vendor: bump github.com/mdlayher/wifi and dependencies (#1045)

Signed-off-by: Matt Layher <mdlayher@gmail.com>

vendor/github.com/mdlayher/genetlink/conn.go

@@ -67,6 +67,16 @@ func (c *Conn) SetBPF(filter []bpf.RawInstruction) error {
 	return c.c.SetBPF(filter)
 }
 
+// RemoveBPF removes a BPF filter from a Conn.
+func (c *Conn) RemoveBPF() error {
+	return c.c.RemoveBPF()
+}
+
+// SetOption enables or disables a netlink socket option for the Conn.
+func (c *Conn) SetOption(option netlink.ConnOption, enable bool) error {
+	return c.c.SetOption(option, enable)
+}
+
 // Send sends a single Message to netlink, wrapping it in a netlink.Message
 // using the specified generic netlink family and flags.  On success, Send
 // returns a copy of the netlink.Message with all parameters populated, for

vendor/github.com/mdlayher/genetlink/family_linux.go

@@ -16,10 +16,6 @@ var (
 	// errInvalidFamilyVersion is returned when a family's version is greater
 	// than an 8-bit integer.
 	errInvalidFamilyVersion = errors.New("invalid family version attribute")
-
-	// errInvalidMulticastGroupArray is returned when a multicast group array
-	// of attributes is malformed.
-	errInvalidMulticastGroupArray = errors.New("invalid multicast group attribute array")
 )
 
 // getFamily retrieves a generic netlink family with the specified name.
@@ -85,13 +81,8 @@ func (c *Conn) listFamilies() ([]Family, error) {
 func buildFamilies(msgs []Message) ([]Family, error) {
 	families := make([]Family, 0, len(msgs))
 	for _, m := range msgs {
-		attrs, err := netlink.UnmarshalAttributes(m.Data)
-		if err != nil {
-			return nil, err
-		}
-
 		var f Family
-		if err := (&f).parseAttributes(attrs); err != nil {
+		if err := (&f).parseAttributes(m.Data); err != nil {
 			return nil, err
 		}
 
@@ -101,66 +92,79 @@ func buildFamilies(msgs []Message) ([]Family, error) {
 	return families, nil
 }
 
-// parseAttributes parses netlink attributes into a Family's fields.
-func (f *Family) parseAttributes(attrs []netlink.Attribute) error {
-	for _, a := range attrs {
-		switch a.Type {
+// parseAttributes decodes netlink attributes into a Family's fields.
+func (f *Family) parseAttributes(b []byte) error {
+	ad, err := netlink.NewAttributeDecoder(b)
+	if err != nil {
+		return err
+	}
+
+	for ad.Next() {
+		switch ad.Type() {
 		case unix.CTRL_ATTR_FAMILY_ID:
-			f.ID = nlenc.Uint16(a.Data)
+			f.ID = ad.Uint16()
 		case unix.CTRL_ATTR_FAMILY_NAME:
-			f.Name = nlenc.String(a.Data)
+			f.Name = ad.String()
 		case unix.CTRL_ATTR_VERSION:
-			v := nlenc.Uint32(a.Data)
+			v := ad.Uint32()
 			if v > math.MaxUint8 {
 				return errInvalidFamilyVersion
 			}
 
 			f.Version = uint8(v)
 		case unix.CTRL_ATTR_MCAST_GROUPS:
-			groups, err := parseMulticastGroups(a.Data)
-			if err != nil {
-				return err
-			}
+			ad.Do(func(b []byte) error {
+				groups, err := parseMulticastGroups(b)
+				if err != nil {
+					return err
+				}
 
-			f.Groups = groups
+				f.Groups = groups
+				return nil
+			})
 		}
 	}
 
-	return nil
+	return ad.Err()
 }
 
 // parseMulticastGroups parses an array of multicast group nested attributes
 // into a slice of MulticastGroups.
 func parseMulticastGroups(b []byte) ([]MulticastGroup, error) {
-	attrs, err := netlink.UnmarshalAttributes(b)
+	ad, err := netlink.NewAttributeDecoder(b)
 	if err != nil {
 		return nil, err
 	}
 
