Line data    Source code

       1             : #if defined(__linux__)
       2             : 
       3             : // `struct tcp_info` is defined in two places: /usr/include/netinet/tcp.h (included from
       4             : // envoy/common/platform.h) and /usr/include/linux/tcp.h. The former version is older and doesn't
       5             : // contain all the fields needed. Including both headers results in a compilation error due to the
       6             : // duplicate (and different) definitions of `struct tcp_info`. To work around this, define
       7             : // `DO_NOT_INCLUDE_NETINET_TCP_H` to prevent inclusion of the wrong version.
       8             : #define DO_NOT_INCLUDE_NETINET_TCP_H 1
       9             : 
      10             : #include "source/extensions/transport_sockets/tcp_stats/tcp_stats.h"
      11             : 
      12             : #include <linux/tcp.h>
      13             : 
      14             : #include "envoy/buffer/buffer.h"
      15             : #include "envoy/network/connection.h"
      16             : 
      17             : #include "source/common/common/assert.h"
      18             : #include "source/common/protobuf/utility.h"
      19             : 
      20             : namespace Envoy {
      21             : namespace Extensions {
      22             : namespace TransportSockets {
      23             : namespace TcpStats {
      24             : 
      25             : Config::Config(const envoy::extensions::transport_sockets::tcp_stats::v3::Config& config_proto,
      26             :                Stats::Scope& scope)
      27             :     : stats_(generateStats(scope)),
      28           0 :       update_period_(PROTOBUF_GET_OPTIONAL_MS(config_proto, update_period)) {}
      29             : 
      30           0 : TcpStats Config::generateStats(Stats::Scope& scope) {
      31           0 :   const std::string prefix("tcp_stats");
      32           0 :   return TcpStats{ALL_TCP_STATS(POOL_COUNTER_PREFIX(scope, prefix),
      33           0 :                                 POOL_GAUGE_PREFIX(scope, prefix),
      34           0 :                                 POOL_HISTOGRAM_PREFIX(scope, prefix))};
      35           0 : }
      36             : 
      37             : TcpStatsSocket::TcpStatsSocket(ConfigConstSharedPtr config,
      38             :                                Network::TransportSocketPtr inner_socket)
      39           0 :     : PassthroughSocket(std::move(inner_socket)), config_(std::move(config)) {}
      40             : 
      41           0 : void TcpStatsSocket::setTransportSocketCallbacks(Network::TransportSocketCallbacks& callbacks) {
      42           0 :   callbacks_ = &callbacks;
      43           0 :   transport_socket_->setTransportSocketCallbacks(callbacks);
      44           0 : }
      45             : 
      46           0 : void TcpStatsSocket::onConnected() {
      47           0 :   if (config_->update_period_.has_value()) {
      48           0 :     timer_ = callbacks_->connection().dispatcher().createTimer([this]() {
      49           0 :       recordStats();
      50           0 :       timer_->enableTimer(config_->update_period_.value());
      51           0 :     });
      52           0 :     timer_->enableTimer(config_->update_period_.value());
      53           0 :   }
      54             : 
      55           0 :   transport_socket_->onConnected();
      56           0 : }
      57             : 
      58           0 : void TcpStatsSocket::closeSocket(Network::ConnectionEvent event) {
      59             :   // Record final values.
      60           0 :   recordStats();
      61             : 
      62             :   // Ensure gauges are zero'd out at the end of a connection no matter what the OS told us.
      63           0 :   if (last_cx_tx_unsent_bytes_ > 0) {
      64           0 :     config_->stats_.cx_tx_unsent_bytes_.sub(last_cx_tx_unsent_bytes_);
      65           0 :   }
      66           0 :   if (last_cx_tx_unacked_segments_ > 0) {
      67           0 :     config_->stats_.cx_tx_unacked_segments_.sub(last_cx_tx_unacked_segments_);
      68           0 :   }
      69             : 
      70           0 :   if (timer_ != nullptr) {
      71           0 :     timer_->disableTimer();
      72           0 :   }
      73             : 
      74           0 :   transport_socket_->closeSocket(event);
      75           0 : }
      76             : 
      77           0 : absl::optional<struct tcp_info> TcpStatsSocket::querySocketInfo() {
      78           0 :   struct tcp_info info;
      79           0 :   memset(&info, 0, sizeof(info));
      80           0 :   socklen_t optlen = sizeof(info);
      81           0 :   const auto result = callbacks_->ioHandle().getOption(IPPROTO_TCP, TCP_INFO, &info, &optlen);
      82           0 :   if (result.return_value_ != 0) {
      83           0 :     ENVOY_LOG(debug, "Failed getsockopt(IPPROTO_TCP, TCP_INFO): rc {} errno {} optlen {}",
      84           0 :               result.return_value_, result.errno_, optlen);
      85           0 :     return absl::nullopt;
      86           0 :   } else {
      87           0 :     return info;
      88           0 :   }
      89           0 : }
      90             : 
      91           0 : void TcpStatsSocket::recordStats() {
      92           0 :   absl::optional<struct tcp_info> tcp_info = querySocketInfo();
      93           0 :   if (!tcp_info.has_value()) {
      94           0 :     return;
      95           0 :   }
      96             : 
      97           0 :   auto update_counter = [](Stats::Counter& counter, auto& last_value, auto current_value) {
      98           0 :     int64_t diff = static_cast<int64_t>(current_value) - static_cast<int64_t>(last_value);
      99           0 :     ASSERT(diff >= 0);
     100           0 :     if (diff > 0) {
     101           0 :       counter.add(diff);
     102           0 :     }
     103           0 :     last_value = current_value;
     104           0 :   };
     105             : 
     106           0 :   auto update_gauge = [](Stats::Gauge& gauge, auto& last_value, auto current_value) {
     107           0 :     static_assert(sizeof(last_value) == sizeof(current_value));
     108           0 :     int64_t diff = static_cast<int64_t>(current_value) - static_cast<int64_t>(last_value);
     109           0 :     gauge.add(diff);
     110           0 :     last_value = current_value;
     111           0 :   };
     112             : 
     113             :   // This is before the update to `cx_tx_data_segments_` and `cx_tx_retransmitted_segments_` because
     114             :   // they use the same metrics, and `update_counter` will update `last_...`, so this needs to use
     115             :   // those `last_...` values (and not update them) first.
