net/socket/socks5_client

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This source file includes following definitions.
net_log_
Connect
Disconnect
IsConnected
IsConnectedAndIdle
SetSubresourceSpeculation
SetOmniboxSpeculation
WasEverUsed
UsingTCPFastOpen
WasNpnNegotiated
GetNegotiatedProtocol
GetSSLInfo
Read
Write
SetReceiveBufferSize
SetSendBufferSize
DoCallback
OnIOComplete
OnReadWriteComplete
DoLoop
DoGreetWrite
DoGreetWriteComplete
DoGreetRead
DoGreetReadComplete
BuildHandshakeWriteBuffer
DoHandshakeWrite
DoHandshakeWriteComplete
DoHandshakeRead
DoHandshakeReadComplete
GetPeerAddress
GetLocalAddress
// Copyright (c) 2012 The Chromium Authors. 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/socket/socks5_client_socket.h"

#include "base/basictypes.h"
#include "base/callback_helpers.h"
#include "base/compiler_specific.h"
#include "base/debug/trace_event.h"
#include "base/format_macros.h"
#include "base/strings/string_util.h"
#include "base/sys_byteorder.h"
#include "net/base/io_buffer.h"
#include "net/base/net_log.h"
#include "net/base/net_util.h"
#include "net/socket/client_socket_handle.h"

namespace net {

const unsigned int SOCKS5ClientSocket::kGreetReadHeaderSize = 2;
const unsigned int SOCKS5ClientSocket::kWriteHeaderSize = 10;
const unsigned int SOCKS5ClientSocket::kReadHeaderSize = 5;
const uint8 SOCKS5ClientSocket::kSOCKS5Version = 0x05;
const uint8 SOCKS5ClientSocket::kTunnelCommand = 0x01;
const uint8 SOCKS5ClientSocket::kNullByte = 0x00;

COMPILE_ASSERT(sizeof(struct in_addr) == 4, incorrect_system_size_of_IPv4);
COMPILE_ASSERT(sizeof(struct in6_addr) == 16, incorrect_system_size_of_IPv6);

SOCKS5ClientSocket::SOCKS5ClientSocket(
    scoped_ptr<ClientSocketHandle> transport_socket,
    const HostResolver::RequestInfo& req_info)
    : io_callback_(base::Bind(&SOCKS5ClientSocket::OnIOComplete,
                              base::Unretained(this))),
      transport_(transport_socket.Pass()),
      next_state_(STATE_NONE),
      completed_handshake_(false),
      bytes_sent_(0),
      bytes_received_(0),
      read_header_size(kReadHeaderSize),
      was_ever_used_(false),
      host_request_info_(req_info),
      net_log_(transport_->socket()->NetLog()) {
}

SOCKS5ClientSocket::~SOCKS5ClientSocket() {
  Disconnect();
}

int SOCKS5ClientSocket::Connect(const CompletionCallback& callback) {
  DCHECK(transport_.get());
  DCHECK(transport_->socket());
  DCHECK_EQ(STATE_NONE, next_state_);
  DCHECK(user_callback_.is_null());

  // If already connected, then just return OK.
  if (completed_handshake_)
    return OK;

  net_log_.BeginEvent(NetLog::TYPE_SOCKS5_CONNECT);

  next_state_ = STATE_GREET_WRITE;
  buffer_.clear();

  int rv = DoLoop(OK);
  if (rv == ERR_IO_PENDING) {
    user_callback_ = callback;
  } else {
    net_log_.EndEventWithNetErrorCode(NetLog::TYPE_SOCKS5_CONNECT, rv);
  }
  return rv;
}

void SOCKS5ClientSocket::Disconnect() {
  completed_handshake_ = false;
  transport_->socket()->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 SOCKS5ClientSocket::IsConnected() const {
  return completed_handshake_ && transport_->socket()->IsConnected();
}

