1 files changed, 492 insertions, 0 deletions
diff --git a/modules/asn1-ber/ber.go b/modules/asn1-ber/ber.go
new file mode 100644
index 0000000000..3e99a273c6
--- /dev/null
+++ b/modules/asn1-ber/ber.go
@@ -0,0 +1,492 @@
+package ber
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"reflect"
+)
+
+type Packet struct {
+	ClassType   uint8
+	TagType     uint8
+	Tag         uint8
+	Value       interface{}
+	ByteValue   []byte
+	Data        *bytes.Buffer
+	Children    []*Packet
+	Description string
+}
+
+const (
+	TagEOC              = 0x00
+	TagBoolean          = 0x01
+	TagInteger          = 0x02
+	TagBitString        = 0x03
+	TagOctetString      = 0x04
+	TagNULL             = 0x05
+	TagObjectIdentifier = 0x06
+	TagObjectDescriptor = 0x07
+	TagExternal         = 0x08
+	TagRealFloat        = 0x09
+	TagEnumerated       = 0x0a
+	TagEmbeddedPDV      = 0x0b
+	TagUTF8String       = 0x0c
+	TagRelativeOID      = 0x0d
+	TagSequence         = 0x10
+	TagSet              = 0x11
+	TagNumericString    = 0x12
+	TagPrintableString  = 0x13
+	TagT61String        = 0x14
+	TagVideotexString   = 0x15
+	TagIA5String        = 0x16
+	TagUTCTime          = 0x17
+	TagGeneralizedTime  = 0x18
+	TagGraphicString    = 0x19
+	TagVisibleString    = 0x1a
+	TagGeneralString    = 0x1b
+	TagUniversalString  = 0x1c
+	TagCharacterString  = 0x1d
+	TagBMPString        = 0x1e
+	TagBitmask          = 0x1f // xxx11111b
+)
+
+var TagMap = map[uint8]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",
+}
+
+const (
+	ClassUniversal   = 0   // 00xxxxxxb
+	ClassApplication = 64  // 01xxxxxxb
+	ClassContext     = 128 // 10xxxxxxb
+	ClassPrivate     = 192 // 11xxxxxxb
+	ClassBitmask     = 192 // 11xxxxxxb
+)
+
+var ClassMap = map[uint8]string{
+	ClassUniversal:   "Universal",
+	ClassApplication: "Application",
+	ClassContext:     "Context",
+	ClassPrivate:     "Private",
+}
+
+const (
+	TypePrimitive   = 0  // xx0xxxxxb
+	TypeConstructed = 32 // xx1xxxxxb
+	TypeBitmask     = 32 // xx1xxxxxb
+)
+
+var TypeMap = map[uint8]string{
+	TypePrimitive:   "Primative",
+	TypeConstructed: "Constructed",
+}
+
+var Debug bool = false
+
+func PrintBytes(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++ {
+		fmt.Print(indent + data_lines[i] + "\n")
+		fmt.Print(indent + num_lines[i] + "\n\n")
+	}
+}
+
+func PrintPacket(p *Packet) {
+	printPacket(p, 0, false)
+}
+
+func printPacket(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.Printf("%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(p.Bytes(), indent_str)
+	}
+
+	for _, child := range p.Children {
+		printPacket(child, indent+1, printBytes)
+	}
+}
+
+func resizeBuffer(in []byte, new_size uint64) (out []byte) {
+	out = make([]byte, new_size)
+
+	copy(out, in)
+
+	return
+}
+
+func readBytes(reader io.Reader, buf []byte) error {
+	idx := 0
+	buflen := len(buf)
+
+	for idx < buflen {
+		n, err := reader.Read(buf[idx:])
+		if err != nil {
+			return err
+		}
+		idx += n
+	}
+
+	return nil
+}
+
+func ReadPacket(reader io.Reader) (*Packet, error) {
+	buf := make([]byte, 2)
+
+	err := readBytes(reader, buf)
+
+	if err != nil {
+		return nil, err
+	}
+
+	idx := uint64(2)
+	datalen := uint64(buf[1])
+
+	if Debug {
+		fmt.Printf("Read: datalen = %d len(buf) = %d ", datalen, len(buf))
+
+		for _, b := range buf {
+			fmt.Printf("%02X ", b)
+		}
+
+		fmt.Printf("\n")
+	}
+
+	if datalen&128 != 0 {
+		a := datalen - 128
+
+		idx += a
+		buf = resizeBuffer(buf, 2+a)
+
+		err := readBytes(reader, buf[2:])
+
+		if err != nil {
+			return nil, err
+		}
+
+		datalen = DecodeInteger(buf[2 : 2+a])
+
+		if Debug {
+			fmt.Printf("Read: a = %d  idx = %d  datalen = %d  len(buf) = %d", a, idx, datalen, len(buf))
+
+			for _, b := range buf {
+				fmt.Printf("%02X ", b)
+			}
+
+			fmt.Printf("\n")
+		}
+	}
+
+	buf = resizeBuffer(buf, idx+datalen)
+	err = readBytes(reader, buf[idx:])
+
+	if err != nil {
+		return nil, err
+	}
+
+	if Debug {
+		fmt.Printf("Read: len( buf ) = %d  idx=%d datalen=%d idx+datalen=%d\n", len(buf), idx, datalen, idx+datalen)
+
+		for _, b := range buf {
+			fmt.Printf("%02X ", b)
