Botan 3.5.0
Crypto and TLS for C&
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#include <chacha_rng.h>
Public Member Functions | |
bool | accepts_input () const final |
void | add_entropy (const uint8_t input[], size_t length) |
void | add_entropy (std::span< const uint8_t > input) |
template<typename T > requires std::is_standard_layout<T>::value && std::is_trivial<T>::value | |
void | add_entropy_T (const T &t) |
ChaCha_RNG () | |
ChaCha_RNG (Entropy_Sources &entropy_sources, size_t reseed_interval=BOTAN_RNG_DEFAULT_RESEED_INTERVAL) | |
ChaCha_RNG (RandomNumberGenerator &underlying_rng, Entropy_Sources &entropy_sources, size_t reseed_interval=BOTAN_RNG_DEFAULT_RESEED_INTERVAL) | |
ChaCha_RNG (RandomNumberGenerator &underlying_rng, size_t reseed_interval=BOTAN_RNG_DEFAULT_RESEED_INTERVAL) | |
ChaCha_RNG (std::span< const uint8_t > seed) | |
void | clear () final |
void | force_reseed () |
void | initialize_with (const uint8_t input[], size_t length) |
void | initialize_with (std::span< const uint8_t > input) |
bool | is_seeded () const final |
size_t | max_number_of_bytes_per_request () const override |
std::string | name () const override |
uint8_t | next_byte () |
uint8_t | next_nonzero_byte () |
template<size_t bytes> | |
std::array< uint8_t, bytes > | random_array () |
template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>> requires std::default_initializable<T> | |
T | random_vec (size_t bytes) |
void | random_vec (std::span< uint8_t > v) |
template<concepts::resizable_byte_buffer T> | |
void | random_vec (T &v, size_t bytes) |
void | randomize (std::span< uint8_t > output) |
void | randomize (uint8_t output[], size_t length) |
void | randomize_with_input (std::span< uint8_t > output, std::span< const uint8_t > input) |
void | randomize_with_input (uint8_t output[], size_t output_len, const uint8_t input[], size_t input_len) |
void | randomize_with_ts_input (std::span< uint8_t > output) |
void | randomize_with_ts_input (uint8_t output[], size_t output_len) |
size_t | reseed (Entropy_Sources &srcs, size_t poll_bits=BOTAN_RNG_RESEED_POLL_BITS, std::chrono::milliseconds poll_timeout=BOTAN_RNG_RESEED_DEFAULT_TIMEOUT) override |
void | reseed_from_rng (RandomNumberGenerator &rng, size_t poll_bits=BOTAN_RNG_RESEED_POLL_BITS) final |
size_t | reseed_interval () const |
size_t | security_level () const override |
Protected Member Functions | |
void | reseed_check () |
ChaCha_RNG is a very fast but completely ad-hoc RNG created by creating a 256-bit random value and using it as a key for ChaCha20.
The RNG maintains two 256-bit keys, one for HMAC_SHA256 (HK) and the other for ChaCha20 (CK). To compute a new key in response to reseeding request or add_entropy calls, ChaCha_RNG computes CK' = HMAC_SHA256(HK, input_material) Then a new HK' is computed by running ChaCha20 with the new key to output 32 bytes: HK' = ChaCha20(CK')
Now output can be produced by continuing to produce output with ChaCha20 under CK'
The first HK (before seeding occurs) is taken as the all zero value.
Definition at line 40 of file chacha_rng.h.
Botan::ChaCha_RNG::ChaCha_RNG | ( | ) |
Automatic reseeding is disabled completely, as it has no access to any source for seed material.
If a fork is detected, the RNG will be unable to reseed itself in response. In this case, an exception will be thrown rather than generating duplicated output.
Definition at line 12 of file chacha_rng.cpp.
References Botan::Stateful_RNG::clear(), Botan::MessageAuthenticationCode::create_or_throw(), and Botan::StreamCipher::create_or_throw().
Botan::ChaCha_RNG::ChaCha_RNG | ( | std::span< const uint8_t > | seed | ) |
Provide an initial seed to the RNG, without providing an underlying RNG or entropy source. Automatic reseeding is disabled completely, as it has no access to any source for seed material.
If a fork is detected, the RNG will be unable to reseed itself in response. In this case, an exception will be thrown rather than generating duplicated output.
seed | the seed material, should be at least 256 bits |
Definition at line 18 of file chacha_rng.cpp.
