mirror of https://github.com/zcash/halo2.git
1134 lines
40 KiB
Rust
1134 lines
40 KiB
Rust
//! Tools for developing circuits.
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use std::collections::HashMap;
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use std::collections::HashSet;
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use std::iter;
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use std::ops::{Add, Mul, Neg, Range};
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use ff::Field;
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use crate::plonk::Assigned;
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use crate::{
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circuit,
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plonk::{
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permutation, Advice, Any, Assignment, Circuit, Column, ConstraintSystem, Error, Expression,
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Fixed, FloorPlanner, Instance, Selector,
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},
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};
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pub mod metadata;
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mod util;
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mod failure;
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pub use failure::{FailureLocation, VerifyFailure};
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pub mod cost;
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pub use cost::CircuitCost;
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mod gates;
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pub use gates::CircuitGates;
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#[cfg(feature = "dev-graph")]
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mod graph;
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#[cfg(feature = "dev-graph")]
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#[cfg_attr(docsrs, doc(cfg(feature = "dev-graph")))]
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pub use graph::{circuit_dot_graph, layout::CircuitLayout};
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#[derive(Debug)]
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struct Region {
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/// The name of the region. Not required to be unique.
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name: String,
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/// The columns involved in this region.
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columns: HashSet<Column<Any>>,
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/// The rows that this region starts and ends on, if known.
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rows: Option<(usize, usize)>,
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/// The selectors that have been enabled in this region. All other selectors are by
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/// construction not enabled.
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enabled_selectors: HashMap<Selector, Vec<usize>>,
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/// The cells assigned in this region. We store this as a `Vec` so that if any cells
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/// are double-assigned, they will be visibly darker.
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cells: Vec<(Column<Any>, usize)>,
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}
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impl Region {
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fn update_extent(&mut self, column: Column<Any>, row: usize) {
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self.columns.insert(column);
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// The region start is the earliest row assigned to.
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// The region end is the latest row assigned to.
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let (mut start, mut end) = self.rows.unwrap_or((row, row));
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if row < start {
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// The first row assigned was not at start 0 within the region.
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start = row;
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}
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if row > end {
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end = row;
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}
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self.rows = Some((start, end));
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}
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}
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/// The value of a particular cell within the circuit.
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#[derive(Clone, Copy, Debug, PartialEq, Eq)]
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enum CellValue<F: Field> {
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// An unassigned cell.
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Unassigned,
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// A cell that has been assigned a value.
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Assigned(F),
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// A unique poisoned cell.
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Poison(usize),
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}
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/// A value within an expression.
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#[derive(Clone, Copy, Debug, PartialEq, Eq, Ord, PartialOrd)]
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enum Value<F: Field> {
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Real(F),
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Poison,
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}
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impl<F: Field> From<CellValue<F>> for Value<F> {
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fn from(value: CellValue<F>) -> Self {
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match value {
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// Cells that haven't been explicitly assigned to, default to zero.
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CellValue::Unassigned => Value::Real(F::ZERO),
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CellValue::Assigned(v) => Value::Real(v),
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CellValue::Poison(_) => Value::Poison,
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}
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}
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}
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impl<F: Field> Neg for Value<F> {
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type Output = Self;
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fn neg(self) -> Self::Output {
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match self {
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Value::Real(a) => Value::Real(-a),
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_ => Value::Poison,
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}
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}
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}
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impl<F: Field> Add for Value<F> {
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type Output = Self;
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fn add(self, rhs: Self) -> Self::Output {
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match (self, rhs) {
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(Value::Real(a), Value::Real(b)) => Value::Real(a + b),
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_ => Value::Poison,
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}
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}
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}
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impl<F: Field> Mul for Value<F> {
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type Output = Self;
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fn mul(self, rhs: Self) -> Self::Output {
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match (self, rhs) {
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(Value::Real(a), Value::Real(b)) => Value::Real(a * b),
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// If poison is multiplied by zero, then we treat the poison as unconstrained
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// and we don't propagate it.
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(Value::Real(x), Value::Poison) | (Value::Poison, Value::Real(x))
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if x.is_zero_vartime() =>
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{
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Value::Real(F::ZERO)
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}
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_ => Value::Poison,
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}
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}
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}
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impl<F: Field> Mul<F> for Value<F> {
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type Output = Self;
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fn mul(self, rhs: F) -> Self::Output {
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match self {
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Value::Real(lhs) => Value::Real(lhs * rhs),
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// If poison is multiplied by zero, then we treat the poison as unconstrained
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// and we don't propagate it.
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Value::Poison if rhs.is_zero_vartime() => Value::Real(F::ZERO),
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_ => Value::Poison,
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}
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}
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}
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/// A test prover for debugging circuits.
