Added DtlsCertificate, a ref counted object owning an SSLIdentity

talk/app/webrtc/statscollector.cc

 /*
  * libjingle
  * Copyright 2012 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 682 matching lines @@
     // same local and remote certificates.
     //
     // Note that Transport::GetIdentity and Transport::GetRemoteCertificate
     // invoke method calls on the worker thread and block this thread, but
     // messages are still processed on this thread, which may blow way the
     // existing transports. So we cannot reuse |transport| after these calls.
     StatsReport::Id local_cert_report_id, remote_cert_report_id;
 
     cricket::Transport* transport =
         session_->GetTransport(transport_iter.second.content_name);
-    rtc::scoped_ptr<rtc::SSLIdentity> identity;
-    if (transport && transport->GetIdentity(identity.accept())) {
-      StatsReport* r = AddCertificateReports(&(identity->certificate()));
+    rtc::scoped_refptr<webrtc::DtlsCertificate> dtlscert;
+    if (transport && transport->GetCertificate(&dtlscert)) {
+      StatsReport* r = AddCertificateReports(
+          &(dtlscert->identity()->certificate()));

[Henrik Grunell WebRTC, 2015/08/12 14:46:29]

This is confusing. What's the cert we get from the identity? Obviously not the
|dtlscert|.

[hbos, 2015/08/14 14:09:39]

Yeah, two things called certificate is confusing... Not sure what the best way
is around it though. Perhaps there is a better name than DtlsCertificate or
perhaps certificate() could be called sslcertificate() but I would like to
minimize name changes in this already enormous CL. Hmmm...

SSLIdentity::certificate() gets an SSLCertificate which is a lower level concept
of a certificate (an abstract interface for "wrapping the SSL library's notion
of a certificate", it has various implementations just like there are various
SSLIdentity implementations). The specific implementations of SSLIdentity and
SSLCertificate interact with specific crypto libraries.
This goes to crypto stuff I don't understand.

The DtlsCertificate is a higher level concept of a certificate that just points
to the lower level stuff and is reference counted, not concerned about how the
crypto stuff works. It should be analogous to the RTCCertificate that the
specifications talk about. Something that can be passed around and which
specifies which underlying crypto magic to use.

[Henrik Grunell WebRTC, 2015/08/18 14:25:11]

OK. If this is clear in the DtlsCertificate class description (in its header), I
think it's fine.

       if (r)
         local_cert_report_id = r->id();
     }
 
     transport = session_->GetTransport(transport_iter.second.content_name);
     rtc::scoped_ptr<rtc::SSLCertificate> cert;
     if (transport && transport->GetRemoteCertificate(cert.accept())) {
       StatsReport* r = AddCertificateReports(cert.get());
       if (r)
         remote_cert_report_id = r->id();
@@ skipping 219 matching lines @@
     report->set_timestamp(stats_gathering_started_);
   }
 
 }
 
 void StatsCollector::ClearUpdateStatsCacheForTest() {
   stats_gathering_started_ = 0;
 }
 
 }  // namespace webrtc