Enable Certificate Transparency in the OpenSSL port.

net/socket/ssl_client_socket_openssl.cc

Index: net/socket/ssl_client_socket_openssl.cc
diff --git a/net/socket/ssl_client_socket_openssl.cc b/net/socket/ssl_client_socket_openssl.cc
index f7b9d28d2442338ef490f643ac0dd99edf95efc7..214f7d437051df11585ecb5e4c49a68a5e2e5db6 100644
--- a/net/socket/ssl_client_socket_openssl.cc
+++ b/net/socket/ssl_client_socket_openssl.cc
@@ -21,6 +21,7 @@
 #include "crypto/scoped_openssl_types.h"
 #include "net/base/net_errors.h"
 #include "net/cert/cert_verifier.h"
+#include "net/cert/ct_verifier.h"
 #include "net/cert/single_request_cert_verifier.h"
 #include "net/cert/x509_certificate_net_log_param.h"
 #include "net/http/transport_security_state.h"
@@ -346,6 +347,7 @@ SSLClientSocketOpenSSL::SSLClientSocketOpenSSL(
       was_ever_used_(false),
       client_auth_cert_needed_(false),
       cert_verifier_(context.cert_verifier),
+      cert_transparency_verifier_(context.cert_transparency_verifier),
       channel_id_service_(context.channel_id_service),
       ssl_(NULL),
       transport_bio_(NULL),
@@ -599,6 +601,8 @@ bool SSLClientSocketOpenSSL::GetSSLInfo(SSLInfo* ssl_info) {
   ssl_info->channel_id_sent = WasChannelIDSent();
   ssl_info->pinning_failure_log = pinning_failure_log_;
 
+  AddSCTInfoToSSLInfo(ssl_info);
+
   const SSL_CIPHER* cipher = SSL_get_current_cipher(ssl_);
   CHECK(cipher);
   ssl_info->security_bits = SSL_CIPHER_get_bits(cipher, NULL);
@@ -808,6 +812,14 @@ int SSLClientSocketOpenSSL::Init() {
                         wire_protos.size());
   }
 
+  if (ssl_config_.signed_cert_timestamps_enabled) {
+    SSL_enable_signed_cert_timestamps(ssl_);
+    SSL_enable_ocsp_stapling(ssl_);
+  }
+
+  // TODO(davidben): Enable OCSP stapling on platforms which support it and pass
+  // into the certificate verifier.

[Ryan Sleevi, 2014/09/02 19:49:06]

nit: BUG #?

[davidben, 2014/09/02 22:13:45]

Done.

+
   return OK;
 }
 
@@ -903,6 +915,16 @@ int SSLClientSocketOpenSSL::DoHandshake() {
                            ssl_config_.channel_id_enabled,
                            crypto::ECPrivateKey::IsSupported());
 
+    uint8_t* ocsp_response;
+    size_t ocsp_response_len;
+    SSL_get0_ocsp_response(ssl_, &ocsp_response, &ocsp_response_len);
+    set_stapled_ocsp_response_received(ocsp_response_len != 0);
+
+    uint8_t* sct_list;
+    size_t sct_list_len;
+    SSL_get0_signed_cert_timestamp_list(ssl_, &sct_list, &sct_list_len);
+    set_signed_cert_timestamps_received(sct_list_len != 0);
+
     // Verify the certificate.
     const bool got_cert = !!UpdateServerCert();
     DCHECK(got_cert);
@@ -1059,6 +1081,10 @@ int SSLClientSocketOpenSSL::DoVerifyCertComplete(int result) {
   }
 
   if (result == OK) {
+    // Only check Certificate Transparency if there were no other errors with
+    // the connection.
+    VerifyCT();
+
     // TODO(joth): Work out if we need to remember the intermediate CA certs
     // when the server sends them to us, and do so here.
     SSLContext::GetInstance()->session_cache()->MarkSSLSessionAsGood(ssl_);
@@ -1096,6 +1122,37 @@ X509Certificate* SSLClientSocketOpenSSL::UpdateServerCert() {
   return server_cert_.get();
 }
 
