Use mattermost v5 module (#1192)

vendor/github.com/go-asn1-ber/asn1-ber/.travis.yml

@@ -0,0 +1,38 @@
+language: go
+matrix:
+    include:
+        - go: 1.2.x
+          env: GOOS=linux GOARCH=amd64
+        - go: 1.2.x
+          env: GOOS=linux GOARCH=386
+        - go: 1.2.x
+          env: GOOS=windows GOARCH=amd64
+        - go: 1.2.x
+          env: GOOS=windows GOARCH=386
+        - go: 1.3.x
+        - go: 1.4.x
+        - go: 1.5.x
+        - go: 1.6.x
+        - go: 1.7.x
+        - go: 1.8.x
+        - go: 1.9.x
+        - go: 1.10.x
+        - go: 1.11.x
+        - go: 1.12.x
+        - go: 1.13.x
+          env: GOOS=linux GOARCH=amd64
+        - go: 1.13.x
+          env: GOOS=linux GOARCH=386
+        - go: 1.13.x
+          env: GOOS=windows GOARCH=amd64
+        - go: 1.13.x
+          env: GOOS=windows GOARCH=386
+        - go: tip
+go_import_path: gopkg.in/asn-ber.v1
+install:
+    - go list -f '{{range .Imports}}{{.}} {{end}}' ./... | xargs go get -v
+    - go list -f '{{range .TestImports}}{{.}} {{end}}' ./... | xargs go get -v
+    - go get code.google.com/p/go.tools/cmd/cover || go get golang.org/x/tools/cmd/cover
+    - go build -v ./...
+script:
+    - go test -v -cover ./... || go test -v ./...

vendor/github.com/go-asn1-ber/asn1-ber/LICENSE

@@ -0,0 +1,22 @@
+The MIT License (MIT)
+
+Copyright (c) 2011-2015 Michael Mitton (mmitton@gmail.com)
+Portions copyright (c) 2015-2016 go-asn1-ber Authors
+
+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/go-asn1-ber/asn1-ber/README.md

@@ -0,0 +1,24 @@
+[![GoDoc](https://godoc.org/gopkg.in/asn1-ber.v1?status.svg)](https://godoc.org/gopkg.in/asn1-ber.v1) [![Build Status](https://travis-ci.org/go-asn1-ber/asn1-ber.svg)](https://travis-ci.org/go-asn1-ber/asn1-ber)
+
+
+ASN1 BER Encoding / Decoding Library for the GO programming language.
+---------------------------------------------------------------------
+
+Required libraries: 
+   None
+
+Working:
+   Very basic encoding / decoding needed for LDAP protocol
+
+Tests Implemented:
+   A few
+
+TODO:
+   Fix all encoding / decoding to conform to ASN1 BER spec
+   Implement Tests / Benchmarks
+
+---
+
+The Go gopher was designed by Renee French. (http://reneefrench.blogspot.com/)
+The design is licensed under the Creative Commons 3.0 Attributions license.
+Read this article for more details: http://blog.golang.org/gopher

