Big Change Update

uBlock0.chromium/js/resources/replace-argument.js

@@ -0,0 +1,120 @@
+/*******************************************************************************
+
+    uBlock Origin - a comprehensive, efficient content blocker
+    Copyright (C) 2019-present Raymond Hill
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see {http://www.gnu.org/licenses/}.
+
+    Home: https://github.com/gorhill/uBlock
+
+*/
+
+import { parseReplaceFn } from './parse-replace.js';
+import { proxyApplyFn } from './proxy-apply.js';
+import { registerScriptlet } from './base.js';
+import { safeSelf } from './safe-self.js';
+import { validateConstantFn } from './set-constant.js';
+
+/**
+ * @scriptlet trusted-replace-argument.js
+ * 
+ * @description
+ * Replace an argument passed to a method. Requires a trusted source.
+ * 
+ * @param propChain
+ * The property chain to the function which argument must be replaced when
+ * called.
+ * 
+ * @param argposRaw
+ * The zero-based position of the argument in the argument list. Use a negative
+ * number for a position relative to the last argument. Use literal `this` to
+ * replace the value used in `prototype`-based methods.
+ * 
+ * @param argraw
+ * The replacement value, validated using the same heuristic as with the
+ * `set-constant.js` scriptlet.
+ * If the replacement value matches `json:...`, the value will be the
+ * json-parsed string after `json:`.
+ * If the replacement value matches `repl:/.../.../`, the target argument will
+ * be replaced according the regex-replacement directive following `repl:`
+ * 
+ * @param [, condition, pattern]
+ * Optional. The replacement will occur only when pattern matches the target
+ * argument.
+ * 
+ * */
+
+export function trustedReplaceArgument(
+    propChain = '',
+    argposRaw = '',
+    argraw = ''
+) {
+    if ( propChain === '' ) { return; }
+    const safe = safeSelf();
+    const logPrefix = safe.makeLogPrefix('trusted-replace-argument', propChain, argposRaw, argraw);
+    const argoffset = parseInt(argposRaw, 10) || 0;
+    const extraArgs = safe.getExtraArgs(Array.from(arguments), 3);
+    const replacer = argraw.startsWith('repl:/') &&
+        parseReplaceFn(argraw.slice(5)) || undefined;
+    const value = replacer === undefined &&
+        validateConstantFn(true, argraw, extraArgs) || undefined;
+    const reCondition = extraArgs.condition
+        ? safe.patternToRegex(extraArgs.condition)
+        : /^/;
+    const getArg = context => {
+        if ( argposRaw === 'this' ) { return context.thisArg; }
+        const { callArgs } = context;
+        const argpos = argoffset >= 0 ? argoffset : callArgs.length - argoffset;
+        if ( argpos < 0 || argpos >= callArgs.length ) { return; }
+        context.private = { argpos };
+        return callArgs[argpos];
+    };
+    const setArg = (context, value) => {
+        if ( argposRaw === 'this' ) {
+            if ( value !== context.thisArg ) {
+                context.thisArg = value;
+            }
+        } else if ( context.private ) {
+            context.callArgs[context.private.argpos] = value;
+        }
+    };
+    proxyApplyFn(propChain, function(context) {
+        if ( argposRaw === '' ) {
+            safe.uboLog(logPrefix, `Arguments:\n${context.callArgs.join('\n')}`);
+            return context.reflect();
+        }
+        const argBefore = getArg(context);
+        if ( safe.RegExp_test.call(reCondition, argBefore) === false ) {
+            return context.reflect();
+        }
+        const argAfter = replacer && typeof argBefore === 'string'
+            ? argBefore.replace(replacer.re, replacer.replacement)
+            : value;
+        if ( argAfter !== argBefore ) {
+            setArg(context, argAfter);
+            safe.uboLog(logPrefix, `Replaced argument:\nBefore: ${JSON.stringify(argBefore)}\nAfter: ${argAfter}`);
+        }
+        return context.reflect();
+    });
+}
+registerScriptlet(trustedReplaceArgument, {
+    name: 'trusted-replace-argument.js',
+    requiresTrust: true,
+    dependencies: [
+        parseReplaceFn,
+        proxyApplyFn,
+        safeSelf,
+        validateConstantFn,
+    ],
+});