Update vendoring (#722)

* Update vendor github.com/beevik/ntp@v0.2.0

* Update vendor github.com/mdlayher/netlink/...

* Update vendor github.com/mdlayher/wifi/...

Adds vendor github.com/mdlayher/genetlink

* Update vendor github.com/prometheus/common/...

* Update vendor github.com/prometheus/procfs/...

* Update vendor golang.org/x/sys/unix

* Update vendor golang.org/x/sys/windows

vendor/github.com/beevik/ntp/LICENSE

-Copyright 2015 Brett Vickers. All rights reserved.
+Copyright 2015-2017 Brett Vickers. All rights reserved.
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions

vendor/github.com/beevik/ntp/README.md

-[![Build Status](https://travis-ci.org/beevik/ntp.svg?branch=master)](https://travis-ci.org/beevik/ntp)
-[![GoDoc](https://godoc.org/github.com/beevik/ntp?status.svg)](https://godoc.org/github.com/beevik/ntp)
-
-ntp
-===
-
-The ntp package is an implementation of a Simple NTP (SNTP) client based on
-[RFC5905](https://tools.ietf.org/html/rfc5905). It allows you to connect to
-a remote NTP server and request the current time.
-
-If all you care about is the current time according to a known remote NTP
-server, simply use the `Time` function:
-```go
-time, err := ntp.Time("0.beevik-ntp.pool.ntp.org")
-```
-
-If you want the time as well as additional metadata about the time, use the
-`Query` function instead:
-```go
-response, err := ntp.Query("0.beevik-ntp.pool.ntp.org")
-```
-
-To use the NTP pool in your application, please request your own
-[vendor zone](http://www.pool.ntp.org/en/vendors.html).  Avoid using 
-the `[number].pool.ntp.org` zone names in your applications.
+[![Build Status](https://travis-ci.org/beevik/ntp.svg?branch=master)](https://travis-ci.org/beevik/ntp)
+[![GoDoc](https://godoc.org/github.com/beevik/ntp?status.svg)](https://godoc.org/github.com/beevik/ntp)
+
+ntp
+===
+
+The ntp package is an implementation of a Simple NTP (SNTP) client based on
+[RFC5905](https://tools.ietf.org/html/rfc5905). It allows you to connect to
+a remote NTP server and request information about the current time.
+
+
+## Querying the current time
+
+If all you care about is the current time according to a remote NTP server,
+simply use the `Time` function:
+```go
+time, err := ntp.Time("0.beevik-ntp.pool.ntp.org")
+```
+
+
+## Querying time metadata
+
+To obtain the current time as well as some additional metadata about the time,
+use the `Query` function:
+```go
+response, err := ntp.Query("0.beevik-ntp.pool.ntp.org")
+time := time.Now().Add(response.ClockOffset)
+```
+
+Alternatively, use the `QueryWithOptions` function if you want to change the
+default behavior used by the `Query` function:
+```go
+options := ntp.QueryOptions{ Timeout: 30*time.Second, TTL: 5 }
+response, err := ntp.QueryWithOptions("0.beevik-ntp.pool.ntp.org", options)
+time := time.Now().Add(response.ClockOffset)
+```
+
+The `Response` structure returned by `Query` includes the following
+information:
+* `Time`: The time the server transmitted its response, according to its own clock.
+* `ClockOffset`: The estimated offset of the local system clock relative to the server's clock. For a more accurate time reading, you may add this offset to any subsequent system clock reading.
+* `RTT`: An estimate of the round-trip-time delay between the client and the server.
+* `Precision`: The precision of the server's clock reading.
+* `Stratum`: The server's stratum, which indicates the number of hops from the server to the reference clock. A stratum 1 server is directly attached to the reference clock. If the stratum is zero, the server has responded with the "kiss of death".
+* `ReferenceID`: A unique identifier for the consulted reference clock.
+* `ReferenceTime`: The time at which the server last updated its local clock setting.
+* `RootDelay`: The server's aggregate round-trip-time delay to the stratum 1 server.
+* `RootDispersion`: The server's estimated maximum measurement error relative to the reference clock.
+* `RootDistance`: An estimate of the root synchronization distance between the client and the stratum 1 server.
+* `Leap`: The leap second indicator, indicating whether a second should be added to or removed from the current month's last minute.
+* `MinError`: A lower bound on the clock error between the client and the server.
+* `KissCode`: A 4-character string describing the reason for a "kiss of death" response (stratum=0).
+* `Poll`: The maximum polling interval between successive messages to the server.
+
+The `Response` structure's `Validate` method performs additional sanity checks
+to determine whether the response is suitable for time synchronization
+purposes.
+```go
+err := response.Validate()
+if err == nil {
+    // response data is suitable for synchronization purposes
+}
+```
+
+## Using the NTP pool
+
+The NTP pool is a shared resource used by people all over the world.
+To prevent it from becoming overloaded, please avoid querying the standard
+`pool.ntp.org` zone names in your applications.  Instead, consider requesting
+your own [vendor zone](http://www.pool.ntp.org/en/vendors.html) or [joining
+the pool](http://www.pool.ntp.org/join.html).

