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#include "aliased_buffer.h"
#include "debug_utils.h"
#include "node.h"
#include "node_buffer.h"
#include "node_http2.h"
#include "node_http2_state.h"
#include "node_internals.h"
#include "node_perf.h"
#include <algorithm>
namespace node {
using v8::ArrayBuffer;
using v8::Boolean;
using v8::Context;
using v8::Float64Array;
using v8::Function;
using v8::Integer;
using v8::Number;
using v8::ObjectTemplate;
using v8::String;
using v8::Uint32;
using v8::Uint32Array;
using v8::Undefined;
using node::performance::PerformanceEntry;
namespace http2 {
namespace {
const char zero_bytes_256[256] = {};
inline Http2Stream* GetStream(Http2Session* session,
int32_t id,
nghttp2_data_source* source) {
Http2Stream* stream = static_cast<Http2Stream*>(source->ptr);
if (stream == nullptr)
stream = session->FindStream(id);
CHECK_NOT_NULL(stream);
CHECK_EQ(id, stream->id());
return stream;
}
} // anonymous namespace
// These configure the callbacks required by nghttp2 itself. There are
// two sets of callback functions, one that is used if a padding callback
// is set, and other that does not include the padding callback.
const Http2Session::Callbacks Http2Session::callback_struct_saved[2] = {
Callbacks(false),
Callbacks(true)};
// The Http2Scope object is used to queue a write to the i/o stream. It is
// used whenever any action is take on the underlying nghttp2 API that may
// push data into nghttp2 outbound data queue.
//
// For example:
//
// Http2Scope h2scope(session);
// nghttp2_submit_ping(**session, ... );
//
// When the Http2Scope passes out of scope and is deconstructed, it will
// call Http2Session::MaybeScheduleWrite().
Http2Scope::Http2Scope(Http2Stream* stream) : Http2Scope(stream->session()) {}
Http2Scope::Http2Scope(Http2Session* session) {
if (session == nullptr)
return;
if (session->flags_ & (SESSION_STATE_HAS_SCOPE |
SESSION_STATE_WRITE_SCHEDULED)) {
// There is another scope further below on the stack, or it is already
// known that a write is scheduled. In either case, there is nothing to do.
return;
}
session->flags_ |= SESSION_STATE_HAS_SCOPE;
session_ = session;
// Always keep the session object alive for at least as long as
// this scope is active.
session_handle_ = session->object();
CHECK(!session_handle_.IsEmpty());
}
Http2Scope::~Http2Scope() {
if (session_ == nullptr)
return;
session_->flags_ &= ~SESSION_STATE_HAS_SCOPE;
session_->MaybeScheduleWrite();
}
// The Http2Options object is used during the construction of Http2Session
// instances to configure an appropriate nghttp2_options struct. The class
// uses a single TypedArray instance that is shared with the JavaScript side
// to more efficiently pass values back and forth.
Http2Options::Http2Options(Environment* env, nghttp2_session_type type) {
nghttp2_option_new(&options_);
// Make sure closed connections aren't kept around, taking up memory.
// Note that this breaks the priority tree, which we don't use.
nghttp2_option_set_no_closed_streams(options_, 1);
// We manually handle flow control within a session in order to
// implement backpressure -- that is, we only send WINDOW_UPDATE
// frames to the remote peer as data is actually consumed by user
// code. This ensures that the flow of data over the connection
// does not move too quickly and limits the amount of data we
// are required to buffer.
nghttp2_option_set_no_auto_window_update(options_, 1);
// Enable built in support for receiving ALTSVC and ORIGIN frames (but
// only on client side sessions
if (type == NGHTTP2_SESSION_CLIENT) {
nghttp2_option_set_builtin_recv_extension_type(options_, NGHTTP2_ALTSVC);
nghttp2_option_set_builtin_recv_extension_type(options_, NGHTTP2_ORIGIN);
}
AliasedBuffer<uint32_t, Uint32Array>& buffer =
env->http2_state()->options_buffer;
uint32_t flags = buffer[IDX_OPTIONS_FLAGS];
if (flags & (1 << IDX_OPTIONS_MAX_DEFLATE_DYNAMIC_TABLE_SIZE)) {
nghttp2_option_set_max_deflate_dynamic_table_size(
options_,
buffer[IDX_OPTIONS_MAX_DEFLATE_DYNAMIC_TABLE_SIZE]);
}
if (flags & (1 << IDX_OPTIONS_MAX_RESERVED_REMOTE_STREAMS)) {
nghttp2_option_set_max_reserved_remote_streams(
options_,
buffer[IDX_OPTIONS_MAX_RESERVED_REMOTE_STREAMS]);
}
if (flags & (1 << IDX_OPTIONS_MAX_SEND_HEADER_BLOCK_LENGTH)) {
nghttp2_option_set_max_send_header_block_length(
options_,
buffer[IDX_OPTIONS_MAX_SEND_HEADER_BLOCK_LENGTH]);
}
// Recommended default
nghttp2_option_set_peer_max_concurrent_streams(options_, 100);
if (flags & (1 << IDX_OPTIONS_PEER_MAX_CONCURRENT_STREAMS)) {
nghttp2_option_set_peer_max_concurrent_streams(
options_,
buffer[IDX_OPTIONS_PEER_MAX_CONCURRENT_STREAMS]);
}
// The padding strategy sets the mechanism by which we determine how much
// additional frame padding to apply to DATA and HEADERS frames. Currently
// this is set on a per-session basis, but eventually we may switch to
// a per-stream setting, giving users greater control
if (flags & (1 << IDX_OPTIONS_PADDING_STRATEGY)) {
padding_strategy_type strategy =
static_cast<padding_strategy_type>(
buffer.GetValue(IDX_OPTIONS_PADDING_STRATEGY));
SetPaddingStrategy(strategy);
}
// The max header list pairs option controls the maximum number of
// header pairs the session may accept. This is a hard limit.. that is,
// if the remote peer sends more than this amount, the stream will be
// automatically closed with an RST_STREAM.
