mirror of
https://github.com/kidfromjupiter/nearby.git
synced 2026-09-14 22:56:12 -04:00
hai007
05ae5583f8
them with chromium ::crypto symbols of the same names. PiperOrigin-RevId: 684566882
111 lines
4.0 KiB
C++
111 lines
4.0 KiB
C++
// Copyright 2020 Google LLC
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// https://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
#ifndef THIRD_PARTY_NEARBY_INTERNAL_CRYPTO_ENCRYPTOR_H_
|
|
#define THIRD_PARTY_NEARBY_INTERNAL_CRYPTO_ENCRYPTOR_H_
|
|
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
|
|
#include <memory>
|
|
#include <optional>
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
#include "absl/strings/string_view.h"
|
|
#include "absl/types/optional.h"
|
|
#include "absl/types/span.h"
|
|
#include "internal/crypto_cros/crypto_export.h"
|
|
|
|
namespace nearby::crypto {
|
|
|
|
class SymmetricKey;
|
|
|
|
// This class implements encryption without authentication, which is usually
|
|
// unsafe. Prefer crypto::Aead for new code. If using this class, prefer the
|
|
// absl::Span and std::vector overloads over the absl::string_view and
|
|
// std::string overloads.
|
|
class CRYPTO_EXPORT Encryptor {
|
|
public:
|
|
enum Mode {
|
|
CBC,
|
|
CTR,
|
|
};
|
|
|
|
Encryptor();
|
|
~Encryptor();
|
|
|
|
// Initializes the encryptor using |key| and |iv|. Returns false if either the
|
|
// key or the initialization vector cannot be used.
|
|
//
|
|
// If |mode| is CBC, |iv| must not be empty; if it is CTR, then |iv| must be
|
|
// empty.
|
|
bool Init(const SymmetricKey* key, Mode mode, absl::string_view iv);
|
|
bool Init(const SymmetricKey* key, Mode mode, absl::Span<const uint8_t> iv);
|
|
|
|
// Encrypts |plaintext| into |ciphertext|. |plaintext| may only be empty if
|
|
// the mode is CBC.
|
|
bool Encrypt(absl::string_view plaintext, std::string* ciphertext);
|
|
bool Encrypt(absl::Span<const uint8_t> plaintext,
|
|
std::vector<uint8_t>* ciphertext);
|
|
|
|
// Decrypts |ciphertext| into |plaintext|. |ciphertext| must not be empty.
|
|
//
|
|
// WARNING: In CBC mode, Decrypt() returns false if it detects the padding
|
|
// in the decrypted plaintext is wrong. Padding errors can result from
|
|
// tampered ciphertext or a wrong decryption key. But successful decryption
|
|
// does not imply the authenticity of the data. The caller of Decrypt()
|
|
// must either authenticate the ciphertext before decrypting it, or take
|
|
// care to not report decryption failure. Otherwise it could inadvertently
|
|
// be used as a padding oracle to attack the crypto system.
|
|
bool Decrypt(absl::string_view ciphertext, std::string* plaintext);
|
|
bool Decrypt(absl::Span<const uint8_t> ciphertext,
|
|
std::vector<uint8_t>* plaintext);
|
|
|
|
// Sets the counter value when in CTR mode. Currently only 128-bits
|
|
// counter value is supported.
|
|
//
|
|
// Returns true only if update was successful.
|
|
bool SetCounter(absl::string_view counter);
|
|
bool SetCounter(absl::Span<const uint8_t> counter);
|
|
|
|
// TODO(albertb): Support streaming encryption.
|
|
|
|
private:
|
|
const SymmetricKey* key_;
|
|
Mode mode_;
|
|
|
|
bool CryptString(bool do_encrypt, absl::string_view input,
|
|
std::string* output);
|
|
bool CryptBytes(bool do_encrypt, absl::Span<const uint8_t> input,
|
|
std::vector<uint8_t>* output);
|
|
|
|
// On success, these helper functions return the number of bytes written to
|
|
// |output|.
|
|
size_t MaxOutput(bool do_encrypt, size_t length);
|
|
absl::optional<size_t> Crypt(bool do_encrypt, absl::Span<const uint8_t> input,
|
|
absl::Span<uint8_t> output);
|
|
absl::optional<size_t> CryptCTR(bool do_encrypt,
|
|
absl::Span<const uint8_t> input,
|
|
absl::Span<uint8_t> output);
|
|
|
|
// In CBC mode, the IV passed to Init(). In CTR mode, the counter value passed
|
|
// to SetCounter().
|
|
std::vector<uint8_t> iv_;
|
|
};
|
|
|
|
} // namespace nearby::crypto
|
|
|
|
#endif // THIRD_PARTY_NEARBY_INTERNAL_CRYPTO_ENCRYPTOR_H_
|