One-time pad: Difference between revisions

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<pre>
<pre>
Similar (not exactly the same, of course) as the Kotlin sample session.
Similar (not exactly the same, of course) as the Kotlin sample session.
</pre>

=={{header|Java}}==
Implementation supports multiple pads using the control name. <br>

Implementation also includes the start and end ASCII characters. One usage shows support for uppercase only, a second usage shows allowing spaces, upper case, and lower case in the input text.

<lang java>
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Random;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class OneTimePad {

public static void main(String[] args) {
String controlName = "AtomicBlonde";
generatePad(controlName, 5, 60, 65, 90);
String text = "IT WAS THE BEST OF TIMES IT WAS THE WORST OF TIMES";
String encrypted = parse(true, controlName, text.replaceAll(" ", ""));
String decrypted = parse(false, controlName, encrypted);
System.out.println("Input text = " + text);
System.out.println("Encrypted text = " + encrypted);
System.out.println("Decrypted text = " + decrypted);

controlName = "AtomicBlondeCaseSensitive";
generatePad(controlName, 5, 60, 32, 126);
text = "It was the best of times, it was the worst of times.";
encrypted = parse(true, controlName, text);
decrypted = parse(false, controlName, encrypted);
System.out.println();
System.out.println("Input text = " + text);
System.out.println("Encrypted text = " + encrypted);
System.out.println("Decrypted text = " + decrypted);
}
private static String parse(boolean encryptText, String controlName, String text) {
StringBuilder sb = new StringBuilder();
int minCh = 0;
int maxCh = 0;
Pattern minChPattern = Pattern.compile("^# MIN_CH = ([\\d]+)$");
Pattern maxChPattern = Pattern.compile("^# MAX_CH = ([\\d]+)$");
boolean validated = false;
try (BufferedReader in = new BufferedReader(new FileReader(getFileName(controlName))); ) {
String inLine = null;
while ( (inLine = in.readLine()) != null ) {
Matcher minMatcher = minChPattern.matcher(inLine);
if ( minMatcher.matches() ) {
minCh = Integer.parseInt(minMatcher.group(1));
continue;
}
Matcher maxMatcher = maxChPattern.matcher(inLine);
if ( maxMatcher.matches() ) {
maxCh = Integer.parseInt(maxMatcher.group(1));
continue;
}
if ( ! validated && minCh > 0 && maxCh > 0 ) {
validateText(text, minCh, maxCh);
validated = true;
}
// # is comment. - is used key.
if ( inLine.startsWith("#") || inLine.startsWith("-") ) {
continue;
}
// Have encryption key.
String key = inLine;
if ( encryptText ) {
for ( int i = 0 ; i < text.length(); i++) {
sb.append((char) (((text.charAt(i) - minCh + key.charAt(i) - minCh) % (maxCh - minCh + 1)) + minCh));
}
}
else {
for ( int i = 0 ; i < text.length(); i++) {
int decrypt = text.charAt(i) - key.charAt(i);
if ( decrypt < 0 ) {
decrypt += maxCh - minCh + 1;
}
decrypt += minCh;
sb.append((char) decrypt);
}
}
break;
}
} catch (IOException e) {
throw new RuntimeException(e);
}
return sb.toString();
}

private static void validateText(String text, int minCh, int maxCh) {
// Validate text is in range
for ( char ch : text.toCharArray() ) {
if ( ch != ' ' && (ch < minCh || ch > maxCh) ) {
throw new IllegalArgumentException("ERROR 103: Invalid text.");
}
}
}
private static String getFileName(String controlName) {
return controlName + ".1tp";
}
private static void generatePad(String controlName, int keys, int keyLength, int minCh, int maxCh) {
Random random = new Random();
try ( BufferedWriter writer = new BufferedWriter(new FileWriter(getFileName(controlName), false)); ) {
writer.write("# Lines starting with '#' are ignored.");
writer.newLine();
writer.write("# Lines starting with '-' are previously used.");
writer.newLine();
writer.write("# MIN_CH = " + minCh);
writer.newLine();
writer.write("# MAX_CH = " + maxCh);
writer.newLine();
for ( int line = 0 ; line < keys ; line++ ) {
StringBuilder sb = new StringBuilder();
for ( int ch = 0 ; ch < keyLength ; ch++ ) {
sb.append((char) (random.nextInt(maxCh - minCh + 1) + minCh));
}
writer.write(sb.toString());
writer.newLine();
}
writer.write("# EOF");
writer.newLine();
} catch (Exception e) {
throw new RuntimeException(e);
}
}

}
</lang>

{{out}}
Demonstration of job:
<pre>
Input text = IT WAS THE BEST OF TIMES IT WAS THE WORST OF TIMES
Encrypted text = ANFNPULTOZRSUNBACQXBMUVIGNWSRJFFNCBVCNF
Decrypted text = ITWASTHEBESTOFTIMESITWASTHEWORSTOFTIMES

Input text = It was the best of times, it was the worst of times.
Encrypted text = jF,2abB`:3f9}@85"Y.k[JyWRNO\(q~0Z-5_P:E_H3Q0U(2>'eWy
Decrypted text = It was the best of times, it was the worst of times.
</pre>
Generated one time pad supporting uppercase only.
<pre>
# Lines starting with '#' are ignored.
# Lines starting with '-' are previously used.
# MIN_CH = 65
# MAX_CH = 90
SUJNXBEPNVZZGIISQMFTTYVQNGSWDSNMZXINQJNEQHFBLCSZFCHJGKDLPQPN
RQMZKUCZQZXQDTKXKSVRCFNZYTGZWCDPPMCHDHORVFWBLXJLWTJRBRGUOYWM
PKEVUUBDOMBSFXVJFWGORCZPBSQOWZEOFFHZARVJWTEUQUAKGTMHFAVZSVOO
DKNEKKCTQITFVSOWKMXAOQKWTUYOUXICSEWYCPGOPWFKHYZXQXOIVQUZWWZB
NQUICNAJLTKDFSPXVBIVUUYUTZNNRNBQQXAGPERXZQNQLHEUXSRNIADKXZCL
# EOF
</pre>