if (flags & (1 << IDX_OPTIONS_MAX_HEADER_LIST_PAIRS)) {
SetMaxHeaderPairs(buffer[IDX_OPTIONS_MAX_HEADER_LIST_PAIRS]);
}
// The HTTP2 specification places no limits on the number of HTTP2
// PING frames that can be sent. In order to prevent PINGS from being
// abused as an attack vector, however, we place a strict upper limit
// on the number of unacknowledged PINGS that can be sent at any given
// time.
if (flags & (1 << IDX_OPTIONS_MAX_OUTSTANDING_PINGS)) {
SetMaxOutstandingPings(buffer[IDX_OPTIONS_MAX_OUTSTANDING_PINGS]);
}
// The HTTP2 specification places no limits on the number of HTTP2
// SETTINGS frames that can be sent. In order to prevent PINGS from being
// abused as an attack vector, however, we place a strict upper limit
// on the number of unacknowledged SETTINGS that can be sent at any given
// time.
if (flags & (1 << IDX_OPTIONS_MAX_OUTSTANDING_SETTINGS)) {
SetMaxOutstandingSettings(buffer[IDX_OPTIONS_MAX_OUTSTANDING_SETTINGS]);
}
// The HTTP2 specification places no limits on the amount of memory
// that a session can consume. In order to prevent abuse, we place a
// cap on the amount of memory a session can consume at any given time.
// this is a credit based system. Existing streams may cause the limit
// to be temporarily exceeded but once over the limit, new streams cannot
// created.
// Important: The maxSessionMemory option in javascript is expressed in
// terms of MB increments (i.e. the value 1 == 1 MB)
if (flags & (1 << IDX_OPTIONS_MAX_SESSION_MEMORY)) {
SetMaxSessionMemory(buffer[IDX_OPTIONS_MAX_SESSION_MEMORY] * 1e6);
}
}
void Http2Session::Http2Settings::Init() {
AliasedBuffer<uint32_t, Uint32Array>& buffer =
env()->http2_state()->settings_buffer;
uint32_t flags = buffer[IDX_SETTINGS_COUNT];
size_t n = 0;
#define GRABSETTING(N, trace) \
if (flags & (1 << IDX_SETTINGS_##N)) { \
uint32_t val = buffer[IDX_SETTINGS_##N]; \
if (session_ != nullptr) \
Debug(session_, "setting " trace ": %d\n", val); \
entries_[n++] = \
nghttp2_settings_entry {NGHTTP2_SETTINGS_##N, val}; \
}
GRABSETTING(HEADER_TABLE_SIZE, "header table size");
GRABSETTING(MAX_CONCURRENT_STREAMS, "max concurrent streams");
GRABSETTING(MAX_FRAME_SIZE, "max frame size");
GRABSETTING(INITIAL_WINDOW_SIZE, "initial window size");
GRABSETTING(MAX_HEADER_LIST_SIZE, "max header list size");
GRABSETTING(ENABLE_PUSH, "enable push");
GRABSETTING(ENABLE_CONNECT_PROTOCOL, "enable connect protocol");
#undef GRABSETTING
count_ = n;
}
Http2Session::Http2Settings::Http2Settings(Environment* env,
Http2Session* session, uint64_t start_time)
: AsyncWrap(env,
env->http2settings_constructor_template()
->NewInstance(env->context())
.ToLocalChecked(),
PROVIDER_HTTP2SETTINGS),
session_(session),
startTime_(start_time) {
Init();
}
Http2Session::Http2Settings::Http2Settings(Environment* env)
: Http2Settings(env, nullptr, 0) {}
// The Http2Settings class is used to configure a SETTINGS frame that is
// to be sent to the connected peer. The settings are set using a TypedArray
// that is shared with the JavaScript side.
Http2Session::Http2Settings::Http2Settings(Http2Session* session)
: Http2Settings(session->env(), session, uv_hrtime()) {}
// Generates a Buffer that contains the serialized payload of a SETTINGS
// frame. This can be used, for instance, to create the Base64-encoded
// content of an Http2-Settings header field.
