libsodium_crypto_auth_hmacsha512256 (libsodium v3.0.1)
View SourceSecret-key message authentication with HMAC-SHA-512-256: HMAC-SHA-512
truncated to 256 bits. This is the construction used by
libsodium_crypto_auth.
The one-shot functions take a keybytes/0 byte key and produce
bytes/0 byte tags. The streaming functions thread an opaque
state/0 through init/1, update/2, and
final/1; each call returns a new state and leaves its argument
unchanged. Updates over large inputs yield to other processes between
chunks. Unlike the one-shot functions, init/1 accepts a key of any
length, as HMAC does.
verify/3 compares tags in constant time.
Key = libsodium_crypto_auth_hmacsha512256:keygen(),
Tag = libsodium_crypto_auth_hmacsha512256:crypto_auth_hmacsha512256(<<"message">>, Key),
0 = libsodium_crypto_auth_hmacsha512256:verify(Tag, <<"message">>, Key),
-1 = libsodium_crypto_auth_hmacsha512256:verify(Tag, <<"forged">>, Key),
State0 = libsodium_crypto_auth_hmacsha512256:init(Key),
State1 = libsodium_crypto_auth_hmacsha512256:update(State0, <<"mess">>),
State2 = libsodium_crypto_auth_hmacsha512256:update(State1, <<"age">>),
Tag = libsodium_crypto_auth_hmacsha512256:final(State2).Summary
Types
A crypto_auth_hmacsha512256_BYTES (32-byte) binary.
A crypto_auth_hmacsha512256_KEYBYTES (32-byte) binary.
A crypto_auth_hmacsha512256_BYTES (32-byte) binary.
An opaque native crypto_auth_hmacsha512256_state.
Functions
Return crypto_auth_hmacsha512256_bytes(), in bytes.
Compute the bytes/0 byte authentication tag of In under the keybytes/0 byte key K.
Finish the streaming authenticator in State, returning a bytes/0 byte tag.
Start a streaming authenticator keyed with Key, which may be of any
length, and return its state.
Return crypto_auth_hmacsha512256_keybytes(), in bytes.
Generate a random keybytes/0 byte key.
Return crypto_auth_hmacsha512256_statebytes(), in bytes.
Absorb In into State and return the updated state.
Check in constant time that H is the tag of In under the key K.
Returns 0 when it is valid and -1 otherwise.
Types
-type h() :: <<_:256>>.
A crypto_auth_hmacsha512256_BYTES (32-byte) binary.
-type k() :: <<_:256>>.
A crypto_auth_hmacsha512256_KEYBYTES (32-byte) binary.
-type out() :: <<_:256>>.
A crypto_auth_hmacsha512256_BYTES (32-byte) binary.
-type state() :: libsodium_nif:crypto_auth_hmacsha512256_state().
An opaque native crypto_auth_hmacsha512256_state.
Operations never modify a state: each returns a new one, so earlier states remain valid and can be reused or shared between processes. States cannot be serialized; they exist only within the running VM.
Functions
-spec bytes() -> Result when Result :: 32.
Return crypto_auth_hmacsha512256_bytes(), in bytes.
-spec crypto_auth_hmacsha512256(In, K) -> Result when In :: binary(), K :: k(), Result :: out() | -1.
Compute the bytes/0 byte authentication tag of In under the keybytes/0 byte key K.
Finish the streaming authenticator in State, returning a bytes/0 byte tag.
Start a streaming authenticator keyed with Key, which may be of any
length, and return its state.
-spec keybytes() -> Result when Result :: 32.
Return crypto_auth_hmacsha512256_keybytes(), in bytes.
-spec keygen() -> Result when Result :: k().
Generate a random keybytes/0 byte key.
-spec statebytes() -> Result when Result :: 416.
Return crypto_auth_hmacsha512256_statebytes(), in bytes.
Absorb In into State and return the updated state.
Check in constant time that H is the tag of In under the key K.
Returns 0 when it is valid and -1 otherwise.