// Copyright (c) 2011 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 "ppapi/shared_impl/url_request_info_impl.h"

#include "base/string_util.h"
#include "ppapi/shared_impl/var.h"
#include "ppapi/thunk/enter.h"
#include "ppapi/thunk/ppb_file_ref_api.h"

using ppapi::thunk::EnterResourceNoLock;

namespace ppapi {

namespace {

const int32_t kDefaultPrefetchBufferUpperThreshold = 100 * 1000 * 1000;
const int32_t kDefaultPrefetchBufferLowerThreshold = 50 * 1000 * 1000;

// These methods are not allowed by the XMLHttpRequest standard.
// http://www.w3.org/TR/XMLHttpRequest/#the-open-method
const char* const kForbiddenHttpMethods[] = {
  "connect",
  "trace",
  "track",
};

// These are the "known" methods in the Webkit XHR implementation. Also see
// the XMLHttpRequest standard.
// http://www.w3.org/TR/XMLHttpRequest/#the-open-method
const char* const kKnownHttpMethods[] = {
  "get",
  "post",
  "put",
  "head",
  "copy",
  "delete",
  "index",
  "lock",
  "m-post",
  "mkcol",
  "move",
  "options",
  "propfind",
  "proppatch",
  "unlock",
};

bool IsValidToken(const std::string& token) {
  size_t length = token.size();
  if (length == 0)
    return false;

  for (size_t i = 0; i < length; i++) {
    char c = token[i];
    if (c >= 127 || c <= 32)
      return false;
    if (c == '(' || c == ')' || c == '<' || c == '>' || c == '@' ||
        c == ',' || c == ';' || c == ':' || c == '\\' || c == '\"' ||
        c == '/' || c == '[' || c == ']' || c == '?' || c == '=' ||
        c == '{' || c == '}')
      return false;
  }
  return true;
}

}  // namespace

PPB_URLRequestInfo_Data::BodyItem::BodyItem()
    : is_file(false),
      start_offset(0),
      number_of_bytes(-1),
      expected_last_modified_time(0.0) {
}

PPB_URLRequestInfo_Data::BodyItem::BodyItem(const std::string& data)
    : is_file(false),
      data(data),
      start_offset(0),
      number_of_bytes(-1),
      expected_last_modified_time(0.0) {
}

PPB_URLRequestInfo_Data::BodyItem::BodyItem(
    Resource* file_ref,
    int64_t start_offset,
    int64_t number_of_bytes,
    PP_Time expected_last_modified_time)
    : is_file(true),
      file_ref(file_ref),
      file_ref_host_resource(file_ref->host_resource()),
      start_offset(start_offset),
      number_of_bytes(number_of_bytes),
      expected_last_modified_time(expected_last_modified_time) {
}

PPB_URLRequestInfo_Data::PPB_URLRequestInfo_Data()
    : url(),
      method(),
      headers(),
      stream_to_file(false),
      follow_redirects(true),
      record_download_progress(false),
      record_upload_progress(false),
      has_custom_referrer_url(false),
      custom_referrer_url(),
      allow_cross_origin_requests(false),
      allow_credentials(false),
      has_custom_content_transfer_encoding(false),
      custom_content_transfer_encoding(),
      prefetch_buffer_upper_threshold(kDefaultPrefetchBufferUpperThreshold),
      prefetch_buffer_lower_threshold(kDefaultPrefetchBufferLowerThreshold),
      body() {
}

PPB_URLRequestInfo_Data::~PPB_URLRequestInfo_Data() {
}

URLRequestInfoImpl::URLRequestInfoImpl(PP_Instance instance,
                                       const PPB_URLRequestInfo_Data& data)
    : Resource(instance),
      data_(data) {
}

URLRequestInfoImpl::URLRequestInfoImpl(const HostResource& host_resource,
                                       const PPB_URLRequestInfo_Data& data)
    : Resource(host_resource),
      data_(data) {
}

