            e = aEncryptedText[pos3]; 
            value = 100*h + 10*z + e; 
            value = addEncryptionPasswordChar(value,i); 
            value = iaDecryptionArray[value]; 
            h = math.floor(value / 100); 
            value = value - 100*h; 
            z = math.floor(value / 10); 
            value = value - 10*z; 
            e = value; 
            aEncryptedText[pos1] = h; 
            aEncryptedText[pos2] = z; 
            aEncryptedText[pos3] = e; 
        end 
    end 
    iTextSize = iEncryptedTextSize / 3 
    caText = ""; 
    for i=1,iEncryptedTextSize,1 do 
        caEncryptedText = caEncryptedText .. string.format("%i",aEncryptedText[i]); 
    end 
    for i=1, iTextSize, 1 do 
        n = (i-1)*3+1; 
        char = aEncryptedText[n]*100 + aEncryptedText[n+1]*10 + aEncryptedText[n+2]; 
        if char > 255 then 
            caText = "wrong password!"; 
            return; 
        end 
        caText = caText .. string.char(char); 
    end 
end 
  
function encryptString(caTextInput,caPasswordInput) 
    caText = caTextInput; 
    caPassword = caPasswordInput; 
    caPasswordLength = string.len(caPassword); 
    encrypt(); 
    return (caEncryptedText); 
end 
  
function decryptString(caTextInput,caPasswordInput) 
    caEncryptedText = caTextInput; 
    caPassword = caPasswordInput; 
    caPasswordLength = string.len(caPassword); 
    decrypt(); 
    return (caText); 
end 
  
verschl = encryptString("Test","Password"); 
plaintext = decryptString(verschl,"Password"); 
print(addEncryptionPasswordChar(subsEncryptionPasswordChar(1,1),1)); 
print(plaintext); 

The only problem about it is that the output is three times larger then the input, since I found no way of doing a bitwise operations in LUA.

Using this algorithm i encrypted:

A simple LUA encryption

to:

888953271697817971988875429150003339473916115385183229145025698478333

and

123 test

to

589213431067573308035761

and

1234567890

to

599957627210660816794255945607

and

abcdefghijklmnopqrstuvwxyz

to

363695469390506373834224316510624908352602626076666225352477454426305393478617

The password is 7 chars long.

The algorithm is known, the plain text is known, if you are able to find out the password, I consider this algorithm to be a failure.

[Willy]

is md5 not good enough? for dp2.3 i'm pretty sure there was a module, and for 1.0 there are functions built into MTA.

[Phat Looser]

is md5 not good enough? for dp2.3 i'm pretty sure there was a module, and for 1.0 there are functions built into MTA.

MD5 is not an encryption algorithm.

Also, I just did it. There was no reason for doing it except doing it.

[darkdreamingdan]

So where's this encrypted version of the 7 char length password, that you want us to decrypt?

[Phat Looser]

So where's this encrypted version of the 7 char length password, that you want us to decrypt?

with that secret password i encrypted:

A simple LUA encryption

to:

888953271697817971988875429150003339473916115385183229145025698478333

and

123 test

to

589213431067573308035761

and

1234567890

to

599957627210660816794255945607

and

abcdefghijklmnopqrstuvwxyz

to

363695469390506373834224316510624908352602626076666225352477454426305393478617

I just want you to BREAK the algorithm.

All of these lines use the same password.

If you want to encrypt/decrypt something yourself, be sure to use ASCII text and an ASCII password.

# verschl = encryptString("Test","Password");

# plaintext = decryptString(verschl,"Password");

I tested it with random text several times.

When you find out the password (which is 7 chars in size), my algorithm fails (plain text attack).

Imagining storing data client side and having the client find out the decryption password, i.e. by saving its position at a specified place!

I know the password by heart, so, if you want me to encrypt MOAR, then I'll do it.

I also have this algorithm in C, so, if you want to have the sourcecode for that, I should be able to provide it (even though i changed some things in the LUA sourcecode, i.e. adding the password in every step of the encryption).

Edit:

I found out there may be a bug.

The reason is the "iPasswordPosition" integer.

This bug should be solved easily.

Edit2:

Even though there is a "bug", it works, and I have no idea why.

iPasswordPosition is set to 1 every time.

