Record Class HybridKexProfile

java.lang.Object

java.lang.Record

zeroecho.sdk.hybrid.kex.HybridKexProfile

Record Components:

hkdfSalt - optional HKDF salt (defensively copied), may be null

hkdfInfo - optional HKDF info/label (defensively copied), may be null

outLenBytes - length of derived keying material in bytes (1..8160)

public record HybridKexProfile(byte[] hkdfSalt, byte[] hkdfInfo, int outLenBytes)
extends Record

Profile for a hybrid key exchange (KEX) composition.

A hybrid KEX combines two independently derived secrets:

• a classic (pre-quantum) agreement secret produced by an AgreementContext (e.g. X25519, ECDH, DH), and
• a post-quantum agreement secret produced by a MessageAgreementContext (typically a KEM-style agreement such as ML-KEM).

The two secrets are combined using HKDF-SHA256 (RFC 5869) to produce a final keying material byte array of a caller-selected length. The default label is intended to make cross-protocol misuse harder by providing an explicit domain separator.

Notes

• This profile does not store algorithm identifiers on purpose; it focuses on KDF binding and output size. Algorithm selection happens in higher layers when constructing the two underlying contexts.
• salt is optional; if null/empty, HKDF uses a zero-filled salt as per RFC 5869 and Kdf.

Since:

1.0

Constructor Summary

Constructors

Constructor	Description
HybridKexProfile(byte[] hkdfSalt, byte[] hkdfInfo, int outLenBytes)	Canonical constructor with validation and defensive copies.

Method Summary

Modifier and Type	Method	Description
static HybridKexProfile	defaultProfile(int outLenBytes)	Constructs a profile with a default HKDF info label.
final boolean	equals(Object o)	Indicates whether some other object is "equal to" this one.
final int	hashCode()	Returns a hash code value for this object.
byte[]	hkdfInfo()	Returns an owned copy of the optional HKDF information.
byte[]	hkdfSalt()	Returns an owned copy of the optional HKDF salt.
int	outLenBytes()	Returns the value of the outLenBytes record component.
final String	toString()	Returns a string representation of this record class.

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

HybridKexProfile

public HybridKexProfile(byte[] hkdfSalt,
 byte[] hkdfInfo,
 int outLenBytes)

Canonical constructor with validation and defensive copies.

Parameters:

hkdfSalt - optional HKDF salt

hkdfInfo - optional HKDF info/label

outLenBytes - output length in bytes

Method Details

defaultProfile

public static HybridKexProfile defaultProfile(int outLenBytes)

Constructs a profile with a default HKDF info label.

Parameters:

outLenBytes - output length in bytes

Returns:

profile with default HKDF info label and no explicit salt

hkdfSalt

public byte[] hkdfSalt()

Returns an owned copy of the optional HKDF salt.

Returns:

salt copy, or null

hkdfInfo

public byte[] hkdfInfo()

Returns an owned copy of the optional HKDF information.

Returns:

information copy, or null

toString

public final String toString()

Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.

Specified by:

toString in class Record

Returns:

a string representation of this object

hashCode

public final int hashCode()

Returns a hash code value for this object. The value is derived from the hash code of each of the record components.

Specified by:

hashCode in class Record

Returns:

a hash code value for this object

equals

public final boolean equals(Object o)

Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. Reference components are compared with Objects::equals(Object,Object); primitive components are compared with the compare method from their corresponding wrapper classes.

Specified by:

equals in class Record

Parameters:

o - the object with which to compare

Returns:

true if this object is the same as the o argument; false otherwise.

outLenBytes

public int outLenBytes()

Returns the value of the outLenBytes record component.

Returns:

the value of the outLenBytes record component