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689 lines (594 loc) · 23.6 KB
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#include "node_binding.h"
#include <atomic>
#include "env-inl.h"
#include "node_errors.h"
#include "node_external_reference.h"
#include "node_native_module_env.h"
#include "util.h"
#include <string>
#if HAVE_OPENSSL
#define NODE_BUILTIN_OPENSSL_MODULES(V) V(crypto) V(tls_wrap)
#else
#define NODE_BUILTIN_OPENSSL_MODULES(V)
#endif
#if NODE_HAVE_I18N_SUPPORT
#define NODE_BUILTIN_ICU_MODULES(V) V(icu)
#else
#define NODE_BUILTIN_ICU_MODULES(V)
#endif
#if HAVE_INSPECTOR
#define NODE_BUILTIN_PROFILER_MODULES(V) V(profiler)
#else
#define NODE_BUILTIN_PROFILER_MODULES(V)
#endif
#if HAVE_DTRACE || HAVE_ETW
#define NODE_BUILTIN_DTRACE_MODULES(V) V(dtrace)
#else
#define NODE_BUILTIN_DTRACE_MODULES(V)
#endif
// A list of built-in modules. In order to do module registration
// in node::Init(), need to add built-in modules in the following list.
// Then in binding::RegisterBuiltinModules(), it calls modules' registration
// function. This helps the built-in modules are loaded properly when
// node is built as static library. No need to depend on the
// __attribute__((constructor)) like mechanism in GCC.
#define NODE_BUILTIN_STANDARD_MODULES(V) \
V(async_wrap) \
V(blob) \
V(block_list) \
V(buffer) \
V(cares_wrap) \
V(config) \
V(contextify) \
V(credentials) \
V(errors) \
V(fs) \
V(fs_dir) \
V(fs_event_wrap) \
V(heap_utils) \
V(http2) \
V(http_parser) \
V(inspector) \
V(js_stream) \
V(js_udp_wrap) \
V(messaging) \
V(module_wrap) \
V(native_module) \
V(options) \
V(os) \
V(performance) \
V(pipe_wrap) \
V(process_wrap) \
V(process_methods) \
V(report) \
V(serdes) \
V(signal_wrap) \
V(spawn_sync) \
V(stream_pipe) \
V(stream_wrap) \
V(string_decoder) \
V(symbols) \
V(task_queue) \
V(tcp_wrap) \
V(timers) \
V(trace_events) \
V(tty_wrap) \
V(types) \
V(udp_wrap) \
V(url) \
V(util) \
V(uv) \
V(v8) \
V(wasi) \
V(worker) \
V(watchdog) \
V(zlib)
#define NODE_BUILTIN_MODULES(V) \
NODE_BUILTIN_STANDARD_MODULES(V) \
NODE_BUILTIN_OPENSSL_MODULES(V) \
NODE_BUILTIN_ICU_MODULES(V) \
NODE_BUILTIN_PROFILER_MODULES(V) \
NODE_BUILTIN_DTRACE_MODULES(V)
// This is used to load built-in modules. Instead of using
// __attribute__((constructor)), we call the _register_<modname>
// function for each built-in modules explicitly in
// binding::RegisterBuiltinModules(). This is only forward declaration.
// The definitions are in each module's implementation when calling
// the NODE_MODULE_CONTEXT_AWARE_INTERNAL.
#define V(modname) void _register_##modname();
NODE_BUILTIN_MODULES(V)
#undef V
#ifdef _AIX
// On AIX, dlopen() behaves differently from other operating systems, in that
// it returns unique values from each call, rather than identical values, when
// loading the same handle.
// We try to work around that by providing wrappers for the dlopen() family of
// functions, and using st_dev and st_ino for the file that is to be loaded
// as keys for a cache.
namespace node {
namespace dlwrapper {
struct dl_wrap {
uint64_t st_dev;
uint64_t st_ino;
uint64_t refcount;
void* real_handle;
struct hash {
size_t operator()(const dl_wrap* wrap) const {
return std::hash<uint64_t>()(wrap->st_dev) ^
std::hash<uint64_t>()(wrap->st_ino);
}
};
struct equal {
bool operator()(const dl_wrap* a,
const dl_wrap* b) const {
return a->st_dev == b->st_dev && a->st_ino == b->st_ino;
}
};
};
static Mutex dlhandles_mutex;
static std::unordered_set<dl_wrap*, dl_wrap::hash, dl_wrap::equal>
dlhandles;
static thread_local std::string dlerror_storage;
char* wrapped_dlerror() {
return &dlerror_storage[0];
}
void* wrapped_dlopen(const char* filename, int flags) {
CHECK_NOT_NULL(filename); // This deviates from the 'real' dlopen().