bool SOCKS5ClientSocket::IsConnectedAndIdle() const {
  return completed_handshake_ && transport_->socket()->IsConnectedAndIdle();
}

const BoundNetLog& SOCKS5ClientSocket::NetLog() const {
  return net_log_;
}

void SOCKS5ClientSocket::SetSubresourceSpeculation() {
  if (transport_.get() && transport_->socket()) {
    transport_->socket()->SetSubresourceSpeculation();
  } else {
    NOTREACHED();
  }
}

void SOCKS5ClientSocket::SetOmniboxSpeculation() {
  if (transport_.get() && transport_->socket()) {
    transport_->socket()->SetOmniboxSpeculation();
  } else {
    NOTREACHED();
  }
}

bool SOCKS5ClientSocket::WasEverUsed() const {
  return was_ever_used_;
}

bool SOCKS5ClientSocket::UsingTCPFastOpen() const {
  if (transport_.get() && transport_->socket()) {
    return transport_->socket()->UsingTCPFastOpen();
  }
  NOTREACHED();
  return false;
}

bool SOCKS5ClientSocket::WasNpnNegotiated() const {
  if (transport_.get() && transport_->socket()) {
    return transport_->socket()->WasNpnNegotiated();
  }
  NOTREACHED();
  return false;
}

NextProto SOCKS5ClientSocket::GetNegotiatedProtocol() const {
  if (transport_.get() && transport_->socket()) {
    return transport_->socket()->GetNegotiatedProtocol();
  }
  NOTREACHED();
  return kProtoUnknown;
}

bool SOCKS5ClientSocket::GetSSLInfo(SSLInfo* ssl_info) {
  if (transport_.get() && transport_->socket()) {
    return transport_->socket()->GetSSLInfo(ssl_info);
  }
  NOTREACHED();
  return false;

}

// Read is called by the transport layer above to read. This can only be done
// if the SOCKS handshake is complete.
int SOCKS5ClientSocket::Read(IOBuffer* buf, int buf_len,
                             const CompletionCallback& callback) {
  DCHECK(completed_handshake_);
  DCHECK_EQ(STATE_NONE, next_state_);
  DCHECK(user_callback_.is_null());
  DCHECK(!callback.is_null());

  int rv = transport_->socket()->Read(
      buf, buf_len,
      base::Bind(&SOCKS5ClientSocket::OnReadWriteComplete,
                 base::Unretained(this), 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 SOCKS5ClientSocket::Write(IOBuffer* buf, int buf_len,
                              const CompletionCallback& callback) {
  DCHECK(completed_handshake_);
  DCHECK_EQ(STATE_NONE, next_state_);
  DCHECK(user_callback_.is_null());
  DCHECK(!callback.is_null());

  int rv = transport_->socket()->Write(
      buf, buf_len,
      base::Bind(&SOCKS5ClientSocket::OnReadWriteComplete,
                 base::Unretained(this), callback));
  if (rv > 0)
    was_ever_used_ = true;
  return rv;
}

int SOCKS5ClientSocket::SetReceiveBufferSize(int32 size) {
  return transport_->socket()->SetReceiveBufferSize(size);
}

int SOCKS5ClientSocket::SetSendBufferSize(int32 size) {
  return transport_->socket()->SetSendBufferSize(size);
}

void SOCKS5ClientSocket::DoCallback(int result) {
  DCHECK_NE(ERR_IO_PENDING, result);
  DCHECK(!user_callback_.is_null());