vendor/github.com/go-asn1-ber/asn1-ber/ber.go

@@ -0,0 +1,532 @@
+package ber
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"math"
+	"os"
+	"reflect"
+)
+
+// MaxPacketLengthBytes specifies the maximum allowed packet size when calling ReadPacket or DecodePacket. Set to 0 for
+// no limit.
+var MaxPacketLengthBytes int64 = math.MaxInt32
+
+type Packet struct {
+	Identifier
+	Value       interface{}
+	ByteValue   []byte
+	Data        *bytes.Buffer
+	Children    []*Packet
+	Description string
+}
+
+type Identifier struct {
+	ClassType Class
+	TagType   Type
+	Tag       Tag
+}
+
+type Tag uint64
+
+const (
+	TagEOC              Tag = 0x00
+	TagBoolean          Tag = 0x01
+	TagInteger          Tag = 0x02
+	TagBitString        Tag = 0x03
+	TagOctetString      Tag = 0x04
+	TagNULL             Tag = 0x05
+	TagObjectIdentifier Tag = 0x06
+	TagObjectDescriptor Tag = 0x07
+	TagExternal         Tag = 0x08
+	TagRealFloat        Tag = 0x09
+	TagEnumerated       Tag = 0x0a
+	TagEmbeddedPDV      Tag = 0x0b
+	TagUTF8String       Tag = 0x0c
+	TagRelativeOID      Tag = 0x0d
+	TagSequence         Tag = 0x10
+	TagSet              Tag = 0x11
+	TagNumericString    Tag = 0x12
+	TagPrintableString  Tag = 0x13
+	TagT61String        Tag = 0x14
+	TagVideotexString   Tag = 0x15
+	TagIA5String        Tag = 0x16
+	TagUTCTime          Tag = 0x17
+	TagGeneralizedTime  Tag = 0x18
+	TagGraphicString    Tag = 0x19
+	TagVisibleString    Tag = 0x1a
+	TagGeneralString    Tag = 0x1b
+	TagUniversalString  Tag = 0x1c
+	TagCharacterString  Tag = 0x1d
+	TagBMPString        Tag = 0x1e
+	TagBitmask          Tag = 0x1f // xxx11111b
+
+	// HighTag indicates the start of a high-tag byte sequence
+	HighTag Tag = 0x1f // xxx11111b
+	// HighTagContinueBitmask indicates the high-tag byte sequence should continue
+	HighTagContinueBitmask Tag = 0x80 // 10000000b
+	// HighTagValueBitmask obtains the tag value from a high-tag byte sequence byte
+	HighTagValueBitmask Tag = 0x7f // 01111111b
+)
+
+const (
+	// LengthLongFormBitmask is the mask to apply to the length byte to see if a long-form byte sequence is used
+	LengthLongFormBitmask = 0x80
+	// LengthValueBitmask is the mask to apply to the length byte to get the number of bytes in the long-form byte sequence
+	LengthValueBitmask = 0x7f
+
+	// LengthIndefinite is returned from readLength to indicate an indefinite length
+	LengthIndefinite = -1
+)
+
+var tagMap = map[Tag]string{
+	TagEOC:              "EOC (End-of-Content)",
+	TagBoolean:          "Boolean",
+	TagInteger:          "Integer",
+	TagBitString:        "Bit String",
+	TagOctetString:      "Octet String",
+	TagNULL:             "NULL",
+	TagObjectIdentifier: "Object Identifier",
+	TagObjectDescriptor: "Object Descriptor",
+	TagExternal:         "External",
+	TagRealFloat:        "Real (float)",
+	TagEnumerated:       "Enumerated",
+	TagEmbeddedPDV:      "Embedded PDV",
+	TagUTF8String:       "UTF8 String",
+	TagRelativeOID:      "Relative-OID",
+	TagSequence:         "Sequence and Sequence of",
+	TagSet:              "Set and Set OF",
+	TagNumericString:    "Numeric String",
+	TagPrintableString:  "Printable String",
+	TagT61String:        "T61 String",
+	TagVideotexString:   "Videotex String",
+	TagIA5String:        "IA5 String",
+	TagUTCTime:          "UTC Time",
