io.pkts.packet.sctp.SctpDataChunk Maven / Gradle / Ivy
package io.pkts.packet.sctp;
import io.pkts.buffer.Buffer;
public interface SctpDataChunk extends SctpChunk {
/**
* Flag: U bit
*
*
*
* The (U)nordered bit, if set to '1', indicates that this is an
* unordered DATA chunk, and there is no Stream Sequence Number
* assigned to this DATA chunk. Therefore, the receiver MUST ignore
* the Stream Sequence Number field.
*
* After reassembly (if necessary), unordered DATA chunks MUST be
* dispatched to the upper layer by the receiver without any attempt
* to reorder.
*
* If an unordered user message is fragmented, each fragment of the
* message MUST have its U bit set to '1'.
*
* (source: RFC 4960 Section 3.3.1)
*
* @return
*/
boolean isUnordered();
/**
* Flag: B bit
*
* (source: RFC 4960 Section 3.3.1)
*
* @return
*/
boolean isBeginningFragment();
/**
* Flag: E bit
*
*
* The (E)nding fragment bit, if set, indicates the last fragment of
* a user message.
*
* An unfragmented user message shall have both the B and E bits set to
* '1'. Setting both B and E bits to '0' indicates a middle fragment of
* a multi-fragment user message, as summarized in the following table:
*
*
* B E Description
* ============================================================
* | 1 0 | First piece of a fragmented user message |
* +----------------------------------------------------------+
* | 0 0 | Middle piece of a fragmented user message |
* +----------------------------------------------------------+
* | 0 1 | Last piece of a fragmented user message |
* +----------------------------------------------------------+
* | 1 1 | Unfragmented message |
* ============================================================
* | Table 1: Fragment Description Flags |
* ============================================================
*
*
* When a user message is fragmented into multiple chunks, the TSNs are
* used by the receiver to reassemble the message. This means that the
* TSNs for each fragment of a fragmented user message MUST be strictly
* sequential.
* (source: RFC 4960 Section 3.3.1)
*
* @return
*/
boolean isEndingFragment();
/**
* Flag: I bit
*
* By setting this bit, the sender of
* a DATA chunk indicates that the corresponding SACK chunk should not
* be delayed.
*
* (source: RFC 7053 Section 3)
*/
boolean isImmediate();
/**
* This value represents the TSN for this DATA chunk. The valid
* range of TSN is from 0 to 4294967295 (2**32 - 1). TSN wraps back
* to 0 after reaching 4294967295.
*
* (source: RFC 4960 Section 3.3.1)
*/
long getTransmissionSequenceNumber();
/**
* Identifies the stream to which the following user data belongs.
*
* (source: RFC 4960 Section 3.3.1)
*/
int getStreamIdentifier();
/**
* This value represents the Stream Sequence Number of the following
* user data within the stream S. Valid range is 0 to 65535.
*
* When a user message is fragmented by SCTP for transport, the same
* Stream Sequence Number MUST be carried in each of the fragments of
* the message.
*
* (source: RFC 4960 Section 3.3.1)
*/
int getStreamSequenceNumber();
/**
* This value represents an application (or upper layer) specified
* protocol identifier. This value is passed to SCTP by its upper
* layer and sent to its peer. This identifier is not used by SCTP
* but can be used by certain network entities, as well as by the
* peer application, to identify the type of information being
* carried in this DATA chunk. This field must be sent even in
* fragmented DATA chunks (to make sure it is available for agents in
* the middle of the network). Note that this field is NOT touched
* by an SCTP implementation; therefore, its byte order is NOT
* necessarily big endian. The upper layer is responsible for any
* byte order conversions to this field.
*
* The value 0 indicates that no application identifier is specified
* by the upper layer for this payload data.
*
* (source: RFC 4960 Section 3.3.1)
*/
long getPayloadProtocolIdentifier();
/**
* The actual payload of the data chunk. The returned buffer will not contain
* any potential padding.
*/
Buffer getUserData();
@Override
default Type getType() {
return Type.DATA;
}
}