References Botan::RandomNumberGenerator::add_entropy(), Botan::Stateful_RNG::clear(), Botan::MessageAuthenticationCode::create_or_throw(), and Botan::StreamCipher::create_or_throw().
Botan::ChaCha_RNG::ChaCha_RNG | ( | RandomNumberGenerator & | underlying_rng, |
size_t | reseed_interval = BOTAN_RNG_DEFAULT_RESEED_INTERVAL ) |
Automatic reseeding from underlying_rng
will take place after reseed_interval
many requests or after a fork was detected.
underlying_rng | is a reference to some RNG which will be used to perform the periodic reseeding |
reseed_interval | specifies a limit of how many times the RNG will be called before automatic reseeding is performed |
Definition at line 25 of file chacha_rng.cpp.
References Botan::Stateful_RNG::clear(), Botan::MessageAuthenticationCode::create_or_throw(), and Botan::StreamCipher::create_or_throw().
Botan::ChaCha_RNG::ChaCha_RNG | ( | Entropy_Sources & | entropy_sources, |
size_t | reseed_interval = BOTAN_RNG_DEFAULT_RESEED_INTERVAL ) |
Automatic reseeding from entropy_sources
will take place after reseed_interval
many requests or after a fork was detected.
entropy_sources | will be polled to perform reseeding periodically |
reseed_interval | specifies a limit of how many times the RNG will be called before automatic reseeding is performed. |
Definition at line 41 of file chacha_rng.cpp.
References Botan::Stateful_RNG::clear(), Botan::MessageAuthenticationCode::create_or_throw(), and Botan::StreamCipher::create_or_throw().
Botan::ChaCha_RNG::ChaCha_RNG | ( | RandomNumberGenerator & | underlying_rng, |
Entropy_Sources & | entropy_sources, | ||
size_t | reseed_interval = BOTAN_RNG_DEFAULT_RESEED_INTERVAL ) |
Automatic reseeding from underlying_rng
and entropy_sources
will take place after reseed_interval
many requests or after a fork was detected.
underlying_rng | is a reference to some RNG which will be used to perform the periodic reseeding |
entropy_sources | will be polled to perform reseeding periodically |
reseed_interval | specifies a limit of how many times the RNG will be called before automatic reseeding is performed. |
Definition at line 32 of file chacha_rng.cpp.
References Botan::Stateful_RNG::clear(), Botan::MessageAuthenticationCode::create_or_throw(), and Botan::StreamCipher::create_or_throw().
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inlinefinalvirtualinherited |
Returns false if it is known that this RNG object is not able to accept externally provided inputs (via add_entropy, randomize_with_input, etc). In this case, any such provided inputs are ignored.
If this function returns true, then inputs may or may not be accepted.
Implements Botan::RandomNumberGenerator.
Definition at line 71 of file stateful_rng.h.
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inlineinherited |
Definition at line 77 of file rng.h.
References Botan::RandomNumberGenerator::add_entropy().
Referenced by Botan::RandomNumberGenerator::add_entropy().
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inlineinherited |
Incorporate some additional data into the RNG state. For example adding nonces or timestamps from a peer's protocol message can help hedge against VM state rollback attacks. A few RNG types do not accept any externally provided input, in which case this function is a no-op.
input | a byte array containing the entropy to be added |
Exception | may throw if the RNG accepts input, but adding the entropy failed. |
Definition at line 75 of file rng.h.
Referenced by ChaCha_RNG(), Botan::Stateful_RNG::initialize_with(), Botan::Getentropy::poll(), Botan::Intel_Rdseed::poll(), and Botan::RandomNumberGenerator::reseed_from_rng().
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inlineinherited |
Incorporate some additional data into the RNG state.
Definition at line 84 of file rng.h.
References T.
Referenced by Botan::Win32_EntropySource::poll().
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finalvirtualinherited |
Clear all internally held values of this RNG
Implements Botan::RandomNumberGenerator.
Definition at line 14 of file stateful_rng.cpp.
References Botan::Stateful_RNG::clear_state(), and Botan::lock().
Referenced by ChaCha_RNG(), ChaCha_RNG(), ChaCha_RNG(), ChaCha_RNG(), ChaCha_RNG(), Botan::HMAC_DRBG::HMAC_DRBG(), Botan::HMAC_DRBG::HMAC_DRBG(), Botan::HMAC_DRBG::HMAC_DRBG(), Botan::HMAC_DRBG::HMAC_DRBG(), Botan::HMAC_DRBG::HMAC_DRBG(), and Botan::Stateful_RNG::initialize_with().
