src,permission: add --allow-net permission

Signed-off-by: RafaelGSS <[email protected]>
PR-URL: #58517
Reviewed-By: Ethan Arrowood <[email protected]>
Reviewed-By: Matteo Collina <[email protected]>
Reviewed-By: Darshan Sen <[email protected]>

Author: RafaelGSS

doc/api/cli.md

@@ -263,6 +263,38 @@ When passing a single flag with a comma a warning will be displayed.
 
 Examples can be found in the [File System Permissions][] documentation.
 
+### `--allow-net`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+> Stability: 1.1 - Active development
+
+When using the [Permission Model][], the process will not be able to access
+network by default.
+Attempts to do so will throw an `ERR_ACCESS_DENIED` unless the
+user explicitly passes the `--allow-net` flag when starting Node.js.
+
+Example:
+
+```js
+const http = require('node:http');
+// Attempt to bypass the permission
+const req = http.get('http://example.com', () => {});
+
+req.on('error', (err) => {
+  console.log('err', err);
+});
+```
+
+```console
+$ node --permission index.js
+Error: connect ERR_ACCESS_DENIED Access to this API has been restricted. Use --allow-net to manage permissions.
+  code: 'ERR_ACCESS_DENIED',
+}
+```
+
 ### `--allow-wasi`
 
 <!-- YAML
@@ -1943,6 +1975,7 @@ following permissions are restricted:
 
 * File System - manageable through
   [`--allow-fs-read`][], [`--allow-fs-write`][] flags
+* Network - manageable through [`--allow-net`][] flag
 * Child Process - manageable through [`--allow-child-process`][] flag
 * Worker Threads - manageable through [`--allow-worker`][] flag
 * WASI - manageable through [`--allow-wasi`][] flag
@@ -3297,6 +3330,7 @@ one is included in the list below.
 * `--allow-child-process`
 * `--allow-fs-read`
 * `--allow-fs-write`
+* `--allow-net`
 * `--allow-wasi`
 * `--allow-worker`
 * `--conditions`, `-C`
@@ -3899,6 +3933,7 @@ node --stack-trace-limit=12 -p -e "Error.stackTraceLimit" # prints 12
 [`--allow-child-process`]: #--allow-child-process
 [`--allow-fs-read`]: #--allow-fs-read
 [`--allow-fs-write`]: #--allow-fs-write
+[`--allow-net`]: #--allow-net
 [`--allow-wasi`]: #--allow-wasi
 [`--allow-worker`]: #--allow-worker
 [`--build-snapshot`]: #--build-snapshot

doc/api/permissions.md

@@ -51,9 +51,9 @@ The available permissions are documented by the [`--permission`][]
 flag.
 