Generated one time pad supporting lowercase, uppercase, symbols, and spaces.
<pre>
# Lines starting with '#' are ignored.
# Lines starting with '-' are previously used.
# MIN_CH = 32
# MAX_CH = 126
AQ,: nBkQMfV8LC52r.vq\4cFNeg(y=<Z8LyPBUlT>Q@n(=T9 ckJJt6c59[
A{qjk{}x?vlu5(/I4IrkC0NJS2}?_a xF__;5V& -Nz7qh@7OD}l<u9~xGMZ
6JOW|8cZ<,O:vp*LMwU~5u@AJ5nVG7 x?_zfyY(>QMA|U37Z39B}M-lnI-GB
|Qe1*V^PHo"\M:YQo1Z$}2XUk[,L(<P+RDso>'LE.>#K)I6IvrJ&l}O<~=C^
rx0ubl%t(-tOnCQz_y5k%xlHHi$cvaRCIYD<5nUFWD5Hmd@K2.{/N^>PP.<I
# EOF
</pre>
</pre>


Revision as of 22:37, 11 February 2020

One-time pad is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

Implement a One-time pad, for encrypting and decrypting messages.
To keep it simple, we will be using letters only.

Sub-Tasks
  • Generate the data for a One-time pad (user needs to specify a filename and length)
The important part is to get "true random" numbers, e.g. from /dev/random
  • encryption / decryption ( basically the same operation, much like Rot-13 )
For this step, much of Vigenère cipher could be reused,
with the key to be read from the file containing the One-time pad.
  • optional: management of One-time pads: list, mark as used, delete, etc.
Somehow, the users needs to keep track which pad to use for which partner.

To support the management of pad-files:

  • Such files have a file-extension ".1tp"
  • Lines starting with "#" may contain arbitary meta-data (i.e. comments)
  • Lines starting with "-" count as "used"
  • Whitespace within the otp-data is ignored


For example, here is the data from Wikipedia: 

# Example data - Wikipedia - 2014-11-13
-ZDXWWW EJKAWO FECIFE WSNZIP PXPKIY URMZHI JZTLBC YLGDYJ 
-HTSVTV RRYYEG EXNCGA GGQVRF FHZCIB EWLGGR BZXQDQ DGGIAK 
 YHJYEQ TDLCQT HZBSIZ IRZDYS RBYJFZ AIRCWI UCVXTW YKPQMK 
 CKHVEX VXYVCS WOGAAZ OUVVON GCNEVR LMBLYB SBDCDC PCGVJX 
 QXAUIP PXZQIJ JIUWYH COVWMJ UZOJHL DWHPER UBSRUJ HGAAPR 
 CRWVHI FRNTQW AJVWRT ACAKRD OZKIIB VIQGBK IJCWHF GTTSSE 
 EXFIPJ KICASQ IOUQTP ZSGXGH YTYCTI BAZSTN JKMFXI RERYWE



See also



Go

Translation of: Kotlin

<lang go>package main

import ( 

   "bufio"
   "crypto/rand"
   "fmt"
   "io/ioutil"
   "log"
   "math/big"
   "os"
   "strconv"
   "strings"
   "unicode"

)

const ( 

   charsPerLine = 48
   chunkSize    = 6
   cols         = 8
   demo         = true // would normally be set to false

)

type fileType int

const ( 

   otp fileType = iota
   enc
   dec

)

var scnr = bufio.NewScanner(os.Stdin)

func check(err error) { 

   if err != nil {
       log.Fatal(err)
   }

}

func toAlpha(s string) string { 

   var filtered []rune
   for _, r := range s {
       if unicode.IsUpper(r) {
           filtered = append(filtered, r)
       }
   }
   return string(filtered)

}

func isOtpRelated(s string) bool { 

   return strings.HasSuffix(s, ".1tp") || strings.HasSuffix(s, "1tp_cpy") ||
       strings.HasSuffix(s, ".1tp_enc") || strings.HasSuffix(s, "1tp_dec")

}

func makePad(nLines int) string { 

   nChars := nLines * charsPerLine
   bytes := make([]byte, nChars)
   /* generate random upper case letters */
   max := big.NewInt(26)
   for i := 0; i < nChars; i++ {
       n, err := rand.Int(rand.Reader, max)
       check(err)
       bytes[i] = byte(65 + n.Uint64())
   }
   return inChunks(string(bytes), nLines, otp)

}

func vigenere(text, key string, encrypt bool) string { 

   bytes := make([]byte, len(text))
   var ci byte
   for i, c := range text {
       if encrypt {
           ci = (byte(c) + key[i] - 130) % 26
       } else {
           ci = (byte(c) + 26 - key[i]) % 26
       }
       bytes[i] = ci + 65
   }
   temp := len(bytes) % charsPerLine
   if temp > 0 { // pad with random characters so each line is a full one
       max := big.NewInt(26)
       for i := temp; i < charsPerLine; i++ {
           n, err := rand.Int(rand.Reader, max)
           check(err)
           bytes = append(bytes, byte(65+n.Uint64()))
       }
   }
   ft := enc
   if !encrypt {
       ft = dec
   }
   return inChunks(string(bytes), len(bytes)/charsPerLine, ft)

}

func inChunks(s string, nLines int, ft fileType) string { 

   nChunks := len(s) / chunkSize
   remainder := len(s) % chunkSize
   chunks := make([]string, nChunks)
   for i := 0; i < nChunks; i++ {
       chunks[i] = s[i*chunkSize : (i+1)*chunkSize]
   }
   if remainder > 0 {
       chunks = append(chunks, s[nChunks*chunkSize:])
   }
   var sb strings.Builder
   for i := 0; i < nLines; i++ {
       j := i * cols
       sb.WriteString(" " + strings.Join(chunks[j:j+cols], " ") + "\n")
   }
   ss := " file\n" + sb.String()
   switch ft {
   case otp:
       return "# OTP" + ss
   case enc:
       return "# Encrypted" + ss
   default: // case dec:
       return "# Decrypted" + ss
   }

