diff --git a/vendor/github.com/google/gopacket/packet.go b/vendor/github.com/google/gopacket/packet.go
new file mode 100644
index 0000000..3a7c4b3
--- /dev/null
+++ b/vendor/github.com/google/gopacket/packet.go
@@ -0,0 +1,864 @@
+// Copyright 2012 Google, Inc. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree.
+
+package gopacket
+
+import (
+	"bytes"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"reflect"
+	"runtime/debug"
+	"strings"
+	"syscall"
+	"time"
+)
+
+// CaptureInfo provides standardized information about a packet captured off
+// the wire or read from a file.
+type CaptureInfo struct {
+	// Timestamp is the time the packet was captured, if that is known.
+	Timestamp time.Time
+	// CaptureLength is the total number of bytes read off of the wire.
+	CaptureLength int
+	// Length is the size of the original packet.  Should always be >=
+	// CaptureLength.
+	Length int
+	// InterfaceIndex
+	InterfaceIndex int
+	// The packet source can place ancillary data of various types here.
+	// For example, the afpacket source can report the VLAN of captured
+	// packets this way.
+	AncillaryData []interface{}
+}
+
+// PacketMetadata contains metadata for a packet.
+type PacketMetadata struct {
+	CaptureInfo
+	// Truncated is true if packet decoding logic detects that there are fewer
+	// bytes in the packet than are detailed in various headers (for example, if
+	// the number of bytes in the IPv4 contents/payload is less than IPv4.Length).
+	// This is also set automatically for packets captured off the wire if
+	// CaptureInfo.CaptureLength < CaptureInfo.Length.
+	Truncated bool
+}
+
+// Packet is the primary object used by gopacket.  Packets are created by a
+// Decoder's Decode call.  A packet is made up of a set of Data, which
+// is broken into a number of Layers as it is decoded.
+type Packet interface {
+	//// Functions for outputting the packet as a human-readable string:
+	//// ------------------------------------------------------------------
+	// String returns a human-readable string representation of the packet.
+	// It uses LayerString on each layer to output the layer.
+	String() string
+	// Dump returns a verbose human-readable string representation of the packet,
+	// including a hex dump of all layers.  It uses LayerDump on each layer to
+	// output the layer.
+	Dump() string
+
+	//// Functions for accessing arbitrary packet layers:
+	//// ------------------------------------------------------------------
+	// Layers returns all layers in this packet, computing them as necessary
+	Layers() []Layer
+	// Layer returns the first layer in this packet of the given type, or nil
+	Layer(LayerType) Layer
+	// LayerClass returns the first layer in this packet of the given class,
+	// or nil.
+	LayerClass(LayerClass) Layer
+
+	//// Functions for accessing specific types of packet layers.  These functions
+	//// return the first layer of each type found within the packet.
+	//// ------------------------------------------------------------------
+	// LinkLayer returns the first link layer in the packet
+	LinkLayer() LinkLayer
+	// NetworkLayer returns the first network layer in the packet
+	NetworkLayer() NetworkLayer
+	// TransportLayer returns the first transport layer in the packet
+	TransportLayer() TransportLayer
+	// ApplicationLayer returns the first application layer in the packet
+	ApplicationLayer() ApplicationLayer
+	// ErrorLayer is particularly useful, since it returns nil if the packet
+	// was fully decoded successfully, and non-nil if an error was encountered
+	// in decoding and the packet was only partially decoded.  Thus, its output
+	// can be used to determine if the entire packet was able to be decoded.
+	ErrorLayer() ErrorLayer
+
+	//// Functions for accessing data specific to the packet:
+	//// ------------------------------------------------------------------
+	// Data returns the set of bytes that make up this entire packet.
+	Data() []byte
+	// Metadata returns packet metadata associated with this packet.