vendor/github.com/beevik/ntp/RELEASE_NOTES.md

+Release v0.2.0
+==============
+
+There are no breaking changes or further deprecations in this release.
+
+**Changes**
+
+* Added `KissCode` to the `Response` structure.
+
+
 Release v0.1.1
 ==============

vendor/github.com/beevik/ntp/ntp.go

@@ -14,6 +14,7 @@ import (
 	"crypto/rand"
 	"encoding/binary"
 	"errors"
+	"fmt"
 	"net"
 	"time"
@@ -223,6 +224,11 @@ type Response struct {
 	// minimum error may be useful.
 	MinError time.Duration
+	// KissCode is a 4-character string describing the reason for a
+	// "kiss of death" response (stratum = 0). For a list of standard kiss
+	// codes, see https://tools.ietf.org/html/rfc5905#section-7.4.
+	KissCode string
+
 	// Poll is the maximum interval between successive NTP polling messages.
 	// It is not relevant for simple NTP clients like this one.
 	Poll time.Duration
@@ -233,7 +239,7 @@ type Response struct {
 func (r *Response) Validate() error {
 	// Handle invalid stratum values.
 	if r.Stratum == 0 {
-		return errors.New("kiss of death received")
+		return fmt.Errorf("kiss of death received: %s", r.KissCode)
 	}
 	if r.Stratum >= maxStratum {
 		return errors.New("invalid stratum in response")
@@ -379,16 +385,16 @@ func getTime(host string, opt QueryOptions) (*msg, ntpTime, error) {
 	// To ensure privacy and prevent spoofing, try to use a random 64-bit
 	// value for the TransmitTime. If crypto/rand couldn't generate a
 	// random value, fall back to using the system clock. Keep track of
-	// when the messsage was actually sent.
-	r := make([]byte, 8)
-	_, err = rand.Read(r)
-	var sendTime time.Time
+	// when the messsage was actually transmitted.
+	bits := make([]byte, 8)
+	_, err = rand.Read(bits)
+	var xmitTime time.Time
 	if err == nil {
-		xmitMsg.TransmitTime = ntpTime(binary.BigEndian.Uint64(r))
-		sendTime = time.Now()
+		xmitMsg.TransmitTime = ntpTime(binary.BigEndian.Uint64(bits))
+		xmitTime = time.Now()
 	} else {
-		sendTime = time.Now()
-		xmitMsg.TransmitTime = toNtpTime(sendTime)
+		xmitTime = time.Now()
+		xmitMsg.TransmitTime = toNtpTime(xmitTime)
 	}
 	// Transmit the query.
@@ -404,15 +410,16 @@ func getTime(host string, opt QueryOptions) (*msg, ntpTime, error) {
 	}
 	// Keep track of the time the response was received.
-	delta := time.Since(sendTime)
+	delta := time.Since(xmitTime)
 	if delta < 0 {
-		// The system clock may have been set backwards since the packet was
-		// transmitted. In go 1.9 and later, time.Since ensures that a
-		// monotonic clock is used, and delta can never be less than zero.
-		// In versions before 1.9, we have to check.
+		// The local system may have had its clock adjusted since it
+		// sent the query. In go 1.9 and later, time.Since ensures
+		// that a monotonic clock is used, so delta can never be less
+		// than zero. In versions before 1.9, a monotonic clock is
+		// not used, so we have to check.
 		return nil, 0, errors.New("client clock ticked backwards")
 	}
-	recvTime := toNtpTime(sendTime.Add(delta))
+	recvTime := toNtpTime(xmitTime.Add(delta))
 	// Check for invalid fields.
 	if recvMsg.getMode() != server {
@@ -428,9 +435,9 @@ func getTime(host string, opt QueryOptions) (*msg, ntpTime, error) {
 		return nil, 0, errors.New("server clock ticked backwards")
 	}
-	// Correct the received message's origin time using the actual send
-	// time.
-	recvMsg.OriginTime = toNtpTime(sendTime)
+	// Correct the received message's origin time using the actual
+	// transmit time.
+	recvMsg.OriginTime = toNtpTime(xmitTime)
 	return recvMsg, recvTime, nil
 }
@@ -456,6 +463,12 @@ func parseTime(m *msg, recvTime ntpTime) *Response {
 	// Calculate values depending on other calculated values
 	r.RootDistance = rootDistance(r.RTT, r.RootDelay, r.RootDispersion)
+	// If a kiss of death was received, interpret the reference ID as
+	// a kiss code.
+	if r.Stratum == 0 {
+		r.KissCode = kissCode(r.ReferenceID)
+	}
+
 	return r
 }
@@ -533,3 +546,20 @@ func toInterval(t int8) time.Duration {
 		return time.Second
 	}
 }
+
+func kissCode(id uint32) string {
+	isPrintable := func(ch byte) bool { return ch >= 32 && ch <= 126 }
+
+	b := []byte{
+		byte(id >> 24),
+		byte(id >> 16),
+		byte(id >> 8),
+		byte(id),
+	}
+	for _, ch := range b {
+		if !isPrintable(ch) {
+			return ""
+		}
+	}
+	return string(b)
+}