Mutex::ScopedLock lock(dlhandles_mutex);
uv_fs_t req;
auto cleanup = OnScopeLeave([&]() { uv_fs_req_cleanup(&req); });
int rc = uv_fs_stat(nullptr, &req, filename, nullptr);
if (rc != 0) {
dlerror_storage = uv_strerror(rc);
return nullptr;
}
dl_wrap search = {
req.statbuf.st_dev,
req.statbuf.st_ino,
0, nullptr
};
auto it = dlhandles.find(&search);
if (it != dlhandles.end()) {
(*it)->refcount++;
return *it;
}
void* real_handle = dlopen(filename, flags);
if (real_handle == nullptr) {
dlerror_storage = dlerror();
return nullptr;
}
dl_wrap* wrap = new dl_wrap();
wrap->st_dev = req.statbuf.st_dev;
wrap->st_ino = req.statbuf.st_ino;
wrap->refcount = 1;
wrap->real_handle = real_handle;
dlhandles.insert(wrap);
return wrap;
}
int wrapped_dlclose(void* handle) {
Mutex::ScopedLock lock(dlhandles_mutex);
dl_wrap* wrap = static_cast<dl_wrap*>(handle);
int ret = 0;
CHECK_GE(wrap->refcount, 1);
if (--wrap->refcount == 0) {
ret = dlclose(wrap->real_handle);
if (ret != 0) dlerror_storage = dlerror();
dlhandles.erase(wrap);
delete wrap;
}
return ret;
}
void* wrapped_dlsym(void* handle, const char* symbol) {
if (handle == RTLD_DEFAULT || handle == RTLD_NEXT)
return dlsym(handle, symbol);
dl_wrap* wrap = static_cast<dl_wrap*>(handle);
return dlsym(wrap->real_handle, symbol);
}
#define dlopen node::dlwrapper::wrapped_dlopen
#define dlerror node::dlwrapper::wrapped_dlerror
#define dlclose node::dlwrapper::wrapped_dlclose
#define dlsym node::dlwrapper::wrapped_dlsym
} // namespace dlwrapper
} // namespace node
#endif // _AIX
#ifdef __linux__
static bool libc_may_be_musl() {
static std::atomic_bool retval; // Cache the return value.
static std::atomic_bool has_cached_retval { false };
if (has_cached_retval) return retval;
retval = dlsym(RTLD_DEFAULT, "gnu_get_libc_version") == nullptr;
has_cached_retval = true;
return retval;
}
#else // __linux__
static bool libc_may_be_musl() { return false; }
#endif // __linux__
namespace node {
using v8::Context;
using v8::Exception;
using v8::Function;
using v8::FunctionCallbackInfo;
using v8::Local;
using v8::Object;
using v8::String;
using v8::Value;
// Globals per process
static node_module* modlist_internal;
static node_module* modlist_linked;
static thread_local node_module* thread_local_modpending;
// This is set by node::Init() which is used by embedders
bool node_is_initialized = false;
extern "C" void node_module_register(void* m) {
struct node_module* mp = reinterpret_cast<struct node_module*>(m);
if (mp->nm_flags & NM_F_INTERNAL) {
mp->nm_link = modlist_internal;
modlist_internal = mp;
} else if (!node_is_initialized) {
// "Linked" modules are included as part of the node project.
// Like builtins they are registered *before* node::Init runs.
mp->nm_flags = NM_F_LINKED;
mp->nm_link = modlist_linked;
modlist_linked = mp;
} else {
thread_local_modpending = mp;
}
}
namespace binding {
static struct global_handle_map_t {
public:
void set(void* handle, node_module* mod) {
CHECK_NE(handle, nullptr);
Mutex::ScopedLock lock(mutex_);
map_[handle].module = mod;
// We need to store this flag internally to avoid a chicken-and-egg problem
// during cleanup. By the time we actually use the flag's value,
// the shared object has been unloaded, and its memory would be gone,
// making it impossible to access fields of `mod` --
// unless `mod` *is* dynamically allocated, but we cannot know that
// without checking the flag.
