Struct tink_prf::subtle::HmacPrf

pub struct HmacPrf { /* fields omitted */ }

HmacPrf is a type that can be used to compute several HMACs with the same key material.

Implementations

impl HmacPrf

pub fn new(hash_alg: HashType, key: &[u8]) -> Result<HmacPrf, TinkError>

Create a new HmacPrf object and initialize it with the correct key material.

Trait Implementations

impl Clone for HmacPrf

fn clone(&self) -> HmacPrf

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Prf for HmacPrf

fn compute_prf(
    &self,
    data: &[u8],
    output_length: usize
) -> Result<Vec<u8>, TinkError>

Compute the PRF selected by the underlying key on input and returns the first output_length bytes. When choosing this parameter keep the birthday paradox in mind. If you have 2^n different inputs that your system has to handle set the output length (in bytes) to at least ceil(n/4 + 4) This corresponds to 2*n + 32 bits, meaning a collision will occur with a probability less than 1:2^32. When in doubt, request a security review. Returns a non ok status if the algorithm fails or if the output of algorithm is less than outputLength.