silk.crypto.sha3.

When to use#

Use these types when a protocol names SHA-3. For a general cryptographic hash, silk.crypto.sha2 is more common. Use silk.collections.hash for the keys of a hash map.

Details#

Sha3_224, Sha3_256, Sha3_384, and Sha3_512 return 28, 32, 48, and 64 bytes. Each type has the same functions: hash returns the digest of one slice, and make, update, and finish hash a message that arrives in parts. The states are fixed-size values and nothing allocates. There is no length limit.

Gotchas#

SHA-3 is not Keccak-256 as Ethereum uses it: the padding is different, so the digests are different. This module has no SHAKE or other extendable-output function.

Examples#

Hash a message in one call and in parts#

import silk.crypto.sha3 { Sha3_256 }

pub fn main() -> i32 {
  let oneShot = Sha3_256.hash(b"abc")
  let mut state = Sha3_256.make()
  state.update(b"a")
  state.update(b"bc")
  let streamed = state.finish()

  // SHA3-256("abc") is 3a985da7...1532.
  if oneShot[0] != 0x3a || oneShot[31] != 0x32 || streamed[31] != oneShot[31] {
    return 1
  }
  return 0
}

Import as Sha3_256 with import silk.crypto.sha3 { Sha3_256 }.

Public declarations: 4.

Sha3_224#

pub struct Sha3_224

A streaming SHA3-224 state that returns a 28-byte digest.

Call Sha3_224.update for each part of the message, then Sha3_224.finish. Use Sha3_224.hash when the full message is in one slice. The state is a fixed-size value and does not allocate.

Gotchas#

It is not Keccak-256 as Ethereum uses it: the padding is different, so the digests are different.

Implementation Sha3_224#

impl Sha3_224

Associated function make#

pub fn make() -> Sha3_224

Returns a SHA3-224 state for an empty message.

Method update#

pub fn update(self: &mut Self, bytes: &[u8]) -> ()

Adds bytes to the end of the message. Any split of the message into parts gives the same digest. An empty slice changes nothing.

Method finish#

pub fn finish(self: Self) -> [u8; 28]

Returns the 28-byte SHA3-224 digest of the message and consumes the state.

Associated function hash#

pub fn hash(bytes: &[u8]) -> [u8; 28]

Returns the 28-byte SHA3-224 digest of bytes.

Sha3_256#

pub struct Sha3_256

A streaming SHA3-256 state that returns a 32-byte digest.

Call Sha3_256.update for each part of the message, then Sha3_256.finish. Use Sha3_256.hash when the full message is in one slice. The state is a fixed-size value and does not allocate.

Gotchas#

It is not Keccak-256 as Ethereum uses it: the padding is different, so the digests are different.

Implementation Sha3_256#

impl Sha3_256

Associated function make#

pub fn make() -> Sha3_256

Returns a SHA3-256 state for an empty message.

Method update#

pub fn update(self: &mut Self, bytes: &[u8]) -> ()

Adds bytes to the end of the message. Any split of the message into parts gives the same digest. An empty slice changes nothing.

Method finish#

pub fn finish(self: Self) -> [u8; 32]

Returns the 32-byte SHA3-256 digest of the message and consumes the state.

Associated function hash#

pub fn hash(bytes: &[u8]) -> [u8; 32]

Returns the 32-byte SHA3-256 digest of bytes.

Sha3_384#

pub struct Sha3_384

A streaming SHA3-384 state that returns a 48-byte digest.

Call Sha3_384.update for each part of the message, then Sha3_384.finish. Use Sha3_384.hash when the full message is in one slice. The state is a fixed-size value and does not allocate.

Gotchas#

It is not Keccak-256 as Ethereum uses it: the padding is different, so the digests are different.

Implementation Sha3_384#

impl Sha3_384

Associated function make#

pub fn make() -> Sha3_384

Returns a SHA3-384 state for an empty message.

Method update#

pub fn update(self: &mut Self, bytes: &[u8]) -> ()

Adds bytes to the end of the message. Any split of the message into parts gives the same digest. An empty slice changes nothing.

Method finish#

pub fn finish(self: Self) -> [u8; 48]

Returns the 48-byte SHA3-384 digest of the message and consumes the state.

Associated function hash#

pub fn hash(bytes: &[u8]) -> [u8; 48]

Returns the 48-byte SHA3-384 digest of bytes.

Sha3_512#

pub struct Sha3_512

A streaming SHA3-512 state that returns a 64-byte digest.

Call Sha3_512.update for each part of the message, then Sha3_512.finish. Use Sha3_512.hash when the full message is in one slice. The state is a fixed-size value and does not allocate.

Gotchas#

It is not Keccak-256 as Ethereum uses it: the padding is different, so the digests are different.

Implementation Sha3_512#

impl Sha3_512

Associated function make#

pub fn make() -> Sha3_512

Returns a SHA3-512 state for an empty message.

Method update#

pub fn update(self: &mut Self, bytes: &[u8]) -> ()

Adds bytes to the end of the message. Any split of the message into parts gives the same digest. An empty slice changes nothing.

Method finish#

pub fn finish(self: Self) -> [u8; 64]

Returns the 64-byte SHA3-512 digest of the message and consumes the state.

Associated function hash#

pub fn hash(bytes: &[u8]) -> [u8; 64]

Returns the 64-byte SHA3-512 digest of bytes.

Category: Cryptography.

Profiles: aarch64-apple-darwin, aarch64-unknown-linux-gnu, aarch64-unknown-linux-gnu-no-libc, x86_64-unknown-linux-gnu, x86_64-unknown-linux-gnu-no-libc, wasm32-unknown-unknown, wasm32-wasip1, wasm32-wasip2.