public:

static void DisconnectAndDispose(TcpHolder* holder);

using Pointer = DeleteFnPtr<TcpHolder, DisconnectAndDispose>;

static Pointer Accept(uv_stream_t* server,

InspectorSocket::DelegatePointer delegate);

void SetHandler(ProtocolHandler* handler);

int WriteRaw(const std::vector<char>& buffer, uv_write_cb write_cb);

uv_tcp_t* tcp() {

return &tcp_;

}

InspectorSocket::Delegate* delegate();

private:

static TcpHolder* From(void* handle) {

return node::ContainerOf(&TcpHolder::tcp_,

reinterpret_cast<uv_tcp_t*>(handle));

}

static void OnClosed(uv_handle_t* handle);

static void OnDataReceivedCb(uv_stream_t* stream, ssize_t nread,

const uv_buf_t* buf);

explicit TcpHolder(InspectorSocket::DelegatePointer delegate);

~TcpHolder() = default;

void ReclaimUvBuf(const uv_buf_t* buf, ssize_t read);

uv_tcp_t tcp_;

const InspectorSocket::DelegatePointer delegate_;

ProtocolHandler* handler_;

std::vector<char> buffer;

public:

ProtocolHandler(InspectorSocket* inspector, TcpHolder::Pointer tcp);

virtual void AcceptUpgrade(const std::string& accept_key) = 0;

virtual void OnData(std::vector<char>* data) = 0;

virtual void OnEof() = 0;

virtual void Write(const std::vector<char> data) = 0;

virtual void CancelHandshake() = 0;

std::string GetHost() const;

InspectorSocket* inspector() {

return inspector_;

}

virtual void Shutdown() = 0;

protected:

virtual ~ProtocolHandler() = default;

int WriteRaw(const std::vector<char>& buffer, uv_write_cb write_cb);

InspectorSocket::Delegate* delegate();

InspectorSocket* const inspector_;

TcpHolder::Pointer tcp_;

const char* ptr = buf;

const char* end = ptr + len;

const char* cptr;

char c;

int i;

while (ptr < end) {

cptr = ptr;

for (i = 0; i < 16 && ptr < end; i++) {

printf("%2.2X ", static_cast<unsigned char>(*(ptr++)));

}

for (i = 72 - (i * 4); i > 0; i--) {

printf(" ");

}

for (i = 0; i < 16 && cptr < end; i++) {

c = *(cptr++);

printf("%c", (c > 0x19) ? c : '.');

}

printf("\n");

}

printf("\n\n");

public:

WriteRequest(ProtocolHandler* handler, const std::vector<char>& buffer)

: handler(handler)

, storage(buffer)

, req(uv_write_t())

, buf(uv_buf_init(storage.data(), storage.size())) {}

static WriteRequest* from_write_req(uv_write_t* req) {

return node::ContainerOf(&WriteRequest::req, req);

}

static void Cleanup(uv_write_t* req, int status) {

delete WriteRequest::from_write_req(req);

}

ProtocolHandler* const handler;

std::vector<char> storage;

uv_write_t req;

uv_buf_t buf;

char (*buffer)[ACCEPT_KEY_LENGTH]) {

// Magic string from websockets spec.

static const char ws_magic[] = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";

std::string input(client_key + ws_magic);

char hash[SHA_DIGEST_LENGTH];

CHECK(ACCEPT_KEY_LENGTH >= nbytes::Base64EncodedSize(SHA_DIGEST_LENGTH) &&

"not enough space provided for base64 encode");

USE(SHA1(reinterpret_cast<const unsigned char*>(input.data()),

input.size(),

reinterpret_cast<unsigned char*>(hash)));

simdutf::binary_to_base64(hash, sizeof(hash), *buffer);

size_t last_colon_pos = host.rfind(':');

if (last_colon_pos == std::string::npos)

return host;

size_t bracket = host.rfind(']');

if (bracket == std::string::npos || last_colon_pos > bracket)

return host.substr(0, last_colon_pos);

return host;

// To avoid DNS rebinding attacks, we are aware of the following requirements:

// * the host name must be an IP address (CVE-2018-7160, CVE-2022-32212),

// * the IP address must be routable (hackerone.com/reports/1632921), and

// * the IP address must be formatted unambiguously (CVE-2022-43548).