 When starting Node.js with `--permission`,
-the ability to access the file system through the `fs` module, spawn processes,
-use `node:worker_threads`, use native addons, use WASI, and enable the runtime inspector
-will be restricted.
+the ability to access the file system through the `fs` module, access the network,
+spawn processes, use `node:worker_threads`, use native addons, use WASI, and
+enable the runtime inspector will be restricted.
 
 ```console
 $ node --permission index.js
@@ -69,7 +69,8 @@ Error: Access to this API has been restricted
 Allowing access to spawning a process and creating worker threads can be done
 using the [`--allow-child-process`][] and [`--allow-worker`][] respectively.
 
-To allow native addons when using permission model, use the [`--allow-addons`][]
+To allow network access, use [`--allow-net`][] and for allowing native addons
+when using permission model, use the [`--allow-addons`][]
 flag. For WASI, use the [`--allow-wasi`][] flag.
 
 #### Runtime API
@@ -197,6 +198,7 @@ There are constraints you need to know before using this system:
 * The model does not inherit to a child node process or a worker thread.
 * When using the Permission Model the following features will be restricted:
   * Native modules
+  * Network
   * Child process
   * Worker Threads
   * Inspector protocol
@@ -227,6 +229,7 @@ There are constraints you need to know before using this system:
 [`--allow-child-process`]: cli.md#--allow-child-process
 [`--allow-fs-read`]: cli.md#--allow-fs-read
 [`--allow-fs-write`]: cli.md#--allow-fs-write
+[`--allow-net`]: cli.md#--allow-net
 [`--allow-wasi`]: cli.md#--allow-wasi
 [`--allow-worker`]: cli.md#--allow-worker
 [`--permission`]: cli.md#--permission

doc/node-config-schema.json

@@ -45,6 +45,9 @@
             }
           ]
         },
+        "allow-net": {
+          "type": "boolean"
+        },
         "allow-wasi": {
           "type": "boolean"
         },

doc/node.1

@@ -85,6 +85,9 @@ Allow using native addons when using the permission model.
 .It Fl -allow-child-process
 Allow spawning process when using the permission model.
 .
+.It Fl -allow-net
+Allow network access when using the permission model.
+.
 .It Fl -allow-wasi
 Allow execution of WASI when using the permission model.
 .

lib/internal/errors.js

@@ -113,6 +113,10 @@ function setInternalPrepareStackTrace(callback) {
   internalPrepareStackTrace = callback;
 }
 
+function isPermissionModelError(err) {
+  return typeof err !== 'number' && err.code && err.code === 'ERR_ACCESS_DENIED';
+}
+
 /**
  * Every realm has its own prepareStackTraceCallback. When `error.stack` is
  * accessed, if the error is created in a shadow realm, the shadow realm's
@@ -762,17 +766,23 @@ class ExceptionWithHostPort extends Error {
     // This can be replaced with [ code ] = errmap.get(err) when this method
     // is no longer exposed to user land.
     util ??= require('util');
-    const code = util.getSystemErrorName(err);
+    let code;
     let details = '';
-    if (port && port > 0) {
-      details = ` ${address}:${port}`;
-    } else if (address) {
-      details = ` ${address}`;
-    }
-    if (additional) {
-      details += ` - Local (${additional})`;
+    // True when permission model is enabled
+    if (isPermissionModelError(err)) {
+      code = err.code;
+      details = ` ${err.message}`;
+    } else {
+      code = util.getSystemErrorName(err);
+      if (port && port > 0) {
+        details = ` ${address}:${port}`;
+      } else if (address) {
+        details = ` ${address}`;
+      }
+      if (additional) {
+        details += ` - Local (${additional})`;
+      }
     }
-
     super(`${syscall} ${code}${details}`);
 
     this.errno = err;
@@ -798,7 +808,7 @@ class DNSException extends Error {
   constructor(code, syscall, hostname) {
     let errno;
     // If `code` is of type number, it is a libuv error number, else it is a
-    // c-ares error code.
+    // c-ares/permission model error code.
