1086 lines
41 KiB
JavaScript
1086 lines
41 KiB
JavaScript
"use strict";
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var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
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function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
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return new (P || (P = Promise))(function (resolve, reject) {
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function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
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function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
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function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
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step((generator = generator.apply(thisArg, _arguments || [])).next());
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});
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};
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// @TODO:
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// - warn return/revert non-empty, comment ; !assert(+1 @extra)
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// - In JS add config (positionIndependent)
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// - When checking name collisions, verify no collision in javascript
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import { dirname, resolve } from "path";
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import vm from "vm";
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import { ethers } from "ethers";
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import { Opcode } from "./opcodes";
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import { parse as _parse, parser as _parser } from "./_parser";
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import { version } from "./_version";
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const logger = new ethers.utils.Logger(version);
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const Guard = {};
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function hexConcat(values) {
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return ethers.utils.hexlify(ethers.utils.concat(values.map((v) => {
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if (v instanceof Opcode) {
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return [v.value];
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}
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if (typeof (v) === "number") {
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if (v >= 0 && v <= 255 && !(v % 1)) {
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return ethers.utils.hexlify(v);
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}
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else {
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throw new Error("invalid number: " + v);
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}
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}
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return v;
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})));
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}
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function repeat(char, length) {
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let result = char;
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while (result.length < length) {
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result += result;
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}
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return result.substring(0, length);
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}
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class Script {
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constructor(filename, callback) {
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ethers.utils.defineReadOnly(this, "filename", filename);
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ethers.utils.defineReadOnly(this, "contextObject", this._baseContext(callback));
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ethers.utils.defineReadOnly(this, "context", vm.createContext(this.contextObject));
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}
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_baseContext(callback) {
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return new Proxy({
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__filename: this.filename,
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__dirname: dirname(this.filename),
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console: console,
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Uint8Array: Uint8Array,
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ethers: ethers,
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utils: ethers.utils,
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BigNumber: ethers.BigNumber,
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arrayify: ethers.utils.arrayify,
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concat: hexConcat,
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hexlify: ethers.utils.hexlify,
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zeroPad: function (value, length) {
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return ethers.utils.hexlify(ethers.utils.zeroPad(value, length));
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},
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id: ethers.utils.id,
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keccak256: ethers.utils.keccak256,
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namehash: ethers.utils.namehash,
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sha256: ethers.utils.sha256,
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parseEther: ethers.utils.parseEther,
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formatEther: ethers.utils.formatEther,
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parseUnits: ethers.utils.parseUnits,
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formatUnits: ethers.utils.formatUnits,
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randomBytes: function (length) {
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return ethers.utils.hexlify(ethers.utils.randomBytes(length));
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},
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toUtf8Bytes: ethers.utils.toUtf8Bytes,
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toUtf8String: ethers.utils.toUtf8String,
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formatBytes32String: ethers.utils.formatBytes32String,
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parseBytes32String: ethers.utils.parseBytes32String,
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Opcode: Opcode,
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sighash: function (signature) {
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return ethers.utils.id(ethers.utils.FunctionFragment.from(signature).format()).substring(0, 10);
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},
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topichash: function (signature) {
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return ethers.utils.id(ethers.utils.EventFragment.from(signature).format());
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},
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assemble: assemble,
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disassemble: disassemble,
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Error: Error
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}, {
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get: (obj, key) => {
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if (obj[key]) {
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return obj[key];
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}
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if (!callback) {
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return undefined;
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}
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return callback(key, this._context.context);
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}
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});
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}
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evaluate(code, context) {
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return __awaiter(this, void 0, void 0, function* () {
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if (this._context) {
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throw new Error("evaluation collision");
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}
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this._context = { context: context };
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const script = new vm.Script(code, { filename: this.filename });
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let result = script.runInContext(this.context);
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if (result instanceof Promise) {
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result = yield result;
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}
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this._context = null;
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return result;
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});
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}
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}
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let nextTag = 1;
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function throwError(message, location) {
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return logger.throwError(message, "ASSEMBLER", {
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location: location
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});
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}
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export class Node {
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constructor(guard, location, options) {
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if (guard !== Guard) {
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throwError("cannot instantiate class", location);
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}
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logger.checkAbstract(new.target, Node);
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ethers.utils.defineReadOnly(this, "location", Object.freeze(location));
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ethers.utils.defineReadOnly(this, "tag", `node-${nextTag++}-${this.constructor.name}`);
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for (const key in options) {
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ethers.utils.defineReadOnly(this, key, options[key]);
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}
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}
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// Note: EVERY node must call assemble with `this`, even if only with
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// the bytes "0x" to trigger the offset and bytecode checks
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assemble(assembler, visit) {
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return __awaiter(this, void 0, void 0, function* () {
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assembler.start(this);
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visit(this, "0x");
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assembler.end(this);
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});
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}
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children() {
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return [];
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}
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visit(visit) {
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visit(this);