}

func menu() int { 

   fmt.Println(`

1. Create one time pad file.

2. Delete one time pad file.

3. List one time pad files.

4. Encrypt plain text.

5. Decrypt cipher text.

6. Quit program. `) 

   choice := 0
   for choice < 1 || choice > 6 {
       fmt.Print("Your choice (1 to 6) : ")
       scnr.Scan()
       choice, _ = strconv.Atoi(scnr.Text())
       check(scnr.Err())
   }
   return choice

}

func main() { 

   for {
       choice := menu()
       fmt.Println()
       switch choice {
       case 1: // Create OTP
           fmt.Println("Note that encrypted lines always contain 48 characters.\n")
           fmt.Print("OTP file name to create (without extension) : ")
           scnr.Scan()
           fileName := scnr.Text() + ".1tp"
           nLines := 0
           for nLines < 1 || nLines > 1000 {
               fmt.Print("Number of lines in OTP (max 1000) : ")
               scnr.Scan()
               nLines, _ = strconv.Atoi(scnr.Text())
           }
           check(scnr.Err())
           key := makePad(nLines)
           file, err := os.Create(fileName)
           check(err)
           _, err = file.WriteString(key)
           check(err)
           file.Close()
           fmt.Printf("\n'%s' has been created in the current directory.\n", fileName)
           if demo {
               // a copy of the OTP file would normally be on a different machine
               fileName2 := fileName + "_cpy" // copy for decryption
               file, err := os.Create(fileName2)
               check(err)
               _, err = file.WriteString(key)
               check(err)
               file.Close()
               fmt.Printf("'%s' has been created in the current directory.\n", fileName2)
               fmt.Println("\nThe contents of these files are :\n")
               fmt.Println(key)
           }
       case 2: // Delete OTP
           fmt.Println("Note that this will also delete ALL associated files.\n")
           fmt.Print("OTP file name to delete (without extension) : ")
           scnr.Scan()
           toDelete1 := scnr.Text() + ".1tp"
           check(scnr.Err())
           toDelete2 := toDelete1 + "_cpy"
           toDelete3 := toDelete1 + "_enc"
           toDelete4 := toDelete1 + "_dec"
           allToDelete := []string{toDelete1, toDelete2, toDelete3, toDelete4}
           deleted := 0
           fmt.Println()
           for _, name := range allToDelete {
               if _, err := os.Stat(name); !os.IsNotExist(err) {
                   err = os.Remove(name)
                   check(err)
                   deleted++
                   fmt.Printf("'%s' has been deleted from the current directory.\n", name)
               }
           }
           if deleted == 0 {
               fmt.Println("There are no files to delete.")
           }
       case 3: // List OTPs
           fmt.Println("The OTP (and related) files in the current directory are:\n")
           files, err := ioutil.ReadDir(".") // already sorted by file name
           check(err)
           for _, fi := range files {
               name := fi.Name()
               if !fi.IsDir() && isOtpRelated(name) {
                   fmt.Println(name)
               }
           }
       case 4: // Encrypt
           fmt.Print("OTP file name to use (without extension) : ")
           scnr.Scan()
           keyFile := scnr.Text() + ".1tp"
           if _, err := os.Stat(keyFile); !os.IsNotExist(err) {
               file, err := os.Open(keyFile)
               check(err)
               bytes, err := ioutil.ReadAll(file)
               check(err)
               file.Close()
               lines := strings.Split(string(bytes), "\n")
               le := len(lines)
               first := le
               for i := 0; i < le; i++ {
                   if strings.HasPrefix(lines[i], " ") {
                       first = i
                       break
                   }
               }
               if first == le {
                   fmt.Println("\nThat file has no unused lines.")
                   continue
               }
               lines2 := lines[first:] // get rid of comments and used lines

               fmt.Println("Text to encrypt :-\n")
               scnr.Scan()
               text := toAlpha(strings.ToUpper(scnr.Text()))
               check(scnr.Err())
               tl := len(text)
               nLines := tl / charsPerLine
               if tl%charsPerLine > 0 {
                   nLines++
               }
               if len(lines2) >= nLines {
                   key := toAlpha(strings.Join(lines2[0:nLines], ""))
                   encrypted := vigenere(text, key, true)
                   encFile := keyFile + "_enc"
                   file2, err := os.Create(encFile)
                   check(err)
                   _, err = file2.WriteString(encrypted)
                   check(err)
                   file2.Close()
                   fmt.Printf("\n'%s' has been created in the current directory.\n", encFile)
                   for i := first; i < first+nLines; i++ {
                       lines[i] = "-" + lines[i][1:]
                   }
                   file3, err := os.Create(keyFile)
                   check(err)
                   _, err = file3.WriteString(strings.Join(lines, "\n"))
                   check(err)
                   file3.Close()
                   if demo {
                       fmt.Println("\nThe contents of the encrypted file are :\n")
                       fmt.Println(encrypted)
                   }
               } else {
                   fmt.Println("Not enough lines left in that file to do encryption.")
               }
           } else {
               fmt.Println("\nThat file does not exist.")
           }
       case 5: // Decrypt
           fmt.Print("OTP file name to use (without extension) : ")
           scnr.Scan()
           keyFile := scnr.Text() + ".1tp_cpy"
           check(scnr.Err())
           if _, err := os.Stat(keyFile); !os.IsNotExist(err) {
               file, err := os.Open(keyFile)
               check(err)
               bytes, err := ioutil.ReadAll(file)
               check(err)
               file.Close()
               keyLines := strings.Split(string(bytes), "\n")
               le := len(keyLines)
               first := le
               for i := 0; i < le; i++ {
                   if strings.HasPrefix(keyLines[i], " ") {
                       first = i
                       break
                   }
               }
               if first == le {
                   fmt.Println("\nThat file has no unused lines.")
                   continue
               }
               keyLines2 := keyLines[first:] // get rid of comments and used lines

