xref: /aosp_15_r20/external/tink/cc/streaming_mac.h (revision e7b1675dde1b92d52ec075b0a92829627f2c52a5)
1 // Copyright 2017 Google Inc.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //     http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 //
15 ///////////////////////////////////////////////////////////////////////////////
16 
17 #ifndef TINK_STREAMING_MAC_H_
18 #define TINK_STREAMING_MAC_H_
19 
20 #include <memory>
21 #include <string>
22 
23 #include "absl/strings/string_view.h"
24 #include "tink/output_stream_with_result.h"
25 #include "tink/util/status.h"
26 #include "tink/util/statusor.h"
27 
28 namespace crypto {
29 namespace tink {
30 
31 ///////////////////////////////////////////////////////////////////////////////
32 // Interface for Streaming MACs (Message Authentication Codes).
33 // This interface should be used for authentication only, and not for other
34 // purposes (e.g., it should not be used to generate pseudorandom bytes).
35 class StreamingMac {
36  public:
37   // Returns an ComputeMacOutputStream, which when closed will return the
38   // message authentication code (MAC) of the data put into the stream.
39   virtual util::StatusOr<std::unique_ptr<OutputStreamWithResult<std::string>>>
40   NewComputeMacOutputStream() const = 0;
41 
42   // Returns an VerifyMacOutputStream which verifies if 'mac' is a correct
43   // message authentication code (MAC) for the data written to it.
44   virtual util::StatusOr<std::unique_ptr<OutputStreamWithResult<util::Status>>>
45   NewVerifyMacOutputStream(const std::string& mac_value) const = 0;
46 
47   virtual ~StreamingMac() = default;
48 };
49 
50 }  // namespace tink
51 }  // namespace crypto
52 
53 #endif  // TINK_STREAMING_MAC_H_
54