Safe Haskell	None
Language	GHC2021

LibP2P.DHT.Validator

Contents

Validator interface
Built-in validators
Key helpers

Description

Record validation for the Kademlia DHT.

Per specs/kad-dht (Entry validation), records must be validated on two occasions: values retrieved in a GET_VALUE query and values received in a PUT_VALUE query before storing them locally.

Record keys have the form namespacepath; validation dispatches on the namespace, mirroring go-libp2p's record.NamespacedValidator. The built-in pk validator binds the key to the value: the path must be the multihash (Peer ID) of the serialized public key carried in the value.

Synopsis

data Validator = Validator {
- valValidate :: ByteString -> ByteString -> Either String ()
- valSelect :: ByteString -> [ByteString] -> Either String Int
}
namespacedValidator :: Map ByteString Validator -> Validator
pkValidator :: Validator
defaultValidator :: Validator
splitRecordKey :: ByteString -> Either String (ByteString, ByteString)

Validator interface

data Validator Source #

Validator interface for record validation.

valValidate checks that a value is well-formed for its key and returns an error for records that must not be stored or served. valSelect picks the index of the best value among conflicting candidates for the same key (used for GET_VALUE conflict resolution).

Constructors

Validator
Fields valValidate :: ByteString -> ByteString -> Either String () valSelect :: ByteString -> [ByteString] -> Either String Int

Built-in validators

namespacedValidator :: Map ByteString Validator -> Validator Source #

Dispatch validation by key namespace. Keys without a registered namespace are rejected, matching go-libp2p's namespaced validator ("invalid record keytype").

pkValidator :: Validator Source #

Validator for the pk namespace: the value must be a serialized PublicKey protobuf whose derived Peer ID equals the multihash in the key path. Public keys never conflict, so valSelect keeps the first candidate (go-libp2p's record.PublicKeyValidator does the same).

defaultValidator :: Validator Source #

The default validator set: pk records only. Additional namespaces can be registered by building a custom namespacedValidator and storing it in the DHT node.

Key helpers

splitRecordKey :: ByteString -> Either String (ByteString, ByteString) Source #

Split a record key of the form namespacepath into (namespace, path). The path is raw bytes (for pk it is a binary multihash), so only the two leading separators are interpreted.