Implementation for chrome.certificateProvider.requestPin/stopPinRequest

chrome/browser/chromeos/certificate_provider/sign_requests.cc

 // Copyright 2015 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/chromeos/certificate_provider/sign_requests.h"
 
 #include "base/callback.h"
+#include "base/rand_util.h"
 
 namespace chromeos {
 namespace certificate_provider {
 
 SignRequests::RequestsState::RequestsState() {}
 
 SignRequests::RequestsState::RequestsState(const RequestsState& other) =
     default;
 
 SignRequests::RequestsState::~RequestsState() {}
 
 SignRequests::SignRequests() {}
 
 SignRequests::~SignRequests() {}
 
 int SignRequests::AddRequest(const std::string& extension_id,
                              const net::SSLPrivateKey::SignCallback& callback) {
   RequestsState& state = extension_to_requests_[extension_id];
-  const int request_id = state.next_free_id++;
+  // Generate a random request id so that extensions using
+  // chrome.certificateProvider can not guess another extension's request id.
+  int request_id = base::RandInt(0, INT_MAX);

[emaxx, 2016/09/19 14:01:43]

nit: #include <climits>

+  while (state.pending_requests.find(request_id) !=
+         state.pending_requests.end()) {
+    request_id = base::RandInt(0, INT_MAX);
+  }
   state.pending_requests[request_id] = callback;
   return request_id;
 }
 
 bool SignRequests::RemoveRequest(const std::string& extension_id,
                                  int request_id,
                                  net::SSLPrivateKey::SignCallback* callback) {
   RequestsState& state = extension_to_requests_[extension_id];
   std::map<int, net::SSLPrivateKey::SignCallback>& pending =
       state.pending_requests;
@@ skipping 13 matching lines @@
   for (const auto& entry :
        extension_to_requests_[extension_id].pending_requests) {
     callbacks.push_back(entry.second);
   }
   extension_to_requests_.erase(extension_id);
   return callbacks;
 }
 
 }  // namespace certificate_provider
 }  // namespace chromeos