Update code to use pault.ag/go/sniff package (#5038)

* Update code to use pault.ag/go/sniff package

* Update go dependencies

go.mod

@@ -3,7 +3,7 @@ module k8s.io/ingress-nginx
 go 1.13
 
 require (
-	github.com/armon/go-proxyproto v0.0.0-20190211145416-68259f75880e
+	github.com/armon/go-proxyproto v0.0.0-20200108142055-f0b8253b1507
 	github.com/eapache/channels v1.1.0
 	github.com/eapache/queue v1.1.0 // indirect
 	github.com/fullsailor/pkcs7 v0.0.0-20190404230743-d7302db945fa // indirect
@@ -11,7 +11,7 @@ require (
 	github.com/imdario/mergo v0.3.7
 	github.com/json-iterator/go v1.1.9
 	github.com/kylelemons/godebug v0.0.0-20170820004349-d65d576e9348
-	github.com/mitchellh/go-ps v0.0.0-20170309133038-4fdf99ab2936
+	github.com/mitchellh/go-ps v1.0.0
 	github.com/mitchellh/hashstructure v1.0.0
 	github.com/mitchellh/mapstructure v1.1.2
 	github.com/moul/pb v0.0.0-20180404114147-54bdd96e6a52
@@ -20,8 +20,7 @@ require (
 	github.com/onsi/gomega v1.8.1
 	github.com/opencontainers/runc v1.0.0-rc9
 	github.com/parnurzeal/gorequest v0.2.16
-	github.com/paultag/sniff v0.0.0-20200207005214-cf7e4d167732
-	github.com/pkg/errors v0.8.1
+	github.com/pkg/errors v0.9.1
 	github.com/prometheus/client_golang v1.4.0
 	github.com/prometheus/client_model v0.2.0
 	github.com/prometheus/common v0.9.1
@@ -46,7 +45,7 @@ require (
 	k8s.io/klog v1.0.0
 	k8s.io/kubernetes v1.17.2
 	moul.io/http2curl v1.0.0 // indirect
-	pault.ag/go/sniff v0.0.0-20200207005214-cf7e4d167732 // indirect
+	pault.ag/go/sniff v0.0.0-20200207005214-cf7e4d167732
 	sigs.k8s.io/controller-runtime v0.4.0
 )
 

