forked from TrueCloudLab/neoneo-go
Merge pull request #3234 from nspcc-dev/add-response-source
examples: improve cubic circuit documentation
This commit is contained in:
Roman Khimov
GitHub
commit
e8e964e3da
2 changed files with 33 additions and 15 deletions
|
|
@ -31,20 +31,25 @@ to organize the ceremony and generate proving and verifying keys for a circuit.
|
|||
However, both phases take a significant amount of time and computations to be
|
||||
performed. Luckily for the developers, it is possible to omit a curve-specific
|
||||
part of the MPC and reuse the existing results of Phase 1 got from a trusted
|
||||
source, e.g. from [Powers of Tau ceremony](https://github.com/filecoin-project/powersoftau/)
|
||||
held by the [Filecoin project](https://github.com/filecoin-project/phase2-attestations#phase1).
|
||||
source, e.g. from [Zcash PowersOfTau](https://github.com/ZcashFoundation/powersoftau-attestations)
|
||||
held by the [Zcash Foundation](https://github.com/ZcashFoundation).
|
||||
`TestCubicCircuit_EndToEnd_Prod` test of the current circuit example demonstrates
|
||||
how to use the `response` output file from the Phase 1 of the Filecoin's Powers
|
||||
of Tau ceremony for BLS12-381 curve:
|
||||
* [`response8`](./response8) file is the response output from the [Powers of Tau ceremony](https://github.com/filecoin-project/powersoftau/)
|
||||
with the `REQUIRED_POWER` set to 8 (to reduce computations and response file size)
|
||||
that was run locally with the help of [testing script](https://github.com/filecoin-project/powersoftau/blob/master/test.sh).
|
||||
* [`response8`](./response8) file is the response output from the ceremony that was run locally
|
||||
based on the [Filecoin Powers of Tau](https://github.com/filecoin-project/powersoftau/)
|
||||
with the `REQUIRED_POWER` set to 8 (to reduce computations and response file size).
|
||||
The ceremony itself was run with the help of [testing script](https://github.com/filecoin-project/powersoftau/blob/master/test.sh).
|
||||
To get the response file for a production environment, the user has two options:
|
||||
1. Organize his own ceremony with required number of powers following the
|
||||
[guide](https://github.com/filecoin-project/powersoftau/tree/master#instructions)
|
||||
from the source repo.
|
||||
2. Download the existing suitable `response` file from the
|
||||
[attestations page](https://github.com/arielgabizon/perpetualpowersoftau#perpetual-powers-of-tau-for-bls381).
|
||||
from the ceremony source repo.
|
||||
2. Download the existing suitable `response` file from the trusted existing ceremony.
|
||||
Please, be careful while choosing `response` file and ensure that it has enough
|
||||
powers computed (at least as much as the number of the circuit's constraints requires).
|
||||
Example of suitable ceremonies:
|
||||
* Zcash Powers Of Tau [attestations page](https://github.com/ZcashFoundation/powersoftau-attestations) (up to 2^21)
|
||||
* Filecoin Perpetual Powers Of Tau [attestations page](https://github.com/arielgabizon/perpetualpowersoftau#perpetual-powers-of-tau-for-bls381) (up to 2^27)
|
||||
* [main_test](./main_test.go) contains the `TestCubicCircuit_EndToEnd_Prod` test
|
||||
itself and demonstrates how to properly initialize Phase 2 based on the given
|
||||
response file and make some dummy contributions into it.
|
||||
|
|
|
|||
|
|
@ -1,6 +1,7 @@
|
|||
package cubic
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"math"
|
||||
"os"
|
||||
"path/filepath"
|
||||
|
|
@ -156,6 +157,12 @@ func TestCubicCircuit_EndToEnd(t *testing.T) {
|
|||
// result for proving/verifying keys generation and demonstrates how to contribute
|
||||
// some randomness into it.
|
||||
func TestCubicCircuit_EndToEnd_Prod(t *testing.T) {
|
||||
const (
|
||||
// Response file generated locally for 2^8 powers.
