ethers
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A complete and compact Ethereum library, for dapps, wallets and any other tools.
519 lines • 19.7 kB
JavaScript
//import { TypedDataDomain, TypedDataField } from "@ethersproject/providerabstract-signer";
import { getAddress } from "../address/index.js";
import { keccak256 } from "../crypto/index.js";
import { recoverAddress } from "../transaction/index.js";
import { concat, defineProperties, getBigInt, getBytes, hexlify, isHexString, mask, toBeHex, toQuantity, toTwos, zeroPadValue, assertArgument } from "../utils/index.js";
import { id } from "./id.js";
const padding = new Uint8Array(32);
padding.fill(0);
const BN__1 = BigInt(-1);
const BN_0 = BigInt(0);
const BN_1 = BigInt(1);
const BN_MAX_UINT256 = BigInt("0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
;
;
function hexPadRight(value) {
const bytes = getBytes(value);
const padOffset = bytes.length % 32;
if (padOffset) {
return concat([bytes, padding.slice(padOffset)]);
}
return hexlify(bytes);
}
const hexTrue = toBeHex(BN_1, 32);
const hexFalse = toBeHex(BN_0, 32);
const domainFieldTypes = {
name: "string",
version: "string",
chainId: "uint256",
verifyingContract: "address",
salt: "bytes32"
};
const domainFieldNames = [
"name", "version", "chainId", "verifyingContract", "salt"
];
function checkString(key) {
return function (value) {
assertArgument(typeof (value) === "string", `invalid domain value for ${JSON.stringify(key)}`, `domain.${key}`, value);
return value;
};
}
const domainChecks = {
name: checkString("name"),
version: checkString("version"),
chainId: function (_value) {
const value = getBigInt(_value, "domain.chainId");
assertArgument(value >= 0, "invalid chain ID", "domain.chainId", _value);
if (Number.isSafeInteger(value)) {
return Number(value);
}
return toQuantity(value);
},
verifyingContract: function (value) {
try {
return getAddress(value).toLowerCase();
}
catch (error) { }
assertArgument(false, `invalid domain value "verifyingContract"`, "domain.verifyingContract", value);
},
salt: function (value) {
const bytes = getBytes(value, "domain.salt");
assertArgument(bytes.length === 32, `invalid domain value "salt"`, "domain.salt", value);
return hexlify(bytes);
}
};
function getBaseEncoder(type) {
// intXX and uintXX
{
const match = type.match(/^(u?)int(\d+)$/);
if (match) {
const signed = (match[1] === "");
const width = parseInt(match[2]);
assertArgument(width % 8 === 0 && width !== 0 && width <= 256 && match[2] === String(width), "invalid numeric width", "type", type);
const boundsUpper = mask(BN_MAX_UINT256, signed ? (width - 1) : width);
const boundsLower = signed ? ((boundsUpper + BN_1) * BN__1) : BN_0;
return function (_value) {
const value = getBigInt(_value, "value");
assertArgument(value >= boundsLower && value <= boundsUpper, `value out-of-bounds for ${type}`, "value", value);
return toBeHex(signed ? toTwos(value, 256) : value, 32);
};
}
}
// bytesXX
{
const match = type.match(/^bytes(\d+)$/);
if (match) {
const width = parseInt(match[1]);
assertArgument(width !== 0 && width <= 32 && match[1] === String(width), "invalid bytes width", "type", type);
return function (value) {
const bytes = getBytes(value);
assertArgument(bytes.length === width, `invalid length for ${type}`, "value", value);
return hexPadRight(value);
};
}
}
switch (type) {
case "address": return function (value) {
return zeroPadValue(getAddress(value), 32);
};
case "bool": return function (value) {
return ((!value) ? hexFalse : hexTrue);
};
case "bytes": return function (value) {
return keccak256(value);
};
case "string": return function (value) {
return id(value);
};
}
return null;
}
function encodeType(name, fields) {
return `${name}(${fields.map(({ name, type }) => (type + " " + name)).join(",")})`;
}
// foo[][3] => { base: "foo", index: "[][3]", array: {
// base: "foo", prefix: "foo[]", count: 3 } }
function splitArray(type) {
const match = type.match(/^([^\x5b]*)((\x5b\d*\x5d)*)(\x5b(\d*)\x5d)$/);
if (match) {
return {
base: match[1],
index: (match[2] + match[4]),
array: {
base: match[1],
prefix: (match[1] + match[2]),
count: (match[5] ? parseInt(match[5]) : -1),
}
};
}
return { base: type };
}
/**
* A **TypedDataEncode** prepares and encodes [[link-eip-712]] payloads
* for signed typed data.
