// Copyright 2018 The gVisor Authors. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. // Package netstack provides an implementation of the socket.Socket interface // that is backed by a tcpip.Endpoint. // // It does not depend on any particular endpoint implementation, and thus can // be used to expose certain endpoints to the sentry while leaving others out, // for example, TCP endpoints and Unix-domain endpoints. // // Lock ordering: netstack => mm: ioSequencePayload copies user memory inside // tcpip.Endpoint.Write(). Netstack is allowed to (and does) hold locks during // this operation. package netstack import ( "bytes" "fmt" "io" "math" "reflect" "sync/atomic" "syscall" "time" "golang.org/x/sys/unix" "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/amutex" "gvisor.dev/gvisor/pkg/binary" "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/marshal" "gvisor.dev/gvisor/pkg/marshal/primitive" "gvisor.dev/gvisor/pkg/metric" "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" "gvisor.dev/gvisor/pkg/sentry/inet" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/netfilter" "gvisor.dev/gvisor/pkg/sentry/unimpl" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/stack" "gvisor.dev/gvisor/pkg/tcpip/transport/tcp" "gvisor.dev/gvisor/pkg/tcpip/transport/udp" "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) func mustCreateMetric(name, description string) *tcpip.StatCounter { var cm tcpip.StatCounter metric.MustRegisterCustomUint64Metric(name, true /* cumulative */, false /* sync */, description, cm.Value) return &cm } func mustCreateGauge(name, description string) *tcpip.StatCounter { var cm tcpip.StatCounter metric.MustRegisterCustomUint64Metric(name, false /* cumulative */, false /* sync */, description, cm.Value) return &cm } // Metrics contains metrics exported by netstack. var Metrics = tcpip.Stats{ UnknownProtocolRcvdPackets: mustCreateMetric("/netstack/unknown_protocol_received_packets", "Number of packets received by netstack that were for an unknown or unsupported protocol."), MalformedRcvdPackets: mustCreateMetric("/netstack/malformed_received_packets", "Number of packets received by netstack that were deemed malformed."), DroppedPackets: mustCreateMetric("/netstack/dropped_packets", "Number of packets dropped by netstack due to full queues."), ICMP: tcpip.ICMPStats{ V4PacketsSent: tcpip.ICMPv4SentPacketStats{ ICMPv4PacketStats: tcpip.ICMPv4PacketStats{ Echo: mustCreateMetric("/netstack/icmp/v4/packets_sent/echo", "Total number of ICMPv4 echo packets sent by netstack."), EchoReply: mustCreateMetric("/netstack/icmp/v4/packets_sent/echo_reply", "Total number of ICMPv4 echo reply packets sent by netstack."), DstUnreachable: mustCreateMetric("/netstack/icmp/v4/packets_sent/dst_unreachable", "Total number of ICMPv4 destination unreachable packets sent by netstack."), SrcQuench: mustCreateMetric("/netstack/icmp/v4/packets_sent/src_quench", "Total number of ICMPv4 source quench packets sent by netstack."), Redirect: mustCreateMetric("/netstack/icmp/v4/packets_sent/redirect", "Total number of ICMPv4 redirect packets sent by netstack."), TimeExceeded: mustCreateMetric("/netstack/icmp/v4/packets_sent/time_exceeded", "Total number of ICMPv4 time exceeded packets sent by netstack."), ParamProblem: mustCreateMetric("/netstack/icmp/v4/packets_sent/param_problem", "Total number of ICMPv4 parameter problem packets sent by netstack."), Timestamp: mustCreateMetric("/netstack/icmp/v4/packets_sent/timestamp", "Total number of ICMPv4 timestamp packets sent by netstack."), TimestampReply: mustCreateMetric("/netstack/icmp/v4/packets_sent/timestamp_reply", "Total number of ICMPv4 timestamp reply packets sent by netstack."), InfoRequest: mustCreateMetric("/netstack/icmp/v4/packets_sent/info_request", "Total number of ICMPv4 information request packets sent by netstack."), InfoReply: mustCreateMetric("/netstack/icmp/v4/packets_sent/info_reply", "Total number of ICMPv4 information reply packets sent by netstack."), }, Dropped: mustCreateMetric("/netstack/icmp/v4/packets_sent/dropped", "Total number of ICMPv4 packets dropped by netstack due to link layer errors."), }, V4PacketsReceived: tcpip.ICMPv4ReceivedPacketStats{ ICMPv4PacketStats: tcpip.ICMPv4PacketStats{ Echo: mustCreateMetric("/netstack/icmp/v4/packets_received/echo", "Total number of ICMPv4 echo packets received by netstack."), EchoReply: mustCreateMetric("/netstack/icmp/v4/packets_received/echo_reply", "Total number of ICMPv4 echo reply packets received by netstack."), DstUnreachable: mustCreateMetric("/netstack/icmp/v4/packets_received/dst_unreachable", "Total number of ICMPv4 destination unreachable packets received by netstack."), SrcQuench: mustCreateMetric("/netstack/icmp/v4/packets_received/src_quench", "Total number of ICMPv4 source quench packets received by netstack."), Redirect: mustCreateMetric("/netstack/icmp/v4/packets_received/redirect", "Total number of ICMPv4 redirect packets received by netstack."), TimeExceeded: mustCreateMetric("/netstack/icmp/v4/packets_received/time_exceeded", "Total number of ICMPv4 time exceeded packets received by netstack."), ParamProblem: mustCreateMetric("/netstack/icmp/v4/packets_received/param_problem", "Total number of ICMPv4 parameter problem packets received by netstack."), Timestamp: mustCreateMetric("/netstack/icmp/v4/packets_received/timestamp", "Total number of ICMPv4 timestamp packets received by netstack."), TimestampReply: mustCreateMetric("/netstack/icmp/v4/packets_received/timestamp_reply", "Total number of ICMPv4 timestamp reply packets received by netstack."), InfoRequest: mustCreateMetric("/netstack/icmp/v4/packets_received/info_request", "Total number of ICMPv4 information request packets received by netstack."), InfoReply: mustCreateMetric("/netstack/icmp/v4/packets_received/info_reply", "Total number of ICMPv4 information reply packets received by netstack."), }, Invalid: mustCreateMetric("/netstack/icmp/v4/packets_received/invalid", "Total number of ICMPv4 packets received that the transport layer could not parse."), }, V6PacketsSent: tcpip.ICMPv6SentPacketStats{ ICMPv6PacketStats: tcpip.ICMPv6PacketStats{ EchoRequest: mustCreateMetric("/netstack/icmp/v6/packets_sent/echo_request", "Total number of ICMPv6 echo request packets sent by netstack."), EchoReply: mustCreateMetric("/netstack/icmp/v6/packets_sent/echo_reply", "Total number of ICMPv6 echo reply packets sent by netstack."), DstUnreachable: mustCreateMetric("/netstack/icmp/v6/packets_sent/dst_unreachable", "Total number of ICMPv6 destination unreachable packets sent by netstack."), PacketTooBig: mustCreateMetric("/netstack/icmp/v6/packets_sent/packet_too_big", "Total number of ICMPv6 packet too big packets sent by netstack."), TimeExceeded: mustCreateMetric("/netstack/icmp/v6/packets_sent/time_exceeded", "Total number of ICMPv6 time exceeded packets sent by netstack."), ParamProblem: mustCreateMetric("/netstack/icmp/v6/packets_sent/param_problem", "Total number of ICMPv6 parameter problem packets sent by netstack."), RouterSolicit: mustCreateMetric("/netstack/icmp/v6/packets_sent/router_solicit", "Total number of ICMPv6 router solicit packets sent by netstack."), RouterAdvert: mustCreateMetric("/netstack/icmp/v6/packets_sent/router_advert", "Total number of ICMPv6 router advert packets sent by netstack."), NeighborSolicit: mustCreateMetric("/netstack/icmp/v6/packets_sent/neighbor_solicit", "Total number of ICMPv6 neighbor solicit packets sent by netstack."), NeighborAdvert: mustCreateMetric("/netstack/icmp/v6/packets_sent/neighbor_advert", "Total number of ICMPv6 neighbor advert packets sent by netstack."), RedirectMsg: mustCreateMetric("/netstack/icmp/v6/packets_sent/redirect_msg", "Total number of ICMPv6 redirect message packets sent by netstack."), }, Dropped: mustCreateMetric("/netstack/icmp/v6/packets_sent/dropped", "Total number of ICMPv6 packets dropped by netstack due to link layer errors."), }, V6PacketsReceived: tcpip.ICMPv6ReceivedPacketStats{ ICMPv6PacketStats: tcpip.ICMPv6PacketStats{ EchoRequest: mustCreateMetric("/netstack/icmp/v6/packets_received/echo_request", "Total number of ICMPv6 echo request packets received by netstack."), EchoReply: mustCreateMetric("/netstack/icmp/v6/packets_received/echo_reply", "Total number of ICMPv6 echo reply packets received by netstack."), DstUnreachable: mustCreateMetric("/netstack/icmp/v6/packets_received/dst_unreachable", "Total number of ICMPv6 destination unreachable packets received by netstack."), PacketTooBig: mustCreateMetric("/netstack/icmp/v6/packets_received/packet_too_big", "Total number of ICMPv6 packet too big packets received by netstack."), TimeExceeded: mustCreateMetric("/netstack/icmp/v6/packets_received/time_exceeded", "Total number of ICMPv6 time exceeded packets received by netstack."), ParamProblem: mustCreateMetric("/netstack/icmp/v6/packets_received/param_problem", "Total number of ICMPv6 parameter problem packets received by netstack."), RouterSolicit: mustCreateMetric("/netstack/icmp/v6/packets_received/router_solicit", "Total number of ICMPv6 router solicit packets received by netstack."), RouterAdvert: mustCreateMetric("/netstack/icmp/v6/packets_received/router_advert", "Total number of ICMPv6 router advert packets received by netstack."), NeighborSolicit: mustCreateMetric("/netstack/icmp/v6/packets_received/neighbor_solicit", "Total number of ICMPv6 neighbor solicit packets received by netstack."), NeighborAdvert: mustCreateMetric("/netstack/icmp/v6/packets_received/neighbor_advert", "Total number of ICMPv6 neighbor advert packets received by netstack."), RedirectMsg: mustCreateMetric("/netstack/icmp/v6/packets_received/redirect_msg", "Total number of ICMPv6 redirect message packets received by netstack."), }, Invalid: mustCreateMetric("/netstack/icmp/v6/packets_received/invalid", "Total number of ICMPv6 packets received that the transport layer could not parse."), }, }, IP: tcpip.IPStats{ PacketsReceived: mustCreateMetric("/netstack/ip/packets_received", "Total number of IP packets received from the link layer in nic.DeliverNetworkPacket."), InvalidDestinationAddressesReceived: mustCreateMetric("/netstack/ip/invalid_addresses_received", "Total number of IP packets received with an unknown or invalid destination address."), InvalidSourceAddressesReceived: mustCreateMetric("/netstack/ip/invalid_source_addresses_received", "Total number of IP packets received with an unknown or invalid source address."), PacketsDelivered: mustCreateMetric("/netstack/ip/packets_delivered", "Total number of incoming IP packets that are successfully delivered to the transport layer via HandlePacket."), PacketsSent: mustCreateMetric("/netstack/ip/packets_sent", "Total number of IP packets sent via WritePacket."), OutgoingPacketErrors: mustCreateMetric("/netstack/ip/outgoing_packet_errors", "Total number of IP packets which failed to write to a link-layer endpoint."), MalformedPacketsReceived: mustCreateMetric("/netstack/ip/malformed_packets_received", "Total number of IP packets which failed IP header validation checks."), MalformedFragmentsReceived: mustCreateMetric("/netstack/ip/malformed_fragments_received", "Total number of IP fragments which failed IP fragment validation checks."), IPTablesPreroutingDropped: mustCreateMetric("/netstack/ip/iptables/prerouting_dropped", "Total number of IP packets dropped in the Prerouting chain."), IPTablesInputDropped: mustCreateMetric("/netstack/ip/iptables/input_dropped", "Total number of IP packets dropped in the Input chain."), IPTablesOutputDropped: mustCreateMetric("/netstack/ip/iptables/output_dropped", "Total number of IP packets dropped in the Output chain."), }, TCP: tcpip.TCPStats{ ActiveConnectionOpenings: mustCreateMetric("/netstack/tcp/active_connection_openings", "Number of connections opened successfully via Connect."), PassiveConnectionOpenings: mustCreateMetric("/netstack/tcp/passive_connection_openings", "Number of connections opened successfully via Listen."), CurrentEstablished: mustCreateGauge("/netstack/tcp/current_established", "Number of connections in ESTABLISHED state now."), CurrentConnected: