spdycat, shrpx: TLS SNI enhancements

shrpx:
* Added an option to set the TLS SNI extension between shrpx and the
  origin on the command line

spdycat:
* If the user set an explicit host header ( using --headers ) use that
  name for the TLS SNI extension.
* Added the handshake completion time to the verbose output
* The gettimeofday call in get_time was using the incorrect structure
  ( I believe )
* In update_html_parser it was submitting the request regardless of
  the return value of add_request.

Patch from Stephen Ludin

src/shrpx.cc

@@ -520,7 +520,10 @@ void print_help(std::ostream& out)
       << "                       key file. Shrpx will choose certificates\n"
       << "                       based on the hostname indicated by client\n"
       << "                       using TLS SNI extension. This option can be\n"
-      << "                       used multiple times.\n"
+      << "    --backend-tls-sni-field=<HOST>\n"
+      << "                       Explicitly set the content of the TLS SNI\n"
+      << "                       extension.  This will default to the backend\n"
+      << "                       HOST name.\n"
       << "\n"
       << "  SPDY:\n"
       << "    -c, --spdy-max-concurrent-streams=<NUM>\n"
@@ -659,6 +662,7 @@ int main(int argc, char **argv)
       {"backend-spdy-proto", required_argument, &flag, 28},
       {"frontend-spdy-no-tls", no_argument, &flag, 29},
       {"frontend-spdy-proto", required_argument, &flag, 30},
+      {"backend-tls-sni-field", required_argument, &flag, 31},
       {0, 0, 0, 0 }
     };
     int option_index = 0;
@@ -838,6 +842,12 @@ int main(int argc, char **argv)
         cmdcfgs.push_back(std::make_pair(SHRPX_OPT_FRONTEND_SPDY_PROTO,
                                          optarg));
         break;
+      case 31:
+        // --backend-tls-sni-field
+        cmdcfgs.push_back(std::make_pair(SHRPX_OPT_BACKEND_TLS_SNI_FIELD,
+                                         optarg));
+        break;
+
       default:
         break;
       }

src/shrpx_config.cc

@@ -79,6 +79,7 @@ const char SHRPX_OPT_FRONTEND_SPDY_NO_TLS[] = "frontend-spdy-no-tls";
 const char SHRPX_OPT_FRONTEND_SPDY_PROTO[] = "frontend-spdy-proto";
 const char SHRPX_OPT_BACKEND_SPDY_NO_TLS[] = "backend-spdy-no-tls";
 const char SHRPX_OPT_BACKEND_SPDY_PROTO[] = "backend-spdy-proto";
+const char SHRPX_OPT_BACKEND_TLS_SNI_FIELD[] = "backend-tls-sni-field";
 const char SHRPX_OPT_PID_FILE[] = "pid-file";
 const char SHRPX_OPT_USER[] = "user";
 const char SHRPX_OPT_SYSLOG[] = "syslog";
@@ -300,6 +301,8 @@ int parse_config(const char *opt, const char *optarg)
     } else {
       mod_config()->spdy_downstream_version = version;
     }
+  } else if(util::strieq(opt, SHRPX_OPT_BACKEND_TLS_SNI_FIELD)) {
+    set_config_str(&mod_config()->backend_tls_sni_name, optarg);
   } else if(util::strieq(opt, SHRPX_OPT_PID_FILE)) {
     set_config_str(&mod_config()->pid_file, optarg);
   } else if(util::strieq(opt, SHRPX_OPT_USER)) {

src/shrpx_config.h

@@ -84,6 +84,7 @@ extern const char SHRPX_OPT_CACERT[];
 extern const char SHRPX_OPT_BACKEND_IPV4[];
 extern const char SHRPX_OPT_BACKEND_IPV6[];
 extern const char SHRPX_OPT_BACKEND_HTTP_PROXY_URI[];
+extern const char SHRPX_OPT_BACKEND_TLS_SNI_FIELD[];
 
 union sockaddr_union {
   sockaddr sa;
@@ -134,6 +135,7 @@ struct Config {
   uint16_t spdy_upstream_version;
   bool spdy_downstream_no_tls;
   uint16_t spdy_downstream_version;
+  char *backend_tls_sni_name;
   char *pid_file;
   uid_t uid;
   gid_t gid;

src/shrpx_spdy_session.cc

@@ -402,11 +402,19 @@ int SpdySession::initiate_connection()
         return -1;
       }
 
-      if(!ssl::numeric_host(get_config()->downstream_host)) {
+      const char *sni_name = 0;
+      if ( get_config()->backend_tls_sni_name ) {
+        sni_name = get_config()->backend_tls_sni_name;
+      }
+      else {
+        sni_name = get_config()->downstream_host;
+      }
+
+      if(!ssl::numeric_host(sni_name)) {
         // TLS extensions: SNI. There is no documentation about the return
         // code for this function (actually this is macro wrapping SSL_ctrl
         // at the time of this writing).
-        SSL_set_tlsext_host_name(ssl_, get_config()->downstream_host);
+        SSL_set_tlsext_host_name(ssl_, sni_name);
       }
       // If state_ == PROXY_CONNECTED, we has connected to the proxy
       // using fd_ and tunnel has been established.

src/spdycat.cc

@@ -396,11 +396,12 @@ void update_html_parser(SpdySession *spdySession, Request *req,
        fieldeq(uri.c_str(), u, req->uri.c_str(), req->u, UF_HOST) &&
        porteq(uri.c_str(), u, req->uri.c_str(), req->u)) {
       // No POST data for assets
-      spdySession->add_request(uri, u, 0, 0, req->level+1);
+      if ( spdySession->add_request(uri, u, 0, 0, req->level+1) ) {
         submit_request(*spdySession->sc, spdySession->hostport, config.headers,
                        spdySession->reqvec.back());
       }
     }
+  }
   req->html_parser->clear_links();
 }
 
@@ -721,7 +722,20 @@ int communicate(const std::string& host, uint16_t port,
       result = -1;
       goto fin;
     }
-    if (!SSL_set_tlsext_host_name(ssl, host.c_str())) {
+
+    // If the user overrode the host header, use that value for the
+    // SNI extension
+    const char *host_string = 0;
+    std::map<std::string,std::string>::const_iterator i =
+      config.headers.find( "Host" );
+    if ( i != config.headers.end() ) {
+      host_string = (*i).second.c_str();
+    }
+    else {
+      host_string = host.c_str();
+    }
+
+    if (!SSL_set_tlsext_host_name(ssl, host_string)) {
       std::cerr << ERR_error_string(ERR_get_error(), 0) << std::endl;
       result = -1;
       goto fin;
@@ -739,6 +753,11 @@ int communicate(const std::string& host, uint16_t port,
     }
   }
 
+  if ( config.verbose ) {
+    print_timer();
+    std::cout << " Handshake complete" << std::endl;
+  }
+
   spdySession.record_handshake_time();
   spdy_version = spdylay_npn_get_version(
       reinterpret_cast<const unsigned char*>(next_proto.c_str()),

src/spdylay_ssl.cc

@@ -916,7 +916,7 @@ int get_time(timeval *tv)
   tv->tv_sec = ts.tv_sec;
   tv->tv_usec = ts.tv_nsec/1000;
 #else // !HAVE_CLOCK_GETTIME
-  rv = gettimeofday(&base_tv, 0);
+  rv = gettimeofday(tv, 0);
 #endif // !HAVE_CLOCK_GETTIME
   return rv;
 }