// The logic below assumes that the string is null-terminated, so ensure that

// we did not somehow end up with null characters within the string.

if (host.find('\0') != std::string::npos) return false;

// All IPv6 addresses must be enclosed in square brackets, and anything

// enclosed in square brackets must be an IPv6 address.

if (host.length() >= 4 && host.front() == '[' && host.back() == ']') {

// INET6_ADDRSTRLEN is the maximum length of the dual format (including the

// terminating null character), which is the longest possible representation

// of an IPv6 address: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:ddd.ddd.ddd.ddd

if (host.length() - 2 >= INET6_ADDRSTRLEN) return false;

// Annoyingly, libuv's implementation of inet_pton() deviates from other

// implementations of the function in that it allows '%' in IPv6 addresses.

if (host.find('%') != std::string::npos) return false;

// Parse the IPv6 address to ensure it is syntactically valid.

char ipv6_str[INET6_ADDRSTRLEN];

std::copy(host.begin() + 1, host.end() - 1, ipv6_str);

ipv6_str[host.length() - 2] = '\0';

unsigned char ipv6[sizeof(struct in6_addr)];

if (uv_inet_pton(AF_INET6, ipv6_str, ipv6) != 0) return false;

// The only non-routable IPv6 address is ::/128. It should not be necessary

// to explicitly reject it because it will still be enclosed in square

// brackets and not even macOS should make DNS requests in that case, but

// history has taught us that we cannot be careful enough.

// Note that RFC 4291 defines both "IPv4-Compatible IPv6 Addresses" and

// "IPv4-Mapped IPv6 Addresses", which means that there are IPv6 addresses

// (other than ::/128) that represent non-routable IPv4 addresses. However,

// this translation assumes that the host is interpreted as an IPv6 address

// in the first place, at which point DNS rebinding should not be an issue.

if (std::ranges::all_of(ipv6, [](auto b) { return b == 0; })) {

return false;

}

// It is a syntactically valid and routable IPv6 address enclosed in square

// brackets. No client should be able to misinterpret this.

return true;

}

// Anything not enclosed in square brackets must be an IPv4 address. It is

// important here that inet_pton() accepts only the so-called dotted-decimal

// notation, which is a strict subset of the so-called numbers-and-dots

// notation that is allowed by inet_aton() and inet_addr(). This subset does

// not allow hexadecimal or octal number formats.

unsigned char ipv4[sizeof(struct in_addr)];

if (uv_inet_pton(AF_INET, host.c_str(), ipv4) != 0) return false;

// The only strictly non-routable IPv4 address is 0.0.0.0, and macOS will make

// DNS requests for this IP address, so we need to explicitly reject it. In

// fact, we can safely reject all of 0.0.0.0/8 (see Section 3.2 of RFC 791 and

// Section 3.2.1.3 of RFC 1122).

// Note that inet_pton() stores the IPv4 address in network byte order.

if (ipv4[0] == 0) return false;

// It is a routable IPv4 address in dotted-decimal notation.

return true;

std::vector<char> frame;

OpCode op_code = kOpCodeText;

frame.push_back(kFinalBit | op_code);

const size_t data_length = message.size();

if (data_length <= kMaxSingleBytePayloadLength) {

frame.push_back(static_cast<char>(data_length));

} else if (data_length <= 0xFFFF) {

frame.push_back(kTwoBytePayloadLengthField);

frame.push_back((data_length & 0xFF00) >> 8);

frame.push_back(data_length & 0xFF);

} else {

frame.push_back(kEightBytePayloadLengthField);

char extended_payload_length[8];

size_t remaining = data_length;

// Fill the length into extended_payload_length in the network byte order.

for (int i = 0; i < 8; ++i) {

extended_payload_length[7 - i] = remaining & 0xFF;

remaining >>= 8;

}

frame.insert(frame.end(), extended_payload_length,

extended_payload_length + 8);

CHECK_EQ(0, remaining);

}

frame.insert(frame.end(), message.begin(), message.end());

return frame;

bool client_frame,

int* bytes_consumed,

std::vector<char>* output,

bool* compressed) {

*bytes_consumed = 0;

if (buffer.size() < 2)

return FRAME_INCOMPLETE;

auto it = buffer.begin();

unsigned char first_byte = *it++;

unsigned char second_byte = *it++;

bool final = (first_byte & kFinalBit) != 0;

bool reserved1 = (first_byte & kReserved1Bit) != 0;

bool reserved2 = (first_byte & kReserved2Bit) != 0;

bool reserved3 = (first_byte & kReserved3Bit) != 0;

int op_code = first_byte & kOpCodeMask;

bool masked = (second_byte & kMaskBit) != 0;

*compressed = reserved1;

if (!final || reserved2 || reserved3)

return FRAME_ERROR; // Only compression extension is supported.