+	Metadata() *PacketMetadata
+}
+
+// packet contains all the information we need to fulfill the Packet interface,
+// and its two "subclasses" (yes, no such thing in Go, bear with me),
+// eagerPacket and lazyPacket, provide eager and lazy decoding logic around the
+// various functions needed to access this information.
+type packet struct {
+	// data contains the entire packet data for a packet
+	data []byte
+	// initialLayers is space for an initial set of layers already created inside
+	// the packet.
+	initialLayers [6]Layer
+	// layers contains each layer we've already decoded
+	layers []Layer
+	// last is the last layer added to the packet
+	last Layer
+	// metadata is the PacketMetadata for this packet
+	metadata PacketMetadata
+
+	decodeOptions DecodeOptions
+
+	// Pointers to the various important layers
+	link        LinkLayer
+	network     NetworkLayer
+	transport   TransportLayer
+	application ApplicationLayer
+	failure     ErrorLayer
+}
+
+func (p *packet) SetTruncated() {
+	p.metadata.Truncated = true
+}
+
+func (p *packet) SetLinkLayer(l LinkLayer) {
+	if p.link == nil {
+		p.link = l
+	}
+}
+
+func (p *packet) SetNetworkLayer(l NetworkLayer) {
+	if p.network == nil {
+		p.network = l
+	}
+}
+
+func (p *packet) SetTransportLayer(l TransportLayer) {
+	if p.transport == nil {
+		p.transport = l
+	}
+}
+
+func (p *packet) SetApplicationLayer(l ApplicationLayer) {
+	if p.application == nil {
+		p.application = l
+	}
+}
+
+func (p *packet) SetErrorLayer(l ErrorLayer) {
+	if p.failure == nil {
+		p.failure = l
+	}
+}
+
+func (p *packet) AddLayer(l Layer) {
+	p.layers = append(p.layers, l)
+	p.last = l
+}
+
+func (p *packet) DumpPacketData() {
+	fmt.Fprint(os.Stderr, p.packetDump())
+	os.Stderr.Sync()
+}
+
+func (p *packet) Metadata() *PacketMetadata {
+	return &p.metadata
+}
+
+func (p *packet) Data() []byte {
+	return p.data
+}
+
+func (p *packet) DecodeOptions() *DecodeOptions {
+	return &p.decodeOptions
+}
+
+func (p *packet) addFinalDecodeError(err error, stack []byte) {
+	fail := &DecodeFailure{err: err, stack: stack}
+	if p.last == nil {
+		fail.data = p.data
+	} else {
+		fail.data = p.last.LayerPayload()
+	}
+	p.AddLayer(fail)
+	p.SetErrorLayer(fail)
+}
+
+func (p *packet) recoverDecodeError() {
+	if !p.decodeOptions.SkipDecodeRecovery {
+		if r := recover(); r != nil {
+			p.addFinalDecodeError(fmt.Errorf("%v", r), debug.Stack())
+		}
+	}
+}
+
+// LayerString outputs an individual layer as a string.  The layer is output
+// in a single line, with no trailing newline.  This function is specifically
+// designed to do the right thing for most layers... it follows the following
+// rules:
+//  * If the Layer has a String function, just output that.
+//  * Otherwise, output all exported fields in the layer, recursing into
+//    exported slices and structs.
+// NOTE:  This is NOT THE SAME AS fmt's "%#v".  %#v will output both exported
+// and unexported fields... many times packet layers contain unexported stuff
+// that would just mess up the output of the layer, see for example the
+// Payload layer and it's internal 'data' field, which contains a large byte
+// array that would really mess up formatting.
+func LayerString(l Layer) string {
+	return fmt.Sprintf("%v\t%s", l.LayerType(), layerString(reflect.ValueOf(l), false, false))
+}
+
+// Dumper dumps verbose information on a value.  If a layer type implements
+// Dumper, then its LayerDump() string will include the results in its output.
+type Dumper interface {
+	Dump() string
+}
+
+// LayerDump outputs a very verbose string representation of a layer.  Its
+// output is a concatenation of LayerString(l) and hex.Dump(l.LayerContents()).
