perf: sync protocol and core hardening updates

internal/rpc/message_idempotency.go

@@ -0,0 +1,84 @@
+package rpc
+
+import (
+	"crypto/sha256"
+	"fmt"
+
+	"github.com/gotd/td/bin"
+	"github.com/gotd/td/tg"
+)
+
+// rpcRequestFingerprint 在任何自动实体补全、链接预览解析或上传媒体落库之前，
+// 对客户端原始 TL request 取稳定指纹。这样 lost-response 重放不会因服务端派生
+// photo/document id、pending webpage 状态等变化而被误判为另一条消息。
+func rpcRequestFingerprint(req bin.Encoder) ([]byte, error) {
+	if req == nil {
+		return nil, fmt.Errorf("fingerprint rpc request: nil request")
+	}
+	var b bin.Buffer
+	if err := req.Encode(&b); err != nil {
+		return nil, fmt.Errorf("fingerprint rpc request: %w", err)
+	}
+	sum := sha256.Sum256(b.Raw())
+	return sum[:], nil
+}
+
+// sendMessageIdempotencyFingerprint fingerprints only the durable message intent.
+// clear_draft/background/update_stickersets_order are one-shot client-side delivery
+// hints: after a lost response DrKLO/TDesktop may legitimately retry the same
+// random_id without them. They must not turn an exact send replay into
+// RANDOM_ID_DUPLICATE.
+func sendMessageIdempotencyFingerprint(req *tg.MessagesSendMessageRequest) ([]byte, error) {
+	if req == nil {
+		return nil, fmt.Errorf("fingerprint messages.sendMessage: nil request")
+	}
+	clone := *req
+	clone.Flags = 0
+	clone.ClearDraft = false
+	clone.Background = false
+	clone.UpdateStickersetsOrder = false
+	return rpcRequestFingerprint(&clone)
+}
+
+func sendMediaIdempotencyFingerprint(req *tg.MessagesSendMediaRequest) ([]byte, error) {
+	if req == nil {
+		return nil, fmt.Errorf("fingerprint messages.sendMedia: nil request")
+	}
+	clone := *req
+	clone.Flags = 0
+	clone.ClearDraft = false
+	clone.Background = false
+	clone.UpdateStickersetsOrder = false
+	return rpcRequestFingerprint(&clone)
+}
+
+// sendMultiMediaItemIdempotencyFingerprint deliberately reduces a batch to one
+// InputSingleMedia. A retry containing only the failed subset therefore produces
+// the same fingerprint for every surviving random_id as the original batch.
+func sendMultiMediaItemIdempotencyFingerprint(req *tg.MessagesSendMultiMediaRequest, item tg.InputSingleMedia) ([]byte, error) {
+	if req == nil {
+		return nil, fmt.Errorf("fingerprint messages.sendMultiMedia item: nil request")
+	}
+	clone := *req
+	clone.Flags = 0
+	clone.ClearDraft = false
+	clone.Background = false
+	clone.UpdateStickersetsOrder = false
+	clone.MultiMedia = []tg.InputSingleMedia{item}
+	return rpcRequestFingerprint(&clone)
+}
+
+// forwardMessagesItemIdempotencyFingerprint makes the source message id and its
+// paired random_id the unit of idempotency. Hashing the full ID/RandomID vectors
+// incorrectly rejects a legal retry that contains only a failed subset.
+func forwardMessagesItemIdempotencyFingerprint(req *tg.MessagesForwardMessagesRequest, messageID int, randomID int64) ([]byte, error) {
+	if req == nil {
+		return nil, fmt.Errorf("fingerprint messages.forwardMessages item: nil request")
+	}
+	clone := *req
+	clone.Flags = 0
+	clone.Background = false
+	clone.ID = []int{messageID}
+	clone.RandomID = []int64{randomID}
+	return rpcRequestFingerprint(&clone)
+}