Files
pirate-librustzcash/zcash_proofs/src/circuit/sapling.rs
2020-04-23 16:23:24 +12:00

972 lines
34 KiB
Rust

//! The Sapling circuits.
use ff::{Field, PrimeField};
use bellman::{Circuit, ConstraintSystem, SynthesisError};
use zcash_primitives::jubjub::{FixedGenerators, JubjubEngine};
use zcash_primitives::constants;
use zcash_primitives::primitives::{PaymentAddress, ProofGenerationKey, ValueCommitment};
use super::ecc;
use super::pedersen_hash;
use bellman::gadgets::blake2s;
use bellman::gadgets::boolean;
use bellman::gadgets::multipack;
use bellman::gadgets::num;
use bellman::gadgets::Assignment;
pub const TREE_DEPTH: usize = zcash_primitives::sapling::SAPLING_COMMITMENT_TREE_DEPTH;
/// This is an instance of the `Spend` circuit.
pub struct Spend<'a, E: JubjubEngine> {
pub params: &'a E::Params,
/// Pedersen commitment to the value being spent
pub value_commitment: Option<ValueCommitment<E>>,
/// Key required to construct proofs for spending notes
/// for a particular spending key
pub proof_generation_key: Option<ProofGenerationKey<E>>,
/// The payment address associated with the note
pub payment_address: Option<PaymentAddress<E>>,
/// The randomness of the note commitment
pub commitment_randomness: Option<E::Fs>,
/// Re-randomization of the public key
pub ar: Option<E::Fs>,
/// The authentication path of the commitment in the tree
pub auth_path: Vec<Option<(E::Fr, bool)>>,
/// The anchor; the root of the tree. If the note being
/// spent is zero-value, this can be anything.
pub anchor: Option<E::Fr>,
}
/// This is an output circuit instance.
pub struct Output<'a, E: JubjubEngine> {
pub params: &'a E::Params,
/// Pedersen commitment to the value being spent
pub value_commitment: Option<ValueCommitment<E>>,
/// The payment address of the recipient
pub payment_address: Option<PaymentAddress<E>>,
/// The randomness used to hide the note commitment data
pub commitment_randomness: Option<E::Fs>,
/// The ephemeral secret key for DH with recipient
pub esk: Option<E::Fs>,
}
/// Exposes a Pedersen commitment to the value as an
/// input to the circuit
fn expose_value_commitment<E, CS>(
mut cs: CS,
value_commitment: Option<ValueCommitment<E>>,
params: &E::Params,
) -> Result<Vec<boolean::Boolean>, SynthesisError>
where
E: JubjubEngine,
CS: ConstraintSystem<E>,
{
// Booleanize the value into little-endian bit order
let value_bits = boolean::u64_into_boolean_vec_le(
cs.namespace(|| "value"),
value_commitment.as_ref().map(|c| c.value),
)?;
// Compute the note value in the exponent
let value = ecc::fixed_base_multiplication(
cs.namespace(|| "compute the value in the exponent"),
FixedGenerators::ValueCommitmentValue,
&value_bits,
params,
)?;
// Booleanize the randomness. This does not ensure
// the bit representation is "in the field" because
// it doesn't matter for security.
let rcv = boolean::field_into_boolean_vec_le(
cs.namespace(|| "rcv"),
value_commitment.as_ref().map(|c| c.randomness),
)?;
// Compute the randomness in the exponent
let rcv = ecc::fixed_base_multiplication(
cs.namespace(|| "computation of rcv"),
FixedGenerators::ValueCommitmentRandomness,
&rcv,
params,
)?;
// Compute the Pedersen commitment to the value
let cv = value.add(cs.namespace(|| "computation of cv"), &rcv, params)?;
// Expose the commitment as an input to the circuit
cv.inputize(cs.namespace(|| "commitment point"))?;
Ok(value_bits)
}
impl<'a, E: JubjubEngine> Circuit<E> for Spend<'a, E> {
fn synthesize<CS: ConstraintSystem<E>>(self, cs: &mut CS) -> Result<(), SynthesisError> {
// Prover witnesses ak (ensures that it's on the curve)
let ak = ecc::EdwardsPoint::witness(
cs.namespace(|| "ak"),
self.proof_generation_key.as_ref().map(|k| k.ak.clone()),
self.params,
)?;
// There are no sensible attacks on small order points
// of ak (that we're aware of!) but it's a cheap check,
// so we do it.