+// It contains newlines and ends with a newline.
+func LayerDump(l Layer) string {
+	var b bytes.Buffer
+	b.WriteString(LayerString(l))
+	b.WriteByte('\n')
+	if d, ok := l.(Dumper); ok {
+		dump := d.Dump()
+		if dump != "" {
+			b.WriteString(dump)
+			if dump[len(dump)-1] != '\n' {
+				b.WriteByte('\n')
+			}
+		}
+	}
+	b.WriteString(hex.Dump(l.LayerContents()))
+	return b.String()
+}
+
+// layerString outputs, recursively, a layer in a "smart" way.  See docs for
+// LayerString for more details.
+//
+// Params:
+//   i - value to write out
+//   anonymous:  if we're currently recursing an anonymous member of a struct
+//   writeSpace:  if we've already written a value in a struct, and need to
+//     write a space before writing more.  This happens when we write various
+//     anonymous values, and need to keep writing more.
+func layerString(v reflect.Value, anonymous bool, writeSpace bool) string {
+	// Let String() functions take precedence.
+	if v.CanInterface() {
+		if s, ok := v.Interface().(fmt.Stringer); ok {
+			return s.String()
+		}
+	}
+	// Reflect, and spit out all the exported fields as key=value.
+	switch v.Type().Kind() {
+	case reflect.Interface, reflect.Ptr:
+		if v.IsNil() {
+			return "nil"
+		}
+		r := v.Elem()
+		return layerString(r, anonymous, writeSpace)
+	case reflect.Struct:
+		var b bytes.Buffer
+		typ := v.Type()
+		if !anonymous {
+			b.WriteByte('{')
+		}
+		for i := 0; i < v.NumField(); i++ {
+			// Check if this is upper-case.
+			ftype := typ.Field(i)
+			f := v.Field(i)
+			if ftype.Anonymous {
+				anonStr := layerString(f, true, writeSpace)
+				writeSpace = writeSpace || anonStr != ""
+				b.WriteString(anonStr)
+			} else if ftype.PkgPath == "" { // exported
+				if writeSpace {
+					b.WriteByte(' ')
+				}
+				writeSpace = true
+				fmt.Fprintf(&b, "%s=%s", typ.Field(i).Name, layerString(f, false, writeSpace))
+			}
+		}
+		if !anonymous {
+			b.WriteByte('}')
+		}
+		return b.String()
+	case reflect.Slice:
+		var b bytes.Buffer
+		b.WriteByte('[')
+		if v.Len() > 4 {
+			fmt.Fprintf(&b, "..%d..", v.Len())
+		} else {
+			for j := 0; j < v.Len(); j++ {
+				if j != 0 {
+					b.WriteString(", ")
+				}
+				b.WriteString(layerString(v.Index(j), false, false))
+			}
+		}
+		b.WriteByte(']')
+		return b.String()
+	}
+	return fmt.Sprintf("%v", v.Interface())
+}
+
+const (
+	longBytesLength = 128
+)
+
+// LongBytesGoString returns a string representation of the byte slice shortened
+// using the format '<type>{<truncated slice> ... (<n> bytes)}' if it
+// exceeds a predetermined length. Can be used to avoid filling the display with
+// very long byte strings.