mustCreateGauge("/netstack/tcp/current_open", "Number of connections that are in connected state."), EstablishedResets: mustCreateMetric("/netstack/tcp/established_resets", "Number of times TCP connections have made a direct transition to the CLOSED state from either the ESTABLISHED state or the CLOSE-WAIT state"), EstablishedClosed: mustCreateMetric("/netstack/tcp/established_closed", "Number of times established TCP connections made a transition to CLOSED state."), EstablishedTimedout: mustCreateMetric("/netstack/tcp/established_timedout", "Number of times an established connection was reset because of keep-alive time out."), ListenOverflowSynDrop: mustCreateMetric("/netstack/tcp/listen_overflow_syn_drop", "Number of times the listen queue overflowed and a SYN was dropped."), ListenOverflowAckDrop: mustCreateMetric("/netstack/tcp/listen_overflow_ack_drop", "Number of times the listen queue overflowed and the final ACK in the handshake was dropped."), ListenOverflowSynCookieSent: mustCreateMetric("/netstack/tcp/listen_overflow_syn_cookie_sent", "Number of times a SYN cookie was sent."), ListenOverflowSynCookieRcvd: mustCreateMetric("/netstack/tcp/listen_overflow_syn_cookie_rcvd", "Number of times a SYN cookie was received."), ListenOverflowInvalidSynCookieRcvd: mustCreateMetric("/netstack/tcp/listen_overflow_invalid_syn_cookie_rcvd", "Number of times an invalid SYN cookie was received."), FailedConnectionAttempts: mustCreateMetric("/netstack/tcp/failed_connection_attempts", "Number of calls to Connect or Listen (active and passive openings, respectively) that end in an error."), ValidSegmentsReceived: mustCreateMetric("/netstack/tcp/valid_segments_received", "Number of TCP segments received that the transport layer successfully parsed."), InvalidSegmentsReceived: mustCreateMetric("/netstack/tcp/invalid_segments_received", "Number of TCP segments received that the transport layer could not parse."), SegmentsSent: mustCreateMetric("/netstack/tcp/segments_sent", "Number of TCP segments sent."), SegmentSendErrors: mustCreateMetric("/netstack/tcp/segment_send_errors", "Number of TCP segments failed to be sent."), ResetsSent: mustCreateMetric("/netstack/tcp/resets_sent", "Number of TCP resets sent."), ResetsReceived: mustCreateMetric("/netstack/tcp/resets_received", "Number of TCP resets received."), Retransmits: mustCreateMetric("/netstack/tcp/retransmits", "Number of TCP segments retransmitted."), FastRecovery: mustCreateMetric("/netstack/tcp/fast_recovery", "Number of times fast recovery was used to recover from packet loss."), SACKRecovery: mustCreateMetric("/netstack/tcp/sack_recovery", "Number of times SACK recovery was used to recover from packet loss."), SlowStartRetransmits: mustCreateMetric("/netstack/tcp/slow_start_retransmits", "Number of segments retransmitted in slow start mode."), FastRetransmit: mustCreateMetric("/netstack/tcp/fast_retransmit", "Number of TCP segments which were fast retransmitted."), Timeouts: mustCreateMetric("/netstack/tcp/timeouts", "Number of times RTO expired."), ChecksumErrors: mustCreateMetric("/netstack/tcp/checksum_errors", "Number of segments dropped due to bad checksums."), }, UDP: tcpip.UDPStats{ PacketsReceived: mustCreateMetric("/netstack/udp/packets_received", "Number of UDP datagrams received via HandlePacket."), UnknownPortErrors: mustCreateMetric("/netstack/udp/unknown_port_errors", "Number of incoming UDP datagrams dropped because they did not have a known destination port."), ReceiveBufferErrors: mustCreateMetric("/netstack/udp/receive_buffer_errors", "Number of incoming UDP datagrams dropped due to the receiving buffer being in an invalid state."), MalformedPacketsReceived: mustCreateMetric("/netstack/udp/malformed_packets_received", "Number of incoming UDP datagrams dropped due to the UDP header being in a malformed state."), PacketsSent: mustCreateMetric("/netstack/udp/packets_sent", "Number of UDP datagrams sent."), PacketSendErrors: mustCreateMetric("/netstack/udp/packet_send_errors", "Number of UDP datagrams failed to be sent."), ChecksumErrors: mustCreateMetric("/netstack/udp/checksum_errors", "Number of UDP datagrams dropped due to bad checksums."), }, } // DefaultTTL is linux's default TTL. All network protocols in all stacks used // with this package must have this value set as their default TTL. const DefaultTTL = 64 const sizeOfInt32 int = 4 var errStackType = syserr.New("expected but did not receive a netstack.Stack", linux.EINVAL) // ntohs converts a 16-bit number from network byte order to host byte order. It // assumes that the host is little endian. func ntohs(v uint16) uint16 { return v<<8 | v>>8 } // htons converts a 16-bit number from host byte order to network byte order. It // assumes that the host is little endian. func htons(v uint16) uint16 { return ntohs(v) } // commonEndpoint represents the intersection of a tcpip.Endpoint and a // transport.Endpoint. type commonEndpoint interface { // GetLocalAddress implements tcpip.Endpoint.GetLocalAddress and // transport.Endpoint.GetLocalAddress. GetLocalAddress() (tcpip.FullAddress, *tcpip.Error) // GetRemoteAddress implements tcpip.Endpoint.GetRemoteAddress and // transport.Endpoint.GetRemoteAddress. GetRemoteAddress() (tcpip.FullAddress, *tcpip.Error) // Readiness implements tcpip.Endpoint.Readiness and // transport.Endpoint.Readiness. Readiness(mask waiter.EventMask) waiter.EventMask // SetSockOpt implements tcpip.Endpoint.SetSockOpt and // transport.Endpoint.SetSockOpt. SetSockOpt(tcpip.SettableSocketOption) *tcpip.Error // SetSockOptBool implements tcpip.Endpoint.SetSockOptBool and // transport.Endpoint.SetSockOptBool. SetSockOptBool(opt tcpip.SockOptBool, v bool) *tcpip.Error // SetSockOptInt implements tcpip.Endpoint.SetSockOptInt and // transport.Endpoint.SetSockOptInt. SetSockOptInt(opt tcpip.SockOptInt, v int) *tcpip.Error // GetSockOpt implements tcpip.Endpoint.GetSockOpt and // transport.Endpoint.GetSockOpt. GetSockOpt(tcpip.GettableSocketOption) *tcpip.Error // GetSockOptBool implements tcpip.Endpoint.GetSockOptBool and // transport.Endpoint.GetSockOpt. GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) // GetSockOptInt implements tcpip.Endpoint.GetSockOptInt and // transport.Endpoint.GetSockOpt. GetSockOptInt(opt tcpip.SockOptInt) (int, *tcpip.Error) // LastError implements tcpip.Endpoint.LastError. LastError() *tcpip.Error // SocketOptions implements tcpip.Endpoint.SocketOptions. SocketOptions() *tcpip.SocketOptions } // LINT.IfChange // SocketOperations encapsulates all the state needed to represent a network stack // endpoint in the kernel context. // // +stateify savable type SocketOperations struct { fsutil.FilePipeSeek `state:"nosave"` fsutil.FileNotDirReaddir `state:"nosave"` fsutil.FileNoopFlush `state:"nosave"` fsutil.FileNoFsync `state:"nosave"` fsutil.FileNoMMap `state:"nosave"` fsutil.FileUseInodeUnstableAttr `state:"nosave"` socketOpsCommon } // socketOpsCommon contains the socket operations common to VFS1 and VFS2. // // +stateify savable type socketOpsCommon struct { socket.SendReceiveTimeout *waiter.Queue family int Endpoint tcpip.Endpoint skType linux.SockType protocol int // readViewHasData is 1 iff readView has data to be read, 0 otherwise. // Must be accessed using atomic operations. It must only be written // with readMu held but can be read without holding readMu. The latter // is required to avoid deadlocks in epoll Readiness checks. readViewHasData uint32 // readMu protects access to the below fields. readMu sync.Mutex `state:"nosave"` // readView contains the remaining payload from the last packet. readView buffer.View // readCM holds control message information for the last packet read // from Endpoint. readCM tcpip.ControlMessages sender tcpip.FullAddress linkPacketInfo tcpip.LinkPacketInfo // sockOptTimestamp corresponds to SO_TIMESTAMP. When true, timestamps // of returned messages can be returned via control messages. When // false, the same timestamp is instead stored and can be read via the // SIOCGSTAMP ioctl. It is protected by readMu. See socket(7). sockOptTimestamp bool // timestampValid indicates whether timestamp for SIOCGSTAMP has been // set. It is protected by readMu. timestampValid bool // timestampNS holds the timestamp to use with SIOCTSTAMP. It is only // valid when timestampValid is true. It is protected by readMu. timestampNS int64 // sockOptInq corresponds to TCP_INQ. It is implemented at this level // because it takes into account data from readView. sockOptInq bool } // New creates a new endpoint socket. func New(t *kernel.Task, family int, skType linux.SockType, protocol int, queue *waiter.Queue, endpoint tcpip.Endpoint) (*fs.File, *syserr.Error) { if skType == linux.SOCK_STREAM { if err := endpoint.SetSockOptBool(tcpip.DelayOption, true); err != nil { return nil, syserr.TranslateNetstackError(err) } } dirent := socket.NewDirent(t, netstackDevice) defer dirent.DecRef(t) return fs.NewFile(t, dirent, fs.FileFlags{Read: true, Write: true, NonSeekable: true}, &SocketOperations{ socketOpsCommon: socketOpsCommon{ Queue: queue, family: family, Endpoint: endpoint, skType: skType, protocol: protocol, }, }), nil } var sockAddrInetSize = int(binary.Size(linux.SockAddrInet{})) var sockAddrInet6Size = int(binary.Size(linux.SockAddrInet6{})) var sockAddrLinkSize = int(binary.Size(linux.SockAddrLink{})) // bytesToIPAddress converts an IPv4 or IPv6 address from the user to the // netstack representation taking any addresses into account. func bytesToIPAddress(addr []byte) tcpip.Address { if bytes.Equal(addr, make([]byte, 4)) || bytes.Equal(addr, make([]byte, 16)) { return "" } return tcpip.Address(addr) } // AddressAndFamily reads an sockaddr struct from the given address and // converts it to the FullAddress format. It supports AF_UNIX, AF_INET, // AF_INET6, and AF_PACKET addresses. // // AddressAndFamily returns an address and its family. func AddressAndFamily(addr []byte) (tcpip.FullAddress, uint16, *syserr.Error) { // Make sure we have at least 2 bytes for the address family. if len(addr) < 2 { return tcpip.FullAddress{}, 0, syserr.ErrInvalidArgument } // Get the rest of the fields based on the address family. switch family := usermem.ByteOrder.Uint16(addr); family { case linux.AF_UNIX: path := addr[2:] if len(path) > linux.UnixPathMax { return tcpip.FullAddress{}, family, syserr.ErrInvalidArgument } // Drop the terminating NUL (if one exists) and everything after // it for filesystem (non-abstract) addresses. if len(path) > 0 && path[0] != 0 { if n := bytes.IndexByte(path[1:], 0); n >= 0 { path = path[:n+1] } } return tcpip.FullAddress{ Addr: tcpip.Address(path), }, family, nil case linux.AF_INET: var a linux.SockAddrInet if len(addr) < sockAddrInetSize { return tcpip.FullAddress{}, family, syserr.ErrInvalidArgument } binary.Unmarshal(addr[:sockAddrInetSize], usermem.ByteOrder, &a) out := tcpip.FullAddress{ Addr: bytesToIPAddress(a.Addr[:]), Port: ntohs(a.Port), } return out, family, nil case linux.AF_INET6: var a linux.SockAddrInet6 if len(addr) < sockAddrInet6Size { return tcpip.FullAddress{}, family, syserr.ErrInvalidArgument } binary.Unmarshal(addr[:sockAddrInet6Size], usermem.ByteOrder, &a) out := tcpip.FullAddress{ Addr: bytesToIPAddress(a.Addr[:]), Port: ntohs(a.Port), } if isLinkLocal(out.Addr) { out.NIC = tcpip.NICID(a.Scope_id) } return out, family, nil case linux.AF_PACKET: var a linux.SockAddrLink if len(addr) < sockAddrLinkSize { return tcpip.FullAddress{}, family, syserr.ErrInvalidArgument } binary.Unmarshal(addr[:sockAddrLinkSize], usermem.ByteOrder, &a) if a.Family != linux.AF_PACKET || a.HardwareAddrLen != header.EthernetAddressSize { return tcpip.FullAddress{}, family, syserr.ErrInvalidArgument } // TODO(gvisor.dev/issue/173): Return protocol too. return tcpip.FullAddress{ NIC: tcpip.NICID(a.InterfaceIndex), Addr: tcpip.Address(a.HardwareAddr[:header.EthernetAddressSize]), }, family, nil case linux.AF_UNSPEC: return tcpip.FullAddress{}, family, nil default: return tcpip.FullAddress{}, 0, syserr.ErrAddressFamilyNotSupported } } func (s *socketOpsCommon) isPacketBased() bool { return s.skType == linux.SOCK_DGRAM || s.skType == linux.SOCK_SEQPACKET || s.skType == linux.SOCK_RDM || s.skType == linux.SOCK_RAW } // fetchReadView updates the readView field of the socket if it's currently // empty. It assumes that the socket is locked. // // Precondition: s.readMu must be held. func (s *socketOpsCommon) fetchReadView() *syserr.Error { if len(s.readView) > 0 { return nil } s.readView = nil s.sender = tcpip.FullAddress{} s.linkPacketInfo = tcpip.LinkPacketInfo{} var v buffer.View var cms tcpip.ControlMessages var err *tcpip.Error switch e := s.Endpoint.