vendor/github.com/mdlayher/genetlink/LICENSE.md

+MIT License
+===========
+
+Copyright (C) 2016-2017 Matt Layher
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/mdlayher/genetlink/README.md

+genetlink [![Build Status](https://travis-ci.org/mdlayher/genetlink.svg?branch=master)](https://travis-ci.org/mdlayher/genetlink) [![GoDoc](https://godoc.org/github.com/mdlayher/genetlink?status.svg)](https://godoc.org/github.com/mdlayher/genetlink) [![Go Report Card](https://goreportcard.com/badge/github.com/mdlayher/genetlink)](https://goreportcard.com/report/github.com/mdlayher/genetlink)
+=========
+
+Package `genetlink` implements generic netlink interactions and data types.
+MIT Licensed.
+
+For more information about how netlink and generic netlink work,
+check out my blog series on [Linux, Netlink, and Go](https://medium.com/@mdlayher/linux-netlink-and-go-part-1-netlink-4781aaeeaca8).
\ No newline at end of file

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

 package genetlink
-import "github.com/mdlayher/netlink"
-
-// Controller is the generic netlink controller family ID, used to issue
-// requests to the controller.
-const Controller = 0x10
+import (
+	"github.com/mdlayher/netlink"
+	"golang.org/x/net/bpf"
+)
 // Protocol is the netlink protocol constant used to specify generic netlink.
-const Protocol = 0x10
+const Protocol = 0x10 // unix.NETLINK_GENERIC
 // A Conn is a generic netlink connection.  A Conn can be used to send and
 // receive generic netlink messages to and from netlink.
 type Conn struct {
-	// Family provides functions to help retrieve generic netlink families.
-	Family *FamilyService
-
-	c conn
-}
-
-var _ conn = &netlink.Conn{}
-
-// A conn is a netlink connection, which can be swapped for tests.
-type conn interface {
-	Close() error
-	JoinGroup(group uint32) error
-	LeaveGroup(group uint32) error
-	Send(m netlink.Message) (netlink.Message, error)
-	Receive() ([]netlink.Message, error)
+	// Operating system-specific netlink connection.
+	c *netlink.Conn
 }
 // Dial dials a generic netlink connection.  Config specifies optional
@@ -38,18 +24,16 @@ func Dial(config *netlink.Config) (*Conn, error) {
 		return nil, err
 	}
-	return newConn(c), nil
+	return NewConn(c), nil
 }
-// newConn is the internal constructor for Conn, used in tests.
-func newConn(c conn) *Conn {
-	gc := &Conn{
-		c: c,
-	}
-
-	gc.Family = &FamilyService{c: gc}
-
-	return gc
+// NewConn creates a Conn that wraps an existing *netlink.Conn for
+// generic netlink communications.
+//
+// NewConn is primarily useful for tests. Most applications should use
+// Dial instead.
+func NewConn(c *netlink.Conn) *Conn {
+	return &Conn{c: c}
 }
 // Close closes the connection.
@@ -57,6 +41,17 @@ func (c *Conn) Close() error {
 	return c.c.Close()
 }
+// GetFamily retrieves a generic netlink family with the specified name.  If the
+// family does not exist, the error value can be checked using os.IsNotExist.
+func (c *Conn) GetFamily(name string) (Family, error) {
+	return c.getFamily(name)
+}
+
+// ListFamilies retrieves all registered generic netlink families.
+func (c *Conn) ListFamilies() ([]Family, error) {
+	return c.listFamilies()
+}
+
 // JoinGroup joins a netlink multicast group by its ID.
 func (c *Conn) JoinGroup(group uint32) error {
 	return c.c.JoinGroup(group)
@@ -67,6 +62,11 @@ func (c *Conn) LeaveGroup(group uint32) error {
 	return c.c.LeaveGroup(group)
 }
+// SetBPF attaches an assembled BPF program to a Conn.
+func (c *Conn) SetBPF(filter []bpf.RawInstruction) error {
+	return c.c.SetBPF(filter)
+}
+
 // 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.go