+func LongBytesGoString(buf []byte) string {
+	if len(buf) < longBytesLength {
+		return fmt.Sprintf("%#v", buf)
+	}
+	s := fmt.Sprintf("%#v", buf[:longBytesLength-1])
+	s = strings.TrimSuffix(s, "}")
+	return fmt.Sprintf("%s ... (%d bytes)}", s, len(buf))
+}
+
+func baseLayerString(value reflect.Value) string {
+	t := value.Type()
+	content := value.Field(0)
+	c := make([]byte, content.Len())
+	for i := range c {
+		c[i] = byte(content.Index(i).Uint())
+	}
+	payload := value.Field(1)
+	p := make([]byte, payload.Len())
+	for i := range p {
+		p[i] = byte(payload.Index(i).Uint())
+	}
+	return fmt.Sprintf("%s{Contents:%s, Payload:%s}", t.String(),
+		LongBytesGoString(c),
+		LongBytesGoString(p))
+}
+
+func layerGoString(i interface{}, b *bytes.Buffer) {
+	if s, ok := i.(fmt.GoStringer); ok {
+		b.WriteString(s.GoString())
+		return
+	}
+
+	var v reflect.Value
+	var ok bool
+	if v, ok = i.(reflect.Value); !ok {
+		v = reflect.ValueOf(i)
+	}
+	switch v.Kind() {
+	case reflect.Ptr, reflect.Interface:
+		if v.Kind() == reflect.Ptr {
+			b.WriteByte('&')
+		}
+		layerGoString(v.Elem().Interface(), b)
+	case reflect.Struct:
+		t := v.Type()
+		b.WriteString(t.String())
+		b.WriteByte('{')
+		for i := 0; i < v.NumField(); i++ {
+			if i > 0 {
+				b.WriteString(", ")
+			}
+			if t.Field(i).Name == "BaseLayer" {
+				fmt.Fprintf(b, "BaseLayer:%s", baseLayerString(v.Field(i)))
+			} else if v.Field(i).Kind() == reflect.Struct {
+				fmt.Fprintf(b, "%s:", t.Field(i).Name)
+				layerGoString(v.Field(i), b)
+			} else if v.Field(i).Kind() == reflect.Ptr {
+				b.WriteByte('&')
+				layerGoString(v.Field(i), b)
+			} else {
+				fmt.Fprintf(b, "%s:%#v", t.Field(i).Name, v.Field(i))
+			}
+		}
+		b.WriteByte('}')
+	default:
+		fmt.Fprintf(b, "%#v", i)
+	}
+}
+
+// LayerGoString returns a representation of the layer in Go syntax,
+// taking care to shorten "very long" BaseLayer byte slices
+func LayerGoString(l Layer) string {
+	b := new(bytes.Buffer)
+	layerGoString(l, b)
+	return b.String()
+}
+
+func (p *packet) packetString() string {
+	var b bytes.Buffer
+	fmt.Fprintf(&b, "PACKET: %d bytes", len(p.Data()))
+	if p.metadata.Truncated {
+		b.WriteString(", truncated")
+	}
+	if p.metadata.Length > 0 {
+		fmt.Fprintf(&b, ", wire length %d cap length %d", p.metadata.Length, p.metadata.CaptureLength)
+	}
+	if !p.metadata.Timestamp.IsZero() {
+		fmt.Fprintf(&b, " @ %v", p.metadata.Timestamp)
+	}
+	b.WriteByte('\n')
+	for i, l := range p.layers {
+		fmt.Fprintf(&b, "- Layer %d (%02d bytes) = %s\n", i+1, len(l.LayerContents()), LayerString(l))
+	}
+	return b.String()
+}
+
+func (p *packet) packetDump() string {
+	var b bytes.Buffer
+	fmt.Fprintf(&b, "-- FULL PACKET DATA (%d bytes) ------------------------------------\n%s", len(p.data), hex.Dump(p.data))
+	for i, l := range p.layers {
+		fmt.Fprintf(&b, "--- Layer %d ---\n%s", i+1, LayerDump(l))
+	}
+	return b.String()
+}
+
+// eagerPacket is a packet implementation that does eager decoding.  Upon
+// initial construction, it decodes all the layers it can from packet data.
+// eagerPacket implements Packet and PacketBuilder.
+type eagerPacket struct {
+	packet
+}
+
+var errNilDecoder = errors.New("NextDecoder passed nil decoder, probably an unsupported decode type")
+
+func (p *eagerPacket) NextDecoder(next Decoder) error {
+	if next == nil {
+		return errNilDecoder
+	}
+	if p.last == nil {
+		return errors.New("NextDecoder called, but no layers added yet")
+	}
+	d := p.last.LayerPayload()
+	if len(d) == 0 {
+		return nil
+	}
+	// Since we're eager, immediately call the next decoder.
