sccp

README

go-sccp: SCCP in Golang

Package sccp provides simple and painless handling of SCCP(Signaling Connection Control Part) in SS7/SIGTRAN stack, implemented in the Go Programming Language.

Disclaimer

This is still an experimental project, and currently in its very early stage of development. Any part of implementations(including exported APIs) may be changed before released as v1.0.0.

Getting started

Run go mod tidy to download the dependency, and you're ready to start developing.

Supported Features

Message Types

Message type	Abbreviation	Reference	Supported?
Connection request	CR	4.2	-
Connection confirm	CC	4.3	-
Connection refused	CREF	4.4	-
Released	RLSD	4.5	-
Release complete	RLC	4.6	-
Data form 1	DT1	4.7	-
Data form 2	DT2	4.8	-
Data acknowledgement	AK	4.9	-
Unitdata	UDT	4.10	Yes
Unitdata service	UDTS	4.11	-
Expedited data	ED	4.12	-
Expedited data acknowledgement	EA	4.13	-
Reset request	RSR	4.14	-
Reset confirm	RSC	4.15	-
Protocol data unit error	ERR	4.16	-
Inactivity test	IT	4.17	-
Extended unitdata	XUDT	4.18	-
Extended unitdata service	XUDTS	4.19	-
Long unitdata	LUDT	4.20	-
Long unitdata service	LUDTS	4.21	-

Parameters

Parameter name	Reference	Supported?
End of optional parameters	3.1
Destination local reference	3.2
Source local reference	3.3
Called party address	3.4	Yes
Calling party address	3.5	Yes
Protocol class	3.6	Yes
Segmenting/reassembling	3.7
Receive sequence number	3.8
Sequencing/segmenting	3.9
Credit	3.10
Release cause	3.11
Return cause	3.12
Reset cause	3.13
Error cause	3.14
Refusal cause	3.15
Data	3.16	Yes
Segmentation	3.17
Hop counter	3.18
Importance	3.19
Long data	3.20

Author(s)

Yoshiyuki Kurauchi (Website / LinkedIn)

I'm always open to welcome co-authors! Please feel free to talk to me.

LICENSE

MIT

Documentation

Overview

Package sccp provides encoding/decoding feature of Signalling Connection Control Part used in SS7/SIGTRAN protocol stack.

This is still an experimental project, and currently in its very early stage of development. Any part of implementations (including exported APIs) may be changed before released as v1.0.0.

Index

• type Header
  • func NewHeader(mtype MsgType, payload []byte) *Header
  • func ParseHeader(b []byte) (*Header, error)
  • func (h *Header) MarshalBinary() ([]byte, error)
  • func (h *Header) MarshalLen() int
  • func (h *Header) MarshalTo(b []byte) error
  • func (h *Header) String() string
  • func (h *Header) UnmarshalBinary(b []byte) error
• type Message
  • func ParseMessage(b []byte) (Message, error)
• type MsgType
• type UDT
  • func NewUDT(pcls int, mhandle bool, cdpa, cgpa *params.PartyAddress, data []byte) *UDT
  • func ParseUDT(b []byte) (*UDT, error)
  • func (u *UDT) CdGT() string
  • func (u *UDT) CgGT() string
  • func (u *UDT) MarshalBinary() ([]byte, error)
  • func (u *UDT) MarshalLen() int
  • func (u *UDT) MarshalTo(b []byte) error
  • func (u *UDT) MessageType() MsgType
  • func (u *UDT) MessageTypeName() string
  • func (u *UDT) SetLength()
  • func (u *UDT) String() string
  • func (u *UDT) UnmarshalBinary(b []byte) error
• type UnsupportedTypeError
  • func (e UnsupportedTypeError) Error() string

Types

type Header

type Header struct {
	Type    MsgType
	Payload []byte
}

Header is a SCCP common header.

func NewHeader

func NewHeader(mtype MsgType, payload []byte) *Header

NewHeader creates a new Header.

func ParseHeader

func ParseHeader(b []byte) (*Header, error)

ParseHeader decodes given byte sequence as a SCCP common header.

func (*Header) MarshalBinary

func (h *Header) MarshalBinary() ([]byte, error)

