Identity API: web-based scope approval dialogs for getAuthToken

chrome/browser/extensions/api/identity/gaia_web_auth_flow.cc

+// Copyright (c) 2013 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 "chrome/browser/extensions/api/identity/gaia_web_auth_flow.h"
+
+#include "base/string_util.h"
+#include "base/stringprintf.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_split.h"
+#include "google_apis/gaia/gaia_urls.h"
+#include "net/base/escape.h"
+
+namespace extensions {
+
+GaiaWebAuthFlow::GaiaWebAuthFlow(Delegate* delegate,
+                                 Profile* profile,
+                                 chrome::HostDesktopType host_desktop_type,
+                                 const std::string& extension_id,
+                                 const OAuth2Info& oauth2_info)
+    : delegate_(delegate),
+      profile_(profile),
+      host_desktop_type_(host_desktop_type) {
+  const char kOAuth2RedirectPathFormat[] = "/%s#";
+  const char kOAuth2AuthorizeFormat[] =
+      "%s?response_type=token&approval_prompt=force&authuser=0&"
+      "client_id=%s&"
+      "scope=%s&"
+      "origin=chrome-extension://%s/&"
+      "redirect_uri=%s:/%s";
+
+  std::vector<std::string> client_id_parts;
+  base::SplitString(oauth2_info.client_id, '.', &client_id_parts);
+  std::reverse(client_id_parts.begin(), client_id_parts.end());
+  redirect_scheme_ = JoinString(client_id_parts, '.');
+
+  redirect_path_prefix_ =
+      base::StringPrintf(kOAuth2RedirectPathFormat, extension_id.c_str());
+
+  auth_url_ = base::StringPrintf(
+      kOAuth2AuthorizeFormat,
+      GaiaUrls::GetInstance()->oauth2_auth_url().c_str(),
+      oauth2_info.client_id.c_str(),
+      net::EscapeUrlEncodedData(JoinString(oauth2_info.scopes, ' '), true)
+          .c_str(),
+      extension_id.c_str(),
+      redirect_scheme_.c_str(),
+      extension_id.c_str());
+}
+
+GaiaWebAuthFlow::~GaiaWebAuthFlow() {}
+
+void GaiaWebAuthFlow::Start() {
+  ubertoken_fetcher_.reset(new UbertokenFetcher(profile_, this));
+  ubertoken_fetcher_->StartFetchingToken();
+}
+
+void GaiaWebAuthFlow::OnUbertokenSuccess(const std::string& token) {
+  const char kMergeSessionQueryFormat[] = "?uberauth=%s&"
+                                          "continue=%s&"
+                                          "source=appsv2";
+
+  std::string merge_query =
+      base::StringPrintf(kMergeSessionQueryFormat,
+                         net::EscapeUrlEncodedData(token, true).c_str(),
+                         net::EscapeUrlEncodedData(auth_url_, true).c_str());
+  GURL merge_url(GaiaUrls::GetInstance()->merge_session_url() + merge_query);
+
+  web_flow_ = CreateWebAuthFlow(merge_url);
+  web_flow_->Start();
+}
+
+void GaiaWebAuthFlow::OnUbertokenFailure(const GoogleServiceAuthError& error) {
+  delegate_->OnGaiaFlowFailure(GaiaWebAuthFlow::SERVICE_AUTH_ERROR, error);
+}
+
+void GaiaWebAuthFlow::OnAuthFlowFailure(WebAuthFlow::Failure failure) {
+  DCHECK(failure == WebAuthFlow::WINDOW_CLOSED);
+  delegate_->OnGaiaFlowFailure(
+      GaiaWebAuthFlow::WINDOW_CLOSED,
+      GoogleServiceAuthError(GoogleServiceAuthError::NONE));
+}
+
+void GaiaWebAuthFlow::OnAuthFlowURLChange(const GURL& url) {
+  const char kOAuth2RedirectAccessTokenKey[] = "access_token";
+  const char kOAuth2RedirectErrorKey[] = "error";
+  const char kOAuth2ExpiresInKey[] = "expires_in";
+
+  // The format of the target URL is:
+  //     reversed.oauth.client.id:/extensionid#access_token=TOKEN
+  //
+  // Because there is no double slash, everything after the scheme is
+  // interpreted as a path, including the fragment.
+
+  if (url.scheme() == redirect_scheme_ && !url.has_host() && !url.has_port() &&
+      StartsWithASCII(url.path(), redirect_path_prefix_, true)) {
+    web_flow_.reset();
+
+    std::string fragment =
+        url.path().substr(redirect_path_prefix_.length(), std::string::npos);
+    std::vector<std::pair<std::string, std::string> > pairs;
+    base::SplitStringIntoKeyValuePairs(fragment, '=', '&', &pairs);
+    std::string access_token;
+    std::string error;
+    std::string expiration;
+
+    for (std::vector<std::pair<std::string, std::string> >::iterator
+             it = pairs.begin();
+         it != pairs.end();
+         ++it) {
+      if (it->first == kOAuth2RedirectAccessTokenKey)
+        access_token = it->second;
+      else if (it->first == kOAuth2RedirectErrorKey)
+        error = it->second;
+      else if (it->first == kOAuth2ExpiresInKey)
+        expiration = it->second;
+    }
+
+    if (access_token.empty() && error.empty()) {
+      delegate_->OnGaiaFlowFailure(
+          GaiaWebAuthFlow::INVALID_REDIRECT,
+          GoogleServiceAuthError(GoogleServiceAuthError::NONE));
+    } else {
+      delegate_->OnGaiaFlowCompleted(access_token, expiration, error);
+    }
+  }
+}
+
+void GaiaWebAuthFlow::OnAuthFlowTitleChange(const std::string& title) {
+  // On the final page the title will be "Loading <redirect-url>".
+  // Treat it as though we'd really been redirected to <redirect-url>.
+  const char kRedirectPrefix[] = "Loading ";
+  std::string prefix(kRedirectPrefix);
+
+  if (StartsWithASCII(title, prefix, true)) {
+    GURL url(title.substr(prefix.length(), std::string::npos));
+    if (url.is_valid())
+      OnAuthFlowURLChange(url);
+  }
+}
+
+scoped_ptr<WebAuthFlow> GaiaWebAuthFlow::CreateWebAuthFlow(GURL url) {
+  gfx::Rect initial_bounds;
+  return scoped_ptr<WebAuthFlow>(new WebAuthFlow(this,
+                                                 profile_,
+                                                 url,
+                                                 WebAuthFlow::INTERACTIVE,
+                                                 initial_bounds,
+                                                 host_desktop_type_));
+}
+
+}  // extensions