+package genetlink
+
+// A Family is a generic netlink family.
+type Family struct {
+	ID      uint16
+	Version uint8
+	Name    string
+	Groups  []MulticastGroup
+}
+
+// A MulticastGroup is a generic netlink multicast group, which can be joined
+// for notifications from generic netlink families when specific events take
+// place.
+type MulticastGroup struct {
+	ID   uint32
+	Name string
+}

vendor/github.com/mdlayher/netlink/genetlink/family.go → vendor/github.com/mdlayher/genetlink/family_linux.go

+//+build linux
+
 package genetlink
 import (
@@ -7,14 +9,7 @@ import (
 	"github.com/mdlayher/netlink"
 	"github.com/mdlayher/netlink/nlenc"
-)
-
-// Constants used to request information from generic netlink controller.
-// Reference: http://lxr.free-electrons.com/source/include/linux/genetlink.h?v=3.3#L35
-const (
-	ctrlVersion = 1
-
-	ctrlCommandGetFamily = 3
+	"golang.org/x/sys/unix"
 )
 var (
@@ -27,32 +22,10 @@ var (
 	errInvalidMulticastGroupArray = errors.New("invalid multicast group attribute array")
 )
-// A Family is a generic netlink family.
-type Family struct {
-	ID      uint16
-	Version uint8
-	Name    string
-	Groups  []MulticastGroup
-}
-
-// A MulticastGroup is a generic netlink multicast group, which can be joined
-// for notifications from generic netlink families when specific events take
-// place.
-type MulticastGroup struct {
-	ID   uint32
-	Name string
-}
-
-// A FamilyService is used to retrieve generic netlink family information.
-type FamilyService struct {
-	c *Conn
-}
-
-// Get retrieves a generic netlink family with the specified name.  If the
-// family does not exist, the error value can be checked using os.IsNotExist.
-func (s *FamilyService) Get(name string) (Family, error) {
+// getFamily retrieves a generic netlink family with the specified name.
+func (c *Conn) getFamily(name string) (Family, error) {
 	b, err := netlink.MarshalAttributes([]netlink.Attribute{{
-		Type: attrFamilyName,
+		Type: unix.CTRL_ATTR_FAMILY_NAME,
 		Data: nlenc.Bytes(name),
 	}})
 	if err != nil {
@@ -61,13 +34,14 @@ func (s *FamilyService) Get(name string) (Family, error) {
 	req := Message{
 		Header: Header{
-			Command: ctrlCommandGetFamily,
-			Version: ctrlVersion,
+			Command: unix.CTRL_CMD_GETFAMILY,
+			// TODO(mdlayher): grab nlctrl version?
+			Version: 1,
 		},
 		Data: b,
 	}
-	msgs, err := s.c.Execute(req, Controller, netlink.HeaderFlagsRequest)
+	msgs, err := c.Execute(req, unix.GENL_ID_CTRL, netlink.HeaderFlagsRequest)
 	if err != nil {
 		return Family{}, err
 	}
@@ -87,17 +61,18 @@ func (s *FamilyService) Get(name string) (Family, error) {
 	return families[0], nil
 }
-// List retrieves all registered generic netlink families.
-func (s *FamilyService) List() ([]Family, error) {
+// listFamilies retrieves all registered generic netlink families.
+func (c *Conn) listFamilies() ([]Family, error) {
 	req := Message{
 		Header: Header{
-			Command: ctrlCommandGetFamily,
-			Version: ctrlVersion,
+			Command: unix.CTRL_CMD_GETFAMILY,
+			// TODO(mdlayher): grab nlctrl version?
+			Version: 1,
 		},
 	}
 	flags := netlink.HeaderFlagsRequest | netlink.HeaderFlagsDump
-	msgs, err := s.c.Execute(req, Controller, flags)
+	msgs, err := c.Execute(req, unix.GENL_ID_CTRL, flags)
 	if err != nil {
 		return nil, err
 	}
@@ -126,38 +101,22 @@ func buildFamilies(msgs []Message) ([]Family, error) {
 	return families, nil
 }
-// Attribute IDs mapped to specific family fields.
-const (
-	// TODO(mdlayher): parse additional attributes
-
-	// Family attributes
-	attrUnspecified     = 0
-	attrFamilyID        = 1
-	attrFamilyName      = 2
-	attrVersion         = 3
-	attrMulticastGroups = 7
-
-	// Multicast group-specific attributes
-	attrMGName = 1
-	attrMGID   = 2
-)
-
 // parseAttributes parses netlink attributes into a Family's fields.
 func (f *Family) parseAttributes(attrs []netlink.Attribute) error {
 	for _, a := range attrs {
 		switch a.Type {
-		case attrFamilyID:
+		case unix.CTRL_ATTR_FAMILY_ID:
 			f.ID = nlenc.Uint16(a.Data)
-		case attrFamilyName:
+		case unix.CTRL_ATTR_FAMILY_NAME:
 			f.Name = nlenc.String(a.Data)
-		case attrVersion:
+		case unix.CTRL_ATTR_VERSION:
 			v := nlenc.Uint32(a.Data)
 			if v > math.MaxUint8 {
 				return errInvalidFamilyVersion
 			}
 			f.Version = uint8(v)
-		case attrMulticastGroups:
+		case unix.CTRL_ATTR_MCAST_GROUPS:
 			groups, err := parseMulticastGroups(a.Data)
 			if err != nil {
 				return err
@@ -194,9 +153,9 @@ func parseMulticastGroups(b []byte) ([]MulticastGroup, error) {
 		var g MulticastGroup
 		for _, na := range nattrs {
 			switch na.Type {
-			case attrMGName:
+			case unix.CTRL_ATTR_MCAST_GRP_NAME:
 				g.Name = nlenc.String(na.Data)
-			case attrMGID:
+			case unix.CTRL_ATTR_MCAST_GRP_ID:
 				g.ID = nlenc.Uint32(na.Data)
 			}
 		}

