// 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/http/http_proxy_client_socket_pool.h"

#include <algorithm>

#include "base/compiler_specific.h"
#include "base/time/time.h"
#include "base/values.h"
#include "net/base/load_flags.h"
#include "net/base/net_errors.h"
#include "net/base/proxy_delegate.h"
#include "net/http/http_network_session.h"
#include "net/http/http_proxy_client_socket.h"
#include "net/socket/client_socket_factory.h"
#include "net/socket/client_socket_handle.h"
#include "net/socket/client_socket_pool_base.h"
#include "net/socket/ssl_client_socket.h"
#include "net/socket/ssl_client_socket_pool.h"
#include "net/socket/transport_client_socket_pool.h"
#include "net/spdy/spdy_proxy_client_socket.h"
#include "net/spdy/spdy_session.h"
#include "net/spdy/spdy_session_pool.h"
#include "net/spdy/spdy_stream.h"
#include "net/ssl/ssl_cert_request_info.h"
#include "url/gurl.h"

namespace net {

HttpProxySocketParams::HttpProxySocketParams(
    const scoped_refptr<TransportSocketParams>& transport_params,
    const scoped_refptr<SSLSocketParams>& ssl_params,
    const std::string& user_agent,
    const HostPortPair& endpoint,
    HttpAuthCache* http_auth_cache,
    HttpAuthHandlerFactory* http_auth_handler_factory,
    SpdySessionPool* spdy_session_pool,
    bool tunnel,
    ProxyDelegate* proxy_delegate)
    : transport_params_(transport_params),
      ssl_params_(ssl_params),
      spdy_session_pool_(spdy_session_pool),
      user_agent_(user_agent),
      endpoint_(endpoint),
      http_auth_cache_(tunnel ? http_auth_cache : NULL),
      http_auth_handler_factory_(tunnel ? http_auth_handler_factory : NULL),
      tunnel_(tunnel),
      proxy_delegate_(proxy_delegate) {
  DCHECK((transport_params.get() == NULL && ssl_params.get() != NULL) ||
         (transport_params.get() != NULL && ssl_params.get() == NULL));
  if (transport_params_.get()) {
    ignore_limits_ = transport_params->ignore_limits();
  } else {
    ignore_limits_ = ssl_params->ignore_limits();
  }
}

const HostResolver::RequestInfo& HttpProxySocketParams::destination() const {
  if (transport_params_.get() == NULL) {
    return ssl_params_->GetDirectConnectionParams()->destination();
  } else {
    return transport_params_->destination();
  }
}

HttpProxySocketParams::~HttpProxySocketParams() {}

// HttpProxyConnectJobs will time out after this many seconds.  Note this is on
// top of the timeout for the transport socket.
// TODO(kundaji): Proxy connect timeout should be independent of platform and be
// based on proxy. Bug http://crbug.com/407446.
#if defined(OS_ANDROID) || defined(OS_IOS)
static const int kHttpProxyConnectJobTimeoutInSeconds = 10;
#else
static const int kHttpProxyConnectJobTimeoutInSeconds = 30;
#endif

HttpProxyConnectJob::HttpProxyConnectJob(
    const std::string& group_name,
    RequestPriority priority,
    const scoped_refptr<HttpProxySocketParams>& params,
    const base::TimeDelta& timeout_duration,
    TransportClientSocketPool* transport_pool,
    SSLClientSocketPool* ssl_pool,
    Delegate* delegate,
    NetLog* net_log)
    : ConnectJob(group_name, timeout_duration, priority, delegate,
                 BoundNetLog::Make(net_log, NetLog::SOURCE_CONNECT_JOB)),
      params_(params),
      transport_pool_(transport_pool),
      ssl_pool_(ssl_pool),
      using_spdy_(false),
      protocol_negotiated_(kProtoUnknown),
      weak_ptr_factory_(this) {
    callback_= base::Bind(&HttpProxyConnectJob::OnIOComplete,
                           weak_ptr_factory_.GetWeakPtr());
}