go.sum

@@ -51,8 +51,8 @@ github.com/andreyvit/diff v0.0.0-20170406064948-c7f18ee00883/go.mod h1:rCTlJbsFo
 github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239/go.mod h1:2FmKhYUyUczH0OGQWaF5ceTx0UBShxjsH6f8oGKYe2c=
 github.com/armon/circbuf v0.0.0-20150827004946-bbbad097214e/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
-github.com/armon/go-proxyproto v0.0.0-20190211145416-68259f75880e h1:h0gP0hBU6DsA5IQduhLWGOEfIUKzJS5hhXQBSgHuF/g=
-github.com/armon/go-proxyproto v0.0.0-20190211145416-68259f75880e/go.mod h1:QmP9hvJ91BbJmGVGSbutW19IC0Q9phDCLGaomwTJbgU=
+github.com/armon/go-proxyproto v0.0.0-20200108142055-f0b8253b1507 h1:dmVRVC/MmuwC2edm/P6oWIP+9n+p9IgVgK0lq9mBQjU=
+github.com/armon/go-proxyproto v0.0.0-20200108142055-f0b8253b1507/go.mod h1:QmP9hvJ91BbJmGVGSbutW19IC0Q9phDCLGaomwTJbgU=
 github.com/asaskevich/govalidator v0.0.0-20180720115003-f9ffefc3facf/go.mod h1:lB+ZfQJz7igIIfQNfa7Ml4HSf2uFQQRzpGGRXenZAgY=
 github.com/asaskevich/govalidator v0.0.0-20190424111038-f61b66f89f4a/go.mod h1:lB+ZfQJz7igIIfQNfa7Ml4HSf2uFQQRzpGGRXenZAgY=
 github.com/auth0/go-jwt-middleware v0.0.0-20170425171159-5493cabe49f7/go.mod h1:LWMyo4iOLWXHGdBki7NIht1kHru/0wM179h+d3g8ATM=
@@ -427,6 +427,8 @@ github.com/mitchellh/go-homedir v1.0.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrk
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/go-ps v0.0.0-20170309133038-4fdf99ab2936 h1:kw1v0NlnN+GZcU8Ma8CLF2Zzgjfx95gs3/GN3vYAPpo=
 github.com/mitchellh/go-ps v0.0.0-20170309133038-4fdf99ab2936/go.mod h1:r1VsdOzOPt1ZSrGZWFoNhsAedKnEd6r9Np1+5blZCWk=
+github.com/mitchellh/go-ps v1.0.0 h1:i6ampVEEF4wQFF+bkYfwYgY+F/uYJDktmvLPf7qIgjc=
+github.com/mitchellh/go-ps v1.0.0/go.mod h1:J4lOc8z8yJs6vUwklHw2XEIiT4z4C40KtWVN3nvg8Pg=
 github.com/mitchellh/go-wordwrap v1.0.0/go.mod h1:ZXFpozHsX6DPmq2I0TCekCxypsnAUbP2oI0UX1GXzOo=
 github.com/mitchellh/hashstructure v1.0.0 h1:ZkRJX1CyOoTkar7p/mLS5TZU4nJ1Rn/F8u9dGS02Q3Y=
 github.com/mitchellh/hashstructure v1.0.0/go.mod h1:QjSHrPWS+BGUVBYkbTZWEnOh3G1DutKwClXU/ABz6AQ=
@@ -494,10 +496,6 @@ github.com/opencontainers/runtime-spec v1.0.0/go.mod h1:jwyrGlmzljRJv/Fgzds9SsS/
 github.com/opencontainers/selinux v1.3.1-0.20190929122143-5215b1806f52/go.mod h1:+BLncwf63G4dgOzykXAxcmnFlUaOlkDdmw/CqsW6pjs=
 github.com/parnurzeal/gorequest v0.2.16 h1:T/5x+/4BT+nj+3eSknXmCTnEVGSzFzPGdpqmUVVZXHQ=
 github.com/parnurzeal/gorequest v0.2.16/go.mod h1:3Kh2QUMJoqw3icWAecsyzkpY7UzRfDhbRdTjtNwNiUE=
-github.com/paultag/sniff v0.0.0-20170624152000-87325c3dddf4 h1:bOK8V55gl1AEWE9KiXSZ0fzARvVBehdmYZOTFcQ5kUo=
-github.com/paultag/sniff v0.0.0-20170624152000-87325c3dddf4/go.mod h1:J3XXNGJINXLa4yIivdUT0Ad/srv2q0pSOWbbm6El2EY=
-github.com/paultag/sniff v0.0.0-20200207005214-cf7e4d167732 h1:nkseUkzjazCNyGhkRwnJ1OiHSwMXazsJQx+Ci+oVLEM=
-github.com/paultag/sniff v0.0.0-20200207005214-cf7e4d167732/go.mod h1:J3XXNGJINXLa4yIivdUT0Ad/srv2q0pSOWbbm6El2EY=
 github.com/pborman/uuid v1.2.0/go.mod h1:X/NO0urCmaxf9VXbdlT7C2Yzkj2IKimNn4k+gtPdI/k=
 github.com/pelletier/go-toml v1.1.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
@@ -506,6 +504,7 @@ github.com/peterbourgon/diskv v2.0.1+incompatible/go.mod h1:uqqh8zWWbv1HBMNONnaR
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v0.0.0-20151028094244-d8ed2627bdf0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=

internal/ingress/controller/tcp.go

@@ -23,7 +23,7 @@ import (
 
 	"k8s.io/klog"
 
-	"github.com/paultag/sniff/parser"
+	"pault.ag/go/sniff/parser"
 )
 
 // TCPServer describes a server that works in passthrough mode.

vendor/github.com/armon/go-proxyproto/protocol.go

@@ -49,6 +49,7 @@ type Listener struct {
 	Listener           net.Listener
 	ProxyHeaderTimeout time.Duration
 	SourceCheck        SourceChecker
+	UnknownOK          bool // allow PROXY UNKNOWN
 }
 
 // Conn is used to wrap and underlying connection which
@@ -62,6 +63,7 @@ type Conn struct {
 	useConnAddr        bool
 	once               sync.Once
 	proxyHeaderTimeout time.Duration
+	unknownOK          bool
 }
 
 // Accept waits for and returns the next connection to the listener.
@@ -83,6 +85,7 @@ func (p *Listener) Accept() (net.Conn, error) {
 	}
 	newConn := NewConn(conn, p.ProxyHeaderTimeout)
 	newConn.useConnAddr = useConnAddr
+	newConn.unknownOK = p.UnknownOK
 	return newConn, nil
 }
 
