vendor: add packages

vendor/github.com/pires/go-proxyproto/.gitignore

@@ -0,0 +1,9 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+.idea
+bin
+pkg

vendor/github.com/pires/go-proxyproto/.travis.yml

@@ -0,0 +1,15 @@
+language: go
+sudo: false
+go:
+  - 1.11
+install:
+  - go get golang.org/x/tools/cmd/cover
+  - go get github.com/mattn/goveralls
+script:
+  - go fmt
+  - go vet
+  - go test -v -covermode=count -coverprofile=coverage.out
+  - $HOME/gopath/bin/goveralls -coverprofile=coverage.out -service=travis-ci -repotoken $COVERALLS_TOKEN
+env:
+  global:
+    secure: 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

vendor/github.com/pires/go-proxyproto/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
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+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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+      whether in tort (including negligence), contract, or otherwise,
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+      negligent acts) or agreed to in writing, shall any Contributor be
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+      of your accepting any such warranty or additional liability.
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+       http://www.apache.org/licenses/LICENSE-2.0
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+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/pires/go-proxyproto/README.md

@@ -0,0 +1,32 @@
+# go-proxyproto
+
+[![Build Status](https://travis-ci.org/pires/go-proxyproto.svg?branch=master)](https://travis-ci.org/pires/go-proxyproto)
+[![Coverage Status](https://coveralls.io/repos/github/pires/go-proxyproto/badge.svg?branch=master)](https://coveralls.io/github/pires/go-proxyproto?branch=master)
+[![Go Report Card](https://goreportcard.com/badge/github.com/pires/go-proxyproto)](https://goreportcard.com/report/github.com/pires/go-proxyproto)
+
+A Go library implementation of the [PROXY protocol, versions 1 and 2](http://www.haproxy.org/download/1.5/doc/proxy-protocol.txt),
+which provides, as per specification:
+> (...) a convenient way to safely transport connection
+> information such as a client's address across multiple layers of NAT or TCP
+> proxies. It is designed to require little changes to existing components and
+> to limit the performance impact caused by the processing of the transported
+> information.
+
+This library is to be used in one of or both proxy clients and proxy servers that need to support said protocol.
+Both protocol versions, 1 (text-based) and 2 (binary-based) are supported.
+
+## Installation
+
+```shell
+$ go get -u github.com/pires/go-proxyproto
+```
+
+## Usage
+
+### Client (TODO)
+
+### Server (TODO)
+
+## Documentation
+
+[http://godoc.org/github.com/pires/go-proxyproto](http://godoc.org/github.com/pires/go-proxyproto)

vendor/github.com/pires/go-proxyproto/addr_proto.go

@@ -0,0 +1,71 @@
+package proxyproto
+
+// AddressFamilyAndProtocol represents address family and transport protocol.
+type AddressFamilyAndProtocol byte
+
+const (
+	UNSPEC       = '\x00'
+	TCPv4        = '\x11'
+	UDPv4        = '\x12'
+	TCPv6        = '\x21'
+	UDPv6        = '\x22'
+	UnixStream   = '\x31'
+	UnixDatagram = '\x32'
+)
+
+var supportedTransportProtocol = map[AddressFamilyAndProtocol]bool{
+	TCPv4:        true,
+	UDPv4:        true,
+	TCPv6:        true,
+	UDPv6:        true,
+	UnixStream:   true,
+	UnixDatagram: true,
+}
+
+// IsIPv4 returns true if the address family is IPv4 (AF_INET4), false otherwise.
+func (ap AddressFamilyAndProtocol) IsIPv4() bool {
+	return 0x10 == ap&0xF0
+}
+
+// IsIPv6 returns true if the address family is IPv6 (AF_INET6), false otherwise.
+func (ap AddressFamilyAndProtocol) IsIPv6() bool {
+	return 0x20 == ap&0xF0
+}
+
+// IsUnix returns true if the address family is UNIX (AF_UNIX), false otherwise.
+func (ap AddressFamilyAndProtocol) IsUnix() bool {
+	return 0x30 == ap&0xF0
+}
+
+// IsStream returns true if the transport protocol is TCP or STREAM (SOCK_STREAM), false otherwise.
+func (ap AddressFamilyAndProtocol) IsStream() bool {
+	return 0x01 == ap&0x0F
+}
+
+// IsDatagram returns true if the transport protocol is UDP or DGRAM (SOCK_DGRAM), false otherwise.
+func (ap AddressFamilyAndProtocol) IsDatagram() bool {
+	return 0x02 == ap&0x0F
+}
+
+// IsUnspec returns true if the transport protocol or address family is unspecified, false otherwise.
+func (ap AddressFamilyAndProtocol) IsUnspec() bool {
+	return (0x00 == ap&0xF0) || (0x00 == ap&0x0F)
+}
+
+func (ap AddressFamilyAndProtocol) toByte() byte {
+	if ap.IsIPv4() && ap.IsStream() {
+		return TCPv4
+	} else if ap.IsIPv4() && ap.IsDatagram() {
+		return UDPv4
+	} else if ap.IsIPv6() && ap.IsStream() {
+		return TCPv6
+	} else if ap.IsIPv6() && ap.IsDatagram() {
+		return UDPv6
+	} else if ap.IsUnix() && ap.IsStream() {
+		return UnixStream
+	} else if ap.IsUnix() && ap.IsDatagram() {
+		return UnixDatagram
+	}
+
+	return UNSPEC
+}