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this.children().forEach((child) => {
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child.visit(visit);
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});
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}
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static from(options) {
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const Factories = {
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data: DataNode,
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decimal: LiteralNode,
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eval: EvaluationNode,
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exec: ExecutionNode,
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hex: LiteralNode,
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label: LabelNode,
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length: LinkNode,
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offset: LinkNode,
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opcode: OpcodeNode,
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pop: PopNode,
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scope: ScopeNode,
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};
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const factory = Factories[options.type];
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if (!factory) {
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throwError("unknown type: " + options.type, options.loc);
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}
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return factory.from(options);
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}
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}
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export class ValueNode extends Node {
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constructor(guard, location, options) {
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logger.checkAbstract(new.target, ValueNode);
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super(guard, location, options);
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}
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getPushLiteral(value) {
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// Convert value into a hexstring
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const hex = ethers.utils.hexlify(value);
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if (hex === "0x") {
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throwError("invalid literal: 0x", this.location);
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}
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// Make sure it will fit into a push
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const length = ethers.utils.hexDataLength(hex);
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if (length === 0 || length > 32) {
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throwError(`literal out of range: ${hex}`, this.location);
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}
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return hexConcat([Opcode.from("PUSH" + String(length)), hex]);
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}
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}
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export class LiteralNode extends ValueNode {
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constructor(guard, location, value, verbatim) {
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super(guard, location, { value, verbatim });
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}
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assemble(assembler, visit) {
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return __awaiter(this, void 0, void 0, function* () {
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assembler.start(this);
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if (this.verbatim) {
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if (this.value.substring(0, 2) === "0x") {
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visit(this, this.value);
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}
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else {
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visit(this, ethers.BigNumber.from(this.value).toHexString());
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}
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}
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else {
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visit(this, this.getPushLiteral(ethers.BigNumber.from(this.value)));
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}
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assembler.end(this);
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});
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}
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static from(options) {
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if (options.type !== "hex" && options.type !== "decimal") {
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throwError("expected hex or decimal type", options.loc);
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}
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return new LiteralNode(Guard, options.loc, options.value, !!options.verbatim);
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}
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}
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export class PopNode extends ValueNode {
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constructor(guard, location, index) {
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super(guard, location, { index });
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}
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get placeholder() {
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if (this.index === 0) {
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return "$$";
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}
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return "$" + String(this.index);
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}
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static from(options) {
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return new PopNode(Guard, options.loc, options.index);
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}
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}
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export class LinkNode extends ValueNode {
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constructor(guard, location, type, label) {
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super(guard, location, { type, label });
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}
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assemble(assembler, visit) {
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return __awaiter(this, void 0, void 0, function* () {
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assembler.start(this);
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let value = null;
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let isOffset = false;
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const target = assembler.getTarget(this.label);
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if (target instanceof LabelNode) {
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if (this.type === "offset") {
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value = (assembler.getLinkValue(target, this));
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isOffset = true;
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}
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}
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else {
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const result = (assembler.getLinkValue(target, this));
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if (this.type === "offset") {
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value = result.offset;
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isOffset = true;
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}
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else if (this.type === "length") {
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value = result.length;
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}
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}
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if (value == null) {
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throwError("labels can only be targetted as offsets", this.location);
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}
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if (isOffset && assembler.positionIndependentCode) {
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const here = assembler.getOffset(this, this);
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const opcodes = [];
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if (here > value) {
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// Jump backwards
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// Find a literal with length the encodes its own length in the delta
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let literal = "0x";
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for (let w = 1; w <= 5; w++) {
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if (w > 4) {
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throwError("jump too large!", this.location);
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}
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literal = this.getPushLiteral(here - value + w);
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if (ethers.utils.hexDataLength(literal) <= w) {
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literal = ethers.utils.hexZeroPad(literal, w);
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break;
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}
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}
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opcodes.push(literal);
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opcodes.push(Opcode.from("PC"));
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opcodes.push(Opcode.from("SUB"));
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// This also works, in case the above literal thing doesn't work out...
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//opcodes.push(Opcode.from("PC"));
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//opcodes.push(pushLiteral(-delta));
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//opcodes.push(Opcode.from("SWAP1"));
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//opcodes.push(Opcode.from("SUB"));
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}
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else {
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// Jump forwards; this is easy to calculate since we can
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// do PC firat.
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opcodes.push(Opcode.from("PC"));
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opcodes.push(this.getPushLiteral(value - here));
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opcodes.push(Opcode.from("ADD"));
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}
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visit(this, hexConcat(opcodes));
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}
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else {
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visit(this, this.getPushLiteral(value));
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}
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assembler.end(this);
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});
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}
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static from(options) {
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// @TODO: Verify type is offset or link...
