Struct MasterKeys 

pub struct MasterKeys { /* private fields */ }

Pre-computed master keys for SNMPv3 authentication and privacy.

This struct caches the expensive password-to-key derivation results for both authentication and privacy passwords. When polling many engines with shared credentials, create a MasterKeys once and use it with UsmBuilder to avoid repeating the ~850μs key derivation for each engine.

Example

use async_snmp::{AuthProtocol, PrivProtocol, MasterKeys};

// Create master keys once (expensive)
let master_keys = MasterKeys::new(AuthProtocol::Sha256, b"authpassword")
    .with_privacy(PrivProtocol::Aes128, b"privpassword");

// Use with multiple clients - localization is cheap (~1μs per engine)

Implementations

impl MasterKeys

pub fn new(auth_protocol: AuthProtocol, auth_password: &[u8]) -> Self

Create master keys with just authentication.

Example

use async_snmp::{AuthProtocol, MasterKeys};

let keys = MasterKeys::new(AuthProtocol::Sha256, b"authpassword");

pub fn with_privacy_same_password(self, priv_protocol: PrivProtocol) -> Self

Add privacy with the same password as authentication.

This is the common case where auth and priv passwords are identical. The same master key is reused, avoiding duplicate derivation.

pub fn with_privacy( self, priv_protocol: PrivProtocol, priv_password: &[u8], ) -> Self

Add privacy with a different password than authentication.

Use this when auth and priv passwords differ. A separate master key derivation is performed for the privacy password.

pub fn auth_master(&self) -> &MasterKey

Get the authentication master key.

pub fn priv_master(&self) -> Option<&MasterKey>

Get the privacy master key, if configured.

Returns the separate priv master key if set, otherwise returns the auth master key (for same-password case).

pub fn priv_protocol(&self) -> Option<PrivProtocol>

Get the configured privacy protocol.

pub fn auth_protocol(&self) -> AuthProtocol

Get the authentication protocol.

pub fn localize(&self, engine_id: &[u8]) -> (LocalizedKey, Option<PrivKey>)

Derive localized keys for a specific engine ID.

Returns (auth_key, priv_key) where priv_key is None if no privacy was configured.

Key extension is automatically applied when needed based on the auth/priv protocol combination:

• AES-192/256 with SHA-1 or MD5: Blumenthal extension (draft-blumenthal-aes-usm-04)
• 3DES with SHA-1 or MD5: Reeder extension (draft-reeder-snmpv3-usm-3desede-00)

Example

use async_snmp::{AuthProtocol, MasterKeys, PrivProtocol};

let keys = MasterKeys::new(AuthProtocol::Sha1, b"authpassword")
    .with_privacy_same_password(PrivProtocol::Aes256);

let engine_id = [0x80, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, 0x04];

// SHA-1 only produces 20 bytes, but AES-256 needs 32.
// Blumenthal extension is automatically applied.
let (auth, priv_key) = keys.localize(&engine_id);

Trait Implementations

impl Clone for MasterKeys

fn clone(&self) -> MasterKeys

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MasterKeys

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Drop for MasterKeys

fn drop(&mut self)

Executes the destructor for this type.

impl Zeroize for MasterKeys

fn zeroize(&mut self)

Zero out this object from memory using Rust intrinsics which ensure the zeroization operation is not “optimized away” by the compiler.