(type) { // The ordering of these interfaces matters. The most specific // interfaces must be specified before the more generic Endpoint // interface. case tcpip.PacketEndpoint: v, cms, err = e.ReadPacket(&s.sender, &s.linkPacketInfo) case tcpip.Endpoint: v, cms, err = e.Read(&s.sender) } if err != nil { atomic.StoreUint32(&s.readViewHasData, 0) return syserr.TranslateNetstackError(err) } s.readView = v s.readCM = cms atomic.StoreUint32(&s.readViewHasData, 1) return nil } // Release implements fs.FileOperations.Release. func (s *socketOpsCommon) Release(ctx context.Context) { e, ch := waiter.NewChannelEntry(nil) s.EventRegister(&e, waiter.EventHUp|waiter.EventErr) defer s.EventUnregister(&e) s.Endpoint.Close() // SO_LINGER option is valid only for TCP. For other socket types // return after endpoint close. if family, skType, _ := s.Type(); skType != linux.SOCK_STREAM || (family != linux.AF_INET && family != linux.AF_INET6) { return } var v tcpip.LingerOption if err := s.Endpoint.GetSockOpt(&v); err != nil { return } // The case for zero timeout is handled in tcp endpoint close function. // Close is blocked until either: // 1. The endpoint state is not in any of the states: FIN-WAIT1, // CLOSING and LAST_ACK. // 2. Timeout is reached. if v.Enabled && v.Timeout != 0 { t := kernel.TaskFromContext(ctx) start := t.Kernel().MonotonicClock().Now() deadline := start.Add(v.Timeout) t.BlockWithDeadline(ch, true, deadline) } } // Read implements fs.FileOperations.Read. func (s *SocketOperations) Read(ctx context.Context, _ *fs.File, dst usermem.IOSequence, _ int64) (int64, error) { if dst.NumBytes() == 0 { return 0, nil } n, _, _, _, _, err := s.nonBlockingRead(ctx, dst, false, false, false) if err == syserr.ErrWouldBlock { return int64(n), syserror.ErrWouldBlock } if err != nil { return 0, err.ToError() } return int64(n), nil } // WriteTo implements fs.FileOperations.WriteTo. func (s *SocketOperations) WriteTo(ctx context.Context, _ *fs.File, dst io.Writer, count int64, dup bool) (int64, error) { s.readMu.Lock() // Copy as much data as possible. done := int64(0) for count > 0 { // This may return a blocking error. if err := s.fetchReadView(); err != nil { s.readMu.Unlock() return done, err.ToError() } // Write to the underlying file. n, err := dst.Write(s.readView) done += int64(n) count -= int64(n) if dup { // That's all we support for dup. This is generally // supported by any Linux system calls, but the // expectation is that now a caller will call read to // actually remove these bytes from the socket. break } // Drop that part of the view. s.readView.TrimFront(n) if err != nil { s.readMu.Unlock() return done, err } } s.readMu.Unlock() return done, nil } // ioSequencePayload implements tcpip.Payload. // // t copies user memory bytes on demand based on the requested size. type ioSequencePayload struct { ctx context.Context src usermem.IOSequence } // FullPayload implements tcpip.Payloader.FullPayload func (i *ioSequencePayload) FullPayload() ([]byte, *tcpip.Error) { return i.Payload(int(i.src.NumBytes())) } // Payload implements tcpip.Payloader.Payload. func (i *ioSequencePayload) Payload(size int) ([]byte, *tcpip.Error) { if max := int(i.src.NumBytes()); size > max { size = max } v := buffer.NewView(size) if _, err := i.src.CopyIn(i.ctx, v); err != nil { // EOF can be returned only if src is a file and this means it // is in a splice syscall and the error has to be ignored. if err == io.EOF { return v, nil } return nil, tcpip.ErrBadAddress } return v, nil } // DropFirst drops the first n bytes from underlying src. func (i *ioSequencePayload) DropFirst(n int) { i.src = i.src.DropFirst(int(n)) } // Write implements fs.FileOperations.Write. func (s *SocketOperations) Write(ctx context.Context, _ *fs.File, src usermem.IOSequence, _ int64) (int64, error) { f := &ioSequencePayload{ctx: ctx, src: src} n, resCh, err := s.Endpoint.Write(f, tcpip.WriteOptions{}) if err == tcpip.ErrWouldBlock { return 0, syserror.ErrWouldBlock } if resCh != nil { if err := amutex.Block(ctx, resCh); err != nil { return 0, err } n, _, err = s.Endpoint.Write(f, tcpip.WriteOptions{}) } if err != nil { return 0, syserr.TranslateNetstackError(err).ToError() } if int64(n) < src.NumBytes() { return int64(n), syserror.ErrWouldBlock } return int64(n), nil } // readerPayload implements tcpip.Payloader. // // It allocates a view and reads from a reader on-demand, based on available // capacity in the endpoint. type readerPayload struct { ctx context.Context r io.Reader count int64 err error } // FullPayload implements tcpip.Payloader.FullPayload. func (r *readerPayload) FullPayload() ([]byte, *tcpip.Error) { return r.Payload(int(r.count)) } // Payload implements tcpip.Payloader.Payload. func (r *readerPayload) Payload(size int) ([]byte, *tcpip.Error) { if size > int(r.count) { size = int(r.count) } v := buffer.NewView(size) n, err := r.r.Read(v) if n > 0 { // We ignore the error here. It may re-occur on subsequent // reads, but for now we can enqueue some amount of data. r.count -= int64(n) return v[:n], nil } if err == syserror.ErrWouldBlock { return nil, tcpip.ErrWouldBlock } else if err != nil { r.err = err // Save for propation. return nil, tcpip.ErrBadAddress } // There is no data and no error. Return an error, which will propagate // r.err, which will be nil. This is the desired result: (0, nil). return nil, tcpip.ErrBadAddress } // ReadFrom implements fs.FileOperations.ReadFrom. func (s *SocketOperations) ReadFrom(ctx context.Context, _ *fs.File, r io.Reader, count int64) (int64, error) { f := &readerPayload{ctx: ctx, r: r, count: count} n, resCh, err := s.Endpoint.Write(f, tcpip.WriteOptions{ // Reads may be destructive but should be very fast, // so we can't release the lock while copying data. Atomic: true, }) if err == tcpip.ErrWouldBlock { return 0, syserror.ErrWouldBlock } if resCh != nil { if err := amutex.Block(ctx, resCh); err != nil { return 0, err } n, _, err = s.Endpoint.Write(f, tcpip.WriteOptions{ Atomic: true, // See above. }) } if err == tcpip.ErrWouldBlock { return n, syserror.ErrWouldBlock } else if err != nil { return int64(n), f.err // Propagate error. } return int64(n), nil } // Readiness returns a mask of ready events for socket s. func (s *socketOpsCommon) Readiness(mask waiter.EventMask) waiter.EventMask { r := s.Endpoint.Readiness(mask) // Check our cached value iff the caller asked for readability and the // endpoint itself is currently not readable. if (mask & ^r & waiter.EventIn) != 0 { if atomic.LoadUint32(&s.readViewHasData) == 1 { r |= waiter.EventIn } } return r } func (s *socketOpsCommon) checkFamily(family uint16, exact bool) *syserr.Error { if family == uint16(s.family) { return nil } if !exact && family == linux.AF_INET && s.family == linux.AF_INET6 { v, err := s.Endpoint.GetSockOptBool(tcpip.V6OnlyOption) if err != nil { return syserr.TranslateNetstackError(err) } if !v { return nil } } return syserr.ErrInvalidArgument } // mapFamily maps the AF_INET ANY address to the IPv4-mapped IPv6 ANY if the // receiver's family is AF_INET6. // // This is a hack to work around the fact that both IPv4 and IPv6 ANY are // represented by the empty string. // // TODO(gvisor.dev/issue/1556): remove this function. func (s *socketOpsCommon) mapFamily(addr tcpip.FullAddress, family uint16) tcpip.FullAddress { if len(addr.Addr) == 0 && s.family == linux.AF_INET6 && family == linux.AF_INET { addr.Addr = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\x00\x00\x00\x00" } return addr } // Connect implements the linux syscall connect(2) for sockets backed by // tpcip.Endpoint. func (s *socketOpsCommon) Connect(t *kernel.Task, sockaddr []byte, blocking bool) *syserr.Error { addr, family, err := AddressAndFamily(sockaddr) if err != nil { return err } if family == linux.AF_UNSPEC { err := s.Endpoint.Disconnect() if err == tcpip.ErrNotSupported { return syserr.ErrAddressFamilyNotSupported } return syserr.TranslateNetstackError(err) } if err := s.checkFamily(family, false /* exact */); err != nil { return err } addr = s.mapFamily(addr, family) // Always return right away in the non-blocking case. if !blocking { return syserr.TranslateNetstackError(s.Endpoint.Connect(addr)) } // Register for notification when the endpoint becomes writable, then // initiate the connection. e, ch := waiter.NewChannelEntry(nil) s.EventRegister(&e, waiter.EventOut) defer s.EventUnregister(&e) if err := s.Endpoint.Connect(addr); err != tcpip.ErrConnectStarted && err != tcpip.ErrAlreadyConnecting { if (s.family == unix.AF_INET || s.family == unix.AF_INET6) && s.skType == linux.SOCK_STREAM { // TCP unlike UDP returns EADDRNOTAVAIL when it can't // find an available local ephemeral port. if err == tcpip.ErrNoPortAvailable { return syserr.ErrAddressNotAvailable } } return syserr.TranslateNetstackError(err) } // It's pending, so we have to wait for a notification, and fetch the // result once the wait completes. if err := t.Block(ch); err != nil { return syserr.FromError(err) } // Call Connect() again after blocking to find connect's result. return syserr.TranslateNetstackError(s.Endpoint.Connect(addr)) } // Bind implements the linux syscall bind(2) for sockets backed by // tcpip.Endpoint. func (s *socketOpsCommon) Bind(t *kernel.Task, sockaddr []byte) *syserr.Error { if len(sockaddr) < 2 { return syserr.ErrInvalidArgument } family := usermem.ByteOrder.Uint16(sockaddr) var addr tcpip.FullAddress // Bind for AF_PACKET requires only family, protocol and ifindex. // In function AddressAndFamily, we check the address length which is // not needed for AF_PACKET bind. if family == linux.AF_PACKET { var a linux.SockAddrLink if len(sockaddr) < sockAddrLinkSize { return syserr.ErrInvalidArgument } binary.Unmarshal(sockaddr[:sockAddrLinkSize], usermem.ByteOrder, &a) if a.Protocol != uint16(s.protocol) { return syserr.ErrInvalidArgument } addr = tcpip.FullAddress{ NIC: tcpip.NICID(a.InterfaceIndex), Addr: tcpip.Address(a.HardwareAddr[:header.EthernetAddressSize]), } } else { var err *syserr.Error addr, family, err = AddressAndFamily(sockaddr) if err != nil { return err } if err = s.checkFamily(family, true /* exact */); err != nil { return err } addr = s.mapFamily(addr, family) } // Issue the bind request to the endpoint. err := s.Endpoint.Bind(addr) if err == tcpip.ErrNoPortAvailable { // Bind always returns EADDRINUSE irrespective of if the specified port was // already bound or if an ephemeral port was requested but none were // available. // // tcpip.ErrNoPortAvailable is mapped to EAGAIN in syserr package because // UDP connect returns EAGAIN on ephemeral port exhaustion. // // TCP connect returns EADDRNOTAVAIL on ephemeral port exhaustion. err = tcpip.ErrPortInUse } return syserr.TranslateNetstackError(err) } // Listen implements the linux syscall listen(2) for sockets backed by // tcpip.Endpoint. func (s *socketOpsCommon) Listen(t *kernel.Task, backlog int) *syserr.Error { return syserr.TranslateNetstackError(s.Endpoint.Listen(backlog)) } // blockingAccept implements a blocking version of accept(2), that is, if no // connections are ready to be accept, it will block until one becomes ready. func (s *socketOpsCommon) blockingAccept(t *kernel.Task, peerAddr *tcpip.FullAddress) (tcpip.Endpoint, *waiter.Queue, *syserr.Error) { // Register for notifications. e, ch := waiter.NewChannelEntry(nil) s.EventRegister(&e, waiter.EventIn) defer s.EventUnregister(&e) // Try to accept the connection again; if it fails, then wait until we // get a notification. for { if ep, wq, err := s.Endpoint.Accept(peerAddr); err != tcpip.ErrWouldBlock { return ep, wq, syserr.TranslateNetstackError(err) } if err := t.Block(ch); err != nil { return nil, nil, syserr.FromError(err) } } } // Accept implements the linux syscall accept(2) for sockets backed by // tcpip.Endpoint. func (s *SocketOperations) Accept(t *kernel.Task, peerRequested bool, flags int, blocking bool) (int32, linux.SockAddr, uint32, *syserr.Error) { var peerAddr *tcpip.FullAddress if peerRequested { peerAddr = &tcpip.FullAddress{} } ep, wq, terr := s.Endpoint.Accept(peerAddr) if terr != nil { if terr != tcpip.ErrWouldBlock || !blocking { return 0, nil, 0, syserr.TranslateNetstackError(terr) } var err *syserr.Error ep, wq, err = s.blockingAccept(t, peerAddr) if err != nil { return 0, nil, 0, err } } ns, err := New(t, s.family, s.skType, s.protocol, wq, ep) if err != nil { return 0, nil, 0, err } defer ns.DecRef(t) if flags&linux.SOCK_NONBLOCK != 0 { flags := ns.Flags() flags.NonBlocking = true ns.SetFlags(flags.Settable()) } var addr linux.SockAddr var addrLen uint32 if peerAddr != nil { addr, addrLen = ConvertAddress(s.family, *peerAddr) } fd, e := t.NewFDFrom(0, ns, kernel.FDFlags{ CloseOnExec: flags&linux.SOCK_CLOEXEC != 0, }) t.Kernel().RecordSocket(ns) return fd, addr, addrLen, syserr.FromError(e) } // ConvertShutdown converts Linux shutdown flags into tcpip shutdown flags. func ConvertShutdown(how int) (tcpip.ShutdownFlags, *syserr.Error) { var f tcpip.ShutdownFlags switch how { case linux.SHUT_RD: f = tcpip.ShutdownRead case linux.SHUT_WR: f = tcpip.ShutdownWrite case linux.SHUT_RDWR: f = tcpip.ShutdownRead | tcpip.ShutdownWrite default: return 0, syserr.ErrInvalidArgument } return f, nil } // Shutdown implements the linux syscall shutdown(2) for sockets backed by // tcpip.Endpoint. func (s *socketOpsCommon) Shutdown(t *kernel.Task, how int) *syserr.Error { f, err := ConvertShutdown(how) if err != nil { return err } // Issue shutdown request. return syserr.TranslateNetstackError(s.Endpoint.Shutdown(f)) } // GetSockOpt implements the linux syscall getsockopt(2) for sockets backed by // tcpip.Endpoint. func (s *SocketOperations) GetSockOpt(t *kernel.Task, level, name int, outPtr usermem.Addr, outLen int) (marshal.Marshallable, *syserr.Error) { // TODO(b/78348848): Unlike other socket options, SO_TIMESTAMP is // implemented specifically for netstack.SocketOperations rather than // commonEndpoint. commonEndpoint should be extended to support socket // options where the implementation is not shared, as unix sockets need // their own support for SO_TIMESTAMP. if level == linux.SOL_SOCKET && name == linux.SO_TIMESTAMP { if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } val := primitive.Int32(0) s.readMu.Lock() defer s.readMu.Unlock() if s.sockOptTimestamp { val = 1 } return &val, nil } if level == linux.SOL_TCP && name == linux.TCP_INQ { if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } val := primitive.Int32(0) s.readMu.Lock() defer s.readMu.Unlock() if s.sockOptInq { val = 1 } return &val, nil } return GetSockOpt(t, s, s.Endpoint, s.family, s.skType, level, name, outPtr, outLen) } // GetSockOpt can be used to implement the linux syscall getsockopt(2) for // sockets backed by a commonEndpoint. func GetSockOpt(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, family int, skType linux.SockType, level, name int, outPtr usermem.Addr, outLen int) (marshal.Marshallable, *syserr.Error) { switch level { case linux.SOL_SOCKET: return getSockOptSocket(t, s, ep, family, skType, name, outLen) case linux.SOL_TCP: return getSockOptTCP(t, ep, name, outLen) case linux.SOL_IPV6: return getSockOptIPv6(t, s, ep, name, outPtr, outLen) case linux.SOL_IP: return getSockOptIP(t, s, ep, name, outPtr, outLen, family) case linux.SOL_UDP, linux.SOL_ICMPV6, linux.SOL_RAW, linux.SOL_PACKET: t.Kernel().EmitUnimplementedEvent(t) } return nil, syserr.ErrProtocolNotAvailable } func boolToInt32(v bool) int32 { if v { return 1 } return 0 } // getSockOptSocket implements GetSockOpt when level is SOL_SOCKET. func getSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, family int, skType linux.SockType, name, outLen int) (marshal.Marshallable, *syserr.Error) { // TODO(b/124056281): Stop rejecting short optLen values in getsockopt. switch name { case linux.SO_ERROR: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } // Get the last error and convert it. err := ep.LastError() if err == nil { optP := primitive.Int32(0) return &optP, nil } optP := primitive.Int32(syserr.TranslateNetstackError(err).ToLinux().Number()) return &optP, nil case linux.SO_PEERCRED: if family != linux.AF_UNIX || outLen < syscall.SizeofUcred { return nil, syserr.ErrInvalidArgument } tcred := t.Credentials() creds := linux.ControlMessageCredentials{ PID: int32(t.ThreadGroup().ID()), UID: uint32(tcred.EffectiveKUID.In(tcred.UserNamespace).OrOverflow()), GID: uint32(tcred.EffectiveKGID.In(tcred.UserNamespace).OrOverflow()), } return &creds, nil case linux.SO_PASSCRED: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.PasscredOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.SO_SNDBUF: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } size, err := ep.GetSockOptInt(tcpip.SendBufferSizeOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } if size > math.MaxInt32 { size = math.MaxInt32 } sizeP := primitive.Int32(size) return &sizeP, nil case linux.SO_RCVBUF: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } size, err := ep.GetSockOptInt(tcpip.ReceiveBufferSizeOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } if size > math.MaxInt32 { size = math.MaxInt32 } sizeP := primitive.Int32(size) return &sizeP, nil case linux.SO_REUSEADDR: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.ReuseAddressOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.SO_REUSEPORT: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.ReusePortOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.SO_BINDTODEVICE: var v tcpip.BindToDeviceOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } if v == 0 { var b primitive.ByteSlice return &b, nil } if outLen < linux.IFNAMSIZ { return nil, syserr.ErrInvalidArgument } s := t.NetworkContext() if s == nil { return nil, syserr.ErrNoDevice } nic, ok := s.Interfaces()[int32(v)] if !ok { // The NICID no longer indicates a valid interface, probably because that // interface was removed. return nil, syserr.ErrUnknownDevice } name := primitive.ByteSlice(append([]byte(nic.Name), 0)) return &name, nil case linux.SO_BROADCAST: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v := primitive.Int32(boolToInt32(ep.SocketOptions().GetBroadcast())) return &v, nil case linux.SO_KEEPALIVE: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.KeepaliveEnabledOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.SO_LINGER: if outLen < linux.SizeOfLinger { return nil, syserr.ErrInvalidArgument } var v tcpip.LingerOption var linger linux.Linger if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } if v.Enabled { linger.OnOff = 1 } linger.Linger = int32(v.Timeout.Seconds()) return &linger, nil case linux.SO_SNDTIMEO: // TODO(igudger): Linux allows shorter lengths for partial results. if outLen < linux.SizeOfTimeval { return nil, syserr.ErrInvalidArgument } sendTimeout := linux.NsecToTimeval(s.SendTimeout()) return &sendTimeout, nil case linux.SO_RCVTIMEO: // TODO(igudger): Linux allows shorter lengths for partial results. if outLen < linux.SizeOfTimeval { return nil, syserr.ErrInvalidArgument } recvTimeout := linux.NsecToTimeval(s.RecvTimeout()) return &recvTimeout, nil case linux.SO_OOBINLINE: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } var v tcpip.OutOfBandInlineOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(v) return &vP, nil case linux.SO_NO_CHECK: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.NoChecksumOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.SO_ACCEPTCONN: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.AcceptConnOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil default: socket.GetSockOptEmitUnimplementedEvent(t, name) } return nil, syserr.ErrProtocolNotAvailable } // getSockOptTCP implements GetSockOpt when level is SOL_TCP. func getSockOptTCP(t *kernel.Task, ep commonEndpoint, name, outLen int) (marshal.Marshallable, *syserr.Error) { switch name { case linux.TCP_NODELAY: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.DelayOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(!v)) return &vP, nil case linux.TCP_CORK: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.CorkOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.TCP_QUICKACK: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.QuickAckOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.TCP_MAXSEG: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptInt(tcpip.MaxSegOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(v) return &vP, nil case linux.TCP_KEEPIDLE: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } var v tcpip.KeepaliveIdleOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } keepAliveIdle := primitive.Int32(time.Duration(v) / time.Second) return &keepAliveIdle, nil case linux.TCP_KEEPINTVL: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } var v tcpip.KeepaliveIntervalOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } keepAliveInterval := primitive.Int32(time.Duration(v) / time.Second) return &keepAliveInterval, nil case linux.TCP_KEEPCNT: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptInt(tcpip.KeepaliveCountOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(v) return &vP, nil case linux.TCP_USER_TIMEOUT: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } var v tcpip.TCPUserTimeoutOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } tcpUserTimeout := primitive.Int32(time.Duration(v) / time.Millisecond) return &tcpUserTimeout, nil case linux.TCP_INFO: var v tcpip.TCPInfoOption 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{} // Linux truncates the output binary to outLen. buf := t.CopyScratchBuffer(info.SizeBytes()) info.MarshalUnsafe(buf) if len(buf) > outLen { buf = buf[:outLen] } bufP := primitive.ByteSlice(buf) return &bufP, nil case linux.TCP_CC_INFO, linux.TCP_NOTSENT_LOWAT, linux.TCP_ZEROCOPY_RECEIVE: t.Kernel().EmitUnimplementedEvent(t) case linux.TCP_CONGESTION: if outLen <= 0 { return nil, syserr.ErrInvalidArgument } var v tcpip.CongestionControlOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } // We match linux behaviour here where it returns the lower of // TCP_CA_NAME_MAX bytes or the value of the option length. // // This is Linux's net/tcp.h TCP_CA_NAME_MAX. const tcpCANameMax = 16 toCopy := tcpCANameMax if outLen < tcpCANameMax { toCopy = outLen } b := make([]byte, toCopy) copy(b, v) bP := primitive.ByteSlice(b) return &bP, nil case linux.TCP_LINGER2: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } var v tcpip.TCPLingerTimeoutOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } var lingerTimeout primitive.Int32 if v >= 0 { lingerTimeout = primitive.Int32(time.Duration(v) / time.Second) } else { lingerTimeout = -1 } return &lingerTimeout, nil case linux.TCP_DEFER_ACCEPT: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } var v tcpip.TCPDeferAcceptOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } tcpDeferAccept := primitive.Int32(time.Duration(v) / time.Second) return &tcpDeferAccept, nil case linux.TCP_SYNCNT: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptInt(tcpip.TCPSynCountOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(v) return &vP, nil case linux.TCP_WINDOW_CLAMP: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptInt(tcpip.TCPWindowClampOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(v) return &vP, nil default: emitUnimplementedEventTCP(t, name) } return nil, syserr.ErrProtocolNotAvailable } // getSockOptIPv6 implements GetSockOpt when level is SOL_IPV6. func getSockOptIPv6(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name int, outPtr usermem.Addr, outLen int) (marshal.Marshallable, *syserr.Error) { switch name { case linux.IPV6_V6ONLY: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.V6OnlyOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.IPV6_PATHMTU: t.Kernel().EmitUnimplementedEvent(t) case linux.IPV6_TCLASS: // Length handling for parity with Linux. if outLen == 0 { var b primitive.ByteSlice return &b, nil } v, err := ep.GetSockOptInt(tcpip.IPv6TrafficClassOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } uintv := primitive.Uint32(v) // Linux truncates the output binary to outLen. ib := t.CopyScratchBuffer(uintv.SizeBytes()) uintv.MarshalUnsafe(ib) // Handle cases where outLen is lesser than sizeOfInt32. if len(ib) > outLen { ib = ib[:outLen] } ibP := primitive.ByteSlice(ib) return &ibP, nil case linux.IPV6_RECVTCLASS: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.ReceiveTClassOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.IP6T_ORIGINAL_DST: if outLen < int(binary.Size(linux.SockAddrInet6{})) { return nil, syserr.ErrInvalidArgument } var v tcpip.OriginalDestinationOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } a, _ := ConvertAddress(linux.AF_INET6, tcpip.FullAddress(v)) return a.