github.com/klaytn/klaytn@v1.12.1/crypto/kzg4844/kzg4844_ckzg_cgo.go (about)

     1  // Modifications Copyright 2023 The klaytn Authors
     2  // Copyright 2023 The go-ethereum Authors
     3  // This file is part of the go-ethereum library.
     4  //
     5  // The go-ethereum library is free software: you can redistribute it and/or modify
     6  // it under the terms of the GNU Lesser General Public License as published by
     7  // the Free Software Foundation, either version 3 of the License, or
     8  // (at your option) any later version.
     9  //
    10  // The go-ethereum library is distributed in the hope that it will be useful,
    11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    13  // GNU Lesser General Public License for more details.
    14  //
    15  // You should have received a copy of the GNU Lesser General Public License
    16  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    17  //
    18  // This file is derived from crypto/kzg4844/kzg4844_ckzg_cgo.go (2023/11/14).
    19  // Modified and improved for the klaytn development.
    20  
    21  //go:build ckzg && !nacl && !js && cgo && !gofuzz
    22  
    23  package kzg4844
    24  
    25  import (
    26  	"encoding/json"
    27  	"errors"
    28  	"sync"
    29  
    30  	gokzg4844 "github.com/crate-crypto/go-kzg-4844"
    31  	ckzg4844 "github.com/ethereum/c-kzg-4844/bindings/go"
    32  	"github.com/klaytn/klaytn/common/hexutil"
    33  )
    34  
    35  // ckzgAvailable signals whether the library was compiled into Geth.
    36  const ckzgAvailable = true
    37  
    38  // ckzgIniter ensures that we initialize the KZG library once before using it.
    39  var ckzgIniter sync.Once
    40  
    41  // ckzgInit initializes the KZG library with the provided trusted setup.
    42  func ckzgInit() {
    43  	config, err := content.ReadFile("trusted_setup.json")
    44  	if err != nil {
    45  		panic(err)
    46  	}
    47  	params := new(gokzg4844.JSONTrustedSetup)
    48  	if err = json.Unmarshal(config, params); err != nil {
    49  		panic(err)
    50  	}
    51  	if err = gokzg4844.CheckTrustedSetupIsWellFormed(params); err != nil {
    52  		panic(err)
    53  	}
    54  	g1s := make([]byte, len(params.SetupG1Lagrange)*(len(params.SetupG1Lagrange[0])-2)/2)
    55  	for i, g1 := range params.SetupG1Lagrange {
    56  		copy(g1s[i*(len(g1)-2)/2:], hexutil.MustDecode(g1))
    57  	}
    58  	g2s := make([]byte, len(params.SetupG2)*(len(params.SetupG2[0])-2)/2)
    59  	for i, g2 := range params.SetupG2 {
    60  		copy(g2s[i*(len(g2)-2)/2:], hexutil.MustDecode(g2))
    61  	}
    62  	if err = ckzg4844.LoadTrustedSetup(g1s, g2s); err != nil {
    63  		panic(err)
    64  	}
    65  }
    66  
    67  // ckzgBlobToCommitment creates a small commitment out of a data blob.
    68  func ckzgBlobToCommitment(blob Blob) (Commitment, error) {
    69  	ckzgIniter.Do(ckzgInit)
    70  
    71  	commitment, err := ckzg4844.BlobToKZGCommitment((ckzg4844.Blob)(blob))
    72  	if err != nil {
    73  		return Commitment{}, err
    74  	}
    75  	return (Commitment)(commitment), nil
    76  }
    77  
    78  // ckzgComputeProof computes the KZG proof at the given point for the polynomial
    79  // represented by the blob.
    80  func ckzgComputeProof(blob Blob, point Point) (Proof, Claim, error) {
    81  	ckzgIniter.Do(ckzgInit)
    82  
    83  	proof, claim, err := ckzg4844.ComputeKZGProof((ckzg4844.Blob)(blob), (ckzg4844.Bytes32)(point))
    84  	if err != nil {
    85  		return Proof{}, Claim{}, err
    86  	}
    87  	return (Proof)(proof), (Claim)(claim), nil
    88  }
    89  
    90  // ckzgVerifyProof verifies the KZG proof that the polynomial represented by the blob
    91  // evaluated at the given point is the claimed value.
    92  func ckzgVerifyProof(commitment Commitment, point Point, claim Claim, proof Proof) error {
    93  	ckzgIniter.Do(ckzgInit)
    94  
    95  	valid, err := ckzg4844.VerifyKZGProof((ckzg4844.Bytes48)(commitment), (ckzg4844.Bytes32)(point), (ckzg4844.Bytes32)(claim), (ckzg4844.Bytes48)(proof))
    96  	if err != nil {
    97  		return err
    98  	}
    99  	if !valid {
   100  		return errors.New("invalid proof")
   101  	}
   102  	return nil
   103  }
   104  
   105  // ckzgComputeBlobProof returns the KZG proof that is used to verify the blob against
   106  // the commitment.
   107  //
   108  // This method does not verify that the commitment is correct with respect to blob.
   109  func ckzgComputeBlobProof(blob Blob, commitment Commitment) (Proof, error) {
   110  	ckzgIniter.Do(ckzgInit)
   111  
   112  	proof, err := ckzg4844.ComputeBlobKZGProof((ckzg4844.Blob)(blob), (ckzg4844.Bytes48)(commitment))
   113  	if err != nil {
   114  		return Proof{}, err
   115  	}
   116  	return (Proof)(proof), nil
   117  }
   118  
   119  // ckzgVerifyBlobProof verifies that the blob data corresponds to the provided commitment.
   120  func ckzgVerifyBlobProof(blob Blob, commitment Commitment, proof Proof) error {
   121  	ckzgIniter.Do(ckzgInit)
   122  
   123  	valid, err := ckzg4844.VerifyBlobKZGProof((ckzg4844.Blob)(blob), (ckzg4844.Bytes48)(commitment), (ckzg4844.Bytes48)(proof))
   124  	if err != nil {
   125  		return err
   126  	}
   127  	if !valid {
   128  		return errors.New("invalid proof")
   129  	}
   130  	return nil
   131  }