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

+//+build !linux
+
+package genetlink
+
+import (
+	"fmt"
+	"runtime"
+)
+
+var (
+	// errUnimplemented is returned by all functions on platforms that
+	// cannot make use of generic netlink.
+	errUnimplemented = fmt.Errorf("generic netlink not implemented on %s/%s",
+		runtime.GOOS, runtime.GOARCH)
+)
+
+// getFamily always returns an error.
+func (c *Conn) getFamily(name string) (Family, error) {
+	return Family{}, errUnimplemented
+}
+
+// listFamilies always returns an error.
+func (c *Conn) listFamilies() ([]Family, error) {
+	return nil, errUnimplemented
+}

vendor/github.com/mdlayher/netlink/genetlink/message.go → vendor/github.com/mdlayher/genetlink/message.go

@@ -20,7 +20,7 @@ type Header struct {
 }
 // headerLen is the length of a Header.
-const headerLen = 4
+const headerLen = 4 // unix.GENL_HDRLEN
 // A Message is a generic netlink message.  It contains a Header and an
 // arbitrary byte payload, which may be decoded using information from the

vendor/github.com/mdlayher/netlink/LICENSE.md

 MIT License
 ===========
-Copyright (C) 2016 Matt Layher
+Copyright (C) 2016-2017 Matt Layher
 Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

vendor/github.com/mdlayher/netlink/README.md

@@ -4,6 +4,12 @@ netlink [![Build Status](https://travis-ci.org/mdlayher/netlink.svg?branch=maste
 Package `netlink` provides low-level access to Linux netlink sockets.
 MIT Licensed.
+For more information about how netlink works, check out my blog series
+on [Linux, Netlink, and Go](https://medium.com/@mdlayher/linux-netlink-and-go-part-1-netlink-4781aaeeaca8).
+
+If you're looking for package `genetlink`, it's been moved to its own
+repository at [`github.com/mdlayher/genetlink`](https://github.com/mdlayher/genetlink).
+
 Why?
 ----
@@ -18,4 +24,4 @@ I wanted in a netlink package:
 - Doesn't need root to work
 My goal for this package is to use it as a building block for the creation
-of other netlink protocol family packages.
+of other netlink family packages.