(*linux.SockAddrInet6), nil case linux.IP6T_SO_GET_INFO: if outLen < linux.SizeOfIPTGetinfo { return nil, syserr.ErrInvalidArgument } // Only valid for raw IPv6 sockets. if family, skType, _ := s.Type(); family != linux.AF_INET6 || skType != linux.SOCK_RAW { return nil, syserr.ErrProtocolNotAvailable } stack := inet.StackFromContext(t) if stack == nil { return nil, syserr.ErrNoDevice } info, err := netfilter.GetInfo(t, stack.(*Stack).Stack, outPtr, true) if err != nil { return nil, err } return &info, nil case linux.IP6T_SO_GET_ENTRIES: // IPTGetEntries is reused for IPv6. if outLen < linux.SizeOfIPTGetEntries { return nil, syserr.ErrInvalidArgument } // Only valid for raw IPv6 sockets. if family, skType, _ := s.Type(); family != linux.AF_INET6 || skType != linux.SOCK_RAW { return nil, syserr.ErrProtocolNotAvailable } stack := inet.StackFromContext(t) if stack == nil { return nil, syserr.ErrNoDevice } entries, err := netfilter.GetEntries6(t, stack.(*Stack).Stack, outPtr, outLen) if err != nil { return nil, err } return &entries, nil case linux.IP6T_SO_GET_REVISION_TARGET: if outLen < linux.SizeOfXTGetRevision { return nil, syserr.ErrInvalidArgument } // Only valid for raw IPv6 sockets. if family, skType, _ := s.Type(); family != linux.AF_INET6 || skType != linux.SOCK_RAW { return nil, syserr.ErrProtocolNotAvailable } stack := inet.StackFromContext(t) if stack == nil { return nil, syserr.ErrNoDevice } ret, err := netfilter.TargetRevision(t, outPtr, header.IPv6ProtocolNumber) if err != nil { return nil, err } return &ret, nil default: emitUnimplementedEventIPv6(t, name) } return nil, syserr.ErrProtocolNotAvailable } // getSockOptIP implements GetSockOpt when level is SOL_IP. func getSockOptIP(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name int, outPtr usermem.Addr, outLen int, family int) (marshal.Marshallable, *syserr.Error) { switch name { case linux.IP_TTL: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptInt(tcpip.TTLOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } // Fill in the default value, if needed. vP := primitive.Int32(v) if vP == 0 { vP = DefaultTTL } return &vP, nil case linux.IP_MULTICAST_TTL: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptInt(tcpip.MulticastTTLOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(v) return &vP, nil case linux.IP_MULTICAST_IF: if outLen < len(linux.InetAddr{}) { return nil, syserr.ErrInvalidArgument } var v tcpip.MulticastInterfaceOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } a, _ := ConvertAddress(linux.AF_INET, tcpip.FullAddress{Addr: v.InterfaceAddr}) return &a.(*linux.SockAddrInet).Addr, nil case linux.IP_MULTICAST_LOOP: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.MulticastLoopOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.IP_TOS: // Length handling for parity with Linux. if outLen == 0 { var b primitive.ByteSlice return &b, nil } v, err := ep.GetSockOptInt(tcpip.IPv4TOSOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } if outLen < sizeOfInt32 { vP := primitive.Uint8(v) return &vP, nil } vP := primitive.Int32(v) return &vP, nil case linux.IP_RECVTOS: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.ReceiveTOSOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.IP_PKTINFO: if outLen < sizeOfInt32 { return nil, syserr.ErrInvalidArgument } v, err := ep.GetSockOptBool(tcpip.ReceiveIPPacketInfoOption) if err != nil { return nil, syserr.TranslateNetstackError(err) } vP := primitive.Int32(boolToInt32(v)) return &vP, nil case linux.SO_ORIGINAL_DST: if outLen < int(binary.Size(linux.SockAddrInet{})) { return nil, syserr.ErrInvalidArgument } var v tcpip.OriginalDestinationOption if err := ep.GetSockOpt(&v); err != nil { return nil, syserr.TranslateNetstackError(err) } a, _ := ConvertAddress(linux.AF_INET, tcpip.FullAddress(v)) return a.(*linux.SockAddrInet), nil case linux.IPT_SO_GET_INFO: if outLen < linux.SizeOfIPTGetinfo { return nil, syserr.ErrInvalidArgument } // Only valid for raw IPv4 sockets. if family, skType, _ := s.Type(); family != linux.AF_INET || skType != linux.SOCK_RAW { return nil, syserr.ErrProtocolNotAvailable } stack := inet.StackFromContext(t) if stack == nil { return nil, syserr.ErrNoDevice } info, err := netfilter.GetInfo(t, stack.(*Stack).Stack, outPtr, false) if err != nil { return nil, err } return &info, nil case linux.IPT_SO_GET_ENTRIES: if outLen < linux.SizeOfIPTGetEntries { return nil, syserr.ErrInvalidArgument } // Only valid for raw IPv4 sockets. if family, skType, _ := s.Type(); family != linux.AF_INET || skType != linux.SOCK_RAW { return nil, syserr.ErrProtocolNotAvailable } stack := inet.StackFromContext(t) if stack == nil { return nil, syserr.ErrNoDevice } entries, err := netfilter.GetEntries4(t, stack.(*Stack).Stack, outPtr, outLen) if err != nil { return nil, err } return &entries, nil case linux.IPT_SO_GET_REVISION_TARGET: if outLen < linux.SizeOfXTGetRevision { return nil, syserr.ErrInvalidArgument } // Only valid for raw IPv4 sockets. if family, skType, _ := s.Type(); family != linux.AF_INET || skType != linux.SOCK_RAW { return nil, syserr.ErrProtocolNotAvailable } stack := inet.StackFromContext(t) if stack == nil { return nil, syserr.ErrNoDevice } ret, err := netfilter.TargetRevision(t, outPtr, header.IPv4ProtocolNumber) if err != nil { return nil, err } return &ret, nil default: emitUnimplementedEventIP(t, name) } return nil, syserr.ErrProtocolNotAvailable } // SetSockOpt implements the linux syscall setsockopt(2) for sockets backed by // tcpip.Endpoint. func (s *SocketOperations) SetSockOpt(t *kernel.Task, level int, name int, optVal []byte) *syserr.Error { // TODO(b/78348848): Unlike other socket options, SO_TIMESTAMP is // implemented specifically for netstack.SocketOperations rather than // commonEndpoint. commonEndpoint should be extended to support socket // options where the implementation is not shared, as unix sockets need // their own support for SO_TIMESTAMP. if level == linux.SOL_SOCKET && name == linux.SO_TIMESTAMP { if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } s.readMu.Lock() defer s.readMu.Unlock() s.sockOptTimestamp = usermem.ByteOrder.Uint32(optVal) != 0 return nil } if level == linux.SOL_TCP && name == linux.TCP_INQ { if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } s.readMu.Lock() defer s.readMu.Unlock() s.sockOptInq = usermem.ByteOrder.Uint32(optVal) != 0 return nil } return SetSockOpt(t, s, s.Endpoint, level, name, optVal) } // SetSockOpt can be used to implement the linux syscall setsockopt(2) for // sockets backed by a commonEndpoint. func SetSockOpt(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, level int, name int, optVal []byte) *syserr.Error { switch level { case linux.SOL_SOCKET: return setSockOptSocket(t, s, ep, name, optVal) case linux.SOL_TCP: return setSockOptTCP(t, ep, name, optVal) case linux.SOL_IPV6: return setSockOptIPv6(t, s, ep, name, optVal) case linux.SOL_IP: return setSockOptIP(t, s, ep, name, optVal) case linux.SOL_PACKET: // gVisor doesn't support any SOL_PACKET options just return not // supported. Returning nil here will result in tcpdump thinking AF_PACKET // features are supported and proceed to use them and break. t.Kernel().EmitUnimplementedEvent(t) return syserr.ErrProtocolNotAvailable case linux.SOL_UDP, linux.SOL_ICMPV6, linux.SOL_RAW: t.Kernel().EmitUnimplementedEvent(t) } return nil } // setSockOptSocket implements SetSockOpt when level is SOL_SOCKET. func setSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name int, optVal []byte) *syserr.Error { switch name { case linux.SO_SNDBUF: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.SendBufferSizeOption, int(v))) case linux.SO_RCVBUF: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.ReceiveBufferSizeOption, int(v))) case linux.SO_REUSEADDR: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.ReuseAddressOption, v != 0)) case linux.SO_REUSEPORT: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.ReusePortOption, v != 0)) case linux.SO_BINDTODEVICE: n := bytes.IndexByte(optVal, 0) if n == -1 { n = len(optVal) } name := string(optVal[:n]) if name == "" { v := tcpip.BindToDeviceOption(0) return syserr.TranslateNetstackError(ep.SetSockOpt(&v)) } s := t.NetworkContext() if s == nil { return syserr.ErrNoDevice } for nicID, nic := range s.Interfaces() { if nic.Name == name { v := tcpip.BindToDeviceOption(nicID) return syserr.TranslateNetstackError(ep.SetSockOpt(&v)) } } return syserr.ErrUnknownDevice case linux.SO_BROADCAST: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) ep.SocketOptions().SetBroadcast(v != 0) return nil case linux.SO_PASSCRED: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.PasscredOption, v != 0)) case linux.SO_KEEPALIVE: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.KeepaliveEnabledOption, v != 0)) case linux.SO_SNDTIMEO: if len(optVal) < linux.SizeOfTimeval { return syserr.ErrInvalidArgument } var v linux.Timeval binary.Unmarshal(optVal[:linux.SizeOfTimeval], usermem.ByteOrder, &v) if v.Usec < 0 || v.Usec >= int64(time.Second/time.Microsecond) { return syserr.ErrDomain } s.SetSendTimeout(v.ToNsecCapped()) return nil case linux.SO_RCVTIMEO: if len(optVal) < linux.SizeOfTimeval { return syserr.ErrInvalidArgument } var v linux.Timeval binary.Unmarshal(optVal[:linux.SizeOfTimeval], usermem.ByteOrder, &v) if v.Usec < 0 || v.Usec >= int64(time.Second/time.Microsecond) { return syserr.ErrDomain } s.SetRecvTimeout(v.ToNsecCapped()) return nil case linux.SO_OOBINLINE: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) if v == 0 { socket.SetSockOptEmitUnimplementedEvent(t, name) } opt := tcpip.OutOfBandInlineOption(v) return syserr.TranslateNetstackError(ep.SetSockOpt(&opt)) case linux.SO_NO_CHECK: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.NoChecksumOption, v != 0)) case linux.SO_LINGER: if len(optVal) < linux.SizeOfLinger { return syserr.ErrInvalidArgument } var v linux.Linger binary.Unmarshal(optVal[:linux.SizeOfLinger], usermem.ByteOrder, &v) if v != (linux.Linger{}) { socket.SetSockOptEmitUnimplementedEvent(t, name) } return syserr.TranslateNetstackError( ep.SetSockOpt(&tcpip.LingerOption{ Enabled: v.OnOff != 0, Timeout: time.Second * time.Duration(v.Linger)})) case linux.SO_DETACH_FILTER: // optval is ignored. var v tcpip.SocketDetachFilterOption return syserr.TranslateNetstackError(ep.SetSockOpt(&v)) default: socket.SetSockOptEmitUnimplementedEvent(t, name) } return nil } // setSockOptTCP implements SetSockOpt when level is SOL_TCP. func setSockOptTCP(t *kernel.Task, ep commonEndpoint, name int, optVal []byte) *syserr.Error { switch name { case linux.TCP_NODELAY: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.DelayOption, v == 0)) case linux.TCP_CORK: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.CorkOption, v != 0)) case linux.TCP_QUICKACK: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.QuickAckOption, v != 0)) case linux.TCP_MAXSEG: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.MaxSegOption, int(v))) case linux.TCP_KEEPIDLE: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) if v < 1 || v > linux.MAX_TCP_KEEPIDLE { return syserr.ErrInvalidArgument } opt := tcpip.KeepaliveIdleOption(time.Second * time.Duration(v)) return syserr.TranslateNetstackError(ep.SetSockOpt(&opt)) case linux.TCP_KEEPINTVL: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) if v < 1 || v > linux.MAX_TCP_KEEPINTVL { return syserr.ErrInvalidArgument } opt := tcpip.KeepaliveIntervalOption(time.Second * time.Duration(v)) return syserr.TranslateNetstackError(ep.SetSockOpt(&opt)) case linux.TCP_KEEPCNT: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) if v < 1 || v > linux.MAX_TCP_KEEPCNT { return syserr.ErrInvalidArgument } return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.KeepaliveCountOption, int(v))) case linux.TCP_USER_TIMEOUT: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := int32(usermem.ByteOrder.Uint32(optVal)) if v < 0 { return syserr.ErrInvalidArgument } opt := tcpip.TCPUserTimeoutOption(time.Millisecond * time.Duration(v)) return syserr.TranslateNetstackError(ep.SetSockOpt(&opt)) case linux.TCP_CONGESTION: v := tcpip.CongestionControlOption(optVal) if err := ep.SetSockOpt(&v); err != nil { return syserr.TranslateNetstackError(err) } return nil case linux.TCP_LINGER2: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := int32(usermem.ByteOrder.Uint32(optVal)) opt := tcpip.TCPLingerTimeoutOption(time.Second * time.Duration(v)) return syserr.TranslateNetstackError(ep.SetSockOpt(&opt)) case linux.TCP_DEFER_ACCEPT: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := int32(usermem.ByteOrder.Uint32(optVal)) if v < 0 { v = 0 } opt := tcpip.TCPDeferAcceptOption(time.Second * time.Duration(v)) return syserr.TranslateNetstackError(ep.SetSockOpt(&opt)) case linux.TCP_SYNCNT: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.TCPSynCountOption, int(v))) case linux.TCP_WINDOW_CLAMP: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.TCPWindowClampOption, int(v))) case linux.TCP_REPAIR_OPTIONS: t.Kernel().EmitUnimplementedEvent(t) default: emitUnimplementedEventTCP(t, name) } return nil } // setSockOptIPv6 implements SetSockOpt when level is SOL_IPV6. func setSockOptIPv6(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name int, optVal []byte) *syserr.Error { switch name { case linux.IPV6_V6ONLY: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := usermem.ByteOrder.Uint32(optVal) return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.V6OnlyOption, v != 0)) case linux.IPV6_ADD_MEMBERSHIP, linux.IPV6_DROP_MEMBERSHIP, linux.IPV6_IPSEC_POLICY, linux.IPV6_JOIN_ANYCAST, linux.IPV6_LEAVE_ANYCAST, // TODO(b/148887420): Add support for IPV6_PKTINFO. linux.IPV6_PKTINFO, linux.IPV6_ROUTER_ALERT, linux.IPV6_XFRM_POLICY, linux.MCAST_BLOCK_SOURCE, linux.MCAST_JOIN_GROUP, linux.MCAST_JOIN_SOURCE_GROUP, linux.MCAST_LEAVE_GROUP, linux.MCAST_LEAVE_SOURCE_GROUP, linux.MCAST_UNBLOCK_SOURCE: t.Kernel().EmitUnimplementedEvent(t) case linux.IPV6_TCLASS: if len(optVal) < sizeOfInt32 { return syserr.ErrInvalidArgument } v := int32(usermem.ByteOrder.Uint32(optVal)) if v < -1 || v > 255 { return syserr.ErrInvalidArgument } if v == -1 { v = 0 } return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.IPv6TrafficClassOption, int(v))) case linux.IPV6_RECVTCLASS: v, err := parseIntOrChar(optVal) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.ReceiveTClassOption, v != 0)) case linux.IP6T_SO_SET_REPLACE: if len(optVal) < linux.SizeOfIP6TReplace { return syserr.ErrInvalidArgument } // Only valid for raw IPv6 sockets. if family, skType, _ := s.Type(); family != linux.AF_INET6 || skType != linux.SOCK_RAW { return syserr.ErrProtocolNotAvailable } stack := inet.StackFromContext(t) if stack == nil { return syserr.ErrNoDevice } // Stack must be a netstack stack. return netfilter.SetEntries(stack.(*Stack).Stack, optVal, true) case linux.IP6T_SO_SET_ADD_COUNTERS: // TODO(gvisor.dev/issue/170): Counter support. return nil default: emitUnimplementedEventIPv6(t, name) } return nil } var ( inetMulticastRequestSize = int(binary.Size(linux.InetMulticastRequest{})) inetMulticastRequestWithNICSize = int(binary.Size(linux.InetMulticastRequestWithNIC{})) ) // copyInMulticastRequest copies in a variable-size multicast request. The // kernel determines which structure was passed by its length. IP_MULTICAST_IF // supports ip_mreqn, ip_mreq and in_addr, while IP_ADD_MEMBERSHIP and // IP_DROP_MEMBERSHIP only support ip_mreqn and ip_mreq. To handle this, // allowAddr controls whether in_addr is accepted or rejected. func copyInMulticastRequest(optVal []byte, allowAddr bool) (linux.InetMulticastRequestWithNIC, *syserr.Error) { if len(optVal) < len(linux.InetAddr{}) { return linux.InetMulticastRequestWithNIC{}, syserr.ErrInvalidArgument } if len(optVal) < inetMulticastRequestSize { if !allowAddr { return linux.InetMulticastRequestWithNIC{}, syserr.ErrInvalidArgument } var req linux.InetMulticastRequestWithNIC copy(req.InterfaceAddr[:], optVal) return req, nil } if len(optVal) >= inetMulticastRequestWithNICSize { var req linux.InetMulticastRequestWithNIC binary.Unmarshal(optVal[:inetMulticastRequestWithNICSize], usermem.ByteOrder, &req) return req, nil } var req linux.InetMulticastRequestWithNIC binary.Unmarshal(optVal[:inetMulticastRequestSize], usermem.ByteOrder, &req.InetMulticastRequest) return req, nil } // parseIntOrChar copies either a 32-bit int or an 8-bit uint out of buf. // // net/ipv4/ip_sockglue.c:do_ip_setsockopt does this for its socket options. func parseIntOrChar(buf []byte) (int32, *syserr.Error) { if len(buf) == 0 { return 0, syserr.ErrInvalidArgument } if len(buf) >= sizeOfInt32 { return int32(usermem.ByteOrder.Uint32(buf)), nil } return int32(buf[0]), nil } // setSockOptIP implements SetSockOpt when level is SOL_IP. func setSockOptIP(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, name int, optVal []byte) *syserr.Error { switch name { case linux.IP_MULTICAST_TTL: v, err := parseIntOrChar(optVal) if err != nil { return err } if v == -1 { // Linux translates -1 to 1. v = 1 } if v < 0 || v > 255 { return syserr.ErrInvalidArgument } return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.MulticastTTLOption, int(v))) case linux.IP_ADD_MEMBERSHIP: req, err := copyInMulticastRequest(optVal, false /* allowAddr */) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOpt(&tcpip.AddMembershipOption{ NIC: tcpip.NICID(req.InterfaceIndex), // TODO(igudger): Change AddMembership to use the standard // any address representation. InterfaceAddr: tcpip.Address(req.InterfaceAddr[:]), MulticastAddr: tcpip.Address(req.MulticastAddr[:]), })) case linux.IP_DROP_MEMBERSHIP: req, err := copyInMulticastRequest(optVal, false /* allowAddr */) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOpt(&tcpip.RemoveMembershipOption{ NIC: tcpip.NICID(req.InterfaceIndex), // TODO(igudger): Change DropMembership to use the standard // any address representation. InterfaceAddr: tcpip.Address(req.InterfaceAddr[:]), MulticastAddr: tcpip.Address(req.MulticastAddr[:]), })) case linux.IP_MULTICAST_IF: req, err := copyInMulticastRequest(optVal, true /* allowAddr */) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOpt(&tcpip.MulticastInterfaceOption{ NIC: tcpip.NICID(req.InterfaceIndex), InterfaceAddr: bytesToIPAddress(req.InterfaceAddr[:]), })) case linux.IP_MULTICAST_LOOP: v, err := parseIntOrChar(optVal) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.MulticastLoopOption, v != 0)) case linux.MCAST_JOIN_GROUP: // FIXME(b/124219304): Implement MCAST_JOIN_GROUP. t.Kernel().EmitUnimplementedEvent(t) return syserr.ErrInvalidArgument case linux.IP_TTL: v, err := parseIntOrChar(optVal) if err != nil { return err } // -1 means default TTL. if v == -1 { v = 0 } else if v < 1 || v > 255 { return syserr.ErrInvalidArgument } return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.TTLOption, int(v))) case linux.IP_TOS: if len(optVal) == 0 { return nil } v, err := parseIntOrChar(optVal) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOptInt(tcpip.IPv4TOSOption, int(v))) case linux.IP_RECVTOS: v, err := parseIntOrChar(optVal) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.ReceiveTOSOption, v != 0)) case linux.IP_PKTINFO: if len(optVal) == 0 { return nil } v, err := parseIntOrChar(optVal) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.ReceiveIPPacketInfoOption, v != 0)) case linux.IP_HDRINCL: if len(optVal) == 0 { return nil } v, err := parseIntOrChar(optVal) if err != nil { return err } return syserr.TranslateNetstackError(ep.SetSockOptBool(tcpip.IPHdrIncludedOption, v != 0)) case linux.IPT_SO_SET_REPLACE: if len(optVal) < linux.SizeOfIPTReplace { return syserr.ErrInvalidArgument } // Only valid for raw IPv4 sockets. if family, skType, _ := s.Type(); family != linux.AF_INET || skType != linux.SOCK_RAW { return syserr.ErrProtocolNotAvailable } stack := inet.StackFromContext(t) if stack == nil { return syserr.ErrNoDevice } // Stack must be a netstack stack. return netfilter.SetEntries(stack.(*Stack).Stack, optVal, false) case linux.IPT_SO_SET_ADD_COUNTERS: // TODO(gvisor.dev/issue/170): Counter support. return nil case linux.IP_ADD_SOURCE_MEMBERSHIP, linux.IP_BIND_ADDRESS_NO_PORT, linux.IP_BLOCK_SOURCE, linux.IP_CHECKSUM, linux.IP_DROP_SOURCE_MEMBERSHIP, linux.IP_FREEBIND, linux.IP_IPSEC_POLICY, linux.IP_MINTTL, linux.IP_MSFILTER, linux.IP_MTU_DISCOVER, linux.IP_MULTICAST_ALL, linux.IP_NODEFRAG, linux.IP_OPTIONS, linux.IP_PASSSEC, linux.IP_RECVERR, linux.IP_RECVFRAGSIZE, linux.IP_RECVOPTS, linux.IP_RECVORIGDSTADDR, linux.IP_RECVTTL, linux.IP_RETOPTS, linux.IP_TRANSPARENT, linux.IP_UNBLOCK_SOURCE, linux.IP_UNICAST_IF, linux.IP_XFRM_POLICY, linux.MCAST_BLOCK_SOURCE, linux.MCAST_JOIN_SOURCE_GROUP, linux.MCAST_LEAVE_GROUP, linux.MCAST_LEAVE_SOURCE_GROUP, linux.MCAST_MSFILTER, linux.MCAST_UNBLOCK_SOURCE: t.Kernel().EmitUnimplementedEvent(t) } return nil } // emitUnimplementedEventTCP emits unimplemented event if name is valid. This // function contains names that are common between Get and SetSockOpt when // level is SOL_TCP. func emitUnimplementedEventTCP(t *kernel.Task, name int) { switch name { case linux.TCP_CONGESTION, linux.TCP_CORK, linux.TCP_FASTOPEN, linux.TCP_FASTOPEN_CONNECT, linux.TCP_FASTOPEN_KEY, linux.TCP_FASTOPEN_NO_COOKIE, linux.TCP_QUEUE_SEQ, linux.TCP_REPAIR, linux.TCP_REPAIR_QUEUE, linux.TCP_REPAIR_WINDOW, linux.TCP_SAVED_SYN, linux.TCP_SAVE_SYN, linux.TCP_THIN_DUPACK, linux.TCP_THIN_LINEAR_TIMEOUTS, linux.TCP_TIMESTAMP, linux.TCP_ULP: t.Kernel().EmitUnimplementedEvent(t) } } // emitUnimplementedEventIPv6 emits unimplemented event if name is valid. It // contains names that are common between Get and SetSockOpt when level is // SOL_IPV6. func emitUnimplementedEventIPv6(t *kernel.Task, name int) { switch name { case linux.IPV6_2292DSTOPTS, linux.IPV6_2292HOPLIMIT, linux.IPV6_2292HOPOPTS, linux.IPV6_2292PKTINFO, linux.IPV6_2292PKTOPTIONS, linux.IPV6_2292RTHDR, linux.IPV6_ADDR_PREFERENCES, linux.IPV6_AUTOFLOWLABEL, linux.IPV6_DONTFRAG, linux.IPV6_DSTOPTS, linux.IPV6_FLOWINFO, linux.IPV6_FLOWINFO_SEND, linux.IPV6_FLOWLABEL_MGR, linux.IPV6_FREEBIND, linux.IPV6_HOPOPTS, linux.IPV6_MINHOPCOUNT, linux.IPV6_MTU, linux.IPV6_MTU_DISCOVER, linux.IPV6_MULTICAST_ALL, linux.IPV6_MULTICAST_HOPS, linux.IPV6_MULTICAST_IF, linux.IPV6_MULTICAST_LOOP, linux.IPV6_RECVDSTOPTS, linux.IPV6_RECVERR, linux.IPV6_RECVFRAGSIZE, linux.IPV6_RECVHOPLIMIT, linux.IPV6_RECVHOPOPTS, linux.IPV6_RECVORIGDSTADDR, linux.IPV6_RECVPATHMTU, linux.IPV6_RECVPKTINFO, linux.IPV6_RECVRTHDR, linux.IPV6_RTHDR, linux.IPV6_RTHDRDSTOPTS, linux.IPV6_TCLASS, linux.IPV6_TRANSPARENT, linux.IPV6_UNICAST_HOPS, linux.IPV6_UNICAST_IF, linux.MCAST_MSFILTER, linux.IPV6_ADDRFORM: t.Kernel().EmitUnimplementedEvent(t) } } // emitUnimplementedEventIP emits unimplemented event if name is valid. It // contains names that are common between Get and SetSockOpt when level is // SOL_IP. func emitUnimplementedEventIP(t *kernel.Task, name int) { switch name { case