+void SSLClientSocketOpenSSL::VerifyCT() {
+  if (!cert_transparency_verifier_)
+    return;
+
+  uint8_t* ocsp_response;
+  size_t ocsp_response_len;
+  SSL_get0_ocsp_response(ssl_, &ocsp_response, &ocsp_response_len);
+
+  uint8_t* sct_list;
+  size_t sct_list_len;
+  SSL_get0_signed_cert_timestamp_list(ssl_, &sct_list, &sct_list_len);
+
+  // Note that this is a completely synchronous operation: The CT Log Verifier
+  // gets all the data it needs for SCT verification and does not do any
+  // external communication.
+  int result = cert_transparency_verifier_->Verify(
+      server_cert_verify_result_.verified_cert.get(),
+      std::string(reinterpret_cast<const char*>(ocsp_response),
+                  ocsp_response_len),
+      std::string(reinterpret_cast<const char*>(sct_list),
+                  sct_list_len),

[Ryan Sleevi, 2014/09/02 19:49:06]

BUG: The constructor for std::string requires that |s| (aka ocsp_response /
sct_list) be non-NULL (c.f. C++03 21.3.1 p6)

basic_string(const charT* s, size_type n,
const Allocator& a = Allocator());
6 Requires: s shall not be a null pointer and n < npos.


However, both the SSL_get0 functions return NULL in the absence of the relevant
data.

I'd suggest you restructure with

uint8_t* ocsp_response_raw;
size_t ocsp_response_len;
SSL_get0_ocsp_response(..., &.._raw, &..._len);
std::string ocsp_response;
if (...len)
   ocsp_response.assign(..._raw, ..._len);


(note that .assign and .append both inherit the non-NULL requirement)

[davidben, 2014/09/02 22:13:45]

Done.

+      &ct_verify_result_,
+      net_log_);
+
+  VLOG(1) << "CT Verification complete: result " << result
+          << " Invalid scts: " << ct_verify_result_.invalid_scts.size()
+          << " Verified scts: " << ct_verify_result_.verified_scts.size()
+          << " scts from unknown logs: "
+          << ct_verify_result_.unknown_logs_scts.size();
+}
+
 void SSLClientSocketOpenSSL::OnHandshakeIOComplete(int result) {
   int rv = DoHandshakeLoop(result);
   if (rv != ERR_IO_PENDING) {
@@ -1657,6 +1714,28 @@ void SSLClientSocketOpenSSL::CheckIfHandshakeFinished() {
     OnHandshakeCompletion();
 }
 
+void SSLClientSocketOpenSSL::AddSCTInfoToSSLInfo(SSLInfo* ssl_info) const {
+  for (ct::SCTList::const_iterator iter =
+       ct_verify_result_.verified_scts.begin();
+       iter != ct_verify_result_.verified_scts.end(); ++iter) {
+    ssl_info->signed_certificate_timestamps.push_back(
+        SignedCertificateTimestampAndStatus(*iter, ct::SCT_STATUS_OK));
+  }
+  for (ct::SCTList::const_iterator iter =
+       ct_verify_result_.invalid_scts.begin();
+       iter != ct_verify_result_.invalid_scts.end(); ++iter) {
+    ssl_info->signed_certificate_timestamps.push_back(
+        SignedCertificateTimestampAndStatus(*iter, ct::SCT_STATUS_INVALID));
+  }
+  for (ct::SCTList::const_iterator iter =
+       ct_verify_result_.unknown_logs_scts.begin();
+       iter != ct_verify_result_.unknown_logs_scts.end(); ++iter) {
+    ssl_info->signed_certificate_timestamps.push_back(
+        SignedCertificateTimestampAndStatus(*iter,
+                                            ct::SCT_STATUS_LOG_UNKNOWN));
+  }
+}
+
 scoped_refptr<X509Certificate>
 SSLClientSocketOpenSSL::GetUnverifiedServerCertificateChain() const {
   return server_cert_;