-	groups := make([]MulticastGroup, 0, len(attrs))
-	for i, a := range attrs {
-		// The type attribute is essentially an array index here; it starts
-		// at 1 and should increment for each new array element
-		if int(a.Type) != i+1 {
-			return nil, errInvalidMulticastGroupArray
-		}
-
-		nattrs, err := netlink.UnmarshalAttributes(a.Data)
-		if err != nil {
-			return nil, err
-		}
-
-		var g MulticastGroup
-		for _, na := range nattrs {
-			switch na.Type {
-			case unix.CTRL_ATTR_MCAST_GRP_NAME:
-				g.Name = nlenc.String(na.Data)
-			case unix.CTRL_ATTR_MCAST_GRP_ID:
-				g.ID = nlenc.Uint32(na.Data)
+	var groups []MulticastGroup
+	for ad.Next() {
+		ad.Do(func(b []byte) error {
+			adi, err := netlink.NewAttributeDecoder(b)
+			if err != nil {
+				return err
 			}
-		}
 
-		groups = append(groups, g)
+			var g MulticastGroup
+			for adi.Next() {
+				switch adi.Type() {
+				case unix.CTRL_ATTR_MCAST_GRP_NAME:
+					g.Name = adi.String()
+				case unix.CTRL_ATTR_MCAST_GRP_ID:
+					g.ID = adi.Uint32()
+				}
+			}
+
+			if err := ad.Err(); err != nil {
+				return err
+			}
+
+			groups = append(groups, g)
+			return nil
+		})
+	}
+
+	if err := ad.Err(); err != nil {
+		return nil, err
 	}
 
 	return groups, nil

vendor/github.com/mdlayher/netlink/attribute.go

@@ -1,7 +1,9 @@
 package netlink
 
 import (
+	"encoding/binary"
 	"errors"
+	"fmt"
 
 	"github.com/mdlayher/netlink/nlenc"
 )
@@ -9,9 +11,6 @@ import (
 var (
 	// errInvalidAttribute specifies if an Attribute's length is incorrect.
 	errInvalidAttribute = errors.New("invalid attribute; length too short or too large")
-	// errInvalidAttributeFlags specifies if an Attribute's flag configuration is invalid.
-	// From a comment in Linux/include/uapi/linux/netlink.h, Nested and NetByteOrder are mutually exclusive.
-	errInvalidAttributeFlags = errors.New("invalid attribute; type cannot have both nested and net byte order flags")
 )
 
 // An Attribute is a netlink attribute.  Attributes are packed and unpacked
@@ -25,48 +24,18 @@ type Attribute struct {
 
 	// An arbitrary payload which is specified by Type.
 	Data []byte
-
-	// Whether the attribute's data contains nested attributes.  Note that not
-	// all netlink families set this value.  The programmer should consult
-	// documentation and inspect an attribute's data to determine if nested
-	// attributes are present.
-	Nested bool
-
-	// Whether the attribute's data is in network (true) or native (false) byte order.
-	NetByteOrder bool
 }
 
-// #define NLA_F_NESTED
-const nlaNested uint16 = 0x8000
-
-// #define NLA_F_NET_BYTE_ORDER
-const nlaNetByteOrder uint16 = 0x4000
-
-// Masks all bits except for Nested and NetByteOrder.
-const nlaTypeMask = ^(nlaNested | nlaNetByteOrder)
-
 // MarshalBinary marshals an Attribute into a byte slice.
 func (a Attribute) MarshalBinary() ([]byte, error) {
 	if int(a.Length) < nlaHeaderLen {
 		return nil, errInvalidAttribute
 	}
 
-	if a.NetByteOrder && a.Nested {
-		return nil, errInvalidAttributeFlags
-	}
-
 	b := make([]byte, nlaAlign(int(a.Length)))
 
 	nlenc.PutUint16(b[0:2], a.Length)
-
-	switch {
-	case a.Nested:
-		nlenc.PutUint16(b[2:4], a.Type|nlaNested)
-	case a.NetByteOrder:
-		nlenc.PutUint16(b[2:4], a.Type|nlaNetByteOrder)
-	default:
-		nlenc.PutUint16(b[2:4], a.Type)
-	}
+	nlenc.PutUint16(b[2:4], a.Type)
 
 	copy(b[nlaHeaderLen:], a.Data)
 
@@ -80,22 +49,12 @@ func (a *Attribute) UnmarshalBinary(b []byte) error {
 	}
 
 	a.Length = nlenc.Uint16(b[0:2])
-
-	// Only hold the rightmost 14 bits in Type
-	a.Type = nlenc.Uint16(b[2:4]) & nlaTypeMask
-
-	// Boolean flags extracted from the two leftmost bits of Type
-	a.Nested = (nlenc.Uint16(b[2:4]) & nlaNested) > 0
-	a.NetByteOrder = (nlenc.Uint16(b[2:4]) & nlaNetByteOrder) > 0
+	a.Type = nlenc.Uint16(b[2:4])
 
 	if nlaAlign(int(a.Length)) > len(b) {
 		return errInvalidAttribute
 	}
 
-	if a.NetByteOrder && a.Nested {
-		return errInvalidAttributeFlags
-	}
-
 	switch {
 	// No length, no data
 	case a.Length == 0:
@@ -139,6 +98,9 @@ func MarshalAttributes(attrs []Attribute) ([]byte, error) {
 }
 