Then, it is increased.

Why the hack does it decrypt the same way it encrypts and still work?

[Phat Looser]

Sorry for double posting, sorry for failing so hard:

I made a mistake in the implementation.

The password wasn't added (line 15 and line 27)

  
iaEncryptionArray = {}; 
iaDecryptionArray = {}; 
caPassword = ""; 
iPasswordLength = 0; 
caText = ""; 
caEncryptedText = ""; 
iPasswordPosition = 1; 
  
function addEncryptionPasswordChar(value) 
    iPasswordPosition = iPasswordPosition + 1; 
    if (iPasswordPosition > iPasswordLength) then 
        iPasswordPosition = 1; 
    end 
    output = value + string.byte(caPassword,iPasswordPosition); 
    if (output > 999) then 
        output = output - 1000; 
    end 
    return output; 
end 
  
function subsEncryptionPasswordChar(value) 
    iPasswordPosition = iPasswordPosition - 1; 
    if (iPasswordPosition < 1) then 
        iPasswordPosition = iPasswordLength; 
    end 
    output = value - string.byte(caPassword,iPasswordPosition); 
    if (output < 0) then 
        output = output + 1000; 
    end 
    return output; 
end 
  
function generateEncryptionPassword() 
    iPasswordHash = 0; 
    caOutput = ""; 
    for i=1, iPasswordLength, 1 do 
        iPasswordHash = iPasswordHash + string.byte(caPassword,i); -- char! 
    end 
    for i=1, iPasswordLength, 1 do 
        caOutput = caOutput .. string.char(iPasswordHash % string.byte(caPassword,i)); -- char! char! 
    end 
    return caOutput; 
end 
  
function stringSetChar(string,char,pos) 
    length = string.len(string); 
    if pos > length then 
        return string; 
    end 
    string = string.sub(string,1,pos) .. char .. string.sub(string,pos+1,length); 
    return string; 
end 
  
function generateEncryptionArray() 
    generateDecryptionArray(); 
end 
  
function generateDecryptionArray() 
    caEncryptionPassword = generateEncryptionPassword(caPassword); 
    for i=0, 999, 1 do 
        iaEncryptionArray[i]=NIL; 
    end 
    iPosition = 0; 
    n=1; 
    for i=0, 999, 1 do 
        n = n + 1; 
        if (string.byte(caPassword,n) == NIL) then 
            n=1; 
        end 
        iPosition = iPosition + string.byte(caEncryptionPassword,n) + string.byte(caPassword,n); 
        iPosition = iPosition % 1000; 
        while (iaEncryptionArray[iPosition]) do 
            iPosition = iPosition + 1; 
            if (iPosition >= 1000) then 
                iPosition = iPosition - 1000; 
            end 
        end 
        iaEncryptionArray[iPosition] = i; 
        iaDecryptionArray[i] = iPosition; 
    end 
end 
  
function encrypt() 
    generateEncryptionArray(); 
    iTextSize = string.len(caText); 
    iEncryptedTextSize = iTextSize*3; 
    caEncryptedText = ""; 
    aEncryptedText = {}; 
    for i=1, iTextSize, 1 do 
        value = string.byte(caText,i); 
        n=i*3; 
        if (value < 10) then 
            value = string.format("00%i",value); 
        elseif (value < 100) then 
            value = string.format("0%i",value); 
        else 
            value = string.format("%i",value); 
        end 
        aEncryptedText[(i-1)*3+1] = string.byte(value,1) - 48; 
        aEncryptedText[(i-1)*3+2] = string.byte(value,2) - 48; 
        aEncryptedText[(i-1)*3+3] = string.byte(value,3) - 48; 
    end 
    iCounter = 1; 
    iPasswordPosition = 1; 
    for runs=1, 32, 1 do 
        for i=1, iEncryptedTextSize, 1 do 
            iCounter = iCounter + 1; 
            pos1 = i; 
            pos2 = i+1; 
            pos3 = i+2; 
            if (pos2 > iEncryptedTextSize) then 
                pos2 = pos2 - iEncryptedTextSize; 
                pos3 = pos3 - iEncryptedTextSize; 
            elseif (pos3 > iEncryptedTextSize) then 
                pos3 = pos3 - iEncryptedTextSize; 
            end 
            h = aEncryptedText[pos1]; 
            z = aEncryptedText[pos2]; 
            e = aEncryptedText[pos3]; 
            value = 100*h + 10*z + e; 
            value = iaEncryptionArray[value]; 
            value = subsEncryptionPasswordChar(value); 
            h = math.floor(value / 100); 
            value = value - 100*h; 
            z = math.floor(value / 10); 
            value = value - 10*z; 
            e = value; 
            aEncryptedText[pos1] = h; 
            aEncryptedText[pos2] = z; 
            aEncryptedText[pos3] = e; 
        end 
    end 
    caEncryptedText = ""; 
    for i=1,iEncryptedTextSize,1 do 
        caEncryptedText = caEncryptedText .. string.format("%i",aEncryptedText[i]); 
    end 
end 
  
