1 // Copyright 2017 The Abseil Authors. 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 // https://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 #ifndef ABSL_RANDOM_INTERNAL_RANDEN_SLOW_H_ 16 #define ABSL_RANDOM_INTERNAL_RANDEN_SLOW_H_ 17 18 #include <cstddef> 19 20 #include "absl/base/config.h" 21 22 namespace absl { 23 ABSL_NAMESPACE_BEGIN 24 namespace random_internal { 25 26 // RANDen = RANDom generator or beetroots in Swiss German. 27 // RandenSlow implements the basic state manipulation methods for 28 // architectures lacking AES hardware acceleration intrinsics. 29 class RandenSlow { 30 public: 31 // Size of the entire sponge / state for the randen PRNG. 32 static constexpr size_t kStateBytes = 256; // 2048-bit 33 34 // Size of the 'inner' (inaccessible) part of the sponge. Larger values would 35 // require more frequent calls to RandenGenerate. 36 static constexpr size_t kCapacityBytes = 16; // 128-bit 37 38 static void Generate(const void* keys, void* state_void); 39 static void Absorb(const void* seed_void, void* state_void); 40 static const void* GetKeys(); 41 }; 42 43 } // namespace random_internal 44 ABSL_NAMESPACE_END 45 } // namespace absl 46 47 #endif // ABSL_RANDOM_INTERNAL_RANDEN_SLOW_H_ 48