+	TagGeneralizedTime:  "Generalized Time",
+	TagGraphicString:    "Graphic String",
+	TagVisibleString:    "Visible String",
+	TagGeneralString:    "General String",
+	TagUniversalString:  "Universal String",
+	TagCharacterString:  "Character String",
+	TagBMPString:        "BMP String",
+}
+
+type Class uint8
+
+const (
+	ClassUniversal   Class = 0   // 00xxxxxxb
+	ClassApplication Class = 64  // 01xxxxxxb
+	ClassContext     Class = 128 // 10xxxxxxb
+	ClassPrivate     Class = 192 // 11xxxxxxb
+	ClassBitmask     Class = 192 // 11xxxxxxb
+)
+
+var ClassMap = map[Class]string{
+	ClassUniversal:   "Universal",
+	ClassApplication: "Application",
+	ClassContext:     "Context",
+	ClassPrivate:     "Private",
+}
+
+type Type uint8
+
+const (
+	TypePrimitive   Type = 0  // xx0xxxxxb
+	TypeConstructed Type = 32 // xx1xxxxxb
+	TypeBitmask     Type = 32 // xx1xxxxxb
+)
+
+var TypeMap = map[Type]string{
+	TypePrimitive:   "Primitive",
+	TypeConstructed: "Constructed",
+}
+
+var Debug bool = false
+
+func PrintBytes(out io.Writer, buf []byte, indent string) {
+	data_lines := make([]string, (len(buf)/30)+1)
+	num_lines := make([]string, (len(buf)/30)+1)
+
+	for i, b := range buf {
+		data_lines[i/30] += fmt.Sprintf("%02x ", b)
+		num_lines[i/30] += fmt.Sprintf("%02d ", (i+1)%100)
+	}
+
+	for i := 0; i < len(data_lines); i++ {
+		out.Write([]byte(indent + data_lines[i] + "\n"))
+		out.Write([]byte(indent + num_lines[i] + "\n\n"))
+	}
+}
+
+func WritePacket(out io.Writer, p *Packet) {
+	printPacket(out, p, 0, false)
+}
+
+func PrintPacket(p *Packet) {
+	printPacket(os.Stdout, p, 0, false)
+}
+
+func printPacket(out io.Writer, p *Packet, indent int, printBytes bool) {
+	indent_str := ""
+
+	for len(indent_str) != indent {
+		indent_str += " "
+	}
+
+	class_str := ClassMap[p.ClassType]
+
+	tagtype_str := TypeMap[p.TagType]
+
+	tag_str := fmt.Sprintf("0x%02X", p.Tag)
+
+	if p.ClassType == ClassUniversal {
+		tag_str = tagMap[p.Tag]
+	}
+
+	value := fmt.Sprint(p.Value)
+	description := ""
+
+	if p.Description != "" {
+		description = p.Description + ": "
+	}
+
+	fmt.Fprintf(out, "%s%s(%s, %s, %s) Len=%d %q\n", indent_str, description, class_str, tagtype_str, tag_str, p.Data.Len(), value)
+
+	if printBytes {
+		PrintBytes(out, p.Bytes(), indent_str)
+	}
+
+	for _, child := range p.Children {
+		printPacket(out, child, indent+1, printBytes)
+	}
+}
+
+// ReadPacket reads a single Packet from the reader
+func ReadPacket(reader io.Reader) (*Packet, error) {
+	p, _, err := readPacket(reader)
+	if err != nil {
+		return nil, err
+	}
+	return p, nil
+}
+
+func DecodeString(data []byte) string {
+	return string(data)
+}
+
+func ParseInt64(bytes []byte) (ret int64, err error) {
+	if len(bytes) > 8 {
+		// We'll overflow an int64 in this case.
+		err = fmt.Errorf("integer too large")
+		return
+	}
+	for bytesRead := 0; bytesRead < len(bytes); bytesRead++ {
+		ret <<= 8
+		ret |= int64(bytes[bytesRead])
+	}
+
+	// Shift up and down in order to sign extend the result.
+	ret <<= 64 - uint8(len(bytes))*8
+	ret >>= 64 - uint8(len(bytes))*8
+	return
+}
+
+func encodeInteger(i int64) []byte {
+	n := int64Length(i)
+	out := make([]byte, n)
+
+	var j int
+	for ; n > 0; n-- {
+		out[j] = (byte(i >> uint((n-1)*8)))
+		j++
+	}
+
+	return out
+}
+
+func int64Length(i int64) (numBytes int) {