 // UnmarshalAttributes unpacks a slice of Attributes from a single byte slice.
+//
+// It is recommend to use the AttributeDecoder type where possible instead of calling
+// UnmarshalAttributes and using package nlenc functions directly.
 func UnmarshalAttributes(b []byte) ([]Attribute, error) {
 	var attrs []Attribute
 	var i int
@@ -164,3 +126,173 @@ func UnmarshalAttributes(b []byte) ([]Attribute, error) {
 
 	return attrs, nil
 }
+
+// An AttributeDecoder provides a safe, iterator-like, API around attribute
+// decoding.
+//
+// It is recommend to use an AttributeDecoder where possible instead of calling
+// UnmarshalAttributes and using package nlenc functions directly.
+//
+// The Err method must be called after the Next method returns false to determine
+// if any errors occurred during iteration.
+type AttributeDecoder struct {
+	// ByteOrder defines a specific byte order to use when processing integer
+	// attributes.  ByteOrder should be set immediately after creating the
+	// AttributeDecoder: before any attributes are parsed.
+	//
+	// If not set, the native byte order will be used.
+	ByteOrder binary.ByteOrder
+
+	// The attributes being worked on, and the iterator index into the slice of
+	// attributes.
+	attrs []Attribute
+	i     int
+
+	// Any error encountered while decoding attributes.
+	err error
+}
+
+// NewAttributeDecoder creates an AttributeDecoder that unpacks Attributes
+// from b and prepares the decoder for iteration.
+func NewAttributeDecoder(b []byte) (*AttributeDecoder, error) {
+	attrs, err := UnmarshalAttributes(b)
+	if err != nil {
+		return nil, err
+	}
+
+	return &AttributeDecoder{
+		// By default, use native byte order.
+		ByteOrder: nlenc.NativeEndian(),
+
+		attrs: attrs,
+	}, nil
+}
+
+// Next advances the decoder to the next netlink attribute.  It returns false
+// when no more attributes are present, or an error was encountered.
+func (ad *AttributeDecoder) Next() bool {
+	if ad.err != nil {
+		// Hit an error, stop iteration.
+		return false
+	}
+
+	ad.i++
+
+	if len(ad.attrs) < ad.i {
+		// No more attributes, stop iteration.
+		return false
+	}
+
+	return true
+}
+
+// Type returns the Attribute.Type field of the current netlink attribute
+// pointed to by the decoder.
+func (ad *AttributeDecoder) Type() uint16 {
+	return ad.attr().Type
+}
+
+// attr returns the current Attribute pointed to by the decoder.
+func (ad *AttributeDecoder) attr() Attribute {
+	return ad.attrs[ad.i-1]
+}
+
+// data returns the Data field of the current Attribute pointed to by the decoder.
+func (ad *AttributeDecoder) data() []byte {
+	return ad.attr().Data
+}
+
+// Err returns the first error encountered by the decoder.
+func (ad *AttributeDecoder) Err() error {
+	return ad.err
+}
+
+// String returns the string representation of the current Attribute's data.
+func (ad *AttributeDecoder) String() string {
+	if ad.err != nil {
+		return ""
+	}
+
+	return nlenc.String(ad.data())
+}
+
+// Uint8 returns the uint8 representation of the current Attribute's data.
+func (ad *AttributeDecoder) Uint8() uint8 {
+	if ad.err != nil {
+		return 0
+	}
+
+	b := ad.data()
+	if len(b) != 1 {
+		ad.err = fmt.Errorf("netlink: attribute %d is not a uint8; length: %d", ad.Type(), len(b))
+		return 0
+	}
+
+	return uint8(b[0])
+}
+
+// Uint16 returns the uint16 representation of the current Attribute's data.
+func (ad *AttributeDecoder) Uint16() uint16 {
+	if ad.err != nil {
+		return 0
+	}
+
+	b := ad.data()
+	if len(b) != 2 {
+		ad.err = fmt.Errorf("netlink: attribute %d is not a uint16; length: %d", ad.Type(), len(b))
+		return 0
+	}
+
+	return ad.ByteOrder.Uint16(b)
+}
+
+// Uint32 returns the uint32 representation of the current Attribute's data.
+func (ad *AttributeDecoder) Uint32() uint32 {
+	if ad.err != nil {
+		return 0
+	}
+
+	b := ad.data()
+	if len(b) != 4 {
+		ad.err = fmt.Errorf("netlink: attribute %d is not a uint32; length: %d", ad.Type(), len(b))
+		return 0
+	}
+
+	return ad.ByteOrder.Uint32(b)
+}
+
+// Uint64 returns the uint64 representation of the current Attribute's data.
+func (ad *AttributeDecoder) Uint64() uint64 {
+	if ad.err != nil {
+		return 0
+	}
+
+	b := ad.data()
+	if len(b) != 8 {
+		ad.err = fmt.Errorf("netlink: attribute %d is not a uint64; length: %d", ad.Type(), len(b))
+		return 0
+	}
+
+	return ad.ByteOrder.Uint64(b)
+}
+
+// Do is a general purpose function which allows access to the current data
+// pointed to by the AttributeDecoder.
+//
+// Do can be used to allow parsing arbitrary data within the context of the
+// decoder.  Do is most useful when dealing with nested attributes, attribute
+// arrays, or decoding arbitrary types (such as C structures) which don't fit
+// cleanly into a typical unsigned integer value.
+//
+// The function fn should not retain any reference to the data b outside of the
+// scope of the function.
+func (ad *AttributeDecoder) Do(fn func(b []byte) error) {
+	if ad.err != nil {
+		return
+	}
+
+	b := ad.data()
+	if err := fn(b); err != nil {
+		ad.err = err
+	}
+}

