bring in khatru and eventstore.

khatru/blossom/authorization.go

@@ -0,0 +1,45 @@
+package blossom
+
+import (
+	"encoding/base64"
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/mailru/easyjson"
+	"github.com/nbd-wtf/go-nostr"
+)
+
+func readAuthorization(r *http.Request) (*nostr.Event, error) {
+	token := r.Header.Get("Authorization")
+	if !strings.HasPrefix(token, "Nostr ") {
+		return nil, nil
+	}
+
+	eventj, err := base64.StdEncoding.DecodeString(token[6:])
+	if err != nil {
+		return nil, fmt.Errorf("invalid base64 token")
+	}
+	var evt nostr.Event
+	if err := easyjson.Unmarshal(eventj, &evt); err != nil {
+		return nil, fmt.Errorf("broken event")
+	}
+	if evt.Kind != 24242 || !evt.CheckID() {
+		return nil, fmt.Errorf("invalid event")
+	}
+	if ok, _ := evt.CheckSignature(); !ok {
+		return nil, fmt.Errorf("invalid signature")
+	}
+
+	expirationTag := evt.Tags.Find("expiration")
+	if expirationTag == nil {
+		return nil, fmt.Errorf("missing \"expiration\" tag")
+	}
+	expiration, _ := strconv.ParseInt(expirationTag[1], 10, 64)
+	if nostr.Timestamp(expiration) < nostr.Now() {
+		return nil, fmt.Errorf("event expired")
+	}
+
+	return &evt, nil
+}