Adding DiskBasedCertCache to HttpCache (+UMA).

net/http/http_cache_transaction.cc

 // Copyright (c) 2012 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 "net/http/http_cache_transaction.h"
 
 #include "build/build_config.h"
 
 #if defined(OS_POSIX)
 #include <unistd.h>
@@ skipping 14 matching lines @@
 #include "base/time/time.h"
 #include "net/base/completion_callback.h"
 #include "net/base/io_buffer.h"
 #include "net/base/load_flags.h"
 #include "net/base/load_timing_info.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_log.h"
 #include "net/base/upload_data_stream.h"
 #include "net/cert/cert_status_flags.h"
 #include "net/disk_cache/disk_cache.h"
+#include "net/http/disk_based_cert_cache.h"
 #include "net/http/http_network_session.h"
 #include "net/http/http_request_info.h"
 #include "net/http/http_response_headers.h"
 #include "net/http/http_transaction.h"
 #include "net/http/http_util.h"
 #include "net/http/partial_data.h"
 #include "net/ssl/ssl_cert_request_info.h"
 #include "net/ssl/ssl_config_service.h"
 
 using base::Time;
 using base::TimeDelta;
 using base::TimeTicks;
 
 namespace {
 
+// Stores data relevant to the statistics of writing and reading entire
+// certificate chains using DiskBasedCertCache. |num_pending_ops| is the number
+// of certificates in the chain that have pending operations in the
+// DiskBasedCertCache. |start_time| is the time that the read and write
+// commands began being issued to the DiskBasedCertCache.
+// TODO(brandonsalmon): Remove this when it is no longer necessary to
+// collect data.
+class SharedChainData : public base::RefCountedThreadSafe<SharedChainData> {

[rvargas (doing something else), 2014/07/09 00:05:39]

ThreadSafe? Do we expect multiple threads to be involved?

+ public:
+  SharedChainData(int num_ops, TimeTicks start)
+      : num_pending_ops(num_ops), start_time(start) {}
+
+  int num_pending_ops;
+  TimeTicks start_time;
+
+ private:
+  friend class base::RefCountedThreadSafe<SharedChainData>;
+  ~SharedChainData() {}
+  DISALLOW_COPY_AND_ASSIGN(SharedChainData);
+};
+
+// Used to obtain a cache entry key for an OSCertHandle.
+// TODO(brandonsalmon): Remove this when cache keys are stored
+// and no longer have to be recomputed to retrieve the OSCertHandle
+// from the disk.
+std::string GetCacheKeyForCert(net::X509Certificate::OSCertHandle cert_handle) {
+  net::SHA1HashValue fingerprint =
+      net::X509Certificate::CalculateFingerprint(cert_handle);
+
+  return "cert:" +
+         base::HexEncode(fingerprint.data, arraysize(fingerprint.data));
+}
+
+// |dist_from_root| indicates the position of the read certificate in the
+// certificate chain, 0 indicating it is the root. |is_leaf| indicates
+// whether or not the read certificate was the leaf of the chain.
+// |shared_chain_data| contains data shared by each certificate in
+// the chain.
+void OnCertReadIOComplete(
+    int dist_from_root,
+    bool is_leaf,
+    const scoped_refptr<SharedChainData>& shared_chain_data,
+    net::X509Certificate::OSCertHandle cert_handle) {
+  // If |num_pending_ops| is one, this was the last pending read operation
+  // for this chain of certificates. The total time used to read the chain
+  // can be calculated by subtracting the starting time from Now().
+  shared_chain_data->num_pending_ops--;
+  if (!shared_chain_data->num_pending_ops) {
+    const TimeDelta read_chain_wait =
+        TimeTicks::Now() - shared_chain_data->start_time;
+    UMA_HISTOGRAM_TIMES("DiskBasedCertCache.ChainReadTime", read_chain_wait);
+  }
+
+  bool success = (cert_handle != NULL);
+  UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.ReadSuccessTotal", success);
+
+  if (is_leaf)
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.ReadSuccessLeaf", success);
+  else if (dist_from_root == 0)
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.ReadSuccessRoot", success);
+  else if (dist_from_root == 1)
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.ReadSuccessInt1", success);
+  else if (dist_from_root == 2)
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.ReadSuccessInt2", success);
+  else
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.ReadSuccessIntN", success);
+}
+
+// |dist_from_root| indicates the position of the written certificate in the
+// certificate chain, 0 indicating it is the root. |is_leaf| indicates
+// whether or not the written certificate was the leaf of the chain.
+// |shared_chain_data| contains data shared by each certificate in
+// the chain.
+void OnCertWriteIOComplete(
+    int dist_from_root,
+    bool is_leaf,
+    const scoped_refptr<SharedChainData>& shared_chain_data,
+    const std::string& key) {
+  // If |num_pending_ops| is one, this was the last pending write operation
+  // for this chain of certificates. The total time used to write the chain
+  // can be calculated by subtracting the starting time from Now().
+  shared_chain_data->num_pending_ops--;
+  if (!shared_chain_data->num_pending_ops) {
+    const TimeDelta write_chain_wait =
+        TimeTicks::Now() - shared_chain_data->start_time;
+    UMA_HISTOGRAM_TIMES("DiskBasedCertCache.ChainWriteTime", write_chain_wait);
+  }
+
+  bool success = !key.empty();
+  UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.WriteSuccessTotal", success);
+
+  if (is_leaf)
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.WriteSuccessLeaf", success);
+  else if (dist_from_root == 0)
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.WriteSuccessRoot", success);
+  else if (dist_from_root == 1)
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.WriteSuccessInt1", success);
+  else if (dist_from_root == 2)
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.WriteSuccessInt2", success);
+  else
+    UMA_HISTOGRAM_BOOLEAN("DiskBasedCertCache.WriteSuccessIntN", success);
+}
+
 // From http://tools.ietf.org/html/draft-ietf-httpbis-p6-cache-21#section-6
 //      a "non-error response" is one with a 2xx (Successful) or 3xx
 //      (Redirection) status code.
 bool NonErrorResponse(int status_code) {
   int status_code_range = status_code / 100;
   return status_code_range == 2 || status_code_range == 3;
 }
 
