Add server implementation and tunnel padding

src/net/tools/naive/http_proxy_socket.cc

@@ -0,0 +1,327 @@
+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Copyright 2018 klzgrad <[email protected]>. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/tools/naive/http_proxy_socket.h"
+
+#include <cstring>
+#include <utility>
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/callback_helpers.h"
+#include "base/logging.h"
+#include "base/rand_util.h"
+#include "base/sys_byteorder.h"
+#include "net/base/ip_address.h"
+#include "net/base/net_errors.h"
+#include "net/log/net_log.h"
+
+namespace net {
+
+namespace {
+constexpr int kBufferSize = 64 * 1024;
+constexpr size_t kMaxHeaderSize = 64 * 1024;
+constexpr char kResponseHeader[] = "HTTP/1.1 200 OK\r\nPadding: ";
+constexpr int kResponseHeaderSize = sizeof(kResponseHeader) - 1;
+// A plain 200 is 10 bytes. Expected 48 bytes. "Padding" uses up 7 bytes.
+constexpr int kMinPaddingSize = 30;
+constexpr int kMaxPaddingSize = kMinPaddingSize + 32;
+}  // namespace
+
+HttpProxySocket::HttpProxySocket(
+    std::unique_ptr<StreamSocket> transport_socket,
+    const NetworkTrafficAnnotationTag& traffic_annotation)
+    : io_callback_(base::BindRepeating(&HttpProxySocket::OnIOComplete,
+                                       base::Unretained(this))),
+      transport_(std::move(transport_socket)),
+      next_state_(STATE_NONE),
+      completed_handshake_(false),
+      was_ever_used_(false),
+      header_write_size_(-1),
+      net_log_(transport_->NetLog()),
+      traffic_annotation_(traffic_annotation) {}
+
+HttpProxySocket::~HttpProxySocket() {
+  Disconnect();
+}
+
+const HostPortPair& HttpProxySocket::request_endpoint() const {
+  return request_endpoint_;
+}
+
+int HttpProxySocket::Connect(CompletionOnceCallback callback) {
+  DCHECK(transport_);
+  DCHECK_EQ(STATE_NONE, next_state_);
+  DCHECK(!user_callback_);
+
+  // If already connected, then just return OK.
+  if (completed_handshake_)
+    return OK;
+
+  next_state_ = STATE_HEADER_READ;
+  buffer_.clear();
+
+  int rv = DoLoop(OK);
+  if (rv == ERR_IO_PENDING) {
+    user_callback_ = std::move(callback);
+  }
+  return rv;
+}
+
+void HttpProxySocket::Disconnect() {
+  completed_handshake_ = false;
+  transport_->Disconnect();
+
+  // Reset other states to make sure they aren't mistakenly used later.
+  // These are the states initialized by Connect().
+  next_state_ = STATE_NONE;
+  user_callback_.Reset();
+}
+
+bool HttpProxySocket::IsConnected() const {
+  return completed_handshake_ && transport_->IsConnected();
+}
+
+bool HttpProxySocket::IsConnectedAndIdle() const {
+  return completed_handshake_ && transport_->IsConnectedAndIdle();
+}
+
+const NetLogWithSource& HttpProxySocket::NetLog() const {
+  return net_log_;
+}
+
+bool HttpProxySocket::WasEverUsed() const {
+  return was_ever_used_;
+}
+
+bool HttpProxySocket::WasAlpnNegotiated() const {
+  if (transport_) {
+    return transport_->WasAlpnNegotiated();
+  }
+  NOTREACHED();
+  return false;
+}
+
+NextProto HttpProxySocket::GetNegotiatedProtocol() const {
+  if (transport_) {
+    return transport_->GetNegotiatedProtocol();
+  }
+  NOTREACHED();
+  return kProtoUnknown;
+}
+
+bool HttpProxySocket::GetSSLInfo(SSLInfo* ssl_info) {
+  if (transport_) {
+    return transport_->GetSSLInfo(ssl_info);
+  }
+  NOTREACHED();
+  return false;
+}
+
+void HttpProxySocket::GetConnectionAttempts(ConnectionAttempts* out) const {
+  out->clear();
+}
+
+int64_t HttpProxySocket::GetTotalReceivedBytes() const {
+  return transport_->GetTotalReceivedBytes();
+}
+
+void HttpProxySocket::ApplySocketTag(const SocketTag& tag) {
+  return transport_->ApplySocketTag(tag);
+}
+
+// Read is called by the transport layer above to read. This can only be done
+// if the HTTP header is complete.
+int HttpProxySocket::Read(IOBuffer* buf,
+                          int buf_len,
+                          CompletionOnceCallback callback) {
+  DCHECK(completed_handshake_);
+  DCHECK_EQ(STATE_NONE, next_state_);
+  DCHECK(!user_callback_);
+  DCHECK(callback);
+
+  int rv = transport_->Read(
+      buf, buf_len,
+      base::BindOnce(&HttpProxySocket::OnReadWriteComplete,
+                     base::Unretained(this), std::move(callback)));
+  if (rv > 0)
+    was_ever_used_ = true;
+  return rv;
+}
+
+// Write is called by the transport layer. This can only be done if the
+// SOCKS handshake is complete.