*
* This is useful for those that wish to compute various components of a
* typed data hash, primary types, or sub-components, but generally the
* higher level [[Signer-signTypedData]] is more useful.
*/
export class TypedDataEncoder {
/**
* The primary type for the structured [[types]].
*
* This is derived automatically from the [[types]], since no
* recursion is possible, once the DAG for the types is consturcted
* internally, the primary type must be the only remaining type with
* no parent nodes.
*/
primaryType;
#types;
/**
* The types.
*/
get types() {
return JSON.parse(this.#types);
}
#fullTypes;
#encoderCache;
/**
* Create a new **TypedDataEncoder** for %%types%%.
*
* This performs all necessary checking that types are valid and
* do not violate the [[link-eip-712]] structural constraints as
* well as computes the [[primaryType]].
*/
constructor(_types) {
this.#fullTypes = new Map();
this.#encoderCache = new Map();
// Link struct types to their direct child structs
const links = new Map();
// Link structs to structs which contain them as a child
const parents = new Map();
// Link all subtypes within a given struct
const subtypes = new Map();
const types = {};
Object.keys(_types).forEach((type) => {
types[type] = _types[type].map(({ name, type }) => {
// Normalize the base type (unless name conflict)
let { base, index } = splitArray(type);
if (base === "int" && !_types["int"]) {
base = "int256";
}
if (base === "uint" && !_types["uint"]) {
base = "uint256";
}
return { name, type: (base + (index || "")) };
});
links.set(type, new Set());
parents.set(type, []);
subtypes.set(type, new Set());
});
this.#types = JSON.stringify(types);
for (const name in types) {
const uniqueNames = new Set();
for (const field of types[name]) {
// Check each field has a unique name
assertArgument(!uniqueNames.has(field.name), `duplicate variable name ${JSON.stringify(field.name)} in ${JSON.stringify(name)}`, "types", _types);
uniqueNames.add(field.name);
// Get the base type (drop any array specifiers)
const baseType = splitArray(field.type).base;
assertArgument(baseType !== name, `circular type reference to ${JSON.stringify(baseType)}`, "types", _types);
// Is this a base encoding type?
const encoder = getBaseEncoder(baseType);
if (encoder) {
continue;
}
assertArgument(parents.has(baseType), `unknown type ${JSON.stringify(baseType)}`, "types", _types);
// Add linkage
parents.get(baseType).push(name);
links.get(name).add(baseType);
}
}
// Deduce the primary type
const primaryTypes = Array.from(parents.keys()).filter((n) => (parents.get(n).length === 0));
assertArgument(primaryTypes.length !== 0, "missing primary type", "types", _types);
assertArgument(primaryTypes.length === 1, `ambiguous primary types or unused types: ${primaryTypes.map((t) => (JSON.stringify(t))).join(", ")}`, "types", _types);
defineProperties(this, { primaryType: primaryTypes[0] });
// Check for circular type references
function checkCircular(type, found) {
assertArgument(!found.has(type), `circular type reference to ${JSON.stringify(type)}`, "types", _types);
found.add(type);
for (const child of links.get(type)) {
if (!parents.has(child)) {
continue;
}
// Recursively check children
checkCircular(child, found);
// Mark all ancestors as having this decendant
for (const subtype of found) {
subtypes.get(subtype).add(child);
}
}
found.delete(type);
}
checkCircular(this.primaryType, new Set());
// Compute each fully describe type
for (const [name, set] of subtypes) {
const st = Array.from(set);
st.sort();
this.#fullTypes.set(name, encodeType(name, types[name]) + st.map((t) => encodeType(t, types[t])).join(""));
}
}
/**
* Returnthe encoder for the specific %%type%%.