ak.assert_not_small_order(cs.namespace(|| "ak not small order"), self.params)?;
// Rerandomize ak and expose it as an input to the circuit
{
let ar = boolean::field_into_boolean_vec_le(cs.namespace(|| "ar"), self.ar)?;
// Compute the randomness in the exponent
let ar = ecc::fixed_base_multiplication(
cs.namespace(|| "computation of randomization for the signing key"),
FixedGenerators::SpendingKeyGenerator,
&ar,
self.params,
)?;
let rk = ak.add(cs.namespace(|| "computation of rk"), &ar, self.params)?;
rk.inputize(cs.namespace(|| "rk"))?;
}
// Compute nk = [nsk] ProofGenerationKey
let nk;
{
// Witness nsk as bits
let nsk = boolean::field_into_boolean_vec_le(
cs.namespace(|| "nsk"),
self.proof_generation_key.as_ref().map(|k| k.nsk),
)?;
// NB: We don't ensure that the bit representation of nsk
// is "in the field" (Fs) because it's not used except to
// demonstrate the prover knows it. If they know a
// congruency then that's equivalent.
// Compute nk = [nsk] ProvingPublicKey
nk = ecc::fixed_base_multiplication(
cs.namespace(|| "computation of nk"),
FixedGenerators::ProofGenerationKey,
&nsk,
self.params,
)?;
}
// This is the "viewing key" preimage for CRH^ivk
let mut ivk_preimage = vec![];
// Place ak in the preimage for CRH^ivk
ivk_preimage.extend(ak.repr(cs.namespace(|| "representation of ak"))?);
// This is the nullifier preimage for PRF^nf
let mut nf_preimage = vec![];
// Extend ivk and nf preimages with the representation of
// nk.
{
let repr_nk = nk.repr(cs.namespace(|| "representation of nk"))?;
ivk_preimage.extend(repr_nk.iter().cloned());
nf_preimage.extend(repr_nk);
}
assert_eq!(ivk_preimage.len(), 512);
assert_eq!(nf_preimage.len(), 256);
// Compute the incoming viewing key ivk
let mut ivk = blake2s::blake2s(
cs.namespace(|| "computation of ivk"),
&ivk_preimage,
constants::CRH_IVK_PERSONALIZATION,
)?;
// drop_5 to ensure it's in the field
ivk.truncate(E::Fs::CAPACITY as usize);
// Witness g_d, checking that it's on the curve.
let g_d = {
// This binding is to avoid a weird edge case in Rust's
// ownership/borrowing rules. self is partially moved
// above, but the closure for and_then will have to
// move self (or a reference to self) to reference
// self.params, so we have to copy self.params here.
let params = self.params;
ecc::EdwardsPoint::witness(
cs.namespace(|| "witness g_d"),
self.payment_address.as_ref().and_then(|a| a.g_d(params)),
self.params,
)?
