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