crypto::cipher::gcm_t Class Reference

AES-GCM cipher helper that encrypts and authenticates payloads. More...

#include <src/crypto.h>

Inheritance diagram for crypto::cipher::gcm_t:

Collaboration diagram for crypto::cipher::gcm_t:

Public Member Functions
int	decrypt (const std::string_view &cipher, std::vector< std::uint8_t > &plaintext, aes_t *iv)
	Decrypt ciphertext into the supplied plaintext buffer.
int	encrypt (const std::string_view &plaintext, std::uint8_t *tag, std::uint8_t *ciphertext, aes_t *iv)
	Encrypts the plaintext using AES GCM mode.
int	encrypt (const std::string_view &plaintext, std::uint8_t *tagged_cipher, aes_t *iv)
	Encrypts the plaintext using AES GCM mode. length of cipher must be at least: round_to_pkcs7_padded(plaintext.size()) + crypto::cipher::tag_size.
	gcm_t (const crypto::aes_t &key, bool padding=true)
	Construct an AES-GCM cipher helper with key material and IV state.
	gcm_t (gcm_t &&) noexcept=default
	Construct an AES-GCM cipher helper with key material and IV state.
gcm_t &	operator= (gcm_t &&) noexcept=default
	Assign state from another instance while preserving ownership semantics.

Additional Inherited Members
Public Attributes inherited from crypto::cipher::cipher_t
cipher_ctx_t	decrypt_ctx
	Decrypt ctx.
cipher_ctx_t	encrypt_ctx
	Encrypt ctx.
aes_t	key
	AES key used by the cipher context.
bool	padding
	Enables block padding for the cipher.

Detailed Description

AES-GCM cipher helper that encrypts and authenticates payloads.

Constructor & Destructor Documentation

gcm_t()

crypto::cipher::gcm_t::gcm_t	(	const crypto::aes_t &	key,
		bool	padding = true )

Construct an AES-GCM cipher helper with key material and IV state.

Parameters

key	AES key material used to initialize the cipher.
padding	Whether the cipher should use block padding.

Member Function Documentation

decrypt()

int crypto::cipher::gcm_t::decrypt	(	const std::string_view &	cipher,
		std::vector< std::uint8_t > &	plaintext,
		aes_t *	iv )

Decrypt ciphertext into the supplied plaintext buffer.

Parameters

cipher	Ciphertext bytes to decrypt or output buffer for encryption.
plaintext	Plaintext bytes to encrypt.
iv	Initialization vector for the cipher operation.

Returns

Number of bytes written, signature bytes, or an error status depending on the overload.

encrypt() [1/2]

int crypto::cipher::gcm_t::encrypt	(	const std::string_view &	plaintext,
		std::uint8_t *	tag,
		std::uint8_t *	ciphertext,
		aes_t *	iv )

Encrypts the plaintext using AES GCM mode.

Parameters

plaintext	The plaintext data to be encrypted.
tag	The buffer where the GCM tag will be written.
ciphertext	The buffer where the resulting ciphertext will be written.
iv	The initialization vector to be used for the encryption.

Returns

The total length of the ciphertext and GCM tag. Returns -1 in case of an error.

This function encrypts the given plaintext using the AES key in GCM mode. The initialization vector (IV) is also provided. The function handles the creation and initialization of the encryption context, and manages the encryption process. The resulting ciphertext and the GCM tag are written into the tagged_cipher buffer.

encrypt() [2/2]

int crypto::cipher::gcm_t::encrypt	(	const std::string_view &	plaintext,
		std::uint8_t *	tagged_cipher,
		aes_t *	iv )

Encrypts the plaintext using AES GCM mode. length of cipher must be at least: round_to_pkcs7_padded(plaintext.size()) + crypto::cipher::tag_size.

Parameters

plaintext	The plaintext data to be encrypted.
tagged_cipher	The buffer where the resulting ciphertext and GCM tag will be written.
iv	The initialization vector to be used for the encryption.

Returns

The total length of the ciphertext and GCM tag written into tagged_cipher. Returns -1 in case of an error.

operator=()

gcm_t & crypto::cipher::gcm_t::operator= ( gcm_t && )

defaultnoexcept

Assign state from another instance while preserving ownership semantics.

Returns

Reference or value produced by the operator.

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

• src/crypto.h
• src/crypto.cpp