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///
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/// The normal proving process, when applied to a buggy circuit implementation, might
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/// return proofs that do not validate when they should, but it can't indicate anything
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/// other than "something is invalid". `MockProver` can be used to figure out _why_ these
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/// are invalid: it stores all the private inputs along with the circuit internals, and
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/// then checks every constraint manually.
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///
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/// # Examples
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///
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/// ```
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/// use group::ff::PrimeField;
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/// use halo2_proofs::{
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/// circuit::{Layouter, SimpleFloorPlanner, Value},
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/// dev::{FailureLocation, MockProver, VerifyFailure},
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/// pasta::Fp,
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/// plonk::{Advice, Any, Circuit, Column, ConstraintSystem, Error, Selector},
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/// poly::Rotation,
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/// };
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/// const K: u32 = 5;
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///
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/// #[derive(Copy, Clone)]
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/// struct MyConfig {
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/// a: Column<Advice>,
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/// b: Column<Advice>,
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/// c: Column<Advice>,
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/// s: Selector,
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/// }
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///
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/// #[derive(Clone, Default)]
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/// struct MyCircuit {
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/// a: Value<u64>,
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/// b: Value<u64>,
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/// }
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///
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/// impl<F: PrimeField> Circuit<F> for MyCircuit {
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/// type Config = MyConfig;
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/// type FloorPlanner = SimpleFloorPlanner;
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///
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/// fn without_witnesses(&self) -> Self {
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/// Self::default()
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/// }
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///
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/// fn configure(meta: &mut ConstraintSystem<F>) -> MyConfig {
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/// let a = meta.advice_column();
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/// let b = meta.advice_column();
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/// let c = meta.advice_column();
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/// let s = meta.selector();
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///
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/// meta.create_gate("R1CS constraint", |meta| {
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/// let a = meta.query_advice(a, Rotation::cur());
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/// let b = meta.query_advice(b, Rotation::cur());
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/// let c = meta.query_advice(c, Rotation::cur());
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/// let s = meta.query_selector(s);
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///
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/// // BUG: Should be a * b - c
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/// Some(("buggy R1CS", s * (a * b + c)))
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/// });
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///
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/// MyConfig { a, b, c, s }
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/// }
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///
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/// fn synthesize(&self, config: MyConfig, mut layouter: impl Layouter<F>) -> Result<(), Error> {
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/// layouter.assign_region(|| "Example region", |mut region| {
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/// config.s.enable(&mut region, 0)?;
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/// region.assign_advice(|| "a", config.a, 0, || {
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/// self.a.map(F::from)
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/// })?;
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/// region.assign_advice(|| "b", config.b, 0, || {
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/// self.b.map(F::from)
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/// })?;
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/// region.assign_advice(|| "c", config.c, 0, || {
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/// (self.a * self.b).map(F::from)
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/// })?;
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/// Ok(())
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/// })
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/// }
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/// }
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///
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/// // Assemble the private inputs to the circuit.
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/// let circuit = MyCircuit {
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/// a: Value::known(2),
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/// b: Value::known(4),
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/// };
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///
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/// // This circuit has no public inputs.
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/// let instance = vec![];
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///
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/// let prover = MockProver::<Fp>::run(K, &circuit, instance).unwrap();
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/// assert_eq!(
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/// prover.verify(),
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/// Err(vec![VerifyFailure::ConstraintNotSatisfied {
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/// constraint: ((0, "R1CS constraint").into(), 0, "buggy R1CS").into(),
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/// location: FailureLocation::InRegion {
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/// region: (0, "Example region").into(),
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/// offset: 0,
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/// },
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/// cell_values: vec![
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/// (((Any::Advice, 0).into(), 0).into(), "0x2".to_string()),
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/// (((Any::Advice, 1).into(), 0).into(), "0x4".to_string()),
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/// (((Any::Advice, 2).into(), 0).into(), "0x8".to_string()),
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/// ],
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/// }])
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/// );
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///
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/// // If we provide a too-small K, we get an error.
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/// assert!(matches!(
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/// MockProver::<Fp>::run(2, &circuit, vec![]).unwrap_err(),
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/// Error::NotEnoughRowsAvailable {
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/// current_k,
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/// } if current_k == 2,
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/// ));
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/// ```
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#[derive(Debug)]
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pub struct MockProver<F: Field> {
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k: u32,
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n: u32,
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cs: ConstraintSystem<F>,
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/// The regions in the circuit.
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regions: Vec<Region>,
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/// The current region being assigned to. Will be `None` after the circuit has been
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/// synthesized.
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current_region: Option<Region>,
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// The fixed cells in the circuit, arranged as [column][row].
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fixed: Vec<Vec<CellValue<F>>>,
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// The advice cells in the circuit, arranged as [column][row].
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advice: Vec<Vec<CellValue<F>>>,
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// The instance cells in the circuit, arranged as [column][row].