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return new LinkNode(Guard, options.loc, options.type, options.label);
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}
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}
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export class OpcodeNode extends ValueNode {
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constructor(guard, location, opcode, operands, instructional) {
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super(guard, location, { instructional, opcode, operands });
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}
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assemble(assembler, visit) {
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return __awaiter(this, void 0, void 0, function* () {
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assembler.start(this);
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// Compute the bytecode in reverse stack order
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for (let i = this.operands.length - 1; i >= 0; i--) {
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yield this.operands[i].assemble(assembler, visit);
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}
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// Append this opcode
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visit(this, ethers.utils.hexlify(this.opcode.value));
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assembler.end(this);
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});
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}
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children() {
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return this.operands;
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}
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visit(visit) {
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for (let i = this.operands.length - 1; i >= 0; i--) {
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this.operands[i].visit(visit);
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}
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visit(this);
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}
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static from(options) {
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if (options.type !== "opcode") {
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throwError("expected opcode type", options.loc);
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}
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const opcode = Opcode.from(options.mnemonic);
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if (!opcode) {
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throwError("unknown opcode: " + options.mnemonic, options.loc);
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}
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const operands = Object.freeze(options.operands.map((o) => {
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const operand = Node.from(o);
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if (!(operand instanceof ValueNode)) {
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throwError("bad grammar?!", options.loc);
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}
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return operand;
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}));
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return new OpcodeNode(Guard, options.loc, opcode, operands, !!options.bare);
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}
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}
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export class LabelledNode extends Node {
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constructor(guard, location, name, values) {
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logger.checkAbstract(new.target, LabelledNode);
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values = ethers.utils.shallowCopy(values || {});
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values.name = name;
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super(guard, location, values);
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}
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}
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export class LabelNode extends LabelledNode {
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assemble(assembler, visit) {
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return __awaiter(this, void 0, void 0, function* () {
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assembler.start(this);
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visit(this, ethers.utils.hexlify(Opcode.from("JUMPDEST").value));
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assembler.end(this);
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});
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}
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static from(options) {
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if (options.type !== "label") {
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throwError("expected label type", options.loc);
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}
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return new LabelNode(Guard, options.loc, options.name);
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}
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}
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export class PaddingNode extends ValueNode {
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constructor(guard, location) {
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super(guard, location, {});
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this._length = 0;
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}
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setLength(length) {
