1 files changed, 74 insertions, 0 deletions
diff --git a/internal/keydb/keyring.go b/internal/keydb/keyring.go
new file mode 100644
index 00000000..d0b1904e
--- /dev/null
+++ b/internal/keydb/keyring.go
@@ -0,0 +1,74 @@
+// Copyright 2017 New Vector Ltd
+//
+// 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.
+
+package keydb
+
+import (
+	"encoding/base64"
+
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/sirupsen/logrus"
+	"golang.org/x/crypto/ed25519"
+)
+
+// CreateKeyRing creates and configures a KeyRing object.
+//
+// It creates the necessary key fetchers and collects them into a KeyRing
+// backed by the given KeyDatabase.
+func CreateKeyRing(client gomatrixserverlib.Client,
+	keyDB gomatrixserverlib.KeyDatabase,
+	cfg config.KeyPerspectives) gomatrixserverlib.KeyRing {
+
+	fetchers := gomatrixserverlib.KeyRing{
+		KeyFetchers: []gomatrixserverlib.KeyFetcher{
+			&gomatrixserverlib.DirectKeyFetcher{
+				Client: client,
+			},
+		},
+		KeyDatabase: keyDB,
+	}
+
+	logrus.Info("Enabled direct key fetcher")
+
+	var b64e = base64.StdEncoding.WithPadding(base64.NoPadding)
+	for _, ps := range cfg {
+		perspective := &gomatrixserverlib.PerspectiveKeyFetcher{
+			PerspectiveServerName: ps.ServerName,
+			PerspectiveServerKeys: map[gomatrixserverlib.KeyID]ed25519.PublicKey{},
+			Client:                client,
+		}
+
+		for _, key := range ps.Keys {
+			rawkey, err := b64e.DecodeString(key.PublicKey)
+			if err != nil {
+				logrus.WithError(err).WithFields(logrus.Fields{
+					"server_name": ps.ServerName,
+					"public_key":  key.PublicKey,
+				}).Warn("Couldn't parse perspective key")
+				continue
+			}
+			perspective.PerspectiveServerKeys[key.KeyID] = rawkey
+		}
+
+		fetchers.KeyFetchers = append(fetchers.KeyFetchers, perspective)
+
+		logrus.WithFields(logrus.Fields{
+			"server_name":     ps.ServerName,
+			"num_public_keys": len(ps.Keys),
+		}).Info("Enabled perspective key fetcher")
+	}
+
+	return fetchers
+}