};
// Check that g_d is not small order. Technically, this check
// is already done in the Output circuit, and this proof ensures
// g_d is bound to a product of that check, but for defense in
// depth let's check it anyway. It's cheap.
g_d.assert_not_small_order(cs.namespace(|| "g_d not small order"), self.params)?;
// Compute pk_d = g_d^ivk
let pk_d = g_d.mul(cs.namespace(|| "compute pk_d"), &ivk, self.params)?;
// Compute note contents:
// value (in big endian) followed by g_d and pk_d
let mut note_contents = vec![];
// Handle the value; we'll need it later for the
// dummy input check.
let mut value_num = num::Num::zero();
{
// Get the value in little-endian bit order
let value_bits = expose_value_commitment(
cs.namespace(|| "value commitment"),
self.value_commitment,
self.params,
)?;
// Compute the note's value as a linear combination
// of the bits.
let mut coeff = E::Fr::one();
for bit in &value_bits {
value_num = value_num.add_bool_with_coeff(CS::one(), bit, coeff);
coeff = coeff.double();
}
// Place the value in the note
note_contents.extend(value_bits);
}
// Place g_d in the note
note_contents.extend(g_d.repr(cs.namespace(|| "representation of g_d"))?);
// Place pk_d in the note
note_contents.extend(pk_d.repr(cs.namespace(|| "representation of pk_d"))?);
assert_eq!(
note_contents.len(),
64 + // value
256 + // g_d
256 // p_d
);
// Compute the hash of the note contents
let mut cm = pedersen_hash::pedersen_hash(
cs.namespace(|| "note content hash"),
pedersen_hash::Personalization::NoteCommitment,
&note_contents,
self.params,
)?;
{
// Booleanize the randomness for the note commitment
let rcm = boolean::field_into_boolean_vec_le(
cs.namespace(|| "rcm"),
self.commitment_randomness,
)?;
// Compute the note commitment randomness in the exponent
let rcm = ecc::fixed_base_multiplication(
cs.namespace(|| "computation of commitment randomness"),
FixedGenerators::NoteCommitmentRandomness,
&rcm,
self.params,
)?;
// Randomize the note commitment. Pedersen hashes are not
// themselves hiding commitments.
cm = cm.add(
cs.namespace(|| "randomization of note commitment"),
&rcm,
self.params,
)?;
}
// This will store (least significant bit first)
// the position of the note in the tree, for use
// in nullifier computation.
let mut position_bits = vec![];
// This is an injective encoding, as cur is a
// point in the prime order subgroup.
let mut cur = cm.get_x().clone();
// Ascend the merkle tree authentication path
for (i, e) in self.auth_path.into_iter().enumerate() {
let cs = &mut cs.namespace(|| format!("merkle tree hash {}", i));
// Determines if the current subtree is the "right" leaf at this
// depth of the tree.
let cur_is_right = boolean::Boolean::from(boolean::AllocatedBit::alloc(
cs.namespace(|| "position bit"),
e.map(|e| e.1),
)?);
// Push this boolean for nullifier computation later
position_bits.push(cur_is_right.clone());
// Witness the authentication path element adjacent
// at this depth.
let path_element =
num::AllocatedNum::alloc(cs.namespace(|| "path element"), || Ok(e.get()?.0))?;
// Swap the two if the current subtree is on the right
let (xl, xr) = num::AllocatedNum::conditionally_reverse(
cs.namespace(|| "conditional reversal of preimage"),
&cur,
&path_element,
&cur_is_right,
)?;
// We don't need to be strict, because the function is
// collision-resistant. If the prover witnesses a congruency,
// they will be unable to find an authentication path in the
// tree with high probability.
let mut preimage = vec![];
preimage.extend(xl.to_bits_le(cs.namespace(|| "xl into bits"))?);
preimage.extend(xr.to_bits_le(cs.namespace(|| "xr into bits"))?);
// Compute the new subtree value
cur = pedersen_hash::pedersen_hash(
cs.namespace(|| "computation of pedersen hash"),
pedersen_hash::Personalization::MerkleTree(i),
&preimage,
self.params,
)?
.get_x()
.clone(); // Injective encoding
}
{
let real_anchor_value = self.anchor;
// Allocate the "real" anchor that will be exposed.
let rt = num::AllocatedNum::alloc(cs.namespace(|| "conditional anchor"), || {
Ok(*real_anchor_value.get()?)