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inherited |
Mark state as requiring a reseed on next use
Definition at line 21 of file stateful_rng.cpp.
References Botan::lock().
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inlineinherited |
Definition at line 67 of file stateful_rng.h.
References Botan::Stateful_RNG::initialize_with().
Referenced by Botan::Stateful_RNG::initialize_with().
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inherited |
Consume this input and mark the RNG as initialized regardless of the length of the input or the current seeded state of the RNG.
Definition at line 31 of file stateful_rng.cpp.
References Botan::RandomNumberGenerator::add_entropy(), Botan::Stateful_RNG::clear(), and Botan::lock().
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finalvirtualinherited |
Check whether this RNG is seeded.
Implements Botan::RandomNumberGenerator.
Definition at line 26 of file stateful_rng.cpp.
References Botan::lock().
Referenced by Botan::Stateful_RNG::reseed_check().
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inlineoverridevirtual |
Some DRBGs have a notion of the maximum number of bytes per request. Longer requests (to randomize) will be treated as multiple requests, and may initiate reseeding multiple times, depending on the values of max_number_of_bytes_per_request and reseed_interval(). This function returns zero if the RNG in question does not have such a notion.
Implements Botan::Stateful_RNG.
Definition at line 106 of file chacha_rng.h.
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inlineoverridevirtual |
Implements Botan::RandomNumberGenerator.
Definition at line 102 of file chacha_rng.h.
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inlineinherited |
Return a random byte
PRNG_Unseeded | if the RNG fails because it has not enough entropy |
Exception | if the RNG fails |
Definition at line 227 of file rng.h.
Referenced by Botan::random_prime().
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inlineinherited |
PRNG_Unseeded | if the RNG fails because it has not enough entropy |
Exception | if the RNG fails |
Definition at line 238 of file rng.h.
Referenced by Botan::EME_PKCS1v15::pad().
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inlineinherited |
Create a std::array of bytes
random bytes
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inlineinherited |
Create some byte container type and fill it with some random bytes
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T | the desired byte container type (e.g std::vector<uint8_t>) |
bytes | number of random bytes to initialize the container with |
bytes
random bytes Exception | if RNG or memory allocation fails |
Definition at line 205 of file rng.h.
References T.
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inlineinherited |
Fill a given byte container with bytes
random bytes
v | the container to be filled with bytes random bytes |
Exception | if RNG fails |
Definition at line 179 of file rng.h.
Referenced by Botan::TLS::Client_Key_Exchange::Client_Key_Exchange(), Botan::TLS::Client_Key_Exchange::Client_Key_Exchange(), Botan::PK_Decryptor::decrypt_or_random(), Botan::Dilithium_PrivateKey::Dilithium_PrivateKey(), Botan::Ed25519_PrivateKey::Ed25519_PrivateKey(), Botan::Kyber_KEM_Encryptor::encapsulate(), Botan::TLS::Session::encrypt(), Botan::KeyPair::encryption_consistency_check(), Botan::FrodoKEM_PrivateKey::FrodoKEM_PrivateKey(), Botan::generate_bcrypt(), Botan::HSS_LMS_PrivateKeyInternal::HSS_LMS_PrivateKeyInternal(), Botan::Kyber_PrivateKey::Kyber_PrivateKey(), Botan::TLS::make_hello_random(), Botan::OctetString::OctetString(), Botan::BigInt::randomize(), Botan::RandomNumberGenerator::reseed_from_rng(), Botan::SphincsPlus_PrivateKey::SphincsPlus_PrivateKey(), and Botan::X25519_PrivateKey::X25519_PrivateKey().
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inlineinherited |
Resize a given byte container to bytes
and fill it with random bytes
T | the desired byte container type (e.g std::vector<uint8_t>) |
v | the container to be filled with bytes random bytes |
bytes | number of random bytes to initialize the container with |
Exception | if RNG or memory allocation fails |
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inlineinherited |
Randomize a byte array.
May block shortly if e.g. the RNG is not yet initialized or a retry because of insufficient entropy is needed.
output | the byte array to hold the random output. |
PRNG_Unseeded | if the RNG fails because it has not enough entropy |
Exception | if the RNG fails |
Definition at line 52 of file rng.h.