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instance: Vec<Vec<InstanceValue<F>>>,
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selectors: Vec<Vec<bool>>,
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permutation: permutation::keygen::Assembly,
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// A range of available rows for assignment and copies.
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usable_rows: Range<usize>,
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}
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#[derive(Debug, Clone, PartialEq, Eq)]
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enum InstanceValue<F: Field> {
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Assigned(F),
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Padding,
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}
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impl<F: Field> InstanceValue<F> {
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fn value(&self) -> F {
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match self {
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InstanceValue::Assigned(v) => *v,
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InstanceValue::Padding => F::ZERO,
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}
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}
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}
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impl<F: Field> Assignment<F> for MockProver<F> {
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fn enter_region<NR, N>(&mut self, name: N)
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where
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NR: Into<String>,
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N: FnOnce() -> NR,
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{
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assert!(self.current_region.is_none());
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self.current_region = Some(Region {
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name: name().into(),
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columns: HashSet::default(),
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rows: None,
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enabled_selectors: HashMap::default(),
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cells: vec![],
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});
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}
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fn exit_region(&mut self) {
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self.regions.push(self.current_region.take().unwrap());
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}
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fn enable_selector<A, AR>(&mut self, _: A, selector: &Selector, row: usize) -> Result<(), Error>
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where
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A: FnOnce() -> AR,
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AR: Into<String>,
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{
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if !self.usable_rows.contains(&row) {
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return Err(Error::not_enough_rows_available(self.k));
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}
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// Track that this selector was enabled. We require that all selectors are enabled
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// inside some region (i.e. no floating selectors).
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self.current_region
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.as_mut()
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.unwrap()
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.enabled_selectors
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.entry(*selector)
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.or_default()
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.push(row);
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self.selectors[selector.0][row] = true;
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Ok(())
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}
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fn query_instance(
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&self,
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column: Column<Instance>,
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row: usize,
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) -> Result<circuit::Value<F>, Error> {
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if !self.usable_rows.contains(&row) {
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return Err(Error::not_enough_rows_available(self.k));
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}
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self.instance
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.get(column.index())
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.and_then(|column| column.get(row))
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.map(|v| circuit::Value::known(v.value()))
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.ok_or(Error::BoundsFailure)
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}
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fn assign_advice<V, VR, A, AR>(
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&mut self,
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_: A,
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column: Column<Advice>,
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row: usize,
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to: V,
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) -> Result<(), Error>
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where
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V: FnOnce() -> circuit::Value<VR>,
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VR: Into<Assigned<F>>,
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A: FnOnce() -> AR,
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AR: Into<String>,
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{
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if !self.usable_rows.contains(&row) {
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return Err(Error::not_enough_rows_available(self.k));
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}
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if let Some(region) = self.current_region.as_mut() {
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region.update_extent(column.into(), row);
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region.cells.push((column.into(), row));
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}
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*self
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.advice
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.get_mut(column.index())
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.and_then(|v| v.get_mut(row))
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.ok_or(Error::BoundsFailure)? =
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CellValue::Assigned(to().into_field().evaluate().assign()?);
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Ok(())
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}
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fn assign_fixed<V, VR, A, AR>(
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&mut self,
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_: A,
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column: Column<Fixed>,
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row: usize,
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to: V,
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) -> Result<(), Error>
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where
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V: FnOnce() -> circuit::Value<VR>,
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VR: Into<Assigned<F>>,
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A: FnOnce() -> AR,
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AR: Into<String>,
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{
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if !self.usable_rows.contains(&row) {
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return Err(Error::not_enough_rows_available(self.k));
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}
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if let Some(region) = self.current_region.as_mut() {
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region.update_extent(column.into(), row);
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region.cells.push((column.into(), row));
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}
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*self
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.fixed
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.get_mut(column.index())
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.and_then(|v| v.get_mut(row))
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.ok_or(Error::BoundsFailure)? =
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CellValue::Assigned(to().into_field().evaluate().assign()?);
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Ok(())
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}
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fn copy(
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&mut self,
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left_column: Column<Any>,
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left_row: usize,
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right_column: Column<Any>,
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right_row: usize,
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) -> Result<(), crate::plonk::Error> {
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if !self.usable_rows.contains(&left_row) || !self.usable_rows.contains(&right_row) {
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return Err(Error::not_enough_rows_available(self.k));
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}
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self.permutation
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.copy(left_column, left_row, right_column, right_row)
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}
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fn fill_from_row(
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&mut self,
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col: Column<Fixed>,
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from_row: usize,
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to: circuit::Value<Assigned<F>>,
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) -> Result<(), Error> {
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if !self.usable_rows.contains(&from_row) {
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return Err(Error::not_enough_rows_available(self.k));
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}
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for row in self.usable_rows.clone().skip(from_row) {
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self.assign_fixed(|| "", col, row, || to)?;
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}
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Ok(())
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}
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|
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fn push_namespace<NR, N>(&mut self, _: N)
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where
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NR: Into<String>,
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N: FnOnce() -> NR,
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{
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// TODO: Do something with namespaces :)
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}
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fn pop_namespace(&mut self, _: Option<String>) {
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// TODO: Do something with namespaces :)
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}
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}
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|
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impl<F: Field + Ord> MockProver<F> {
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/// Runs a synthetic keygen-and-prove operation on the given circuit, collecting data
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/// about the constraints and their assignments.