+	return next.Decode(d, p)
+}
+func (p *eagerPacket) initialDecode(dec Decoder) {
+	defer p.recoverDecodeError()
+	err := dec.Decode(p.data, p)
+	if err != nil {
+		p.addFinalDecodeError(err, nil)
+	}
+}
+func (p *eagerPacket) LinkLayer() LinkLayer {
+	return p.link
+}
+func (p *eagerPacket) NetworkLayer() NetworkLayer {
+	return p.network
+}
+func (p *eagerPacket) TransportLayer() TransportLayer {
+	return p.transport
+}
+func (p *eagerPacket) ApplicationLayer() ApplicationLayer {
+	return p.application
+}
+func (p *eagerPacket) ErrorLayer() ErrorLayer {
+	return p.failure
+}
+func (p *eagerPacket) Layers() []Layer {
+	return p.layers
+}
+func (p *eagerPacket) Layer(t LayerType) Layer {
+	for _, l := range p.layers {
+		if l.LayerType() == t {
+			return l
+		}
+	}
+	return nil
+}
+func (p *eagerPacket) LayerClass(lc LayerClass) Layer {
+	for _, l := range p.layers {
+		if lc.Contains(l.LayerType()) {
+			return l
+		}
+	}
+	return nil
+}
+func (p *eagerPacket) String() string { return p.packetString() }
+func (p *eagerPacket) Dump() string   { return p.packetDump() }
+
+// lazyPacket does lazy decoding on its packet data.  On construction it does
+// no initial decoding.  For each function call, it decodes only as many layers
+// as are necessary to compute the return value for that function.
+// lazyPacket implements Packet and PacketBuilder.
+type lazyPacket struct {
+	packet
+	next Decoder
+}
+
+func (p *lazyPacket) NextDecoder(next Decoder) error {
+	if next == nil {
+		return errNilDecoder
+	}
+	p.next = next
+	return nil
+}
+func (p *lazyPacket) decodeNextLayer() {
+	if p.next == nil {
+		return
+	}
+	d := p.data
+	if p.last != nil {
+		d = p.last.LayerPayload()
+	}
+	next := p.next
+	p.next = nil
+	// We've just set p.next to nil, so if we see we have no data, this should be
+	// the final call we get to decodeNextLayer if we return here.
+	if len(d) == 0 {
+		return
+	}
+	defer p.recoverDecodeError()
+	err := next.Decode(d, p)
+	if err != nil {
+		p.addFinalDecodeError(err, nil)
+	}
+}
+func (p *lazyPacket) LinkLayer() LinkLayer {
+	for p.link == nil && p.next != nil {
+		p.decodeNextLayer()
+	}
+	return p.link
+}
+func (p *lazyPacket) NetworkLayer() NetworkLayer {
+	for p.network == nil && p.next != nil {
+		p.decodeNextLayer()
+	}
+	return p.network
+}
+func (p *lazyPacket) TransportLayer() TransportLayer {
+	for p.transport == nil && p.next != nil {
+		p.decodeNextLayer()
+	}
+	return p.transport
+}
+func (p *lazyPacket) ApplicationLayer() ApplicationLayer {
+	for p.application == nil && p.next != nil {
+		p.decodeNextLayer()
+	}
+	return p.application
+}
+func (p *lazyPacket) ErrorLayer() ErrorLayer {
+	for p.failure == nil && p.next != nil {
+		p.decodeNextLayer()
+	}
+	return p.failure
+}
+func (p *lazyPacket) Layers() []Layer {
+	for p.next != nil {
+		p.decodeNextLayer()
+	}
+	return p.layers
+}
+func (p *lazyPacket) Layer(t LayerType) Layer {
+	for _, l := range p.layers {
+		if l.LayerType() == t {
+			return l
+		}
+	}
+	numLayers := len(p.layers)
+	for p.next != nil {
+		p.decodeNextLayer()
+		for _, l := range p.layers[numLayers:] {
+			if l.LayerType() == t {
+				return l
+			}
+		}
+		numLayers = len(p.layers)
+	}
+	return nil
+}
+func (p *lazyPacket) LayerClass(lc LayerClass) Layer {
+	for _, l := range p.layers {
+		if lc.Contains(l.LayerType()) {
+			return l
+		}
+	}
+	numLayers := len(p.layers)
+	for p.next != nil {
+		p.decodeNextLayer()
+		for _, l := range p.layers[numLayers:] {
+			if lc.Contains(l.LayerType()) {
+				return l
+			}
+		}
+		numLayers = len(p.layers)
+	}
+	return nil
+}
+func (p *lazyPacket) String() string { p.Layers(); return p.packetString() }
+func (p *lazyPacket) Dump() string   { p.Layers(); return p.packetDump() }
+
+// DecodeOptions tells gopacket how to decode a packet.