Local<Value> Http2Session::Http2Settings::Pack() {
const size_t len = count_ * 6;
Local<Value> buf = Buffer::New(env(), len).ToLocalChecked();
ssize_t ret =
nghttp2_pack_settings_payload(
reinterpret_cast<uint8_t*>(Buffer::Data(buf)), len,
&entries_[0], count_);
if (ret >= 0)
return buf;
else
return Undefined(env()->isolate());
}
// Updates the shared TypedArray with the current remote or local settings for
// the session.
void Http2Session::Http2Settings::Update(Environment* env,
Http2Session* session,
get_setting fn) {
AliasedBuffer<uint32_t, Uint32Array>& buffer =
env->http2_state()->settings_buffer;
buffer[IDX_SETTINGS_HEADER_TABLE_SIZE] =
fn(**session, NGHTTP2_SETTINGS_HEADER_TABLE_SIZE);
buffer[IDX_SETTINGS_MAX_CONCURRENT_STREAMS] =
fn(**session, NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS);
buffer[IDX_SETTINGS_INITIAL_WINDOW_SIZE] =
fn(**session, NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE);
buffer[IDX_SETTINGS_MAX_FRAME_SIZE] =
fn(**session, NGHTTP2_SETTINGS_MAX_FRAME_SIZE);
buffer[IDX_SETTINGS_MAX_HEADER_LIST_SIZE] =
fn(**session, NGHTTP2_SETTINGS_MAX_HEADER_LIST_SIZE);
buffer[IDX_SETTINGS_ENABLE_PUSH] =
fn(**session, NGHTTP2_SETTINGS_ENABLE_PUSH);
buffer[IDX_SETTINGS_ENABLE_CONNECT_PROTOCOL] =
fn(**session, NGHTTP2_SETTINGS_ENABLE_CONNECT_PROTOCOL);
}
// Initializes the shared TypedArray with the default settings values.
void Http2Session::Http2Settings::RefreshDefaults(Environment* env) {
AliasedBuffer<uint32_t, Uint32Array>& buffer =
env->http2_state()->settings_buffer;
buffer[IDX_SETTINGS_HEADER_TABLE_SIZE] =
DEFAULT_SETTINGS_HEADER_TABLE_SIZE;
buffer[IDX_SETTINGS_ENABLE_PUSH] =
DEFAULT_SETTINGS_ENABLE_PUSH;
buffer[IDX_SETTINGS_INITIAL_WINDOW_SIZE] =
DEFAULT_SETTINGS_INITIAL_WINDOW_SIZE;
buffer[IDX_SETTINGS_MAX_FRAME_SIZE] =
DEFAULT_SETTINGS_MAX_FRAME_SIZE;
buffer[IDX_SETTINGS_MAX_HEADER_LIST_SIZE] =
DEFAULT_SETTINGS_MAX_HEADER_LIST_SIZE;
buffer[IDX_SETTINGS_COUNT] =
(1 << IDX_SETTINGS_HEADER_TABLE_SIZE) |
(1 << IDX_SETTINGS_ENABLE_PUSH) |
(1 << IDX_SETTINGS_INITIAL_WINDOW_SIZE) |
(1 << IDX_SETTINGS_MAX_FRAME_SIZE) |
(1 << IDX_SETTINGS_MAX_HEADER_LIST_SIZE);
}
void Http2Session::Http2Settings::Send() {
Http2Scope h2scope(session_);
CHECK_EQ(nghttp2_submit_settings(**session_, NGHTTP2_FLAG_NONE,
&entries_[0], count_), 0);
}
void Http2Session::Http2Settings::Done(bool ack) {
uint64_t end = uv_hrtime();
double duration = (end - startTime_) / 1e6;
Local<Value> argv[2] = {
Boolean::New(env()->isolate(), ack),
Number::New(env()->isolate(), duration)
};
MakeCallback(env()->ondone_string(), arraysize(argv), argv);
delete this;
}
// The Http2Priority class initializes an appropriate nghttp2_priority_spec
// struct used when either creating a stream or updating its priority
// settings.
Http2Priority::Http2Priority(Environment* env,
Local<Value> parent,
Local<Value> weight,
Local<Value> exclusive) {
Local<Context> context = env->context();
int32_t parent_ = parent->Int32Value(context).ToChecked();
int32_t weight_ = weight->Int32Value(context).ToChecked();
bool exclusive_ = exclusive->BooleanValue(context).ToChecked();
Debug(env, DebugCategory::HTTP2STREAM,
"Http2Priority: parent: %d, weight: %d, exclusive: %d\n",
parent_, weight_, exclusive_);
nghttp2_priority_spec_init(&spec, parent_, weight_, exclusive_ ? 1 : 0);
}
const char* Http2Session::TypeName() const {
switch (session_type_) {
case NGHTTP2_SESSION_SERVER: return "server";
case NGHTTP2_SESSION_CLIENT: return "client";
default:
// This should never happen
ABORT();
}
}
// The Headers class initializes a proper array of nghttp2_nv structs
// containing the header name value pairs.
