libsodium_crypto_core_keccak1600 (libsodium v3.0.1)

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The Keccak-f[1600] permutation underlying SHA-3, SHAKE, and TurboSHAKE. This is a low-level primitive for building sponge and duplex constructions; prefer libsodium_crypto_xof_shake128, libsodium_crypto_xof_turboshake128, or their 256-bit variants for hashing.

The permutation acts on a 200-byte (1600-bit) state held in an opaque state/0. init/0 returns the all-zero state, xor_bytes/3 XORs bytes into it at an offset, extract_bytes/3 reads bytes from it, permute_24/1 applies the full 24-round Keccak-f[1600], and permute_12/1 applies the 12-round Keccak-p[1600,12] used by TurboSHAKE. Offsets and lengths must satisfy Offset + Length =< 200.

States are immutable values: every operation returns a new state and leaves its argument unchanged.

State0 = libsodium_crypto_core_keccak1600:init(),
State1 = libsodium_crypto_core_keccak1600:xor_bytes(State0, <<"abc", 16#1F>>, 0),
State2 = libsodium_crypto_core_keccak1600:xor_bytes(State1, <<16#80>>, 167),
State3 = libsodium_crypto_core_keccak1600:permute_24(State2),
Out = libsodium_crypto_core_keccak1600:extract_bytes(State3, 0, 32),
Out = crypto:hash_xof(shake128, <<"abc">>, 256).

Summary

Types

state()

An opaque native crypto_core_keccak1600_state.

Functions

extract_bytes(State, Offset, Length)

Return Length bytes of State starting at byte Offset. Offset + Length must not exceed 200.

init()

Return the all-zero permutation state.

permute_12(State)

Apply the 12-round Keccak-p[1600,12] permutation used by TurboSHAKE to State and return the new state.

permute_24(State)

Apply the 24-round Keccak-f[1600] permutation to State and return the new state.

statebytes()

Return crypto_core_keccak1600_statebytes(), in bytes.

xor_bytes(State, Bytes, Offset)

XOR Bytes into State starting at byte Offset and return the new state. Offset + byte_size(Bytes) must not exceed 200.

Types

state()

-type state() :: libsodium_nif:crypto_core_keccak1600_state().

An opaque native crypto_core_keccak1600_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

extract_bytes(State, Offset, Length)

-spec extract_bytes(State, Offset, Length) -> Result
                       when
                           State :: state(),
                           Offset :: non_neg_integer(),
                           Length :: non_neg_integer(),
                           Result :: binary().

Return Length bytes of State starting at byte Offset. Offset + Length must not exceed 200.

init()

-spec init() -> Result when Result :: state().

Return the all-zero permutation state.

permute_12(State)

-spec permute_12(State) -> Result when State :: state(), Result :: state().

Apply the 12-round Keccak-p[1600,12] permutation used by TurboSHAKE to State and return the new state.

permute_24(State)

-spec permute_24(State) -> Result when State :: state(), Result :: state().

Apply the 24-round Keccak-f[1600] permutation to State and return the new state.

statebytes()

-spec statebytes() -> Result when Result :: 224.

Return crypto_core_keccak1600_statebytes(), in bytes.

xor_bytes(State, Bytes, Offset)

-spec xor_bytes(State, Bytes, Offset) -> Result
                   when
                       State :: state(),
                       Bytes :: binary(),
                       Offset :: non_neg_integer(),
                       Result :: state().

XOR Bytes into State starting at byte Offset and return the new state. Offset + byte_size(Bytes) must not exceed 200.