bool closed = false;

switch (op_code) {

case kOpCodeClose:

closed = true;

break;

case kOpCodeText:

break;

case kOpCodeBinary: // We don't support binary frames yet.

case kOpCodeContinuation: // We don't support binary frames yet.

case kOpCodePing: // We don't support binary frames yet.

case kOpCodePong: // We don't support binary frames yet.

default:

return FRAME_ERROR;

}

// In Hybi-17 spec client MUST mask its frame.

if (client_frame && !masked) {

return FRAME_ERROR;

}

uint64_t payload_length64 = second_byte & kPayloadLengthMask;

if (payload_length64 > kMaxSingleBytePayloadLength) {

int extended_payload_length_size;

if (payload_length64 == kTwoBytePayloadLengthField) {

extended_payload_length_size = 2;

} else if (payload_length64 == kEightBytePayloadLengthField) {

extended_payload_length_size = 8;

} else {

return FRAME_ERROR;

}

if ((buffer.end() - it) < extended_payload_length_size)

return FRAME_INCOMPLETE;

payload_length64 = 0;

for (int i = 0; i < extended_payload_length_size; ++i) {

payload_length64 <<= 8;

payload_length64 |= static_cast<unsigned char>(*it++);

}

}

static const uint64_t max_payload_length = 0x7FFFFFFFFFFFFFFFull;

static const size_t max_length = SIZE_MAX;

if (payload_length64 > max_payload_length ||

payload_length64 > max_length - kMaskingKeyWidthInBytes) {

// WebSocket frame length too large.

return FRAME_ERROR;

}

size_t payload_length = static_cast<size_t>(payload_length64);

if (buffer.size() - kMaskingKeyWidthInBytes < payload_length)

return FRAME_INCOMPLETE;

std::vector<char>::const_iterator masking_key = it;

std::vector<char>::const_iterator payload = it + kMaskingKeyWidthInBytes;

for (size_t i = 0; i < payload_length; ++i) // Unmask the payload.

output->insert(output->end(),

payload[i] ^ masking_key[i % kMaskingKeyWidthInBytes]);

size_t pos = it + kMaskingKeyWidthInBytes + payload_length - buffer.begin();

*bytes_consumed = pos;

return closed ? FRAME_CLOSE : FRAME_OK;

public:

WsHandler(InspectorSocket* inspector, TcpHolder::Pointer tcp)

: ProtocolHandler(inspector, std::move(tcp)),

OnCloseSent(&WsHandler::WaitForCloseReply),

OnCloseReceived(&WsHandler::CloseFrameReceived),

dispose_(false) { }

void AcceptUpgrade(const std::string& accept_key) override { }

void CancelHandshake() override {}

void OnEof() override {

tcp_.reset();

if (dispose_)

delete this;

}

void OnData(std::vector<char>* data) override {

// 1. Parse.

int processed = 0;

do {

processed = ParseWsFrames(*data);

// 2. Fix the data size & length

if (processed > 0) {

remove_from_beginning(data, processed);

}

} while (processed > 0 && !data->empty());

}

void Write(const std::vector<char> data) override {

std::vector<char> output = encode_frame_hybi17(data);

WriteRaw(output, WriteRequest::Cleanup);

}

protected:

void Shutdown() override {

if (tcp_) {

dispose_ = true;

SendClose();

} else {

delete this;

}

}

private:

using Callback = void (WsHandler::*)();

static void OnCloseFrameWritten(uv_write_t* req, int status) {

WriteRequest* wr = WriteRequest::from_write_req(req);

WsHandler* handler = static_cast<WsHandler*>(wr->handler);

delete wr;

Callback cb = handler->OnCloseSent;

(handler->*cb)();

}

void WaitForCloseReply() {

OnCloseReceived = &WsHandler::OnEof;

}

void SendClose() {

WriteRaw(std::vector<char>(CLOSE_FRAME, CLOSE_FRAME + sizeof(CLOSE_FRAME)),

OnCloseFrameWritten);

}

void CloseFrameReceived() {

OnCloseSent = &WsHandler::OnEof;

SendClose();

}

int ParseWsFrames(const std::vector<char>& buffer) {

int bytes_consumed = 0;

std::vector<char> output;

bool compressed = false;

ws_decode_result r = decode_frame_hybi17(buffer,

true /* client_frame */,

&bytes_consumed, &output,

&compressed);

// Compressed frame means client is ignoring the headers and misbehaves

if (compressed || r == FRAME_ERROR) {

OnEof();

bytes_consumed = 0;

} else if (r == FRAME_CLOSE) {

(this->*OnCloseReceived)();

bytes_consumed = 0;