vendor/github.com/mdlayher/netlink/conn.go

@@ -6,6 +6,7 @@ import (
 	"math/rand"
 	"os"
 	"sync/atomic"
+	"time"
 
 	"golang.org/x/net/bpf"
 )
@@ -23,6 +24,7 @@ var (
 	errReadWriteCloserNotSupported = errors.New("raw read/write/closer not supported")
 	errMulticastGroupsNotSupported = errors.New("multicast groups not supported")
 	errBPFFiltersNotSupported      = errors.New("BPF filters not supported")
+	errOptionsNotSupported         = errors.New("options not supported")
 )
 
 // A Conn is a connection to netlink.  A Conn can be used to send and
@@ -42,6 +44,9 @@ type Conn struct {
 
 	// pid is the PID assigned by netlink.
 	pid uint32
+
+	// d provides debugging capabilities for a Conn if not nil.
+	d *debugger
 }
 
 // A Socket is an operating-system specific implementation of netlink
@@ -49,6 +54,7 @@ type Conn struct {
 type Socket interface {
 	Close() error
 	Send(m Message) error
+	SendMessages(m []Message) error
 	Receive() ([]Message, error)
 }
 
@@ -71,15 +77,33 @@ func Dial(family int, config *Config) (*Conn, error) {
 // NewConn is primarily useful for tests. Most applications should use
 // Dial instead.
 func NewConn(c Socket, pid uint32) *Conn {
-	seq := rand.Uint32()
+	// Seed the sequence number using a random number generator.
+	r := rand.New(rand.NewSource(time.Now().UnixNano()))
+	seq := r.Uint32()
+
+	// Configure a debugger if arguments are set.
+	var d *debugger
+	if len(debugArgs) > 0 {
+		d = newDebugger(debugArgs)
+	}
 
 	return &Conn{
 		sock: c,
 		seq:  &seq,
 		pid:  pid,
+		d:    d,
 	}
 }
 
+// debug executes fn with the debugger if the debugger is not nil.
+func (c *Conn) debug(fn func(d *debugger)) {
+	if c.d == nil {
+		return
+	}
+
+	fn(c.d)
+}
+
 // Close closes the connection.
 func (c *Conn) Close() error {
 	return c.sock.Close()
@@ -109,6 +133,51 @@ func (c *Conn) Execute(m Message) ([]Message, error) {
 	return replies, nil
 }
 
