Struct UsmConfig 

pub struct UsmConfig {
    pub username: Bytes,
    pub auth: Option<(AuthProtocol, Vec<u8>)>,
    pub privacy: Option<(PrivProtocol, Vec<u8>)>,
    pub master_keys: Option<MasterKeys>,
}

USM user credentials for SNMPv3 authentication.

Stores the credentials needed for authenticated and/or encrypted communication. Keys are derived when the engine ID is discovered.

Master Key Caching

When polling many engines with shared credentials, use MasterKeys to cache the expensive password-to-key derivation. When master_keys is set, passwords are ignored and keys are derived from the cached master keys.

Fields

username: Bytes

Username for USM authentication

auth: Option<(AuthProtocol, Vec<u8>)>

Authentication protocol and password

privacy: Option<(PrivProtocol, Vec<u8>)>

Privacy protocol and password

master_keys: Option<MasterKeys>

Pre-computed master keys for efficient key derivation

Implementations

impl UsmConfig

pub fn new(username: impl Into<Bytes>) -> Self

Create a new USM config with just a username (noAuthNoPriv).

pub fn auth(self, protocol: AuthProtocol, password: impl AsRef<[u8]>) -> Self

Add authentication (authNoPriv or authPriv).

pub fn privacy(self, protocol: PrivProtocol, password: impl AsRef<[u8]>) -> Self

Add privacy/encryption (authPriv).

pub fn with_master_keys(self, master_keys: MasterKeys) -> Self

Use pre-computed master keys for efficient key derivation.

When set, passwords are ignored and keys are derived from the cached master keys. This avoids the expensive ~850us password expansion for each engine.

pub fn security_level(&self) -> SecurityLevel

Get the security level based on configured auth/privacy.

pub fn derive_keys(&self, engine_id: &[u8]) -> DerivedKeys

Derive localized keys for a specific engine ID.

If master keys are configured, uses the cached master keys for efficient localization (~1us). Otherwise, performs full password-to-key derivation (~850us for SHA-256).

Trait Implementations

impl Clone for UsmConfig

fn clone(&self) -> UsmConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for UsmConfig

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

Formats the value using the given formatter.