+		}
+	}
+
+	p := DecodePacket(buf)
+
+	return p, nil
+}
+
+func DecodeString(data []byte) (ret string) {
+	for _, c := range data {
+		ret += fmt.Sprintf("%c", c)
+	}
+
+	return
+}
+
+func DecodeInteger(data []byte) (ret uint64) {
+	for _, i := range data {
+		ret = ret * 256
+		ret = ret + uint64(i)
+	}
+
+	return
+}
+
+func EncodeInteger(val uint64) []byte {
+	var out bytes.Buffer
+
+	found := false
+
+	shift := uint(56)
+
+	mask := uint64(0xFF00000000000000)
+
+	for mask > 0 {
+		if !found && (val&mask != 0) {
+			found = true
+		}
+
+		if found || (shift == 0) {
+			out.Write([]byte{byte((val & mask) >> shift)})
+		}
+
+		shift -= 8
+		mask = mask >> 8
+	}
+
+	return out.Bytes()
+}
+
+func DecodePacket(data []byte) *Packet {
+	p, _ := decodePacket(data)
+
+	return p
+}
+
+func decodePacket(data []byte) (*Packet, []byte) {
+	if Debug {
+		fmt.Printf("decodePacket: enter %d\n", len(data))
+	}
+
+	p := new(Packet)
+
+	p.ClassType = data[0] & ClassBitmask
+	p.TagType = data[0] & TypeBitmask
+	p.Tag = data[0] & TagBitmask
+
+	datalen := DecodeInteger(data[1:2])
+	datapos := uint64(2)
+
+	if datalen&128 != 0 {
+		datalen -= 128
+		datapos += datalen
+		datalen = DecodeInteger(data[2 : 2+datalen])
+	}
+
+	p.Data = new(bytes.Buffer)
+
+	p.Children = make([]*Packet, 0, 2)
+
+	p.Value = nil
+
+	value_data := data[datapos : datapos+datalen]
+
+	if p.TagType == TypeConstructed {
+		for len(value_data) != 0 {
+			var child *Packet
+
+			child, value_data = decodePacket(value_data)
+			p.AppendChild(child)
+		}
+	} else if p.ClassType == ClassUniversal {
+		p.Data.Write(data[datapos : datapos+datalen])
+		p.ByteValue = value_data
+
+		switch p.Tag {
+		case TagEOC:
+		case TagBoolean:
+			val := DecodeInteger(value_data)
+
+			p.Value = val != 0
+		case TagInteger:
+			p.Value = DecodeInteger(value_data)
+		case TagBitString:
+		case TagOctetString:
+			p.Value = DecodeString(value_data)
+		case TagNULL:
+		case TagObjectIdentifier:
+		case TagObjectDescriptor:
+		case TagExternal:
+		case TagRealFloat:
+		case TagEnumerated:
+			p.Value = DecodeInteger(value_data)
+		case TagEmbeddedPDV:
+		case TagUTF8String:
+		case TagRelativeOID:
+		case TagSequence:
+		case TagSet:
+		case TagNumericString:
+		case TagPrintableString:
+			p.Value = DecodeString(value_data)
+		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(data[datapos : datapos+datalen])
+	}
+
+	return p, data[datapos+datalen:]
+}
+
+func (p *Packet) DataLength() uint64 {
+	return uint64(p.Data.Len())
+}
+
+func (p *Packet) Bytes() []byte {
+	var out bytes.Buffer
+
+	out.Write([]byte{p.ClassType | p.TagType | p.Tag})
+	packet_length := EncodeInteger(p.DataLength())
+
+	if p.DataLength() > 127 || len(packet_length) > 1 {
+		out.Write([]byte{byte(len(packet_length) | 128)})
+		out.Write(packet_length)
+	} else {
+		out.Write(packet_length)
+	}
+
+	out.Write(p.Data.Bytes())
+
+	return out.Bytes()
+}
+
+func (p *Packet) AppendChild(child *Packet) {
+	p.Data.Write(child.Bytes())
+
+	if len(p.Children) == cap(p.Children) {
+		newChildren := make([]*Packet, cap(p.Children)*2)
+
+		copy(newChildren, p.Children)
+		p.Children = newChildren[0:len(p.Children)]
+	}
+
+	p.Children = p.Children[0 : len(p.Children)+1]
+	p.Children[len(p.Children)-1] = child
+}
+
+func Encode(ClassType, TagType, Tag uint8, 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, TypePrimitive, TagSequence, nil, Description)
+}
+
+func NewBoolean(ClassType, TagType, Tag uint8, Value bool, Description string) *Packet {
+	intValue := 0
+
+	if Value {
+		intValue = 1
+	}
+
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	p.Data.Write(EncodeInteger(uint64(intValue)))
+
+	return p
+}
+
+func NewInteger(ClassType, TagType, Tag uint8, Value uint64, Description string) *Packet {
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	p.Data.Write(EncodeInteger(Value))
+
+	return p
+}
+
+func NewString(ClassType, TagType, Tag uint8, Value, Description string) *Packet {
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	p.Data.Write([]byte(Value))
+
+	return p
+}