Struct KbkdfBuilder 

pub struct KbkdfBuilder<'a> { /* private fields */ }

KBKDF key-derivation builder (NIST SP 800-108).

Supports both HMAC-based and CMAC-based PRFs.

let key = KbkdfBuilder::new(KbkdfMode::Counter, &hmac_alg, &master_key)
    .digest(&sha256)
    .label(b"my label")
    .context(b"my context")
    .derive_to_vec(32)?;

Implementations

impl<'a> KbkdfBuilder<'a>

pub fn new(mode: KbkdfMode, mac: &'a MacAlg, key: &'a [u8]) -> Self

Create a KBKDF builder.

• mode — counter or feedback.
• mac — MAC algorithm (HMAC or CMAC).
• key — the key derivation key (KDK).

pub fn digest(self, digest: &'a DigestAlg) -> Self

Set the hash digest for HMAC-based derivation.

pub fn label(self, label: &'a [u8]) -> Self

Set the label (identifies the purpose of the derived key).

pub fn context(self, context: &'a [u8]) -> Self

Set the context (caller-specific data bound into the derivation).

pub fn salt(self, salt: &'a [u8]) -> Self

Set the salt / feedback IV (feedback mode only).

pub fn counter_len(self, len: KbkdfCounterLen) -> Self

Override the counter field length (default: 32 bits).

pub fn use_l(self, enabled: bool) -> Self

Control whether the length field L is included (default: true).

pub fn use_separator(self, enabled: bool) -> Self

Control whether the zero-byte separator is included (default: true).

pub fn derive(self, out: &mut [u8]) -> Result<(), ErrorStack>

Derive key material, writing into out.

Errors

pub fn derive_to_vec(self, len: usize) -> Result<Vec<u8>, ErrorStack>

Derive len bytes, returning them in a freshly allocated Vec<u8>.

Errors