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this._length = length;
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}
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assemble(assembler, visit) {
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return __awaiter(this, void 0, void 0, function* () {
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assembler.start(this);
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const padding = new Uint8Array(this._length);
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padding.fill(0);
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visit(this, ethers.utils.hexlify(padding));
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assembler.end(this);
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});
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}
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}
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export class DataNode extends LabelledNode {
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constructor(guard, location, name, data) {
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super(guard, location, name, { data });
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ethers.utils.defineReadOnly(this, "padding", new PaddingNode(Guard, this.location));
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}
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assemble(assembler, visit) {
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return __awaiter(this, void 0, void 0, function* () {
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assembler.start(this);
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// @TODO: This is a problem... We need to visit before visiting children
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// so offsets are correct, but then we cannot pad...
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visit(this, "0x");
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for (let i = 0; i < this.data.length; i++) {
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yield this.data[i].assemble(assembler, visit);
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}
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// We pad data if is contains PUSH opcodes that would overrun
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// the data, which could eclipse valid operations (since the
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// VM won't execute or jump within PUSH operations)
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const bytecode = ethers.utils.concat(this.data.map((d) => assembler.getBytecode(d)));
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// Replay the data as bytecode, skipping PUSH data
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let i = 0;
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while (i < bytecode.length) {
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const opcode = Opcode.from(bytecode[i++]);
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if (opcode) {
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i += opcode.isPush();
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}
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}
|
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// The amount we overshot the data by is how much padding we need
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this.padding.setLength(i - bytecode.length);
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yield this.padding.assemble(assembler, visit);
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|
assembler.end(this);
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|
});
|
|
}
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children() {
|
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const children = this.data.slice();
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|
children.push(this.padding);
|
|
return children;
|
|
}
|
|
static from(options) {
|
|
if (options.type !== "data") {
|
|
throwError("expected data type", options.loc);
|
|
}
|
|
return new DataNode(Guard, options.loc, options.name, Object.freeze(options.data.map((d) => Node.from(d))));
|
|
}
|
|
}
|
|
export class EvaluationNode extends ValueNode {
|
|
constructor(guard, location, script, verbatim) {
|
|
super(guard, location, { script, verbatim });
|
|
}
|
|
assemble(assembler, visit) {
|
|
return __awaiter(this, void 0, void 0, function* () {
|
|
assembler.start(this);
|
|
const result = yield assembler.evaluate(this.script, this);
|
|
if (this.verbatim) {
|
|
if (typeof (result) === "number") {
|
|
visit(this, ethers.BigNumber.from(result).toHexString());
|
|
}
|
|
else {
|
|
visit(this, ethers.utils.hexlify(result));
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|
}
|
|
}
|
|
else {
|
|
visit(this, this.getPushLiteral(result));
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|
}
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|
assembler.end(this);
|
|
});
|
|
}
|
|
static from(options) {
|
|
if (options.type !== "eval") {
|
|
throwError("expected eval type", options.loc);
|
|
}
|
|
return new EvaluationNode(Guard, options.loc, options.script, !!options.verbatim);
|
|
}
|
|
}
|
|
export class ExecutionNode extends Node {
|
|
constructor(guard, location, script) {
|
|
super(guard, location, { script });
|
|
}
|
|
assemble(assembler, visit) {
|
|
return __awaiter(this, void 0, void 0, function* () {
|
|
assembler.start(this);
|
|
yield assembler.evaluate(this.script, this);
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|
assembler.end(this);
|
|
});
|
|
}
|
|
static from(options) {
|
|
if (options.type !== "exec") {
|
|
throwError("expected exec type", options.loc);
|
|
}
|
|
return new ExecutionNode(Guard, options.loc, options.script);
|
|
}
|
|
}
|
|
export class ScopeNode extends LabelledNode {
|
|
constructor(guard, location, name, statements) {
|
|
super(guard, location, name, { statements });
|