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

@@ -9,10 +9,13 @@ 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
-// to and from the Data field of Message for some netlink protocol families.
+// to and from the Data field of Message for some netlink families.
 type Attribute struct {
 	// Length of an Attribute, including this field and Type.
 	Length uint16
@@ -22,19 +25,50 @@ 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)
-	nlenc.PutUint16(b[2:4], a.Type)
-	copy(b[4:], a.Data)
+
+	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)
+	}
+
+	copy(b[nlaHeaderLen:], a.Data)
 	return b, nil
 }
@@ -46,23 +80,33 @@ func (a *Attribute) UnmarshalBinary(b []byte) error {
 	}
 	a.Length = nlenc.Uint16(b[0:2])
-	a.Type = nlenc.Uint16(b[2:4])
+
+	// 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
 	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:
 		a.Data = make([]byte, 0)
 	// Not enough length for any data
-	case a.Length < 4:
+	case int(a.Length) < nlaHeaderLen:
 		return errInvalidAttribute
 	// Data present
-	case a.Length >= 4:
-		a.Data = make([]byte, len(b[4:a.Length]))
-		copy(a.Data, b[4:a.Length])
+	case int(a.Length) >= nlaHeaderLen:
+		a.Data = make([]byte, len(b[nlaHeaderLen:a.Length]))
+		copy(a.Data, b[nlaHeaderLen:a.Length])
 	}
 	return nil