map_[handle].wants_delete_module = mod->nm_flags & NM_F_DELETEME;
map_[handle].refcount++;
}
node_module* get_and_increase_refcount(void* handle) {
CHECK_NE(handle, nullptr);
Mutex::ScopedLock lock(mutex_);
auto it = map_.find(handle);
if (it == map_.end()) return nullptr;
it->second.refcount++;
return it->second.module;
}
void erase(void* handle) {
CHECK_NE(handle, nullptr);
Mutex::ScopedLock lock(mutex_);
auto it = map_.find(handle);
if (it == map_.end()) return;
CHECK_GE(it->second.refcount, 1);
if (--it->second.refcount == 0) {
if (it->second.wants_delete_module)
delete it->second.module;
map_.erase(handle);
}
}
private:
Mutex mutex_;
struct Entry {
unsigned int refcount;
bool wants_delete_module;
node_module* module;
};
std::unordered_map<void*, Entry> map_;
} global_handle_map;
DLib::DLib(const char* filename, int flags)
: filename_(filename), flags_(flags), handle_(nullptr) {}
#ifdef __POSIX__
bool DLib::Open() {
handle_ = dlopen(filename_.c_str(), flags_);
if (handle_ != nullptr) return true;
errmsg_ = dlerror();
return false;
}
void DLib::Close() {
if (handle_ == nullptr) return;
if (libc_may_be_musl()) {
// musl libc implements dlclose() as a no-op which returns 0.
// As a consequence, trying to re-load a previously closed addon at a later
// point will not call its static constructors, which Node.js uses.
// Therefore, when we may be using musl libc, we assume that the shared
// object exists indefinitely and keep it in our handle map.
return;
}
int err = dlclose(handle_);
if (err == 0) {
if (has_entry_in_global_handle_map_)
global_handle_map.erase(handle_);
}
handle_ = nullptr;
}
void* DLib::GetSymbolAddress(const char* name) {
return dlsym(handle_, name);
}
#else // !__POSIX__
bool DLib::Open() {
int ret = uv_dlopen(filename_.c_str(), &lib_);
if (ret == 0) {
handle_ = static_cast<void*>(lib_.handle);
return true;
}
errmsg_ = uv_dlerror(&lib_);
uv_dlclose(&lib_);
return false;
}
void DLib::Close() {
if (handle_ == nullptr) return;
if (has_entry_in_global_handle_map_)
global_handle_map.erase(handle_);
uv_dlclose(&lib_);
handle_ = nullptr;
}
void* DLib::GetSymbolAddress(const char* name) {
void* address;
if (0 == uv_dlsym(&lib_, name, &address)) return address;
return nullptr;
}
#endif // !__POSIX__
void DLib::SaveInGlobalHandleMap(node_module* mp) {
has_entry_in_global_handle_map_ = true;
global_handle_map.set(handle_, mp);
}
node_module* DLib::GetSavedModuleFromGlobalHandleMap() {
has_entry_in_global_handle_map_ = true;
return global_handle_map.get_and_increase_refcount(handle_);
}
using InitializerCallback = void (*)(Local<Object> exports,
Local<Value> module,
Local<Context> context);
inline InitializerCallback GetInitializerCallback(DLib* dlib) {
const char* name = "node_register_module_v" STRINGIFY(NODE_MODULE_VERSION);
return reinterpret_cast<InitializerCallback>(dlib->GetSymbolAddress(name));
}
inline napi_addon_register_func GetNapiInitializerCallback(DLib* dlib) {
const char* name =
STRINGIFY(NAPI_MODULE_INITIALIZER_BASE) STRINGIFY(NAPI_MODULE_VERSION);
return reinterpret_cast<napi_addon_register_func>(
dlib->GetSymbolAddress(name));
}
// DLOpen is process.dlopen(module, filename, flags).
// Used to load 'module.node' dynamically shared objects.