  // Since Run() may result in Read being called,
  // clear user_callback_ up front.
  base::ResetAndReturn(&user_callback_).Run(result);
}

void SOCKS5ClientSocket::OnIOComplete(int result) {
  DCHECK_NE(STATE_NONE, next_state_);
  int rv = DoLoop(result);
  if (rv != ERR_IO_PENDING) {
    net_log_.EndEvent(NetLog::TYPE_SOCKS5_CONNECT);
    DoCallback(rv);
  }
}

void SOCKS5ClientSocket::OnReadWriteComplete(const CompletionCallback& callback,
                                             int result) {
  DCHECK_NE(ERR_IO_PENDING, result);
  DCHECK(!callback.is_null());

  if (result > 0)
    was_ever_used_ = true;
  callback.Run(result);
}

int SOCKS5ClientSocket::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_GREET_WRITE:
        DCHECK_EQ(OK, rv);
        net_log_.BeginEvent(NetLog::TYPE_SOCKS5_GREET_WRITE);
        rv = DoGreetWrite();
        break;
      case STATE_GREET_WRITE_COMPLETE:
        rv = DoGreetWriteComplete(rv);
        net_log_.EndEventWithNetErrorCode(NetLog::TYPE_SOCKS5_GREET_WRITE, rv);
        break;
      case STATE_GREET_READ:
        DCHECK_EQ(OK, rv);
        net_log_.BeginEvent(NetLog::TYPE_SOCKS5_GREET_READ);
        rv = DoGreetRead();
        break;
      case STATE_GREET_READ_COMPLETE:
        rv = DoGreetReadComplete(rv);
        net_log_.EndEventWithNetErrorCode(NetLog::TYPE_SOCKS5_GREET_READ, rv);
        break;
      case STATE_HANDSHAKE_WRITE:
        DCHECK_EQ(OK, rv);
        net_log_.BeginEvent(NetLog::TYPE_SOCKS5_HANDSHAKE_WRITE);
        rv = DoHandshakeWrite();
        break;
      case STATE_HANDSHAKE_WRITE_COMPLETE:
        rv = DoHandshakeWriteComplete(rv);
        net_log_.EndEventWithNetErrorCode(
            NetLog::TYPE_SOCKS5_HANDSHAKE_WRITE, rv);
        break;
      case STATE_HANDSHAKE_READ:
        DCHECK_EQ(OK, rv);
        net_log_.BeginEvent(NetLog::TYPE_SOCKS5_HANDSHAKE_READ);
        rv = DoHandshakeRead();
        break;
      case STATE_HANDSHAKE_READ_COMPLETE:
        rv = DoHandshakeReadComplete(rv);
        net_log_.EndEventWithNetErrorCode(
            NetLog::TYPE_SOCKS5_HANDSHAKE_READ, rv);
        break;
      default:
        NOTREACHED() << "bad state";
        rv = ERR_UNEXPECTED;
        break;
    }
  } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
  return rv;
}

const char kSOCKS5GreetWriteData[] = { 0x05, 0x01, 0x00 };  // no authentication

int SOCKS5ClientSocket::DoGreetWrite() {
  // Since we only have 1 byte to send the hostname length in, if the
  // URL has a hostname longer than 255 characters we can't send it.
  if (0xFF < host_request_info_.hostname().size()) {
    net_log_.AddEvent(NetLog::TYPE_SOCKS_HOSTNAME_TOO_BIG);
    return ERR_SOCKS_CONNECTION_FAILED;
  }

  if (buffer_.empty()) {
    buffer_ = std::string(kSOCKS5GreetWriteData,
                          arraysize(kSOCKS5GreetWriteData));
    bytes_sent_ = 0;
  }

  next_state_ = STATE_GREET_WRITE_COMPLETE;
  size_t handshake_buf_len = buffer_.size() - bytes_sent_;
  handshake_buf_ = new IOBuffer(handshake_buf_len);
  memcpy(handshake_buf_->data(), &buffer_.data()[bytes_sent_],
         handshake_buf_len);
  return transport_->socket()
      ->Write(handshake_buf_.get(), handshake_buf_len, io_callback_);
}

int SOCKS5ClientSocket::DoGreetWriteComplete(int result) {
  if (result < 0)
    return result;

  bytes_sent_ += result;
  if (bytes_sent_ == buffer_.size()) {
    buffer_.clear();
    bytes_received_ = 0;
    next_state_ = STATE_GREET_READ;
  } else {
    next_state_ = STATE_GREET_WRITE;
  }
  return OK;
}