+type DecodeOptions struct {
+	// Lazy decoding decodes the minimum number of layers needed to return data
+	// for a packet at each function call.  Be careful using this with concurrent
+	// packet processors, as each call to packet.* could mutate the packet, and
+	// two concurrent function calls could interact poorly.
+	Lazy bool
+	// NoCopy decoding doesn't copy its input buffer into storage that's owned by
+	// the packet.  If you can guarantee that the bytes underlying the slice
+	// passed into NewPacket aren't going to be modified, this can be faster.  If
+	// there's any chance that those bytes WILL be changed, this will invalidate
+	// your packets.
+	NoCopy bool
+	// SkipDecodeRecovery skips over panic recovery during packet decoding.
+	// Normally, when packets decode, if a panic occurs, that panic is captured
+	// by a recover(), and a DecodeFailure layer is added to the packet detailing
+	// the issue.  If this flag is set, panics are instead allowed to continue up
+	// the stack.
+	SkipDecodeRecovery bool
+	// DecodeStreamsAsDatagrams enables routing of application-level layers in the TCP
+	// decoder. If true, we should try to decode layers after TCP in single packets.
+	// This is disabled by default because the reassembly package drives the decoding
+	// of TCP payload data after reassembly.
+	DecodeStreamsAsDatagrams bool
+}
+
+// Default decoding provides the safest (but slowest) method for decoding
+// packets.  It eagerly processes all layers (so it's concurrency-safe) and it
+// copies its input buffer upon creation of the packet (so the packet remains
+// valid if the underlying slice is modified.  Both of these take time,
+// though, so beware.  If you can guarantee that the packet will only be used
+// by one goroutine at a time, set Lazy decoding.  If you can guarantee that
+// the underlying slice won't change, set NoCopy decoding.
+var Default = DecodeOptions{}
+
+// Lazy is a DecodeOptions with just Lazy set.
+var Lazy = DecodeOptions{Lazy: true}
+
+// NoCopy is a DecodeOptions with just NoCopy set.
+var NoCopy = DecodeOptions{NoCopy: true}
+
+// DecodeStreamsAsDatagrams is a DecodeOptions with just DecodeStreamsAsDatagrams set.
+var DecodeStreamsAsDatagrams = DecodeOptions{DecodeStreamsAsDatagrams: true}
+
+// NewPacket creates a new Packet object from a set of bytes.  The
+// firstLayerDecoder tells it how to interpret the first layer from the bytes,
+// future layers will be generated from that first layer automatically.