|
||||
pathToResponseFile = "./response8"
|
||||
// The order of Powers of Tau ceremony, it depends on the response file.
|
||||
orderOfResponseFile = 8
|
||||
)
|
||||
var (
|
||||
circuit CubicCircuit
|
||||
assignment = CubicCircuit{X: 3, Y: 35}
|
||||
|
|
@ -166,8 +173,10 @@ func TestCubicCircuit_EndToEnd_Prod(t *testing.T) {
|
|||
require.NoError(t, err)
|
||||
|
||||
// Setup (groth16 zkSNARK), use MPC-based solution for proving and verifying
|
||||
// keys generation.
|
||||
pk, vk := setup(t, ccs, "./response8", 8) // the order of Powers of Tau ceremony, depends on the response file.
|
||||
// keys generation. Please, be careful while adopting this code for your circuit.
|
||||
// Ensure that response file that you've provided contains enough powers computed
|
||||
// so that the number of constraints in your circuit can be handled.
|
||||
pk, vk := setup(t, ccs, pathToResponseFile, orderOfResponseFile)
|
||||
|
||||
// Intermediate step: witness definition.
|
||||
witness, err := frontend.NewWitness(&assignment, ecc.BLS12_381.ScalarField())
|
||||
|
|
@ -262,20 +271,21 @@ func setup(t *testing.T, ccs constraint.ConstraintSystem, phase1ResponsePath str
|
|||
beta_coef_g1 := make([]curve.G1Affine, inN)
|
||||
|
||||
// Accumulator serialization: https://github.com/filecoin-project/powersoftau/blob/ab8f85c28f04af5a99cfcc93a3b1f74c06f94105/src/accumulator.rs#L111
|
||||
errMessage := fmt.Sprintf("ensure your response file contains exactly 2^%d powers of tau for BLS12-381 curve", inPow)
|
||||
for i := range coef_g1 {
|
||||
require.NoError(t, dec.Decode(&coef_g1[i]))
|
||||
require.NoError(t, dec.Decode(&coef_g1[i]), errMessage)
|
||||
}
|
||||
for i := range coef_g2 {
|
||||
require.NoError(t, dec.Decode(&coef_g2[i]))
|
||||
require.NoError(t, dec.Decode(&coef_g2[i]), errMessage)
|
||||
}
|
||||
for i := range alpha_coef_g1 {
|
||||
require.NoError(t, dec.Decode(&alpha_coef_g1[i]))
|
||||
require.NoError(t, dec.Decode(&alpha_coef_g1[i]), errMessage)
|
||||
}
|
||||
for i := range beta_coef_g1 {
|
||||
require.NoError(t, dec.Decode(&beta_coef_g1[i]))
|
||||
require.NoError(t, dec.Decode(&beta_coef_g1[i]), errMessage)
|
||||
}
|
||||
beta_g2 := &curve.G2Affine{}
|
||||
require.NoError(t, dec.Decode(beta_g2))
|
||||
require.NoError(t, dec.Decode(beta_g2), errMessage)
|
||||
|
||||
// Transform (take exactly those number of powers that needed for the given number of constraints).
|
||||
var (
|
||||
|
|
@ -286,6 +296,9 @@ func setup(t *testing.T, ccs constraint.ConstraintSystem, phase1ResponsePath str
|
|||
}
|
||||
outN := int64(math.Pow(2, float64(outPow)))
|
||||
|
||||
if len(coef_g1) < int(2*outN-1) {
|
||||
t.Fatalf("number of circuit constraints is too large for the provided response file: nbConstraints is %d, required at least %d powers to be computed", numConstraints, outN)
|
||||
}
|
||||
srs1 := mpcsetup.Phase1{}
|
||||
srs1.Parameters.G1.Tau = coef_g1[:2*outN-1] // outN + (outN-1)
|
||||
srs1.Parameters.G2.Tau = coef_g2[:outN] // outN
|
||||
|
|
|
|||
Loading…
Reference in a new issue