Add new operation: Insert bytes

src/core/operations/InsertBytes.mjs

@@ -0,0 +1,81 @@
+/**
+ * @author Didier Stevens [didier.stevens@gmail.com]
+ * @copyright Crown Copyright 2022
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation.mjs";
+import OperationError from "../errors/OperationError.mjs";
+import {BITWISE_OP_DELIMS} from "../lib/BitwiseOp.mjs";
+import Utils from "../Utils.mjs";
+
+/**
+ * Insert bytes operation
+ */
+class InsertBytes extends Operation {
+
+    /**
+     * InsertBytes constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Insert bytes";
+        this.module = "Default";
+        this.description = "Insert bytes at arbitrary position. Options 'from end' and 'overwrite' available.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.args = [
+            {
+                "name": "Bytes",
+                "type": "toggleString",
+                "value": "",
+                "toggleValues": BITWISE_OP_DELIMS
+            },
+            {
+                "name": "Start",
+                "type": "number",
+                "value": 0
+            },
+            {
+                "name": "From end",
+                "type": "boolean",
+                "value": false
+            },
+            {
+                "name": "Overwrite",
+                "type": "boolean",
+                "value": false
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    run(input, args) {
+        const value = Utils.convertToByteArray(args[0].string || "", args[0].option);
+        let start = args[1];
+        const fromend = args[2];
+        const overwrite = args[3];
+
+        if (start < 0)
+            throw new OperationError("Start must not be negative");
+        if (start > input.length)
+            throw new OperationError("Start must not be bigger than input");
+        if (fromend)
+            start = input.length - start;
+        const left = input.slice(0, start);
+        let right = input.slice(start);
+        if (overwrite)
+            right = right.slice(value.length);
+
+        return left.concat(value, right);
+    }
+
+}
+
+export default InsertBytes;