taler-mailbox

commit ee5c19e9edf7e4e0959becc99e97606d9e6de041
parent bec18e5abf34fbaef97aec8372934a27bdc15e7f
Author: Martin Schanzenbach <schanzen@gnunet.org>
Date:   Wed, 20 Jul 2022 13:27:25 +0200

check signature first

Diffstat:
M
pkg/rest/mailbox.go
 | 
44
++++++++++++++++++++++++--------------------

1 file changed, 24 insertions(+), 20 deletions(-)
diff --git a/pkg/rest/mailbox.go b/pkg/rest/mailbox.go
@@ -266,6 +266,29 @@ func (m *Mailbox) deleteMessagesResponse(w http.ResponseWriter, r *http.Request)
 		w.WriteHeader(http.StatusBadRequest)
 		return
 	}
+	checksum, err := gnunetutil.DecodeStringToBinary(msg.Checksum, 64)
+	if err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+	pk := ed25519.PublicKey(pkey)
+	sig, err := gnunetutil.DecodeStringToBinary(msg.WalletSig, 64)
+	if nil != err {
+		w.WriteHeader(http.StatusForbidden)
+		return
+	}
+	var signed_msg bytes.Buffer
+	size := make([]byte, 4)
+	binary.BigEndian.PutUint32(size, 64+4+4)
+	purp := make([]byte, 4)
+	binary.BigEndian.PutUint32(purp, 23) // FIXME purpose
+	signed_msg.Write(size)
+	signed_msg.Write(purp)
+	signed_msg.Write(checksum)
+	if !ed25519.Verify(pk, signed_msg.Bytes(), sig) {
+		w.WriteHeader(http.StatusForbidden)
+		return
+	}
 	h := sha512.New()
 	h.Write(pkey)
 	h_mailbox := gnunetutil.EncodeBinaryToString(h.Sum(nil))
@@ -293,29 +316,10 @@ func (m *Mailbox) deleteMessagesResponse(w http.ResponseWriter, r *http.Request)
 		h_all.Write(eph)
 		h_all.Write(body)
 	}
-	h_all_s := gnunetutil.EncodeBinaryToString(h_all.Sum(nil))
-	if h_all_s != msg.Checksum {
+	if 0 != bytes.Compare(h_all.Sum(nil), checksum) {
 		w.WriteHeader(http.StatusNotFound)
 		return
 	}
-	pk := ed25519.PublicKey(pkey)
-	sig, err := gnunetutil.DecodeStringToBinary(msg.WalletSig, 64)
-	if nil != err {
-		w.WriteHeader(http.StatusForbidden)
-		return
-	}
-	var signed_msg bytes.Buffer
-	size := make([]byte, 4)
-	binary.BigEndian.PutUint32(size, 64+4+4)
-	purp := make([]byte, 4)
-	binary.BigEndian.PutUint32(purp, 23) // FIXME purpose
-	signed_msg.Write(size)
-	signed_msg.Write(purp)
-	signed_msg.Write(h_all.Sum(nil))
-	if !ed25519.Verify(pk, signed_msg.Bytes(), sig) {
-		w.WriteHeader(http.StatusForbidden)
-		return
-	}
 	m.Db.Delete(&entries)
 	w.WriteHeader(http.StatusNoContent)
 }