vendor/github.com/pires/go-proxyproto/header.go

@@ -0,0 +1,116 @@
+// Package proxyproto implements Proxy Protocol (v1 and v2) parser and writer, as per specification:
+// http://www.haproxy.org/download/1.5/doc/proxy-protocol.txt
+package proxyproto
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"io"
+	"net"
+	"time"
+)
+
+var (
+	// Protocol
+	SIGV1 = []byte{'\x50', '\x52', '\x4F', '\x58', '\x59'}
+	SIGV2 = []byte{'\x0D', '\x0A', '\x0D', '\x0A', '\x00', '\x0D', '\x0A', '\x51', '\x55', '\x49', '\x54', '\x0A'}
+
+	ErrCantReadProtocolVersionAndCommand    = errors.New("Can't read proxy protocol version and command")
+	ErrCantReadAddressFamilyAndProtocol     = errors.New("Can't read address family or protocol")
+	ErrCantReadLength                       = errors.New("Can't read length")
+	ErrCantResolveSourceUnixAddress         = errors.New("Can't resolve source Unix address")
+	ErrCantResolveDestinationUnixAddress    = errors.New("Can't resolve destination Unix address")
+	ErrNoProxyProtocol                      = errors.New("Proxy protocol signature not present")
+	ErrUnknownProxyProtocolVersion          = errors.New("Unknown proxy protocol version")
+	ErrUnsupportedProtocolVersionAndCommand = errors.New("Unsupported proxy protocol version and command")
+	ErrUnsupportedAddressFamilyAndProtocol  = errors.New("Unsupported address family and protocol")
+	ErrInvalidLength                        = errors.New("Invalid length")
+	ErrInvalidAddress                       = errors.New("Invalid address")
+	ErrInvalidPortNumber                    = errors.New("Invalid port number")
+)
+
+// Header is the placeholder for proxy protocol header.
+type Header struct {
+	Version            byte
+	Command            ProtocolVersionAndCommand
+	TransportProtocol  AddressFamilyAndProtocol
+	SourceAddress      net.IP
+	DestinationAddress net.IP
+	SourcePort         uint16
+	DestinationPort    uint16
+}
+
+// EqualTo returns true if headers are equivalent, false otherwise.
+func (header *Header) EqualTo(q *Header) bool {
+	if header == nil || q == nil {
+		return false
+	}
+	if header.Command.IsLocal() {
+		return true
+	}
+	return header.TransportProtocol == q.TransportProtocol &&
+		header.SourceAddress.String() == q.SourceAddress.String() &&
+		header.DestinationAddress.String() == q.DestinationAddress.String() &&
+		header.SourcePort == q.SourcePort &&
+		header.DestinationPort == q.DestinationPort
+}
+
+// WriteTo renders a proxy protocol header in a format to write over the wire.
+func (header *Header) WriteTo(w io.Writer) (int64, error) {
+	switch header.Version {
+	case 1:
+		return header.writeVersion1(w)
+	case 2:
+		return header.writeVersion2(w)
+	default:
+		return 0, ErrUnknownProxyProtocolVersion
+	}
+}
+
+// Read identifies the proxy protocol version and reads the remaining of
+// the header, accordingly.
+//
+// If proxy protocol header signature is not present, the reader buffer remains untouched
+// and is safe for reading outside of this code.
+//
+// If proxy protocol header signature is present but an error is raised while processing
+// the remaining header, assume the reader buffer to be in a corrupt state.
+// Also, this operation will block until enough bytes are available for peeking.
+func Read(reader *bufio.Reader) (*Header, error) {
+	// In order to improve speed for small non-PROXYed packets, take a peek at the first byte alone.
+	if b1, err := reader.Peek(1); err == nil && (bytes.Equal(b1[:1], SIGV1[:1]) || bytes.Equal(b1[:1], SIGV2[:1])) {
+		if signature, err := reader.Peek(5); err == nil && bytes.Equal(signature[:5], SIGV1) {
+			return parseVersion1(reader)
+		} else if signature, err := reader.Peek(12); err == nil && bytes.Equal(signature[:12], SIGV2) {
+			return parseVersion2(reader)
+		}
+	}
+
+	return nil, ErrNoProxyProtocol
+}
+
+// ReadTimeout acts as Read but takes a timeout. If that timeout is reached, it's assumed
+// there's no proxy protocol header.
+func ReadTimeout(reader *bufio.Reader, timeout time.Duration) (*Header, error) {
+	type header struct {
+		h *Header
+		e error
+	}
+	read := make(chan *header, 1)
+
+	go func() {
+		h := &header{}
+		h.h, h.e = Read(reader)
+		read <- h
+	}()
+
+	timer := time.NewTimer(timeout)
+	select {
+	case result := <-read:
+		timer.Stop()
+		return result.h, result.e
+	case <-timer.C:
+		return nil, ErrNoProxyProtocol
+	}
+}

