permission: guard UDP handle adoption

Author: RafaelGSS

src/udp_wrap.cc

@@ -325,6 +325,7 @@ void UDPWrap::DoBind(const FunctionCallbackInfo<Value>& args, int family) {
     err = uv_udp_bind(&wrap->handle_,
                       reinterpret_cast<const sockaddr*>(&addr_storage),
                       flags);
+    if (err == 0) wrap->net_permission_granted_ = true;
   }
 
   if (err == 0)
@@ -358,6 +359,7 @@ void UDPWrap::DoConnect(const FunctionCallbackInfo<Value>& args, int family) {
   if (err == 0) {
     err = uv_udp_connect(&wrap->handle_,
                          reinterpret_cast<const sockaddr*>(&addr_storage));
+    if (err == 0) wrap->net_permission_granted_ = true;
   }
 
   args.GetReturnValue().Set(err);
@@ -368,9 +370,14 @@ void UDPWrap::Open(const FunctionCallbackInfo<Value>& args) {
   UDPWrap* wrap;
   ASSIGN_OR_RETURN_UNWRAP(
       &wrap, args.This(), args.GetReturnValue().Set(UV_EBADF));
+  Environment* env = wrap->env();
+
+  THROW_IF_INSUFFICIENT_PERMISSIONS(env, permission::PermissionScope::kNet, "");
+
   CHECK(args[0]->IsNumber());
   int fd = FromV8Value<int>(args[0]);
   int err = uv_udp_open(&wrap->handle_, fd);
+  if (err == 0) wrap->net_permission_granted_ = true;
 
   args.GetReturnValue().Set(err);
 }
@@ -697,6 +704,13 @@ void UDPWrapBase::RecvStart(const FunctionCallbackInfo<Value>& args) {
 
 int UDPWrap::RecvStart() {
   if (IsHandleClosing()) return UV_EBADF;
+
+  if (!net_permission_granted_) {
+    THROW_IF_INSUFFICIENT_PERMISSIONS(
+        env(), permission::PermissionScope::kNet, "", UV_EACCES);
+    net_permission_granted_ = true;
+  }
+
   int err = uv_udp_recv_start(&handle_, OnAlloc, OnRecv);
   // UV_EALREADY means that the socket is already bound but that's okay
   if (err == UV_EALREADY)

src/udp_wrap.h

@@ -214,6 +214,7 @@ class UDPWrap final : public HandleWrap,
 
   uv_udp_t handle_;
 
+  bool net_permission_granted_ = false;
   bool current_send_has_callback_;
   v8::Local<v8::Object> current_send_req_wrap_;
 };

test/parallel/test-permission-net-udp-handle.js

@@ -0,0 +1,135 @@
+// Flags: --expose-internals
+'use strict';
+
+const common = require('../common');
+if (common.isWindows) {
+  common.skip('Sending dgram sockets to child processes is not supported');
+}
+
+const assert = require('assert');
+const dgram = require('dgram');
+const { fork, spawn } = require('child_process');
+
+const mode = process.argv[2];
+const kStateSymbol = mode === undefined ?
+  require('internal/dgram').kStateSymbol : undefined;
+
+if (mode === 'ipc-denied') {
+  process.on('message', common.mustNotCall());
+  process.send('ready');
+} else if (mode === 'ipc-drop') {
+  process.once('message', common.mustCall((message, handle) => {
+    assert.strictEqual(message, 'socket');
+    assert(process.permission.has('net'));
+
+    process.permission.drop('net');
+    assert(!process.permission.has('net'));
+
+    handle.once('message', common.mustCall((data) => {
+      assert.strictEqual(data.toString(), 'after-drop');
+      handle.close();
+      process.send('received');
+    }));
+    process.send('receiving');
+  }));
+  process.send('ready');
+} else {
+  const deniedSocket = dgram.createSocket('udp4');
+  deniedSocket.bind(0, '127.0.0.1', common.mustCall(() => {
+    const child = fork(__filename, ['ipc-denied'], {
+      execArgv: ['--permission', '--allow-fs-read=*'],
+      silent: true,
+    });
+    let stderr = '';
+
+    child.stderr.setEncoding('utf8');
+    child.stderr.on('data', (chunk) => { stderr += chunk; });
+    child.once('message', common.mustCall((message) => {
+      assert.strictEqual(message, 'ready');
+      child.send('socket', deniedSocket);
+    }));
+    child.once('exit', common.mustCall((code, signal) => {
+      assert.strictEqual(code, 1);
+      assert.strictEqual(signal, null);
+      assert.match(stderr, /ERR_ACCESS_DENIED/);
+      assert.match(stderr, /permission: 'Net'/);
+      deniedSocket.close();
+    }));
+  }));
+
+  const droppedSocket = dgram.createSocket('udp4');
+  const sender = dgram.createSocket('udp4');
+  droppedSocket.bind(0, '127.0.0.1', common.mustCall(() => {
+    const child = fork(__filename, ['ipc-drop'], {
+      execArgv: [
+        '--permission',
+        '--allow-net',
+        '--allow-fs-read=*',
+      ],
+    });
+    let timer;
+
+    child.on('message', common.mustCall((message) => {
+      if (message === 'ready') {
+        child.send('socket', droppedSocket);
+      } else if (message === 'receiving') {
+        const { port } = droppedSocket.address();
+        timer = setInterval(() => {
+          sender.send('after-drop', port, '127.0.0.1');
+        }, 10);
+      } else {
+        assert.strictEqual(message, 'received');
+        clearInterval(timer);
+        sender.close();
+        droppedSocket.close();
+        child.disconnect();
+      }
+    }, 3));
+    child.once('exit', common.mustCall((code, signal) => {
+      assert.strictEqual(code, 0);
+      assert.strictEqual(signal, null);
+    }));
+  }));
+
+  const fdSocket = dgram.createSocket('udp4');
+  fdSocket.bind(0, '127.0.0.1', common.mustCall(() => {
+    const source = `
+      const assert = require('node:assert');
+      const dgram = require('node:dgram');
+      const socket = dgram.createSocket('udp4');
+      let error;
+      try {
+        socket.bind({ fd: 3 });
+      } catch (err) {
+        error = err;
+      }
+      if (error) {
+        assert.strictEqual(error.code, 'ERR_ACCESS_DENIED');
+        assert.strictEqual(error.permission, 'Net');
+        process.exit(0);
+      }
+      process.exit(1);
+    `;
+    const child = spawn(
+      process.execPath,
+      ['--permission', '--eval', source],
+      {
+        stdio: [
+          'ignore',
+          'ignore',
+          'pipe',
+          fdSocket[kStateSymbol].handle.fd,
+        ],
+      },
+    );
+    let stderr = '';
+
+    child.stderr.setEncoding('utf8');
+    child.stderr.on('data', (chunk) => { stderr += chunk; });
+    child.once('exit', common.mustCall((code, signal) => {
+      assert.strictEqual(code, 0, stderr);
+      assert.strictEqual(signal, null);
+      fdSocket.close();
+    }));
+  }));
+}