@@ -119,6 +122,22 @@ func (p *Conn) Read(b []byte) (int, error) {
 	return p.bufReader.Read(b)
 }
 
+func (p *Conn) ReadFrom(r io.Reader) (int64, error) {
+	if rf, ok := p.conn.(io.ReaderFrom); ok {
+		return rf.ReadFrom(r)
+	}
+	return io.Copy(p.conn, r)
+}
+
+func (p *Conn) WriteTo(w io.Writer) (int64, error) {
+	var err error
+	p.once.Do(func() { err = p.checkPrefix() })
+	if err != nil {
+		return 0, err
+	}
+	return p.bufReader.WriteTo(w)
+}
+
 func (p *Conn) Write(b []byte) (int, error) {
 	return p.conn.Write(b)
 }
@@ -209,13 +228,20 @@ func (p *Conn) checkPrefix() error {
 
 	// Split on spaces, should be (PROXY <type> <src addr> <dst addr> <src port> <dst port>)
 	parts := strings.Split(header, " ")
-	if len(parts) != 6 {
+	if len(parts) < 2 {
 		p.conn.Close()
 		return fmt.Errorf("Invalid header line: %s", header)
 	}
 
 	// Verify the type is known
 	switch parts[1] {
+	case "UNKNOWN":
+		if !p.unknownOK || len(parts) != 2 {
+			p.conn.Close()
+			return fmt.Errorf("Invalid UNKNOWN header line: %s", header)
+		}
+		p.useConnAddr = true
+		return nil
 	case "TCP4":
 	case "TCP6":
 	default:
@@ -223,6 +249,11 @@ func (p *Conn) checkPrefix() error {
 		return fmt.Errorf("Unhandled address type: %s", parts[1])
 	}
 
+	if len(parts) != 6 {
+		p.conn.Close()
+		return fmt.Errorf("Invalid header line: %s", header)
+	}
+
 	// Parse out the source address
 	ip := net.ParseIP(parts[2])
 	if ip == nil {

vendor/github.com/mitchellh/go-ps/README.md

@@ -1,4 +1,4 @@
-# Process List Library for Go
+# Process List Library for Go [![GoDoc](https://godoc.org/github.com/mitchellh/go-ps?status.png)](https://godoc.org/github.com/mitchellh/go-ps)
 
 go-ps is a library for Go that implements OS-specific APIs to list and
 manipulate processes in a platform-safe way. The library can find and

vendor/github.com/mitchellh/go-ps/go.mod

@@ -0,0 +1,3 @@
+module github.com/mitchellh/go-ps
+
+go 1.13

vendor/github.com/mitchellh/go-ps/process_freebsd.go

@@ -1,4 +1,4 @@
-// +build freebsd,amd64
+// +build freebsd
 
 package ps
 

vendor/github.com/mitchellh/go-ps/process_unix.go

@@ -56,7 +56,7 @@ func processes() ([]Process, error) {
 
 	results := make([]Process, 0, 50)
 	for {
-		fis, err := d.Readdir(10)
+		names, err := d.Readdirnames(10)
 		if err == io.EOF {
 			break
 		}
@@ -64,14 +64,8 @@ func processes() ([]Process, error) {
 			return nil, err
 		}
 
-		for _, fi := range fis {
-			// We only care about directories, since all pids are dirs
-			if !fi.IsDir() {
-				continue
-			}
-
+		for _, name := range names {
 			// We only care if the name starts with a numeric
-			name := fi.Name()
 			if name[0] < '0' || name[0] > '9' {
 				continue
 			}

vendor/github.com/pkg/errors/.travis.yml

@@ -1,15 +1,10 @@
 language: go
 go_import_path: github.com/pkg/errors
 go:
-  - 1.4.x
-  - 1.5.x
-  - 1.6.x
-  - 1.7.x
-  - 1.8.x
-  - 1.9.x
-  - 1.10.x
   - 1.11.x
+  - 1.12.x
+  - 1.13.x
   - tip
 
