Question

In: Computer Science

Part 1: Design a Cipher allow user to use a “key” to encrypt and decrypt the...

  • Part 1: Design a Cipher allow user to use a “key” to encrypt and decrypt the message.

  • Use at least two ciphers combined to design your own cipher
  • Specify the min. and max. length of the message user can enter to encrypt
  • Specify the length of the “key” user can enter to encrypt and decrypt the message

  • Part 2: Programme the cipher and make it available to validate. Cleartext for the original programming scripts has to submitted. A frontend webpage is provided to allow for validation of the programme and the cipher. Provide a frontend interface for your professor to validate the design with clear instructions (like the length of the input message and key). You can use java or HTML.User enter the message with the key of his/her choice, your cipher will convert them to ciphertext.User cut and paste the ciphertext to your decryption session and input the same “key”, the original message is decrypted and is the same as what the user enters in the encryption session.

Solutions

Expert Solution

Code to encrypt and decrypt the message.

<html>
<head>
    <title> Caesar Cipher</title>
</head>

<body background="https://cdn.pixabay.com/photo/2016/08/13/16/49/computer-1591018_1280.jpg">
    <center>
        <h1><Strong>
                <font face="" color="white" >JAVASCRIPT CODING
            </strong></font>
        </h1>

        <h2><U><font color= "grey" >Caesar Cipher</U></font></h2>
        <script type="text/javascript">
            function Encrypt() {
                plaintext = document.getElementById("p").value.toLowerCase();
                if (plaintext.length < 1) { alert("please enter some plaintext"); return; }
                var shift = parseInt(document.getElementById("key").value);
                ciphertext = ""; var re = /[a-z]/;
                for (i = 0; i < plaintext.length; i++) {
                    if (re.test(plaintext.charAt(i)))
                        ciphertext += String.fromCharCode((plaintext.charCodeAt(i) - 97 + shift) % 26 + 97);
                    else
                        ciphertext += plaintext.charAt(i);
                }
                document.getElementById("c").value = ciphertext;
            }

            function Decrypt(f) {
                ciphertext = document.getElementById("c").value.toLowerCase();
                // do some error checking 
                if (ciphertext.length < 1) { alert("please enter some ciphertext"); return; }
                var shift = parseInt(document.getElementById("key").value);
                plaintext = ""; var re = /[a-z]/;
                for (i = 0; i < ciphertext.length; i++) {
                    if (re.test(ciphertext.charAt(i))) plaintext += String.fromCharCode((ciphertext.charCodeAt(i) - 97 + 26 - shift) % 26 + 97);
                    else plaintext += ciphertext.charAt(i);
                }
                document.getElementById("p").value = plaintext;
            } 
        </script>

        <h3><b><U>
                    <Font color="black" face="Serif"> Plain text</Font>
                </U></b></h3><br />
        <textarea id="p" name="p" rows="3" cols="50" placeholder=" Here type your plaintext."></textarea>
        <p> shift: <select id="key" name="key" size="1">
                <option value="0">0</option>
                <option value="1">1</option>
                <option value="2">2</option>
                <option value="3" selected="selected">3</option>
                <option value="4">4</option>
                <option value="5">5</option>
                <option value="6">6</option>
                <option value="7">7</option>
                <option value="8">8</option>
                <option value="9">9</option>
                <option value="10">10</option>
                <option value="11">11</option>
                <option value="12">12</option>
                <option value="13">13</option>
                <option value="14">14</option>
                <option value="15">15</option>
                <option value="16">16</option>
                <option value="17">17</option>
                <option value="18">18</option>
                <option value="19">19</option>
                <option value="20">20</option>
                <option value="21">21</option>
                <option value="22">22</option>
                <option value="23">23</option>
                <option value="24">24</option>
                <option value="25">25</option>
            </select></p>
        <p><input name="btnEn" value="v Encrypt v" onclick="Encrypt()" type="button" />
            <input name="btnDe" value="^ Decrypt ^" onclick="Decrypt()" type="button" /></p>
        <p><b><U><br>
                    <Font color="black" face="Arial">Ciphertext</Font> <br>
                </U></b></br><textarea id="c" name="c" rows="3" cols="50"
                placeholder="Here you will get your cipher text. "></textarea>
        </p>

