brave_translate_redirect_network_delegate_helper.cc

/* Copyright (c) 2019 The Brave Authors. All rights reserved.
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "brave/browser/net/brave_translate_redirect_network_delegate_helper.h"

#include <memory>
#include <string>
#include <vector>

#include "brave/common/translate_network_constants.h"
#include "brave/components/translate/core/browser/brave_translate_features.h"
#include "extensions/common/url_pattern.h"
#include "net/base/net_errors.h"

namespace {
const char kTranslateElementLibQuery[] = "client=te_lib";

int OkIfBraveTranslateGoAvailableElseAbort() {
  return translate::IsBraveTranslateGoAvailable() ? net::OK : net::ERR_ABORTED;
}

}  // namespace

namespace brave {

bool IsTranslateScriptRequest(const GURL& gurl) {
  static std::vector<URLPattern> translate_patterns({
      URLPattern(URLPattern::SCHEME_HTTPS, kTranslateElementMainJSPattern),
      URLPattern(URLPattern::SCHEME_HTTPS, kTranslateMainJSPattern),
      });
  return std::any_of(translate_patterns.begin(), translate_patterns.end(),
      [&gurl](URLPattern pattern) {
      return pattern.MatchesURL(gurl);
      });
}

bool IsTranslateResourceRequest(const GURL& gurl) {
  static std::vector<URLPattern> translate_patterns({
      URLPattern(URLPattern::SCHEME_HTTPS, kTranslateElementMainCSSPattern),
      URLPattern(URLPattern::SCHEME_HTTPS, kTranslateBrandingPNGPattern),
      });
  return std::any_of(translate_patterns.begin(), translate_patterns.end(),
      [&gurl](URLPattern pattern) {
      return pattern.MatchesURL(gurl);
      });
}

bool IsTranslateRequest(const GURL& gurl) {
  static URLPattern translate_pattern =
    URLPattern(URLPattern::SCHEME_HTTPS, kTranslateRequestPattern);
  return translate_pattern.MatchesURL(gurl);
}

bool IsTranslateGen204Request(const GURL& gurl) {
  static URLPattern pattern = URLPattern(URLPattern::SCHEME_HTTPS,
      kTranslateGen204Pattern);
  bool is_te_lib =
    gurl.spec().find(kTranslateElementLibQuery) != std::string::npos;

  return is_te_lib && pattern.MatchesURL(gurl);
}

int OnBeforeURLRequest_TranslateRedirectWork(
    const ResponseCallback& next_callback,
    std::shared_ptr<BraveRequestInfo> ctx) {
  GURL::Replacements replacements;

  if (translate::DisableTranslateLibraryNetworkRedirects())
    return net::OK;

  // Skip extensions/service-worker/etc requests.
  if (!ctx->initiator_url.SchemeIsHTTPOrHTTPS())
    return net::OK;

  const static std::string kTranslateInitiatorHost(
      GURL(kTranslateInitiatorURL).host());
  const static std::string kTranslateGen204PatternHost(
      GURL(kTranslateGen204Pattern).host());
  const static std::string kTranslateBrandingPngHost(
      GURL(kTranslateBrandingPNGPattern).host());

  // Fast way to exclude any unrelated requests.
  if (ctx->request_url.host_piece() != kTranslateInitiatorHost ||
      ctx->request_url.host_piece() != kTranslateGen204PatternHost ||
      ctx->request_url.host_piece() != kTranslateBrandingPngHost) {
    return net::OK;
  }

  // Abort those gen204 requests triggered by translate element library.
  if (IsTranslateGen204Request(ctx->request_url)) {
    return net::ERR_ABORTED;
  }

  // For those translate resources which might be triggered by translate
  // element library, go through brave's proxy so we won't introduce direct
  // connection to google when using translate element library.
  if (IsTranslateResourceRequest(ctx->request_url)) {
    replacements.SetPathStr(ctx->request_url.path_piece());
    ctx->new_url_spec =
      GURL(kBraveTranslateEndpoint).ReplaceComponents(replacements).spec();
    return OkIfBraveTranslateGoAvailableElseAbort();
  }

  if (IsTranslateScriptRequest(ctx->request_url)) {
    replacements.SetQueryStr(ctx->request_url.query_piece());
    replacements.SetPathStr(ctx->request_url.path_piece());
    ctx->new_url_spec =
      GURL(kBraveTranslateEndpoint).ReplaceComponents(replacements).spec();
    return OkIfBraveTranslateGoAvailableElseAbort();
  }

  if (IsTranslateRequest(ctx->request_url)) {
    replacements.SetQueryStr(ctx->request_url.query_piece());
    ctx->new_url_spec =
      GURL(kBraveTranslateEndpoint).ReplaceComponents(replacements).spec();
    return OkIfBraveTranslateGoAvailableElseAbort();
  }

  return net::OK;
}

}  // namespace brave