*/
getEncoder(type) {
let encoder = this.#encoderCache.get(type);
if (!encoder) {
encoder = this.#getEncoder(type);
this.#encoderCache.set(type, encoder);
}
return encoder;
}
#getEncoder(type) {
// Basic encoder type (address, bool, uint256, etc)
{
const encoder = getBaseEncoder(type);
if (encoder) {
return encoder;
}
}
// Array
const array = splitArray(type).array;
if (array) {
const subtype = array.prefix;
const subEncoder = this.getEncoder(subtype);
return (value) => {
assertArgument(array.count === -1 || array.count === value.length, `array length mismatch; expected length ${array.count}`, "value", value);
let result = value.map(subEncoder);
if (this.#fullTypes.has(subtype)) {
result = result.map(keccak256);
}
return keccak256(concat(result));
};
}
// Struct
const fields = this.types[type];
if (fields) {
const encodedType = id(this.#fullTypes.get(type));
return (value) => {
const values = fields.map(({ name, type }) => {
const result = this.getEncoder(type)(value[name]);
if (this.#fullTypes.has(type)) {
return keccak256(result);
}
return result;
});
values.unshift(encodedType);
return concat(values);
};
}
assertArgument(false, `unknown type: ${type}`, "type", type);
}
/**
* Return the full type for %%name%%.
*/
encodeType(name) {
const result = this.#fullTypes.get(name);
assertArgument(result, `unknown type: ${JSON.stringify(name)}`, "name", name);
return result;
}
/**
* Return the encoded %%value%% for the %%type%%.
*/
encodeData(type, value) {
return this.getEncoder(type)(value);
}
/**
* Returns the hash of %%value%% for the type of %%name%%.
*/
hashStruct(name, value) {
return keccak256(this.encodeData(name, value));
}
/**
* Return the fulled encoded %%value%% for the [[types]].
*/
encode(value) {
return this.encodeData(this.primaryType, value);
}
/**
* Return the hash of the fully encoded %%value%% for the [[types]].
*/
hash(value) {
return this.hashStruct(this.primaryType, value);
}
/**
* @_ignore:
*/
_visit(type, value, callback) {
// Basic encoder type (address, bool, uint256, etc)
{
const encoder = getBaseEncoder(type);
if (encoder) {
return callback(type, value);
}
}
// Array
const array = splitArray(type).array;
if (array) {
assertArgument(array.count === -1 || array.count === value.length, `array length mismatch; expected length ${array.count}`, "value", value);
return value.map((v) => this._visit(array.prefix, v, callback));
}
// Struct
const fields = this.types[type];
if (fields) {
return fields.reduce((accum, { name, type }) => {
accum[name] = this._visit(type, value[name], callback);
return accum;
}, {});
}
assertArgument(false, `unknown type: ${type}`, "type", type);
}
/**
* Call %%calback%% for each value in %%value%%, passing the type and
* component within %%value%%.
*
* This is useful for replacing addresses or other transformation that
* may be desired on each component, based on its type.
*/
visit(value, callback) {
return this._visit(this.primaryType, value, callback);
}
/**
* Create a new **TypedDataEncoder** for %%types%%.
*/
static from(types) {
return new TypedDataEncoder(types);
}
/**
* Return the primary type for %%types%%.
*/
static getPrimaryType(types) {
return TypedDataEncoder.from(types).primaryType;
}
/**
* Return the hashed struct for %%value%% using %%types%% and %%name%%.
*/
static hashStruct(name, types, value) {
return TypedDataEncoder.from(types).hashStruct(name, value);
}
/**
* Return the domain hash for %%domain%%.