})?;
// (cur - rt) * value = 0
// if value is zero, cur and rt can be different
// if value is nonzero, they must be equal
cs.enforce(
|| "conditionally enforce correct root",
|lc| lc + cur.get_variable() - rt.get_variable(),
|lc| lc + &value_num.lc(E::Fr::one()),
|lc| lc,
);
// Expose the anchor
rt.inputize(cs.namespace(|| "anchor"))?;
}
// Compute the cm + g^position for preventing
// faerie gold attacks
let mut rho = cm;
{
// Compute the position in the exponent
let position = ecc::fixed_base_multiplication(
cs.namespace(|| "g^position"),
FixedGenerators::NullifierPosition,
&position_bits,
self.params,
)?;
// Add the position to the commitment
rho = rho.add(
cs.namespace(|| "faerie gold prevention"),
&position,
self.params,
)?;
}
// Let's compute nf = BLAKE2s(nk || rho)
nf_preimage.extend(rho.repr(cs.namespace(|| "representation of rho"))?);
assert_eq!(nf_preimage.len(), 512);
// Compute nf
let nf = blake2s::blake2s(
cs.namespace(|| "nf computation"),
&nf_preimage,
constants::PRF_NF_PERSONALIZATION,
)?;
multipack::pack_into_inputs(cs.namespace(|| "pack nullifier"), &nf)
}
}
impl<'a, E: JubjubEngine> Circuit<E> for Output<'a, E> {
fn synthesize<CS: ConstraintSystem<E>>(self, cs: &mut CS) -> Result<(), SynthesisError> {
// Let's start to construct our note, which contains
// value (big endian)
let mut note_contents = vec![];
// Expose the value commitment and place the value
// in the note.
note_contents.extend(expose_value_commitment(
cs.namespace(|| "value commitment"),
self.value_commitment,
self.params,
)?);
// Let's deal with g_d
{
let params = self.params;
// Prover witnesses g_d, ensuring it's on the
// curve.
let g_d = ecc::EdwardsPoint::witness(
cs.namespace(|| "witness g_d"),
self.payment_address.as_ref().and_then(|a| a.g_d(params)),
self.params,
)?;
// g_d is ensured to be large order. The relationship
// between g_d and pk_d ultimately binds ivk to the
// note. If this were a small order point, it would
// not do this correctly, and the prover could
// double-spend by finding random ivk's that satisfy
// the relationship.
//
// Further, if it were small order, epk would be
// small order too!
g_d.assert_not_small_order(cs.namespace(|| "g_d not small order"), self.params)?;
// Extend our note contents with the representation of
// g_d.
note_contents.extend(g_d.repr(cs.namespace(|| "representation of g_d"))?);
// Booleanize our ephemeral secret key
let esk = boolean::field_into_boolean_vec_le(cs.namespace(|| "esk"), self.esk)?;
// Create the ephemeral public key from g_d.
let epk = g_d.mul(cs.namespace(|| "epk computation"), &esk, self.params)?;
// Expose epk publicly.
epk.inputize(cs.namespace(|| "epk"))?;
}
// Now let's deal with pk_d. We don't do any checks and
// essentially allow the prover to witness any 256 bits
// they would like.
