dendrite/cmd/dendritejs/keyfetcher.go

87 lines
3.1 KiB
Go

// Copyright 2020 The Matrix.org Foundation C.I.C.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// +build wasm
package main
import (
"context"
"fmt"
"time"
"github.com/libp2p/go-libp2p-core/peer"
"github.com/matrix-org/gomatrixserverlib"
)
const libp2pMatrixKeyID = "ed25519:libp2p-dendrite"
type libp2pKeyFetcher struct {
}
// FetchKeys looks up a batch of public keys.
// Takes a map from (server name, key ID) pairs to timestamp.
// The timestamp is when the keys need to be vaild up to.
// Returns a map from (server name, key ID) pairs to server key objects for
// that server name containing that key ID
// The result may have fewer (server name, key ID) pairs than were in the request.
// The result may have more (server name, key ID) pairs than were in the request.
// Returns an error if there was a problem fetching the keys.
func (f *libp2pKeyFetcher) FetchKeys(
ctx context.Context,
requests map[gomatrixserverlib.PublicKeyLookupRequest]gomatrixserverlib.Timestamp,
) (map[gomatrixserverlib.PublicKeyLookupRequest]gomatrixserverlib.PublicKeyLookupResult, error) {
res := make(map[gomatrixserverlib.PublicKeyLookupRequest]gomatrixserverlib.PublicKeyLookupResult)
for req := range requests {
if req.KeyID != libp2pMatrixKeyID {
return nil, fmt.Errorf("FetchKeys: cannot fetch key with ID %s, should be %s", req.KeyID, libp2pMatrixKeyID)
}
// The server name is a libp2p peer ID
peerIDStr := string(req.ServerName)
peerID, err := peer.Decode(peerIDStr)
if err != nil {
return nil, fmt.Errorf("Failed to decode peer ID from server name '%s': %w", peerIDStr, err)
}
pubKey, err := peerID.ExtractPublicKey()
if err != nil {
return nil, fmt.Errorf("Failed to extract public key from peer ID: %w", err)
}
pubKeyBytes, err := pubKey.Raw()
if err != nil {
return nil, fmt.Errorf("Failed to extract raw bytes from public key: %w", err)
}
b64Key := gomatrixserverlib.Base64String(pubKeyBytes)
res[req] = gomatrixserverlib.PublicKeyLookupResult{
VerifyKey: gomatrixserverlib.VerifyKey{
Key: b64Key,
},
ExpiredTS: gomatrixserverlib.PublicKeyNotExpired,
ValidUntilTS: gomatrixserverlib.AsTimestamp(time.Now().Add(24 * time.Hour * 365)),
}
}
return res, nil
}
// FetcherName returns the name of this fetcher, which can then be used for
// logging errors etc.
func (f *libp2pKeyFetcher) FetcherName() string {
return "libp2pKeyFetcher"
}
// no-op function for storing keys - we don't do any work to fetch them so don't bother storing.
func (f *libp2pKeyFetcher) StoreKeys(ctx context.Context, results map[gomatrixserverlib.PublicKeyLookupRequest]gomatrixserverlib.PublicKeyLookupResult) error {
return nil
}