     116             :   //
     117             :   // Don't record a value if the numerator is negative, or the denominator is zero or negative
     118             :   // (prevent divide-by-zero).
     119           0 :   if ((tcp_info->tcpi_data_segs_out > last_cx_tx_data_segments_) &&
     120           0 :       (tcp_info->tcpi_total_retrans >= last_cx_tx_retransmitted_segments_)) {
     121             :     // uint32 * uint32 cannot overflow a uint64, so this can safely be done as integer math
     122             :     // instead of floating point.
     123           0 :     static_assert((sizeof(tcp_info->tcpi_total_retrans) == sizeof(uint32_t)) &&
     124           0 :                   (Stats::Histogram::PercentScale < UINT32_MAX));
     125             : 
     126           0 :     const uint32_t data_segs_out_diff = tcp_info->tcpi_data_segs_out - last_cx_tx_data_segments_;
     127           0 :     const uint32_t retransmitted_segs_diff =
     128           0 :         tcp_info->tcpi_total_retrans - last_cx_tx_retransmitted_segments_;
     129           0 :     const uint64_t percent_retransmissions =
     130           0 :         (static_cast<uint64_t>(retransmitted_segs_diff) *
     131           0 :          static_cast<uint64_t>(Stats::Histogram::PercentScale)) /
     132           0 :         static_cast<uint64_t>(data_segs_out_diff);
     133           0 :     config_->stats_.cx_tx_percent_retransmitted_segments_.recordValue(percent_retransmissions);
     134           0 :   }
     135             : 
     136           0 :   update_counter(config_->stats_.cx_tx_segments_, last_cx_tx_segments_, tcp_info->tcpi_segs_out);
     137           0 :   update_counter(config_->stats_.cx_rx_segments_, last_cx_rx_segments_, tcp_info->tcpi_segs_in);
     138           0 :   update_counter(config_->stats_.cx_tx_data_segments_, last_cx_tx_data_segments_,
     139           0 :                  tcp_info->tcpi_data_segs_out);
     140           0 :   update_counter(config_->stats_.cx_rx_data_segments_, last_cx_rx_data_segments_,
     141           0 :                  tcp_info->tcpi_data_segs_in);
     142           0 :   update_counter(config_->stats_.cx_tx_retransmitted_segments_, last_cx_tx_retransmitted_segments_,
     143           0 :                  tcp_info->tcpi_total_retrans);
     144           0 :   update_counter(config_->stats_.cx_rx_bytes_received_, last_cx_rx_bytes_received_,
     145           0 :                  tcp_info->tcpi_bytes_received);
     146           0 :   update_counter(config_->stats_.cx_tx_bytes_sent_, last_cx_tx_bytes_sent_,
     147           0 :                  tcp_info->tcpi_bytes_sent);
     148             : 
     149           0 :   update_gauge(config_->stats_.cx_tx_unsent_bytes_, last_cx_tx_unsent_bytes_,
     150           0 :                tcp_info->tcpi_notsent_bytes);
     151           0 :   update_gauge(config_->stats_.cx_tx_unacked_segments_, last_cx_tx_unacked_segments_,
     152           0 :                tcp_info->tcpi_unacked);
     153             : 
     154           0 :   config_->stats_.cx_rtt_us_.recordValue(tcp_info->tcpi_rtt);
     155           0 :   config_->stats_.cx_rtt_variance_us_.recordValue(tcp_info->tcpi_rttvar);
     156           0 : }
     157             : 
     158             : } // namespace TcpStats
     159             : } // namespace TransportSockets
     160             : } // namespace Extensions
     161             : } // namespace Envoy
     162             : #endif // defined(__linux__)