weirwood 1.0.0

Privacy-preserving XGBoost inference via Fully Homomorphic Encryption
Documentation 
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//! Server-side FHE context: holds only the server key.
//!
//! [`ServerContext`] is the only thing the inference server needs.  It
//! contains the [`ServerKey`] required to perform homomorphic operations, but
//! **no private key material** — so sharing it with the server does not
//! compromise input privacy.
//!
//! In a real deployment the client serializes this context and sends it to the
//! server once; the server creates an [`FheEvaluator`] which installs the key
//! on its Rayon worker threads automatically.
//!
//! [`FheEvaluator`]: super::evaluator::FheEvaluator
//!
//! [`ServerKey`]: tfhe::ServerKey

use tfhe::ServerKey;

/// Server-side FHE context — contains only the [`ServerKey`], no private key.
///
/// Obtain a `ServerContext` from [`ClientContext::server_context`]; do not
/// construct one directly. Pass it to [`FheEvaluator::try_new`] (or the
/// unchecked [`FheEvaluator::new`]) to create an evaluator that can run
/// inference on encrypted inputs.
///
/// [`ClientContext::server_context`]: super::client::ClientContext::server_context
/// [`FheEvaluator::try_new`]: super::evaluator::FheEvaluator::try_new
/// [`FheEvaluator::new`]: super::evaluator::FheEvaluator::new
pub struct ServerContext {
    pub(crate) server_key: ServerKey,
}

impl ServerContext {
    pub(crate) fn from_key(server_key: ServerKey) -> Self {
        ServerContext { server_key }
    }
}