 // Error codes that will be considered indicative of a page being offline/
 // unreachable for LOAD_FROM_CACHE_IF_OFFLINE.
@@ skipping 1428 matching lines @@
 }
 
 int HttpCache::Transaction::DoCacheReadResponseComplete(int result) {
   net_log_.EndEventWithNetErrorCode(NetLog::TYPE_HTTP_CACHE_READ_INFO, result);
   if (result != io_buf_len_ ||
       !HttpCache::ParseResponseInfo(read_buf_->data(), io_buf_len_,
                                     &response_, &truncated_)) {
     return OnCacheReadError(result, true);
   }
 
+  // cert_cache() will be null if the CertCacheTrial field trial is disabled.
+  if (cache_->cert_cache() && response_.ssl_info.is_valid()) {
+    std::string key =

[rvargas (doing something else), 2014/07/09 00:05:39]

This block looks fairly self contained to me. Do you mind creating a dedicated
method?

+        GetCacheKeyForCert(response_.ssl_info.cert->os_cert_handle());
+    const X509Certificate::OSCertHandles& intermediates =
+        response_.ssl_info.cert->GetIntermediateCertificates();
+    int dist_from_root = intermediates.size();
+
+    scoped_refptr<SharedChainData> shared_chain_data(
+        new SharedChainData(intermediates.size() + 1, TimeTicks::Now()));
+    cache_->cert_cache()->Get(key,
+                              base::Bind(&OnCertReadIOComplete,
+                                         dist_from_root,
+                                         true /* is leaf */,
+                                         shared_chain_data));
+
+    for (X509Certificate::OSCertHandles::const_iterator it =
+             intermediates.begin();
+         it != intermediates.end();
+         ++it) {
+      --dist_from_root;
+      key = GetCacheKeyForCert(*it);
+      cache_->cert_cache()->Get(key,
+                                base::Bind(&OnCertReadIOComplete,
+                                           dist_from_root,
+                                           false /* is not leaf */,
+                                           shared_chain_data));
+    }
+    DCHECK_EQ(0, dist_from_root);
+  }
+
   // Some resources may have slipped in as truncated when they're not.
   int current_size = entry_->disk_entry->GetDataSize(kResponseContentIndex);
   if (response_.headers->GetContentLength() == current_size)
     truncated_ = false;
 
   // We now have access to the cache entry.
   //
   //  o if we are a reader for the transaction, then we can start reading the
   //    cache entry.
   //
@@ skipping 812 matching lines @@
   // reverse-map the cert status to a net error and replay the net error.
   if ((cache_->mode() != RECORD &&
        response_.headers->HasHeaderValue("cache-control", "no-store")) ||
       net::IsCertStatusError(response_.ssl_info.cert_status)) {
     DoneWritingToEntry(false);
     if (net_log_.IsLogging())
       net_log_.EndEvent(NetLog::TYPE_HTTP_CACHE_WRITE_INFO);
     return OK;
   }
 
+  // cert_cache() will be null if the CertCacheTrial field trial is disabled.
+  if (cache_->cert_cache() && response_.ssl_info.is_valid()) {
+    const X509Certificate::OSCertHandles& intermediates =

[rvargas (doing something else), 2014/07/09 00:05:39]

same here

+        response_.ssl_info.cert->GetIntermediateCertificates();
+    int dist_from_root = intermediates.size();
+
+    scoped_refptr<SharedChainData> shared_chain_data(
+        new SharedChainData(intermediates.size() + 1, TimeTicks::Now()));
+    cache_->cert_cache()->Set(response_.ssl_info.cert->os_cert_handle(),
+                              base::Bind(&OnCertWriteIOComplete,
+                                         dist_from_root,
+                                         true /* is leaf */,
+                                         shared_chain_data));
+    for (X509Certificate::OSCertHandles::const_iterator it =
+             intermediates.begin();
+         it != intermediates.end();
+         ++it) {
+      --dist_from_root;
+      cache_->cert_cache()->Set(*it,
+                                base::Bind(&OnCertWriteIOComplete,
+                                           dist_from_root,
+                                           false /* is not leaf */,
+                                           shared_chain_data));
+    }
+    DCHECK_EQ(0, dist_from_root);
+  }
+
   // When writing headers, we normally only write the non-transient
   // headers; when in record mode, record everything.
   bool skip_transient_headers = (cache_->mode() != RECORD);
 
   if (truncated)
     DCHECK_EQ(200, response_.headers->response_code());
 
   scoped_refptr<PickledIOBuffer> data(new PickledIOBuffer());
   response_.Persist(data->pickle(), skip_transient_headers, truncated);
   data->Done();
@@ skipping 236 matching lines @@
     default:
       NOTREACHED();
   }
 }
 
 void HttpCache::Transaction::OnIOComplete(int result) {
   DoLoop(result);
 }
 
 }  // namespace net