mirrors/CyberChef
1
0
Fork 0
mirror of https://github.com/gchq/CyberChef.git synced 2025-04-20 14:56:19 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

Updated luhn checksum to to work with base 2-36

Browse source
This commit is contained in:
Pascal Burri 2024-10-26 15:49:24 +02:00
parent d635cca210
commit 802c576c60
1 changed files with 36 additions and 17 deletions
Download patch file Download diff file Expand all files Collapse all files

51
src/core/operations/LuhnChecksum.mjs
View file

@ -1,5 +1,6 @@
/** /**
* @author n1073645 [n1073645@gmail.com] * @author n1073645 [n1073645@gmail.com]
* @author k3ach [k3ach@proton.me]
* @copyright Crown Copyright 2020 * @copyright Crown Copyright 2020
* @license Apache-2.0 * @license Apache-2.0
*/ */
@ -20,11 +21,17 @@ class LuhnChecksum extends Operation {
this.name = "Luhn Checksum"; this.name = "Luhn Checksum";
this.module = "Default"; this.module = "Default";
this.description = "The Luhn algorithm, also known as the modulus 10 or mod 10 algorithm, is a simple checksum formula used to validate a variety of identification numbers, such as credit card numbers, IMEI numbers and Canadian Social Insurance Numbers."; this.description = "The Luhn mod N algorithm is an extension to the Luhn algorithm (also known as mod 10 algorithm) that allows it to work with sequences of values in any even-numbered base. This can be useful when a check digit is required to validate an identification string composed of letters, a combination of letters and digits or any arbitrary set of N characters where N is divisible by 2.";
this.infoURL = "https://wikipedia.org/wiki/Luhn_algorithm"; this.infoURL = "https://en.wikipedia.org/wiki/Luhn_mod_N_algorithm";
this.inputType = "string"; this.inputType = "string";
this.outputType = "string"; this.outputType = "string";
this.args = []; this.args = [
{
"name": "Radix",
"type": "number",
"value": 10
}
];
} }
/** /**
@ -33,26 +40,27 @@ class LuhnChecksum extends Operation {
* @param {string} inputStr * @param {string} inputStr
* @returns {number} * @returns {number}
*/ */
checksum(inputStr) { checksum(inputStr, radix = 10) {
let even = false; let even = false;
return inputStr.split("").reverse().reduce((acc, elem) => { return inputStr.split("").reverse().reduce((acc, elem) => {
// Convert element to integer. // Convert element to an integer based on the provided radix.
let temp = parseInt(elem, 10); let temp = parseInt(elem, radix);
// If element is not an integer. // If element is not a valid number in the given radix.
if (isNaN(temp)) if (isNaN(temp)) {
throw new OperationError("Character: " + elem + " is not a digit."); throw new Error("Character: " + elem + " is not valid in radix " + radix + ".");
}
// If element is in an even position // If element is in an even position
if (even) { if (even) {
// Double the element and add the quotient and remainder together. // Double the element and sum the quotient and remainder.
temp = 2 * elem; temp = 2 * temp;
temp = Math.floor(temp/10) + (temp % 10); temp = Math.floor(temp / radix) + (temp % radix);
} }
even = !even; even = !even;
return acc + temp; return acc + temp;
}, 0) % 10; }, 0) % radix; // Use radix as the modulus base
} }
/** /**
@ -63,9 +71,20 @@ class LuhnChecksum extends Operation {
run(input, args) { run(input, args) {
if (!input) return ""; if (!input) return "";
const checkSum = this.checksum(input); let radix = args[0];
let checkDigit = this.checksum(input + "0");
checkDigit = checkDigit === 0 ? 0 : (10-checkDigit); if (radix < 2 || radix > 36) {
throw new OperationError("Error: Radix argument must be between 2 and 36");
}
if (radix % 2 != 0) {
throw new OperationError("Error: Radix argument must be divisible by 2");
}
const checkSum = this.checksum(input, radix).toString(radix);
let checkDigit = this.checksum(input + "0", radix);
checkDigit = checkDigit === 0 ? 0 : (radix - checkDigit);
checkDigit = checkDigit.toString(radix)
return `Checksum: ${checkSum} return `Checksum: ${checkSum}
Checkdigit: ${checkDigit} Checkdigit: ${checkDigit}