Headers::Headers(Isolate* isolate,
Local<Context> context,
Local<Array> headers) {
Local<Value> header_string = headers->Get(context, 0).ToLocalChecked();
Local<Value> header_count = headers->Get(context, 1).ToLocalChecked();
count_ = header_count.As<Uint32>()->Value();
int header_string_len = header_string.As<String>()->Length();
if (count_ == 0) {
CHECK_EQ(header_string_len, 0);
return;
}
// Allocate a single buffer with count_ nghttp2_nv structs, followed
// by the raw header data as passed from JS. This looks like:
// | possible padding | nghttp2_nv | nghttp2_nv | ... | header contents |
buf_.AllocateSufficientStorage((alignof(nghttp2_nv) - 1) +
count_ * sizeof(nghttp2_nv) +
header_string_len);
// Make sure the start address is aligned appropriately for an nghttp2_nv*.
char* start = reinterpret_cast<char*>(
ROUND_UP(reinterpret_cast<uintptr_t>(*buf_), alignof(nghttp2_nv)));
char* header_contents = start + (count_ * sizeof(nghttp2_nv));
nghttp2_nv* const nva = reinterpret_cast<nghttp2_nv*>(start);
CHECK_LE(header_contents + header_string_len, *buf_ + buf_.length());
CHECK_EQ(header_string.As<String>()->WriteOneByte(
isolate,
reinterpret_cast<uint8_t*>(header_contents),
0,
header_string_len,
String::NO_NULL_TERMINATION),
header_string_len);
size_t n = 0;
char* p;
for (p = header_contents; p < header_contents + header_string_len; n++) {
if (n >= count_) {
// This can happen if a passed header contained a null byte. In that
// case, just provide nghttp2 with an invalid header to make it reject
// the headers list.
static uint8_t zero = '\0';
nva[0].name = nva[0].value = &zero;
nva[0].namelen = nva[0].valuelen = 1;
count_ = 1;
return;
}
nva[n].flags = NGHTTP2_NV_FLAG_NONE;
nva[n].name = reinterpret_cast<uint8_t*>(p);
nva[n].namelen = strlen(p);
p += nva[n].namelen + 1;
nva[n].value = reinterpret_cast<uint8_t*>(p);
nva[n].valuelen = strlen(p);
p += nva[n].valuelen + 1;
}
}
Origins::Origins(Isolate* isolate,
Local<Context> context,
Local<String> origin_string,
size_t origin_count) : count_(origin_count) {
int origin_string_len = origin_string->Length();
if (count_ == 0) {
CHECK_EQ(origin_string_len, 0);
return;
}
// Allocate a single buffer with count_ nghttp2_nv structs, followed
// by the raw header data as passed from JS. This looks like:
// | possible padding | nghttp2_nv | nghttp2_nv | ... | header contents |
buf_.AllocateSufficientStorage((alignof(nghttp2_origin_entry) - 1) +
count_ * sizeof(nghttp2_origin_entry) +
origin_string_len);
// Make sure the start address is aligned appropriately for an nghttp2_nv*.
char* start = reinterpret_cast<char*>(
ROUND_UP(reinterpret_cast<uintptr_t>(*buf_),
alignof(nghttp2_origin_entry)));
char* origin_contents = start + (count_ * sizeof(nghttp2_origin_entry));
nghttp2_origin_entry* const nva =
reinterpret_cast<nghttp2_origin_entry*>(start);
CHECK_LE(origin_contents + origin_string_len, *buf_ + buf_.length());
CHECK_EQ(origin_string->WriteOneByte(
isolate,
reinterpret_cast<uint8_t*>(origin_contents),
0,
origin_string_len,
String::NO_NULL_TERMINATION),
origin_string_len);
size_t n = 0;
char* p;
for (p = origin_contents; p < origin_contents + origin_string_len; n++) {
if (n >= count_) {
static uint8_t zero = '\0';
nva[0].origin = &zero;
nva[0].origin_len = 1;
count_ = 1;
return;
}
nva[n].origin = reinterpret_cast<uint8_t*>(p);
nva[n].origin_len = strlen(p);
p += nva[n].origin_len + 1;
}
}
// Sets the various callback functions that nghttp2 will use to notify us
// about significant events while processing http2 stuff.