int SOCKS5ClientSocket::DoGreetRead() {
  next_state_ = STATE_GREET_READ_COMPLETE;
  size_t handshake_buf_len = kGreetReadHeaderSize - bytes_received_;
  handshake_buf_ = new IOBuffer(handshake_buf_len);
  return transport_->socket()
      ->Read(handshake_buf_.get(), handshake_buf_len, io_callback_);
}

int SOCKS5ClientSocket::DoGreetReadComplete(int result) {
  if (result < 0)
    return result;

  if (result == 0) {
    net_log_.AddEvent(NetLog::TYPE_SOCKS_UNEXPECTEDLY_CLOSED_DURING_GREETING);
    return ERR_SOCKS_CONNECTION_FAILED;
  }

  bytes_received_ += result;
  buffer_.append(handshake_buf_->data(), result);
  if (bytes_received_ < kGreetReadHeaderSize) {
    next_state_ = STATE_GREET_READ;
    return OK;
  }

  // Got the greet data.
  if (buffer_[0] != kSOCKS5Version) {
    net_log_.AddEvent(NetLog::TYPE_SOCKS_UNEXPECTED_VERSION,
                      NetLog::IntegerCallback("version", buffer_[0]));
    return ERR_SOCKS_CONNECTION_FAILED;
  }
  if (buffer_[1] != 0x00) {
    net_log_.AddEvent(NetLog::TYPE_SOCKS_UNEXPECTED_AUTH,
                      NetLog::IntegerCallback("method", buffer_[1]));
    return ERR_SOCKS_CONNECTION_FAILED;
  }

  buffer_.clear();
  next_state_ = STATE_HANDSHAKE_WRITE;
  return OK;
}

int SOCKS5ClientSocket::BuildHandshakeWriteBuffer(std::string* handshake)
    const {
  DCHECK(handshake->empty());

  handshake->push_back(kSOCKS5Version);
  handshake->push_back(kTunnelCommand);  // Connect command
  handshake->push_back(kNullByte);  // Reserved null

  handshake->push_back(kEndPointDomain);  // The type of the address.

  DCHECK_GE(static_cast<size_t>(0xFF), host_request_info_.hostname().size());

  // First add the size of the hostname, followed by the hostname.
  handshake->push_back(static_cast<unsigned char>(
      host_request_info_.hostname().size()));
  handshake->append(host_request_info_.hostname());

  uint16 nw_port = base::HostToNet16(host_request_info_.port());
  handshake->append(reinterpret_cast<char*>(&nw_port), sizeof(nw_port));
  return OK;
}

// Writes the SOCKS handshake data to the underlying socket connection.
int SOCKS5ClientSocket::DoHandshakeWrite() {
  next_state_ = STATE_HANDSHAKE_WRITE_COMPLETE;

  if (buffer_.empty()) {
    int rv = BuildHandshakeWriteBuffer(&buffer_);
    if (rv != OK)
      return rv;
    bytes_sent_ = 0;
  }

  int handshake_buf_len = buffer_.size() - bytes_sent_;
  DCHECK_LT(0, handshake_buf_len);
  handshake_buf_ = new IOBuffer(handshake_buf_len);
  memcpy(handshake_buf_->data(), &buffer_[bytes_sent_],
         handshake_buf_len);
  return transport_->socket()
      ->Write(handshake_buf_.get(), handshake_buf_len, io_callback_);
}

int SOCKS5ClientSocket::DoHandshakeWriteComplete(int result) {
  if (result < 0)
    return result;

  // We ignore the case when result is 0, since the underlying Write
  // may return spurious writes while waiting on the socket.

