feat: porting of C2 [skip-line-limit]

Cargo.toml

@@ -106,6 +106,7 @@ e3-trbfv = { version = "0.1.8", path = "./crates/trbfv" }
 e3-utils = { version = "0.1.8", path = "./crates/utils" }
 e3-safe = { version = "0.1.8", path = "./crates/safe" }
 e3-zk-helpers = { version = "0.1.8", path = "./crates/zk-helpers" }
+e3-parity-matrix = { version = "0.1.8", path = "./crates/parity-matrix" }
 
 actix = "=0.13.5"
 actix-web = "=4.11.0"

circuits/lib/src/configs/insecure/dkg.nr

@@ -48,8 +48,8 @@ share_computation_sk (CIRCUIT 2a)
 ************************************/
 
 // share_computation_sk - bit parameters
-pub global SHARE_COMPUTATION_BIT_SHARE: u32 = 37;
-pub global SHARE_COMPUTATION_SK_BIT_SECRET: u32 = 2;
+pub global SHARE_COMPUTATION_BIT_SHARE: u32 = 36;
+pub global SHARE_COMPUTATION_SK_BIT_SECRET: u32 = 1;
 
 // share_computation_sk - configs
 pub global SHARE_COMPUTATION_SK_CONFIGS: ShareComputationConfigs<L_THRESHOLD> =
@@ -62,7 +62,7 @@ share_computation_e_sm (CIRCUIT 2b)
 ************************************/
 
 // share_computation_e_sm - bit parameters
-pub global SHARE_COMPUTATION_E_SM_BIT_SECRET: u32 = 18;
+pub global SHARE_COMPUTATION_E_SM_BIT_SECRET: u32 = 24;
 
 // verify_shares - configs
 pub global SHARE_COMPUTATION_E_SM_CONFIGS: ShareComputationConfigs<L_THRESHOLD> =

circuits/lib/src/configs/secure/dkg.nr

@@ -60,8 +60,8 @@ share_computation_sk (CIRCUIT 2a)
 ************************************/
 
 // share_computation_sk - bit parameters
-pub global SHARE_COMPUTATION_SK_BIT_SHARE: u32 = 54;
-pub global SHARE_COMPUTATION_SK_BIT_SECRET_SK: u32 = 2;
+pub global SHARE_COMPUTATION_BIT_SHARE: u32 = 53;
+pub global SHARE_COMPUTATION_SK_BIT_SECRET: u32 = 1;
 
 // share_computation_sk - configs
 pub global SHARE_COMPUTATION_SK_CONFIGS: ShareComputationConfigs<L_THRESHOLD> =
@@ -74,9 +74,9 @@ share_computation_e_sm (CIRCUIT 2b)
 ************************************/
 
 // share_computation_e_sm - bit parameters
-pub global SHARE_COMPUTATION_E_SM_BIT_E_SM: u32 = 187;
+pub global SHARE_COMPUTATION_E_SM_BIT_SECRET: u32 = 192;
 
-// share_computation_e_sm - configs
+// verify_shares - configs
 pub global SHARE_COMPUTATION_E_SM_CONFIGS: ShareComputationConfigs<L_THRESHOLD> =
     ShareComputationConfigs::new(QIS_THRESHOLD);
 

crates/fhe-params/src/lib.rs

@@ -15,11 +15,11 @@ pub mod search;
 
 pub use builder::{
     build_bfv_params, build_bfv_params_arc, build_bfv_params_from_set,
-    build_bfv_params_from_set_arc,
+    build_bfv_params_from_set_arc, build_pair_for_preset,
 };
 #[cfg(feature = "abi-encoding")]
 pub use encoding::{decode_bfv_params, decode_bfv_params_arc, encode_bfv_params, EncodingError};
 pub use presets::{
     default_param_set, BfvParamSet, BfvPreset, ParameterType, PresetError, PresetMetadata,
-    PresetSearchDefaults, DEFAULT_BFV_PRESET,
+    PresetSearchDefaults, SecurityTier, DEFAULT_BFV_PRESET,
 };