|
}
|
|
assemble(assembler, visit) {
|
|
return __awaiter(this, void 0, void 0, function* () {
|
|
assembler.start(this);
|
|
visit(this, "0x");
|
|
for (let i = 0; i < this.statements.length; i++) {
|
|
yield this.statements[i].assemble(assembler, visit);
|
|
}
|
|
assembler.end(this);
|
|
});
|
|
}
|
|
children() {
|
|
return this.statements;
|
|
}
|
|
static from(options) {
|
|
if (options.type !== "scope") {
|
|
throwError("expected scope type", options.loc);
|
|
}
|
|
return new ScopeNode(Guard, options.loc, options.name, Object.freeze(options.statements.map((s) => Node.from(s))));
|
|
}
|
|
}
|
|
export function disassemble(bytecode) {
|
|
const ops = [];
|
|
const offsets = {};
|
|
const bytes = ethers.utils.arrayify(bytecode, { allowMissingPrefix: true });
|
|
let i = 0;
|
|
let oob = false;
|
|
while (i < bytes.length) {
|
|
let opcode = Opcode.from(bytes[i]);
|
|
if (!opcode) {
|
|
opcode = new Opcode(`unknown (${ethers.utils.hexlify(bytes[i])})`, bytes[i], 0, 0);
|
|
}
|
|
else if (oob && opcode.mnemonic === "JUMPDEST") {
|
|
opcode = new Opcode(`JUMPDEST (invalid; OOB!!)`, bytes[i], 0, 0);
|
|
}
|
|
const op = {
|
|
opcode: opcode,
|
|
offset: i
|
|
};
|
|
offsets[i] = op;
|
|
ops.push(op);
|
|
i++;
|
|
const push = opcode.isPush();
|
|
if (push) {
|
|
const data = ethers.utils.hexlify(bytes.slice(i, i + push));
|
|
if (ethers.utils.hexDataLength(data) === push) {
|
|
op.pushValue = data;
|
|
i += push;
|
|
}
|
|
else {
|
|
oob = true;
|
|
}
|
|
}
|
|
}
|
|
ops.getOperation = function (offset) {
|
|
return (offsets[offset] || null);
|
|
};
|
|
return ops;
|
|
}
|
|
export function formatBytecode(bytecode) {
|
|
const lines = [];
|
|
bytecode.forEach((op) => {
|
|
const opcode = op.opcode;
|
|
let offset = ethers.utils.hexZeroPad(ethers.utils.hexlify(op.offset), 2);
|
|
if (opcode.isValidJumpDest()) {
|
|
offset += "*";
|
|
}
|
|
else {
|
|
offset += " ";
|
|
}
|
|
let operation = opcode.mnemonic;
|
|
const push = opcode.isPush();
|
|
if (push) {
|
|
if (op.pushValue) {
|
|
operation = op.pushValue + `${repeat(" ", 67 - op.pushValue.length)}; #${push} `;
|
|
}
|
|
else {
|
|
operation += `${repeat(" ", 67 - operation.length)}; OOB!! `;
|
|
}
|
|
}
|
|
lines.push(`${offset.substring(2)}: ${operation}`);
|
|
});
|
|
return lines.join("\n");
|
|
}
|
|
class Assembler {
|
|
constructor(root, positionIndependentCode) {
|
|
ethers.utils.defineReadOnly(this, "root", root);
|
|
ethers.utils.defineReadOnly(this, "positionIndependentCode", !!positionIndependentCode);
|
|
const nodes = {};
|
|
const labels = {};
|
|
const parents = {};
|
|
// Link labels to their target node
|
|
root.visit((node) => {
|
|
nodes[node.tag] = {
|
|
node: node,
|
|
offset: 0x0,
|
|
bytecode: "0x"
|
|
};
|
|
if (node instanceof LabelledNode) {
|
|
// Check for duplicate labels
|
|
if (labels[node.name]) {
|
|
logger.throwError(("duplicate label: " + node.name), ethers.utils.Logger.errors.UNSUPPORTED_OPERATION, {});
|
|
}
|
|
labels[node.name] = node;
|
|
}
|
|
});
|
|
root.visit((node) => {
|
|
// Check all labels exist
|
|
if (node instanceof LinkNode) {
|
|
const target = labels[node.label];
|
|
if (!target) {
|
|
logger.throwError(("missing label: " + node.label), ethers.utils.Logger.errors.UNSUPPORTED_OPERATION, {});
|
|
}
|
|
}
|
|
// Build the parent structure
|
|
node.children().forEach((child) => {
|
|
parents[child.tag] = node;
|
|
});
|
|
});
|
|
ethers.utils.defineReadOnly(this, "labels", Object.freeze(labels));
|
|
ethers.utils.defineReadOnly(this, "nodes", Object.freeze(nodes));
|
|
ethers.utils.defineReadOnly(this, "_parents", Object.freeze(parents));
|
|
}
|
|
// Link operations
|
|
getTarget(label) {
|
|
return this.labels[label];
|
|
}
|
|
// Evaluate script in the context of a {{! }} or {{= }}
|
|
evaluate(script, source) {
|
|
return Promise.resolve(new Uint8Array(0));
|
|
}
|
|
getAncestor(node, cls) {
|
|
node = this._parents[node.tag];
|
|
while (node) {
|
|
if (node instanceof cls) {
|
|
return node;
|
|
}
|
|
node = this._parents[node.tag];
|
|
}
|
|
return null;
|
|
}
|
|
getOffset(node, source) {
|
|
const offset = this.nodes[node.tag].offset;
|
|
if (source == null) {
|
|
return offset;
|
|
}
|
|
const sourceScope = ((source instanceof ScopeNode) ? source : this.getAncestor(source, ScopeNode));
|
|
return offset - this.nodes[sourceScope.tag].offset;
|
|
}
|
|
setOffset(node, offset) {
|
|
this.nodes[node.tag].offset = offset;
|
|
}
|
|
getBytecode(node) {
|
|
return this.nodes[node.tag].bytecode;
|
|
}
|
|
setBytecode(node, bytecode) {
|
|
this.nodes[node.tag].bytecode = bytecode;
|
|
}
|
|
getLinkValue(target, source) {
|
|
const sourceScope = ((source instanceof ScopeNode) ? source : this.getAncestor(source, ScopeNode));
|
|
const targetScope = ((target instanceof ScopeNode) ? target : this.getAncestor(target, ScopeNode));
|
|
if (target instanceof LabelNode) {
|
|
// Label offset (e.g. "@foo:"); accessible only within its direct scope
|
|
//const scope = this.getAncestor(source, Scope);
|
|
if (targetScope !== sourceScope) {
|
|
throwError(`cannot access ${target.name} from ${source.tag}`, source.location);
|
|
}
|
|
// Return the offset relative to its scope
|
|
return this.nodes[target.tag].offset - this.nodes[targetScope.tag].offset;
|
|
}
|
|
const info = this.nodes[target.tag];
|
|
// Return the offset is relative to its scope
|
|
const bytes = Array.prototype.slice.call(ethers.utils.arrayify(info.bytecode));
|
|
ethers.utils.defineReadOnly(bytes, "ast", target);
|
|
ethers.utils.defineReadOnly(bytes, "source", target.location.source);
|
|
if (!((target instanceof DataNode) || (target instanceof ScopeNode))) {
|
|
throwError("invalid link value lookup", source.location);
|
|
}
|
|
// Check that target is any descendant (or self) of the source scope
|
|
let safeOffset = (sourceScope == targetScope);
|
|
if (!safeOffset) {
|
|
sourceScope.visit((node) => {
|
|
if (node === targetScope) {
|
|
safeOffset = true;
|
|
}
|
|
});
|
|
}
|
|
// Not safe to access the offset; this will fault if anything tries.
