process: generate list of allowed env flags programmatically

Avoids having a separate, second source of truth on this matter.
Backport-PR-URL: #22847
PR-URL: #22638
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: addaleax

lib/internal/bootstrap/node.js

@@ -620,9 +620,45 @@
 consttest=Function.call.bind(RegExp.prototype.test);
 
 const{
- allowedV8EnvironmentFlags,
- allowedNodeEnvironmentFlags
-}=process.binding('config');
+ getOptions,
+types: { kV8Option },
+envSettings: { kAllowedInEnvironment }
+}=internalBinding('options');
+const{ options, aliases }=getOptions();
+
+constallowedV8EnvironmentFlags=[];
+constallowedNodeEnvironmentFlags=[];
+for(const[name,info]ofoptions){
+if(info.envVarSettings===kAllowedInEnvironment){
+if(info.type===kV8Option){
+allowedV8EnvironmentFlags.push(name);
+}else{
+allowedNodeEnvironmentFlags.push(name);
+}
+}
+}
+
+for(const[from,expansion]ofaliases){
+letisAccepted=true;
+for(consttoofexpansion){
+if(!to.startsWith('-'))continue;
+constrecursiveExpansion=aliases.get(to);
+if(recursiveExpansion){
+expansion.push(...recursiveExpansion);
+continue;
+}
+isAccepted=options.get(to).envVarSettings===kAllowedInEnvironment;
+if(!isAccepted)break;
+}
+if(isAccepted){
+letcanonical=from;
+if(canonical.endsWith('='))
+canonical=canonical.substr(0,canonical.length-1);
+if(canonical.endsWith(' <arg>'))
+canonical=canonical.substr(0,canonical.length-4);
+allowedNodeEnvironmentFlags.push(canonical);
+}
+}
 
 consttrimLeadingDashes=(flag)=>replace(flag,leadingDashesRegex,'');
 
@@ -660,6 +696,9 @@
 // permutations of a flag, including present/missing leading
 // dash(es) and/or underscores-for-dashes in the case of V8-specific
 // flags. Strips any values after `=`, inclusive.
+// TODO(addaleax): It might be more flexible to run the option parser
+// on a dummy option set and see whether it rejects the argument or
+// not.
 if(typeofkey==='string'){
 key=replace(key,trailingValuesRegex,'');
 if(test(leadingDashesRegex,key)){

src/node.cc

@@ -597,68 +597,6 @@ const char* signo_string(int signo) {
  }
 }
 
-// These are all flags available for use with NODE_OPTIONS.
-//
-// Disallowed flags:
-// These flags cause Node to do things other than run scripts:
-// --version / -v
-// --eval / -e
-// --print / -p
-// --check / -c
-// --interactive / -i
-// --prof-process
-// --v8-options
-// These flags are disallowed because security:
-// --preserve-symlinks
-constchar* const environment_flags[] = {
-// Node options, sorted in `node --help` order for ease of comparison.
-"--enable-fips",
-"--experimental-modules",
-"--experimenatl-repl-await",
-"--experimental-vm-modules",
-"--experimental-worker",
-"--force-fips",
-"--icu-data-dir",
-"--inspect",
-"--inspect-brk",
-"--inspect-port",
-"--loader",
-"--napi-modules",
-"--no-deprecation",
-"--no-force-async-hooks-checks",
-"--no-warnings",
-"--openssl-config",
-"--pending-deprecation",
-"--redirect-warnings",
-"--require",
-"--throw-deprecation",
-"--tls-cipher-list",
-"--trace-deprecation",
-"--trace-event-categories",
-"--trace-event-file-pattern",
-"--trace-events-enabled",
-"--trace-sync-io",
-"--trace-warnings",
-"--track-heap-objects",
-"--use-bundled-ca",
-"--use-openssl-ca",
-"--v8-pool-size",
-"--zero-fill-buffers",
-"-r"
-};
-
-// V8 options (define with '_', which allows '-' or '_')
-constchar* const v8_environment_flags[] = {
-"--abort_on_uncaught_exception",
-"--max_old_space_size",
-"--perf_basic_prof",
-"--perf_prof",
-"--stack_trace_limit",
-};
-
-int v8_environment_flags_count = arraysize(v8_environment_flags);
-int environment_flags_count = arraysize(environment_flags);
-
 // Look up environment variable unless running as setuid root.
 boolSafeGetenv(constchar* key, std::string* text) {
 #if !defined(__CloudABI__) && !defined(_WIN32)

src/node_config.cc

@@ -5,7 +5,6 @@
 
 namespacenode {
 
-using v8::Array;
 using v8::Boolean;
 using v8::Context;
 using v8::Integer;
@@ -137,22 +136,6 @@ static void Initialize(Local<Object> target,
 READONLY_PROPERTY(debug_options_obj,
 "inspectorEnabled",
 Boolean::New(isolate, debug_options->inspector_enabled));
-
- Local<Array> environmentFlags = Array::New(env->isolate(),
- environment_flags_count);
-READONLY_PROPERTY(target, "allowedNodeEnvironmentFlags", environmentFlags);
-for (int i = 0; i < environment_flags_count; ++i) {
- environmentFlags->Set(i, OneByteString(env->isolate(),
- environment_flags[i]));
- }
-
- Local<Array> v8EnvironmentFlags = Array::New(env->isolate(),
- v8_environment_flags_count);
-READONLY_PROPERTY(target, "allowedV8EnvironmentFlags", v8EnvironmentFlags);
-for (int i = 0; i < v8_environment_flags_count; ++i) {
- v8EnvironmentFlags->Set(i, OneByteString(env->isolate(),
- v8_environment_flags[i]));
- }
 } // InitConfig
 
 } // namespace node

src/node_internals.h

@@ -180,11 +180,6 @@ extern bool v8_initialized;
 extern Mutex per_process_opts_mutex;
 extern std::shared_ptr<PerProcessOptions> per_process_opts;
 
-externconstchar* const environment_flags[];
-externint environment_flags_count;
-externconstchar* const v8_environment_flags[];
-externint v8_environment_flags_count;
-
 // Forward declaration
 classEnvironment;
 

test/parallel/test-process-env-allowed-flags.js

@@ -6,8 +6,6 @@ require('../common');
 // assert legit flags are allowed, and bogus flags are disallowed
 {
 constgoodFlags=[
-'--inspect-brk',
-'inspect-brk',
 '--perf_basic_prof',
 '--perf-basic-prof',
 'perf-basic-prof',
@@ -17,8 +15,11 @@ require('../common');
 '-r',
 'r',
 '--stack-trace-limit=100',
-'--stack-trace-limit=-=xX_nodejs_Xx=-'
-];
+'--stack-trace-limit=-=xX_nodejs_Xx=-',
+].concat(process.config.variables.v8_enable_inspector ? [
+'--inspect-brk',
+'inspect-brk',
+] : []);
 
 constbadFlags=[
 '--inspect_brk',
@@ -50,7 +51,7 @@ require('../common');
 // assert all "canonical" flags begin with dash(es)
 {
 process.allowedNodeEnvironmentFlags.forEach((flag)=>{
-assert(/^--?[a-z8_-]+$/.test(flag),`Unexpected format for flag ${flag}`);
+assert(/^--?[a-z28_-]+$/.test(flag),`Unexpected format for flag ${flag}`);
 });
 }