1 // Copyright 2015 The Chromium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CRYPTO_AEAD_H_ 6 #define CRYPTO_AEAD_H_ 7 8 #include <stddef.h> 9 #include <stdint.h> 10 11 #include <string> 12 #include <vector> 13 14 #include "base/containers/span.h" 15 #include "base/memory/raw_ptr.h" 16 #include "base/strings/string_piece.h" 17 #include "crypto/crypto_export.h" 18 #include "third_party/abseil-cpp/absl/types/optional.h" 19 20 struct evp_aead_st; 21 22 namespace crypto { 23 24 // This class exposes the AES-128-CTR-HMAC-SHA256 and AES_256_GCM AEAD. Note 25 // that there are two versions of most methods: an historical version based 26 // around |StringPiece| and a more modern version that takes |base::span|. 27 // Prefer the latter in new code. 28 class CRYPTO_EXPORT Aead { 29 public: 30 enum AeadAlgorithm { 31 AES_128_CTR_HMAC_SHA256, 32 AES_256_GCM, 33 AES_256_GCM_SIV, 34 CHACHA20_POLY1305 35 }; 36 37 explicit Aead(AeadAlgorithm algorithm); 38 Aead(const Aead&) = delete; 39 Aead& operator=(const Aead&) = delete; 40 ~Aead(); 41 42 // Note that Init keeps a reference to the data pointed to by |key| thus that 43 // data must outlive this object. 44 void Init(base::span<const uint8_t> key); 45 46 // Note that Init keeps a reference to the data pointed to by |key| thus that 47 // data must outlive this object. 48 void Init(const std::string* key); 49 50 std::vector<uint8_t> Seal(base::span<const uint8_t> plaintext, 51 base::span<const uint8_t> nonce, 52 base::span<const uint8_t> additional_data) const; 53 54 bool Seal(base::StringPiece plaintext, 55 base::StringPiece nonce, 56 base::StringPiece additional_data, 57 std::string* ciphertext) const; 58 59 absl::optional<std::vector<uint8_t>> Open( 60 base::span<const uint8_t> ciphertext, 61 base::span<const uint8_t> nonce, 62 base::span<const uint8_t> additional_data) const; 63 64 bool Open(base::StringPiece ciphertext, 65 base::StringPiece nonce, 66 base::StringPiece additional_data, 67 std::string* plaintext) const; 68 69 size_t KeyLength() const; 70 71 size_t NonceLength() const; 72 73 private: 74 bool Seal(base::span<const uint8_t> plaintext, 75 base::span<const uint8_t> nonce, 76 base::span<const uint8_t> additional_data, 77 uint8_t* out, 78 size_t* output_length, 79 size_t max_output_length) const; 80 81 bool Open(base::span<const uint8_t> ciphertext, 82 base::span<const uint8_t> nonce, 83 base::span<const uint8_t> additional_data, 84 uint8_t* out, 85 size_t* output_length, 86 size_t max_output_length) const; 87 88 absl::optional<base::span<const uint8_t>> key_; 89 raw_ptr<const evp_aead_st> aead_; 90 }; 91 92 } // namespace crypto 93 94 #endif // CRYPTO_AEAD_H_ 95