+func NewPacket(data []byte, firstLayerDecoder Decoder, options DecodeOptions) Packet {
+	if !options.NoCopy {
+		dataCopy := make([]byte, len(data))
+		copy(dataCopy, data)
+		data = dataCopy
+	}
+	if options.Lazy {
+		p := &lazyPacket{
+			packet: packet{data: data, decodeOptions: options},
+			next:   firstLayerDecoder,
+		}
+		p.layers = p.initialLayers[:0]
+		// Crazy craziness:
+		// If the following return statemet is REMOVED, and Lazy is FALSE, then
+		// eager packet processing becomes 17% FASTER.  No, there is no logical
+		// explanation for this.  However, it's such a hacky micro-optimization that
+		// we really can't rely on it.  It appears to have to do with the size the
+		// compiler guesses for this function's stack space, since one symptom is
+		// that with the return statement in place, we more than double calls to
+		// runtime.morestack/runtime.lessstack.  We'll hope the compiler gets better
+		// over time and we get this optimization for free.  Until then, we'll have
+		// to live with slower packet processing.
+		return p
+	}
+	p := &eagerPacket{
+		packet: packet{data: data, decodeOptions: options},
+	}
+	p.layers = p.initialLayers[:0]
+	p.initialDecode(firstLayerDecoder)
+	return p
+}
+
+// PacketDataSource is an interface for some source of packet data.  Users may
+// create their own implementations, or use the existing implementations in
+// gopacket/pcap (libpcap, allows reading from live interfaces or from
+// pcap files) or gopacket/pfring (PF_RING, allows reading from live
+// interfaces).
+type PacketDataSource interface {
+	// ReadPacketData returns the next packet available from this data source.
+	// It returns:
+	//  data:  The bytes of an individual packet.
+	//  ci:  Metadata about the capture
+	//  err:  An error encountered while reading packet data.  If err != nil,
+	//    then data/ci will be ignored.
+	ReadPacketData() (data []byte, ci CaptureInfo, err error)
+}
+
+// ConcatFinitePacketDataSources returns a PacketDataSource that wraps a set
+// of internal PacketDataSources, each of which will stop with io.EOF after
+// reading a finite number of packets.  The returned PacketDataSource will
+// return all packets from the first finite source, followed by all packets from
+// the second, etc.  Once all finite sources have returned io.EOF, the returned
+// source will as well.
+func ConcatFinitePacketDataSources(pds ...PacketDataSource) PacketDataSource {
+	c := concat(pds)
+	return &c
+}
+
+type concat []PacketDataSource
+
+func (c *concat) ReadPacketData() (data []byte, ci CaptureInfo, err error) {
+	for len(*c) > 0 {
+		data, ci, err = (*c)[0].ReadPacketData()
+		if err == io.EOF {
+			*c = (*c)[1:]
+			continue
+		}
+		return
+	}
+	return nil, CaptureInfo{}, io.EOF
+}
+
+// ZeroCopyPacketDataSource is an interface to pull packet data from sources
+// that allow data to be returned without copying to a user-controlled buffer.
+// It's very similar to PacketDataSource, except that the caller must be more
+// careful in how the returned buffer is handled.
+type ZeroCopyPacketDataSource interface {
+	// ZeroCopyReadPacketData returns the next packet available from this data source.
+	// It returns:
+	//  data:  The bytes of an individual packet.  Unlike with
+	//    PacketDataSource's ReadPacketData, the slice returned here points
+	//    to a buffer owned by the data source.  In particular, the bytes in
+	//    this buffer may be changed by future calls to
+	//    ZeroCopyReadPacketData.  Do not use the returned buffer after
+	//    subsequent ZeroCopyReadPacketData calls.
+	//  ci:  Metadata about the capture
+	//  err:  An error encountered while reading packet data.  If err != nil,
+	//    then data/ci will be ignored.
+	ZeroCopyReadPacketData() (data []byte, ci CaptureInfo, err error)
+}
+
+// PacketSource reads in packets from a PacketDataSource, decodes them, and
+// returns them.