MarshalBinary returns the byte sequence generated from a Header instance.

func (*Header) MarshalLen

func (h *Header) MarshalLen() int

MarshalLen returns the serial length.

func (*Header) MarshalTo

func (h *Header) MarshalTo(b []byte) error

MarshalTo puts the byte sequence in the byte array given as b.

func (*Header) String

func (h *Header) String() string

String returns the SCCP common header values in human readable format.

func (*Header) UnmarshalBinary

func (h *Header) UnmarshalBinary(b []byte) error

UnmarshalBinary sets the values retrieved from byte sequence in a SCCP common header.

type Message

type Message interface {
	encoding.BinaryMarshaler
	encoding.BinaryUnmarshaler
	MarshalTo([]byte) error
	MarshalLen() int
	MessageType() MsgType
	MessageTypeName() string
	fmt.Stringer
}

Message is an interface that defines SCCP messages.

func ParseMessage

func ParseMessage(b []byte) (Message, error)

ParseMessage decodes the byte sequence into Message by Message Type. Currently this only supports UDT type of message only.

type MsgType

type MsgType uint8

MsgType is type of SCCP message.

const (
	MsgTypeCR MsgType
	MsgTypeCC
	MsgTypeCREF
	MsgTypeRLSD
	MsgTypeRLC
	MsgTypeDT1
	MsgTypeDT2
	MsgTypeAK
	MsgTypeUDT
	MsgTypeUDTS
	MsgTypeED
	MsgTypeEA
	MsgTypeRSR
	MsgTypeRSC
	MsgTypeERR
	MsgTypeIT
	MsgTypeXUDT
	MsgTypeXUDTS
	MsgTypeLUDT
	MsgTypeLUDTS
)

Message Type definitions.

type UDT

type UDT struct {
	Type MsgType
	params.ProtocolClass
	Ptr1, Ptr2, Ptr3    uint8
	CalledPartyAddress  *params.PartyAddress
	CallingPartyAddress *params.PartyAddress
	DataLength          uint8
	Data                []byte
}

UDT represents a SCCP Message Unit Data(UDT).

func NewUDT

func NewUDT(pcls int, mhandle bool, cdpa, cgpa *params.PartyAddress, data []byte) *UDT

NewUDT creates a new UDT.

func ParseUDT

func ParseUDT(b []byte) (*UDT, error)

ParseUDT decodes given byte sequence as a SCCP UDT.

func (*UDT) CdGT

func (u *UDT) CdGT() string

CdGT returns the GT in CalledPartyAddress in human readable string.

func (*UDT) CgGT

func (u *UDT) CgGT() string

CgGT returns the GT in CalledPartyAddress in human readable string.

func (*UDT) MarshalBinary

func (u *UDT) MarshalBinary() ([]byte, error)

MarshalBinary returns the byte sequence generated from a UDT instance.

func (*UDT) MarshalLen

func (u *UDT) MarshalLen() int

MarshalLen returns the serial length.

func (*UDT) MarshalTo

func (u *UDT) MarshalTo(b []byte) error

MarshalTo puts the byte sequence in the byte array given as b. SCCP is dependent on the Pointers when serializing, which means that it might fail when invalid Pointers are set.

func (*UDT) MessageType

func (u *UDT) MessageType() MsgType

MessageType returns the Message Type in int.

func (*UDT) MessageTypeName

func (u *UDT) MessageTypeName() string

MessageTypeName returns the Message Type in string.

func (*UDT) SetLength

func (u *UDT) SetLength()

SetLength sets the length in Length field.

func (*UDT) String

func (u *UDT) String() string

String returns the UDT values in human readable format.

func (*UDT) UnmarshalBinary

func (u *UDT) UnmarshalBinary(b []byte) error

UnmarshalBinary sets the values retrieved from byte sequence in a SCCP UDT.

type UnsupportedTypeError

type UnsupportedTypeError byte

UnsupportedTypeError indicates the value in Version field is invalid.

func (UnsupportedTypeError) Error

func (e UnsupportedTypeError) Error() string

Error returns the type of receiver and some additional message.