+	numBytes = 1
+
+	for i > 127 {
+		numBytes++
+		i >>= 8
+	}
+
+	for i < -128 {
+		numBytes++
+		i >>= 8
+	}
+
+	return
+}
+
+// DecodePacket decodes the given bytes into a single Packet
+// If a decode error is encountered, nil is returned.
+func DecodePacket(data []byte) *Packet {
+	p, _, _ := readPacket(bytes.NewBuffer(data))
+
+	return p
+}
+
+// DecodePacketErr decodes the given bytes into a single Packet
+// If a decode error is encountered, nil is returned
+func DecodePacketErr(data []byte) (*Packet, error) {
+	p, _, err := readPacket(bytes.NewBuffer(data))
+	if err != nil {
+		return nil, err
+	}
+	return p, nil
+}
+
+// readPacket reads a single Packet from the reader, returning the number of bytes read
+func readPacket(reader io.Reader) (*Packet, int, error) {
+	identifier, length, read, err := readHeader(reader)
+	if err != nil {
+		return nil, read, err
+	}
+
+	p := &Packet{
+		Identifier: identifier,
+	}
+
+	p.Data = new(bytes.Buffer)
+	p.Children = make([]*Packet, 0, 2)
+	p.Value = nil
+
+	if p.TagType == TypeConstructed {
+		// TODO: if universal, ensure tag type is allowed to be constructed
+
+		// Track how much content we've read
+		contentRead := 0
+		for {
+			if length != LengthIndefinite {
+				// End if we've read what we've been told to
+				if contentRead == length {
+					break
+				}
+				// Detect if a packet boundary didn't fall on the expected length
+				if contentRead > length {
+					return nil, read, fmt.Errorf("expected to read %d bytes, read %d", length, contentRead)
+				}
+			}
+
+			// Read the next packet
+			child, r, err := readPacket(reader)
+			if err != nil {
+				return nil, read, err
+			}
+			contentRead += r
+			read += r
+
+			// Test is this is the EOC marker for our packet
+			if isEOCPacket(child) {
+				if length == LengthIndefinite {
+					break
+				}
+				return nil, read, errors.New("eoc child not allowed with definite length")
+			}
+
+			// Append and continue
+			p.AppendChild(child)
+		}
+		return p, read, nil
+	}
+
+	if length == LengthIndefinite {
+		return nil, read, errors.New("indefinite length used with primitive type")
+	}
+
+	// Read definite-length content
+	if MaxPacketLengthBytes > 0 && int64(length) > MaxPacketLengthBytes {
+		return nil, read, fmt.Errorf("length %d greater than maximum %d", length, MaxPacketLengthBytes)
+	}
+	content := make([]byte, length, length)
+	if length > 0 {
+		_, err := io.ReadFull(reader, content)
+		if err != nil {
+			if err == io.EOF {
+				return nil, read, io.ErrUnexpectedEOF
+			}
+			return nil, read, err
+		}
+		read += length
+	}
+
+	if p.ClassType == ClassUniversal {
+		p.Data.Write(content)
+		p.ByteValue = content
+
+		switch p.Tag {
+		case TagEOC:
+		case TagBoolean:
+			val, _ := ParseInt64(content)
+
+			p.Value = val != 0
+		case TagInteger:
+			p.Value, _ = ParseInt64(content)
+		case TagBitString:
+		case TagOctetString:
+			// the actual string encoding is not known here
+			// (e.g. for LDAP content is already an UTF8-encoded
+			// string). Return the data without further processing
+			p.Value = DecodeString(content)
+		case TagNULL:
+		case TagObjectIdentifier:
+		case TagObjectDescriptor:
+		case TagExternal:
+		case TagRealFloat:
+		case TagEnumerated:
+			p.Value, _ = ParseInt64(content)
+		case TagEmbeddedPDV:
+		case TagUTF8String:
+			p.Value = DecodeString(content)
+		case TagRelativeOID:
+		case TagSequence:
+		case TagSet:
+		case TagNumericString:
+		case TagPrintableString:
+			p.Value = DecodeString(content)
+		case TagT61String:
+		case TagVideotexString:
+		case TagIA5String:
+		case TagUTCTime:
+		case TagGeneralizedTime:
+		case TagGraphicString:
+		case TagVisibleString:
+		case TagGeneralString:
+		case TagUniversalString:
+		case TagCharacterString:
+		case TagBMPString:
+		}
+	} else {
+		p.Data.Write(content)
+	}
+
+	return p, read, nil
+}
+
+func (p *Packet) Bytes() []byte {
+	var out bytes.Buffer
+
+	out.Write(encodeIdentifier(p.Identifier))
+	out.Write(encodeLength(p.Data.Len()))
+	out.Write(p.Data.Bytes())
+
+	return out.Bytes()
+}
+
+func (p *Packet) AppendChild(child *Packet) {
+	p.Data.Write(child.Bytes())
+	p.Children = append(p.Children, child)
+}
+
+func Encode(ClassType Class, TagType Type, Tag Tag, Value interface{}, Description string) *Packet {
+	p := new(Packet)
+
+	p.ClassType = ClassType
+	p.TagType = TagType
+	p.Tag = Tag
+	p.Data = new(bytes.Buffer)
+
+	p.Children = make([]*Packet, 0, 2)
+
+	p.Value = Value
+	p.Description = Description
+
+	if Value != nil {
+		v := reflect.ValueOf(Value)
+
+		if ClassType == ClassUniversal {
+			switch Tag {
+			case TagOctetString:
+				sv, ok := v.Interface().(string)
+
+				if ok {
+					p.Data.Write([]byte(sv))
+				}
+			}
+		}
+	}
+
+	return p
+}
+
+func NewSequence(Description string) *Packet {
+	return Encode(ClassUniversal, TypeConstructed, TagSequence, nil, Description)
+}
+
+func NewBoolean(ClassType Class, TagType Type, Tag Tag, Value bool, Description string) *Packet {
+	intValue := int64(0)
+
+	if Value {
+		intValue = 1
+	}
+
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	p.Data.Write(encodeInteger(intValue))
+
+	return p
+}
+
+// NewLDAPBoolean returns a RFC 4511-compliant Boolean packet
+func NewLDAPBoolean(Value bool, Description string) *Packet {
+	intValue := int64(0)
+
+	if Value {
+		intValue = 255
+	}
+
+	p := Encode(ClassUniversal, TypePrimitive, TagBoolean, nil, Description)
+
+	p.Value = Value
+	p.Data.Write(encodeInteger(intValue))
+
+	return p
+}
+
+func NewInteger(ClassType Class, TagType Type, Tag Tag, Value interface{}, Description string) *Packet {
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	switch v := Value.(type) {
+	case int:
+		p.Data.Write(encodeInteger(int64(v)))
+	case uint:
+		p.Data.Write(encodeInteger(int64(v)))
+	case int64:
+		p.Data.Write(encodeInteger(v))
+	case uint64:
+		// TODO : check range or add encodeUInt...
+		p.Data.Write(encodeInteger(int64(v)))
+	case int32:
+		p.Data.Write(encodeInteger(int64(v)))
+	case uint32:
+		p.Data.Write(encodeInteger(int64(v)))
+	case int16:
+		p.Data.Write(encodeInteger(int64(v)))
+	case uint16:
+		p.Data.Write(encodeInteger(int64(v)))
+	case int8:
+		p.Data.Write(encodeInteger(int64(v)))
+	case uint8:
+		p.Data.Write(encodeInteger(int64(v)))
+	default:
+		// TODO : add support for big.Int ?
+		panic(fmt.Sprintf("Invalid type %T, expected {u|}int{64|32|16|8}", v))
+	}
+
+	return p
+}
+
+func NewString(ClassType Class, TagType Type, Tag Tag, Value, Description string) *Packet {
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	p.Data.Write([]byte(Value))
+
+	return p
+}