|
|
if (!safeOffset) {
|
|
Object.defineProperty(bytes, "offset", {
|
|
get: function () { throwError(`cannot access ${target.name}.offset from ${source.tag}`, this.location); }
|
|
});
|
|
ethers.utils.defineReadOnly(bytes, "_freeze", function () { });
|
|
}
|
|
// Add the offset relative to the scope; unless the offset has
|
|
// been marked as invalid, in which case accessing it will fail
|
|
if (safeOffset) {
|
|
bytes.offset = info.offset - this.nodes[sourceScope.tag].offset;
|
|
let frozen = false;
|
|
ethers.utils.defineReadOnly(bytes, "_freeze", function () {
|
|
if (frozen) {
|
|
return;
|
|
}
|
|
frozen = true;
|
|
ethers.utils.defineReadOnly(bytes, "offset", bytes.offset);
|
|
});
|
|
}
|
|
return bytes;
|
|
}
|
|
start(node) { }
|
|
end(node) { }
|
|
}
|
|
export var SemanticErrorSeverity;
|
|
(function (SemanticErrorSeverity) {
|
|
SemanticErrorSeverity["error"] = "error";
|
|
SemanticErrorSeverity["warning"] = "warning";
|
|
})(SemanticErrorSeverity || (SemanticErrorSeverity = {}));
|
|
;
|
|
// This Assembler is designed to only check for errors and warnings
|
|
// Warnings
|
|
// - Bare PUSH opcodes
|
|
// - Instructional opcode that has parameters
|
|
// Errors
|
|
// - Using a $$ outside of RPN
|
|
// - Using a $$ when it is not adjacent to the stack
|
|
// - The operand count does not match the opcode
|
|
// - An opcode is used as an operand but does not return a value
|
|
class SemanticChecker extends Assembler {
|
|
check() {
|
|
const errors = [];
|
|
this.root.visit((node) => {
|
|
if (node instanceof OpcodeNode) {
|
|
const opcode = node.opcode;
|
|
if (node.instructional) {
|
|
if (opcode.delta) {
|
|
errors.push({
|
|
message: `${opcode.mnemonic} used as instructional`,
|
|
severity: SemanticErrorSeverity.warning,
|
|
node: node
|
|
});
|
|
}
|
|
}
|
|
else {
|
|
if (opcode.mnemonic === "POP") {
|
|
if (node.operands.length !== 0) {
|
|
errors.push({
|
|
message: "POP expects 0 operands",
|
|
severity: SemanticErrorSeverity.error,
|
|
node: node
|
|
});
|
|
}
|
|
}
|
|
else if (node.operands.length !== opcode.delta) {
|
|
errors.push({
|
|
message: `${opcode.mnemonic} expects ${opcode.delta} operands`,
|
|
severity: SemanticErrorSeverity.error,
|
|
node: node
|
|
});
|
|
}
|
|
}
|
|
if (opcode.isPush()) {
|
|
// A stray PUSH operation will gobble up the following code
|
|
// bytes which is bad. But this may be a disassembled program
|
|
// and that PUSH may actually be just some data (which is safe)
|
|
errors.push({
|
|
message: "PUSH opcode modifies program flow - use literals instead",
|
|
severity: SemanticErrorSeverity.warning,
|
|
node: node
|
|
});
|
|
}
|
|
else if (!node.location.statement && opcode.alpha !== 1) {
|
|
// If an opcode does not push anything on the stack, it
|
|
// cannot be used as an operand
|
|
errors.push({
|
|
message: `${node.opcode.mnemonic} cannot be an operand`,
|
|
severity: SemanticErrorSeverity.error,
|
|
node: node
|
|
});
|
|
}
|
|
}
|
|
if (node.location.statement) {
|
|
if (node instanceof PopNode) {
|
|
// $$ by istelf is useless and is intended to be an operand
|
|
errors.push({
|
|
message: `$$ must be an operand`,
|
|
severity: SemanticErrorSeverity.error,
|
|
node: node
|
|
});
|
|
}
|
|
else {
|
|
const scope = this.getAncestor(node, ScopeNode);
|
|
// Make sure any $$ is stack adjacent (within this scope)
|
|
const ordered = [];
|
|
node.visit((node) => {
|
|
if (scope !== this.getAncestor(node, ScopeNode)) {
|
|
return;
|
|
}
|
|
ordered.push(node);
|
|
});
|
|
// Allow any number of stack adjacent $$
|
|
let foundZero = null;
|
|
let lastIndex = 0;
|
|
while (ordered.length && ordered[0] instanceof PopNode) {
|
|
const popNode = (ordered.shift());
|
|
const index = popNode.index;
|
|
if (index === 0) {
|
|
foundZero = popNode;
|
|
}
|
|
else if (index !== lastIndex + 1) {
|
|
errors.push({
|
|
message: `out-of-order stack placeholder ${popNode.placeholder}; expected $$${lastIndex + 1}`,
|
|
severity: SemanticErrorSeverity.error,
|
|
node: popNode
|
|
});
|
|
while (ordered.length && ordered[0] instanceof PopNode) {
|
|
ordered.shift();
|
|
}
|
|
break;
|
|
}
|
|
else {
|
|
lastIndex = index;
|
|
}
|
|
}
|
|
if (foundZero && lastIndex > 0) {
|
|
errors.push({
|
|
message: "cannot mix $$ and $1 stack placeholder",
|
|
severity: SemanticErrorSeverity.error,
|
|
node: foundZero
|
|
});
|
|
}
|
|
// If there are still any buried, we have a problem
|
|
const pops = ordered.filter((n) => (n instanceof PopNode));
|
|
if (pops.length) {
|
|
errors.push({
|
|
message: `stack placeholder ${(pops[0]).placeholder} must be stack adjacent`,
|
|
severity: SemanticErrorSeverity.error,
|
|
node: pops[0]
|
|
});
|
|
}
|
|
}
|
|
}
|
|
});
|
|
return errors;
|
|
}
|
|
}
|
|
class CodeGenerationAssembler extends Assembler {
|
|
constructor(root, options) {
