remoting/host/gnubby_socket.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "remoting/host/gnubby_socket.h"
   6
   7 #include "base/macros.h"
   8 #include "base/timer/timer.h"
   9 #include "net/socket/stream_listen_socket.h"
  10
  11 namespace remoting {
  12
  13 namespace {
  14
  15 const size_t kRequestSizeBytes = 4;
  16 const size_t kMaxRequestLength = 16384;
  17 const unsigned int kRequestTimeoutSeconds = 60;
  18
  19 // SSH Failure Code
  20 const char kSshError[] = {0x05};
  21
  22 }  // namespace
  23
  24 GnubbySocket::GnubbySocket(scoped_ptr<net::StreamListenSocket> socket,
  25                            const base::Closure& timeout_callback)
  26     : socket_(socket.Pass()) {
  27   timer_.reset(new base::Timer(false, false));
  28   timer_->Start(FROM_HERE,
  29                 base::TimeDelta::FromSeconds(kRequestTimeoutSeconds),
  30                 timeout_callback);
  31 }
  32
  33 GnubbySocket::~GnubbySocket() {}
  34
  35 void GnubbySocket::AddRequestData(const char* data, int data_len) {
  36   DCHECK(CalledOnValidThread());
  37
  38   request_data_.insert(request_data_.end(), data, data + data_len);
  39   ResetTimer();
  40 }
  41
  42 void GnubbySocket::GetAndClearRequestData(std::string* data_out) {
  43   DCHECK(CalledOnValidThread());
  44   DCHECK(IsRequestComplete() && !IsRequestTooLarge());
  45
  46   // The request size is not part of the data; don't send it.
  47   data_out->assign(request_data_.begin() + kRequestSizeBytes,
  48                    request_data_.end());
  49   request_data_.clear();
  50 }
  51
  52 bool GnubbySocket::IsRequestComplete() const {
  53   DCHECK(CalledOnValidThread());
  54
  55   if (request_data_.size() < kRequestSizeBytes)
  56     return false;
  57   return GetRequestLength() <= request_data_.size();
  58 }
  59
  60 bool GnubbySocket::IsRequestTooLarge() const {
  61   DCHECK(CalledOnValidThread());
  62
  63   if (request_data_.size() < kRequestSizeBytes)
  64     return false;
  65   return GetRequestLength() > kMaxRequestLength;
  66 }
  67
  68 void GnubbySocket::SendResponse(const std::string& response_data) {
  69   DCHECK(CalledOnValidThread());
  70
  71   socket_->Send(GetResponseLengthAsBytes(response_data));
  72   socket_->Send(response_data);
  73   ResetTimer();
  74 }
  75
  76 void GnubbySocket::SendSshError() {
  77   DCHECK(CalledOnValidThread());
  78
  79   SendResponse(std::string(kSshError, arraysize(kSshError)));
  80 }
  81
  82 bool GnubbySocket::IsSocket(net::StreamListenSocket* socket) const {
  83   return socket == socket_.get();
  84 }
  85
  86 void GnubbySocket::SetTimerForTesting(scoped_ptr<base::Timer> timer) {
  87   timer->Start(FROM_HERE, timer_->GetCurrentDelay(), timer_->user_task());
  88   timer_ = timer.Pass();
  89 }
  90
  91 size_t GnubbySocket::GetRequestLength() const {
  92   DCHECK(request_data_.size() >= kRequestSizeBytes);
  93
  94   return ((request_data_[0] & 255) << 24) + ((request_data_[1] & 255) << 16) +
  95          ((request_data_[2] & 255) << 8) + (request_data_[3] & 255) +
  96          kRequestSizeBytes;
  97 }
  98
  99 std::string GnubbySocket::GetResponseLengthAsBytes(
 100     const std::string& response) const {
 101   std::string response_len;
 102   int len = response.size();
 103
 104   response_len.push_back((len >> 24) & 255);
 105   response_len.push_back((len >> 16) & 255);
 106   response_len.push_back((len >> 8) & 255);
 107   response_len.push_back(len & 255);
 108
 109   return response_len;
 110 }
 111
 112 void GnubbySocket::ResetTimer() {
 113   if (timer_->IsRunning())
 114     timer_->Reset();
 115 }
 116
 117 }  // namespace remoting