1package eth
  2
  3import (
  4	"encoding/hex"
  5	"fmt"
  6	"math/big"
  7	"net/http"
  8	"strconv"
  9	"strings"
 10
 11	ethCommon "github.com/ethereum/go-ethereum/common"
 12	"golang.org/x/crypto/sha3"
 13)
 14
 15func addBlock(url string) {
 16	method := "POST"
 17
 18	payload := strings.NewReader("{\n    \"jsonrpc\":\"2.0\",\n    \"method\":\"evm_mine\",\n    \"params\":[],\n    \"id\":1\n}")
 19
 20	client := &http.Client{}
 21	req, err := http.NewRequest(method, url, payload)
 22
 23	if err != nil {
 24		fmt.Println(err)
 25	}
 26	req.Header.Add("Content-Type", "application/json")
 27
 28	res, err := client.Do(req)
 29	if err != nil {
 30		fmt.Println(err)
 31	}
 32	defer func() {
 33		if err := res.Body.Close(); err != nil {
 34			fmt.Println("Error when closing:", err)
 35		}
 36	}()
 37}
 38
 39func addBlocks(numBlocks int64, url string) {
 40	for i := int64(0); i < numBlocks; i++ {
 41		addBlock(url)
 42	}
 43}
 44
 45func addTime(seconds float64, url string) {
 46	secondsStr := strconv.FormatFloat(seconds, 'E', -1, 32)
 47
 48	method := "POST"
 49	payload := strings.NewReader("{\n    \"jsonrpc\":\"2.0\",\n    \"method\":\"evm_increaseTime\",\n    \"params\":[" + secondsStr + "],\n    \"id\":1\n}")
 50
 51	client := &http.Client{}
 52	req, err := http.NewRequest(method, url, payload)
 53
 54	if err != nil {
 55		fmt.Println(err)
 56	}
 57	req.Header.Add("Content-Type", "application/json")
 58
 59	res, err := client.Do(req)
 60	if err != nil {
 61		fmt.Println(err)
 62	}
 63	defer func() {
 64		if err := res.Body.Close(); err != nil {
 65			fmt.Println("Error when closing:", err)
 66		}
 67	}()
 68}
 69
 70func createPermitDigest(tokenAddr, owner, spender ethCommon.Address, chainID, value, nonce, deadline *big.Int, tokenName string) ([]byte, error) {
 71	abiPermit := []byte("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")
 72	hashPermit := sha3.NewLegacyKeccak256()
 73	hashPermit.Write(abiPermit)
 74	abiEIP712Domain := []byte("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
 75	hashEIP712Domain := sha3.NewLegacyKeccak256()
 76	hashEIP712Domain.Write(abiEIP712Domain)
 77	var encodeBytes []byte
 78	paddedHash := ethCommon.LeftPadBytes(hashEIP712Domain.Sum(nil), 32)
 79	hashName := sha3.NewLegacyKeccak256()
 80	hashName.Write([]byte(tokenName))
 81	paddedName := ethCommon.LeftPadBytes(hashName.Sum(nil), 32)
 82	hashVersion := sha3.NewLegacyKeccak256()
 83	hashVersion.Write([]byte("1"))
 84	paddedX := ethCommon.LeftPadBytes(hashVersion.Sum(nil), 32)
 85	paddedChainID := ethCommon.LeftPadBytes(chainID.Bytes(), 32)
 86	paddedAddr := ethCommon.LeftPadBytes(tokenAddr.Bytes(), 32)
 87	encodeBytes = append(encodeBytes, paddedHash...)
 88	encodeBytes = append(encodeBytes, paddedName...)
 89	encodeBytes = append(encodeBytes, paddedX...)
 90	encodeBytes = append(encodeBytes, paddedChainID...)
 91	encodeBytes = append(encodeBytes, paddedAddr...)
 92	_domainSeparator := sha3.NewLegacyKeccak256()
 93	_domainSeparator.Write(encodeBytes)
 94
 95	var bytes1 []byte
 96	paddedHashPermit := ethCommon.LeftPadBytes(hashPermit.Sum(nil), 32)
 97	paddedOwner := ethCommon.LeftPadBytes(owner.Bytes(), 32)
 98	paddedSpender := ethCommon.LeftPadBytes(spender.Bytes(), 32)
 99	paddedValue := ethCommon.LeftPadBytes(value.Bytes(), 32)
100	paddedNonce := ethCommon.LeftPadBytes(nonce.Bytes(), 32)
101	paddedDeadline := ethCommon.LeftPadBytes(deadline.Bytes(), 32)
102	bytes1 = append(bytes1, paddedHashPermit...)
103	bytes1 = append(bytes1, paddedOwner...)
104	bytes1 = append(bytes1, paddedSpender...)
105	bytes1 = append(bytes1, paddedValue...)
106	bytes1 = append(bytes1, paddedNonce...)
107	bytes1 = append(bytes1, paddedDeadline...)
108	hashBytes1 := sha3.NewLegacyKeccak256()
109	hashBytes1.Write(bytes1)
110
111	var bytes2 []byte
112	byte19, err := hex.DecodeString("19")
113	if err != nil {
114		return nil, err
115	}
116	byte01, err := hex.DecodeString("01")
117	if err != nil {
118		return nil, err
119	}
120	paddedY := ethCommon.LeftPadBytes(byte19, 1)
121	paddedZ := ethCommon.LeftPadBytes(byte01, 1)
122	paddedDomainSeparator := ethCommon.LeftPadBytes(_domainSeparator.Sum(nil), 32)
123	paddedHashBytes1 := ethCommon.LeftPadBytes(hashBytes1.Sum(nil), 32)
124	bytes2 = append(bytes2, paddedY...)
125	bytes2 = append(bytes2, paddedZ...)
126	bytes2 = append(bytes2, paddedDomainSeparator...)
127	bytes2 = append(bytes2, paddedHashBytes1...)
128	hashBytes2 := sha3.NewLegacyKeccak256()
129	hashBytes2.Write(bytes2)
130
131	return hashBytes2.Sum(nil), nil
132}
133
134func createPermit(owner, spender ethCommon.Address, amount, deadline *big.Int, digest, signature []byte) []byte {
135	r := signature[0:32]
136	s := signature[32:64]
137	v := signature[64] + byte(27)
138
139	ABIpermit := []byte("permit(address,address,uint256,uint256,uint8,bytes32,bytes32)")
140	hash := sha3.NewLegacyKeccak256()
141	hash.Write(ABIpermit)
142	methodID := hash.Sum(nil)[:4]
143
144	var permit []byte
145	paddedOwner := ethCommon.LeftPadBytes(owner.Bytes(), 32)
146	paddedSpender := ethCommon.LeftPadBytes(spender.Bytes(), 32)
147	paddedAmount := ethCommon.LeftPadBytes(amount.Bytes(), 32)
148	paddedDeadline := ethCommon.LeftPadBytes(deadline.Bytes(), 32)
149	paddedV := ethCommon.LeftPadBytes([]byte{v}, 32)
150
151	permit = append(permit, methodID...)
152	permit = append(permit, paddedOwner...)
153	permit = append(permit, paddedSpender...)
154	permit = append(permit, paddedAmount...)
155	permit = append(permit, paddedDeadline...)
156	permit = append(permit, paddedV...)
157	permit = append(permit, r...)
158	permit = append(permit, s...)
159
160	return permit
161}