|
|
super(root, !!options.positionIndependentCode);
|
|
ethers.utils.defineReadOnly(this, "retry", ((options.retry != null) ? options.retry : 512));
|
|
ethers.utils.defineReadOnly(this, "filename", resolve(options.filename || "./contract.asm"));
|
|
ethers.utils.defineReadOnly(this, "defines", Object.freeze(options.defines || {}));
|
|
ethers.utils.defineReadOnly(this, "_stack", []);
|
|
this.reset();
|
|
}
|
|
_didChange() {
|
|
this._changed = true;
|
|
}
|
|
get changed() {
|
|
return this._changed;
|
|
}
|
|
// Reset the assmebler for another run with updated values
|
|
reset() {
|
|
this._changed = false;
|
|
this._objectCache = {};
|
|
this._nextBytecode = {};
|
|
this._script = new Script(this.filename, (name, context) => {
|
|
return this.get(name, context);
|
|
});
|
|
this._checks = [];
|
|
}
|
|
evaluate(script, source) {
|
|
return this._script.evaluate(script, source);
|
|
}
|
|
_runChecks() {
|
|
this._checks.forEach((func) => {
|
|
if (!func()) {
|
|
this._didChange();
|
|
}
|
|
});
|
|
}
|
|
getLinkValue(target, source) {
|
|
// Since we are iteratively generating code, offsets and lengths
|
|
// may not be stable at any given point in time, so if an offset
|
|
// is negative the code is obviously wrong, however we set it to
|
|
// 0 so we can proceed with generation to fill in as many blanks
|
|
// as possible; then we will try assembling again
|
|
const result = super.getLinkValue(target, source);
|
|
if (typeof (result) === "number") {
|
|
if (result < 0) {
|
|
this._checks.push(() => false);
|
|
return 0;
|
|
}
|
|
this._checks.push(() => {
|
|
return (super.getLinkValue(target, source) === result);
|
|
});
|
|
return result;
|
|
}
|
|
// The offset cannot be used so is independent
|
|
try {
|
|
if (result.offset < 0) {
|
|
this._checks.push(() => false);
|
|
result.offset = 0;
|
|
//this._didChange();
|
|
}
|
|
else {
|
|
this._checks.push(() => {
|
|
const check = super.getLinkValue(target, source);
|
|
if (check.offset === result.offset && ethers.utils.hexlify(check) === ethers.utils.hexlify(result)) {
|
|
return true;
|
|
}
|
|
return false;
|
|
});
|
|
}
|
|
}
|
|
catch (error) {
|
|
this._checks.push(() => {
|
|
const check = super.getLinkValue(target, source);
|
|
return (ethers.utils.hexlify(check) === ethers.utils.hexlify(result));
|
|
});
|
|
}
|
|
return result;
|
|
}
|
|
start(node) {
|
|
this._stack.push(node);
|
|
//this._oldBytecode[node.tag] = this.getBytecode(node);
|
|
//this.setBytecode(node, "0x");
|
|
this._nextBytecode[node.tag] = "0x";
|
|
}
|
|
end(node) {
|
|
if (this._stack.pop() !== node) {
|
|
throwError("missing push/pop pair", node.location);
|
|
}
|
|
const oldBytecode = this.getBytecode(node);
|
|
this.setBytecode(node, this._nextBytecode[node.tag]);
|
|
if (!(node instanceof PaddingNode)) {
|
|
this._checks.push(() => {
|
|
return (oldBytecode === this.getBytecode(node));
|
|
});
|
|
}
|
|
}
|
|
// This is used by evaluate to access properties in JavaScript
|
|
// - "defines" allow meta-programming values to be used
|
|
// - jump destinations are available as numbers
|
|
// - bytecode and data are available as an immuatble DataSource
|
|
get(name, source) {
|
|
if (name === "defines") {
|
|
return this.defines;
|
|
}
|
|
else if (name === "_ok") {
|
|
this._runChecks();
|
|
return !this._didChange;
|
|
}
|
|
const node = this.labels[name];
|
|
if (!node) {
|
|
return undefined;
|
|
}
|
|
// We cache objects when they are generated so all nodes
|
|
// receive consistent data; if there is a change we will
|
|
// run the entire assembly process again with the updated
|
|
// values
|
|
if (this._objectCache[node.tag] == null) {
|
|
const result = this.getLinkValue(node, source);
|
|
if (typeof (result) !== "number") {
|
|
result._freeze();
|
|
}
|
|
this._objectCache[node.tag] = result;
|
|
}
|
|
return this._objectCache[node.tag];
|
|
}
|
|
_assemble() {
|
|
return __awaiter(this, void 0, void 0, function* () {
|
|
let offset = 0;
|
|
yield this.root.assemble(this, (node, bytecode) => {
|
|
// Things have moved; we will need to try again
|
|
if (this.getOffset(node) !== offset) {
|
|
this.setOffset(node, offset);
|
|
//this._didChange();
|
|
this._checks.push(() => false);
|
|
}
|
|
this._stack.forEach((node) => {
|
|
this._nextBytecode[node.tag] = hexConcat([
|
|
this._nextBytecode[node.tag],
|
|
bytecode
|
|
]);
|
|
});
|
|
offset += ethers.utils.hexDataLength(bytecode);
|
|
});
|
|
this._runChecks();
|
|
});
|
|
}
|
|
assemble(label) {
|
|
return __awaiter(this, void 0, void 0, function* () {
|
|
if (label == null) {
|
|
label = "_";
|
|
}
|
|
const target = this.getTarget(label);
|
|
if (!target) {
|
|
logger.throwArgumentError(`unknown labelled target: ${label}`, "label", label);
|
|
}
|
|
else if (!(target instanceof ScopeNode || target instanceof DataNode)) {