+func (c *Conn) fixMsg(m *Message, ml int) {
+	if m.Header.Length == 0 {
+		m.Header.Length = uint32(nlmsgAlign(ml))
+	}
+
+	if m.Header.Sequence == 0 {
+		m.Header.Sequence = c.nextSequence()
+	}
+
+	if m.Header.PID == 0 {
+		m.Header.PID = c.pid
+	}
+}
+
+// SendMessages sends multiple Messages to netlink. The handling of
+// m.Header.Length, Sequence and PID is the same as when calling Send.
+func (c *Conn) SendMessages(messages []Message) ([]Message, error) {
+	for idx, m := range messages {
+		ml := nlmsgLength(len(m.Data))
+
+		// TODO(mdlayher): fine-tune this limit.
+		if ml > (1024 * 32) {
+			return nil, errors.New("netlink message data too large")
+		}
+
+		c.fixMsg(&messages[idx], ml)
+	}
+
+	c.debug(func(d *debugger) {
+		for _, m := range messages {
+			d.debugf(1, "send msgs: %+v", m)
+		}
+	})
+
+	if err := c.sock.SendMessages(messages); err != nil {
+		c.debug(func(d *debugger) {
+			d.debugf(1, "send msgs: err: %v", err)
+		})
+
+		return nil, err
+	}
+
+	return messages, nil
+}
+
 // Send sends a single Message to netlink.  In most cases, m.Header's Length,
 // Sequence, and PID fields should be set to 0, so they can be populated
 // automatically before the Message is sent.  On success, Send returns a copy
@@ -130,19 +199,17 @@ func (c *Conn) Send(m Message) (Message, error) {
 		return Message{}, errors.New("netlink message data too large")
 	}
 
-	if m.Header.Length == 0 {
-		m.Header.Length = uint32(nlmsgAlign(ml))
-	}
+	c.fixMsg(&m, ml)
 
-	if m.Header.Sequence == 0 {
-		m.Header.Sequence = c.nextSequence()
-	}
-
-	if m.Header.PID == 0 {
-		m.Header.PID = c.pid
-	}
+	c.debug(func(d *debugger) {
+		d.debugf(1, "send: %+v", m)
+	})
 
 	if err := c.sock.Send(m); err != nil {
+		c.debug(func(d *debugger) {
+			d.debugf(1, "send: err: %v", err)
+		})
+
 		return Message{}, err
 	}
 
@@ -157,9 +224,19 @@ func (c *Conn) Send(m Message) (Message, error) {
 func (c *Conn) Receive() ([]Message, error) {
 	msgs, err := c.receive()
 	if err != nil {
+		c.debug(func(d *debugger) {
+			d.debugf(1, "recv: err: %v", err)
+		})
+
 		return nil, err
 	}
 
+	c.debug(func(d *debugger) {
+		for _, m := range msgs {
+			d.debugf(1, "recv: %+v", m)
+		}
+	})
+
 	// When using nltest, it's possible for zero messages to be returned by receive.
 	if len(msgs) == 0 {
 		return msgs, nil
@@ -177,37 +254,40 @@ func (c *Conn) Receive() ([]Message, error) {
 // receive is the internal implementation of Conn.Receive, which can be called
 // recursively to handle multi-part messages.
 func (c *Conn) receive() ([]Message, error) {
-	msgs, err := c.sock.Receive()
-	if err != nil {
-		return nil, err
-	}
-
-	// If this message is multi-part, we will need to perform an recursive call
-	// to continue draining the socket
-	var multi bool
-
-	for _, m := range msgs {
-		// Is this a multi-part message and is it not done yet?
-		if m.Header.Flags&HeaderFlagsMulti != 0 && m.Header.Type != HeaderTypeDone {
-			multi = true
-		}
-
-		if err := checkMessage(m); err != nil {
+	var res []Message
+	for {
+		msgs, err := c.sock.Receive()
+		if err != nil {
 			return nil, err
 		}
-	}
 
-	if !multi {
-		return msgs, nil
-	}
+		// If this message is multi-part, we will need to perform an recursive call
+		// to continue draining the socket
+		var multi bool
 
-	// More messages waiting
-	mmsgs, err := c.receive()
-	if err != nil {
-		return nil, err
-	}
+		for _, m := range msgs {
+			if err := checkMessage(m); err != nil {
+				return nil, err
+			}
 
-	return append(msgs, mmsgs...), nil
+			// Does this message indicate a multi-part message?
+			if m.Header.Flags&HeaderFlagsMulti == 0 {
+				// No, check the next messages.
+				continue
+			}
+
+			// Does this message indicate the last message in a series of
+			// multi-part messages from a single read?
+			multi = m.Header.Type != HeaderTypeDone
+		}
+
+		res = append(res, msgs...)
+
+		if !multi {
+			// No more messages coming.
+			return res, nil
+		}
+	}
 }
 
 // An fder is a Socket that supports retrieving its raw file descriptor.
@@ -283,10 +363,11 @@ func (c *Conn) LeaveGroup(group uint32) error {
 	return gc.LeaveGroup(group)
 }
 
-// A bpfSetter is a Socket that supports setting BPF filters.
+// A bpfSetter is a Socket that supports setting and removing BPF filters.
 type bpfSetter interface {
 	Socket
 	bpf.Setter
+	RemoveBPF() error
 }
 