{
// Just grab pk_d from the witness
let pk_d = self.payment_address.as_ref().map(|e| e.pk_d().to_xy());
// Witness the y-coordinate, encoded as little
// endian bits (to match the representation)
let y_contents = boolean::field_into_boolean_vec_le(
cs.namespace(|| "pk_d bits of y"),
pk_d.map(|e| e.1),
)?;
// Witness the sign bit
let sign_bit = boolean::Boolean::from(boolean::AllocatedBit::alloc(
cs.namespace(|| "pk_d bit of x"),
pk_d.map(|e| e.0.is_odd()),
)?);
// Extend the note with pk_d representation
note_contents.extend(y_contents);
note_contents.push(sign_bit);
}
assert_eq!(
note_contents.len(),
64 + // value
256 + // g_d
256 // pk_d
);
// Compute the hash of the note contents
let mut cm = pedersen_hash::pedersen_hash(
cs.namespace(|| "note content hash"),
pedersen_hash::Personalization::NoteCommitment,
&note_contents,
self.params,
)?;
{
// Booleanize the randomness
let rcm = boolean::field_into_boolean_vec_le(
cs.namespace(|| "rcm"),
self.commitment_randomness,
)?;
// Compute the note commitment randomness in the exponent
let rcm = ecc::fixed_base_multiplication(
cs.namespace(|| "computation of commitment randomness"),
FixedGenerators::NoteCommitmentRandomness,
&rcm,
self.params,
)?;
// Randomize our note commitment
cm = cm.add(
cs.namespace(|| "randomization of note commitment"),
&rcm,
self.params,
)?;
}
// Only the x-coordinate of the output is revealed,
// since we know it is prime order, and we know that
// the x-coordinate is an injective encoding for
// prime-order elements.
cm.get_x().inputize(cs.namespace(|| "commitment"))?;
Ok(())
}
}
#[test]
fn test_input_circuit_with_bls12_381() {
use bellman::gadgets::test::*;
use ff::{BitIterator, Field};
use pairing::bls12_381::*;
use rand_core::{RngCore, SeedableRng};
use rand_xorshift::XorShiftRng;
use zcash_primitives::{
jubjub::{edwards, fs, JubjubBls12},
pedersen_hash,
primitives::{Diversifier, Note, ProofGenerationKey},
};
let params = &JubjubBls12::new();
let rng = &mut XorShiftRng::from_seed([
0x58, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
0xe5,
]);
let tree_depth = 32;
for _ in 0..10 {
let value_commitment = ValueCommitment {
value: rng.next_u64(),
randomness: fs::Fs::random(rng),
};
let nsk = fs::Fs::random(rng);
let ak = edwards::Point::rand(rng, params).mul_by_cofactor(params);
let proof_generation_key = ProofGenerationKey {
ak: ak.clone(),
nsk: nsk.clone(),
};
let viewing_key = proof_generation_key.to_viewing_key(params);
let payment_address;
loop {
let diversifier = {
let mut d = [0; 11];
rng.fill_bytes(&mut d);
Diversifier(d)
};
if let Some(p) = viewing_key.to_payment_address(diversifier, params) {
payment_address = p;
break;
}
}
let g_d = payment_address.diversifier().g_d(params).unwrap();
let commitment_randomness = fs::Fs::random(rng);
let auth_path = vec![Some((Fr::random(rng), rng.next_u32() % 2 != 0)); tree_depth];
let ar = fs::Fs::random(rng);
{
let rk = viewing_key.rk(ar, params).to_xy();
let expected_value_cm = value_commitment.cm(params).to_xy();
let note = Note {
value: value_commitment.value,
g_d: g_d.clone(),
pk_d: payment_address.pk_d().clone(),
r: commitment_randomness.clone(),
};
let mut position = 0u64;
let cm: Fr = note.cm(params);
let mut cur = cm.clone();
for (i, val) in auth_path.clone().into_iter().enumerate() {
let (uncle, b) = val.unwrap();
let mut lhs = cur;