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pub fn run<ConcreteCircuit: Circuit<F>>(
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k: u32,
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circuit: &ConcreteCircuit,
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instance: Vec<Vec<F>>,
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) -> Result<Self, Error> {
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let n = 1 << k;
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let mut cs = ConstraintSystem::default();
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let config = ConcreteCircuit::configure(&mut cs);
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let cs = cs;
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if n < cs.minimum_rows() {
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return Err(Error::not_enough_rows_available(k));
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}
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if instance.len() != cs.num_instance_columns {
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return Err(Error::InvalidInstances);
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}
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let instance = instance
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.into_iter()
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.map(|instance| {
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if instance.len() > n - (cs.blinding_factors() + 1) {
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return Err(Error::InstanceTooLarge);
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}
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let mut instance_values = vec![InstanceValue::Padding; n];
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for (idx, value) in instance.into_iter().enumerate() {
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instance_values[idx] = InstanceValue::Assigned(value);
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}
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Ok(instance_values)
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})
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.collect::<Result<Vec<_>, _>>()?;
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|
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// Fixed columns contain no blinding factors.
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let fixed = vec![vec![CellValue::Unassigned; n]; cs.num_fixed_columns];
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let selectors = vec![vec![false; n]; cs.num_selectors];
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// Advice columns contain blinding factors.
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let blinding_factors = cs.blinding_factors();
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let usable_rows = n - (blinding_factors + 1);
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let advice = vec![
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{
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let mut column = vec![CellValue::Unassigned; n];
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// Poison unusable rows.
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for (i, cell) in column.iter_mut().enumerate().skip(usable_rows) {
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*cell = CellValue::Poison(i);
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}
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column
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};
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cs.num_advice_columns
|
|
];
|
|
let permutation = permutation::keygen::Assembly::new(n, &cs.permutation);
|
|
let constants = cs.constants.clone();
|
|
|
|
let mut prover = MockProver {
|
|
k,
|
|
n: n as u32,
|
|
cs,
|
|
regions: vec![],
|
|
current_region: None,
|
|
fixed,
|
|
advice,
|
|
instance,
|
|
selectors,
|
|
permutation,
|
|
usable_rows: 0..usable_rows,
|
|
};
|
|
|
|
ConcreteCircuit::FloorPlanner::synthesize(&mut prover, circuit, config, constants)?;
|
|
|
|
let (cs, selector_polys) = prover.cs.compress_selectors(prover.selectors.clone());
|
|
prover.cs = cs;
|
|
prover.fixed.extend(selector_polys.into_iter().map(|poly| {
|
|
let mut v = vec![CellValue::Unassigned; n];
|
|
for (v, p) in v.iter_mut().zip(&poly[..]) {
|
|
*v = CellValue::Assigned(*p);
|
|
}
|
|
v
|
|
}));
|
|
|
|
Ok(prover)
|
|
}
|
|
|
|
/// Returns `Ok(())` if this `MockProver` is satisfied, or a list of errors indicating
|
|
/// the reasons that the circuit is not satisfied.
|
|
pub fn verify(&self) -> Result<(), Vec<VerifyFailure>> {
|
|
let n = self.n as i32;
|
|
|
|
// Check that within each region, all cells used in instantiated gates have been
|
|
// assigned to.
|
|
let selector_errors = self.regions.iter().enumerate().flat_map(|(r_i, r)| {
|
|
r.enabled_selectors.iter().flat_map(move |(selector, at)| {
|
|
// Find the gates enabled by this selector
|
|
self.cs
|
|
.gates
|
|
.iter()
|
|
// Assume that if a queried selector is enabled, the user wants to use the
|
|
// corresponding gate in some way.
|
|
//
|
|
// TODO: This will trip up on the reverse case, where leaving a selector
|
|
// un-enabled keeps a gate enabled. We could alternatively require that
|
|
// every selector is explicitly enabled or disabled on every row? But that
|
|
// seems messy and confusing.
|
|
.enumerate()
|
|
.filter(move |(_, g)| g.queried_selectors().contains(selector))
|
|
.flat_map(move |(gate_index, gate)| {
|
|
at.iter().flat_map(move |selector_row| {
|
|
// Selectors are queried with no rotation.