crates/fhe-params/src/presets.rs

@@ -81,6 +81,37 @@ pub enum ParameterType {
     DKG,
 }
 
+/// Security tier for BFV presets
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum SecurityTier {
+    /// Insecure security tier
+    INSECURE,
+    /// Secure security tier
+    SECURE,
+}
+
+impl SecurityTier {
+    /// Config path segment for Noir (e.g. `configs::{}::threshold`).
+    pub fn as_config_str(self) -> &'static str {
+        match self {
+            SecurityTier::INSECURE => "insecure",
+            SecurityTier::SECURE => "secure",
+        }
+    }
+}
+
+impl core::str::FromStr for SecurityTier {
+    type Err = PresetError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s.trim().to_lowercase().as_str() {
+            "insecure" => Ok(Self::INSECURE),
+            "secure" => Ok(Self::SECURE),
+            _ => Err(PresetError::UnknownPreset(s.to_string())),
+        }
+    }
+}
+
 /// Metadata describing a BFV preset configuration
 ///
 /// This struct contains high-level information about a preset, including
@@ -94,6 +125,10 @@ pub struct PresetMetadata {
     /// This determines the size of the polynomial ring R_q = Z_q[X]/(X^d + 1).
     /// Common values are 512, 1024, 2048, 4096, 8192, etc.
     pub degree: usize,
+    /// Number of moduli (l) - the number of moduli used in the ciphertext space
+    ///
+    /// This determines the size of the ciphertext space.
+    pub num_moduli: usize,
     /// Number of parties (n) - the number of ciphernodes in the system supported by
     /// the preset.
     ///
@@ -106,6 +141,8 @@ pub struct PresetMetadata {
     pub lambda: usize,
     /// Parameter type (DKG (BFV) / Threshold (trBFV)).
     pub parameter_type: ParameterType,
+    /// Security tier (e.g. for Noir `configs::{}::threshold`). Use [`SecurityTier::as_config_str`] for the path segment.
+    pub security: SecurityTier,
 }
 
 /// Default search parameters for BFV parameter generation
@@ -230,6 +267,24 @@ impl BfvPreset {
         }
     }
 
+    /// Parses "insecure"|"secure" or λ (e.g. 2|80) into the threshold preset. Uses [`PAIR_PRESETS`] and [`PresetMetadata`].
+    pub fn from_security_config_name(name: &str) -> Result<Self, PresetError> {
+        let s = name.trim();
+        if let Ok(lambda) = s.parse::<usize>() {
+            return Self::PAIR_PRESETS
+                .iter()
+                .copied()
+                .find(|p| p.metadata().lambda == lambda)
+                .ok_or_else(|| PresetError::UnknownPreset(format!("lambda {lambda}")));
+        }
+        let tier: SecurityTier = s.parse()?;
+        Self::PAIR_PRESETS
+            .iter()
+            .copied()
+            .find(|p| p.metadata().security == tier)
+            .ok_or_else(|| PresetError::UnknownPreset(name.to_string()))
+    }
+
     pub fn list() -> Vec<&'static str> {
         Self::ALL.iter().map(BfvPreset::name).collect()
     }
@@ -260,30 +315,38 @@ impl BfvPreset {
             BfvPreset::InsecureThreshold512 => PresetMetadata {
                 name: self.name(),
                 degree: insecure_512::DEGREE,
+                num_moduli: insecure_512::threshold::MODULI.len(),
                 num_parties: insecure_512::NUM_PARTIES,
                 lambda: DEFAULT_INSECURE_LAMBDA,
                 parameter_type: ParameterType::THRESHOLD,
+                security: SecurityTier::INSECURE,
             },
             BfvPreset::InsecureDkg512 => PresetMetadata {
                 name: self.name(),
                 degree: insecure_512::DEGREE,
+                num_moduli: insecure_512::dkg::MODULI.len(),
                 num_parties: insecure_512::NUM_PARTIES,
                 lambda: DEFAULT_INSECURE_LAMBDA,
                 parameter_type: ParameterType::DKG,
+                security: SecurityTier::INSECURE,
             },
             BfvPreset::SecureThreshold8192 => PresetMetadata {
                 name: self.name(),
                 degree: secure_8192::DEGREE,
+                num_moduli: secure_8192::threshold::MODULI.len(),
                 num_parties: secure_8192::NUM_PARTIES,
                 lambda: DEFAULT_SECURE_LAMBDA,
                 parameter_type: ParameterType::THRESHOLD,
+                security: SecurityTier::SECURE,
             },
             BfvPreset::SecureDkg8192 => PresetMetadata {
                 name: self.name(),
                 degree: secure_8192::DEGREE,
+                num_moduli: secure_8192::dkg::MODULI.len(),
                 num_parties: secure_8192::NUM_PARTIES,
                 lambda: DEFAULT_SECURE_LAMBDA,
                 parameter_type: ParameterType::DKG,
+                security: SecurityTier::SECURE,
             },
         }
     }

crates/parity-matrix/src/matrix.rs

@@ -12,7 +12,7 @@
 use crate::errors::{ConstraintError, MathError, ParityMatrixError, ParityMatrixResult};
 use crate::math::mod_inverse;
 use crate::math::mod_pow;
-use num_bigint::BigUint;
+use num_bigint::{BigInt, BigUint};
 use num_traits::{One, Zero};
 use serde::{Deserialize, Serialize};
 