  bytes_sent_ += result;
  if (bytes_sent_ == buffer_.size()) {
    next_state_ = STATE_HANDSHAKE_READ;
    buffer_.clear();
  } else if (bytes_sent_ < buffer_.size()) {
    next_state_ = STATE_HANDSHAKE_WRITE;
  } else {
    NOTREACHED();
  }

  return OK;
}

int SOCKS5ClientSocket::DoHandshakeRead() {
  next_state_ = STATE_HANDSHAKE_READ_COMPLETE;

  if (buffer_.empty()) {
    bytes_received_ = 0;
    read_header_size = kReadHeaderSize;
  }

  int handshake_buf_len = read_header_size - bytes_received_;
  handshake_buf_ = new IOBuffer(handshake_buf_len);
  return transport_->socket()
      ->Read(handshake_buf_.get(), handshake_buf_len, io_callback_);
}

int SOCKS5ClientSocket::DoHandshakeReadComplete(int result) {
  if (result < 0)
    return result;

  // The underlying socket closed unexpectedly.
  if (result == 0) {
    net_log_.AddEvent(NetLog::TYPE_SOCKS_UNEXPECTEDLY_CLOSED_DURING_HANDSHAKE);
    return ERR_SOCKS_CONNECTION_FAILED;
  }

  buffer_.append(handshake_buf_->data(), result);
  bytes_received_ += result;

  // When the first few bytes are read, check how many more are required
  // and accordingly increase them
  if (bytes_received_ == kReadHeaderSize) {
    if (buffer_[0] != kSOCKS5Version || buffer_[2] != kNullByte) {
      net_log_.AddEvent(NetLog::TYPE_SOCKS_UNEXPECTED_VERSION,
                        NetLog::IntegerCallback("version", buffer_[0]));
      return ERR_SOCKS_CONNECTION_FAILED;
    }
    if (buffer_[1] != 0x00) {
      net_log_.AddEvent(NetLog::TYPE_SOCKS_SERVER_ERROR,
                        NetLog::IntegerCallback("error_code", buffer_[1]));
      return ERR_SOCKS_CONNECTION_FAILED;
    }

    // We check the type of IP/Domain the server returns and accordingly
    // increase the size of the response. For domains, we need to read the
    // size of the domain, so the initial request size is upto the domain
    // size. Since for IPv4/IPv6 the size is fixed and hence no 'size' is
    // read, we substract 1 byte from the additional request size.
    SocksEndPointAddressType address_type =
        static_cast<SocksEndPointAddressType>(buffer_[3]);
    if (address_type == kEndPointDomain)
      read_header_size += static_cast<uint8>(buffer_[4]);
    else if (address_type == kEndPointResolvedIPv4)
      read_header_size += sizeof(struct in_addr) - 1;
    else if (address_type == kEndPointResolvedIPv6)
      read_header_size += sizeof(struct in6_addr) - 1;
    else {
      net_log_.AddEvent(NetLog::TYPE_SOCKS_UNKNOWN_ADDRESS_TYPE,
                        NetLog::IntegerCallback("address_type", buffer_[3]));
      return ERR_SOCKS_CONNECTION_FAILED;
    }

    read_header_size += 2;  // for the port.
    next_state_ = STATE_HANDSHAKE_READ;
    return OK;
  }

  // When the final bytes are read, setup handshake. We ignore the rest
  // of the response since they represent the SOCKSv5 endpoint and have
  // no use when doing a tunnel connection.
  if (bytes_received_ == read_header_size) {
    completed_handshake_ = true;
    buffer_.clear();
    next_state_ = STATE_NONE;
    return OK;
  }

  next_state_ = STATE_HANDSHAKE_READ;
  return OK;
}

int SOCKS5ClientSocket::GetPeerAddress(IPEndPoint* address) const {
  return transport_->socket()->GetPeerAddress(address);
}

int SOCKS5ClientSocket::GetLocalAddress(IPEndPoint* address) const {
  return transport_->socket()->GetLocalAddress(address);
}

}  // namespace net
/* [<][>][^][v][top][bottom][index][help] */
root/net/socket/socks5_client_socket.cc

DEFINITIONS