//
// FIXME(bnoordhuis) Not multi-context ready. TBD how to resolve the conflict
// when two contexts try to load the same shared object. Maybe have a shadow
// cache that's a plain C list or hash table that's shared across contexts?
void DLOpen(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
if (env->no_native_addons()) {
return THROW_ERR_DLOPEN_DISABLED(
env, "Cannot load native addon because loading addons is disabled.");
}
auto context = env->context();
CHECK_NULL(thread_local_modpending);
if (args.Length() < 2) {
return THROW_ERR_MISSING_ARGS(
env, "process.dlopen needs at least 2 arguments");
}
int32_t flags = DLib::kDefaultFlags;
if (args.Length() > 2 && !args[2]->Int32Value(context).To(&flags)) {
return THROW_ERR_INVALID_ARG_TYPE(env, "flag argument must be an integer.");
}
Local<Object> module;
Local<Object> exports;
Local<Value> exports_v;
if (!args[0]->ToObject(context).ToLocal(&module) ||
!module->Get(context, env->exports_string()).ToLocal(&exports_v) ||
!exports_v->ToObject(context).ToLocal(&exports)) {
return; // Exception pending.
}
node::Utf8Value filename(env->isolate(), args[1]); // Cast
env->TryLoadAddon(*filename, flags, [&](DLib* dlib) {
static Mutex dlib_load_mutex;
Mutex::ScopedLock lock(dlib_load_mutex);
const bool is_opened = dlib->Open();
// Objects containing v14 or later modules will have registered themselves
// on the pending list. Activate all of them now. At present, only one
// module per object is supported.
node_module* mp = thread_local_modpending;
thread_local_modpending = nullptr;
if (!is_opened) {
std::string errmsg = dlib->errmsg_.c_str();
dlib->Close();
#ifdef _WIN32
// Windows needs to add the filename into the error message
errmsg += *filename;
#endif // _WIN32
THROW_ERR_DLOPEN_FAILED(env, errmsg.c_str());
return false;
}
if (mp != nullptr) {
if (mp->nm_context_register_func == nullptr) {
if (env->force_context_aware()) {
dlib->Close();
THROW_ERR_NON_CONTEXT_AWARE_DISABLED(env);
return false;
}
}
mp->nm_dso_handle = dlib->handle_;
dlib->SaveInGlobalHandleMap(mp);
} else {
if (auto callback = GetInitializerCallback(dlib)) {
callback(exports, module, context);
return true;
} else if (auto napi_callback = GetNapiInitializerCallback(dlib)) {
napi_module_register_by_symbol(exports, module, context, napi_callback);
return true;
} else {
mp = dlib->GetSavedModuleFromGlobalHandleMap();
if (mp == nullptr || mp->nm_context_register_func == nullptr) {
dlib->Close();
char errmsg[1024];
snprintf(errmsg,
sizeof(errmsg),
"Module did not self-register: '%s'.",
*filename);
THROW_ERR_DLOPEN_FAILED(env, errmsg);
return false;
}
}
}
// -1 is used for N-API modules
if ((mp->nm_version != -1) && (mp->nm_version != NODE_MODULE_VERSION)) {
// Even if the module did self-register, it may have done so with the
// wrong version. We must only give up after having checked to see if it
// has an appropriate initializer callback.
if (auto callback = GetInitializerCallback(dlib)) {
callback(exports, module, context);
return true;
}
char errmsg[1024];
snprintf(errmsg,
sizeof(errmsg),
"The module '%s'"
"\nwas compiled against a different Node.js version using"
"\nNODE_MODULE_VERSION %d. This version of Node.js requires"
"\nNODE_MODULE_VERSION %d. Please try re-compiling or "
"re-installing\nthe module (for instance, using `npm rebuild` "
"or `npm install`).",
*filename,
mp->nm_version,
NODE_MODULE_VERSION);
// NOTE: `mp` is allocated inside of the shared library's memory, calling
// `dlclose` will deallocate it
dlib->Close();
THROW_ERR_DLOPEN_FAILED(env, errmsg);
return false;
}
CHECK_EQ(mp->nm_flags & NM_F_BUILTIN, 0);
// Do not keep the lock while running userland addon loading code.
Mutex::ScopedUnlock unlock(lock);
if (mp->nm_context_register_func != nullptr) {
mp->nm_context_register_func(exports, module, context, mp->nm_priv);
} else if (mp->nm_register_func != nullptr) {
mp->nm_register_func(exports, module, mp->nm_priv);
} else {
dlib->Close();
THROW_ERR_DLOPEN_FAILED(env, "Module has no declared entry point.");
return false;
}
return true;
});
// Tell coverity that 'handle' should not be freed when we return.
