From 79511e8a50facd509b8180d0160762b510dd6196 Mon Sep 17 00:00:00 2001 From: Rahat Mahmood Date: Thu, 1 Aug 2019 13:57:41 -0700 Subject: Implement getsockopt(TCP_INFO). Export some readily-available fields for TCP_INFO and stub out the rest. PiperOrigin-RevId: 261191548 --- pkg/sentry/socket/epsocket/epsocket.go | 131 ++++++++++++++++++++++++--------- 1 file changed, 98 insertions(+), 33 deletions(-) (limited to 'pkg/sentry') diff --git a/pkg/sentry/socket/epsocket/epsocket.go b/pkg/sentry/socket/epsocket/epsocket.go index 0f483faa8..586523d3d 100644 --- a/pkg/sentry/socket/epsocket/epsocket.go +++ b/pkg/sentry/socket/epsocket/epsocket.go @@ -845,6 +845,68 @@ func getSockOptSocket(t *kernel.Task, s socket.Socket, ep commonEndpoint, family return nil, syserr.ErrProtocolNotAvailable } +func toLinuxTCPInfo(i tcp.InfoOption) linux.TCPInfo { + // Unimplemented fields are explicitly initialized to zero below. + return linux.TCPInfo{ + State: uint8(translateTCPState(tcp.EndpointState(i.ProtocolState))), + CaState: 0, + Retransmits: 0, + Probes: 0, + Backoff: 0, + Options: 0, + WindowScale: uint8((i.Sender.SndWndScale&0xf)<<4 | (i.Receiver.RcvWndScale & 0xf)), + DeliveryRateAppLimited: 0, + + RTO: uint32(i.Sender.RTO / time.Microsecond), + ATO: 0, + SndMss: uint32(i.Sender.MSS), + RcvMss: uint32(i.RcvMSS), + + Unacked: uint32(i.Sender.Outstanding), + Sacked: uint32(i.SACK.Sacked), + Lost: 0, + Retrans: 0, + Fackets: 0, + + LastDataSent: uint32(i.Sender.LastSendTime.UnixNano() / int64(time.Millisecond)), + LastAckSent: 0, // Not tracked by Linux. + LastDataRecv: uint32(i.RcvLastDataNanos / int64(time.Millisecond)), + LastAckRecv: uint32(i.RcvLastAckNanos / int64(time.Millisecond)), + + PMTU: uint32(i.SndMTU), + RcvSsthresh: 0, + RTT: uint32(i.Sender.SRTT / time.Microsecond), + RTTVar: uint32(i.Sender.RTTVar / time.Microsecond), + SndSsthresh: uint32(i.Sender.Ssthresh), + SndCwnd: uint32(i.Sender.SndCwnd), + Advmss: uint32(i.AMSS), + Reordering: 0, + + RcvRTT: uint32(i.RcvAutoParams.RTT / time.Microsecond), + RcvSpace: uint32(i.RcvBufSize), + + TotalRetrans: 0, + + PacingRate: 0, + MaxPacingRate: 0, + BytesAcked: 0, + BytesReceived: 0, + SegsOut: 0, + SegsIn: 0, + + NotSentBytes: 0, + MinRTT: uint32(i.RcvAutoParams.RTT / time.Microsecond), + DataSegsIn: 0, + DataSegsOut: 0, + + DeliveryRate: 0, + + BusyTime: 0, + RwndLimited: 0, + SndBufLimited: 0, + } +} + // getSockOptTCP implements GetSockOpt when level is SOL_TCP. func getSockOptTCP(t *kernel.Task, ep commonEndpoint, name, outLen int) (interface{}, *syserr.Error) { switch name { @@ -924,17 +986,14 @@ func getSockOptTCP(t *kernel.Task, ep commonEndpoint, name, outLen int) (interfa return int32(time.Duration(v) / time.Second), nil case linux.TCP_INFO: - var v tcpip.TCPInfoOption + var v tcp.InfoOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } - - // TODO(b/64800844): Translate fields once they are added to - // tcpip.TCPInfoOption. - info := linux.TCPInfo{} + info := toLinuxTCPInfo(v) // Linux truncates the output binary to outLen. - ib := binary.Marshal(nil, usermem.ByteOrder, &info) + ib := binary.Marshal(nil, usermem.ByteOrder, info) if len(ib) > outLen { ib = ib[:outLen] } @@ -2375,6 +2434,38 @@ func nicStateFlagsToLinux(f stack.NICStateFlags) uint32 { return rv } +// translateTCPState translates an internal endpoint state to the equivalent +// state in the Linux ABI. +func translateTCPState(s tcp.EndpointState) uint32 { + switch s { + case tcp.StateEstablished: + return linux.TCP_ESTABLISHED + case tcp.StateSynSent: + return linux.TCP_SYN_SENT + case tcp.StateSynRecv: + return linux.TCP_SYN_RECV + case tcp.StateFinWait1: + return linux.TCP_FIN_WAIT1 + case tcp.StateFinWait2: + return linux.TCP_FIN_WAIT2 + case tcp.StateTimeWait: + return linux.TCP_TIME_WAIT + case tcp.StateClose, tcp.StateInitial, tcp.StateBound, tcp.StateConnecting, tcp.StateError: + return linux.TCP_CLOSE + case tcp.StateCloseWait: + return linux.TCP_CLOSE_WAIT + case tcp.StateLastAck: + return linux.TCP_LAST_ACK + case tcp.StateListen: + return linux.TCP_LISTEN + case tcp.StateClosing: + return linux.TCP_CLOSING + default: + // Internal or unknown state. + return 0 + } +} + // State implements socket.Socket.State. State translates the internal state // returned by netstack to values defined by Linux. func (s *SocketOperations) State() uint32 { @@ -2385,33 +2476,7 @@ func (s *SocketOperations) State() uint32 { if !s.isPacketBased() { // TCP socket. - switch tcp.EndpointState(s.Endpoint.State()) { - case tcp.StateEstablished: - return linux.TCP_ESTABLISHED - case tcp.StateSynSent: - return linux.TCP_SYN_SENT - case tcp.StateSynRecv: - return linux.TCP_SYN_RECV - case tcp.StateFinWait1: - return linux.TCP_FIN_WAIT1 - case tcp.StateFinWait2: - return linux.TCP_FIN_WAIT2 - case tcp.StateTimeWait: - return linux.TCP_TIME_WAIT - case tcp.StateClose, tcp.StateInitial, tcp.StateBound, tcp.StateConnecting, tcp.StateError: - return linux.TCP_CLOSE - case tcp.StateCloseWait: - return linux.TCP_CLOSE_WAIT - case tcp.StateLastAck: - return linux.TCP_LAST_ACK - case tcp.StateListen: - return linux.TCP_LISTEN - case tcp.StateClosing: - return linux.TCP_CLOSING - default: - // Internal or unknown state. - return 0 - } + return translateTCPState(tcp.EndpointState(s.Endpoint.State())) } // TODO(b/112063468): Export states for UDP, ICMP, and raw sockets. -- cgit v1.2.3