vendor/github.com/pires/go-proxyproto/v1.go

@@ -0,0 +1,116 @@
+package proxyproto
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+	"net"
+	"strconv"
+	"strings"
+)
+
+const (
+	CRLF      = "\r\n"
+	SEPARATOR = " "
+)
+
+func initVersion1() *Header {
+	header := new(Header)
+	header.Version = 1
+	// Command doesn't exist in v1
+	header.Command = PROXY
+	return header
+}
+
+func parseVersion1(reader *bufio.Reader) (*Header, error) {
+	// Make sure we have a v1 header
+	line, err := reader.ReadString('\n')
+	if !strings.HasSuffix(line, CRLF) {
+		return nil, ErrCantReadProtocolVersionAndCommand
+	}
+	tokens := strings.Split(line[:len(line)-2], SEPARATOR)
+	if len(tokens) < 6 {
+		return nil, ErrCantReadProtocolVersionAndCommand
+	}
+
+	header := initVersion1()
+
+	// Read address family and protocol
+	switch tokens[1] {
+	case "TCP4":
+		header.TransportProtocol = TCPv4
+	case "TCP6":
+		header.TransportProtocol = TCPv6
+	default:
+		header.TransportProtocol = UNSPEC
+	}
+
+	// Read addresses and ports
+	header.SourceAddress, err = parseV1IPAddress(header.TransportProtocol, tokens[2])
+	if err != nil {
+		return nil, err
+	}
+	header.DestinationAddress, err = parseV1IPAddress(header.TransportProtocol, tokens[3])
+	if err != nil {
+		return nil, err
+	}
+	header.SourcePort, err = parseV1PortNumber(tokens[4])
+	if err != nil {
+		return nil, err
+	}
+	header.DestinationPort, err = parseV1PortNumber(tokens[5])
+	if err != nil {
+		return nil, err
+	}
+	return header, nil
+}
+
+func (header *Header) writeVersion1(w io.Writer) (int64, error) {
+	// As of version 1, only "TCP4" ( \x54 \x43 \x50 \x34 ) for TCP over IPv4,
+	// and "TCP6" ( \x54 \x43 \x50 \x36 ) for TCP over IPv6 are allowed.
+	proto := "UNKNOWN"
+	if header.TransportProtocol == TCPv4 {
+		proto = "TCP4"
+	} else if header.TransportProtocol == TCPv6 {
+		proto = "TCP6"
+	}
+
+	var buf bytes.Buffer
+	buf.Write(SIGV1)
+	buf.WriteString(SEPARATOR)
+	buf.WriteString(proto)
+	buf.WriteString(SEPARATOR)
+	buf.WriteString(header.SourceAddress.String())
+	buf.WriteString(SEPARATOR)
+	buf.WriteString(header.DestinationAddress.String())
+	buf.WriteString(SEPARATOR)
+	buf.WriteString(strconv.Itoa(int(header.SourcePort)))
+	buf.WriteString(SEPARATOR)
+	buf.WriteString(strconv.Itoa(int(header.DestinationPort)))
+	buf.WriteString(CRLF)
+
+	return buf.WriteTo(w)
+}
+
+func parseV1PortNumber(portStr string) (uint16, error) {
+	var port uint16
+
+	_port, err := strconv.Atoi(portStr)
+	if err == nil {
+		if port < 0 || port > 65535 {
+			err = ErrInvalidPortNumber
+		}
+		port = uint16(_port)
+	}
+
+	return port, err
+}
+
+func parseV1IPAddress(protocol AddressFamilyAndProtocol, addrStr string) (addr net.IP, err error) {
+	addr = net.ParseIP(addrStr)
+	tryV4 := addr.To4()
+	if (protocol == TCPv4 && tryV4 == nil) || (protocol == TCPv6 && tryV4 != nil) {
+		err = ErrInvalidAddress
+	}
+	return
+}