linux.IP_TOS, linux.IP_TTL, linux.IP_HDRINCL, linux.IP_OPTIONS, linux.IP_ROUTER_ALERT, linux.IP_RECVOPTS, linux.IP_RETOPTS, linux.IP_PKTINFO, linux.IP_PKTOPTIONS, linux.IP_MTU_DISCOVER, linux.IP_RECVERR, linux.IP_RECVTTL, linux.IP_RECVTOS, linux.IP_MTU, linux.IP_FREEBIND, linux.IP_IPSEC_POLICY, linux.IP_XFRM_POLICY, linux.IP_PASSSEC, linux.IP_TRANSPARENT, linux.IP_ORIGDSTADDR, linux.IP_MINTTL, linux.IP_NODEFRAG, linux.IP_CHECKSUM, linux.IP_BIND_ADDRESS_NO_PORT, linux.IP_RECVFRAGSIZE, linux.IP_MULTICAST_IF, linux.IP_MULTICAST_TTL, linux.IP_MULTICAST_LOOP, linux.IP_ADD_MEMBERSHIP, linux.IP_DROP_MEMBERSHIP, linux.IP_UNBLOCK_SOURCE, linux.IP_BLOCK_SOURCE, linux.IP_ADD_SOURCE_MEMBERSHIP, linux.IP_DROP_SOURCE_MEMBERSHIP, linux.IP_MSFILTER, linux.MCAST_JOIN_GROUP, linux.MCAST_BLOCK_SOURCE, linux.MCAST_UNBLOCK_SOURCE, linux.MCAST_LEAVE_GROUP, linux.MCAST_JOIN_SOURCE_GROUP, linux.MCAST_LEAVE_SOURCE_GROUP, linux.MCAST_MSFILTER, linux.IP_MULTICAST_ALL, linux.IP_UNICAST_IF: t.Kernel().EmitUnimplementedEvent(t) } } // isLinkLocal determines if the given IPv6 address is link-local. This is the // case when it has the fe80::/10 prefix. This check is used to determine when // the NICID is relevant for a given IPv6 address. func isLinkLocal(addr tcpip.Address) bool { return len(addr) >= 2 && addr[0] == 0xfe && addr[1]&0xc0 == 0x80 } // ConvertAddress converts the given address to a native format. func ConvertAddress(family int, addr tcpip.FullAddress) (linux.SockAddr, uint32) { switch family { case linux.AF_UNIX: var out linux.SockAddrUnix out.Family = linux.AF_UNIX l := len([]byte(addr.Addr)) for i := 0; i < l; i++ { out.Path[i] = int8(addr.Addr[i]) } // Linux returns the used length of the address struct (including the // null terminator) for filesystem paths. The Family field is 2 bytes. // It is sometimes allowed to exclude the null terminator if the // address length is the max. Abstract and empty paths always return // the full exact length. if l == 0 || out.Path[0] == 0 || l == len(out.Path) { return &out, uint32(2 + l) } return &out, uint32(3 + l) case linux.AF_INET: var out linux.SockAddrInet copy(out.Addr[:], addr.Addr) out.Family = linux.AF_INET out.Port = htons(addr.Port) return &out, uint32(sockAddrInetSize) case linux.AF_INET6: var out linux.SockAddrInet6 if len(addr.Addr) == header.IPv4AddressSize { // Copy address in v4-mapped format. copy(out.Addr[12:], addr.Addr) out.Addr[10] = 0xff out.Addr[11] = 0xff } else { copy(out.Addr[:], addr.Addr) } out.Family = linux.AF_INET6 out.Port = htons(addr.Port) if isLinkLocal(addr.Addr) { out.Scope_id = uint32(addr.NIC) } return &out, uint32(sockAddrInet6Size) case linux.AF_PACKET: // TODO(gvisor.dev/issue/173): Return protocol too. var out linux.SockAddrLink out.Family = linux.AF_PACKET out.InterfaceIndex = int32(addr.NIC) out.HardwareAddrLen = header.EthernetAddressSize copy(out.HardwareAddr[:], addr.Addr) return &out, uint32(sockAddrLinkSize) default: return nil, 0 } } // GetSockName implements the linux syscall getsockname(2) for sockets backed by // tcpip.Endpoint. func (s *socketOpsCommon) GetSockName(t *kernel.Task) (linux.SockAddr, uint32, *syserr.Error) { addr, err := s.Endpoint.GetLocalAddress() if err != nil { return nil, 0, syserr.TranslateNetstackError(err) } a, l := ConvertAddress(s.family, addr) return a, l, nil } // GetPeerName implements the linux syscall getpeername(2) for sockets backed by // tcpip.Endpoint. func (s *socketOpsCommon) GetPeerName(t *kernel.Task) (linux.SockAddr, uint32, *syserr.Error) { addr, err := s.Endpoint.GetRemoteAddress() if err != nil { return nil, 0, syserr.TranslateNetstackError(err) } a, l := ConvertAddress(s.family, addr) return a, l, nil } // coalescingRead is the fast path for non-blocking, non-peek, stream-based // case. It coalesces as many packets as possible before returning to the // caller. // // Precondition: s.readMu must be locked. func (s *socketOpsCommon) coalescingRead(ctx context.Context, dst usermem.IOSequence, discard bool) (int, *syserr.Error) { var err *syserr.Error var copied int // Copy as many views as possible into the user-provided buffer. for { // Always do at least one fetchReadView, even if the number of bytes to // read is 0. err = s.fetchReadView() if err != nil || len(s.readView) == 0 { break } if dst.NumBytes() == 0 { break } var n int var e error if discard { n = len(s.readView) if int64(n) > dst.NumBytes() { n = int(dst.NumBytes()) } } else { n, e = dst.CopyOut(ctx, s.readView) // Set the control message, even if 0 bytes were read. if e == nil { s.updateTimestamp() } } copied += n s.readView.TrimFront(n) dst = dst.DropFirst(n) if e != nil { err = syserr.FromError(e) break } // If we are done reading requested data then stop. if dst.NumBytes() == 0 { break } } if len(s.readView) == 0 { atomic.StoreUint32(&s.readViewHasData, 0) } // If we managed to copy something, we must deliver it. if copied > 0 { s.Endpoint.ModerateRecvBuf(copied) return copied, nil } return 0, err } func (s *socketOpsCommon) fillCmsgInq(cmsg *socket.ControlMessages) { if !s.sockOptInq { return } rcvBufUsed, err := s.Endpoint.GetSockOptInt(tcpip.ReceiveQueueSizeOption) if err != nil { return } cmsg.IP.HasInq = true cmsg.IP.Inq = int32(len(s.readView) + rcvBufUsed) } func toLinuxPacketType(pktType tcpip.PacketType) uint8 { switch pktType { case tcpip.PacketHost: return linux.PACKET_HOST case tcpip.PacketOtherHost: return linux.PACKET_OTHERHOST case tcpip.PacketOutgoing: return linux.PACKET_OUTGOING case tcpip.PacketBroadcast: return linux.PACKET_BROADCAST case tcpip.PacketMulticast: return linux.PACKET_MULTICAST default: panic(fmt.Sprintf("unknown packet type: %d", pktType)) } } // nonBlockingRead issues a non-blocking read. // // TODO(b/78348848): Support timestamps for stream sockets. func (s *socketOpsCommon) nonBlockingRead(ctx context.Context, dst usermem.IOSequence, peek, trunc, senderRequested bool) (int, int, linux.SockAddr, uint32, socket.ControlMessages, *syserr.Error) { isPacket := s.isPacketBased() // Fast path for regular reads from stream (e.g., TCP) endpoints. Note // that senderRequested is ignored for stream sockets. if !peek && !isPacket { // TCP sockets discard the data if MSG_TRUNC is set. // // This behavior is documented in man 7 tcp: // Since version 2.4, Linux supports the use of MSG_TRUNC in the flags // argument of recv(2) (and recvmsg(2)). This flag causes the received // bytes of data to be discarded, rather than passed back in a // caller-supplied buffer. s.readMu.Lock() n, err := s.coalescingRead(ctx, dst, trunc) cmsg := s.controlMessages() s.fillCmsgInq(&cmsg) s.readMu.Unlock() return n, 0, nil, 0, cmsg, err } s.readMu.Lock() defer s.readMu.Unlock() if err := s.fetchReadView(); err != nil { return 0, 0, nil, 0, socket.ControlMessages{}, err } if !isPacket && peek && trunc { // MSG_TRUNC with MSG_PEEK on a TCP socket returns the // amount that could be read. rql, err := s.Endpoint.GetSockOptInt(tcpip.ReceiveQueueSizeOption) if err != nil { return 0, 0, nil, 0, socket.ControlMessages{}, syserr.TranslateNetstackError(err) } available := len(s.readView) + int(rql) bufLen := int(dst.NumBytes()) if available < bufLen { return available, 0, nil, 0, socket.ControlMessages{}, nil } return bufLen, 0, nil, 0, socket.ControlMessages{}, nil } n, err := dst.CopyOut(ctx, s.readView) // Set the control message, even if 0 bytes were read. if err == nil { s.updateTimestamp() } var addr linux.SockAddr var addrLen uint32 if isPacket && senderRequested { addr, addrLen = ConvertAddress(s.family, s.sender) switch v := addr.(type) { case *linux.SockAddrLink: v.Protocol = htons(uint16(s.linkPacketInfo.Protocol)) v.PacketType = toLinuxPacketType(s.linkPacketInfo.PktType) } } if peek { if l := len(s.readView); trunc && l > n { // isPacket must be true. return l, linux.MSG_TRUNC, addr, addrLen, s.controlMessages(), syserr.FromError(err) } if isPacket || err != nil { return n, 0, addr, addrLen, s.controlMessages(), syserr.FromError(err) } // We need to peek beyond the first message. dst = dst.DropFirst(n) num, err := dst.CopyOutFrom(ctx, safemem.FromVecReaderFunc{func(dsts [][]byte) (int64, error) { n, _, err := s.Endpoint.Peek(dsts) // TODO(b/78348848): Handle peek timestamp. if err != nil { return int64(n), syserr.TranslateNetstackError(err).ToError() } return int64(n), nil }}) n += int(num) if err == syserror.ErrWouldBlock && n > 0 { // We got some data, so no need to return an error. err = nil } return n, 0, nil, 0, s.controlMessages(), syserr.FromError(err) } var msgLen int if isPacket { msgLen = len(s.readView) s.readView = nil } else { msgLen = int(n) s.readView.TrimFront(int(n)) } if len(s.readView) == 0 { atomic.StoreUint32(&s.readViewHasData, 0) } var flags int if msgLen > int(n) { flags |= linux.MSG_TRUNC } if trunc { n = msgLen } cmsg := s.controlMessages() s.fillCmsgInq(&cmsg) return n, flags, addr, addrLen, cmsg, syserr.FromError(err) } func (s *socketOpsCommon) controlMessages() socket.ControlMessages { return socket.ControlMessages{ IP: tcpip.ControlMessages{ HasTimestamp: s.readCM.HasTimestamp && s.sockOptTimestamp, Timestamp: s.readCM.Timestamp, HasTOS: s.readCM.HasTOS, TOS: s.readCM.TOS, HasTClass: s.readCM.HasTClass, TClass: s.readCM.TClass, HasIPPacketInfo: s.readCM.HasIPPacketInfo, PacketInfo: s.readCM.PacketInfo, }, } } // updateTimestamp sets the timestamp for SIOCGSTAMP. It should be called after // successfully writing packet data out to userspace. // // Precondition: s.readMu must be locked. func (s *socketOpsCommon) updateTimestamp() { // Save the SIOCGSTAMP timestamp only if SO_TIMESTAMP is disabled. if !s.sockOptTimestamp { s.timestampValid = true s.timestampNS = s.readCM.Timestamp } } // RecvMsg implements the linux syscall recvmsg(2) for sockets backed by // tcpip.Endpoint. func (s *socketOpsCommon) RecvMsg(t *kernel.Task, dst usermem.IOSequence, flags int, haveDeadline bool, deadline ktime.Time, senderRequested bool, controlDataLen uint64) (n int, msgFlags int, senderAddr linux.SockAddr, senderAddrLen uint32, controlMessages socket.ControlMessages, err *syserr.Error) { trunc := flags&linux.MSG_TRUNC != 0 peek := flags&linux.MSG_PEEK != 0 dontWait := flags&linux.MSG_DONTWAIT != 0 waitAll := flags&linux.MSG_WAITALL != 0 if senderRequested && !s.isPacketBased() { // Stream sockets ignore the sender address. senderRequested = false } n, msgFlags, senderAddr, senderAddrLen, controlMessages, err = s.nonBlockingRead(t, dst, peek, trunc, senderRequested) if s.isPacketBased() && err == syserr.ErrClosedForReceive && flags&linux.MSG_DONTWAIT != 0 { // In this situation we should return EAGAIN. return 0, 0, nil, 0, socket.ControlMessages{}, syserr.ErrTryAgain } if err != nil && (err != syserr.ErrWouldBlock || dontWait) { // Read failed and we should not retry. return 0, 0, nil, 0, socket.ControlMessages{}, err } if err == nil && (dontWait || !waitAll || s.isPacketBased() || int64(n) >= dst.NumBytes()) { // We got all the data we need. return } // Don't overwrite any data we received. dst = dst.DropFirst(n) // We'll have to block. Register for notifications and keep trying to // send all the data. e, ch := waiter.NewChannelEntry(nil) s.EventRegister(&e, waiter.EventIn) defer s.EventUnregister(&e) for { var rn int rn, msgFlags, senderAddr, senderAddrLen, controlMessages, err = s.nonBlockingRead(t, dst, peek, trunc, senderRequested) n += rn if err != nil && err != syserr.ErrWouldBlock { // Always stop on errors other than would block as we generally // won't be able to get any more data. Eat the error if we got // any data. if n > 0 { err = nil } return } if err == nil && (s.isPacketBased() || !waitAll || int64(rn) >= dst.NumBytes()) { // We got all the data we need. return } dst = dst.DropFirst(rn) if err := t.BlockWithDeadline(ch, haveDeadline, deadline); err != nil { if n > 0 { return n, msgFlags, senderAddr, senderAddrLen, controlMessages, nil } if err == syserror.ETIMEDOUT { return 0, 0, nil, 0, socket.ControlMessages{}, syserr.ErrTryAgain } return 0, 0, nil, 0, socket.ControlMessages{}, syserr.FromError(err) } } } // SendMsg implements the linux syscall sendmsg(2) for sockets backed by // tcpip.Endpoint. func (s *socketOpsCommon) SendMsg(t *kernel.Task, src usermem.IOSequence, to []byte, flags int, haveDeadline bool, deadline ktime.Time, controlMessages socket.ControlMessages) (int, *syserr.Error) { // Reject