ESM: Port Extract.js module

2025-04-20 14:56:19 -04:00 · 2018-05-15 16:30:17 +01:00 · 2018-05-15 16:30:17 +01:00 · b3ee251ee3
commit b3ee251ee3
parent 3c214ce17c
10 changed files with 586 additions and 333 deletions
--- a/src/core/operations/Strings.mjs
+++ b/src/core/operations/Strings.mjs
@ -0,0 +1,118 @@
+/**
+ * @author n1474335 [n1474335@gmail.com]
+ * @copyright Crown Copyright 2016
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import XRegExp from "xregexp";
+import { search } from "../lib/Extract";
+/**
+ * Strings operation
+ */
+class Strings extends Operation {
+
+    /**
+     * Strings constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Strings";
+        this.module = "Regex";
+        this.description = "Extracts all strings from the input.";
+        this.inputType = "string";
+        this.outputType = "string";
+        this.args = [
+            {
+                "name": "Encoding",
+                "type": "option",
+                "value": ["Single byte", "16-bit littleendian", "16-bit bigendian", "All"]
+            },
+            {
+                "name": "Minimum length",
+                "type": "number",
+                "value": 4
+            },
+            {
+                "name": "Match",
+                "type": "option",
+                "value": [
+                    "[ASCII]", "Alphanumeric + punctuation (A)", "All printable chars (A)", "Null-terminated strings (A)",
+                    "[Unicode]", "Alphanumeric + punctuation (U)", "All printable chars (U)", "Null-terminated strings (U)"
+                ]
+            },
+            {
+                "name": "Display total",
+                "type": "boolean",
+                "value": false
+            }
+        ];
+    }
+
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run(input, args) {
+        const encoding = args[0],
+            minLen = args[1],
+            matchType = args[2],
+            displayTotal = args[3],
+            alphanumeric = "A-Z\\d",
+            punctuation = "/\\-:.,_$%'\"()<>= !\\[\\]{}@",
+            printable = "\x20-\x7e",
+            uniAlphanumeric = "\\pL\\pN",
+            uniPunctuation = "\\pP\\pZ",
+            uniPrintable = "\\pL\\pM\\pZ\\pS\\pN\\pP";
+
+        let strings = "";
+
+        switch (matchType) {
+            case "Alphanumeric + punctuation (A)":
+                strings = `[${alphanumeric + punctuation}]`;
+                break;
+            case "All printable chars (A)":
+            case "Null-terminated strings (A)":
+                strings = `[${printable}]`;
+                break;
+            case "Alphanumeric + punctuation (U)":
+                strings = `[${uniAlphanumeric + uniPunctuation}]`;
+                break;
+            case "All printable chars (U)":
+            case "Null-terminated strings (U)":
+                strings = `[${uniPrintable}]`;
+                break;
+        }
+
+        // UTF-16 support is hacked in by allowing null bytes on either side of the matched chars
+        switch (encoding) {
+            case "All":
+                strings = `(\x00?${strings}\x00?)`;
+                break;
+            case "16-bit littleendian":
+                strings = `(${strings}\x00)`;
+                break;
+            case "16-bit bigendian":
+                strings = `(\x00${strings})`;
+                break;
+            case "Single byte":
+            default:
+                break;
+        }
+
+        strings = `${strings}{${minLen},}`;
+
+        if (matchType.includes("Null-terminated")) {
+            strings += "\x00";
+        }
+
+        const regex = new XRegExp(strings, "ig");
+
+        return search(input, regex, null, displayTotal);
+    }
+
+}
+
+export default Strings;