               encFile := keyFile[0:len(keyFile)-3] + "enc"
               if _, err := os.Stat(encFile); !os.IsNotExist(err) {
                   file2, err := os.Open(encFile)
                   check(err)
                   bytes, err := ioutil.ReadAll(file2)
                   check(err)
                   file2.Close()
                   encLines := strings.Split(string(bytes), "\n")[1:] // exclude comment line
                   nLines := len(encLines)
                   if len(keyLines2) >= nLines {
                       encrypted := toAlpha(strings.Join(encLines, ""))
                       key := toAlpha(strings.Join(keyLines2[0:nLines], ""))
                       decrypted := vigenere(encrypted, key, false)
                       decFile := keyFile[0:len(keyFile)-3] + "dec"
                       file3, err := os.Create(decFile)
                       check(err)
                       _, err = file3.WriteString(decrypted)
                       check(err)
                       file3.Close()
                       fmt.Printf("\n'%s' has been created in the current directory.\n", decFile)
                       for i := first; i < first+nLines; i++ {
                           keyLines[i] = "-" + keyLines[i][1:]
                       }
                       file4, err := os.Create(keyFile)
                       check(err)
                       _, err = file4.WriteString(strings.Join(keyLines, "\n"))
                       check(err)
                       file4.Close()
                       if demo {
                           fmt.Println("\nThe contents of the decrypted file are :\n")
                           fmt.Println(decrypted)
                       }
                   }
               } else {
                   fmt.Println("Not enough lines left in that file to do decryption.")
               }
           } else {
               fmt.Println("\nThat file does not exist.")
           }
       case 6: // Quit program
           return
       }
   }

}</lang>

Output:
Similar (not exactly the same, of course) as the Kotlin sample session.

Java

Implementation supports multiple pads using the control name.

Implementation also includes the start and end ASCII characters. One usage shows support for uppercase only, a second usage shows allowing spaces, upper case, and lower case in the input text.

<lang java> import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Random; import java.util.regex.Matcher; import java.util.regex.Pattern;

public class OneTimePad { 

   public static void main(String[] args) {
       String controlName = "AtomicBlonde";
       generatePad(controlName, 5, 60, 65, 90);
       String text = "IT WAS THE BEST OF TIMES IT WAS THE WORST OF TIMES";
       String encrypted = parse(true, controlName, text.replaceAll(" ", ""));
       String decrypted = parse(false, controlName, encrypted);
       System.out.println("Input  text    = " + text);
       System.out.println("Encrypted text = " + encrypted);
       System.out.println("Decrypted text = " + decrypted);

       controlName = "AtomicBlondeCaseSensitive";
       generatePad(controlName, 5, 60, 32, 126);
       text = "It was the best of times, it was the worst of times.";
       encrypted = parse(true, controlName, text);
       decrypted = parse(false, controlName, encrypted);
       System.out.println();
       System.out.println("Input text     = " + text);
       System.out.println("Encrypted text = " + encrypted);
       System.out.println("Decrypted text = " + decrypted);
   }
   
   private static String parse(boolean encryptText, String controlName, String text) {
       StringBuilder sb = new StringBuilder();
       int minCh = 0;
       int maxCh = 0;
       Pattern minChPattern = Pattern.compile("^#  MIN_CH = ([\\d]+)$");
       Pattern maxChPattern = Pattern.compile("^#  MAX_CH = ([\\d]+)$");
       boolean validated = false;
       try (BufferedReader in = new BufferedReader(new FileReader(getFileName(controlName))); ) {
           String inLine = null;
           while ( (inLine = in.readLine()) != null ) {
               Matcher minMatcher = minChPattern.matcher(inLine);
               if ( minMatcher.matches() ) {
                   minCh = Integer.parseInt(minMatcher.group(1));
                   continue;
               }
               Matcher maxMatcher = maxChPattern.matcher(inLine);
               if ( maxMatcher.matches() ) {
                   maxCh = Integer.parseInt(maxMatcher.group(1));
                   continue;
               }
               if ( ! validated && minCh > 0 && maxCh > 0 ) {
                   validateText(text, minCh, maxCh);
                   validated = true;
               }
               //  # is comment.  - is used key. 
               if ( inLine.startsWith("#") || inLine.startsWith("-") ) {
                   continue;
               }
               //  Have encryption key.
               String key = inLine;
               if ( encryptText ) {
                   for ( int i = 0 ; i < text.length(); i++) {
                       sb.append((char) (((text.charAt(i) - minCh + key.charAt(i) - minCh) % (maxCh - minCh + 1)) + minCh));
                   }
               }
               else {
                   for ( int i = 0 ; i < text.length(); i++) {
                       int decrypt = text.charAt(i) - key.charAt(i);
                       if ( decrypt < 0 ) {
                           decrypt += maxCh - minCh + 1;
                       }
                       decrypt += minCh;
                       sb.append((char) decrypt);
                   }
               }
               break;
           }
       } catch (IOException e) {
           throw new RuntimeException(e);
       }
       return sb.toString();
   }

   private static void validateText(String text, int minCh, int maxCh) {
       //  Validate text is in range
       for ( char ch : text.toCharArray() ) {
           if ( ch != ' ' && (ch < minCh || ch > maxCh) ) {
               throw new IllegalArgumentException("ERROR 103:  Invalid text.");
           }
       }
       