Http2Session::Callbacks::Callbacks(bool kHasGetPaddingCallback) {
CHECK_EQ(nghttp2_session_callbacks_new(&callbacks), 0);
nghttp2_session_callbacks_set_on_begin_headers_callback(
callbacks, OnBeginHeadersCallback);
nghttp2_session_callbacks_set_on_header_callback2(
callbacks, OnHeaderCallback);
nghttp2_session_callbacks_set_on_frame_recv_callback(
callbacks, OnFrameReceive);
nghttp2_session_callbacks_set_on_stream_close_callback(
callbacks, OnStreamClose);
nghttp2_session_callbacks_set_on_data_chunk_recv_callback(
callbacks, OnDataChunkReceived);
nghttp2_session_callbacks_set_on_frame_not_send_callback(
callbacks, OnFrameNotSent);
nghttp2_session_callbacks_set_on_invalid_header_callback2(
callbacks, OnInvalidHeader);
nghttp2_session_callbacks_set_error_callback(
callbacks, OnNghttpError);
nghttp2_session_callbacks_set_send_data_callback(
callbacks, OnSendData);
nghttp2_session_callbacks_set_on_invalid_frame_recv_callback(
callbacks, OnInvalidFrame);
nghttp2_session_callbacks_set_on_frame_send_callback(
callbacks, OnFrameSent);
if (kHasGetPaddingCallback) {
nghttp2_session_callbacks_set_select_padding_callback(
callbacks, OnSelectPadding);
}
}
Http2Session::Callbacks::~Callbacks() {
nghttp2_session_callbacks_del(callbacks);
}
// Track memory allocated by nghttp2 using a custom allocator.
class Http2Session::MemoryAllocatorInfo {
public:
explicit MemoryAllocatorInfo(Http2Session* session)
: info({ session, H2Malloc, H2Free, H2Calloc, H2Realloc }) {}
static void* H2Malloc(size_t size, void* user_data) {
return H2Realloc(nullptr, size, user_data);
}
static void* H2Calloc(size_t nmemb, size_t size, void* user_data) {
size_t real_size = MultiplyWithOverflowCheck(nmemb, size);
void* mem = H2Malloc(real_size, user_data);
if (mem != nullptr)
memset(mem, 0, real_size);
return mem;
}
static void H2Free(void* ptr, void* user_data) {
if (ptr == nullptr) return; // free(null); happens quite often.
void* result = H2Realloc(ptr, 0, user_data);
CHECK_EQ(result, nullptr);
}
static void* H2Realloc(void* ptr, size_t size, void* user_data) {
Http2Session* session = static_cast<Http2Session*>(user_data);
size_t previous_size = 0;
char* original_ptr = nullptr;
// We prepend each allocated buffer with a size_t containing the full
// size of the allocation.
if (size > 0) size += sizeof(size_t);
if (ptr != nullptr) {
// We are free()ing or re-allocating.
original_ptr = static_cast<char*>(ptr) - sizeof(size_t);
previous_size = *reinterpret_cast<size_t*>(original_ptr);
// This means we called StopTracking() on this pointer before.
if (previous_size == 0) {
// Fall back to the standard Realloc() function.
char* ret = UncheckedRealloc(original_ptr, size);
if (ret != nullptr)
ret += sizeof(size_t);
return ret;
}
}
CHECK_GE(session->current_nghttp2_memory_, previous_size);
// TODO(addaleax): Add the following, and handle NGHTTP2_ERR_NOMEM properly
// everywhere:
//
// if (size > previous_size &&
// !session->IsAvailableSessionMemory(size - previous_size)) {
// return nullptr;
//}
char* mem = UncheckedRealloc(original_ptr, size);
if (mem != nullptr) {
// Adjust the memory info counter.
session->current_nghttp2_memory_ += size - previous_size;
*reinterpret_cast<size_t*>(mem) = size;
mem += sizeof(size_t);
} else if (size == 0) {
session->current_nghttp2_memory_ -= previous_size;
}
return mem;
}
static void StopTracking(Http2Session* session, void* ptr) {
size_t* original_ptr = reinterpret_cast<size_t*>(
static_cast<char*>(ptr) - sizeof(size_t));
session->current_nghttp2_memory_ -= *original_ptr;
*original_ptr = 0;
}
inline nghttp2_mem* operator*() { return &info; }
nghttp2_mem info;
};
void Http2Session::StopTrackingRcbuf(nghttp2_rcbuf* buf) {
MemoryAllocatorInfo::StopTracking(this, buf);
}
Http2Session::Http2Session(Environment* env,
Local<Object> wrap,
nghttp2_session_type type)
: AsyncWrap(env, wrap, AsyncWrap::PROVIDER_HTTP2SESSION),
session_type_(type) {
MakeWeak();
statistics_.start_time = uv_hrtime();
// Capture the configuration options for this session
Http2Options opts(env, type);
max_session_memory_ = opts.GetMaxSessionMemory();
uint32_t maxHeaderPairs = opts.GetMaxHeaderPairs();
max_header_pairs_ =
type == NGHTTP2_SESSION_SERVER
? std::max(maxHeaderPairs, 4U) // minimum # of request headers
: std::max(maxHeaderPairs, 1U); // minimum # of response headers
max_outstanding_pings_ = opts.GetMaxOutstandingPings();
max_outstanding_settings_ = opts.GetMaxOutstandingSettings();
padding_strategy_ = opts.GetPaddingStrategy();
bool hasGetPaddingCallback =
padding_strategy_ != PADDING_STRATEGY_NONE;
nghttp2_session_callbacks* callbacks
= callback_struct_saved[hasGetPaddingCallback ? 1 : 0].callbacks;
auto fn = type == NGHTTP2_SESSION_SERVER ?
nghttp2_session_server_new3 :
nghttp2_session_client_new3;
MemoryAllocatorInfo allocator_info(this);
// This should fail only if the system is out of memory, which
// is going to cause lots of other problems anyway, or if any
// of the options are out of acceptable range, which we should
// be catching before it gets this far. Either way, crash if this
// fails.