vendor/github.com/go-asn1-ber/asn1-ber/content_int.go

@@ -0,0 +1,25 @@
+package ber
+
+func encodeUnsignedInteger(i uint64) []byte {
+	n := uint64Length(i)
+	out := make([]byte, n)
+
+	var j int
+	for ; n > 0; n-- {
+		out[j] = (byte(i >> uint((n-1)*8)))
+		j++
+	}
+
+	return out
+}
+
+func uint64Length(i uint64) (numBytes int) {
+	numBytes = 1
+
+	for i > 255 {
+		numBytes++
+		i >>= 8
+	}
+
+	return
+}

vendor/github.com/go-asn1-ber/asn1-ber/go.mod

@@ -0,0 +1,3 @@
+module github.com/go-asn1-ber/asn1-ber
+
+go 1.13

vendor/github.com/go-asn1-ber/asn1-ber/header.go

@@ -0,0 +1,35 @@
+package ber
+
+import (
+	"errors"
+	"fmt"
+	"io"
+)
+
+func readHeader(reader io.Reader) (identifier Identifier, length int, read int, err error) {
+	if i, c, err := readIdentifier(reader); err != nil {
+		return Identifier{}, 0, read, err
+	} else {
+		identifier = i
+		read += c
+	}
+
+	if l, c, err := readLength(reader); err != nil {
+		return Identifier{}, 0, read, err
+	} else {
+		length = l
+		read += c
+	}
+
+	// Validate length type with identifier (x.600, 8.1.3.2.a)
+	if length == LengthIndefinite && identifier.TagType == TypePrimitive {
+		return Identifier{}, 0, read, errors.New("indefinite length used with primitive type")
+	}
+
+	if length < LengthIndefinite {
+		err = fmt.Errorf("length cannot be less than %d", LengthIndefinite)
+		return
+	}
+
+	return identifier, length, read, nil
+}

vendor/github.com/go-asn1-ber/asn1-ber/identifier.go

@@ -0,0 +1,112 @@
+package ber
+
+import (
+	"errors"
+	"fmt"
+	"io"
+)
+
+func readIdentifier(reader io.Reader) (Identifier, int, error) {
+	identifier := Identifier{}
+	read := 0
+
+	// identifier byte
+	b, err := readByte(reader)
+	if err != nil {
+		if Debug {
+			fmt.Printf("error reading identifier byte: %v\n", err)
+		}
+		return Identifier{}, read, err
+	}
+	read++
+
+	identifier.ClassType = Class(b) & ClassBitmask
+	identifier.TagType = Type(b) & TypeBitmask
+
+	if tag := Tag(b) & TagBitmask; tag != HighTag {
+		// short-form tag
+		identifier.Tag = tag
+		return identifier, read, nil
+	}
+
+	// high-tag-number tag
+	tagBytes := 0
+	for {
+		b, err := readByte(reader)
+		if err != nil {
+			if Debug {
+				fmt.Printf("error reading high-tag-number tag byte %d: %v\n", tagBytes, err)
+			}
+			return Identifier{}, read, err
+		}
+		tagBytes++
+		read++
+
+		// Lowest 7 bits get appended to the tag value (x.690, 8.1.2.4.2.b)
+		identifier.Tag <<= 7
+		identifier.Tag |= Tag(b) & HighTagValueBitmask
+
+		// First byte may not be all zeros (x.690, 8.1.2.4.2.c)
+		if tagBytes == 1 && identifier.Tag == 0 {
+			return Identifier{}, read, errors.New("invalid first high-tag-number tag byte")
+		}
+		// Overflow of int64
+		// TODO: support big int tags?
+		if tagBytes > 9 {
+			return Identifier{}, read, errors.New("high-tag-number tag overflow")
+		}
+
+		// Top bit of 0 means this is the last byte in the high-tag-number tag (x.690, 8.1.2.4.2.a)
+		if Tag(b)&HighTagContinueBitmask == 0 {
+			break
+		}
+	}
+
+	return identifier, read, nil
+}
+
+func encodeIdentifier(identifier Identifier) []byte {
+	b := []byte{0x0}
+	b[0] |= byte(identifier.ClassType)
+	b[0] |= byte(identifier.TagType)
+
+	if identifier.Tag < HighTag {
+		// Short-form
+		b[0] |= byte(identifier.Tag)
+	} else {
+		// high-tag-number
+		b[0] |= byte(HighTag)
+
+		tag := identifier.Tag
+
+		b = append(b, encodeHighTag(tag)...)
+	}
+	return b
+}
+
+func encodeHighTag(tag Tag) []byte {
+	// set cap=4 to hopefully avoid additional allocations
+	b := make([]byte, 0, 4)
+	for tag != 0 {
+		// t := last 7 bits of tag (HighTagValueBitmask = 0x7F)
+		t := tag & HighTagValueBitmask
+
+		// right shift tag 7 to remove what was just pulled off
+		tag >>= 7
+
+		// if b already has entries this entry needs a continuation bit (0x80)
+		if len(b) != 0 {
+			t |= HighTagContinueBitmask
+		}
+
+		b = append(b, byte(t))
+	}
+	// reverse
+	// since bits were pulled off 'tag' small to high the byte slice is in reverse order.
+	// example: tag = 0xFF results in {0x7F, 0x01 + 0x80 (continuation bit)}
+	// this needs to be reversed into 0x81 0x7F
+	for i, j := 0, len(b)-1; i < len(b)/2; i++ {
+		b[i], b[j-i] = b[j-i], b[i]
+	}
+	return b
+}