|
|
let gate_row = *selector_row as i32;
|
|
|
|
gate.queried_cells().iter().filter_map(move |cell| {
|
|
// Determine where this cell should have been assigned.
|
|
let cell_row = ((gate_row + n + cell.rotation.0) % n) as usize;
|
|
|
|
match cell.column.column_type() {
|
|
Any::Instance => {
|
|
// Handle instance cells, which are not in the region.
|
|
let instance_value =
|
|
&self.instance[cell.column.index()][cell_row];
|
|
match instance_value {
|
|
InstanceValue::Assigned(_) => None,
|
|
_ => Some(VerifyFailure::InstanceCellNotAssigned {
|
|
gate: (gate_index, gate.name()).into(),
|
|
region: (r_i, r.name.clone()).into(),
|
|
gate_offset: *selector_row,
|
|
column: cell.column.try_into().unwrap(),
|
|
row: cell_row,
|
|
}),
|
|
}
|
|
}
|
|
_ => {
|
|
// Check that it was assigned!
|
|
if r.cells.contains(&(cell.column, cell_row)) {
|
|
None
|
|
} else {
|
|
Some(VerifyFailure::CellNotAssigned {
|
|
gate: (gate_index, gate.name()).into(),
|
|
region: (r_i, r.name.clone()).into(),
|
|
gate_offset: *selector_row,
|
|
column: cell.column,
|
|
offset: cell_row as isize
|
|
- r.rows.unwrap().0 as isize,
|
|
})
|
|
}
|
|
}
|
|
}
|
|
})
|
|
})
|
|
})
|
|
})
|
|
});
|
|
|
|
// Check that all gates are satisfied for all rows.
|
|
let gate_errors =
|
|
self.cs
|
|
.gates
|
|
.iter()
|
|
.enumerate()
|
|
.flat_map(|(gate_index, gate)| {
|
|
// We iterate from n..2n so we can just reduce to handle wrapping.
|
|
(n..(2 * n)).flat_map(move |row| {
|
|
gate.polynomials().iter().enumerate().filter_map(
|
|
move |(poly_index, poly)| match poly.evaluate(
|
|
&|scalar| Value::Real(scalar),
|
|
&|_| panic!("virtual selectors are removed during optimization"),
|
|
&util::load(n, row, &self.cs.fixed_queries, &self.fixed),
|
|
&util::load(n, row, &self.cs.advice_queries, &self.advice),
|
|
&util::load_instance(
|
|
n,
|
|
row,
|
|
&self.cs.instance_queries,
|
|
&self.instance,
|
|
),
|
|
&|a| -a,
|
|
&|a, b| a + b,
|
|
&|a, b| a * b,
|
|
&|a, scalar| a * scalar,
|
|
) {
|
|
Value::Real(x) if x.is_zero_vartime() => None,
|
|
Value::Real(_) => Some(VerifyFailure::ConstraintNotSatisfied {
|
|
constraint: (
|
|
(gate_index, gate.name()).into(),
|
|
poly_index,
|
|
gate.constraint_name(poly_index),
|
|
)
|
|
.into(),
|
|
location: FailureLocation::find_expressions(
|
|
&self.cs,
|
|
&self.regions,
|
|
(row - n) as usize,
|
|
Some(poly).into_iter(),
|
|
),
|
|
cell_values: util::cell_values(
|
|
gate,
|
|
poly,
|
|
&util::load(n, row, &self.cs.fixed_queries, &self.fixed),
|
|
&util::load(n, row, &self.cs.advice_queries, &self.advice),
|
|
&util::load_instance(
|
|
n,
|
|
row,
|
|
&self.cs.instance_queries,
|
|
&self.instance,
|
|
),
|
|
),
|
|
}),
|
|
Value::Poison => Some(VerifyFailure::ConstraintPoisoned {
|
|
constraint: (
|
|
(gate_index, gate.name()).into(),
|
|
poly_index,
|
|
gate.constraint_name(poly_index),
|
|
)
|
|
.into(),
|
|
}),
|
|
},
|
|
)
|
|
})
|
|
});
|
|
|
|
// Check that all lookups exist in their respective tables.