*/
static hashDomain(domain) {
const domainFields = [];
for (const name in domain) {
if (domain[name] == null) {
continue;
}
const type = domainFieldTypes[name];
assertArgument(type, `invalid typed-data domain key: ${JSON.stringify(name)}`, "domain", domain);
domainFields.push({ name, type });
}
domainFields.sort((a, b) => {
return domainFieldNames.indexOf(a.name) - domainFieldNames.indexOf(b.name);
});
return TypedDataEncoder.hashStruct("EIP712Domain", { EIP712Domain: domainFields }, domain);
}
/**
* Return the fully encoded [[link-eip-712]] %%value%% for %%types%% with %%domain%%.
*/
static encode(domain, types, value) {
return concat([
"0x1901",
TypedDataEncoder.hashDomain(domain),
TypedDataEncoder.from(types).hash(value)
]);
}
/**
* Return the hash of the fully encoded [[link-eip-712]] %%value%% for %%types%% with %%domain%%.
*/
static hash(domain, types, value) {
return keccak256(TypedDataEncoder.encode(domain, types, value));
}
// Replaces all address types with ENS names with their looked up address
/**
* Resolves to the value from resolving all addresses in %%value%% for
* %%types%% and the %%domain%%.
*/
static async resolveNames(domain, types, value, resolveName) {
// Make a copy to isolate it from the object passed in
domain = Object.assign({}, domain);
// Allow passing null to ignore value
for (const key in domain) {
if (domain[key] == null) {
delete domain[key];
}
}
// Look up all ENS names
const ensCache = {};
// Do we need to look up the domain's verifyingContract?
if (domain.verifyingContract && !isHexString(domain.verifyingContract, 20)) {
ensCache[domain.verifyingContract] = "0x";
}
// We are going to use the encoder to visit all the base values
const encoder = TypedDataEncoder.from(types);
// Get a list of all the addresses
encoder.visit(value, (type, value) => {
if (type === "address" && !isHexString(value, 20)) {
ensCache[value] = "0x";
}
return value;
});
// Lookup each name
for (const name in ensCache) {
ensCache[name] = await resolveName(name);
}
// Replace the domain verifyingContract if needed
if (domain.verifyingContract && ensCache[domain.verifyingContract]) {
domain.verifyingContract = ensCache[domain.verifyingContract];
}
// Replace all ENS names with their address
value = encoder.visit(value, (type, value) => {
if (type === "address" && ensCache[value]) {
return ensCache[value];
}
return value;
});
return { domain, value };
}
/**
* Returns the JSON-encoded payload expected by nodes which implement
* the JSON-RPC [[link-eip-712]] method.
*/
static getPayload(domain, types, value) {
// Validate the domain fields
TypedDataEncoder.hashDomain(domain);
// Derive the EIP712Domain Struct reference type
const domainValues = {};
const domainTypes = [];
domainFieldNames.forEach((name) => {
const value = domain[name];
if (value == null) {
return;
}
domainValues[name] = domainChecks[name](value);
domainTypes.push({ name, type: domainFieldTypes[name] });
});
const encoder = TypedDataEncoder.from(types);
// Get the normalized types
types = encoder.types;
const typesWithDomain = Object.assign({}, types);
assertArgument(typesWithDomain.EIP712Domain == null, "types must not contain EIP712Domain type", "types.EIP712Domain", types);
typesWithDomain.EIP712Domain = domainTypes;
// Validate the data structures and types
encoder.encode(value);
return {
types: typesWithDomain,
domain: domainValues,
primaryType: encoder.primaryType,
message: encoder.visit(value, (type, value) => {
// bytes
if (type.match(/^bytes(\d*)/)) {
return hexlify(getBytes(value));
}
// uint or int
if (type.match(/^u?int/)) {
return getBigInt(value).toString();
}
switch (type) {
case "address":
return value.toLowerCase();
case "bool":
return !!value;
case "string":
assertArgument(typeof (value) === "string", "invalid string", "value", value);
return value;
}
assertArgument(false, "unsupported type", "type", type);
})
};
}
}
/**
* Compute the address used to sign the typed data for the %%signature%%.
*/
export function verifyTypedData(domain, types, value, signature) {
return recoverAddress(TypedDataEncoder.hash(domain, types, value), signature);
}
//# sourceMappingURL=typed-data.js.map