84 lines
2.7 KiB
Go
84 lines
2.7 KiB
Go
|
package sctp
|
||
|
|
|
||
|
|
import (
|
||
|
|
"errors"
|
||
|
|
"fmt"
|
||
|
|
)
|
||
|
|
|
||
|
|
/*
|
||
|
|
chunkHeartbeat represents an SCTP Chunk of type HEARTBEAT
|
||
|
|
|
||
|
|
An endpoint should send this chunk to its peer endpoint to probe the
|
||
|
|
reachability of a particular destination transport address defined in
|
||
|
|
the present association.
|
||
|
|
|
||
|
|
The parameter field contains the Heartbeat Information, which is a
|
||
|
|
variable-length opaque data structure understood only by the sender.
|
||
|
|
|
||
|
|
|
||
|
|
0 1 2 3
|
||
|
|
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
||
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||
|
|
| Type = 4 | Chunk Flags | Heartbeat Length |
|
||
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||
|
|
| |
|
||
|
|
| Heartbeat Information TLV (Variable-Length) |
|
||
|
|
| |
|
||
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||
|
|
|
||
|
|
Defined as a variable-length parameter using the format described
|
||
|
|
in Section 3.2.1, i.e.:
|
||
|
|
|
||
|
|
Variable Parameters Status Type Value
|
||
|
|
-------------------------------------------------------------
|
||
|
|
heartbeat Info Mandatory 1
|
||
|
|
*/
|
||
|
|
type chunkHeartbeat struct {
|
||
|
|
chunkHeader
|
||
|
|
params []param
|
||
|
|
}
|
||
|
|
|
||
|
|
var (
|
||
|
|
errChunkTypeNotHeartbeat = errors.New("ChunkType is not of type HEARTBEAT")
|
||
|
|
errHeartbeatNotLongEnoughInfo = errors.New("heartbeat is not long enough to contain Heartbeat Info")
|
||
|
|
errParseParamTypeFailed = errors.New("failed to parse param type")
|
||
|
|
errHeartbeatParam = errors.New("heartbeat should only have HEARTBEAT param")
|
||
|
|
errHeartbeatChunkUnmarshal = errors.New("failed unmarshalling param in Heartbeat Chunk")
|
||
|
|
)
|
||
|
|
|
||
|
|
func (h *chunkHeartbeat) unmarshal(raw []byte) error {
|
||
|
|
if err := h.chunkHeader.unmarshal(raw); err != nil {
|
||
|
|
return err
|
||
|
|
} else if h.typ != ctHeartbeat {
|
||
|
|
return fmt.Errorf("%w: actually is %s", errChunkTypeNotHeartbeat, h.typ.String())
|
||
|
|
}
|
||
|
|
|
||
|
|
if len(raw) <= chunkHeaderSize {
|
||
|
|
return fmt.Errorf("%w: %d", errHeartbeatNotLongEnoughInfo, len(raw))
|
||
|
|
}
|
||
|
|
|
||
|
|
pType, err := parseParamType(raw[chunkHeaderSize:])
|
||
|
|
if err != nil {
|
||
|
|
return fmt.Errorf("%w: %v", errParseParamTypeFailed, err)
|
||
|
|
}
|
||
|
|
if pType != heartbeatInfo {
|
||
|
|
return fmt.Errorf("%w: instead have %s", errHeartbeatParam, pType.String())
|
||
|
|
}
|
||
|
|
|
||
|
|
p, err := buildParam(pType, raw[chunkHeaderSize:])
|
||
|
|
if err != nil {
|
||
|
|
return fmt.Errorf("%w: %v", errHeartbeatChunkUnmarshal, err)
|
||
|
|
}
|
||
|
|
h.params = append(h.params, p)
|
||
|
|
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
func (h *chunkHeartbeat) Marshal() ([]byte, error) {
|
||
|
|
return nil, errUnimplemented
|
||
|
|
}
|
||
|
|
|
||
|
|
func (h *chunkHeartbeat) check() (abort bool, err error) {
|
||
|
|
return false, nil
|
||
|
|
}
|