Unix control messages. if !controlMessages.Unix.Empty() { return 0, syserr.ErrInvalidArgument } var addr *tcpip.FullAddress if len(to) > 0 { addrBuf, family, err := AddressAndFamily(to) if err != nil { return 0, err } if err := s.checkFamily(family, false /* exact */); err != nil { return 0, err } addrBuf = s.mapFamily(addrBuf, family) addr = &addrBuf } opts := tcpip.WriteOptions{ To: addr, More: flags&linux.MSG_MORE != 0, EndOfRecord: flags&linux.MSG_EOR != 0, } v := &ioSequencePayload{t, src} n, resCh, err := s.Endpoint.Write(v, opts) if resCh != nil { if err := t.Block(resCh); err != nil { return 0, syserr.FromError(err) } n, _, err = s.Endpoint.Write(v, opts) } dontWait := flags&linux.MSG_DONTWAIT != 0 if err == nil && (n >= v.src.NumBytes() || dontWait) { // Complete write. return int(n), nil } if err != nil && (err != tcpip.ErrWouldBlock || dontWait) { return int(n), syserr.TranslateNetstackError(err) } // We'll have to block. Register for notification and keep trying to // send all the data. e, ch := waiter.NewChannelEntry(nil) s.EventRegister(&e, waiter.EventOut) defer s.EventUnregister(&e) v.DropFirst(int(n)) total := n for { n, _, err = s.Endpoint.Write(v, opts) v.DropFirst(int(n)) total += n if err != nil && err != tcpip.ErrWouldBlock && total == 0 { return 0, syserr.TranslateNetstackError(err) } if err == nil && v.src.NumBytes() == 0 || err != nil && err != tcpip.ErrWouldBlock { return int(total), nil } if err := t.BlockWithDeadline(ch, haveDeadline, deadline); err != nil { if err == syserror.ETIMEDOUT { return int(total), syserr.ErrTryAgain } // handleIOError will consume errors from t.Block if needed. return int(total), syserr.FromError(err) } } } // Ioctl implements fs.FileOperations.Ioctl. func (s *SocketOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) { return s.socketOpsCommon.ioctl(ctx, io, args) } func (s *socketOpsCommon) ioctl(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) { t := kernel.TaskFromContext(ctx) if t == nil { panic("ioctl(2) may only be called from a task goroutine") } // SIOCGSTAMP is implemented by netstack rather than all commonEndpoint // sockets. // TODO(b/78348848): Add a commonEndpoint method to support SIOCGSTAMP. switch args[1].Int() { case linux.SIOCGSTAMP: s.readMu.Lock() defer s.readMu.Unlock() if !s.timestampValid { return 0, syserror.ENOENT } tv := linux.NsecToTimeval(s.timestampNS) _, err := tv.CopyOut(t, args[2].Pointer()) return 0, err case linux.TIOCINQ: v, terr := s.Endpoint.GetSockOptInt(tcpip.ReceiveQueueSizeOption) if terr != nil { return 0, syserr.TranslateNetstackError(terr).ToError() } // Add bytes removed from the endpoint but not yet sent to the caller. s.readMu.Lock() v += len(s.readView) s.readMu.Unlock() if v > math.MaxInt32 { v = math.MaxInt32 } // Copy result to userspace. vP := primitive.Int32(v) _, err := vP.CopyOut(t, args[2].Pointer()) return 0, err } return Ioctl(ctx, s.Endpoint, io, args) } // Ioctl performs a socket ioctl. func Ioctl(ctx context.Context, ep commonEndpoint, io usermem.IO, args arch.SyscallArguments) (uintptr, error) { t := kernel.TaskFromContext(ctx) if t == nil { panic("ioctl(2) may only be called from a task goroutine") } switch arg := int(args[1].Int()); arg { case linux.SIOCGIFFLAGS, linux.SIOCGIFADDR, linux.SIOCGIFBRDADDR, linux.SIOCGIFDSTADDR, linux.SIOCGIFHWADDR, linux.SIOCGIFINDEX, linux.SIOCGIFMAP, linux.SIOCGIFMETRIC, linux.SIOCGIFMTU, linux.SIOCGIFNAME, linux.SIOCGIFNETMASK, linux.SIOCGIFTXQLEN, linux.SIOCETHTOOL: var ifr linux.IFReq if _, err := ifr.CopyIn(t, args[2].Pointer()); err != nil { return 0, err } if err := interfaceIoctl(ctx, io, arg, &ifr); err != nil { return 0, err.ToError() } _, err := ifr.CopyOut(t, args[2].Pointer()) return 0, err case linux.SIOCGIFCONF: // Return a list of interface addresses or the buffer size // necessary to hold the list. var ifc linux.IFConf if _, err := ifc.CopyIn(t, args[2].Pointer()); err != nil { return 0, err } if err := ifconfIoctl(ctx, t, io, &ifc); err != nil { return 0, err } _, err := ifc.CopyOut(t, args[2].Pointer()) return 0, err case linux.TIOCINQ: v, terr := ep.GetSockOptInt(tcpip.ReceiveQueueSizeOption) if terr != nil { return 0, syserr.TranslateNetstackError(terr).ToError() } if v > math.MaxInt32 { v = math.MaxInt32 } // Copy result to userspace. vP := primitive.Int32(v) _, err := vP.CopyOut(t, args[2].Pointer()) return 0, err case linux.TIOCOUTQ: v, terr := ep.GetSockOptInt(tcpip.SendQueueSizeOption) if terr != nil { return 0, syserr.TranslateNetstackError(terr).ToError() } if v > math.MaxInt32 { v = math.MaxInt32 } // Copy result to userspace. vP := primitive.Int32(v) _, err := vP.CopyOut(t, args[2].Pointer()) return 0, err case linux.SIOCGIFMEM, linux.SIOCGIFPFLAGS, linux.SIOCGMIIPHY, linux.SIOCGMIIREG: unimpl.EmitUnimplementedEvent(ctx) } return 0, syserror.ENOTTY } // interfaceIoctl implements interface requests. func interfaceIoctl(ctx context.Context, io usermem.IO, arg int, ifr *linux.IFReq) *syserr.Error { var ( iface inet.Interface index int32 found bool ) // Find the relevant device. stack := inet.StackFromContext(ctx) if stack == nil { return syserr.ErrNoDevice } // SIOCGIFNAME uses ifr.ifr_ifindex rather than ifr.ifr_name to // identify a device. if arg == linux.SIOCGIFNAME { // Gets the name of the interface given the interface index // stored in ifr_ifindex. index = int32(usermem.ByteOrder.Uint32(ifr.Data[:4])) if iface, ok := stack.Interfaces()[index]; ok { ifr.SetName(iface.Name) return nil } return syserr.ErrNoDevice } // Find the relevant device. for index, iface = range stack.Interfaces() { if iface.Name == ifr.Name() { found = true break } } if !found { return syserr.ErrNoDevice } switch arg { case linux.SIOCGIFINDEX: // Copy out the index to the data. usermem.ByteOrder.PutUint32(ifr.Data[:], uint32(index)) case linux.SIOCGIFHWADDR: // Copy the hardware address out. // // Refer: https://linux.die.net/man/7/netdevice // SIOCGIFHWADDR, SIOCSIFHWADDR // // Get or set the hardware address of a device using // ifr_hwaddr. The hardware address is specified in a struct // sockaddr. sa_family contains the ARPHRD_* device type, // sa_data the L2 hardware address starting from byte 0. Setting // the hardware address is a privileged operation. usermem.ByteOrder.PutUint16(ifr.Data[:], iface.DeviceType) n := copy(ifr.Data[2:], iface.Addr) for i := 2 + n; i < len(ifr.Data); i++ { ifr.Data[i] = 0 // Clear padding. } case linux.SIOCGIFFLAGS: f, err := interfaceStatusFlags(stack, iface.Name) if err != nil { return err } // Drop the flags that don't fit in the size that we need to return. This // matches Linux behavior. usermem.ByteOrder.PutUint16(ifr.Data[:2], uint16(f)) case linux.SIOCGIFADDR: // Copy the IPv4 address out. for _, addr := range stack.InterfaceAddrs()[index] { // This ioctl is only compatible with AF_INET addresses. if addr.Family != linux.AF_INET { continue } copy(ifr.Data[4:8], addr.Addr) break } case linux.SIOCGIFMETRIC: // Gets the metric of the device. As per netdevice(7), this // always just sets ifr_metric to 0. usermem.ByteOrder.PutUint32(ifr.Data[:4], 0) case linux.SIOCGIFMTU: // Gets the MTU of the device. usermem.ByteOrder.PutUint32(ifr.Data[:4], iface.MTU) case linux.SIOCGIFMAP: // Gets the hardware parameters of the device. // TODO(gvisor.dev/issue/505): Implement. case linux.SIOCGIFTXQLEN: // Gets the transmit queue length of the device. // TODO(gvisor.dev/issue/505): Implement. case linux.SIOCGIFDSTADDR: // Gets the destination address of a point-to-point device. // TODO(gvisor.dev/issue/505): Implement. case linux.SIOCGIFBRDADDR: // Gets the broadcast address of a device. // TODO(gvisor.dev/issue/505): Implement. case linux.SIOCGIFNETMASK: // Gets the network mask of a device. for _, addr := range stack.InterfaceAddrs()[index] { // This ioctl is only compatible with AF_INET addresses. if addr.Family != linux.AF_INET { continue } // Populate ifr.ifr_netmask (type sockaddr). usermem.ByteOrder.PutUint16(ifr.Data[0:2], uint16(linux.AF_INET)) usermem.ByteOrder.PutUint16(ifr.Data[2:4], 0) var mask uint32 = 0xffffffff << (32 - addr.PrefixLen) // Netmask is expected to be returned as a big endian // value. binary.BigEndian.PutUint32(ifr.Data[4:8], mask) break } case linux.SIOCETHTOOL: // Stubbed out for now, Ideally we should implement the required // sub-commands for ETHTOOL // // See: // https://github.com/torvalds/linux/blob/aa0c9086b40c17a7ad94425b3b70dd1fdd7497bf/net/core/dev_ioctl.c return syserr.ErrEndpointOperation default: // Not a valid call. return syserr.ErrInvalidArgument } return nil } // ifconfIoctl populates a struct ifconf for the SIOCGIFCONF ioctl. func ifconfIoctl(ctx context.Context, t *kernel.Task, io usermem.IO, ifc *linux.IFConf) error { // If Ptr is NULL, return the necessary buffer size via Len. // Otherwise, write up to Len bytes starting at Ptr containing ifreq // structs. stack := inet.StackFromContext(ctx) if stack == nil { return syserr.ErrNoDevice.ToError() } if ifc.Ptr == 0 { ifc.Len = int32(len(stack.Interfaces())) * int32(linux.SizeOfIFReq) return nil } max := ifc.Len ifc.Len = 0 for key, ifaceAddrs := range stack.InterfaceAddrs() { iface := stack.Interfaces()[key] for _, ifaceAddr := range ifaceAddrs { // Don't write past the end of the buffer. if ifc.Len+int32(linux.SizeOfIFReq) > max { break } if ifaceAddr.Family != linux.AF_INET { continue } // Populate ifr.ifr_addr. ifr := linux.IFReq{} ifr.SetName(iface.Name) usermem.ByteOrder.PutUint16(ifr.Data[0:2], uint16(ifaceAddr.Family)) usermem.ByteOrder.PutUint16(ifr.Data[2:4], 0) copy(ifr.Data[4:8], ifaceAddr.Addr[:4]) // Copy the ifr to userspace. dst := uintptr(ifc.Ptr) + uintptr(ifc.Len) ifc.Len += int32(linux.SizeOfIFReq) if _, err := ifr.CopyOut(t, usermem.Addr(dst)); err != nil { return err } } } return nil } // interfaceStatusFlags returns status flags for an interface in the stack. // Flag values and meanings are described in greater detail in netdevice(7) in // the SIOCGIFFLAGS section. func interfaceStatusFlags(stack inet.Stack, name string) (uint32, *syserr.Error) { // We should only ever be passed a netstack.Stack. epstack, ok := stack.(*Stack) if !ok { return 0, errStackType } // Find the NIC corresponding to this interface. for _, info := range epstack.Stack.NICInfo() { if info.Name == name { return nicStateFlagsToLinux(info.Flags), nil } } return 0, syserr.ErrNoDevice } func nicStateFlagsToLinux(f stack.NICStateFlags) uint32 { var rv uint32 if f.Up { rv |= linux.IFF_UP | linux.IFF_LOWER_UP } if f.Running { rv |= linux.IFF_RUNNING } if f.Promiscuous { rv |= linux.IFF_PROMISC } if f.Loopback { rv |= linux.IFF_LOOPBACK } return rv } // State implements socket.Socket.State. State translates the internal state // returned by netstack to values defined by Linux. func (s *socketOpsCommon) State() uint32 { if s.family != linux.AF_INET && s.family != linux.AF_INET6 { // States not implemented for this socket's family. return 0 } switch { case s.skType == linux.SOCK_STREAM && s.protocol == 0 || s.protocol == syscall.IPPROTO_TCP: // 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 } case s.skType == linux.SOCK_DGRAM && s.protocol == 0 || s.protocol == syscall.IPPROTO_UDP: // UDP socket. switch udp.EndpointState(s.Endpoint.State()) { case udp.StateInitial, udp.StateBound, udp.StateClosed: return linux.TCP_CLOSE case udp.StateConnected: return linux.TCP_ESTABLISHED default: return 0 } case s.skType == linux.SOCK_DGRAM && s.protocol == syscall.IPPROTO_ICMP || s.protocol == syscall.IPPROTO_ICMPV6: // TODO(b/112063468): Export states for ICMP sockets. case s.skType == linux.SOCK_RAW: // TODO(b/112063468): Export states for raw sockets. default: // Unknown transport protocol, how did we make this socket? log.Warningf("Unknown transport protocol for an existing socket: family=%v, type=%v, protocol=%v, internal type %v", s.family, s.skType, s.protocol, reflect.TypeOf(s.Endpoint).Elem()) return 0 } return 0 } // Type implements socket.Socket.Type. func (s *socketOpsCommon) Type() (family int, skType linux.SockType, protocol int) { return s.family, s.skType, s.protocol } // LINT.ThenChange(./netstack_vfs2.go)