com.google.crypto.tink.jwt

Class JwtHmacKey

java.lang.Object

com.google.crypto.tink.Key

com.google.crypto.tink.jwt.JwtMacKey

com.google.crypto.tink.jwt.JwtHmacKey

public class JwtHmacKey
extends JwtMacKey

Represents a JWT HMAC key to create and verify JWT using HMAC.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JwtHmacKey.Builder Helps creating new JwtHmacKey objects.

Method Summary

Modifier and Type	Method and Description
static JwtHmacKey.Builder	builder()
boolean	equalsKey(Key o) Returns true if the key is guaranteed to be equal to other.
Integer	getIdRequirementOrNull() Returns null if this key has no id requirement, otherwise the required id.
SecretBytes	getKeyBytes()
Optional<String>	getKid() Returns the "kid" to be used for this key.
JwtHmacParameters	getParameters() Returns a Parameters object containing all the information about the key which is not randomly chosen.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

builder

public static JwtHmacKey.Builder builder()

getKeyBytes

public SecretBytes getKeyBytes()

getKid

public Optional<String> getKid()

Returns the "kid" to be used for this key.

If present, this kid will be written into the kid header during computeMacAndEncode. If absent, no kid will be written.

If present, and the kid header is present, the contents of the kid header needs to match the return value of this function.

Specified by:

getKid in class JwtMacKey

getIdRequirementOrNull

@Nullable
public Integer getIdRequirementOrNull()

Description copied from class: Key

Returns null if this key has no id requirement, otherwise the required id.

Some keys, when they are in a keyset, are required to have a certain ID to work properly. This comes from the fact that Tink in some cases prefixes ciphertexts or signatures with the string 0x01<id>, where the ID is encoded in big endian (see the documentation of the key type for details), in which case the key requires a certain ID.

Specified by:

getIdRequirementOrNull in class Key

getParameters

public JwtHmacParameters getParameters()

Description copied from class: Key

Returns a Parameters object containing all the information about the key which is not randomly chosen.

Implementations need to ensure that getParameters().hasIdRequirement() returns true if and only if getIdRequirementOrNull is non-null.

Specified by:

getParameters in class JwtMacKey

equalsKey

public boolean equalsKey(Key o)

Description copied from class: Key

Returns true if the key is guaranteed to be equal to other.

Implementations are required to do this in constant time.

Note: this is allowed to return false even if two keys are guaranteed to represent the same function, but are represented differently. For example, a key is allowed to internally store the number of zero-bytes used as padding when a large number is represented as a byte array, and use this in the comparison.

Note: Tink Key objects should typically not override hashCode (because it could risk leaking key material). Hence, they typically also should not override equals.

Specified by:

equalsKey in class Key