HttpProxyConnectJob::~HttpProxyConnectJob() {}

LoadState HttpProxyConnectJob::GetLoadState() const {
  switch (next_state_) {
    case STATE_TCP_CONNECT:
    case STATE_TCP_CONNECT_COMPLETE:
    case STATE_SSL_CONNECT:
    case STATE_SSL_CONNECT_COMPLETE:
      return transport_socket_handle_->GetLoadState();
    case STATE_HTTP_PROXY_CONNECT:
    case STATE_HTTP_PROXY_CONNECT_COMPLETE:
    case STATE_SPDY_PROXY_CREATE_STREAM:
    case STATE_SPDY_PROXY_CREATE_STREAM_COMPLETE:
      return LOAD_STATE_ESTABLISHING_PROXY_TUNNEL;
    default:
      NOTREACHED();
      return LOAD_STATE_IDLE;
  }
}

void HttpProxyConnectJob::GetAdditionalErrorState(ClientSocketHandle * handle) {
  if (error_response_info_.cert_request_info.get()) {
    handle->set_ssl_error_response_info(error_response_info_);
    handle->set_is_ssl_error(true);
  }
}

void HttpProxyConnectJob::OnIOComplete(int result) {
  int rv = DoLoop(result);
  if (rv != ERR_IO_PENDING) {
    NotifyProxyDelegateOfCompletion(rv);
    NotifyDelegateOfCompletion(rv);  // Deletes |this|
  }
}

int HttpProxyConnectJob::DoLoop(int result) {
  DCHECK_NE(next_state_, STATE_NONE);

  int rv = result;
  do {
    State state = next_state_;
    next_state_ = STATE_NONE;
    switch (state) {
      case STATE_TCP_CONNECT:
        DCHECK_EQ(OK, rv);
        rv = DoTransportConnect();
        break;
      case STATE_TCP_CONNECT_COMPLETE:
        rv = DoTransportConnectComplete(rv);
        break;
      case STATE_SSL_CONNECT:
        DCHECK_EQ(OK, rv);
        rv = DoSSLConnect();
        break;
      case STATE_SSL_CONNECT_COMPLETE:
        rv = DoSSLConnectComplete(rv);
        break;
      case STATE_HTTP_PROXY_CONNECT:
        DCHECK_EQ(OK, rv);
        rv = DoHttpProxyConnect();
        break;
      case STATE_HTTP_PROXY_CONNECT_COMPLETE:
        rv = DoHttpProxyConnectComplete(rv);
        break;
      case STATE_SPDY_PROXY_CREATE_STREAM:
        DCHECK_EQ(OK, rv);
        rv = DoSpdyProxyCreateStream();
        break;
      case STATE_SPDY_PROXY_CREATE_STREAM_COMPLETE:
        rv = DoSpdyProxyCreateStreamComplete(rv);
        break;
      default:
        NOTREACHED() << "bad state";
        rv = ERR_FAILED;
        break;
    }
  } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);

  return rv;
}

int HttpProxyConnectJob::DoTransportConnect() {
  next_state_ = STATE_TCP_CONNECT_COMPLETE;
  transport_socket_handle_.reset(new ClientSocketHandle());
  return transport_socket_handle_->Init(group_name(),
                                        params_->transport_params(),
                                        priority(),
                                        callback_,
                                        transport_pool_,
                                        net_log());
}

int HttpProxyConnectJob::DoTransportConnectComplete(int result) {
  if (result != OK)
    return ERR_PROXY_CONNECTION_FAILED;

  // Reset the timer to just the length of time allowed for HttpProxy handshake
  // so that a fast TCP connection plus a slow HttpProxy failure doesn't take
  // longer to timeout than it should.
  ResetTimer(base::TimeDelta::FromSeconds(
      kHttpProxyConnectJobTimeoutInSeconds));

  next_state_ = STATE_HTTP_PROXY_CONNECT;
  return result;
}

int HttpProxyConnectJob::DoSSLConnect() {
  if (params_->tunnel()) {
    SpdySessionKey key(params_->destination().host_port_pair(),
                       ProxyServer::Direct(),
                       PRIVACY_MODE_DISABLED);
    if (params_->spdy_session_pool()->FindAvailableSession(key, net_log())) {
      using_spdy_ = true;
      next_state_ = STATE_SPDY_PROXY_CREATE_STREAM;
      return OK;
    }
  }
  next_state_ = STATE_SSL_CONNECT_COMPLETE;
  transport_socket_handle_.reset(new ClientSocketHandle());
  return transport_socket_handle_->Init(
      group_name(), params_->ssl_params(), priority(), callback_,
      ssl_pool_, net_log());
}