URLRequestInfoImpl::~URLRequestInfoImpl() {
}

thunk::PPB_URLRequestInfo_API* URLRequestInfoImpl::AsPPB_URLRequestInfo_API() {
  return this;
}

PP_Bool URLRequestInfoImpl::SetProperty(PP_URLRequestProperty property,
                                        PP_Var var) {
  // IMPORTANT: Do not do security validation of parameters at this level
  // without also adding them to PPB_URLRequestInfo_Impl::ValidateData. This
  // code is used both in the plugin (which we don't trust) and in the renderer
  // (which we trust more). When running out-of-process, the plugin calls this
  // function to configure the PPB_URLRequestInfo_Data, which is then sent to
  // the renderer and *not* run through SetProperty again.
  //
  // This means that anything in the PPB_URLRequestInfo_Data needs to be
  // validated at the time the URL is requested (which is what ValidateData
  // does). If your feature requires security checks, it should be in the
  // implementation in the renderer when the WebKit request is actually
  // constructed.
  //
  // It is legal to do some validation here if you want to report failure to
  // the plugin as a convenience, as long as you also do it in the renderer
  // later.
  PP_Bool result = PP_FALSE;
  switch (var.type) {
    case PP_VARTYPE_UNDEFINED:
      result = PP_FromBool(SetUndefinedProperty(property));
      break;
    case PP_VARTYPE_BOOL:
      result = PP_FromBool(
          SetBooleanProperty(property, PP_ToBool(var.value.as_bool)));
      break;
    case PP_VARTYPE_INT32:
      result = PP_FromBool(
          SetIntegerProperty(property, var.value.as_int));
      break;
    case PP_VARTYPE_STRING: {
      StringVar* string = StringVar::FromPPVar(var);
      if (string)
        result = PP_FromBool(SetStringProperty(property, string->value()));
      break;
    }
    default:
      break;
  }
  return result;
}

PP_Bool URLRequestInfoImpl::AppendDataToBody(const void* data, uint32_t len) {
  if (len > 0) {
    data_.body.push_back(PPB_URLRequestInfo_Data::BodyItem(
        std::string(static_cast<const char*>(data), len)));
  }
  return PP_TRUE;
}

PP_Bool URLRequestInfoImpl::AppendFileToBody(
    PP_Resource file_ref,
    int64_t start_offset,
    int64_t number_of_bytes,
    PP_Time expected_last_modified_time) {
  EnterResourceNoLock<thunk::PPB_FileRef_API> enter(file_ref, true);
  if (enter.failed())
    return PP_FALSE;

  // Ignore a call to append nothing.
  if (number_of_bytes == 0)
    return PP_TRUE;

  // Check for bad values.  (-1 means read until end of file.)
  if (start_offset < 0 || number_of_bytes < -1)
    return PP_FALSE;

  data_.body.push_back(PPB_URLRequestInfo_Data::BodyItem(
      enter.resource(),
      start_offset,
      number_of_bytes,
      expected_last_modified_time));
  return PP_TRUE;
}

const PPB_URLRequestInfo_Data& URLRequestInfoImpl::GetData() const {
  return data_;
}

// static
std::string URLRequestInfoImpl::ValidateMethod(const std::string& method) {
  if (!IsValidToken(method))
    return std::string();

  for (size_t i = 0; i < arraysize(kForbiddenHttpMethods); ++i) {
    if (LowerCaseEqualsASCII(method, kForbiddenHttpMethods[i]))
      return std::string();
  }
  for (size_t i = 0; i < arraysize(kKnownHttpMethods); ++i) {
    if (LowerCaseEqualsASCII(method, kKnownHttpMethods[i])) {
      // Convert the method name to upper case to match Webkit and Firefox's
      // XHR implementation.
      return StringToUpperASCII(std::string(kKnownHttpMethods[i]));
    }
  }
  // Pass through unknown methods that are not forbidden.
  return method;
}