let mut rhs = uncle;
if b {
::std::mem::swap(&mut lhs, &mut rhs);
}
let mut lhs: Vec<bool> = BitIterator::<u64, _>::new(lhs.into_repr()).collect();
let mut rhs: Vec<bool> = BitIterator::<u64, _>::new(rhs.into_repr()).collect();
lhs.reverse();
rhs.reverse();
cur = pedersen_hash::pedersen_hash::<Bls12, _>(
pedersen_hash::Personalization::MerkleTree(i),
lhs.into_iter()
.take(Fr::NUM_BITS as usize)
.chain(rhs.into_iter().take(Fr::NUM_BITS as usize)),
params,
)
.to_xy()
.0;
if b {
position |= 1 << i;
}
}
let expected_nf = note.nf(&viewing_key, position, params);
let expected_nf = multipack::bytes_to_bits_le(&expected_nf);
let expected_nf = multipack::compute_multipacking::<Bls12>(&expected_nf);
assert_eq!(expected_nf.len(), 2);
let mut cs = TestConstraintSystem::<Bls12>::new();
let instance = Spend {
params,
value_commitment: Some(value_commitment.clone()),
proof_generation_key: Some(proof_generation_key.clone()),
payment_address: Some(payment_address.clone()),
commitment_randomness: Some(commitment_randomness),
ar: Some(ar),
auth_path: auth_path.clone(),
anchor: Some(cur),
};
instance.synthesize(&mut cs).unwrap();
assert!(cs.is_satisfied());
assert_eq!(cs.num_constraints(), 98777);
assert_eq!(
cs.hash(),
"d37c738e83df5d9b0bb6495ac96abf21bcb2697477e2c15c2c7916ff7a3b6a89"
);
assert_eq!(cs.get("randomization of note commitment/x3/num"), cm);
assert_eq!(cs.num_inputs(), 8);
assert_eq!(cs.get_input(0, "ONE"), Fr::one());
assert_eq!(cs.get_input(1, "rk/x/input variable"), rk.0);
assert_eq!(cs.get_input(2, "rk/y/input variable"), rk.1);
assert_eq!(
cs.get_input(3, "value commitment/commitment point/x/input variable"),
expected_value_cm.0
);
assert_eq!(
cs.get_input(4, "value commitment/commitment point/y/input variable"),
expected_value_cm.1
);
assert_eq!(cs.get_input(5, "anchor/input variable"), cur);
assert_eq!(cs.get_input(6, "pack nullifier/input 0"), expected_nf[0]);
assert_eq!(cs.get_input(7, "pack nullifier/input 1"), expected_nf[1]);
}
}
}
#[test]
fn test_input_circuit_with_bls12_381_external_test_vectors() {
use bellman::gadgets::test::*;
use ff::{BitIterator, Field};
use pairing::bls12_381::*;
use rand_core::{RngCore, SeedableRng};
use rand_xorshift::XorShiftRng;
use zcash_primitives::{
jubjub::{edwards, fs, JubjubBls12},
pedersen_hash,
primitives::{Diversifier, Note, ProofGenerationKey},
};
let params = &JubjubBls12::new();
let rng = &mut XorShiftRng::from_seed([
0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
0xe5,
]);
let tree_depth = 32;
let expected_cm_xs = vec![
"43821661663052659750276289184181083197337192946256245809816728673021647664276",
"7220807656052227578299730541645543434083158611414003423211850718229633594616",
"13239753550660714843257636471668037031928211668773449453628093339627668081697",
"10900524635678389360790699587556574797582192824300145558807405770494079767974",
"1411013767457690636461779630023011774660680126764323588543800715293173598850",
"32334206652383066267661379202183359608706535021387905923603014648832344657662",
"20206750741605167608500278423400565295188703622528437817438897624149653579380",
"46716485782200334735478719487356079850582051575003452698983255860512578229998",
"31221372899739042781372142393132358519434268512685538373976981051223051220367",
"18269767207277008186871145355531741929166733260352590789136389380124992250945",
];