     // TODO(joyeecheung): translate c-ares error codes into numeric ones and
     // make them available in a property that's not error.errno (since they
     // can be in conflict with libuv error codes). Also make sure
@@ -813,6 +823,9 @@ class DNSException extends Error {
       } else {
         code = lazyInternalUtil().getSystemErrorName(code);
       }
+    } else if (isPermissionModelError(code)) {
+      // Expects a ERR_ACCESS_DENIED object
+      code = code.code;
     }
     super(`${syscall} ${code}${hostname ? ` ${hostname}` : ''}`);
     this.errno = errno;

lib/internal/process/pre_execution.js

@@ -600,6 +600,17 @@ function initializePermission() {
       }
     }
 
+    const experimentalWarnFlags = [
+      '--allow-net',
+    ];
+    for (const flag of experimentalWarnFlags) {
+      if (getOptionValue(flag)) {
+        process.emitWarning(
+          `The flag ${flag} is under experimental phase.`,
+          'ExperimentalWarning');
+      }
+    }
+
     ObjectDefineProperty(process, 'permission', {
       __proto__: null,
       enumerable: true,
@@ -614,6 +625,7 @@ function initializePermission() {
       '--allow-fs-write',
       '--allow-addons',
       '--allow-child-process',
+      '--allow-net',
       '--allow-wasi',
       '--allow-worker',
     ];

node.gyp

@@ -163,6 +163,7 @@
       'src/permission/permission.cc',
       'src/permission/wasi_permission.cc',
       'src/permission/worker_permission.cc',
+      'src/permission/net_permission.cc',
       'src/pipe_wrap.cc',
       'src/process_wrap.cc',
       'src/signal_wrap.cc',
@@ -292,6 +293,7 @@
       'src/permission/permission.h',
       'src/permission/wasi_permission.h',
       'src/permission/worker_permission.h',
+      'src/permission/net_permission.h',
       'src/pipe_wrap.h',
       'src/req_wrap.h',
       'src/req_wrap-inl.h',

src/cares_wrap.cc

@@ -1613,6 +1613,16 @@ Maybe<int> SoaTraits::Parse(QuerySoaWrap* wrap,
 }
 
 int ReverseTraits::Send(QueryReverseWrap* wrap, const char* name) {
+  permission::PermissionScope scope = permission::PermissionScope::kNet;
+  Environment* env_holder = wrap->env();
+
+  if (!env_holder->permission()->is_granted(env_holder, scope, name))
+      [[unlikely]] {
+    wrap->QueuePermissionModelResponseCallback(name);
+    // Error will be returned in the callback
+    return ARES_SUCCESS;
+  }
+
   int length, family;
   char address_buffer[sizeof(struct in6_addr)];
 
@@ -1851,6 +1861,10 @@ void GetAddrInfo(const FunctionCallbackInfo<Value>& args) {
   CHECK(args[4]->IsUint32());
   Local<Object> req_wrap_obj = args[0].As<Object>();
   node::Utf8Value hostname(env->isolate(), args[1]);
+
+  ERR_ACCESS_DENIED_IF_INSUFFICIENT_PERMISSIONS(
+      env, permission::PermissionScope::kNet, hostname.ToStringView(), args);
+
   std::string ascii_hostname = ada::idna::to_ascii(hostname.ToStringView());
 
   int32_t flags = 0;
@@ -1925,10 +1939,18 @@ void GetNameInfo(const FunctionCallbackInfo<Value>& args) {
       TRACING_CATEGORY_NODE2(dns, native), "lookupService", req_wrap.get(),
       "ip", TRACE_STR_COPY(*ip), "port", port);
 
-  int err = req_wrap->Dispatch(uv_getnameinfo,
-                               AfterGetNameInfo,
-                               reinterpret_cast<struct sockaddr*>(&addr),
-                               NI_NAMEREQD);
+  int err = 0;
+  if (!env->permission()->is_granted(
+          env, permission::PermissionScope::kNet, ip.ToStringView()))
+      [[unlikely]] {
+    req_wrap->InsufficientPermissionError(*ip);
+  } else {
+    err = req_wrap->Dispatch(uv_getnameinfo,
+                             AfterGetNameInfo,
+                             reinterpret_cast<struct sockaddr*>(&addr),
+                             NI_NAMEREQD);
+  }
+
   if (err == 0)
     // Release ownership of the pointer allowing the ownership to be transferred
     USE(req_wrap.release());

src/cares_wrap.h

@@ -11,6 +11,7 @@
 #include "memory_tracker.h"