   }
   
   private static String getFileName(String controlName) {
       return controlName + ".1tp";
   }
   
   private static void generatePad(String controlName, int keys, int keyLength, int minCh, int maxCh) {
       Random random = new Random();
       try ( BufferedWriter writer = new BufferedWriter(new FileWriter(getFileName(controlName), false)); ) {
           writer.write("#  Lines starting with '#' are ignored.");
           writer.newLine();
           writer.write("#  Lines starting with '-' are previously used.");
           writer.newLine();
           writer.write("#  MIN_CH = " + minCh);
           writer.newLine();
           writer.write("#  MAX_CH = " + maxCh);
           writer.newLine();
           for ( int line = 0 ; line < keys ; line++ ) {
               StringBuilder sb = new StringBuilder();
               for ( int ch = 0 ; ch < keyLength ; ch++ ) {
                   sb.append((char) (random.nextInt(maxCh - minCh + 1) + minCh));
               }
               writer.write(sb.toString());
               writer.newLine();
           }
           writer.write("#  EOF");
           writer.newLine();
       } catch (Exception e) {
           throw new RuntimeException(e);
       }
   }

} </lang>

Output:

Demonstration of job: 

Input  text    = IT WAS THE BEST OF TIMES IT WAS THE WORST OF TIMES
Encrypted text = ANFNPULTOZRSUNBACQXBMUVIGNWSRJFFNCBVCNF
Decrypted text = ITWASTHEBESTOFTIMESITWASTHEWORSTOFTIMES

Input text     = It was the best of times, it was the worst of times.
Encrypted text = jF,2abB`:3f9}@85"Y.k[JyWRNO\(q~0Z-5_P:E_H3Q0U(2>'eWy
Decrypted text = It was the best of times, it was the worst of times.

Generated one time pad supporting uppercase only. 

#  Lines starting with '#' are ignored.
#  Lines starting with '-' are previously used.
#  MIN_CH = 65
#  MAX_CH = 90
SUJNXBEPNVZZGIISQMFTTYVQNGSWDSNMZXINQJNEQHFBLCSZFCHJGKDLPQPN
RQMZKUCZQZXQDTKXKSVRCFNZYTGZWCDPPMCHDHORVFWBLXJLWTJRBRGUOYWM
PKEVUUBDOMBSFXVJFWGORCZPBSQOWZEOFFHZARVJWTEUQUAKGTMHFAVZSVOO
DKNEKKCTQITFVSOWKMXAOQKWTUYOUXICSEWYCPGOPWFKHYZXQXOIVQUZWWZB
NQUICNAJLTKDFSPXVBIVUUYUTZNNRNBQQXAGPERXZQNQLHEUXSRNIADKXZCL
#  EOF

Generated one time pad supporting lowercase, uppercase, symbols, and spaces. 

#  Lines starting with '#' are ignored.
#  Lines starting with '-' are previously used.
#  MIN_CH = 32
#  MAX_CH = 126
AQ,: nBkQMfV8LC52r.vq\4cFNeg(y=<Z8LyPBUlT>Q@n(=T9 ckJJt6c59[
A{qjk{}x?vlu5(/I4IrkC0NJS2}?_a xF__;5V& -Nz7qh@7OD}l<u9~xGMZ
6JOW|8cZ<,O:vp*LMwU~5u@AJ5nVG7 x?_zfyY(>QMA|U37Z39B}M-lnI-GB
|Qe1*V^PHo"\M:YQo1Z$}2XUk[,L(<P+RDso>'LE.>#K)I6IvrJ&l}O<~=C^
rx0ubl%t(-tOnCQz_y5k%xlHHi$cvaRCIYD<5nUFWD5Hmd@K2.{/N^>PP.<I
#  EOF

Julia

See One-time pad/Julia

Kotlin

This uses the JDK's SecureRandom class for generating cryptographically strong random numbers. For convenience all three sub-tasks are catered for by a single, menu-based, program. <lang scala>// version 1.2.31

import java.io.File import java.security.SecureRandom

const val CHARS_PER_LINE = 48 const val CHUNK_SIZE = 6 const val COLS = 8 const val DEMO = true // would normally be set to false

enum class FileType { OTP, ENC, DEC }

fun Char.isAlpha() = this in 'A'..'Z'

fun String.toAlpha() = this.filter { it.isAlpha() }

fun String.isOtpRelated() = endsWith(".1tp") || endsWith(".1tp_cpy") || 

                           endsWith(".1tp_enc") || endsWith(".1tp_dec")

fun makePad(nLines: Int): String { 

   val nChars = nLines * CHARS_PER_LINE
   val sr = SecureRandom()
   val sb = StringBuilder(nChars)
   /* generate random upper case letters */
   for (i in 0 until nChars) sb.append((sr.nextInt(26) + 65).toChar())
   return sb.toString().inChunks(nLines, FileType.OTP)

}

fun vigenere(text: String, key: String, encrypt: Boolean = true): String { 

   val sb = StringBuilder(text.length)
   for ((i, c) in text.withIndex()) {
       val ci = if (encrypt)
           (c.toInt() + key[i].toInt() - 130) % 26
       else
           (c.toInt() - key[i].toInt() +  26) % 26
       sb.append((ci + 65).toChar())
   }
   val temp = sb.length % CHARS_PER_LINE
   if (temp > 0) {  // pad with random characters so each line is a full one
       val sr = SecureRandom()
       for (i in temp until CHARS_PER_LINE) sb.append((sr.nextInt(26) + 65).toChar())
   }
   val ft = if (encrypt) FileType.ENC else FileType.DEC
   return sb.toString().inChunks(sb.length / CHARS_PER_LINE, ft)

}

fun String.inChunks(nLines: Int, ft: FileType): String { 

   val chunks = this.chunked(CHUNK_SIZE)
   val sb = StringBuilder(this.length + nLines * (COLS + 1))
   for (i in 0 until nLines) {
       val j = i * COLS
       sb.append(" ${chunks.subList(j, j + COLS).joinToString(" ")}\n")
   }
   val s = " file\n" + sb.toString()
   return when (ft) {
       FileType.OTP -> "# OTP" + s
       FileType.ENC -> "# Encrypted" + s
       FileType.DEC -> "# Decrypted" + s
   }