let expected_cm_ys = vec![
"27630722367128086497290371604583225252915685718989450292520883698391703910",
"23310648738313092772044712773481584369462075017189681529702825235349449805260",
"25709635353183537915646348052945798827495141780341329896098121888376871589480",
"10516315852014492141081718791576479298042117442649432716255936672048164184691",
"23970713991179488695004801139667700217127937225554773561645815034212389459772",
"3256052161046564597126736968199320852691566092694819239485673781545479548450",
"18887250722195819674378865377623103071236046274361890247643850134985809137409",
"36501156873031641173054592888886902104303750771545647842488588827138867116570",
"21927526310070011864833939629345235038589128172309792087590183778192091594775",
"32959334601512756708397683646222389414681003290313255304927423560477040775488",
];
for i in 0..10 {
let value_commitment = ValueCommitment {
value: i,
randomness: fs::Fs::from_str(&(1000 * (i + 1)).to_string()).unwrap(),
};
let nsk = fs::Fs::random(rng);
let ak = edwards::Point::rand(rng, params).mul_by_cofactor(params);
let proof_generation_key = ProofGenerationKey {
ak: ak.clone(),
nsk: nsk.clone(),
};
let viewing_key = proof_generation_key.to_viewing_key(params);
let payment_address;
loop {
let diversifier = {
let mut d = [0; 11];
rng.fill_bytes(&mut d);
Diversifier(d)
};
if let Some(p) = viewing_key.to_payment_address(diversifier, params) {
payment_address = p;
break;
}
}
let g_d = payment_address.diversifier().g_d(params).unwrap();
let commitment_randomness = fs::Fs::random(rng);
let auth_path = vec![Some((Fr::random(rng), rng.next_u32() % 2 != 0)); tree_depth];
let ar = fs::Fs::random(rng);
{
let rk = viewing_key.rk(ar, params).to_xy();
let expected_value_cm = value_commitment.cm(params).to_xy();
assert_eq!(
expected_value_cm.0,
Fr::from_str(&expected_cm_xs[i as usize]).unwrap()
);
assert_eq!(
expected_value_cm.1,
Fr::from_str(&expected_cm_ys[i as usize]).unwrap()
);
let note = Note {
value: value_commitment.value,
g_d: g_d.clone(),
pk_d: payment_address.pk_d().clone(),
r: commitment_randomness.clone(),
};
let mut position = 0u64;
let cm: Fr = note.cm(params);
let mut cur = cm.clone();
for (i, val) in auth_path.clone().into_iter().enumerate() {
let (uncle, b) = val.unwrap();
let mut lhs = cur;
let mut rhs = uncle;
if b {
::std::mem::swap(&mut lhs, &mut rhs);
}
let mut lhs: Vec<bool> = BitIterator::<u64, _>::new(lhs.into_repr()).collect();
let mut rhs: Vec<bool> = BitIterator::<u64, _>::new(rhs.into_repr()).collect();
lhs.reverse();
rhs.reverse();
cur = pedersen_hash::pedersen_hash::<Bls12, _>(
pedersen_hash::Personalization::MerkleTree(i),
lhs.into_iter()
.take(Fr::NUM_BITS as usize)
.chain(rhs.into_iter().take(Fr::NUM_BITS as usize)),
params,
)
.to_xy()
.0;
if b {
position |= 1 << i;
}
}
let expected_nf = note.nf(&viewing_key, position, params);
let expected_nf = multipack::bytes_to_bits_le(&expected_nf);
let expected_nf = multipack::compute_multipacking::<Bls12>(&expected_nf);
assert_eq!(expected_nf.len(), 2);
let mut cs = TestConstraintSystem::<Bls12>::new();
let instance = Spend {
params: params,
value_commitment: Some(value_commitment.clone()),
proof_generation_key: Some(proof_generation_key.clone()),
payment_address: Some(payment_address.clone()),
commitment_randomness: Some(commitment_randomness),
ar: Some(ar),
auth_path: auth_path.clone(),