+//
+// There are currently two different methods for reading packets in through
+// a PacketSource:
+//
+// Reading With Packets Function
+//
+// This method is the most convenient and easiest to code, but lacks
+// flexibility.  Packets returns a 'chan Packet', then asynchronously writes
+// packets into that channel.  Packets uses a blocking channel, and closes
+// it if an io.EOF is returned by the underlying PacketDataSource.  All other
+// PacketDataSource errors are ignored and discarded.
+//  for packet := range packetSource.Packets() {
+//    ...
+//  }
+//
+// Reading With NextPacket Function
+//
+// This method is the most flexible, and exposes errors that may be
+// encountered by the underlying PacketDataSource.  It's also the fastest
+// in a tight loop, since it doesn't have the overhead of a channel
+// read/write.  However, it requires the user to handle errors, most
+// importantly the io.EOF error in cases where packets are being read from
+// a file.
+//  for {
+//    packet, err := packetSource.NextPacket()
+//    if err == io.EOF {
+//      break
+//    } else if err != nil {
+//      log.Println("Error:", err)
+//      continue
+//    }
+//    handlePacket(packet)  // Do something with each packet.
+//  }
+type PacketSource struct {
+	source  PacketDataSource
+	decoder Decoder
+	// DecodeOptions is the set of options to use for decoding each piece
+	// of packet data.  This can/should be changed by the user to reflect the
+	// way packets should be decoded.
+	DecodeOptions
+	c chan Packet
+}
+
+// NewPacketSource creates a packet data source.
+func NewPacketSource(source PacketDataSource, decoder Decoder) *PacketSource {
+	return &PacketSource{
+		source:  source,
+		decoder: decoder,
+	}
+}
+
+// NextPacket returns the next decoded packet from the PacketSource.  On error,
+// it returns a nil packet and a non-nil error.
+func (p *PacketSource) NextPacket() (Packet, error) {
+	data, ci, err := p.source.ReadPacketData()
+	if err != nil {
+		return nil, err
+	}
+	packet := NewPacket(data, p.decoder, p.DecodeOptions)
+	m := packet.Metadata()
+	m.CaptureInfo = ci
+	m.Truncated = m.Truncated || ci.CaptureLength < ci.Length
+	return packet, nil
+}
+
+// packetsToChannel reads in all packets from the packet source and sends them
+// to the given channel. This routine terminates when a non-temporary error
+// is returned by NextPacket().
+func (p *PacketSource) packetsToChannel() {
+	defer close(p.c)
+	for {
+		packet, err := p.NextPacket()
+		if err == nil {
+			p.c <- packet
+			continue
+		}
+
+		// Immediately retry for temporary network errors
+		if nerr, ok := err.(net.Error); ok && nerr.Temporary() {
+			continue
+		}
+
+		// Immediately retry for EAGAIN
+		if err == syscall.EAGAIN {
+			continue
+		}
+
+		// Immediately break for known unrecoverable errors
+		if err == io.EOF || err == io.ErrUnexpectedEOF ||
+			err == io.ErrNoProgress || err == io.ErrClosedPipe || err == io.ErrShortBuffer ||
+			err == syscall.EBADF ||
+			strings.Contains(err.Error(), "use of closed file") {
+			break
+		}
+
+		// Sleep briefly and try again
+		time.Sleep(time.Millisecond * time.Duration(5))
+	}
+}
+
+// Packets returns a channel of packets, allowing easy iterating over
+// packets.  Packets will be asynchronously read in from the underlying
+// PacketDataSource and written to the returned channel.  If the underlying
+// PacketDataSource returns an io.EOF error, the channel will be closed.
+// If any other error is encountered, it is ignored.
+//
+//  for packet := range packetSource.Packets() {
+//    handlePacket(packet)  // Do something with each packet.
+//  }
+//
+// If called more than once, returns the same channel.
+func (p *PacketSource) Packets() chan Packet {
+	if p.c == nil {
+		p.c = make(chan Packet, 1000)
+		go p.packetsToChannel()
+	}
+	return p.c
+}