|
|
let lookup_errors =
|
|
self.cs
|
|
.lookups
|
|
.iter()
|
|
.enumerate()
|
|
.flat_map(|(lookup_index, lookup)| {
|
|
let load = |expression: &Expression<F>, row| {
|
|
expression.evaluate(
|
|
&|scalar| Value::Real(scalar),
|
|
&|_| panic!("virtual selectors are removed during optimization"),
|
|
&|query| {
|
|
let query = self.cs.fixed_queries[query.index];
|
|
let column_index = query.0.index();
|
|
let rotation = query.1 .0;
|
|
self.fixed[column_index]
|
|
[(row as i32 + n + rotation) as usize % n as usize]
|
|
.into()
|
|
},
|
|
&|query| {
|
|
let query = self.cs.advice_queries[query.index];
|
|
let column_index = query.0.index();
|
|
let rotation = query.1 .0;
|
|
self.advice[column_index]
|
|
[(row as i32 + n + rotation) as usize % n as usize]
|
|
.into()
|
|
},
|
|
&|query| {
|
|
let query = self.cs.instance_queries[query.index];
|
|
let column_index = query.0.index();
|
|
let rotation = query.1 .0;
|
|
Value::Real(
|
|
self.instance[column_index]
|
|
[(row as i32 + n + rotation) as usize % n as usize]
|
|
.value(),
|
|
)
|
|
},
|
|
&|a| -a,
|
|
&|a, b| a + b,
|
|
&|a, b| a * b,
|
|
&|a, scalar| a * scalar,
|
|
)
|
|
};
|
|
|
|
assert!(lookup.table_expressions.len() == lookup.input_expressions.len());
|
|
assert!(self.usable_rows.end > 0);
|
|
|
|
// We optimize on the basis that the table might have been filled so that the last
|
|
// usable row now has the fill contents (it doesn't matter if there was no filling).
|
|
// Note that this "fill row" necessarily exists in the table, and we use that fact to
|
|
// slightly simplify the optimization: we're only trying to check that all input rows
|
|
// are contained in the table, and so we can safely just drop input rows that
|
|
// match the fill row.
|
|
let fill_row: Vec<_> = lookup
|
|
.table_expressions
|
|
.iter()
|
|
.map(move |c| load(c, self.usable_rows.end - 1))
|
|
.collect();
|
|
|
|
// In the real prover, the lookup expressions are never enforced on
|
|
// unusable rows, due to the (1 - (l_last(X) + l_blind(X))) term.
|
|
let mut table: Vec<Vec<_>> = self
|
|
.usable_rows
|
|
.clone()
|
|
.filter_map(|table_row| {
|
|
let t = lookup
|
|
.table_expressions
|
|
.iter()
|
|
.map(move |c| load(c, table_row))
|
|
.collect();
|
|
|
|
if t != fill_row {
|
|
Some(t)
|
|
} else {
|
|
None
|
|
}
|
|
})
|
|
.collect();
|
|
table.sort_unstable();
|
|
|
|
let mut inputs: Vec<(Vec<_>, usize)> = self
|
|
.usable_rows
|
|
.clone()
|
|
.filter_map(|input_row| {
|
|
let t = lookup
|
|
.input_expressions
|
|
.iter()
|
|
.map(move |c| load(c, input_row))
|
|
.collect();
|
|
|
|
if t != fill_row {
|
|
// Also keep track of the original input row, since we're going to sort.
|
|
Some((t, input_row))
|
|
} else {
|
|
None
|
|
}
|
|
})
|
|
.collect();
|
|
inputs.sort_unstable();
|
|
|
|
let mut i = 0;
|
|
inputs
|
|
.iter()
|
|
.filter_map(move |(input, input_row)| {
|
|
while i < table.len() && &table[i] < input {
|
|
i += 1;
|
|
}
|
|
if i == table.len() || &table[i] > input {
|
|
assert!(table.binary_search(input).is_err());
|
|
|
|
Some(VerifyFailure::Lookup {
|
|
lookup_index,
|
|
location: FailureLocation::find_expressions(
|
|
&self.cs,
|
|
&self.regions,
|
|
*input_row,
|
|
lookup.input_expressions.iter(),
|
|
),
|
|
})
|
|
} else {
|
|
None
|
|
}
|
|
})
|
|
.collect::<Vec<_>>()
|
|
});
|
|
|
|
// Check that permutations preserve the original values of the cells.
|
|
let perm_errors = {
|
|
// Original values of columns involved in the permutation.
|
|
let original = |column, row| {
|
|
self.cs
|
|
.permutation
|
|
.get_columns()
|
|
.get(column)
|
|
.map(|c: &Column<Any>| match c.column_type() {
|
|
Any::Advice => self.advice[c.index()][row],
|
|
Any::Fixed => self.fixed[c.index()][row],
|
|
Any::Instance => {
|
|
let cell: &InstanceValue<F> = &self.instance[c.index()][row];
|
|
CellValue::Assigned(cell.value())
|
|
}
|
|
})
|
|
.unwrap()
|
|
};
|
|
|
|
// Iterate over each column of the permutation
|
|
self.permutation
|
|
.mapping
|
|
.iter()
|
|
.enumerate()
|
|
.flat_map(move |(column, values)| {
|
|
// Iterate over each row of the column to check that the cell's
|
|
// value is preserved by the mapping.
