Log tested index MAC for each mutation

Author: tulir

appstate/decode.go

@@ -223,6 +223,7 @@ func (proc *Processor) decodeMutations(
 			Hex("index_mac", indexMAC).
 			Hex("value_mac", valueMAC).
 			Strs("index", index).
+			Stringer("operation", mutation.GetOperation()).
 			Msg("DEBUG: mutation metadata")
 		if mutation.GetOperation() == waServerSync.SyncdMutation_REMOVE {
 			out.RemoveMAC(indexMAC)
@@ -396,6 +397,7 @@ func (proc *Processor) evilHackForLIDMutation(
 	newIndexMAC = concatAndHMAC(sha256.New, keys.Index, indexBytes)
 	currentKeyID := mutation.GetRecord().GetKeyID().GetID()
 	triedIndexMACs := map[string]string{hex.EncodeToString(currentKeyID): hex.EncodeToString(newIndexMAC)}
+	moreMetadata := map[int]map[string]any{}
 	for i := mutationNum - 1; i >= 0; i-- {
 		newKeyID := prevMutations[i].GetRecord().GetKeyID().GetID()
 		if !bytes.Equal(currentKeyID, newKeyID) {
@@ -407,14 +409,24 @@ func (proc *Processor) evilHackForLIDMutation(
 			newIndexMAC = concatAndHMAC(sha256.New, keys.Index, indexBytes)
 			triedIndexMACs[hex.EncodeToString(currentKeyID)] = hex.EncodeToString(newIndexMAC)
 		}
+		moreMetadata[i] = map[string]any{
+			"expected_mac": hex.EncodeToString(newIndexMAC),
+			"mac_at_idx":   hex.EncodeToString(prevMutations[i].GetRecord().GetIndex().GetBlob()),
+			"key_id":       hex.EncodeToString(newKeyID),
+		}
 		if bytes.Equal(prevMutations[i].GetRecord().GetIndex().GetBlob(), newIndexMAC) {
+			moreMetadata[i]["equal"] = true
+			moreMetadata[i]["op_is_set"] = prevMutations[i].GetOperation() == waServerSync.SyncdMutation_SET
 			if prevMutations[i].GetOperation() == waServerSync.SyncdMutation_SET {
 				value := prevMutations[i].GetRecord().GetValue().GetBlob()
 				newValueMAC = value[len(value)-32:]
+				break
 			} else {
 				// Found a REMOVE operation, no previous value
 				return nil, nil, nil
 			}
+		} else {
+			moreMetadata[i]["equal"] = false
 		}
 	}
 	if newValueMAC == nil && checkDatabase {
@@ -444,6 +456,7 @@ func (proc *Processor) evilHackForLIDMutation(
 			Hex("old_index_mac", oldIndexMAC).
 			Strs("new_index", newIndex).
 			Any("new_index_macs_attempted", triedIndexMACs).
+			Any("more_metadata", moreMetadata).
 			Msg("DEBUG: No PN value MAC found for LID mutation")
 	} else {
 		zerolog.Ctx(ctx).Debug().