}

fun menu(): Int { 

   println("""
       |
       |1. Create one time pad file.
       |
       |2. Delete one time pad file.
       |
       |3. List one time pad files.
       |
       |4. Encrypt plain text.
       |
       |5. Decrypt cipher text.
       |
       |6. Quit program.
       |
       """.trimMargin())
   var choice: Int?
   do {
       print("Your choice (1 to 6) : ")
       choice = readLine()!!.toIntOrNull()
   }
   while (choice == null || choice !in 1..6)
   return choice

}

fun main(args: Array<String>) { 

   mainLoop@ while (true) {
       val choice = menu()
       println()
       when (choice) {
           1 -> {  // Create OTP
               println("Note that encrypted lines always contain 48 characters.\n")
               print("OTP file name to create (without extension) : ")
               val fileName = readLine()!! + ".1tp"  
               var nLines: Int?

               do {
                   print("Number of lines in OTP (max 1000) : ")
                   nLines = readLine()!!.toIntOrNull()
               }
               while (nLines == null || nLines !in 1..1000)

               val key = makePad(nLines)
               File(fileName).writeText(key)
               println("\n'$fileName' has been created in the current directory.")
               if (DEMO) {
                   // a copy of the OTP file would normally be on a different machine
                   val fileName2 = fileName + "_cpy"  // copy for decryption
                   File(fileName2).writeText(key)
                   println("'$fileName2' has been created in the current directory.")
                   println("\nThe contents of these files are :\n")
                   println(key)
               }
           }

           2 -> {  // Delete OTP
               println("Note that this will also delete ALL associated files.\n")
               print("OTP file name to delete (without extension) : ")
               val toDelete1 = readLine()!! + ".1tp"
               val toDelete2 = toDelete1 + "_cpy"
               val toDelete3 = toDelete1 + "_enc"
               val toDelete4 = toDelete1 + "_dec"
               val allToDelete = listOf(toDelete1, toDelete2, toDelete3, toDelete4)
               var deleted = 0
               println()
               for (name in allToDelete) {
                   val f = File(name)
                   if (f.exists()) {
                       f.delete()
                       deleted++
                       println("'$name' has been deleted from the current directory.")
                   }
               }
               if (deleted == 0) println("There are no files to delete.")
           }

           3 -> {  // List OTPs
               println("The OTP (and related) files in the current directory are:\n")
               val otpFiles = File(".").listFiles().filter {
                   it.isFile() && it.name.isOtpRelated()
               }.map { it.name }.toMutableList()
               otpFiles.sort()
               println(otpFiles.joinToString("\n"))
           }

           4 -> {  // Encrypt
               print("OTP file name to use (without extension) : ")
               val keyFile = readLine()!! + ".1tp"
               val kf = File(keyFile)
               if (kf.exists()) {
                   val lines = File(keyFile).readLines().toMutableList()
                   var first = lines.size
                   for (i in 0 until lines.size) {
                       if (lines[i].startsWith(" ")) {
                           first = i
                           break
                       }
                   }
                   if (first == lines.size) {
                       println("\nThat file has no unused lines.")
                       continue@mainLoop
                   }
                   val lines2 = lines.drop(first)  // get rid of comments and used lines

                   println("Text to encrypt :-\n")
                   val text = readLine()!!.toUpperCase().toAlpha()
                   val len = text.length
                   var nLines = len / CHARS_PER_LINE
                   if (len % CHARS_PER_LINE > 0) nLines++

                   if (lines2.size >= nLines) {
                       val key = lines2.take(nLines).joinToString("").toAlpha()
                       val encrypted = vigenere(text, key)
                       val encFile = keyFile + "_enc"
                       File(encFile).writeText(encrypted)
                       println("\n'$encFile' has been created in the current directory.")
                       for (i in first until first + nLines) {
                           lines[i] = "-" + lines[i].drop(1)
                       }
                       File(keyFile).writeText(lines.joinToString("\n"))
                       if (DEMO) {
                           println("\nThe contents of the encrypted file are :\n")
                           println(encrypted)
                       }
                   }
                   else println("Not enough lines left in that file to do encryption")
               }
               else println("\nThat file does not exist.")
           }

           5 -> {  // Decrypt
               print("OTP file name to use (without extension) : ")
               val keyFile = readLine()!! + ".1tp_cpy"
               val kf = File(keyFile)
               if (kf.exists()) {
                   val keyLines = File(keyFile).readLines().toMutableList()
                   var first = keyLines.size
                   for (i in 0 until keyLines.size) {
                       if (keyLines[i].startsWith(" ")) {
                           first = i
                           break
                       }
                   }
                   if (first == keyLines.size) {
                       println("\nThat file has no unused lines.")
                       continue@mainLoop
                   }
                   val keyLines2 = keyLines.drop(first)  // get rid of comments and used lines

                   val encFile = keyFile.dropLast(3) + "enc"
                   val ef = File(encFile)
                   if (ef.exists()) {
                       val encLines = File(encFile).readLines().drop(1)  // exclude comment line
                       val nLines = encLines.size
                       if (keyLines2.size >= nLines) {
                           val encrypted = encLines.joinToString("").toAlpha()
                           val key = keyLines2.take(nLines).joinToString("").toAlpha()
                           val decrypted = vigenere(encrypted, key, false)
                           val decFile = keyFile.dropLast(3) + "dec"
                           File(decFile).writeText(decrypted)
                           println("\n'$decFile' has been created in the current directory.")
                           for (i in first until first + nLines) {
                               keyLines[i] = "-" + keyLines[i].drop(1)
                           }
                           File(keyFile).writeText(keyLines.joinToString("\n"))
                           if (DEMO) {
                               println("\nThe contents of the decrypted file are :\n")
                               println(decrypted)
                           }
                       }
                       else println("Not enough lines left in that file to do decryption")
                   }
                   else println("\n'$encFile' is missing.")
               }
               else println("\nThat file does not exist.")
           }

           else -> return  // Quit
       }
   }

}</lang>

Output:

Input/output for a sample session. In the interests of brevity, --<menu>-- indicates the re-display of the menu after the previous choice has been processed: 

1. Create one time pad file.

2. Delete one time pad file.

3. List one time pad files.

4. Encrypt plain text.

5. Decrypt cipher text.

6. Quit program.

Your choice (1 to 6) : 1

Note that encrypted lines always contain 48 characters.