vendor/github.com/go-asn1-ber/asn1-ber/length.go

@@ -0,0 +1,81 @@
+package ber
+
+import (
+	"errors"
+	"fmt"
+	"io"
+)
+
+func readLength(reader io.Reader) (length int, read int, err error) {
+	// length byte
+	b, err := readByte(reader)
+	if err != nil {
+		if Debug {
+			fmt.Printf("error reading length byte: %v\n", err)
+		}
+		return 0, 0, err
+	}
+	read++
+
+	switch {
+	case b == 0xFF:
+		// Invalid 0xFF (x.600, 8.1.3.5.c)
+		return 0, read, errors.New("invalid length byte 0xff")
+
+	case b == LengthLongFormBitmask:
+		// Indefinite form, we have to decode packets until we encounter an EOC packet (x.600, 8.1.3.6)
+		length = LengthIndefinite
+
+	case b&LengthLongFormBitmask == 0:
+		// Short definite form, extract the length from the bottom 7 bits (x.600, 8.1.3.4)
+		length = int(b) & LengthValueBitmask
+
+	case b&LengthLongFormBitmask != 0:
+		// Long definite form, extract the number of length bytes to follow from the bottom 7 bits (x.600, 8.1.3.5.b)
+		lengthBytes := int(b) & LengthValueBitmask
+		// Protect against overflow
+		// TODO: support big int length?
+		if lengthBytes > 8 {
+			return 0, read, errors.New("long-form length overflow")
+		}
+
+		// Accumulate into a 64-bit variable
+		var length64 int64
+		for i := 0; i < lengthBytes; i++ {
+			b, err = readByte(reader)
+			if err != nil {
+				if Debug {
+					fmt.Printf("error reading long-form length byte %d: %v\n", i, err)
+				}
+				return 0, read, err
+			}
+			read++
+
+			// x.600, 8.1.3.5
+			length64 <<= 8
+			length64 |= int64(b)
+		}
+
+		// Cast to a platform-specific integer
+		length = int(length64)
+		// Ensure we didn't overflow
+		if int64(length) != length64 {
+			return 0, read, errors.New("long-form length overflow")
+		}
+
+	default:
+		return 0, read, errors.New("invalid length byte")
+	}
+
+	return length, read, nil
+}
+
+func encodeLength(length int) []byte {
+	length_bytes := encodeUnsignedInteger(uint64(length))
+	if length > 127 || len(length_bytes) > 1 {
+		longFormBytes := []byte{(LengthLongFormBitmask | byte(len(length_bytes)))}
+		longFormBytes = append(longFormBytes, length_bytes...)
+		length_bytes = longFormBytes
+	}
+	return length_bytes
+}

vendor/github.com/go-asn1-ber/asn1-ber/util.go

@@ -0,0 +1,24 @@
+package ber
+
+import "io"
+
+func readByte(reader io.Reader) (byte, error) {
+	bytes := make([]byte, 1, 1)
+	_, err := io.ReadFull(reader, bytes)
+	if err != nil {
+		if err == io.EOF {
+			return 0, io.ErrUnexpectedEOF
+		}
+		return 0, err
+	}
+	return bytes[0], nil
+}
+
+func isEOCPacket(p *Packet) bool {
+	return p != nil &&
+		p.Tag == TagEOC &&
+		p.ClassType == ClassUniversal &&
+		p.TagType == TypePrimitive &&
+		len(p.ByteValue) == 0 &&
+		len(p.Children) == 0
+}