diff options
Diffstat (limited to 'ber.go')
| -rw-r--r-- | ber.go | 60 |
1 files changed, 60 insertions, 0 deletions
@@ -132,12 +132,15 @@ func PrintPacket(p *Packet) { 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 { @@ -146,6 +149,7 @@ func printPacket(p *Packet, indent int, printBytes bool) { value := fmt.Sprint(p.Value) description := "" + if p.Description != "" { description = p.Description + ": " } @@ -163,13 +167,16 @@ func printPacket(p *Packet, indent int, printBytes bool) { 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 { @@ -177,56 +184,74 @@ func readBytes(reader io.Reader, buf []byte) error { } 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 } @@ -234,6 +259,7 @@ func DecodeString(data []byte) (ret string) { for _, c := range data { ret += fmt.Sprintf("%c", c) } + return } @@ -242,29 +268,38 @@ func DecodeInteger(data []byte) (ret uint64) { 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 } @@ -272,13 +307,16 @@ 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 @@ -286,7 +324,9 @@ func decodePacket(data []byte) (*Packet, []byte) { } p.Data = new(bytes.Buffer) + p.Children = make([]*Packet, 0, 2) + p.Value = nil value_data := data[datapos : datapos+datalen] @@ -294,6 +334,7 @@ func decodePacket(data []byte) (*Packet, []byte) { if p.TagType == TypeConstructed { for len(value_data) != 0 { var child *Packet + child, value_data = decodePacket(value_data) p.AppendChild(child) } @@ -305,6 +346,7 @@ func decodePacket(data []byte) (*Packet, []byte) { case TagEOC: case TagBoolean: val := DecodeInteger(value_data) + p.Value = val != 0 case TagInteger: p.Value = DecodeInteger(value_data) @@ -351,36 +393,46 @@ func (p *Packet) DataLength() uint64 { 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 @@ -391,6 +443,7 @@ func Encode(ClassType, TagType, Tag uint8, Value interface{}, Description string switch Tag { case TagOctetString: sv, ok := v.Interface().(string) + if ok { p.Data.Write([]byte(sv)) } @@ -407,26 +460,33 @@ func NewSequence(Description string) *Packet { 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 } |