CHECK_EQ(fn(&session_, callbacks, this, *opts, *allocator_info), 0);
outgoing_storage_.reserve(4096);
outgoing_buffers_.reserve(32);
}
Http2Session::~Http2Session() {
CHECK_EQ(flags_ & SESSION_STATE_HAS_SCOPE, 0);
Debug(this, "freeing nghttp2 session");
for (const auto& iter : streams_)
iter.second->session_ = nullptr;
nghttp2_session_del(session_);
CHECK_EQ(current_nghttp2_memory_, 0);
}
std::string Http2Session::diagnostic_name() const {
return std::string("Http2Session ") + TypeName() + " (" +
std::to_string(static_cast<int64_t>(get_async_id())) + ")";
}
inline bool HasHttp2Observer(Environment* env) {
AliasedBuffer<uint32_t, Uint32Array>& observers =
env->performance_state()->observers;
return observers[performance::NODE_PERFORMANCE_ENTRY_TYPE_HTTP2] != 0;
}
void Http2Stream::EmitStatistics() {
if (!HasHttp2Observer(env()))
return;
Http2StreamPerformanceEntry* entry =
new Http2StreamPerformanceEntry(env(), id_, statistics_);
env()->SetImmediate([](Environment* env, void* data) {
// This takes ownership, the entry is destroyed at the end of this scope.
std::unique_ptr<Http2StreamPerformanceEntry> entry {
static_cast<Http2StreamPerformanceEntry*>(data) };
if (!HasHttp2Observer(env))
return;
HandleScope handle_scope(env->isolate());
AliasedBuffer<double, Float64Array>& buffer =
env->http2_state()->stream_stats_buffer;
buffer[IDX_STREAM_STATS_ID] = entry->id();
if (entry->first_byte() != 0) {
buffer[IDX_STREAM_STATS_TIMETOFIRSTBYTE] =
(entry->first_byte() - entry->startTimeNano()) / 1e6;
} else {
buffer[IDX_STREAM_STATS_TIMETOFIRSTBYTE] = 0;
}
if (entry->first_header() != 0) {
buffer[IDX_STREAM_STATS_TIMETOFIRSTHEADER] =
(entry->first_header() - entry->startTimeNano()) / 1e6;
} else {
buffer[IDX_STREAM_STATS_TIMETOFIRSTHEADER] = 0;
}
if (entry->first_byte_sent() != 0) {
buffer[IDX_STREAM_STATS_TIMETOFIRSTBYTESENT] =
(entry->first_byte_sent() - entry->startTimeNano()) / 1e6;
} else {
buffer[IDX_STREAM_STATS_TIMETOFIRSTBYTESENT] = 0;
}
buffer[IDX_STREAM_STATS_SENTBYTES] = entry->sent_bytes();
buffer[IDX_STREAM_STATS_RECEIVEDBYTES] = entry->received_bytes();
entry->Notify(entry->ToObject());
}, static_cast<void*>(entry));
}
void Http2Session::EmitStatistics() {
if (!HasHttp2Observer(env()))
return;
Http2SessionPerformanceEntry* entry =
new Http2SessionPerformanceEntry(env(), statistics_, session_type_);
env()->SetImmediate([](Environment* env, void* data) {
// This takes ownership, the entr is destroyed at the end of this scope.
std::unique_ptr<Http2SessionPerformanceEntry> entry {
static_cast<Http2SessionPerformanceEntry*>(data) };
if (!HasHttp2Observer(env))
return;
HandleScope handle_scope(env->isolate());
AliasedBuffer<double, Float64Array>& buffer =
env->http2_state()->session_stats_buffer;
buffer[IDX_SESSION_STATS_TYPE] = entry->type();
buffer[IDX_SESSION_STATS_PINGRTT] = entry->ping_rtt() / 1e6;
buffer[IDX_SESSION_STATS_FRAMESRECEIVED] = entry->frame_count();
buffer[IDX_SESSION_STATS_FRAMESSENT] = entry->frame_sent();
buffer[IDX_SESSION_STATS_STREAMCOUNT] = entry->stream_count();
buffer[IDX_SESSION_STATS_STREAMAVERAGEDURATION] =
entry->stream_average_duration();
buffer[IDX_SESSION_STATS_DATA_SENT] = entry->data_sent();
buffer[IDX_SESSION_STATS_DATA_RECEIVED] = entry->data_received();
buffer[IDX_SESSION_STATS_MAX_CONCURRENT_STREAMS] =
entry->max_concurrent_streams();
entry->Notify(entry->ToObject());
}, static_cast<void*>(entry));
}
// Closes the session and frees the associated resources
void Http2Session::Close(uint32_t code, bool socket_closed) {
Debug(this, "closing session");
if (flags_ & SESSION_STATE_CLOSING)
return;
flags_ |= SESSION_STATE_CLOSING;
// Stop reading on the i/o stream
if (stream_ != nullptr)
stream_->ReadStop();
// If the socket is not closed, then attempt to send a closing GOAWAY
// frame. There is no guarantee that this GOAWAY will be received by
// the peer but the HTTP/2 spec recommends sending it anyway. We'll
// make a best effort.