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

@@ -2,7 +2,9 @@ package netlink
 import (
 	"errors"
+	"io"
 	"math/rand"
+	"os"
 	"sync/atomic"
 	"golang.org/x/net/bpf"
@@ -15,12 +17,20 @@ var (
 	errShortErrorMessage  = errors.New("not enough data for netlink error code")
 )
+// Errors which can be returned by a Socket that does not implement
+// all exposed methods of Conn.
+var (
+	errReadWriteCloserNotSupported = errors.New("raw read/write/closer not supported")
+	errMulticastGroupsNotSupported = errors.New("multicast groups not supported")
+	errBPFFiltersNotSupported      = errors.New("BPF filters not supported")
+)
+
 // A Conn is a connection to netlink.  A Conn can be used to send and
 // receives messages to and from netlink.
 type Conn struct {
-	// osConn is the operating system-specific implementation of
+	// sock is the operating system-specific implementation of
 	// a netlink sockets connection.
-	c osConn
+	sock Socket
 	// seq is an atomically incremented integer used to provide sequence
 	// numbers when Conn.Send is called.
@@ -30,44 +40,45 @@ type Conn struct {
 	pid uint32
 }
-// An osConn is an operating-system specific implementation of netlink
+// A Socket is an operating-system specific implementation of netlink
 // sockets used by Conn.
-type osConn interface {
+type Socket interface {
 	Close() error
 	Send(m Message) error
 	Receive() ([]Message, error)
-	JoinGroup(group uint32) error
-	LeaveGroup(group uint32) error
-	SetBPF(filter []bpf.RawInstruction) error
 }
-// Dial dials a connection to netlink, using the specified protocol number.
+// Dial dials a connection to netlink, using the specified netlink family.
 // Config specifies optional configuration for Conn.  If config is nil, a default
 // configuration will be used.
-func Dial(proto int, config *Config) (*Conn, error) {
-	// Use OS-specific dial() to create osConn
-	c, pid, err := dial(proto, config)
+func Dial(family int, config *Config) (*Conn, error) {
+	// Use OS-specific dial() to create Socket
+	c, pid, err := dial(family, config)
 	if err != nil {
 		return nil, err
 	}
-	return newConn(c, pid), nil
+	return NewConn(c, pid), nil
 }
-// newConn is the internal constructor for Conn, used in tests.
-func newConn(c osConn, pid uint32) *Conn {
+// NewConn creates a Conn using the specified Socket and PID for netlink
+// communications.
+//
+// NewConn is primarily useful for tests. Most applications should use
+// Dial instead.
+func NewConn(c Socket, pid uint32) *Conn {
 	seq := rand.Uint32()
 	return &Conn{
-		c:   c,
-		seq: &seq,
-		pid: pid,
+		sock: c,
+		seq:  &seq,
+		pid:  pid,
 	}
 }
 // Close closes the connection.
 func (c *Conn) Close() error {
-	return c.c.Close()
+	return c.sock.Close()
 }
 // Execute sends a single Message to netlink using Conn.Send, receives one or more
@@ -127,7 +138,7 @@ func (c *Conn) Send(m Message) (Message, error) {
 		m.Header.PID = c.pid
 	}
-	if err := c.c.Send(m); err != nil {
+	if err := c.sock.Send(m); err != nil {
 		return Message{}, err
 	}
@@ -145,8 +156,13 @@ func (c *Conn) Receive() ([]Message, error) {
 		return nil, err
 	}
+	// When using nltest, it's possible for zero messages to be returned by receive.
+	if len(msgs) == 0 {
+		return msgs, nil
+	}
+
 	// Trim the final message with multi-part done indicator if
-	// present
+	// present.
 	if m := msgs[len(msgs)-1]; m.Header.Flags&HeaderFlagsMulti != 0 && m.Header.Type == HeaderTypeDone {
 		return msgs[:len(msgs)-1], nil
 	}
@@ -157,7 +173,7 @@ 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.c.Receive()
+	msgs, err := c.sock.Receive()
 	if err != nil {
 		return nil, err
 	}
@@ -190,19 +206,93 @@ func (c *Conn) receive() ([]Message, error) {
 	return append(msgs, mmsgs...), nil
 }
+// An fder is a Socket that supports retrieving its raw file descriptor.
+type fder interface {
+	Socket
+	FD() int
+}
+
+var _ io.ReadWriteCloser = &fileReadWriteCloser{}
+
+// A fileReadWriteCloser is a limited *os.File which only allows access to its
+// Read and Write methods.
+type fileReadWriteCloser struct {
+	f *os.File
+}
+
+// Read implements io.ReadWriteCloser.
+func (rwc *fileReadWriteCloser) Read(b []byte) (int, error) { return rwc.f.Read(b) }
+
+// Write implements io.ReadWriteCloser.
+func (rwc *fileReadWriteCloser) Write(b []byte) (int, error) { return rwc.f.Write(b) }
+
+// Close implements io.ReadWriteCloser.
+func (rwc *fileReadWriteCloser) Close() error { return rwc.f.Close() }
+
+// ReadWriteCloser returns a raw io.ReadWriteCloser backed by the connection
+// of the Conn.
+//
+// ReadWriteCloser is intended for advanced use cases, such as those that do
+// not involve standard netlink message passing.
+//
+// Once invoked, it is the caller's responsibility to ensure that operations
+// performed using Conn and the raw io.ReadWriteCloser do not conflict with
+// each other.  In almost all scenarios, only one of the two should be used.
+func (c *Conn) ReadWriteCloser() (io.ReadWriteCloser, error) {
+	fc, ok := c.sock.(fder)
+	if !ok {
+		return nil, errReadWriteCloserNotSupported
+	}
+
+	return &fileReadWriteCloser{
+		// Backing the io.ReadWriteCloser with an *os.File enables easy reading
+		// and writing without more system call boilerplate.
+		f: os.NewFile(uintptr(fc.FD()), "netlink"),
+	}, nil
+}
+
+// A groupJoinLeaver is a Socket that supports joining and leaving
+// netlink multicast groups.
+type groupJoinLeaver interface {
+	Socket
+	JoinGroup(group uint32) error
+	LeaveGroup(group uint32) error
+}
+
 // JoinGroup joins a netlink multicast group by its ID.
 func (c *Conn) JoinGroup(group uint32) error {
-	return c.c.JoinGroup(group)
+	gc, ok := c.sock.(groupJoinLeaver)
+	if !ok {
+		return errMulticastGroupsNotSupported
+	}
+
+	return gc.JoinGroup(group)
 }
 // LeaveGroup leaves a netlink multicast group by its ID.
 func (c *Conn) LeaveGroup(group uint32) error {
-	return c.c.LeaveGroup(group)
+	gc, ok := c.sock.(groupJoinLeaver)
+	if !ok {
+		return errMulticastGroupsNotSupported
+	}
+
+	return gc.LeaveGroup(group)
+}
+
+// A bpfSetter is a Socket that supports setting BPF filters.
+type bpfSetter interface {
+	Socket
+	bpf.Setter
 }
 // SetBPF attaches an assembled BPF program to a Conn.
 func (c *Conn) SetBPF(filter []bpf.RawInstruction) error {
-	return c.c.SetBPF(filter)
+	bc, ok := c.sock.(bpfSetter)
+	if !ok {
+		return errBPFFiltersNotSupported
+	}
+
+	return bc.SetBPF(filter)
 }
 // nextSequence atomically increments Conn's sequence number and returns