@@ -105,6 +105,14 @@ impl ParityMatrix {
     pub fn get(&self, row: usize, col: usize) -> &BigUint {
         &self.data[row][col]
     }
+
+    /// Converts the matrix to rows of [`BigInt`] (non-negative; elements are in `[0, q)`).
+    pub fn to_bigint_rows(&self) -> Vec<Vec<BigInt>> {
+        self.data
+            .iter()
+            .map(|row| row.iter().map(|c| BigInt::from(c.clone())).collect())
+            .collect()
+    }
 }
 
 impl From<ParityMatrix> for Vec<Vec<BigUint>> {

crates/polynomial/src/crt_polynomial.rs

@@ -7,6 +7,7 @@
 //! CRT (Chinese Remainder Theorem) polynomial representation.
 
 use crate::polynomial::Polynomial;
+use crate::utils::reduce;
 use fhe_math::rq::{Poly, Representation};
 use num_bigint::BigInt;
 #[cfg(feature = "serde")]
@@ -52,6 +53,23 @@ impl CrtPolynomial {
         Self { limbs }
     }
 
+    /// Builds a CRT polynomial from a polynomial mod Q (Q>>128) and moduli.
+    ///
+    /// # Arguments
+    ///
+    /// * `coeffs` - Polynomial coefficients mod Q (Q>>128).
+    /// * `moduli` - One modulus per limb.
+    pub fn from_mod_q_polynomial(poly: &Vec<BigInt>, moduli: &[u64]) -> Self {
+        let limbs: Vec<Vec<BigInt>> = moduli
+            .iter()
+            .map(|&qi| {
+                let qi_big = BigInt::from(qi);
+                poly.iter().map(|c| reduce(c, &qi_big)).collect()
+            })
+            .collect();
+        Self::from_bigint_vectors(limbs)
+    }
+
     /// Builds a `CrtPolynomial` from an fhe-math `Poly` in PowerBasis representation.
     ///
     /// Used to prepare inputs for ZK circuits by converting FHE BFV ciphertext polynomials

crates/zk-helpers/Cargo.toml

@@ -25,6 +25,8 @@ serde = { workspace = true }
 serde_json = { workspace = true }
 toml = "0.8.23"
 itertools = "0.14.0"
+ndarray = { workspace = true }
+e3-parity-matrix = { workspace = true }
 
 [dev-dependencies]
 tempfile = { workspace = true }

crates/zk-helpers/README.md

@@ -1,26 +1,31 @@
 # zk-helpers
 
-ZK circuit artifact generation for the Noir prover.
+ZK circuit artifact generation for the Noir prover. Produces `configs.nr` and optionally
+`Prover.toml` for the Enclave circuits.
 
 ## zk-cli
 
-Generate `Prover.toml` and `configs.nr` for a circuit.
+Generate `configs.nr` for a circuit; use `--toml` to also generate `Prover.toml`.
 
 ```bash
 # List circuits
 cargo run -p e3-zk-helpers --bin zk_cli -- --list_circuits
 
-# Generate artifacts (default: output/)
-cargo run -p e3-zk-helpers --bin zk_cli -- --circuit pk-bfv --preset default
+# Generate configs.nr only (default)
+cargo run -p e3-zk-helpers --bin zk_cli -- --circuit pk --preset insecure
+cargo run -p e3-zk-helpers --bin zk_cli -- --circuit share-computation --preset insecure
 
-# Custom output dir; skip Prover.toml (only configs.nr)
-cargo run -p e3-zk-helpers --bin zk_cli -- --circuit pk-bfv --preset default --output ./artifacts --toml
+# Generate configs.nr and Prover.toml (--witness required for share-computation)
+cargo run -p e3-zk-helpers --bin zk_cli -- --circuit pk --preset insecure --toml
+cargo run -p e3-zk-helpers --bin zk_cli -- --circuit share-computation --preset insecure --witness secret-key --toml
+cargo run -p e3-zk-helpers --bin zk_cli -- --circuit share-computation --preset secure --witness smudging-noise --toml
 ```
 
-| Flag               | Description                                        |
-| ------------------ | -------------------------------------------------- |
-| `--list_circuits`  | List circuits and exit                             |
-| `--circuit <name>` | Circuit (e.g. `pk-bfv`)                            |
-| `--preset <name>`  | BFV preset (must match circuit)                    |
-| `--output <path>`  | Output dir (default: `output`)                     |
-| `--toml`           | Skip writing Prover.toml; always writes configs.nr |
+| Flag               | Description                                                                   |
+| ------------------ | ----------------------------------------------------------------------------- |
+| `--list_circuits`  | List circuits and exit                                                        |
+| `--circuit <name>` | Circuit: `pk` or `share-computation`                                          |
+| `--preset <name>`  | Security preset: `insecure` (512) or `secure` (8192)                          |
+| `--witness <type>` | For `share-computation` when using `--toml`: `secret-key` or `smudging-noise` |
+| `--output <path>`  | Output dir (default: `output`)                                                |
+| `--toml`           | Also write Prover.toml (default: configs.nr only)                             |