vendor/github.com/pires/go-proxyproto/v2.go

@@ -0,0 +1,202 @@
+package proxyproto
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/binary"
+	"io"
+)
+
+var (
+	lengthV4   = uint16(12)
+	lengthV6   = uint16(36)
+	lengthUnix = uint16(218)
+
+	lengthV4Bytes = func() []byte {
+		a := make([]byte, 2)
+		binary.BigEndian.PutUint16(a, lengthV4)
+		return a
+	}()
+	lengthV6Bytes = func() []byte {
+		a := make([]byte, 2)
+		binary.BigEndian.PutUint16(a, lengthV6)
+		return a
+	}()
+	lengthUnixBytes = func() []byte {
+		a := make([]byte, 2)
+		binary.BigEndian.PutUint16(a, lengthUnix)
+		return a
+	}()
+)
+
+type _ports struct {
+	SrcPort uint16
+	DstPort uint16
+}
+
+type _addr4 struct {
+	Src     [4]byte
+	Dst     [4]byte
+	SrcPort uint16
+	DstPort uint16
+}
+
+type _addr6 struct {
+	Src [16]byte
+	Dst [16]byte
+	_ports
+}
+
+type _addrUnix struct {
+	Src [108]byte
+	Dst [108]byte
+}
+
+func parseVersion2(reader *bufio.Reader) (header *Header, err error) {
+	// Skip first 12 bytes (signature)
+	for i := 0; i < 12; i++ {
+		if _, err = reader.ReadByte(); err != nil {
+			return nil, ErrCantReadProtocolVersionAndCommand
+		}
+	}
+
+	header = new(Header)
+	header.Version = 2
+
+	// Read the 13th byte, protocol version and command
+	b13, err := reader.ReadByte()
+	if err != nil {
+		return nil, ErrCantReadProtocolVersionAndCommand
+	}
+	header.Command = ProtocolVersionAndCommand(b13)
+	if _, ok := supportedCommand[header.Command]; !ok {
+		return nil, ErrUnsupportedProtocolVersionAndCommand
+	}
+	// If command is LOCAL, header ends here
+	if header.Command.IsLocal() {
+		return header, nil
+	}
+
+	// Read the 14th byte, address family and protocol
+	b14, err := reader.ReadByte()
+	if err != nil {
+		return nil, ErrCantReadAddressFamilyAndProtocol
+	}
+	header.TransportProtocol = AddressFamilyAndProtocol(b14)
+	if _, ok := supportedTransportProtocol[header.TransportProtocol]; !ok {
+		return nil, ErrUnsupportedAddressFamilyAndProtocol
+	}
+
+	// Make sure there are bytes available as specified in length
+	var length uint16
+	if err := binary.Read(io.LimitReader(reader, 2), binary.BigEndian, &length); err != nil {
+		return nil, ErrCantReadLength
+	}
+	if !header.validateLength(length) {
+		return nil, ErrInvalidLength
+	}
+
+	if _, err := reader.Peek(int(length)); err != nil {
+		return nil, ErrInvalidLength
+	}
+
+	// Length-limited reader for payload section
+	payloadReader := io.LimitReader(reader, int64(length))
+
+	// Read addresses and ports
+	if header.TransportProtocol.IsIPv4() {
+		var addr _addr4
+		if err := binary.Read(payloadReader, binary.BigEndian, &addr); err != nil {
+			return nil, ErrInvalidAddress
+		}
+		header.SourceAddress = addr.Src[:]
+		header.DestinationAddress = addr.Dst[:]
+		header.SourcePort = addr.SrcPort
+		header.DestinationPort = addr.DstPort
+	} else if header.TransportProtocol.IsIPv6() {
+		var addr _addr6
+		if err := binary.Read(payloadReader, binary.BigEndian, &addr); err != nil {
+			return nil, ErrInvalidAddress
+		}
+		header.SourceAddress = addr.Src[:]
+		header.DestinationAddress = addr.Dst[:]
+		header.SourcePort = addr.SrcPort
+		header.DestinationPort = addr.DstPort
+	}
+	// TODO fully support Unix addresses
+	//	else if header.TransportProtocol.IsUnix() {
+	//		var addr _addrUnix
+	//		if err := binary.Read(payloadReader, binary.BigEndian, &addr); err != nil {
+	//			return nil, ErrInvalidAddress
+	//		}
+	//
+	//if header.SourceAddress, err = net.ResolveUnixAddr("unix", string(addr.Src[:])); err != nil {
+	//	return nil, ErrCantResolveSourceUnixAddress
+	//}
+	//if header.DestinationAddress, err = net.ResolveUnixAddr("unix", string(addr.Dst[:])); err != nil {
+	//	return nil, ErrCantResolveDestinationUnixAddress
+	//}
+	//}
+
+	// TODO add encapsulated TLV support
+
+	// Drain the remaining padding
+	payloadReader.Read(make([]byte, length))
+
+	return header, nil
+}
+
+func (header *Header) writeVersion2(w io.Writer) (int64, error) {
+	var buf bytes.Buffer
+	buf.Write(SIGV2)
+	buf.WriteByte(header.Command.toByte())
+	if !header.Command.IsLocal() {
+		buf.WriteByte(header.TransportProtocol.toByte())
+		// TODO add encapsulated TLV length
+		var addrSrc, addrDst []byte
+		if header.TransportProtocol.IsIPv4() {
+			buf.Write(lengthV4Bytes)
+			addrSrc = header.SourceAddress.To4()
+			addrDst = header.DestinationAddress.To4()
+		} else if header.TransportProtocol.IsIPv6() {
+			buf.Write(lengthV6Bytes)
+			addrSrc = header.SourceAddress.To16()
+			addrDst = header.DestinationAddress.To16()
+		} else if header.TransportProtocol.IsUnix() {
+			buf.Write(lengthUnixBytes)
+			// TODO is below right?
+			addrSrc = []byte(header.SourceAddress.String())
+			addrDst = []byte(header.DestinationAddress.String())
+		}
+		buf.Write(addrSrc)
+		buf.Write(addrDst)
+
+		portSrcBytes := func() []byte {
+			a := make([]byte, 2)
+			binary.BigEndian.PutUint16(a, header.SourcePort)
+			return a
+		}()
+		buf.Write(portSrcBytes)
+
+		portDstBytes := func() []byte {
+			a := make([]byte, 2)
+			binary.BigEndian.PutUint16(a, header.DestinationPort)
+			return a
+		}()
+		buf.Write(portDstBytes)
+
+	}
+
+	return buf.WriteTo(w)
+}
+
+func (header *Header) validateLength(length uint16) bool {
+	if header.TransportProtocol.IsIPv4() {
+		return length >= lengthV4
+	} else if header.TransportProtocol.IsIPv6() {
+		return length >= lengthV6
+	} else if header.TransportProtocol.IsUnix() {
+		return length >= lengthUnix
+	}
+	return false
+}