OTP file name to create (without extension) : user1
Number of lines in OTP (max 1000) : 4

'user1.1tp' has been created in the current directory.
'user1.1tp_cpy' has been created in the current directory.

The contents of these files are :

# OTP file
 MZSAVH VHJLRS YLFXZB JWAHSN AHPCSE RUJMFX ZZPMFB QTTNLM
 LDANXY LGJEBV IRKDTR NHKOPG ZDUBDC KOOWZC HEBKWC YAHOFY
 DYPCXG TGCBXC VFETFM VOTHNI ZCGKNL QONXYE IDCROZ LHLWMN
 YWSGDO YYSNNV QMOJFM AHVOGP CDFAKM HZCWEX CEAXXV INKAEO


--<menu>--

Your choice (1 to 6) : 3

The OTP (and related) files in the current directory are:

user1.1tp
user1.1tp_cpy

--<menu>--

Your choice (1 to 6) : 4

OTP file name to use (without extension) : user1
Text to encrypt :-

Beware the Jabberwock, my son! The jaws that bite, the claws that catch!

'user1.1tp_enc' has been created in the current directory.

The contents of the encrypted file are :

# Encrypted file
 NDOAML OONURT ZPWTND TIYZGA TOTLSA JNQMYY HSTFMF SETJDF
 SDTPXR NNHVAO YSCVZU UTLAFM PEWGRH OJRCTF IOVEHK ZKETBQ


--<menu>--

Your choice (1 to 6) : 5

OTP file name to use (without extension) : user1

'user1.1tp_dec' has been created in the current directory.

The contents of the decrypted file are :

# Decrypted file
 BEWARE THEJAB BERWOC KMYSON THEJAW STHATB ITETHE CLAWST
 HATCAT CHYRZT QBSSGD HMBMQG QBCFOF EVDGUD BKUULI BKXFWS


--<menu>-

Your choice (1 to 6) : 2

Note that this will also delete ALL associated files.

OTP file name to delete (without extension) : user1

'user1.1tp' has been deleted from the current directory.
'user1.1tp_cpy' has been deleted from the current directory.
'user1.1tp_enc' has been deleted from the current directory.
'user1.1tp_dec' has been deleted from the current directory.

--<menu>--

Your choice (1 to 6) : 6

Perl 6

Works with: Rakudo version 2017.10

The task is somewhat under-specified, especially the third (optional) section so I'm skipping that for now. Each sub-task has it's own code.

Sub-task one: generate one-time-pad files.

This is a fairly basic otp file generator. Uses Crypt::Random for decently high quality random numbers. (Random bytes are drawn from /dev/urandom on Unix-like systems, and CryptGenRandom() on Windows.) It will ask for a file name to save to, and the number of lines you want. Each line can be used to encode up to 48 characters of data. Default is 1000 lines, Only generating 4 lines here for demonstration purposes. Saving the file to 'rosettacode.1tp'.

<lang perl6>sub MAIN { 

   put "Generate data for one time pad encryption.\n" ~
       "File will have .1tp extension.";
   my $fn;
   loop {
       $fn = prompt 'Filename for one time pad data: ';
       if $fn !~~ /'.1tp' $/ { $fn ~= '.1tp' }
       if $fn.IO.e {
           my $ow = prompt "$fn aready exists, over-write? y/[n] ";
           last if $ow ~~ m:i/'y'/;
           redo;
       }
       last;
   }

   put 'Each line will contain 48 characters of encyption data.';
   my $lines = prompt 'How many lines of data to generate? [1000] ';
   $lines ||= 1000;
   generate($fn, $lines);
   say "One-time-pad data saved to: ", $fn.IO.absolute;

   sub generate ( $fn, $lines) {
       use Crypt::Random;
       $fn.IO.spurt: "# one-time-pad encryption data\n" ~
         ((sprintf(" %s %s %s %s %s %s %s %s\n",
         ((('A'..'Z')[crypt_random_uniform(26)] xx 6).join) xx 8))
         xx $lines).join;
   }

}</lang>

Output:
Generate data for one time pad encryption.
File wile have .1tp extension.
Filename for one time pad data: rosettacode
Each line will contain 48 characters of encyption data.
How many lines of data to generate? [1000] 4
One-time-pad data saved to: /home/myhome/mydirectory/rosettacode.1tp

Sample file generated by above code: 

# one-time-pad encryption data
 DSUJOU UUWDZD VHFWRR AJDMDC ERZDGD WWKLHJ YITCML FORXCV
 BXGFCL ANGCGY VTAEUG UYAIPK FXWMNI INDLOR JIDZQL BOFFQD
 JISNOS CMLRPW TFGELQ HPTMRN SHBBDP AIVDAC CEWIFH TRLQVK
 FRBUUC GDCQHQ CEEURS RGVWVT JZIQLP NQCABF BWUPUI UDTZAF

Sub-task two: encrypt/decrypt text using the otp files generated by part one.

One-time-pad encryption gets it's security from the fact that the pads are used one time. As a line is used in the otp file, it needs to be marked as used, or removed so it doesn't get reused. Theoretically, you would make a copy of rosettacode.1tp and send it by secure means to the receiver of your encrypted text so that they can use it to decrypt. Since we are encrypting and decrypting on the same computer, we'll make a copy of the otp file named rosettacopy.1tp and use that for decryption so the encrypt and decrypt functions don't conflict.