// coverity[leaked_storage]
}
inline struct node_module* FindModule(struct node_module* list,
const char* name,
int flag) {
struct node_module* mp;
for (mp = list; mp != nullptr; mp = mp->nm_link) {
if (strcmp(mp->nm_modname, name) == 0) break;
}
CHECK(mp == nullptr || (mp->nm_flags & flag) != 0);
return mp;
}
static Local<Object> InitModule(Environment* env,
node_module* mod,
Local<String> module) {
// Internal bindings don't have a "module" object, only exports.
Local<Function> ctor = env->binding_data_ctor_template()
->GetFunction(env->context())
.ToLocalChecked();
Local<Object> exports = ctor->NewInstance(env->context()).ToLocalChecked();
CHECK_NULL(mod->nm_register_func);
CHECK_NOT_NULL(mod->nm_context_register_func);
Local<Value> unused = Undefined(env->isolate());
mod->nm_context_register_func(exports, unused, env->context(), mod->nm_priv);
return exports;
}
void GetInternalBinding(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(args[0]->IsString());
Local<String> module = args[0].As<String>();
node::Utf8Value module_v(env->isolate(), module);
Local<Object> exports;
node_module* mod = FindModule(modlist_internal, *module_v, NM_F_INTERNAL);
if (mod != nullptr) {
exports = InitModule(env, mod, module);
env->internal_bindings.insert(mod);
} else if (!strcmp(*module_v, "constants")) {
exports = Object::New(env->isolate());
CHECK(
exports->SetPrototype(env->context(), Null(env->isolate())).FromJust());
DefineConstants(env->isolate(), exports);
} else if (!strcmp(*module_v, "natives")) {
exports = native_module::NativeModuleEnv::GetSourceObject(env->context());
// Legacy feature: process.binding('natives').config contains stringified
// config.gypi
CHECK(exports
->Set(env->context(),
env->config_string(),
native_module::NativeModuleEnv::GetConfigString(
env->isolate()))
.FromJust());
} else {
char errmsg[1024];
snprintf(errmsg, sizeof(errmsg), "No such module: %s", *module_v);
return THROW_ERR_INVALID_MODULE(env, errmsg);
}
args.GetReturnValue().Set(exports);
}
void GetLinkedBinding(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(args[0]->IsString());
Local<String> module_name = args[0].As<String>();
node::Utf8Value module_name_v(env->isolate(), module_name);
const char* name = *module_name_v;
node_module* mod = nullptr;
// Iterate from here to the nearest non-Worker Environment to see if there's
// a linked binding defined locally rather than through the global list.
Environment* cur_env = env;
while (mod == nullptr && cur_env != nullptr) {
Mutex::ScopedLock lock(cur_env->extra_linked_bindings_mutex());
mod = FindModule(cur_env->extra_linked_bindings_head(), name, NM_F_LINKED);
cur_env = cur_env->worker_parent_env();
}
if (mod == nullptr)
mod = FindModule(modlist_linked, name, NM_F_LINKED);
if (mod == nullptr) {
char errmsg[1024];
snprintf(errmsg,
sizeof(errmsg),
"No such module was linked: %s",
*module_name_v);
return THROW_ERR_INVALID_MODULE(env, errmsg);
}
Local<Object> module = Object::New(env->isolate());
Local<Object> exports = Object::New(env->isolate());
Local<String> exports_prop =
String::NewFromUtf8Literal(env->isolate(), "exports");
module->Set(env->context(), exports_prop, exports).Check();
if (mod->nm_context_register_func != nullptr) {
mod->nm_context_register_func(
exports, module, env->context(), mod->nm_priv);
} else if (mod->nm_register_func != nullptr) {
mod->nm_register_func(exports, module, mod->nm_priv);
} else {
return THROW_ERR_INVALID_MODULE(
env,
"Linked moduled has no declared entry point.");
}
auto effective_exports =
module->Get(env->context(), exports_prop).ToLocalChecked();
args.GetReturnValue().Set(effective_exports);
}
// Call built-in modules' _register_<module name> function to
// do module registration explicitly.
void RegisterBuiltinModules() {
#define V(modname) _register_##modname();
NODE_BUILTIN_MODULES(V)
#undef V
}
void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
registry->Register(GetLinkedBinding);
registry->Register(GetInternalBinding);
}
} // namespace binding
} // namespace node
NODE_MODULE_EXTERNAL_REFERENCE(binding,
node::binding::RegisterExternalReferences)