    </center>

</html>

venereology answered 1 year ago
Next > < Previous

Related Solutions

1. Use a Vigenere cipher with a key of "Patton" to encrypt: "If everyone is thinking...
1. Use a Vigenere cipher with a key of "Patton" to encrypt: "If everyone is thinking alike, then somebody isn't thinking." Is this a good key? Why or why not? 2.  Calculate the index of coincidence for the result. SHOW ALL WORK PLEASE
Use Vigenère Cipher to decrypt the following plaintext with the given key key: deceptivedeceptivedeceptive plaintext: wearediscoveredsaveyourself
Use Vigenère Cipher to decrypt the following plaintext with the given key key: deceptivedeceptivedeceptive plaintext: wearediscoveredsaveyourself
Based on Rectangle transposition techniques, decrypt the following cipher text “LTHBPEEMOSRAIAESIGCVDENTUUBWEFSONES”. Then use the same key...
Based on Rectangle transposition techniques, decrypt the following cipher text “LTHBPEEMOSRAIAESIGCVDENTUUBWEFSONES”. Then use the same key to encrypt the following plain text “the automorphism group is more difficult”.           there is no given key
A, B:    Design and Implement a C# windows form application to encrypt and decrypt text....
A, B:    Design and Implement a C# windows form application to encrypt and decrypt text. The application use to receive a string and display another encrypted string. The application also decrypt the encrypted string. The approach for encryption/decryption is simple one i.e. to encrypt we will add 1 to each character, so that "hello" would become "ifmmp", and to decrypt we would subtract 1 from each character.    C:   Test and evaluate application by applying different strings.      ...
Write a Java program to encrypt the following message using the RC4 cipher using key CODES:...
Write a Java program to encrypt the following message using the RC4 cipher using key CODES: Cryptography is a method of protecting information and communications through the use of codes so that only those for whom the information is intended can read and process it. Instead of using stream length 256, we will use length 26. When encrypting, let A = 0 to Z = 25 (hence CODES = [2 14 3 4 18]). Ignore spaces and punctuations and put...
(a) Use Vigenere cipher to encrypt the message “United States Constitution” using the keyword      “covid” Given...
(a) Use Vigenere cipher to encrypt the message “United States Constitution” using the keyword      “covid” Given that the Vigenere cipher of part (a) with the same keyword was used to produce the ciphertext: VFPUSVSNBVRCNQW Find the plaintext message.        
Desc: Encrypts or decrypts a file. Input: The user supplies the character '1' to encrypt, or...
Desc: Encrypts or decrypts a file. Input: The user supplies the character '1' to encrypt, or '2' to decrypt via the keyboard.   The user also supplies the name of the source file via the keyboard.   Output: If the user wants to encrypt, the text in input file is encrypted and the encrypted text is stored in "encrypted.txt". The original file is not changed. If the user wants to decrypt, the text in input file is decrypted and the decrypted text...
1. Allow the user to vote as many times as they indicated there are voters (see...
1. Allow the user to vote as many times as they indicated there are voters (see numVoters). For each voter, you have to display the list ofcandidates and their associated id number (id numbers should start at 1, not 0). A voter votes for a candidate by entering the candidate's id number. 2. You have to devise a method for keeping tracks of the votes. 3. After all the voters have voted, you have to print out the results for...
create a program that will allow the user to enter a start value from 1 to...
create a program that will allow the user to enter a start value from 1 to 5, a stop value from 10 to 12 and a multiplier from 1 to 4. the program must display a multiplication table from the values entered. for example if the user enters: start 2, stop 10 and multiplier 3, the table should appear as follows: 3*2=6 3*3=9 3*4=12 . . . 3*10=30
Part 1: Encrypt the message CINEMA using RSA with n = 17 * 11 and e...
Part 1: Encrypt the message CINEMA using RSA with n = 17 * 11 and e = 13, use A =10...Z = 35, work in blocks of one letter each. Part 2: Decrypt the message 088-164-051-164-021-074 using the same parameters from part 1.
ADVERTISEMENT
Subjects
ADVERTISEMENT
Latest Questions
ADVERTISEMENT