+int HttpProxySocket::Write(
+    IOBuffer* buf,
+    int buf_len,
+    CompletionOnceCallback callback,
+    const NetworkTrafficAnnotationTag& traffic_annotation) {
+  DCHECK(completed_handshake_);
+  DCHECK_EQ(STATE_NONE, next_state_);
+  DCHECK(!user_callback_);
+  DCHECK(callback);
+
+  int rv = transport_->Write(
+      buf, buf_len,
+      base::BindOnce(&HttpProxySocket::OnReadWriteComplete,
+                     base::Unretained(this), std::move(callback)),
+      traffic_annotation);
+  if (rv > 0)
+    was_ever_used_ = true;
+  return rv;
+}
+
+int HttpProxySocket::SetReceiveBufferSize(int32_t size) {
+  return transport_->SetReceiveBufferSize(size);
+}
+
+int HttpProxySocket::SetSendBufferSize(int32_t size) {
+  return transport_->SetSendBufferSize(size);
+}
+
+void HttpProxySocket::DoCallback(int result) {
+  DCHECK_NE(ERR_IO_PENDING, result);
+  DCHECK(user_callback_);
+
+  // Since Run() may result in Read being called,
+  // clear user_callback_ up front.
+  std::move(user_callback_).Run(result);
+}
+
+void HttpProxySocket::OnIOComplete(int result) {
+  DCHECK_NE(STATE_NONE, next_state_);
+  int rv = DoLoop(result);
+  if (rv != ERR_IO_PENDING) {
+    DoCallback(rv);
+  }
+}
+
+void HttpProxySocket::OnReadWriteComplete(CompletionOnceCallback callback,
+                                          int result) {
+  DCHECK_NE(ERR_IO_PENDING, result);
+  DCHECK(callback);
+
+  if (result > 0)
+    was_ever_used_ = true;
+  std::move(callback).Run(result);
+}
+
+int HttpProxySocket::DoLoop(int last_io_result) {
+  DCHECK_NE(next_state_, STATE_NONE);
+  int rv = last_io_result;
+  do {
+    State state = next_state_;
+    next_state_ = STATE_NONE;
+    switch (state) {
+      case STATE_HEADER_READ:
+        DCHECK_EQ(OK, rv);
+        rv = DoHeaderRead();
+        break;
+      case STATE_HEADER_READ_COMPLETE:
+        rv = DoHeaderReadComplete(rv);
+        break;
+      case STATE_HEADER_WRITE:
+        DCHECK_EQ(OK, rv);
+        rv = DoHeaderWrite();
+        break;
+      case STATE_HEADER_WRITE_COMPLETE:
+        rv = DoHeaderWriteComplete(rv);
+        break;
+      default:
+        NOTREACHED() << "bad state";
+        rv = ERR_UNEXPECTED;
+        break;
+    }
+  } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
+  return rv;
+}
+
+int HttpProxySocket::DoHeaderRead() {
+  next_state_ = STATE_HEADER_READ_COMPLETE;
+
+  handshake_buf_ = new IOBuffer(kBufferSize);
+  return transport_->Read(handshake_buf_.get(), kBufferSize, io_callback_);
+}
+
+int HttpProxySocket::DoHeaderReadComplete(int result) {
+  if (result < 0)
+    return result;
+
+  if (result == 0) {
+    return ERR_CONNECTION_CLOSED;
+  }
+
+  buffer_.append(handshake_buf_->data(), result);
+  if (buffer_.size() > kMaxHeaderSize) {
+    return ERR_MSG_TOO_BIG;
+  }
+
+  auto header_end = buffer_.find("\r\n\r\n");
+  if (header_end == std::string::npos) {
+    next_state_ = STATE_HEADER_READ;
+    return OK;
+  }
+  if (header_end + 4 != buffer_.size()) {
+    return ERR_INVALID_ARGUMENT;
+  }
+
+  // HttpProxyClientSocket uses CONNECT for all endpoints.
+  auto first_line_end = buffer_.find("\r\n");
+  auto first_space = buffer_.find(' ');
+  if (first_space == std::string::npos || first_space + 1 >= first_line_end) {
+    return ERR_INVALID_ARGUMENT;
+  }
+  if (buffer_.compare(0, first_space, "CONNECT") != 0) {
+    return ERR_INVALID_ARGUMENT;
+  }
+  auto second_space = buffer_.find(' ', first_space + 1);
+  if (second_space == std::string::npos || second_space >= first_line_end) {
+    return ERR_INVALID_ARGUMENT;
+  }
+  request_endpoint_ = HostPortPair::FromString(
+      buffer_.substr(first_space + 1, second_space - (first_space + 1)));
+
+  next_state_ = STATE_HEADER_WRITE;
+  return OK;
+}
+
+int HttpProxySocket::DoHeaderWrite() {
+  next_state_ = STATE_HEADER_WRITE_COMPLETE;
+
+  // Adds padding.
+  int padding_size = base::RandInt(kMinPaddingSize, kMaxPaddingSize);
+  header_write_size_ = kResponseHeaderSize + padding_size + 4;
+  handshake_buf_ = new IOBuffer(header_write_size_);
+  char* p = handshake_buf_->data();
+  std::memcpy(p, kResponseHeader, kResponseHeaderSize);
+  std::memset(p + kResponseHeaderSize, '.', padding_size);
+  std::memcpy(p + kResponseHeaderSize + padding_size, "\r\n\r\n", 4);
+
+  return transport_->Write(handshake_buf_.get(), header_write_size_,
+                           io_callback_, traffic_annotation_);
+}
+
+int HttpProxySocket::DoHeaderWriteComplete(int result) {
+  if (result < 0)
+    return result;
+
+  if (result != header_write_size_) {
+    return ERR_FAILED;
+  }
+
+  completed_handshake_ = true;
+  next_state_ = STATE_NONE;
+  return OK;
+}
+
+int HttpProxySocket::GetPeerAddress(IPEndPoint* address) const {
+  return transport_->GetPeerAddress(address);
+}
+
+int HttpProxySocket::GetLocalAddress(IPEndPoint* address) const {
+  return transport_->GetLocalAddress(address);
+}
+
+}  // namespace net