int HttpProxyConnectJob::DoSSLConnectComplete(int result) {
  if (result == ERR_SSL_CLIENT_AUTH_CERT_NEEDED) {
    error_response_info_ = transport_socket_handle_->ssl_error_response_info();
    DCHECK(error_response_info_.cert_request_info.get());
    error_response_info_.cert_request_info->is_proxy = true;
    return result;
  }
  if (IsCertificateError(result)) {
    if (params_->ssl_params()->load_flags() & LOAD_IGNORE_ALL_CERT_ERRORS) {
      result = OK;
    } else {
      // TODO(rch): allow the user to deal with proxy cert errors in the
      // same way as server cert errors.
      transport_socket_handle_->socket()->Disconnect();
      return ERR_PROXY_CERTIFICATE_INVALID;
    }
  }
  // A SPDY session to the proxy completed prior to resolving the proxy
  // hostname. Surface this error, and allow the delegate to retry.
  // See crbug.com/334413.
  if (result == ERR_SPDY_SESSION_ALREADY_EXISTS) {
    DCHECK(!transport_socket_handle_->socket());
    return ERR_SPDY_SESSION_ALREADY_EXISTS;
  }
  if (result < 0) {
    if (transport_socket_handle_->socket())
      transport_socket_handle_->socket()->Disconnect();
    return ERR_PROXY_CONNECTION_FAILED;
  }

  SSLClientSocket* ssl =
      static_cast<SSLClientSocket*>(transport_socket_handle_->socket());
  protocol_negotiated_ = ssl->GetNegotiatedProtocol();
  using_spdy_ = NextProtoIsSPDY(protocol_negotiated_);

  // Reset the timer to just the length of time allowed for HttpProxy handshake
  // so that a fast SSL connection plus a slow HttpProxy failure doesn't take
  // longer to timeout than it should.
  ResetTimer(base::TimeDelta::FromSeconds(
      kHttpProxyConnectJobTimeoutInSeconds));
  // TODO(rch): If we ever decide to implement a "trusted" SPDY proxy
  // (one that we speak SPDY over SSL to, but to which we send HTTPS
  // request directly instead of through CONNECT tunnels, then we
  // need to add a predicate to this if statement so we fall through
  // to the else case. (HttpProxyClientSocket currently acts as
  // a "trusted" SPDY proxy).
  if (using_spdy_ && params_->tunnel()) {
    next_state_ = STATE_SPDY_PROXY_CREATE_STREAM;
  } else {
    next_state_ = STATE_HTTP_PROXY_CONNECT;
  }
  return result;
}

int HttpProxyConnectJob::DoHttpProxyConnect() {
  next_state_ = STATE_HTTP_PROXY_CONNECT_COMPLETE;
  const HostResolver::RequestInfo& tcp_destination = params_->destination();
  const HostPortPair& proxy_server = tcp_destination.host_port_pair();

  // Add a HttpProxy connection on top of the tcp socket.
  transport_socket_.reset(
      new HttpProxyClientSocket(transport_socket_handle_.release(),
                                params_->user_agent(),
                                params_->endpoint(),
                                proxy_server,
                                params_->http_auth_cache(),
                                params_->http_auth_handler_factory(),
                                params_->tunnel(),
                                using_spdy_,
                                protocol_negotiated_,
                                params_->proxy_delegate(),
                                params_->ssl_params().get() != NULL));
  return transport_socket_->Connect(callback_);
}

int HttpProxyConnectJob::DoHttpProxyConnectComplete(int result) {
  if (result == OK || result == ERR_PROXY_AUTH_REQUESTED ||
      result == ERR_HTTPS_PROXY_TUNNEL_RESPONSE) {
    SetSocket(transport_socket_.Pass());
  }

  if (result == ERR_HTTP_1_1_REQUIRED)
    return ERR_PROXY_HTTP_1_1_REQUIRED;

  return result;
}

int HttpProxyConnectJob::DoSpdyProxyCreateStream() {
  DCHECK(using_spdy_);
  DCHECK(params_->tunnel());
  SpdySessionKey key(params_->destination().host_port_pair(),
                     ProxyServer::Direct(),
                     PRIVACY_MODE_DISABLED);
  SpdySessionPool* spdy_pool = params_->spdy_session_pool();
  base::WeakPtr<SpdySession> spdy_session =
      spdy_pool->FindAvailableSession(key, net_log());
  // It's possible that a session to the proxy has recently been created
  if (spdy_session) {
    if (transport_socket_handle_.get()) {
      if (transport_socket_handle_->socket())
        transport_socket_handle_->socket()->Disconnect();
      transport_socket_handle_->Reset();
    }
  } else {
    // Create a session direct to the proxy itself
    spdy_session =
        spdy_pool->CreateAvailableSessionFromSocket(
            key, transport_socket_handle_.Pass(),
            net_log(), OK, /*using_ssl_*/ true);
    DCHECK(spdy_session);
  }