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

@@ -17,7 +17,7 @@ var (
 	errInvalidFamily   = errors.New("received invalid netlink family")
 )
-var _ osConn = &conn{}
+var _ Socket = &conn{}
 // A conn is the Linux implementation of a netlink sockets connection.
 type conn struct {
@@ -29,6 +29,7 @@ type conn struct {
 type socket interface {
 	Bind(sa unix.Sockaddr) error
 	Close() error
+	FD() int
 	Getsockname() (unix.Sockaddr, error)
 	Recvmsg(p, oob []byte, flags int) (n int, oobn int, recvflags int, from unix.Sockaddr, err error)
 	Sendmsg(p, oob []byte, to unix.Sockaddr, flags int) error
@@ -154,6 +155,11 @@ func (c *conn) Close() error {
 	return c.s.Close()
 }
+// FD retrieves the file descriptor of the Conn.
+func (c *conn) FD() int {
+	return c.s.FD()
+}
+
 // JoinGroup joins a multicast group by ID.
 func (c *conn) JoinGroup(group uint32) error {
 	return c.s.SetSockopt(
@@ -211,6 +217,7 @@ type sysSocket struct {
 func (s *sysSocket) Bind(sa unix.Sockaddr) error         { return unix.Bind(s.fd, sa) }
 func (s *sysSocket) Close() error                        { return unix.Close(s.fd) }
+func (s *sysSocket) FD() int                             { return s.fd }
 func (s *sysSocket) Getsockname() (unix.Sockaddr, error) { return unix.Getsockname(s.fd) }
 func (s *sysSocket) Recvmsg(p, oob []byte, flags int) (int, int, int, unix.Sockaddr, error) {
 	return unix.Recvmsg(s.fd, p, oob, flags)

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

@@ -16,14 +16,14 @@ var (
 		runtime.GOOS, runtime.GOARCH)
 )
-var _ osConn = &conn{}
+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, error) {
-	return nil, errUnimplemented
+func dial(family int, config *Config) (*conn, uint32, error) {
+	return nil, 0, errUnimplemented
 }
 // Send always returns an error.

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

@@ -5,6 +5,16 @@ import (
 	"unsafe"
 )
+// PutUint8 encodes a uint8 into b.
+// If b is not exactly 1 byte in length, PutUint8 will panic.
+func PutUint8(b []byte, v uint8) {
+	if l := len(b); l != 1 {
+		panic(fmt.Sprintf("PutUint8: unexpected byte slice length: %d", l))
+	}
+
+	b[0] = v
+}
+
 // PutUint16 encodes a uint16 into b using the host machine's native endianness.
 // If b is not exactly 2 bytes in length, PutUint16 will panic.
 func PutUint16(b []byte, v uint16) {
@@ -35,6 +45,26 @@ func PutUint64(b []byte, v uint64) {
 	*(*uint64)(unsafe.Pointer(&b[0])) = v
 }
+// PutInt32 encodes a int32 into b using the host machine's native endianness.
+// If b is not exactly 4 bytes in length, PutInt32 will panic.
+func PutInt32(b []byte, v int32) {
+	if l := len(b); l != 4 {
+		panic(fmt.Sprintf("PutInt32: unexpected byte slice length: %d", l))
+	}
+
+	*(*int32)(unsafe.Pointer(&b[0])) = v
+}
+
+// Uint8 decodes a uint8 from b.
+// If b is not exactly 1 byte in length, Uint8 will panic.
+func Uint8(b []byte) uint8 {
+	if l := len(b); l != 1 {
+		panic(fmt.Sprintf("Uint8: unexpected byte slice length: %d", l))
+	}
+
+	return b[0]
+}
+
 // Uint16 decodes a uint16 from b using the host machine's native endianness.
 // If b is not exactly 2 bytes in length, Uint16 will panic.
 func Uint16(b []byte) uint16 {
@@ -75,6 +105,14 @@ func Int32(b []byte) int32 {
 	return *(*int32)(unsafe.Pointer(&b[0]))
 }
+// Uint8Bytes encodes a uint8 into a newly-allocated byte slice. It is a
+// shortcut for allocating a new byte slice and filling it using PutUint8.
+func Uint8Bytes(v uint8) []byte {
+	b := make([]byte, 1)
+	PutUint8(b, v)
+	return b
+}
+
 // Uint16Bytes encodes a uint16 into a newly-allocated byte slice using the
 // host machine's native endianness.  It is a shortcut for allocating a new
 // byte slice and filling it using PutUint16.
@@ -101,3 +139,12 @@ func Uint64Bytes(v uint64) []byte {
 	PutUint64(b, v)
 	return b
 }
+
+// Int32Bytes encodes a int32 into a newly-allocated byte slice using the
+// host machine's native endianness.  It is a shortcut for allocating a new
+// byte slice and filling it using PutInt32.
+func Int32Bytes(v int32) []byte {
+	b := make([]byte, 4)
+	PutInt32(b, v)
+	return b
+}