|
|
values.iter().enumerate().filter_map(move |(row, cell)| {
|
|
let original_cell = original(column, row);
|
|
let permuted_cell = original(cell.0, cell.1);
|
|
if original_cell == permuted_cell {
|
|
None
|
|
} else {
|
|
let columns = self.cs.permutation.get_columns();
|
|
let column = columns.get(column).unwrap();
|
|
Some(VerifyFailure::Permutation {
|
|
column: (*column).into(),
|
|
location: FailureLocation::find(
|
|
&self.regions,
|
|
row,
|
|
Some(column).into_iter().cloned().collect(),
|
|
),
|
|
})
|
|
}
|
|
})
|
|
})
|
|
};
|
|
|
|
let mut errors: Vec<_> = iter::empty()
|
|
.chain(selector_errors)
|
|
.chain(gate_errors)
|
|
.chain(lookup_errors)
|
|
.chain(perm_errors)
|
|
.collect();
|
|
if errors.is_empty() {
|
|
Ok(())
|
|
} else {
|
|
// Remove any duplicate `ConstraintPoisoned` errors (we check all unavailable
|
|
// rows in case the trigger is row-specific, but the error message only points
|
|
// at the constraint).
|
|
errors.dedup_by(|a, b| match (a, b) {
|
|
(
|
|
a @ VerifyFailure::ConstraintPoisoned { .. },
|
|
b @ VerifyFailure::ConstraintPoisoned { .. },
|
|
) => a == b,
|
|
_ => false,
|
|
});
|
|
Err(errors)
|
|
}
|
|
}
|
|
|
|
/// Panics if the circuit being checked by this `MockProver` is not satisfied.
|
|
///
|
|
/// Any verification failures will be pretty-printed to stderr before the function
|
|
/// panics.
|
|
///
|
|
/// Apart from the stderr output, this method is equivalent to:
|
|
/// ```ignore
|
|
/// assert_eq!(prover.verify(), Ok(()));
|
|
/// ```
|
|
pub fn assert_satisfied(&self) {
|
|
if let Err(errs) = self.verify() {
|
|
for err in errs {
|
|
err.emit(self);
|
|
eprintln!();
|
|
}
|
|
panic!("circuit was not satisfied");
|
|
}
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use group::ff::Field;
|
|
use pasta_curves::Fp;
|
|
|
|
use super::{FailureLocation, MockProver, VerifyFailure};
|
|
use crate::{
|
|
circuit::{Layouter, SimpleFloorPlanner, Value},
|
|
plonk::{
|
|
Advice, Any, Circuit, Column, ConstraintSystem, Error, Expression, Selector,
|
|
TableColumn,
|
|
},
|
|
poly::Rotation,
|
|
};
|
|
|
|
#[test]
|
|
fn unassigned_cell() {
|
|
const K: u32 = 4;
|
|
|
|
#[derive(Clone)]
|
|
struct FaultyCircuitConfig {
|
|
a: Column<Advice>,
|
|
q: Selector,
|
|
}
|
|
|
|
struct FaultyCircuit {}
|
|
|
|
impl Circuit<Fp> for FaultyCircuit {
|
|
type Config = FaultyCircuitConfig;
|
|
type FloorPlanner = SimpleFloorPlanner;
|
|
|
|
fn configure(meta: &mut ConstraintSystem<Fp>) -> Self::Config {
|
|
let a = meta.advice_column();
|
|
let b = meta.advice_column();
|
|
let q = meta.selector();
|
|
|
|
meta.create_gate("Equality check", |cells| {
|
|
let a = cells.query_advice(a, Rotation::prev());
|
|
let b = cells.query_advice(b, Rotation::cur());
|
|
let q = cells.query_selector(q);
|
|
|
|
// If q is enabled, a and b must be assigned to.
|
|
vec![q * (a - b)]
|
|
});
|
|
|
|
FaultyCircuitConfig { a, q }
|
|
}
|
|
|
|
fn without_witnesses(&self) -> Self {
|
|
Self {}
|
|
}
|
|
|
|
fn synthesize(
|
|
&self,
|
|
config: Self::Config,
|
|
mut layouter: impl Layouter<Fp>,
|
|
) -> Result<(), Error> {
|
|
layouter.assign_region(
|
|
|| "Faulty synthesis",
|
|
|mut region| {
|
|
// Enable the equality gate.
|
|
config.q.enable(&mut region, 1)?;
|
|
|
|
// Assign a = 0.
|
|
region.assign_advice(|| "a", config.a, 0, || Value::known(Fp::ZERO))?;
|
|
|
|
// BUG: Forget to assign b = 0! This could go unnoticed during
|
|
// development, because cell values default to zero, which in this
|
|
// case is fine, but for other assignments would be broken.