  next_state_ = STATE_SPDY_PROXY_CREATE_STREAM_COMPLETE;
  return spdy_stream_request_.StartRequest(
      SPDY_BIDIRECTIONAL_STREAM, spdy_session,
      GURL("https://" + params_->endpoint().ToString()), priority(),
      spdy_session->net_log(), callback_);
}

int HttpProxyConnectJob::DoSpdyProxyCreateStreamComplete(int result) {
  if (result < 0)
    return result;

  next_state_ = STATE_HTTP_PROXY_CONNECT_COMPLETE;
  base::WeakPtr<SpdyStream> stream = spdy_stream_request_.ReleaseStream();
  DCHECK(stream.get());
  // |transport_socket_| will set itself as |stream|'s delegate.
  transport_socket_.reset(
      new SpdyProxyClientSocket(stream,
                                params_->user_agent(),
                                params_->endpoint(),
                                params_->destination().host_port_pair(),
                                net_log(),
                                params_->http_auth_cache(),
                                params_->http_auth_handler_factory()));
  return transport_socket_->Connect(callback_);
}

void HttpProxyConnectJob::NotifyProxyDelegateOfCompletion(int result) {
  if (!params_->proxy_delegate())
    return;

  const HostPortPair& proxy_server = params_->destination().host_port_pair();
  params_->proxy_delegate()->OnTunnelConnectCompleted(params_->endpoint(),
                                                      proxy_server,
                                                      result);
}

int HttpProxyConnectJob::ConnectInternal() {
  if (params_->transport_params().get()) {
    next_state_ = STATE_TCP_CONNECT;
  } else {
    next_state_ = STATE_SSL_CONNECT;
  }

  int rv = DoLoop(OK);
  if (rv != ERR_IO_PENDING) {
    NotifyProxyDelegateOfCompletion(rv);
  }

  return rv;
}

HttpProxyClientSocketPool::
HttpProxyConnectJobFactory::HttpProxyConnectJobFactory(
    TransportClientSocketPool* transport_pool,
    SSLClientSocketPool* ssl_pool,
    NetLog* net_log)
    : transport_pool_(transport_pool),
      ssl_pool_(ssl_pool),
      net_log_(net_log) {
  base::TimeDelta max_pool_timeout = base::TimeDelta();

// TODO(kundaji): Proxy connect timeout should be independent of platform and be
// based on proxy. Bug http://crbug.com/407446.
#if (defined(OS_ANDROID) || defined(OS_IOS))
#else
  if (transport_pool_)
    max_pool_timeout = transport_pool_->ConnectionTimeout();
  if (ssl_pool_)
    max_pool_timeout = std::max(max_pool_timeout,
                                ssl_pool_->ConnectionTimeout());
#endif
  timeout_ = max_pool_timeout +
    base::TimeDelta::FromSeconds(kHttpProxyConnectJobTimeoutInSeconds);
}


scoped_ptr<ConnectJob>
HttpProxyClientSocketPool::HttpProxyConnectJobFactory::NewConnectJob(
    const std::string& group_name,
    const PoolBase::Request& request,
    ConnectJob::Delegate* delegate) const {
  return scoped_ptr<ConnectJob>(new HttpProxyConnectJob(group_name,
                                                        request.priority(),
                                                        request.params(),
                                                        ConnectionTimeout(),
                                                        transport_pool_,
                                                        ssl_pool_,
                                                        delegate,
                                                        net_log_));
}

base::TimeDelta
HttpProxyClientSocketPool::HttpProxyConnectJobFactory::ConnectionTimeout(
    ) const {
  return timeout_;
}

