1 // Copyright 2012 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_SECURE_HASH_H_ 6 #define CRYPTO_SECURE_HASH_H_ 7 8 #include <stddef.h> 9 10 #include <memory> 11 12 #include "crypto/crypto_export.h" 13 14 namespace crypto { 15 16 // A wrapper to calculate secure hashes incrementally, allowing to 17 // be used when the full input is not known in advance. The end result will the 18 // same as if we have the full input in advance. 19 class CRYPTO_EXPORT SecureHash { 20 public: 21 enum Algorithm { 22 SHA256, 23 SHA512, 24 }; 25 26 SecureHash(const SecureHash&) = delete; 27 SecureHash& operator=(const SecureHash&) = delete; 28 ~SecureHash()29 virtual ~SecureHash() {} 30 31 static std::unique_ptr<SecureHash> Create(Algorithm type); 32 33 virtual void Update(const void* input, size_t len) = 0; 34 virtual void Finish(void* output, size_t len) = 0; 35 virtual size_t GetHashLength() const = 0; 36 37 // Create a clone of this SecureHash. The returned clone and this both 38 // represent the same hash state. But from this point on, calling 39 // Update()/Finish() on either doesn't affect the state of the other. 40 virtual std::unique_ptr<SecureHash> Clone() const = 0; 41 42 protected: SecureHash()43 SecureHash() {} 44 }; 45 46 } // namespace crypto 47 48 #endif // CRYPTO_SECURE_HASH_H_ 49