if (!socket_closed) {
Debug(this, "terminating session with code %d", code);
CHECK_EQ(nghttp2_session_terminate_session(session_, code), 0);
SendPendingData();
} else if (stream_ != nullptr) {
stream_->RemoveStreamListener(this);
}
flags_ |= SESSION_STATE_CLOSED;
// If there are outstanding pings, those will need to be canceled, do
// so on the next iteration of the event loop to avoid calling out into
// javascript since this may be called during garbage collection.
while (!outstanding_pings_.empty()) {
Http2Session::Http2Ping* ping = PopPing();
env()->SetImmediate([](Environment* env, void* data) {
static_cast<Http2Session::Http2Ping*>(data)->Done(false);
}, static_cast<void*>(ping));
}
statistics_.end_time = uv_hrtime();
EmitStatistics();
}
// Locates an existing known stream by ID. nghttp2 has a similar method
// but this is faster and does not fail if the stream is not found.
inline Http2Stream* Http2Session::FindStream(int32_t id) {
auto s = streams_.find(id);
return s != streams_.end() ? s->second : nullptr;
}
inline bool Http2Session::CanAddStream() {
uint32_t maxConcurrentStreams =
nghttp2_session_get_local_settings(
session_, NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS);
size_t maxSize =
std::min(streams_.max_size(), static_cast<size_t>(maxConcurrentStreams));
// We can add a new stream so long as we are less than the current
// maximum on concurrent streams and there's enough available memory
return streams_.size() < maxSize &&
IsAvailableSessionMemory(sizeof(Http2Stream));
}
inline void Http2Session::AddStream(Http2Stream* stream) {
CHECK_GE(++statistics_.stream_count, 0);
streams_[stream->id()] = stream;
size_t size = streams_.size();
if (size > statistics_.max_concurrent_streams)
statistics_.max_concurrent_streams = size;
IncrementCurrentSessionMemory(sizeof(*stream));
}
inline void Http2Session::RemoveStream(Http2Stream* stream) {
if (streams_.empty() || stream == nullptr)
return; // Nothing to remove, item was never added?
streams_.erase(stream->id());
DecrementCurrentSessionMemory(sizeof(*stream));
}
// Used as one of the Padding Strategy functions. Will attempt to ensure
// that the total frame size, including header bytes, are 8-byte aligned.
// If maxPayloadLen is smaller than the number of bytes necessary to align,
// will return maxPayloadLen instead.
ssize_t Http2Session::OnDWordAlignedPadding(size_t frameLen,
size_t maxPayloadLen) {
size_t r = (frameLen + 9) % 8;
if (r == 0) return frameLen; // If already a multiple of 8, return.
size_t pad = frameLen + (8 - r);
// If maxPayloadLen happens to be less than the calculated pad length,
// use the max instead, even tho this means the frame will not be
// aligned.
pad = std::min(maxPayloadLen, pad);
Debug(this, "using frame size padding: %d", pad);
return pad;
}
// Used as one of the Padding Strategy functions. Uses the maximum amount
// of padding allowed for the current frame.
ssize_t Http2Session::OnMaxFrameSizePadding(size_t frameLen,
size_t maxPayloadLen) {
Debug(this, "using max frame size padding: %d", maxPayloadLen);
return maxPayloadLen;
}
// Used as one of the Padding Strategy functions. Uses a callback to JS land
// to determine the amount of padding for the current frame. This option is
// rather more expensive because of the JS boundary cross. It generally should
// not be the preferred option.
ssize_t Http2Session::OnCallbackPadding(size_t frameLen,
size_t maxPayloadLen) {
if (frameLen == 0) return 0;
Debug(this, "using callback to determine padding");
Isolate* isolate = env()->isolate();
HandleScope handle_scope(isolate);
Local<Context> context = env()->context();
Context::Scope context_scope(context);
AliasedBuffer<uint32_t, Uint32Array>& buffer =
env()->http2_state()->padding_buffer;
buffer[PADDING_BUF_FRAME_LENGTH] = frameLen;
buffer[PADDING_BUF_MAX_PAYLOAD_LENGTH] = maxPayloadLen;
buffer[PADDING_BUF_RETURN_VALUE] = frameLen;
MakeCallback(env()->ongetpadding_string(), 0, nullptr);
uint32_t retval = buffer[PADDING_BUF_RETURN_VALUE];
retval = std::min(retval, static_cast<uint32_t>(maxPayloadLen));
retval = std::max(retval, static_cast<uint32_t>(frameLen));
Debug(this, "using padding size %d", retval);
return retval;
}
// Write data received from the i/o stream to the underlying nghttp2_session.