bool URLRequestInfoImpl::SetUndefinedProperty(PP_URLRequestProperty property) {
  // IMPORTANT: Do not do security validation of parameters at this level
  // without also adding them to PPB_URLRequestInfo_Impl::ValidateData. See
  // SetProperty() above for why.
  switch (property) {
    case PP_URLREQUESTPROPERTY_CUSTOMREFERRERURL:
      data_.has_custom_referrer_url = false;
      data_.custom_referrer_url = std::string();
      return true;
    case PP_URLREQUESTPROPERTY_CUSTOMCONTENTTRANSFERENCODING:
      data_.has_custom_content_transfer_encoding = false;
      data_.custom_content_transfer_encoding = std::string();
      return true;
    default:
      return false;
  }
}

bool URLRequestInfoImpl::SetBooleanProperty(PP_URLRequestProperty property,
                                            bool value) {
  // IMPORTANT: Do not do security validation of parameters at this level
  // without also adding them to PPB_URLRequestInfo_Impl::ValidateData. See
  // SetProperty() above for why.
  switch (property) {
    case PP_URLREQUESTPROPERTY_STREAMTOFILE:
      data_.stream_to_file = value;
      return true;
    case PP_URLREQUESTPROPERTY_FOLLOWREDIRECTS:
      data_.follow_redirects = value;
      return true;
    case PP_URLREQUESTPROPERTY_RECORDDOWNLOADPROGRESS:
      data_.record_download_progress = value;
      return true;
    case PP_URLREQUESTPROPERTY_RECORDUPLOADPROGRESS:
      data_.record_upload_progress = value;
      return true;
    case PP_URLREQUESTPROPERTY_ALLOWCROSSORIGINREQUESTS:
      data_.allow_cross_origin_requests = value;
      return true;
    case PP_URLREQUESTPROPERTY_ALLOWCREDENTIALS:
      data_.allow_credentials = value;
      return true;
    default:
      return false;
  }
}

bool URLRequestInfoImpl::SetIntegerProperty(PP_URLRequestProperty property,
                                            int32_t value) {
  // IMPORTANT: Do not do security validation of parameters at this level
  // without also adding them to PPB_URLRequestInfo_Impl::ValidateData. See
  // SetProperty() above for why.
  switch (property) {
    case PP_URLREQUESTPROPERTY_PREFETCHBUFFERUPPERTHRESHOLD:
      data_.prefetch_buffer_upper_threshold = value;
      return true;
    case PP_URLREQUESTPROPERTY_PREFETCHBUFFERLOWERTHRESHOLD:
      data_.prefetch_buffer_lower_threshold = value;
      return true;
    default:
      return false;
  }
}

bool URLRequestInfoImpl::SetStringProperty(PP_URLRequestProperty property,
                                           const std::string& value) {
  // IMPORTANT: Do not do security validation of parameters at this level
  // without also adding them to PPB_URLRequestInfo_Impl::ValidateData. See
  // SetProperty() above for why.
  switch (property) {
    case PP_URLREQUESTPROPERTY_URL:
      data_.url = value;  // NOTE: This may be a relative URL.
      return true;
    case PP_URLREQUESTPROPERTY_METHOD: {
      // Convenience check for synchronously returning errors to the plugin.
      // This is re-checked in ValidateData.
      std::string canonicalized = ValidateMethod(value);
      if (canonicalized.empty())
        return false;
      data_.method = canonicalized;
      return true;
    }
    case PP_URLREQUESTPROPERTY_HEADERS:
      data_.headers = value;
      return true;
    case PP_URLREQUESTPROPERTY_CUSTOMREFERRERURL:
      data_.has_custom_referrer_url = true;
      data_.custom_referrer_url = value;
      return true;
    case PP_URLREQUESTPROPERTY_CUSTOMCONTENTTRANSFERENCODING:
      data_.has_custom_content_transfer_encoding = true;
      data_.custom_content_transfer_encoding = value;
      return true;
    default:
      return false;
  }
}

}  // namespace ppapi