diff options
Diffstat (limited to 'comm/third_party/botan/src/lib/rng/chacha_rng/chacha_rng.cpp')
-rw-r--r-- | comm/third_party/botan/src/lib/rng/chacha_rng/chacha_rng.cpp | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/rng/chacha_rng/chacha_rng.cpp b/comm/third_party/botan/src/lib/rng/chacha_rng/chacha_rng.cpp new file mode 100644 index 0000000000..3dc69ec1b8 --- /dev/null +++ b/comm/third_party/botan/src/lib/rng/chacha_rng/chacha_rng.cpp @@ -0,0 +1,87 @@ +/* +* ChaCha_RNG +* (C) 2017 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/chacha_rng.h> + +namespace Botan { + +ChaCha_RNG::ChaCha_RNG() : Stateful_RNG() + { + m_hmac = MessageAuthenticationCode::create_or_throw("HMAC(SHA-256)"); + m_chacha = StreamCipher::create_or_throw("ChaCha(20)"); + clear(); + } + +ChaCha_RNG::ChaCha_RNG(const secure_vector<uint8_t>& seed) : Stateful_RNG() + { + m_hmac = MessageAuthenticationCode::create_or_throw("HMAC(SHA-256)"); + m_chacha = StreamCipher::create_or_throw("ChaCha(20)"); + clear(); + add_entropy(seed.data(), seed.size()); + } + +ChaCha_RNG::ChaCha_RNG(RandomNumberGenerator& underlying_rng, + size_t reseed_interval) : + Stateful_RNG(underlying_rng, reseed_interval) + { + m_hmac = MessageAuthenticationCode::create_or_throw("HMAC(SHA-256)"); + m_chacha = StreamCipher::create_or_throw("ChaCha(20)"); + clear(); + } + +ChaCha_RNG::ChaCha_RNG(RandomNumberGenerator& underlying_rng, + Entropy_Sources& entropy_sources, + size_t reseed_interval) : + Stateful_RNG(underlying_rng, entropy_sources, reseed_interval) + { + m_hmac = MessageAuthenticationCode::create_or_throw("HMAC(SHA-256)"); + m_chacha = StreamCipher::create_or_throw("ChaCha(20)"); + clear(); + } + +ChaCha_RNG::ChaCha_RNG(Entropy_Sources& entropy_sources, + size_t reseed_interval) : + Stateful_RNG(entropy_sources, reseed_interval) + { + m_hmac = MessageAuthenticationCode::create_or_throw("HMAC(SHA-256)"); + m_chacha = StreamCipher::create_or_throw("ChaCha(20)"); + clear(); + } + +void ChaCha_RNG::clear_state() + { + m_hmac->set_key(std::vector<uint8_t>(m_hmac->output_length(), 0x00)); + m_chacha->set_key(m_hmac->final()); + } + +void ChaCha_RNG::generate_output(uint8_t output[], size_t output_len, + const uint8_t input[], size_t input_len) + { + if(input_len > 0) + { + update(input, input_len); + } + + m_chacha->write_keystream(output, output_len); + } + +void ChaCha_RNG::update(const uint8_t input[], size_t input_len) + { + m_hmac->update(input, input_len); + m_chacha->set_key(m_hmac->final()); + + secure_vector<uint8_t> mac_key(m_hmac->output_length()); + m_chacha->write_keystream(mac_key.data(), mac_key.size()); + m_hmac->set_key(mac_key); + } + +size_t ChaCha_RNG::security_level() const + { + return 256; + } + +} |