Go Ethereum + Precompiled Contract(MiMC7, Poseidon)

Official Golang implementation of the Ethereum protocol.

MiMC

MiMC7 is mapped to Opcode 0x13.
Detail MiMC protocol : https://eprint.iacr.org/2016/492.pdf
Detail MiMC7 protocol : https://iden3-docs.readthedocs.io/en/latest/_downloads/a04267077fb3fdbf2b608e014706e004/Ed-DSA.pdf
MiMC7 algorithm :

SEED = keccak256("mimc7_seed")
ORDER = 21888242871839275222246405745257275088548364400416034343698204186575808495617

function MiMC7(inputs)
  if len(inputs) <= 1 then
    output = mimc7round(inputs[0], inputsinputs[0])
  else
    output = input[0]
    for i = 1 to i < len(inputs) do
      output = mimc7round(output, input[i])
    endfor
  endif
  return output

function mimc7round(m, key)
  rc = keccak256(SEED)
  c = (m + key)^7 mod ORDER // round 1
  for i = 2 to i < 92 do    // round 2 ~ 91
    c = (c + key + rc)^7 mod ORDER
    rc = keccak256(rc)
  endfor
  output = (c + key + m + key) mod ORDER
  return output

Poseidon

Poseidon is mapped to Opcode 0x14.
The Poseidon protocol referred to https://github.com/iden3/go-iden3-crypto/tree/master/poseidon

Building the source

For prerequisites and detailed build instructions please read the Installation Instructions.

Building geth requires both a Go (version 1.16 or later) and a C compiler. You can install them using your favourite package manager. Once the dependencies are installed, run

make geth

or, to build the full suite of utilities:

make all

Running geth

To do
First setup & start :

bash script.sh setup start

Restart Geth :

bash script.sh start

Attach Geth :

bash script.sh console

Stop Geth :

bash script.sh stop

View log :

bash script.sh log

Geth Option

If modify Geth's options, change go-ethereum/genesis & go-ethereum/script.sh files.
The default options are:

Command	Description
chainId	2757
http.corsdomain	*
http.port	8545
http.addr	0.0.0.0
http.api	admin,eth,debug,miner,net,txpool,personal,web3
ws.corsdomain	*
ws.addr	0.0.0.0
ws.port	8545
ws.api	admin,eth,debug,miner,net,txpool,personal,web3

How to Use PreCompiled Contract MiMC7 in Solidity

The input data must padded the remaining left side of 32bytes to "0". (ex 0x01 -> 0x0000000000000000000000000000000000000000000000000000000000000001)
If solidity version order than v0.5.0, use "gas" instead of "gas()" as the first factor in the call function.

pragma solidity >=0.5.0
function callmimc(bytes32[] memory data) public returns (bytes32 result) {
  uint256 len = data.length*32;
  assembly {
    let memPtr := mload(0x40)
      let success := call(gas(), 0x13, 0, add(data, 0x20), len, memPtr, 0x20)
      //solc -v < 0.5.0    let success := call(gas, 0x13, 0, add(data, 0x20), len, memPtr, 0x20)
      switch success
      case 0 {
        revert(0,0)
      } default {
        result := mload(memPtr)
      }
  }
}

How to Use PreCompiled Contract Poseidon in Solidity

The input data must padded the remaining left side of 32bytes to "0". (ex 0x01 -> 0x0000000000000000000000000000000000000000000000000000000000000001)
If solidity version order than v0.5.0, use "gas" instead of "gas()" as the first factor in the call function.

pragma solidity >=0.5.0
function callposeidon(bytes32[] memory data) public returns (bytes32 result) {
  uint256 len = data.length*32;
  assembly {
    let memPtr := mload(0x40)
      let success := call(gas(), 0x14, 0, add(data, 0x20), len, memPtr, 0x20)
      //let success := call(gas, 0x14, 0, add(data, 0x20), len, memPtr, 0x20)
      switch success
      case 0 {
        revert(0,0)
      } default {
        result := mload(memPtr)
      }
  }
}