primitives.hpp File Reference

Noise cryptographic primitives (SHA-256, HMAC, HKDF, X25519, ChaCha20- Poly1305, base64). More...

#include <esphome/api/bytes.hpp>
#include <array>
#include <cstdint>
#include <string>

Include dependency graph for primitives.hpp:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Namespaces
namespace	esphome
namespace	esphome::api
namespace	esphome::api::noise

Typedefs
using	esphome::api::noise::Hash = std::array< std::uint8_t, hash_len >
using	esphome::api::noise::SymmetricKey = std::array< std::uint8_t, key_len >
using	esphome::api::noise::PublicKey = std::array< std::uint8_t, key_len >
using	esphome::api::noise::PrivateKey = std::array< std::uint8_t, key_len >

Functions
Hash	esphome::api::noise::sha256 (ByteView data)
	SHA-256 of data.
Hash	esphome::api::noise::hmac_sha256 (ByteView key, ByteView data)
	HMAC-SHA-256 with key over data.
void	esphome::api::noise::hkdf (const Hash &chaining_key, ByteView input_key_material, int num_outputs, Hash &o1, Hash &o2, Hash &o3)
	Noise HKDF: derive num_outputs (1..3) 32-byte values from chaining_key and input_key_material.
PublicKey	esphome::api::noise::x25519_base (const PrivateKey &private_key)
	X25519 public key for a private scalar.
SymmetricKey	esphome::api::noise::x25519 (const PrivateKey &private_key, const PublicKey &peer_public)
	X25519 shared secret. Throws EncryptionError on an all-zero (degenerate) result.
void	esphome::api::noise::generate_keypair (PrivateKey &private_key, PublicKey &public_key)
	Generate a fresh X25519 keypair from the system CSPRNG.
ByteBuffer	esphome::api::noise::aead_encrypt (const SymmetricKey &key, std::uint64_t nonce, ByteView ad, ByteView plaintext)
	AEAD ChaCha20-Poly1305 (IETF) encryption.
bool	esphome::api::noise::aead_decrypt (const SymmetricKey &key, std::uint64_t nonce, ByteView ad, ByteView ciphertext, ByteBuffer &out_plaintext)
	AEAD ChaCha20-Poly1305 (IETF) decryption. Returns false on auth failure.
bool	esphome::api::noise::base64_decode (const std::string &text, ByteBuffer &out)
	Decode standard base64. Returns false on malformed input.

Variables
constexpr std::size_t	esphome::api::noise::hash_len = 32
	SHA-256 digest / key size.
constexpr std::size_t	esphome::api::noise::key_len = 32
	Symmetric / DH key size.

Detailed Description

Noise cryptographic primitives (SHA-256, HMAC, HKDF, X25519, ChaCha20- Poly1305, base64).

The implementation (src/crypto/primitives.cpp) wraps vendored, public-domain reference code under src/crypto/detail/ plus the OS CSPRNG. Built only when ESPHOME_API_WITH_NOISE is on.