| Type: | Package |
| Title: | Classical Cryptography Methods for Words and Phrases |
| Version: | 0.1.1 |
| Description: | Classical cryptography methods for words and brief phrases. Substitution, transposition and concealment (null) ciphers are available, like Caesar, Vigenère, Atbash, affine, simple substitution, Playfair, rail fence, Scytale, single column, bifid, trifid, and Polybius ciphers. |
| License: | GPL-3 |
| URL: | https://github.com/Luigi-Annic/ciphertext |
| BugReports: | https://github.com/Luigi-Annic/ciphertext/issues |
| Encoding: | UTF-8 |
| Depends: | R (≥ 4.3.0) |
| RoxygenNote: | 7.2.3 |
| Suggests: | testthat (≥ 3.0.0) |
| Config/testthat/edition: | 3 |
| NeedsCompilation: | no |
| Packaged: | 2025-01-10 13:19:26 UTC; luigi |
| Author: | Luigi Annicchiarico [cre, aut] |
| Maintainer: | Luigi Annicchiarico <luigi.annic@gmail.com> |
| Repository: | CRAN |
| Date/Publication: | 2025-01-10 15:10:05 UTC |
affine
Description
The affine cipher is a monoalphabetic substitutoin cipher, where each letter is enciphered with the function (ax+b) mod 26 (26 is the number of letters in the alphabet)
Usage
affine(word, a, b, encrypt = TRUE)
Arguments
word |
Word or phrase to be encrypted |
a |
First parameter. This value and 26 must be coprime |
b |
Second parameter. Magnitude of the shift |
encrypt |
If 'TRUE' (default), the program ciphers the input word, If 'FALSE', the program decrypts it. |
Value
a string
References
https://en.wikipedia.org/wiki/Affine_cipher
Examples
affine("Hello", 1, -1)
atbash
Description
The Atbash cipher is a type of monoalphabetic cipher which takes the alphabet and maps it to its reverse. It is a particular case of the affine cipher, with 'a'='b'= ('m'-1). As 'm' is the number of letters and is equal to 26, it means that 'a' = 'b' = 25. Encrypting and decrypting are not separate for this cipher.
Usage
atbash(word)
Arguments
word |
Word or phrase to be encrypted |
Value
a string
References
https://en.wikipedia.org/wiki/Atbash
Examples
atbash("abcxyz")
bifid_delastelle
Description
The bifid cipher is an encryption method that combines a substitution with a Polybius square and a transposition, and uses fractionation to achieve diffusion. It was invented by Felix Delastelle.
Usage
bifid_delastelle(input, key = "", period = 100, encrypt = TRUE)
Arguments
input |
Word or phrase to be encrypted, or character vector with the sequence of coordinate numbers if we need to decrypt |
key |
key Word for creating the modified Polybius square |
period |
period length for splitting the input phrase. If greater or equal to the length of the input then the split is not executed |
encrypt |
If 'TRUE' (default), the program ciphers the input word, If 'FALSE', the program decrypts it. |
Value
a string
References
https://en.wikipedia.org/wiki/Bifid_cipher
Examples
bifid_delastelle("dcode", key = "secret", period = 3, encrypt = TRUE)
bifid_delastelle("apiai", key = "secret", period = 3, encrypt = FALSE)
caesar
Description
caesar encryption
Usage
caesar(word, key = 1, encrypt = TRUE)
Arguments
word |
Word or phrase to be encrypted |
key |
numeric key |
encrypt |
If 'TRUE' (default), the program ciphers the input word, If 'FALSE', the program decrypts it. |
Value
a string
Examples
caesar("Hello", 1)
nullcipher
Description
A null cipher is an encryption method where the plaintext is mixed with a large amount of non-cipher material (decoy).
Usage
nullcipher(phrase, index, encrypt = FALSE)
Arguments
phrase |
Word or phrase to be decrypted |
index |
letter of interest for each word in the phrase. Also a pattern vector can be entered. |
encrypt |
Only Decryption is possible for now, but will be updated in the future |
Value
a string
References
https://en.wikipedia.org/wiki/Null_cipher
Examples
nullcipher("handy set false posts", c(1,2,3))
playfair
Description
The Playfair cipher is a symmetric method which encrypts pairs of letters using a modified Polybius square
Usage
playfair(word, key = "", added_letter = "x", encrypt = TRUE)
Arguments
word |
Word or phrase to be encrypted or decrypted |
key |
Word for creating the modified Polybius square |
added_letter |
Letter to be added in case two letters of a pair are identical; usually "x" is used |
encrypt |
If 'TRUE' (default), the program ciphers the input word, If 'FALSE', the program decrypts it. |
Value
a string
References
https://en.wikipedia.org/wiki/Playfair_cipher
Examples
playfair( "instruments", "monarchy", added_letter = "z")
playfair("gatlmzclrqtx", "monarchy", added_letter = "z", encrypt = FALSE)
polybius
Description
The polybius square is a device which associates each letter to a pair of coordinates. The letter J is excluded and replaced with I in order to get 25 letters and create a 5x5 matrix.