|
|
Ok(())
|
|
},
|
|
)
|
|
}
|
|
}
|
|
|
|
let prover = MockProver::run(K, &FaultyCircuit {}, vec![]).unwrap();
|
|
assert_eq!(
|
|
prover.verify(),
|
|
Err(vec![VerifyFailure::CellNotAssigned {
|
|
gate: (0, "Equality check").into(),
|
|
region: (0, "Faulty synthesis".to_owned()).into(),
|
|
gate_offset: 1,
|
|
column: Column::new(1, Any::Advice),
|
|
offset: 1,
|
|
}])
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn bad_lookup() {
|
|
const K: u32 = 4;
|
|
|
|
#[derive(Clone)]
|
|
struct FaultyCircuitConfig {
|
|
a: Column<Advice>,
|
|
q: Selector,
|
|
table: TableColumn,
|
|
}
|
|
|
|
struct FaultyCircuit {}
|
|
|
|
impl Circuit<Fp> for FaultyCircuit {
|
|
type Config = FaultyCircuitConfig;
|
|
type FloorPlanner = SimpleFloorPlanner;
|
|
|
|
fn configure(meta: &mut ConstraintSystem<Fp>) -> Self::Config {
|
|
let a = meta.advice_column();
|
|
let q = meta.complex_selector();
|
|
let table = meta.lookup_table_column();
|
|
|
|
meta.lookup(|cells| {
|
|
let a = cells.query_advice(a, Rotation::cur());
|
|
let q = cells.query_selector(q);
|
|
|
|
// If q is enabled, a must be in the table.
|
|
// When q is not enabled, lookup the default value instead.
|
|
let not_q = Expression::Constant(Fp::one()) - q.clone();
|
|
let default = Expression::Constant(Fp::from(2));
|
|
vec![(q * a + not_q * default, table)]
|
|
});
|
|
|
|
FaultyCircuitConfig { a, q, table }
|
|
}
|
|
|
|
fn without_witnesses(&self) -> Self {
|
|
Self {}
|
|
}
|
|
|
|
fn synthesize(
|
|
&self,
|
|
config: Self::Config,
|
|
mut layouter: impl Layouter<Fp>,
|
|
) -> Result<(), Error> {
|
|
layouter.assign_table(
|
|
|| "Doubling table",
|
|
|mut table| {
|
|
(1..(1 << (K - 1)))
|
|
.map(|i| {
|
|
table.assign_cell(
|
|
|| format!("table[{}] = {}", i, 2 * i),
|
|
config.table,
|
|
i - 1,
|
|
|| Value::known(Fp::from(2 * i as u64)),
|
|
)
|
|
})
|
|
.fold(Ok(()), |acc, res| acc.and(res))
|
|
},
|
|
)?;
|
|
|
|
layouter.assign_region(
|
|
|| "Good synthesis",
|
|
|mut region| {
|
|
// Enable the lookup on rows 0 and 1.
|
|
config.q.enable(&mut region, 0)?;
|
|
config.q.enable(&mut region, 1)?;
|
|
|
|
// Assign a = 2 and a = 6.
|
|
region.assign_advice(
|
|
|| "a = 2",
|
|
config.a,
|
|
0,
|
|
|| Value::known(Fp::from(2)),
|
|
)?;
|
|
region.assign_advice(
|
|
|| "a = 6",
|
|
config.a,
|
|
1,
|
|
|| Value::known(Fp::from(6)),
|
|
)?;
|
|
|
|
Ok(())
|
|
},
|
|
)?;
|
|
|
|
layouter.assign_region(
|
|
|| "Faulty synthesis",
|
|
|mut region| {
|
|
// Enable the lookup on rows 0 and 1.
|
|
config.q.enable(&mut region, 0)?;
|
|
config.q.enable(&mut region, 1)?;
|
|
|
|
// Assign a = 4.
|
|
region.assign_advice(
|
|
|| "a = 4",
|
|
config.a,
|
|
0,
|
|
|| Value::known(Fp::from(4)),
|
|
)?;
|
|
|
|
// BUG: Assign a = 5, which doesn't exist in the table!
|
|
region.assign_advice(
|
|
|| "a = 5",
|
|
config.a,
|
|
1,
|
|
|| Value::known(Fp::from(5)),
|
|
)?;
|
|
|
|
Ok(())
|
|
},
|
|
)
|
|
}
|
|
}
|
|
|
|
let prover = MockProver::run(K, &FaultyCircuit {}, vec![]).unwrap();
|
|
assert_eq!(
|
|
prover.verify(),
|
|
Err(vec![VerifyFailure::Lookup {
|
|
lookup_index: 0,
|
|
location: FailureLocation::InRegion {
|
|
region: (2, "Faulty synthesis").into(),
|
|
offset: 1,
|
|
}
|
|
}])
|
|
);
|
|
}
|
|
}
|