 script:
-  - go test -v ./...
+  - make check

vendor/github.com/pkg/errors/Makefile

@@ -0,0 +1,44 @@
+PKGS := github.com/pkg/errors
+SRCDIRS := $(shell go list -f '{{.Dir}}' $(PKGS))
+GO := go
+
+check: test vet gofmt misspell unconvert staticcheck ineffassign unparam
+
+test: 
+	$(GO) test $(PKGS)
+
+vet: | test
+	$(GO) vet $(PKGS)
+
+staticcheck:
+	$(GO) get honnef.co/go/tools/cmd/staticcheck
+	staticcheck -checks all $(PKGS)
+
+misspell:
+	$(GO) get github.com/client9/misspell/cmd/misspell
+	misspell \
+		-locale GB \
+		-error \
+		*.md *.go
+
+unconvert:
+	$(GO) get github.com/mdempsky/unconvert
+	unconvert -v $(PKGS)
+
+ineffassign:
+	$(GO) get github.com/gordonklaus/ineffassign
+	find $(SRCDIRS) -name '*.go' | xargs ineffassign
+
+pedantic: check errcheck
+
+unparam:
+	$(GO) get mvdan.cc/unparam
+	unparam ./...
+
+errcheck:
+	$(GO) get github.com/kisielk/errcheck
+	errcheck $(PKGS)
+
+gofmt:  
+	@echo Checking code is gofmted
+	@test -z "$(shell gofmt -s -l -d -e $(SRCDIRS) | tee /dev/stderr)"

vendor/github.com/pkg/errors/README.md

@@ -41,11 +41,18 @@ default:
 
 [Read the package documentation for more information](https://godoc.org/github.com/pkg/errors).
 
+## Roadmap
+
+With the upcoming [Go2 error proposals](https://go.googlesource.com/proposal/+/master/design/go2draft.md) this package is moving into maintenance mode. The roadmap for a 1.0 release is as follows:
+
+- 0.9. Remove pre Go 1.9 and Go 1.10 support, address outstanding pull requests (if possible)
+- 1.0. Final release.
+
 ## Contributing
 
-We welcome pull requests, bug fixes and issue reports. With that said, the bar for adding new symbols to this package is intentionally set high.
+Because of the Go2 errors changes, this package is not accepting proposals for new functionality. With that said, we welcome pull requests, bug fixes and issue reports. 
 
-Before proposing a change, please discuss your change by raising an issue.
+Before sending a PR, please discuss your change by raising an issue.
 
 ## License
 

vendor/github.com/pkg/errors/errors.go

@@ -82,7 +82,7 @@
 //
 //     if err, ok := err.(stackTracer); ok {
 //             for _, f := range err.StackTrace() {
-//                     fmt.Printf("%+s:%d", f)
+//                     fmt.Printf("%+s:%d\n", f, f)
 //             }
 //     }
 //
@@ -159,6 +159,9 @@ type withStack struct {
 
 func (w *withStack) Cause() error { return w.error }
 
+// Unwrap provides compatibility for Go 1.13 error chains.
+func (w *withStack) Unwrap() error { return w.error }
+
 func (w *withStack) Format(s fmt.State, verb rune) {
 	switch verb {
 	case 'v':
@@ -241,6 +244,9 @@ type withMessage struct {
 func (w *withMessage) Error() string { return w.msg + ": " + w.cause.Error() }
 func (w *withMessage) Cause() error  { return w.cause }
 
+// Unwrap provides compatibility for Go 1.13 error chains.
+func (w *withMessage) Unwrap() error { return w.cause }
+
 func (w *withMessage) Format(s fmt.State, verb rune) {
 	switch verb {
 	case 'v':

vendor/github.com/pkg/errors/go113.go

@@ -0,0 +1,38 @@
+// +build go1.13
+
+package errors
+
+import (
+	stderrors "errors"
+)
+
+// Is reports whether any error in err's chain matches target.
+//
+// The chain consists of err itself followed by the sequence of errors obtained by
+// repeatedly calling Unwrap.
+//
+// An error is considered to match a target if it is equal to that target or if
+// it implements a method Is(error) bool such that Is(target) returns true.
+func Is(err, target error) bool { return stderrors.Is(err, target) }
+
+// As finds the first error in err's chain that matches target, and if so, sets
+// target to that error value and returns true.
+//
+// The chain consists of err itself followed by the sequence of errors obtained by
+// repeatedly calling Unwrap.
+//
+// An error matches target if the error's concrete value is assignable to the value
+// pointed to by target, or if the error has a method As(interface{}) bool such that
+// As(target) returns true. In the latter case, the As method is responsible for
+// setting target.
+//
+// As will panic if target is not a non-nil pointer to either a type that implements
+// error, or to any interface type. As returns false if err is nil.
+func As(err error, target interface{}) bool { return stderrors.As(err, target) }
+
+// Unwrap returns the result of calling the Unwrap method on err, if err's
+// type contains an Unwrap method returning error.
+// Otherwise, Unwrap returns nil.
+func Unwrap(err error) error {
+	return stderrors.Unwrap(err)
+}

vendor/github.com/pkg/errors/stack.go

@@ -5,10 +5,13 @@ import (
 	"io"
 	"path"
 	"runtime"
+	"strconv"
 	"strings"
 )
 