Usage
polybius(input, encrypt = TRUE)
Arguments
input |
Word or phrase to be encrypted, or character vector with the sequence of coordinate numbers if we need to decrypt |
encrypt |
If 'TRUE' (default), the program ciphers the input word, If 'FALSE', the program decrypts it. |
Value
a string
References
https://en.wikipedia.org/wiki/Polybius_square
Examples
polybius("hello world")
polybius("23 15 31 31 34 52 34 42 31 14", encrypt = TRUE)
railfence
Description
The rail fence is a transposition cipher where the text is written upwards and downwards diagonally (zigzag) on the rails of the fence
Usage
railfence(word, key = 3)
Arguments
word |
Word or phrase to be encrypted |
key |
numeric key (number of rails) |
Value
a string
References
https://en.wikipedia.org/wiki/Rail_fence_cipher
Examples
railfence('we are discovered flee at once',3)
scytale
Description
The Scytale is a transposition cipher The diameter of the Scytale (the number of turns) can be regarded as the key of the cipher.
Usage
scytale(word, key = 3, encrypt = TRUE)
Arguments
word |
Word or phrase to be encrypted or decrypted |
key |
Number of turns of the band |
encrypt |
If 'TRUE' (default), the program ciphers the input word, If 'FALSE', the program decrypts it. |
Value
a string
References
https://en.wikipedia.org/wiki/Scytale
Examples
scytale('we are discovered flee at once',3)
simple_substitution
Description
simple substitution cipher. Each letter is monoalphabetically associated with a different one used for the encryption.
Usage
simple_substitution(word, key = "", seed = sample(1:1000, 1))
Arguments
word |
Word or phrase to be encrypted |
key |
Word to be used as key for the encryption. If not provided, a random shuffle is performed |
seed |
Seed for reproducibility of the encryption if key is not provided |
Value
a list with custom class "cipher", which modifies the printing defaults. The list contains the initial phrase (initial), the ciphered output (encrypted), and the alphabet order (keyalphabet)
Examples
simple_substitution("hello world", seed = 1234)
simple_substitution("hello world", key = "zebras")
singlecolumn
Description
In a columnar transposition cipher, the message is written out in rows of a fixed length, and then read out again column by column. The order of the column follows the alphabetical order of the letters present in the key
Usage
singlecolumn(word, key, rm.blanks = TRUE)
Arguments
word |
Word or phrase to be encrypted |
key |
word key: for example, the key "bcea" suggests that the column order is "2-3-4-1" |
rm.blanks |
Should spaces between words be removed? By default set to 'TRUE' |
Value
a string
References
https://www.geeksforgeeks.org/columnar-transposition-cipher/
Examples
singlecolumn("This is wikipedia", "cipher")
trifid_delastelle
Description
The trifid cipher is an encryption method that uses a 3-dimensional grid It was invented by Felix Delastelle in 1902. As a 3x3x3 grid is used, 27 character are needed. Thus, we use all the 26 alphabet letter and add the "+" sign at the bottom.
Usage
trifid_delastelle(input, key = "", period = 100, encrypt = TRUE)
Arguments
input |
Word or phrase to be encrypted, or character vector with the sequence of coordinate numbers if we need to decrypt |
key |
key Word for creating the modified Polybius square |
period |
period length for splitting the input phrase. If greater or equal to the length of the input then the split is not executed |
encrypt |
If 'TRUE' (default), the program ciphers the input word, If 'FALSE', the program decrypts it. |
Value
a string
References
https://en.wikipedia.org/wiki/Trifid_cipher
Examples
trifid_delastelle("secret", key = "", period = 5, encrypt = TRUE)
trifid_delastelle("sjlkzt", key = "", period = 5, encrypt = FALSE)
vigenere
Description
Vigenère cipher is a method of encrypting alphabetic text where each letter of the plaintext is encoded with a different Caesar cipher, whose increment is determined by the corresponding letter the key
Usage
vigenere(word, key, encrypt = TRUE)
Arguments
word |
Word or phrase to be encrypted |
key |
character key |
encrypt |
If 'TRUE' (default), the program ciphers the input word, If 'FALSE', the program decrypts it. |
Value
a string
References
https://en.wikipedia.org/wiki/Vigen
Examples
vigenere("hello world", "opla")