} else if (r == FRAME_OK) {

delegate()->OnWsFrame(output);

}

return bytes_consumed;

}

Callback OnCloseSent;

Callback OnCloseReceived;

bool dispose_;

public:

HttpEvent(const std::string& path, bool upgrade, bool isGET,

const std::string& ws_key, const std::string& host)

: path(path), upgrade(upgrade), isGET(isGET), ws_key(ws_key),

host(host) { }

std::string path;

bool upgrade;

bool isGET;

std::string ws_key;

std::string host;

public:

explicit HttpHandler(InspectorSocket* inspector, TcpHolder::Pointer tcp)

: ProtocolHandler(inspector, std::move(tcp)),

parsing_value_(false) {

llhttp_init(&parser_, HTTP_REQUEST, &parser_settings);

llhttp_settings_init(&parser_settings);

parser_settings.on_header_field = OnHeaderField;

parser_settings.on_header_value = OnHeaderValue;

parser_settings.on_message_complete = OnMessageComplete;

parser_settings.on_url = OnPath;

}

void AcceptUpgrade(const std::string& accept_key) override {

char accept_string[ACCEPT_KEY_LENGTH];

generate_accept_string(accept_key, &accept_string);

const char accept_ws_prefix[] = "HTTP/1.1 101 Switching Protocols\r\n"

"Upgrade: websocket\r\n"

"Connection: Upgrade\r\n"

"Sec-WebSocket-Accept: ";

const char accept_ws_suffix[] = "\r\n\r\n";

std::vector<char> reply(accept_ws_prefix,

accept_ws_prefix + sizeof(accept_ws_prefix) - 1);

reply.insert(reply.end(), accept_string,

accept_string + sizeof(accept_string));

reply.insert(reply.end(), accept_ws_suffix,

accept_ws_suffix + sizeof(accept_ws_suffix) - 1);

if (WriteRaw(reply, WriteRequest::Cleanup) >= 0) {

inspector_->SwitchProtocol(new WsHandler(inspector_, std::move(tcp_)));

} else {

tcp_.reset();

}

}

void CancelHandshake() override {

const char HANDSHAKE_FAILED_RESPONSE[] =

"HTTP/1.0 400 Bad Request\r\n"

"Content-Type: text/html; charset=UTF-8\r\n\r\n"

"WebSockets request was expected\r\n";

WriteRaw(std::vector<char>(HANDSHAKE_FAILED_RESPONSE,

HANDSHAKE_FAILED_RESPONSE + sizeof(HANDSHAKE_FAILED_RESPONSE) - 1),

ThenCloseAndReportFailure);

}

void OnEof() override {

tcp_.reset();

}

void OnData(std::vector<char>* data) override {

llhttp_errno_t err;

err = llhttp_execute(&parser_, data->data(), data->size());

if (err == HPE_PAUSED_UPGRADE) {

err = HPE_OK;

llhttp_resume_after_upgrade(&parser_);

}

data->clear();

if (err != HPE_OK) {

CancelHandshake();

}

// Event handling may delete *this

std::vector<HttpEvent> events;

std::swap(events, events_);

for (const HttpEvent& event : events) {

if (!IsAllowedHost(event.host) || !event.isGET) {

CancelHandshake();

return;

} else if (!event.upgrade) {

delegate()->OnHttpGet(event.host, event.path);

} else if (event.ws_key.empty()) {

CancelHandshake();

return;

} else {

delegate()->OnSocketUpgrade(event.host, event.path, event.ws_key);

}

}

}

void Write(const std::vector<char> data) override {

WriteRaw(data, WriteRequest::Cleanup);

}

protected:

void Shutdown() override {

delete this;

}

private:

static void ThenCloseAndReportFailure(uv_write_t* req, int status) {

ProtocolHandler* handler = WriteRequest::from_write_req(req)->handler;

WriteRequest::Cleanup(req, status);

handler->inspector()->SwitchProtocol(nullptr);

}

static int OnHeaderValue(llhttp_t* parser, const char* at, size_t length) {

HttpHandler* handler = From(parser);

handler->parsing_value_ = true;

handler->headers_[handler->current_header_].append(at, length);

return 0;

}

static int OnHeaderField(llhttp_t* parser, const char* at, size_t length) {

HttpHandler* handler = From(parser);

if (handler->parsing_value_) {

handler->parsing_value_ = false;

handler->current_header_.clear();

}

handler->current_header_.append(at, length);

return 0;

}

static int OnPath(llhttp_t* parser, const char* at, size_t length) {

HttpHandler* handler = From(parser);

handler->path_.append(at, length);

return 0;

}

static HttpHandler* From(llhttp_t* parser) {

return node::ContainerOf(&HttpHandler::parser_, parser);

}

static int OnMessageComplete(llhttp_t* parser) {

// Event needs to be fired after the parser is done.