 // SetBPF attaches an assembled BPF program to a Conn.
@@ -299,6 +380,45 @@ func (c *Conn) SetBPF(filter []bpf.RawInstruction) error {
 	return bc.SetBPF(filter)
 }
 
+// RemoveBPF removes a BPF filter from a Conn.
+func (c *Conn) RemoveBPF() error {
+	s, ok := c.sock.(bpfSetter)
+	if !ok {
+		return errBPFFiltersNotSupported
+	}
+
+	return s.RemoveBPF()
+}
+
+// A ConnOption is a boolean option that may be set for a Conn.
+type ConnOption int
+
+// Possible ConnOption values.  These constants are equivalent to the Linux
+// setsockopt boolean options for netlink sockets.
+const (
+	PacketInfo ConnOption = iota
+	BroadcastError
+	NoENOBUFS
+	ListenAllNSID
+	CapAcknowledge
+)
+
+// An optionSetter is a Socket that supports setting netlink options.
+type optionSetter interface {
+	Socket
+	SetOption(option ConnOption, enable bool) error
+}
+
+// SetOption enables or disables a netlink socket option for the Conn.
+func (c *Conn) SetOption(option ConnOption, enable bool) error {
+	fc, ok := c.sock.(optionSetter)
+	if !ok {
+		return errOptionsNotSupported
+	}
+
+	return fc.SetOption(option, enable)
+}
+
 // nextSequence atomically increments Conn's sequence number and returns
 // the incremented value.
 func (c *Conn) nextSequence() uint32 {

vendor/github.com/mdlayher/netlink/conn_linux.go

@@ -94,6 +94,25 @@ func bind(s socket, config *Config) (*conn, uint32, error) {
 	}, pid, nil
 }
 
+// SendMessages serializes multiple Messages and sends them to netlink.
+func (c *conn) SendMessages(messages []Message) error {
+	var buf []byte
+	for _, m := range messages {
+		b, err := m.MarshalBinary()
+		if err != nil {
+			return err
+		}
+
+		buf = append(buf, b...)
+	}
+
+	addr := &unix.SockaddrNetlink{
+		Family: unix.AF_NETLINK,
+	}
+
+	return c.s.Sendmsg(buf, nil, addr, 0)
+}
+
 // Send sends a single Message to netlink.
 func (c *conn) Send(m Message) error {
 	b, err := m.MarshalBinary()
@@ -112,7 +131,10 @@ func (c *conn) Send(m Message) error {
 func (c *conn) Receive() ([]Message, error) {
 	b := make([]byte, os.Getpagesize())
 	for {
-		// Peek at the buffer to see how many bytes are available
+		// Peek at the buffer to see how many bytes are available.
+		//
+		// TODO(mdlayher): deal with OOB message data if available, such as
+		// when PacketInfo ConnOption is true.
 		n, _, _, _, err := c.s.Recvmsg(b, nil, unix.MSG_PEEK)
 		if err != nil {
 			return nil, err
@@ -204,6 +226,58 @@ func (c *conn) SetBPF(filter []bpf.RawInstruction) error {
 	)
 }
 
+// RemoveBPF removes a BPF filter from a conn.
+func (c *conn) RemoveBPF() error {
+	// dummy is ignored as argument to SO_DETACH_FILTER
+	// but SetSockopt requires it as an argument
+	var dummy uint32
+	return c.s.SetSockopt(
+		unix.SOL_SOCKET,
+		unix.SO_DETACH_FILTER,
+		unsafe.Pointer(&dummy),
+		uint32(unsafe.Sizeof(dummy)),
+	)
+}
+
+// SetOption enables or disables a netlink socket option for the Conn.
+func (c *conn) SetOption(option ConnOption, enable bool) error {
+	o, ok := linuxOption(option)
+	if !ok {
+		// Return the typical Linux error for an unknown ConnOption.
+		return unix.ENOPROTOOPT
+	}
+
+	var v uint32
+	if enable {
+		v = 1
+	}
+
+	return c.s.SetSockopt(
+		unix.SOL_NETLINK,
+		o,
+		unsafe.Pointer(&v),
+		uint32(unsafe.Sizeof(v)),
+	)
+}
+
+// linuxOption converts a ConnOption to its Linux value.
+func linuxOption(o ConnOption) (int, bool) {
+	switch o {
+	case PacketInfo:
+		return unix.NETLINK_PKTINFO, true
+	case BroadcastError:
+		return unix.NETLINK_BROADCAST_ERROR, true
+	case NoENOBUFS:
+		return unix.NETLINK_NO_ENOBUFS, true
+	case ListenAllNSID:
+		return unix.NETLINK_LISTEN_ALL_NSID, true
+	case CapAcknowledge:
+		return unix.NETLINK_CAP_ACK, true
+	default:
+		return 0, false
+	}
+}
+
 // sysToHeader converts a syscall.NlMsghdr to a Header.
 func sysToHeader(r syscall.NlMsghdr) Header {
 	// NB: the memory layout of Header and syscall.NlMsgHdr must be
@@ -247,10 +321,20 @@ func newSysSocket(lockThread bool) *sysSocket {
 		// But since this is very experimental, we'll leave it as a configurable at
 		// this point.
 		if lockThread {
-			// Never unlock the OS thread, so that the thread will terminate when
-			// the goroutine exits starting in Go 1.10:
+			// The intent is to never unlock the OS thread, so that the thread
+			// will terminate when the goroutine exits starting in Go 1.10:
 			// https://go-review.googlesource.com/c/go/+/46038.
+			//
+			// However, due to recent instability and a potential bad interaction
+			// with the Go runtime for threads which are not unlocked, we have
+			// elected to temporarily unlock the thread:
+			// https://github.com/golang/go/issues/25128#issuecomment-410764489.
+			//
+			// If we ever allow a Conn to set its own network namespace, we must
+			// either ensure that the namespace is restored on exit here or that
+			// the thread is properly terminated at some point in the future.
 			runtime.LockOSThread()
+			defer runtime.UnlockOSThread()
 		}
 
