1 /* 2 * Salsa20 / XSalsa20 3 * (C) 1999-2010 Jack Lloyd 4 * 5 * Botan is released under the Simplified BSD License (see license.txt) 6 */ 7 8 #ifndef BOTAN_SALSA20_H_ 9 #define BOTAN_SALSA20_H_ 10 11 #include <botan/stream_cipher.h> 12 13 BOTAN_FUTURE_INTERNAL_HEADER(salsa20.h) 14 15 namespace Botan { 16 17 /** 18 * DJB's Salsa20 (and XSalsa20) 19 */ 20 class BOTAN_PUBLIC_API(2,0) Salsa20 final : public StreamCipher 21 { 22 public: 23 void cipher(const uint8_t in[], uint8_t out[], size_t length) override; 24 25 void set_iv(const uint8_t iv[], size_t iv_len) override; 26 27 bool valid_iv_length(size_t iv_len) const override; 28 29 size_t default_iv_length() const override; 30 31 Key_Length_Specification key_spec() const override; 32 33 void clear() override; 34 std::string name() const override; 35 StreamCipher* clone() const override; 36 37 static void salsa_core(uint8_t output[64], const uint32_t input[16], size_t rounds); 38 static void hsalsa20(uint32_t output[8], const uint32_t input[16]); 39 40 void seek(uint64_t offset) override; 41 private: 42 void key_schedule(const uint8_t key[], size_t key_len) override; 43 44 void initialize_state(); 45 46 secure_vector<uint32_t> m_key; 47 secure_vector<uint32_t> m_state; 48 secure_vector<uint8_t> m_buffer; 49 size_t m_position = 0; 50 }; 51 52 } 53 54 #endif 55