 #include "node.h"
 #include "node_internals.h"
+#include "permission/permission.h"
 #include "util.h"
 
 #include "ares.h"
@@ -214,6 +215,8 @@ class GetNameInfoReqWrap final : public ReqWrap<uv_getnameinfo_t> {
  public:
   GetNameInfoReqWrap(Environment* env, v8::Local<v8::Object> req_wrap_obj);
 
+  SET_INSUFFICIENT_PERMISSION_ERROR_CALLBACK(permission::PermissionScope::kNet)
+
   SET_NO_MEMORY_INFO()
   SET_MEMORY_INFO_NAME(GetNameInfoReqWrap)
   SET_SELF_SIZE(GetNameInfoReqWrap)
@@ -249,6 +252,15 @@ class QueryWrap final : public AsyncWrap {
   void AresQuery(const char* name,
                  ares_dns_class_t dnsclass,
                  ares_dns_rec_type_t type) {
+    permission::PermissionScope scope = permission::PermissionScope::kNet;
+    Environment* env_holder = env();
+
+    if (!env_holder->permission()->is_granted(env_holder, scope, name))
+        [[unlikely]] {
+      QueuePermissionModelResponseCallback(name);
+      return;
+    }
+
     channel_->EnsureServers();
     TRACE_EVENT_NESTABLE_ASYNC_BEGIN1(
       TRACING_CATEGORY_NODE2(dns, native), trace_name_, this,
@@ -262,6 +274,8 @@ class QueryWrap final : public AsyncWrap {
                       nullptr);
   }
 
+  SET_INSUFFICIENT_PERMISSION_ERROR_CALLBACK(permission::PermissionScope::kNet)
+
   void ParseError(int status) {
     CHECK_NE(status, ARES_SUCCESS);
     v8::HandleScope handle_scope(env()->isolate());
@@ -356,6 +370,20 @@ class QueryWrap final : public AsyncWrap {
     wrap->QueueResponseCallback(status);
   }
 
+  void QueuePermissionModelResponseCallback(const char* resource) {
+    BaseObjectPtr<QueryWrap<Traits>> strong_ref{this};
+    const std::string res{resource};
+    env()->SetImmediate([this, strong_ref, res](Environment*) {
+      InsufficientPermissionError(res);
+
+      // Delete once strong_ref goes out of scope.
+      Detach();
+    });
+
+    channel_->set_query_last_ok(true);
+    channel_->ModifyActivityQueryCount(-1);
+  }
+
   void QueueResponseCallback(int status) {
     BaseObjectPtr<QueryWrap<Traits>> strong_ref{this};
     env()->SetImmediate([this, strong_ref](Environment*) {

src/env.cc

@@ -958,6 +958,10 @@ Environment::Environment(IsolateData* isolate_data,
                           options_->allow_fs_write,
                           permission::PermissionScope::kFileSystemWrite);
     }
+
+    if (options_->allow_net) {
+      permission()->Apply(this, {"*"}, permission::PermissionScope::kNet);
+    }
   }
 }
 

src/node_options.cc

@@ -565,6 +565,10 @@ EnvironmentOptionsParser::EnvironmentOptionsParser() {
             "allow use of child process when any permissions are set",
             &EnvironmentOptions::allow_child_process,
             kAllowedInEnvvar);
+  AddOption("--allow-net",
+            "allow use of network when any permissions are set",
+            &EnvironmentOptions::allow_net,
+            kAllowedInEnvvar);
   AddOption("--allow-wasi",
             "allow wasi when any permissions are set",
             &EnvironmentOptions::allow_wasi,

src/node_options.h

@@ -142,6 +142,7 @@ class EnvironmentOptions : public Options {
   std::vector<std::string> allow_fs_write;
   bool allow_addons = false;
   bool allow_child_process = false;
+  bool allow_net = false;
   bool allow_wasi = false;
   bool allow_worker_threads = false;
   bool experimental_repl_await = true;

src/permission/net_permission.cc

@@ -0,0 +1,23 @@
+#include "net_permission.h"
+
+#include <iostream>
+#include <string>
+
+namespace node {
+
+namespace permission {
+
+void NetPermission::Apply(Environment* env,
+                          const std::vector<std::string>& allow,
+                          PermissionScope scope) {
+  allow_net_ = true;
+}
+
+bool NetPermission::is_granted(Environment* env,
+                               PermissionScope perm,
+                               const std::string_view& param) const {
+  return allow_net_;
+}
+
+}  // namespace permission
+}  // namespace node