Referenced by Botan::TLS::Connection_Cipher_State::aead_nonce(), Botan::argon2_generate_pwhash(), Botan::BlindedScalarBits< C, WindowBits >::BlindedScalarBits(), botan_system_rng_get(), Botan::Ed448_PrivateKey::Ed448_PrivateKey(), Botan::CryptoBox::encrypt(), Botan::generate_dsa_primes(), Botan::generate_passhash9(), Botan::Roughtime::Nonce::Nonce(), Botan::IntMod< Rep >::random(), Botan::random_gf2m(), Botan::McEliece_PublicKey::random_plaintext_element(), Botan::random_prime(), Botan::Sodium::randombytes_buf(), Botan::RandomNumberGenerator::randomize_with_ts_input(), Botan::KeyPair::signature_consistency_check(), Botan::RTSS_Share::split(), Botan::UUID::UUID(), and Botan::X448_PrivateKey::X448_PrivateKey().
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inlineinherited |
Definition at line 54 of file rng.h.
References Botan::RandomNumberGenerator::randomize().
Referenced by Botan::RandomNumberGenerator::randomize().
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inlineinherited |
Incorporate entropy into the RNG state then produce output. Some RNG types implement this using a single operation, default calls add_entropy + randomize in sequence.
Use this to further bind the outputs to your current process/protocol state. For instance if generating a new key for use in a session, include a session ID or other such value. See NIST SP 800-90 A, B, C series for more ideas.
output | buffer to hold the random output |
input | entropy buffer to incorporate |
PRNG_Unseeded | if the RNG fails because it has not enough entropy |
Exception | if the RNG fails |
Exception | may throw if the RNG accepts input, but adding the entropy failed. |
Definition at line 104 of file rng.h.
Referenced by Botan::System_RNG::fill_bytes_with_input().
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inlineinherited |
Definition at line 108 of file rng.h.
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inherited |
This calls randomize_with_input
using some timestamps as extra input.
For a stateful RNG using non-random but potentially unique data the extra input can help protect against problems with fork, VM state rollback, or other cases where somehow an RNG state is duplicated. If both of the duplicated RNG states later incorporate a timestamp (and the timestamps don't themselves repeat), their outputs will diverge.
output | buffer to hold the random output |
PRNG_Unseeded | if the RNG fails because it has not enough entropy |
Exception | if the RNG fails |
Exception | may throw if the RNG accepts input, but adding the entropy failed. |
Definition at line 21 of file rng.cpp.
References Botan::RandomNumberGenerator::accepts_input(), Botan::RandomNumberGenerator::fill_bytes_with_input(), Botan::OS::get_high_resolution_clock(), Botan::OS::get_process_id(), Botan::OS::get_system_timestamp_ns(), Botan::RandomNumberGenerator::randomize(), Botan::store_le(), and Botan::system_rng().
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inlineinherited |
Definition at line 128 of file rng.h.
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overridevirtualinherited |
Poll provided sources for up to poll_bits bits of entropy or until the timeout expires. Returns estimate of the number of bits collected.
Reimplemented from Botan::RandomNumberGenerator.
Definition at line 77 of file stateful_rng.cpp.
References Botan::lock(), Botan::RandomNumberGenerator::reseed(), and Botan::Stateful_RNG::security_level().
Referenced by Botan::Stateful_RNG::reseed_check().
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protectedinherited |
Definition at line 104 of file stateful_rng.cpp.
References BOTAN_ASSERT, Botan::OS::get_process_id(), Botan::Stateful_RNG::is_seeded(), Botan::RandomNumberGenerator::name(), Botan::Stateful_RNG::reseed(), Botan::Stateful_RNG::reseed_from_rng(), and Botan::Stateful_RNG::security_level().
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finalvirtualinherited |
Reseed by reading specified bits from the RNG
Sets the seeded state to true if enough entropy was added.
Exception | if RNG accepts input but reseeding failed. |
Reimplemented from Botan::RandomNumberGenerator.
Definition at line 89 of file stateful_rng.cpp.
References Botan::lock(), Botan::RandomNumberGenerator::reseed_from_rng(), and Botan::Stateful_RNG::security_level().
Referenced by Botan::Stateful_RNG::reseed_check().
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inlineinherited |
Definition at line 106 of file stateful_rng.h.
Referenced by Botan::HMAC_DRBG::HMAC_DRBG(), Botan::HMAC_DRBG::HMAC_DRBG(), and Botan::HMAC_DRBG::HMAC_DRBG().
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overridevirtual |
Implements Botan::Stateful_RNG.
Definition at line 70 of file chacha_rng.cpp.