record

Documentation

Index

• Constants
• Variables
• func CiphertextHeaderFirstByte(hasCID bool, has16bitSeqNum bool, hasLength bool, epoch uint16) byte
• func IsEncryptedRecord(fb byte) bool
• func RecordNumberCmp(a, b Number) int
• type AckParser
  • func NewAckParser(recordBody []byte) (AckParser, error)
  • func (p *AckParser) PopFront(epochSeqOverflowCounter *int) (rn Number, ok bool)
• type Alert
  • func AlertCloseNormal() Alert
  • func (msg *Alert) IsFatal() bool
  • func (msg *Alert) Parse(body []byte) (err error)
  • func (msg *Alert) Write(body []byte) []byte
• type Encrypted
  • func (hdr *Encrypted) ClosestSequenceNumber(seqNumData []byte, expectedSN uint64) (uint16, uint64)
  • func (hdr *Encrypted) Epoch() byte
  • func (hdr *Encrypted) Has16BitSeqNum() bool
  • func (hdr *Encrypted) HasCID() bool
  • func (hdr *Encrypted) HasLength() bool
  • func (hdr *Encrypted) MatchesEpoch(epoch uint16) bool
  • func (hdr *Encrypted) Parse(datagram []byte, cIDLength int) (n int, err error)
• type Number
  • func NumberWith(epoch uint16, seqNum uint64) Number
  • func (r Number) Epoch() uint16
  • func (r Number) Less(other Number) bool
  • func (r Number) SeqNum() uint64
• type Plaintext
  • func (hdr *Plaintext) Parse(datagram []byte) (n int, err error)
• type PlaintextHeader
  • func (hdr *PlaintextHeader) Write(datagram []byte, length uint16) []byte

Constants

const (
	// we use 0 as "no alert" indicator
	AlerLevelWarning = 1
	AlerLevelFatal   = 2
)

const (
	RecordTypeAlert           = 21
	RecordTypeHandshake       = 22
	RecordTypeApplicationData = 23
	// PlaintextContentTypeHeartbeat       = 24 // [rfc6520] should not be received without negotiating extension. We choose to error on it.
	RecordTypeAck = 26
)

const AckElementSize = 16

const AckHeaderSize = 2

const AlertSize = 2

const MaxCiphertextRecordLength = MaxPlaintextRecordLength + 256 // [rfc8446:5.2]

const MaxPlaintextRecordLength = 16384 // [rfc8446:5.1]

const MaxSeq = 0xFFFFFFFFFFFF

const OutgoingCiphertextRecordHeader16 = 5 // first byte + 8-bit seqnum + 16-bit length

const OutgoingCiphertextRecordHeader8 = 4 // first byte + 16-bit seqnum + 16-bit length

This does not include CID size and AEAD seal, they are deterministic but depend on runtime parameters

const PlaintextRecordHeaderSize = 13

Variables

var ErrAckRecordWrongSize = errors.New("ack record size not multiple of 16")

var ErrAlertLevelParsing = errors.New("alert level failed to parse")

var ErrCiphertextRecordBodyTooLong = errors.New("cipher text record body exceeds 2^14 + 256")

var ErrCiphertextRecordTooShort = errors.New("cipher text record header too short")

var ErrCiphertextRecordTooShortLength = errors.New("cipher text record body too short (explicit length)")

var ErrPlaintextRecordBodyEpochNonZero = errors.New("plaintext record body non zero epoch")

var ErrPlaintextRecordBodyTooLong = errors.New("plaintext record body exceeds 2^14")

var ErrPlaintextRecordBodyTooShort = errors.New("plaintext record body too short")

var ErrPlaintextRecordHeaderTooShort = errors.New("plaintext record header too short")

var ErrPlaintextRecordWrongLegacyRecordVersion = errors.New("plaintext record wrong legacy record version")

var ErrRecordTypeFailedToParse = errors.New("record type failed to parse")

Functions

func CiphertextHeaderFirstByte

func CiphertextHeaderFirstByte(hasCID bool, has16bitSeqNum bool, hasLength bool, epoch uint16) byte

func IsEncryptedRecord

func IsEncryptedRecord(fb byte) bool

func RecordNumberCmp

func RecordNumberCmp(a, b Number) int

Types

type AckParser

type AckParser struct {
	// contains filtered or unexported fields
}

func NewAckParser

func NewAckParser(recordBody []byte) (AckParser, error)

return by value to signal usage pattern

func (*AckParser) PopFront

func (p *AckParser) PopFront(epochSeqOverflowCounter *int) (rn Number, ok bool)

type Alert

type Alert struct {
	Level       byte
	Description byte
}

func AlertCloseNormal

func AlertCloseNormal() Alert

func (*Alert) IsFatal

func (msg *Alert) IsFatal() bool

func (*Alert) Parse

func (msg *Alert) Parse(body []byte) (err error)

func (*Alert) Write

func (msg *Alert) Write(body []byte) []byte

type Encrypted

type Encrypted struct {
	FirstByte byte
	CID       []byte // alias to original slice
	SeqNum    []byte // alias to original slice to be encrypted/decrypted in place
	Header    []byte // alias to original slice for AEAD
	// Length is checked, not stored
	Ciphertext []byte // alias to original slice
}

func (*Encrypted) ClosestSequenceNumber

func (hdr *Encrypted) ClosestSequenceNumber(seqNumData []byte, expectedSN uint64) (uint16, uint64)

func (*Encrypted) Epoch

func (hdr *Encrypted) Epoch() byte

func (*Encrypted) Has16BitSeqNum

func (hdr *Encrypted) Has16BitSeqNum() bool

func (*Encrypted) HasCID

func (hdr *Encrypted) HasCID() bool

func (*Encrypted) HasLength

func (hdr *Encrypted) HasLength() bool

func (*Encrypted) MatchesEpoch

func (hdr *Encrypted) MatchesEpoch(epoch uint16) bool

func (*Encrypted) Parse

func (hdr *Encrypted) Parse(datagram []byte, cIDLength int) (n int, err error)

type Number

type Number struct {
	// contains filtered or unexported fields
}

func NumberWith

func NumberWith(epoch uint16, seqNum uint64) Number

func (Number) Epoch

func (r Number) Epoch() uint16

func (Number) Less

func (r Number) Less(other Number) bool

func (Number) SeqNum

func (r Number) SeqNum() uint64

type Plaintext

type Plaintext struct {
	ContentType byte
	// Version is fixed, not stored
	// epoch is fixed to 0 for plaintext messages, do not store
	SequenceNumber uint64 // stored as 48-bit
	// Length is checked, not stored
	// Body is alias to buffer which must be parsed/saved and never retained
	Body []byte
}

func (*Plaintext) Parse

func (hdr *Plaintext) Parse(datagram []byte) (n int, err error)

type PlaintextHeader

type PlaintextHeader struct {
	ContentType byte
	// Version is fixed, not stored
	// epoch is fixed to 0 for plaintext messages, do not store
	SequenceNumber uint64 // stored as 48-bit

}

func (*PlaintextHeader) Write

func (hdr *PlaintextHeader) Write(datagram []byte, length uint16) []byte