HttpHandler* handler = From(parser);

handler->events_.emplace_back(handler->path_,

parser->upgrade,

parser->method == HTTP_GET,

handler->HeaderValue("Sec-WebSocket-Key"),

handler->HeaderValue("Host"));

handler->path_ = "";

handler->parsing_value_ = false;

handler->headers_.clear();

handler->current_header_ = "";

return 0;

}

std::string HeaderValue(const std::string& header) const {

bool header_found = false;

std::string value;

for (const auto& header_value : headers_) {

if (node::StringEqualNoCaseN(header_value.first.data(), header.data(),

header.length())) {

if (header_found)

return "";

value = header_value.second;

header_found = true;

}

}

return value;

}

bool IsAllowedHost(const std::string& host_with_port) const {

std::string host = TrimPort(host_with_port);

return host.empty() || IsIPAddress(host)

|| node::StringEqualNoCase(host.data(), "localhost");

}

bool parsing_value_;

llhttp_t parser_;

llhttp_settings_t parser_settings;

std::vector<HttpEvent> events_;

std::string current_header_;

std::map<std::string, std::string> headers_;

std::string path_;

TcpHolder::Pointer tcp)

: inspector_(inspector), tcp_(std::move(tcp)) {

CHECK_NOT_NULL(tcp_);

tcp_->SetHandler(this);

char ip[INET6_ADDRSTRLEN];

sockaddr_storage addr;

int len = sizeof(addr);

int err = uv_tcp_getsockname(tcp_->tcp(),

reinterpret_cast<struct sockaddr*>(&addr),

&len);

if (err != 0)

return "";

if (addr.ss_family == AF_INET6) {

const sockaddr_in6* v6 = reinterpret_cast<const sockaddr_in6*>(&addr);

err = uv_ip6_name(v6, ip, sizeof(ip));

} else {

const sockaddr_in* v4 = reinterpret_cast<const sockaddr_in*>(&addr);

err = uv_ip4_name(v4, ip, sizeof(ip));

}

if (err != 0)

return "";

return ip;

uv_stream_t* server,

InspectorSocket::DelegatePointer delegate) {

TcpHolder* result = new TcpHolder(std::move(delegate));

uv_stream_t* tcp = reinterpret_cast<uv_stream_t*>(&result->tcp_);

int err = uv_tcp_init(server->loop, &result->tcp_);

if (err == 0) {

err = uv_accept(server, tcp);

}

if (err == 0) {

err = uv_read_start(tcp, allocate_buffer, OnDataReceivedCb);

}

if (err == 0) {

return TcpHolder::Pointer(result);

} else {

delete result;

return nullptr;

}

#if DUMP_WRITES

printf("%s (%ld bytes):\n", __FUNCTION__, buffer.size());

dump_hex(buffer.data(), buffer.size());

printf("\n");

#endif

// Freed in write_request_cleanup

WriteRequest* wr = new WriteRequest(handler_, buffer);

uv_stream_t* stream = reinterpret_cast<uv_stream_t*>(&tcp_);

int err = uv_write(&wr->req, stream, &wr->buf, 1, write_cb);

if (err < 0)

delete wr;

return err < 0;

const uv_buf_t* buf) {

#if DUMP_READS

if (nread >= 0) {

printf("%s (%ld bytes)\n", __FUNCTION__, nread);

dump_hex(buf->base, nread);

} else {

printf("[%s:%d] %s\n", __FUNCTION__, __LINE__, uv_err_name(nread));

}

#endif

TcpHolder* holder = From(tcp);

holder->ReclaimUvBuf(buf, nread);

if (nread < 0 || nread == UV_EOF) {

holder->handler_->OnEof();

} else {

holder->handler_->OnData(&holder->buffer);

}

if (read > 0) {

buffer.insert(buffer.end(), buf->base, buf->base + read);

}

delete[] buf->base;

DelegatePointer delegate) {

auto tcp = TcpHolder::Accept(server, std::move(delegate));

if (tcp) {

InspectorSocket* inspector = new InspectorSocket();

inspector->SwitchProtocol(new HttpHandler(inspector, std::move(tcp)));

return InspectorSocket::Pointer(inspector);

} else {

return InspectorSocket::Pointer(nullptr);

}