 		defer wg.Done()

vendor/github.com/mdlayher/netlink/conn_others.go

@@ -5,14 +5,12 @@ package netlink
 import (
 	"fmt"
 	"runtime"
-
-	"golang.org/x/net/bpf"
 )
 
 var (
 	// errUnimplemented is returned by all functions on platforms that
 	// cannot make use of netlink sockets.
-	errUnimplemented = fmt.Errorf("netlink sockets not implemented on %s/%s",
+	errUnimplemented = fmt.Errorf("netlink: not implemented on %s/%s",
 		runtime.GOOS, runtime.GOARCH)
 )
 
@@ -21,42 +19,13 @@ var _ Socket = &conn{}
 // A conn is the no-op implementation of a netlink sockets connection.
 type conn struct{}
 
-// dial is the entry point for Dial.  dial always returns an error.
-func dial(family int, config *Config) (*conn, uint32, error) {
-	return nil, 0, errUnimplemented
-}
+// All cross-platform functions and Socket methods are unimplemented outside
+// of Linux.
 
-// Send always returns an error.
-func (c *conn) Send(m Message) error {
-	return errUnimplemented
-}
+func dial(_ int, _ *Config) (*conn, uint32, error) { return nil, 0, errUnimplemented }
+func newError(_ int) error                         { return errUnimplemented }
 
-// Receive always returns an error.
-func (c *conn) Receive() ([]Message, error) {
-	return nil, errUnimplemented
-}
-
-// Close always returns an error.
-func (c *conn) Close() error {
-	return errUnimplemented
-}
-
-// JoinGroup always returns an error.
-func (c *conn) JoinGroup(group uint32) error {
-	return errUnimplemented
-}
-
-// LeaveGroup always returns an error.
-func (c *conn) LeaveGroup(group uint32) error {
-	return errUnimplemented
-}
-
-// SetBPF always returns an error.
-func (c *conn) SetBPF(filter []bpf.RawInstruction) error {
-	return errUnimplemented
-}
-
-// newError always returns an error.
-func newError(errno int) error {
-	return errUnimplemented
-}
+func (c *conn) Send(_ Message) error           { return errUnimplemented }
+func (c *conn) SendMessages(_ []Message) error { return errUnimplemented }
+func (c *conn) Receive() ([]Message, error)    { return nil, errUnimplemented }
+func (c *conn) Close() error                   { return errUnimplemented }