vendor/github.com/pires/go-proxyproto/version_cmd.go

@@ -0,0 +1,39 @@
+package proxyproto
+
+// ProtocolVersionAndCommand represents proxy protocol version and command.
+type ProtocolVersionAndCommand byte
+
+const (
+	LOCAL = '\x20'
+	PROXY = '\x21'
+)
+
+var supportedCommand = map[ProtocolVersionAndCommand]bool{
+	LOCAL: true,
+	PROXY: true,
+}
+
+// IsLocal returns true if the protocol version is \x2 and command is LOCAL, false otherwise.
+func (pvc ProtocolVersionAndCommand) IsLocal() bool {
+	return 0x20 == pvc&0xF0 && 0x00 == pvc&0x0F
+}
+
+// IsProxy returns true if the protocol version is \x2 and command is PROXY, false otherwise.
+func (pvc ProtocolVersionAndCommand) IsProxy() bool {
+	return 0x20 == pvc&0xF0 && 0x01 == pvc&0x0F
+}
+
+// IsUnspec returns true if the protocol version or command is unspecified, false otherwise.
+func (pvc ProtocolVersionAndCommand) IsUnspec() bool {
+	return !(pvc.IsLocal() || pvc.IsProxy())
+}
+
+func (pvc ProtocolVersionAndCommand) toByte() byte {
+	if pvc.IsLocal() {
+		return LOCAL
+	} else if pvc.IsProxy() {
+		return PROXY
+	}
+
+	return LOCAL
+}

vendor/modules.txt

@@ -31,6 +31,8 @@ github.com/inconshreveable/mousetrap
 github.com/klauspost/cpuid
 # github.com/klauspost/reedsolomon v1.9.1
 github.com/klauspost/reedsolomon
+# github.com/pires/go-proxyproto v0.0.0-20190111085350-4d51b51e3bfc
+github.com/pires/go-proxyproto
 # github.com/pkg/errors v0.8.0
 github.com/pkg/errors
 # github.com/pmezard/go-difflib v1.0.0