anchor: Some(cur),
};
instance.synthesize(&mut cs).unwrap();
assert!(cs.is_satisfied());
assert_eq!(cs.num_constraints(), 98777);
assert_eq!(
cs.hash(),
"d37c738e83df5d9b0bb6495ac96abf21bcb2697477e2c15c2c7916ff7a3b6a89"
);
assert_eq!(cs.get("randomization of note commitment/x3/num"), cm);
assert_eq!(cs.num_inputs(), 8);
assert_eq!(cs.get_input(0, "ONE"), Fr::one());
assert_eq!(cs.get_input(1, "rk/x/input variable"), rk.0);
assert_eq!(cs.get_input(2, "rk/y/input variable"), rk.1);
assert_eq!(
cs.get_input(3, "value commitment/commitment point/x/input variable"),
expected_value_cm.0
);
assert_eq!(
cs.get_input(4, "value commitment/commitment point/y/input variable"),
expected_value_cm.1
);
assert_eq!(cs.get_input(5, "anchor/input variable"), cur);
assert_eq!(cs.get_input(6, "pack nullifier/input 0"), expected_nf[0]);
assert_eq!(cs.get_input(7, "pack nullifier/input 1"), expected_nf[1]);
}
}
}
#[test]
fn test_output_circuit_with_bls12_381() {
use bellman::gadgets::test::*;
use ff::Field;
use pairing::bls12_381::*;
use rand_core::{RngCore, SeedableRng};
use rand_xorshift::XorShiftRng;
use zcash_primitives::{
jubjub::{edwards, fs, JubjubBls12},
primitives::{Diversifier, ProofGenerationKey},
};
let params = &JubjubBls12::new();
let rng = &mut XorShiftRng::from_seed([
0x58, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
0xe5,
]);
for _ in 0..100 {
let value_commitment = ValueCommitment {
value: rng.next_u64(),
randomness: fs::Fs::random(rng),
};
let nsk = fs::Fs::random(rng);
let ak = edwards::Point::rand(rng, params).mul_by_cofactor(params);
let proof_generation_key = ProofGenerationKey {
ak: ak.clone(),
nsk: nsk.clone(),
};
let viewing_key = proof_generation_key.to_viewing_key(params);
let payment_address;
loop {
let diversifier = {
let mut d = [0; 11];
rng.fill_bytes(&mut d);
Diversifier(d)
};
if let Some(p) = viewing_key.to_payment_address(diversifier, params) {
payment_address = p;
break;
}
}
let commitment_randomness = fs::Fs::random(rng);
let esk = fs::Fs::random(rng);
{
let mut cs = TestConstraintSystem::<Bls12>::new();
let instance = Output {
params,
value_commitment: Some(value_commitment.clone()),
payment_address: Some(payment_address.clone()),
commitment_randomness: Some(commitment_randomness),
esk: Some(esk.clone()),
};
instance.synthesize(&mut cs).unwrap();
assert!(cs.is_satisfied());
assert_eq!(cs.num_constraints(), 7827);
assert_eq!(
cs.hash(),
"c26d5cdfe6ccd65c03390902c02e11393ea6bb96aae32a7f2ecb12eb9103faee"
);
let expected_cm = payment_address
.create_note(value_commitment.value, commitment_randomness, params)
.expect("should be valid")
.cm(params);
let expected_value_cm = value_commitment.cm(params).to_xy();
let expected_epk = payment_address
.g_d(params)
.expect("should be valid")
.mul(esk, params);
let expected_epk_xy = expected_epk.to_xy();
assert_eq!(cs.num_inputs(), 6);
assert_eq!(cs.get_input(0, "ONE"), Fr::one());
assert_eq!(
cs.get_input(1, "value commitment/commitment point/x/input variable"),
expected_value_cm.0
);
assert_eq!(
cs.get_input(2, "value commitment/commitment point/y/input variable"),
expected_value_cm.1
);
assert_eq!(cs.get_input(3, "epk/x/input variable"), expected_epk_xy.0);
assert_eq!(cs.get_input(4, "epk/y/input variable"), expected_epk_xy.1);
assert_eq!(cs.get_input(5, "commitment/input variable"), expected_cm);
}
}
}