<lang perl6>sub s2v ($s) { $s.uc.comb(/ <[ A..Z ]> /)».ord »-» 65 } sub v2s (@v) { (@v »%» 26 »+» 65)».chr.join }

sub hide ($secret, $otp) { v2s(s2v($secret) »+» s2v($otp)) } sub reveal ($hidden, $otp) { v2s(s2v($hidden) »-» s2v($otp)) }

sub otp-data ($fn, $lines) { 

   my $fh = $fn.IO.open :rw;
   my $data;
   my $count = 0;
   repeat {
       my $pos = $fh.tell;
       my $line = $fh.get;
       if $line.substr(0,1) ne '-'|'#' {
           $data ~= $line;
           $fh.seek($pos);
           $fh.put: '-' ~ $line.substr(1);
           $count++;
       }
   } until $count == $lines or $fh.eof;
   note "Insufficient lines of data remaining in $fn" if $count != $lines;
   $data;

}

sub otp-size (Str $string) { ceiling $string.uc.comb(/ <[ A..Z ]> /) / 48 }

sub otp-encrypt ( $secret, $fn ) { 

   my $otp-size = otp-size $secret;
   my $otp-data = otp-data($fn, $otp-size);
   my $encrypted = hide $secret, $otp-data;
   # pad encryted text out to a full line with random text
   $encrypted ~= ('A'..'Z').roll while $encrypted.chars % 48;
   join "\n", $encrypted.comb(6).rotor(8, :partial).map:
     { sprintf "{ join ' ', "%s" xx $_ }", $_ };

}

sub otp-decrypt ( $secret, $fn ) { 

   my $otp-size = otp-size $secret;
   my $otp-data = otp-data($fn, $otp-size);
   my $plain-text = reveal $secret, $otp-data;
   join "\n", $plain-text.comb(6).rotor(8, :partial).map:
     { sprintf "{ join ' ', "%s" xx $_ }", $_ };

}

my $otp-encrypt-fn = 'rosettacode.1tp'; my $otp-decrypt-fn = 'rosettacopy.1tp';

my $secret = "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!";

say "Secret:\n$secret\n\nEncrypted:"; say my $encrypted = otp-encrypt $secret, $otp-encrypt-fn; say "\nDecrypted:\n", otp-decrypt $encrypted, $otp-decrypt-fn;</lang>

Output:
Secret:
Beware the Jabberwock, my son! The jaws that bite, the claws that catch!

Encrypted:
EWQJFY NBAMZE WLWSFT KVBERP XYDMGZ OPRLAK GBXVTP HZRTUO
IXZHCE CUUORL THOFDI DCXRLG JQICPI ZEREHP RLOEAE PRMVJH

Decrypted:
BEWARE THEJAB BERWOC KMYSON THEJAW STHATB ITETHE CLAWST
HATCAT CHOMLN YOOBJC JEXJWW ETMQCA RROTTY IDLFKT ODHQTE

Contents of rosettacode.1tp after encryption / rosettacopy.1tp after decryption: 

# one-time-pad encryption data
-DSUJOU UUWDZD VHFWRR AJDMDC ERZDGD WWKLHJ YITCML FORXCV
-BXGFCL ANGCGY VTAEUG UYAIPK FXWMNI INDLOR JIDZQL BOFFQD
 JISNOS CMLRPW TFGELQ HPTMRN SHBBDP AIVDAC CEWIFH TRLQVK
 FRBUUC GDCQHQ CEEURS RGVWVT JZIQLP NQCABF BWUPUI UDTZAF

Phix

See One-time pad/Phix

Racket

See One-time pad/Racket

Tcl

Part 1: random strings

Get true random numbers, and turn them into strings.

With "randInt" from Tcl'ers wiki Cryptographically secure random numbers using /dev/urandom

<lang Tcl>puts "# True random chars for one-time pad"

proc randInt { min max } { 

   set randDev [open /dev/urandom rb]
   set random [read $randDev 8]
   binary scan $random H16 random
   set random [expr {([scan $random %x] % (($max-$min) + 1) + $min)}]
   close $randDev
   return $random

}

proc randStr { sLen grp alfa } { 

 set aLen [string length $alfa]; incr aLen -1
 set rs ""
 for {set i 0} {$i < $sLen} {incr i} {
   if { [expr {$i % $grp} ] == 0} { append rs " " }
   set r [randInt 0 $aLen]
   set char [string index $alfa $r]
   append rs $char
 ##puts "$i: $r $char"
 }
 return $rs

}

set alfa "ABCDEFGHIJKLMNOPQRSTUVWXYZ" set len 48 set lines 4 set fn "test.1tp"

  1. Write file:

set fh [open $fn w] puts $fh "# OTP" for {set ln 0} {$ln < $lines} {incr ln} { 

   set line [randStr $len 6 $alfa]
 ##puts "$ln :$line."
   puts $fh $line

} close $fh

  1. Read file:

puts "# File $fn:" set fh [open $fn] puts [read $fh [file size $fn]] close $fh

puts "# Done."</lang>

Output:
# True random chars for one-time pad
# File test.1tp:
# OTP
 OWCTEL SGDQEA UKEWCU PUTDEA XICBOL VVMJHD OHAXSE ZFAGDE
 QHDHKQ CCJBYF CMRCMC IXXPVM IOHQDA XIDTPX FGRIJC NPDOAT
 MYYQUV ZVKGDF ZLYKSX MBPLON RMQKQT QDYJVO LNKUFV DNKIQP
 NQOZKU MQOWHS VOQFWL EQWBFA HZQAMG JWNHGZ QERNNV GBKQTM
# Done.


Part 2: Encrypt/Decrypt

See Tcl'ers wiki: vignere Vigenere ...


Part 3: Management

  • list padfiles in directory
  • list lines / blocks between "comment"-lines in padfile (i.e. remaining usable data)

...


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