function decrypt() 
    generateDecryptionArray(); 
    iEncryptedTextSize = string.len(caEncryptedText); 
    aEncryptedText = {}; 
    for i=1,iEncryptedTextSize,1 do 
        aEncryptedText[i] = string.byte(caEncryptedText,i) - 48; 
    end 
    caEncryptedText = ""; 
    iPasswordPosition = - (iEncryptedTextSize*32) - 1; 
    iPasswordPosition = iPasswordPosition % iPasswordLength + 1; 
    for runs=1, 32, 1 do 
        for i=iEncryptedTextSize, 1, -1 do 
            pos1 = i; 
            pos2 = i+1; 
            pos3 = i+2; 
            if (pos2 > iEncryptedTextSize) then 
                pos2 = pos2 - iEncryptedTextSize; 
                pos3 = pos3 - iEncryptedTextSize; 
            elseif (pos3 > iEncryptedTextSize) then 
                pos3 = pos3 - iEncryptedTextSize; 
            end 
            h = aEncryptedText[pos1]; 
            z = aEncryptedText[pos2]; 
            e = aEncryptedText[pos3]; 
            value = 100*h + 10*z + e; 
            value = addEncryptionPasswordChar(value); 
            value = iaDecryptionArray[value]; 
            h = math.floor(value / 100); 
            value = value - 100*h; 
            z = math.floor(value / 10); 
            value = value - 10*z; 
            e = value; 
            aEncryptedText[pos1] = h; 
            aEncryptedText[pos2] = z; 
            aEncryptedText[pos3] = e; 
        end 
    end 
    iTextSize = iEncryptedTextSize / 3 
    caText = ""; 
    for i=1,iEncryptedTextSize,1 do 
        caEncryptedText = caEncryptedText .. string.format("%i",aEncryptedText[i]); 
    end 
    for i=1, iTextSize, 1 do 
        n = (i-1)*3+1; 
        char = aEncryptedText[n]*100 + aEncryptedText[n+1]*10 + aEncryptedText[n+2]; 
        if char > 255 then 
            caText = "wrong password!"; 
            return; 
        end 
        caText = caText .. string.char(char); 
    end 
end 
  
function encryptString(caTextInput,caPasswordInput) 
    if caTextInput == nil or caPasswordInput == nil then 
        return nil; 
    end 
    caText = caTextInput; 
    caPassword = caPasswordInput; 
    iPasswordLength = string.len(caPassword); 
    encrypt(); 
    return (caEncryptedText); 
end 
  
function decryptString(caTextInput,caPasswordInput) 
    if caTextInput == nil or caPasswordInput == nil then 
        return nil; 
    end 
    caEncryptedText = caTextInput; 
    caPassword = caPasswordInput; 
    iPasswordLength = string.len(caPassword); 
    decrypt(); 
    return (caText); 
end 
  

The string:

A simple LUA encryption

Was encrypted to:

682119734823703509077954997710015337233693472802500191840149774364729

The string:

1234567890

Was encrypted to:

933712879701133814501918158559

The string:

abcdefghijklmnopqrstuvwxyz

Was encrypted to:

530526185999974651768906379994835597147588329912489932067818658885112960517611

The string:

TEST

Was encrypted to:

627098568592

The string:

one

Was encrypted to:

454931977