Fix subtle dynamic library loading problem and deflake the tree.

shell/application_manager/network_fetcher.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 "shell/application_manager/network_fetcher.h"
 
 #include "base/bind.h"
 #include "base/files/file.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
@@ skipping 69 matching lines @@
       base::StringPrintf("%s %s\n", path.value().c_str(), url.spec().c_str());
   // TODO(eseidel): AppendToFile is missing O_CREAT, crbug.com/450696
   if (!PathExists(map_path))
     base::WriteFile(map_path, map_entry.data(), map_entry.length());
   else
     base::AppendToFile(map_path, map_entry.data(), map_entry.length());
 }
 
 // AppIds should be be both predictable and unique, but any hash would work.
 // Currently we use sha256 from crypto/secure_hash.h
-bool NetworkFetcher::ComputeAppId(const base::FilePath& path,
+bool NetworkFetcher::ComputeAppId(const GURL& canonical_url,
+                                  const base::FilePath& path,
                                   std::string* digest_string) {
   scoped_ptr<crypto::SecureHash> ctx(
       crypto::SecureHash::Create(crypto::SecureHash::SHA256));
   base::File file(path, base::File::FLAG_OPEN | base::File::FLAG_READ);
   if (!file.IsValid()) {
     LOG(ERROR) << "Failed to open " << path.value() << " for computing AppId";
     return false;
   }
+  std::string spec = canonical_url.spec();
+  uint32_t len = static_cast<uint32_t>(spec.size());
+  // Prevent URL vs. content spoofing.
+  ctx->Update(&len, sizeof(len));
+  ctx->Update(spec.c_str(), spec.size());
   char buf[1024];
   while (file.IsValid()) {
     int bytes_read = file.ReadAtCurrentPos(buf, sizeof(buf));
     if (bytes_read == 0)
       break;
     ctx->Update(buf, bytes_read);
   }
   if (!file.IsValid()) {
     LOG(ERROR) << "Error reading " << path.value();
     return false;
   }
   // The output is really a vector of unit8, we're cheating by using a string.
   std::string output(crypto::kSHA256Length, 0);
   ctx->Finish(string_as_array(&output), output.size());
   output = base::HexEncode(output.c_str(), output.size());
   // Using lowercase for compatiblity with sha256sum output.
   *digest_string = base::StringToLowerASCII(output);
   return true;
 }
 
-bool NetworkFetcher::RenameToAppId(const base::FilePath& old_path,
+bool NetworkFetcher::RenameToAppId(const GURL& canonical_url,
+                                   const base::FilePath& old_path,
                                    base::FilePath* new_path) {
   std::string app_id;
-  if (!ComputeAppId(old_path, &app_id))
+  if (!ComputeAppId(canonical_url, old_path, &app_id))
     return false;
 
   base::FilePath temp_dir;
   base::GetTempDir(&temp_dir);
   std::string unique_name = base::StringPrintf("%s.mojo", app_id.c_str());
   *new_path = temp_dir.Append(unique_name);
   return base::Move(old_path, *new_path);
 }
 
 void NetworkFetcher::CopyCompleted(
     base::Callback<void(const base::FilePath&, bool)> callback,
     bool success) {
   // The copy completed, now move to $TMP/$APP_ID.mojo before the dlopen.
   if (success) {
     success = false;
     base::FilePath new_path;
-    if (RenameToAppId(path_, &new_path)) {
+    if (RenameToAppId(GURL(response_->url), path_, &new_path)) {
       if (base::PathExists(new_path)) {
         path_ = new_path;
         success = true;
         RecordCacheToURLMapping(path_, url_);
       }
     }
   }
 
   base::MessageLoop::current()->PostTask(FROM_HERE,
                                          base::Bind(callback, path_, success));
@@ skipping 59 matching lines @@
     loader_callback_.Run(make_scoped_ptr<Fetcher>(NULL));
     return;
   }
 
   response_ = response.Pass();
   loader_callback_.Run(make_scoped_ptr(this));
 }
 
 }  // namespace shell
 }  // namespace mojo