Class GroupFounding

java.lang.Object

ai.badmonkey.agentspaces.peering.node.GroupFounding

public final class GroupFounding
extends Object

Founds self-certifying groups and verifies their founding advertisements (spec §4.4, §5.1). A GroupID is the hash of the group's founding document, so possession of the document proves the name and, just as importantly, no one can publish a different policy under the same name: a receiver that re-derives the id from the document it was handed detects any substitution.

The founding document is defined precisely as follows.

1. The founding fields are the advertisement's immutable fields, in this order: name, founder (the issuer PeerID), issued, ttl, membershipPolicy, defaultStrategy, gossip — the record GroupFounding.FoundingFields, encoded as canonical CBOR by CborCodec.defaultCodec().
2. The founder signs those canonical bytes with its Ed25519 identity key (RFC 8032; deterministic, so the same founder founding the same fields always derives the same id).
3. The founding document is the record GroupFounding.FoundingDocument (the fields plus that signature), again as canonical CBOR, and GroupId = GroupId.fromFounding(canonical CBOR of the founding document).
4. The advertisement's id is "aspace://" + groupId.

verify(SignedGroupAdvertisement) accepts a SignedGroupAdvertisement only when the carried key hashes to the advertisement's issuer, the signature verifies under that key over the founding fields, the derived id equals the advertisement's group, and the id URI matches. Any group advertisement that arrives from the network MUST pass this check before a node acts on it; locally configured literal-id groups (the older PeerNode.joinGroup(GroupAdvertisement, ...)) are exempt only because their advertisement is local configuration the network cannot swap.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final record	GroupFounding.FoundingDocument	The founding document whose canonical CBOR hashes to the GroupID: the founding fields and the founder's signature over their canonical bytes.
static final record	GroupFounding.FoundingFields	The immutable founding fields of a group: everything a member relies on that no later party may change.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	URI_PREFIX	The URI scheme prefix a founding advertisement's id carries.

Method Summary

Modifier and Type	Method	Description
static GroupId	derive(GroupFounding.FoundingFields fields, byte[] signature)	Derives the self-certifying GroupID of a founding document.
static GroupFounding.FoundingFields	fieldsOf(GroupAdvertisement ad)	Extracts the founding fields of an advertisement, in canonical order.
static SignedGroupAdvertisement	found(PeerIdentity founder, String name, GroupAdvertisement.MembershipPolicy membershipPolicy, ConflictStrategyType defaultStrategy, GroupAdvertisement.GossipParameters gossip, Instant issued, Duration ttl)	Founds a group: signs the founding fields, derives the self-certifying GroupID, and returns the signed founding advertisement to join with and to serve to newcomers.
static boolean	verify(SignedGroupAdvertisement signed)	Verifies that a signed group advertisement is the genuine founding document of the group it names: the founder key hashes to the issuer, the signature verifies over the founding fields, the derived id equals advertisement().group(), and the id URI names that group.

Methods inherited from class Object

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

Field Details

URI_PREFIX

public static final String URI_PREFIX

The URI scheme prefix a founding advertisement's id carries.

See Also:

• Constant Field Values

Method Details

found

public static SignedGroupAdvertisement found(PeerIdentity founder,
 String name,
 GroupAdvertisement.MembershipPolicy membershipPolicy,
 ConflictStrategyType defaultStrategy,
 GroupAdvertisement.GossipParameters gossip,
 Instant issued,
 Duration ttl)

Founds a group: signs the founding fields, derives the self-certifying GroupID, and returns the signed founding advertisement to join with and to serve to newcomers.

Parameters:

founder - the founding identity (becomes the issuer)

name - the group name

membershipPolicy - who may join

defaultStrategy - the default conflict strategy of the group's spaces

gossip - the gossip parameters

issued - the founding instant

ttl - the advertisement's cache time-to-live

Returns:

the signed, self-certifying founding advertisement

derive

public static GroupId derive(GroupFounding.FoundingFields fields,
 byte[] signature)

Derives the self-certifying GroupID of a founding document.

Parameters:

fields - the founding fields

signature - the founder's signature over the fields' canonical bytes

Returns:

the GroupID

fieldsOf

public static GroupFounding.FoundingFields fieldsOf(GroupAdvertisement ad)

Extracts the founding fields of an advertisement, in canonical order.

Parameters:

ad - the advertisement

Returns:

its founding fields

verify

public static boolean verify(SignedGroupAdvertisement signed)

Verifies that a signed group advertisement is the genuine founding document of the group it names: the founder key hashes to the issuer, the signature verifies over the founding fields, the derived id equals advertisement().group(), and the id URI names that group.

Parameters:

signed - the signed advertisement

Returns:

true only when every check passes