 // Frame represents a program counter inside a stack frame.
+// For historical reasons if Frame is interpreted as a uintptr
+// its value represents the program counter + 1.
 type Frame uintptr
 
 // pc returns the program counter for this frame;
@@ -37,6 +40,15 @@ func (f Frame) line() int {
 	return line
 }
 
+// name returns the name of this function, if known.
+func (f Frame) name() string {
+	fn := runtime.FuncForPC(f.pc())
+	if fn == nil {
+		return "unknown"
+	}
+	return fn.Name()
+}
+
 // Format formats the frame according to the fmt.Formatter interface.
 //
 //    %s    source file
@@ -54,22 +66,16 @@ func (f Frame) Format(s fmt.State, verb rune) {
 	case 's':
 		switch {
 		case s.Flag('+'):
-			pc := f.pc()
-			fn := runtime.FuncForPC(pc)
-			if fn == nil {
-				io.WriteString(s, "unknown")
-			} else {
-				file, _ := fn.FileLine(pc)
-				fmt.Fprintf(s, "%s\n\t%s", fn.Name(), file)
-			}
+			io.WriteString(s, f.name())
+			io.WriteString(s, "\n\t")
+			io.WriteString(s, f.file())
 		default:
 			io.WriteString(s, path.Base(f.file()))
 		}
 	case 'd':
-		fmt.Fprintf(s, "%d", f.line())
+		io.WriteString(s, strconv.Itoa(f.line()))
 	case 'n':
-		name := runtime.FuncForPC(f.pc()).Name()
-		io.WriteString(s, funcname(name))
+		io.WriteString(s, funcname(f.name()))
 	case 'v':
 		f.Format(s, 's')
 		io.WriteString(s, ":")
@@ -77,6 +83,16 @@ func (f Frame) Format(s fmt.State, verb rune) {
 	}
 }
 
+// MarshalText formats a stacktrace Frame as a text string. The output is the
+// same as that of fmt.Sprintf("%+v", f), but without newlines or tabs.
+func (f Frame) MarshalText() ([]byte, error) {
+	name := f.name()
+	if name == "unknown" {
+		return []byte(name), nil
+	}
+	return []byte(fmt.Sprintf("%s %s:%d", name, f.file(), f.line())), nil
+}
+
 // StackTrace is stack of Frames from innermost (newest) to outermost (oldest).
 type StackTrace []Frame
 
@@ -94,18 +110,32 @@ func (st StackTrace) Format(s fmt.State, verb rune) {
 		switch {
 		case s.Flag('+'):
 			for _, f := range st {
-				fmt.Fprintf(s, "\n%+v", f)
+				io.WriteString(s, "\n")
+				f.Format(s, verb)
 			}
 		case s.Flag('#'):
 			fmt.Fprintf(s, "%#v", []Frame(st))
 		default:
-			fmt.Fprintf(s, "%v", []Frame(st))
+			st.formatSlice(s, verb)
 		}
 	case 's':
-		fmt.Fprintf(s, "%s", []Frame(st))
+		st.formatSlice(s, verb)
 	}
 }
 
+// formatSlice will format this StackTrace into the given buffer as a slice of
+// Frame, only valid when called with '%s' or '%v'.
+func (st StackTrace) formatSlice(s fmt.State, verb rune) {
+	io.WriteString(s, "[")
+	for i, f := range st {
+		if i > 0 {
+			io.WriteString(s, " ")
+		}
+		f.Format(s, verb)
+	}
+	io.WriteString(s, "]")
+}
+
 // stack represents a stack of program counters.
 type stack []uintptr
 