vendor/github.com/mdlayher/netlink/debug.go

@@ -0,0 +1,71 @@
+package netlink
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+)
+
+var (
+	// Arguments used to create a debugger.
+	debugArgs []string
+)
+
+func init() {
+	// Is netlink debugging enabled?
+	s := os.Getenv("NLDEBUG")
+	if s == "" {
+		return
+	}
+
+	debugArgs = strings.Split(s, ",")
+}
+
+// A debugger is used to provide debugging information about a netlink connection.
+type debugger struct {
+	Log   *log.Logger
+	Level int
+}
+
+// newDebugger creates a debugger by parsing key=value arguments.
+func newDebugger(args []string) *debugger {
+	d := &debugger{
+		Log:   log.New(os.Stderr, "nl: ", 0),
+		Level: 1,
+	}
+
+	for _, a := range args {
+		kv := strings.Split(a, "=")
+		if len(kv) != 2 {
+			// Ignore malformed pairs and assume callers wants defaults.
+			continue
+		}
+
+		switch kv[0] {
+		// Select the log level for the debugger.
+		case "level":
+			level, err := strconv.Atoi(kv[1])
+			if err != nil {
+				panicf("netlink: invalid NLDEBUG level: %q", a)
+			}
+
+			d.Level = level
+		}
+	}
+
+	return d
+}
+
+// debugf prints debugging information at the specified level, if d.Level is
+// high enough to print the message.
+func (d *debugger) debugf(level int, format string, v ...interface{}) {
+	if d.Level >= level {
+		d.Log.Printf(format, v...)
+	}
+}
+
+func panicf(format string, a ...interface{}) {
+	panic(fmt.Sprintf(format, a...))
+}

vendor/github.com/mdlayher/netlink/doc.go

@@ -1,2 +1,22 @@
 // Package netlink provides low-level access to Linux netlink sockets.
+//
+//
+// Debugging
+//
+// This package supports rudimentary netlink connection debugging support.
+// To enable this, run your binary with the NLDEBUG environment variable set.
+// Debugging information will be output to stderr with a prefix of "nl:".
+//
+// To use the debugging defaults, use:
+//
+//   $ NLDEBUG=1 ./nlctl
+//
+// To configure individual aspects of the debugger, pass key/value options such
+// as:
+//
+//   $ NLDEBUG=level=1 ./nlctl
+//
+// Available key/value debugger options include:
+//
+//   level=N: specify the debugging level (only "1" is currently supported)
 package netlink

vendor/github.com/mdlayher/netlink/nlenc/endian.go

@@ -0,0 +1,16 @@
+package nlenc
+
+import (
+	"encoding/binary"
+)
+
+// NativeEndian returns the native byte order of this system.
+func NativeEndian() binary.ByteOrder {
+	// Determine endianness by storing a uint16 in a byte slice.
+	b := Uint16Bytes(1)
+	if b[0] == 1 {
+		return binary.LittleEndian
+	}
+
+	return binary.BigEndian
+}

vendor/vendor.json

@@ -85,28 +85,28 @@
 			"versionExact": "v1.0.0"
 		},
 		{
-			"checksumSHA1": "VZIJG8dML/XqZbL9bpeDNgkazcg=",
+			"checksumSHA1": "zLH8BV9kYzpqGB5PS4VDjADFvVM=",
 			"path": "github.com/mdlayher/genetlink",
-			"revision": "76fecce4c787fb8eaa21a8755f722d67c53038e1",
-			"revisionTime": "2017-09-01T18:19:24Z"
+			"revision": "ca85b5a307448462b0aa7a07c67c0846bc12568f",
+			"revisionTime": "2018-07-28T17:03:40Z"
 		},
 		{
-			"checksumSHA1": "S6NatJYh1aOFzSIs6Agp2R0ydtM=",
+			"checksumSHA1": "ybkJbYD6wyjdoPp/KncnDpCyYiU=",
 			"path": "github.com/mdlayher/netlink",
-			"revision": "756e798fb38fac19fb2234d3acc32e902bc1af44",
-			"revisionTime": "2017-12-14T18:12:53Z"
+			"revision": "80a6f93efd374ddee4e0ea862ca0085ef42eed65",
+			"revisionTime": "2018-08-10T15:28:04Z"
 		},
 		{
-			"checksumSHA1": "9nig0WuuiTICStI/8S+pIGqYksc=",
+			"checksumSHA1": "P7eEo2V7/kQEkt2ihW+26S39eEw=",
 			"path": "github.com/mdlayher/netlink/nlenc",
-			"revision": "756e798fb38fac19fb2234d3acc32e902bc1af44",
-			"revisionTime": "2017-12-14T18:12:53Z"
+			"revision": "80a6f93efd374ddee4e0ea862ca0085ef42eed65",
+			"revisionTime": "2018-08-10T15:28:04Z"
 		},
 		{
 			"checksumSHA1": "Y7cjrOeOvA/ic+B8WCp2JyLEuvs=",
 			"path": "github.com/mdlayher/wifi",
-			"revision": "9a2549315201616119128afe421d1601ef3506f9",
-			"revisionTime": "2018-06-15T12:49:15Z"
+			"revision": "efdf3f4195d9fc8b73013b3706fe626b7fb807d8",
+			"revisionTime": "2018-07-27T16:38:19Z"
 		},
 		{
 			"checksumSHA1": "VzutdH69PUqRqhrDVv6F91ebQd4=",