HttpProxyClientSocketPool::HttpProxyClientSocketPool(
    int max_sockets,
    int max_sockets_per_group,
    TransportClientSocketPool* transport_pool,
    SSLClientSocketPool* ssl_pool,
    NetLog* net_log)
    : transport_pool_(transport_pool),
      ssl_pool_(ssl_pool),
      base_(this,
            max_sockets,
            max_sockets_per_group,
            ClientSocketPool::unused_idle_socket_timeout(),
            ClientSocketPool::used_idle_socket_timeout(),
            new HttpProxyConnectJobFactory(transport_pool, ssl_pool, net_log)) {
  // We should always have a |transport_pool_| except in unit tests.
  if (transport_pool_)
    base_.AddLowerLayeredPool(transport_pool_);
  if (ssl_pool_)
    base_.AddLowerLayeredPool(ssl_pool_);
}

HttpProxyClientSocketPool::~HttpProxyClientSocketPool() {
}

int HttpProxyClientSocketPool::RequestSocket(
    const std::string& group_name, const void* socket_params,
    RequestPriority priority, ClientSocketHandle* handle,
    const CompletionCallback& callback, const BoundNetLog& net_log) {
  const scoped_refptr<HttpProxySocketParams>* casted_socket_params =
      static_cast<const scoped_refptr<HttpProxySocketParams>*>(socket_params);

  return base_.RequestSocket(group_name, *casted_socket_params, priority,
                             handle, callback, net_log);
}

void HttpProxyClientSocketPool::RequestSockets(
    const std::string& group_name,
    const void* params,
    int num_sockets,
    const BoundNetLog& net_log) {
  const scoped_refptr<HttpProxySocketParams>* casted_params =
      static_cast<const scoped_refptr<HttpProxySocketParams>*>(params);

  base_.RequestSockets(group_name, *casted_params, num_sockets, net_log);
}

void HttpProxyClientSocketPool::CancelRequest(
    const std::string& group_name,
    ClientSocketHandle* handle) {
  base_.CancelRequest(group_name, handle);
}

void HttpProxyClientSocketPool::ReleaseSocket(const std::string& group_name,
                                              scoped_ptr<StreamSocket> socket,
                                              int id) {
  base_.ReleaseSocket(group_name, socket.Pass(), id);
}

void HttpProxyClientSocketPool::FlushWithError(int error) {
  base_.FlushWithError(error);
}

void HttpProxyClientSocketPool::CloseIdleSockets() {
  base_.CloseIdleSockets();
}

int HttpProxyClientSocketPool::IdleSocketCount() const {
  return base_.idle_socket_count();
}

int HttpProxyClientSocketPool::IdleSocketCountInGroup(
    const std::string& group_name) const {
  return base_.IdleSocketCountInGroup(group_name);
}

LoadState HttpProxyClientSocketPool::GetLoadState(
    const std::string& group_name, const ClientSocketHandle* handle) const {
  return base_.GetLoadState(group_name, handle);
}

scoped_ptr<base::DictionaryValue> HttpProxyClientSocketPool::GetInfoAsValue(
    const std::string& name,
    const std::string& type,
    bool include_nested_pools) const {
  scoped_ptr<base::DictionaryValue> dict(base_.GetInfoAsValue(name, type));
  if (include_nested_pools) {
    base::ListValue* list = new base::ListValue();
    if (transport_pool_) {
      list->Append(transport_pool_->GetInfoAsValue("transport_socket_pool",
                                                   "transport_socket_pool",
                                                   true));
    }
    if (ssl_pool_) {
      list->Append(ssl_pool_->GetInfoAsValue("ssl_socket_pool",
                                             "ssl_socket_pool",
                                             true));
    }
    dict->Set("nested_pools", list);
  }
  return dict.Pass();
}

base::TimeDelta HttpProxyClientSocketPool::ConnectionTimeout() const {
  return base_.ConnectionTimeout();
}

bool HttpProxyClientSocketPool::IsStalled() const {
  return base_.IsStalled();
}

void HttpProxyClientSocketPool::AddHigherLayeredPool(
    HigherLayeredPool* higher_pool) {
  base_.AddHigherLayeredPool(higher_pool);
}

void HttpProxyClientSocketPool::RemoveHigherLayeredPool(
    HigherLayeredPool* higher_pool) {
  base_.RemoveHigherLayeredPool(higher_pool);
}

bool HttpProxyClientSocketPool::CloseOneIdleConnection() {
  if (base_.CloseOneIdleSocket())
    return true;
  return base_.CloseOneIdleConnectionInHigherLayeredPool();
}

}  // namespace net