vendor/modules.txt

@@ -17,7 +17,7 @@ github.com/BurntSushi/toml
 github.com/PuerkitoBio/purell
 # github.com/PuerkitoBio/urlesc v0.0.0-20170810143723-de5bf2ad4578
 github.com/PuerkitoBio/urlesc
-# github.com/armon/go-proxyproto v0.0.0-20190211145416-68259f75880e
+# github.com/armon/go-proxyproto v0.0.0-20200108142055-f0b8253b1507
 github.com/armon/go-proxyproto
 # github.com/beorn7/perks v1.0.1
 github.com/beorn7/perks/quantile
@@ -127,7 +127,7 @@ github.com/mailru/easyjson/jlexer
 github.com/mailru/easyjson/jwriter
 # github.com/matttproud/golang_protobuf_extensions v1.0.1
 github.com/matttproud/golang_protobuf_extensions/pbutil
-# github.com/mitchellh/go-ps v0.0.0-20170309133038-4fdf99ab2936
+# github.com/mitchellh/go-ps v1.0.0
 github.com/mitchellh/go-ps
 # github.com/mitchellh/hashstructure v1.0.0
 github.com/mitchellh/hashstructure
@@ -191,11 +191,9 @@ github.com/opencontainers/runc/libcontainer/configs
 github.com/opencontainers/runtime-spec/specs-go
 # github.com/parnurzeal/gorequest v0.2.16
 github.com/parnurzeal/gorequest
-# github.com/paultag/sniff v0.0.0-20170624152000-87325c3dddf4
-github.com/paultag/sniff/parser
 # github.com/peterbourgon/diskv v2.0.1+incompatible
 github.com/peterbourgon/diskv
-# github.com/pkg/errors v0.8.1
+# github.com/pkg/errors v0.9.1
 github.com/pkg/errors
 # github.com/prometheus/client_golang v1.4.0
 github.com/prometheus/client_golang/prometheus
@@ -803,6 +801,8 @@ k8s.io/utils/pointer
 k8s.io/utils/trace
 # moul.io/http2curl v1.0.0
 moul.io/http2curl
+# pault.ag/go/sniff v0.0.0-20200207005214-cf7e4d167732
+pault.ag/go/sniff/parser
 # sigs.k8s.io/controller-runtime v0.4.0
 sigs.k8s.io/controller-runtime/pkg/client/config
 sigs.k8s.io/controller-runtime/pkg/envtest

vendor/pault.ag/go/sniff/parser/parser.go

@@ -44,6 +44,14 @@ func GetHostname(data []byte) (string, error) {
 	return string(sni), nil
 }
 
+/* Return the length computed from the two octets starting at index */
+func lengthFromData(data []byte, index int) int {
+	b1 := int(data[index])
+	b2 := int(data[index+1])
+
+	return (b1 << 8) + b2
+}
+
 /* Given a Server Name TLS Extension block, parse out and return the SNI
  * (Server Name Indication) payload */
 func GetSNIBlock(data []byte) ([]byte, error) {
@@ -53,11 +61,11 @@ func GetSNIBlock(data []byte) ([]byte, error) {
 		if index >= len(data) {
 			break
 		}
-		length := int((data[index] << 8) + data[index+1])
+		length := lengthFromData(data, index)
 		endIndex := index + 2 + length
 		if data[index+2] == 0x00 { /* SNI */
 			sni := data[index+3:]
-			sniLength := int((sni[0] << 8) + sni[1])
+			sniLength := lengthFromData(sni, 0)
 			return sni[2 : sniLength+2], nil
 		}
 		index = endIndex
@@ -75,17 +83,17 @@ func GetSNBlock(data []byte) ([]byte, error) {
 		return []byte{}, fmt.Errorf("Not enough bytes to be an SN block")
 	}
 
-	extensionLength := int((data[index] << 8) + data[index+1])
+	extensionLength := lengthFromData(data, index)
 	if extensionLength+2 > len(data) {
 		return []byte{}, fmt.Errorf("Extension looks bonkers")
 	}
 	data = data[2 : extensionLength+2]
 
 	for {
-		if index+3 >= len(data) {
+		if index+4 >= len(data) {
 			break
 		}
-		length := int((data[index+2] << 8) + data[index+3])
+		length := lengthFromData(data, index+2)
 		endIndex := index + 4 + length
 		if data[index] == 0x00 && data[index+1] == 0x00 {
 			return data[index+4 : endIndex], nil
@@ -121,7 +129,7 @@ func GetExtensionBlock(data []byte) ([]byte, error) {
 	}
 
 	/* Index is at Cipher List Length bits */
-	if newIndex := (index + 2 + int((data[index]<<8)+data[index+1])); (newIndex + 1) < len(data) {
+	if newIndex := (index + 2 + lengthFromData(data, index)); (newIndex + 1) < len(data) {
 		index = newIndex
 	} else {
 		return []byte{}, fmt.Errorf("Not enough bytes for the Cipher List")