// On each call to nghttp2_session_mem_recv, nghttp2 will begin calling the
// various callback functions. Each of these will typically result in a call
// out to JavaScript so this particular function is rather hot and can be
// quite expensive. This is a potential performance optimization target later.
ssize_t Http2Session::Write(const uv_buf_t* bufs, size_t nbufs) {
size_t total = 0;
// Note that nghttp2_session_mem_recv is a synchronous operation that
// will trigger a number of other callbacks. Those will, in turn have
// multiple side effects.
for (size_t n = 0; n < nbufs; n++) {
Debug(this, "receiving %d bytes [wants data? %d]",
bufs[n].len,
nghttp2_session_want_read(session_));
ssize_t ret =
nghttp2_session_mem_recv(session_,
reinterpret_cast<uint8_t*>(bufs[n].base),
bufs[n].len);
CHECK_NE(ret, NGHTTP2_ERR_NOMEM);
if (ret < 0)
return ret;
total += ret;
}
// Send any data that was queued up while processing the received data.
if (!IsDestroyed()) {
SendPendingData();
}
return total;
}
inline int32_t GetFrameID(const nghttp2_frame* frame) {
// If this is a push promise, we want to grab the id of the promised stream
return (frame->hd.type == NGHTTP2_PUSH_PROMISE) ?
frame->push_promise.promised_stream_id :
frame->hd.stream_id;
}
// Called by nghttp2 at the start of receiving a HEADERS frame. We use this
// callback to determine if a new stream is being created or if we are simply
// adding a new block of headers to an existing stream. The header pairs
// themselves are set in the OnHeaderCallback
int Http2Session::OnBeginHeadersCallback(nghttp2_session* handle,
const nghttp2_frame* frame,
void* user_data) {
Http2Session* session = static_cast<Http2Session*>(user_data);
int32_t id = GetFrameID(frame);
Debug(session, "beginning headers for stream %d", id);
Http2Stream* stream = session->FindStream(id);
if (stream == nullptr) {
if (!session->CanAddStream()) {
// Too many concurrent streams being opened
nghttp2_submit_rst_stream(**session, NGHTTP2_FLAG_NONE, id,
NGHTTP2_ENHANCE_YOUR_CALM);
return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE;
}
new Http2Stream(session, id, frame->headers.cat);
} else if (!stream->IsDestroyed()) {
stream->StartHeaders(frame->headers.cat);
}
return 0;
}
// Called by nghttp2 for each header name/value pair in a HEADERS block.
// This had to have been preceded by a call to OnBeginHeadersCallback so
// the Http2Stream is guaranteed to already exist.
int Http2Session::OnHeaderCallback(nghttp2_session* handle,
const nghttp2_frame* frame,
nghttp2_rcbuf* name,
nghttp2_rcbuf* value,
uint8_t flags,
void* user_data) {
Http2Session* session = static_cast<Http2Session*>(user_data);
int32_t id = GetFrameID(frame);
Http2Stream* stream = session->FindStream(id);
// If stream is null at this point, either something odd has happened
// or the stream was closed locally while header processing was occurring.
// either way, do not proceed and close the stream.
if (stream == nullptr)
return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE;
// If the stream has already been destroyed, ignore.
if (!stream->IsDestroyed() && !stream->AddHeader(name, value, flags)) {
// This will only happen if the connected peer sends us more
// than the allowed number of header items at any given time
stream->SubmitRstStream(NGHTTP2_ENHANCE_YOUR_CALM);
return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE;
}
return 0;
}
// Called by nghttp2 when a complete HTTP2 frame has been received. There are
// only a handful of frame types tha we care about handling here.
int Http2Session::OnFrameReceive(nghttp2_session* handle,
const nghttp2_frame* frame,
void* user_data) {
Http2Session* session = static_cast<Http2Session*>(user_data);
session->statistics_.frame_count++;
Debug(session, "complete frame received: type: %d",
frame->hd.type);
switch (frame->hd.type) {
case NGHTTP2_DATA:
session->HandleDataFrame(frame);
break;
case NGHTTP2_PUSH_PROMISE:
// Intentional fall-through, handled just like headers frames
case NGHTTP2_HEADERS:
session->HandleHeadersFrame(frame);
break;
case NGHTTP2_SETTINGS:
session->HandleSettingsFrame(frame);
break;
case NGHTTP2_PRIORITY:
session->HandlePriorityFrame(frame);
break;
case NGHTTP2_GOAWAY:
session->HandleGoawayFrame(frame);
break;
case NGHTTP2_PING:
session->HandlePingFrame(frame);
break;
case NGHTTP2_ALTSVC:
session->HandleAltSvcFrame(frame);
break;
case NGHTTP2_ORIGIN:
session->HandleOriginFrame(frame);
break;
default:
break;
}
return 0;
}
int Http2Session::OnInvalidFrame(nghttp2_session* handle,
const nghttp2_frame* frame,