esphome::sha256::SHA256 Class Reference

SHA256 hash implementation. More...

#include <sha256.h>

Inheritance diagram for esphome::sha256::SHA256:

Public Member Functions
	SHA256 ()=default
	~SHA256 () override
void	init () override
void	add (const uint8_t *data, size_t len) override
void	add (const std::string &data)
void	calculate () override
size_t	get_size () const override
	Get the size of the hash in bytes (32 for SHA256)
void	add (const char *data, size_t len)
Public Member Functions inherited from esphome::HashBase
virtual	~HashBase ()=default
void	add (const char *data, size_t len)
void	get_bytes (uint8_t *output)
	Retrieve the hash as bytes.
void	get_hex (char *output)
	Retrieve the hash as hex characters. Output buffer must hold get_size() * 2 + 1 bytes.
bool	equals_bytes (const uint8_t *expected)
	Compare the hash against a provided byte-encoded hash.
bool	equals_hex (const char *expected)
	Compare the hash against a provided hex-encoded hash.

Protected Attributes
mbedtls_sha256_context	ctx_ {}
br_sha256_context	ctx_ {}
bool	calculated_ {false}
EVP_MD_CTX *	ctx_ {nullptr}
Protected Attributes inherited from esphome::HashBase
uint8_t	digest_ [32]

Detailed Description

SHA256 hash implementation.

CRITICAL for ESP32 variants (except original) with IDF 5.5.x hardware SHA acceleration:

1. The object MUST stay in the same stack frame (no passing to other functions)
2. NO Variable Length Arrays (VLAs) in the same function

Note: Alignment is handled automatically via the HashBase::digest_ member.

Example usage: sha256::SHA256 hasher; hasher.init(); hasher.add(data, len); hasher.calculate();

Definition at line 38 of file sha256.h.

Constructor & Destructor Documentation

SHA256()

esphome::sha256::SHA256::SHA256 ( )

default

~SHA256()

esphome::sha256::SHA256::~SHA256 ( )

overridedefault

Definition at line 47 of file sha256.cpp.

Member Function Documentation

add() [1/3]

void esphome::HashBase::add ( const char * data, size_t len )

inline

Definition at line 20 of file hash_base.h.

add() [2/3]

void esphome::sha256::SHA256::add ( const std::string & data )

inline

Definition at line 46 of file sha256.h.

add() [3/3]

void esphome::sha256::SHA256::add ( const uint8_t * data, size_t len )

overridevirtual

Implements esphome::HashBase.

Definition at line 54 of file sha256.cpp.

calculate()

void esphome::sha256::SHA256::calculate ( )

overridevirtual

Implements esphome::HashBase.

Definition at line 56 of file sha256.cpp.

get_size()

size_t esphome::sha256::SHA256::get_size ( ) const

inlineoverridevirtual

Get the size of the hash in bytes (32 for SHA256)

Implements esphome::HashBase.

Definition at line 51 of file sha256.h.

init()

void esphome::sha256::SHA256::init ( )

overridevirtual

Implements esphome::HashBase.

Definition at line 49 of file sha256.cpp.

Field Documentation

calculated_

bool esphome::sha256::SHA256::calculated_ {false}

protected

Definition at line 60 of file sha256.h.

ctx_ [1/3]

mbedtls_sha256_context esphome::sha256::SHA256::ctx_ {}

protected

Definition at line 57 of file sha256.h.

ctx_ [2/3]

br_sha256_context esphome::sha256::SHA256::ctx_ {}

protected

Definition at line 59 of file sha256.h.

ctx_ [3/3]

EVP_MD_CTX* esphome::sha256::SHA256::ctx_ {nullptr}

protected

Definition at line 62 of file sha256.h.

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The documentation for this class was generated from the following files:

• esphome/components/sha256/sha256.h
• esphome/components/sha256/sha256.cpp