|
|
logger.throwArgumentError(`cannot assemble a bodyless label: ${label}`, "label", label);
|
|
}
|
|
// Continue re-evaluating the bytecode until a stable set of
|
|
// offsets, length and values are reached.
|
|
yield this._assemble();
|
|
for (let i = 0; i < this.retry; i++) {
|
|
// Regenerate the code with the updated assembler values
|
|
this.reset();
|
|
yield this._assemble();
|
|
// Generated bytecode is stable!! :)
|
|
if (!this.changed) {
|
|
// This should not happen; something is wrong with the grammar
|
|
// or missing enter/exit call in assemble
|
|
if (this._stack.length !== 0) {
|
|
throwError("Bad AST! Bad grammar?!", null);
|
|
}
|
|
//console.log(`Assembled in ${ i } attempts`);
|
|
return this.getBytecode(target);
|
|
}
|
|
}
|
|
return logger.throwError(`unable to assemble; ${this.retry} attempts failed to generate stable bytecode`, ethers.utils.Logger.errors.UNKNOWN_ERROR, {});
|
|
});
|
|
}
|
|
}
|
|
export function parse(code, options) {
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if (options == null) {
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options = {};
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}
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// Since jison allows \n, \r or \r\n line endings, we need some
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// twekaing to get the correct position
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const lines = [];
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let offset = 0;
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code.split(/(\r\n?|\n)/g).forEach((clump, index) => {
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if (index % 2) {
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lines[lines.length - 1].line += clump;
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}
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else {
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lines.push({ line: clump, offset: offset });
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}
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offset += clump.length;
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});
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// Add a mock-EOF to the end of the file so we don't out-of-bounds
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// on the last character
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if (lines.length) {
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lines[lines.length - 1].line += "\n";
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}
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// Givens a line (1 offset) and column (0 offset) return the byte offset
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const getOffset = function (line, column) {
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const info = lines[line - 1];
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if (!info || column >= info.line.length) {
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throw new Error("out of range");
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}
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return info.offset + column;
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};
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// We use this in the _parser to convert locations to source
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_parser.yy._ethersLocation = function (loc) {
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// The _ scope should call with null to get the full source
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if (loc == null) {
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return {
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offset: 0,
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line: 0,
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length: code.length,
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source: code,
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statement: true
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|
};
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}
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const offset = getOffset(loc.first_line, loc.first_column);
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const end = getOffset(loc.last_line, loc.last_column);
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return {
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offset: offset,
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line: loc.first_line - 1,
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length: (end - offset),
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source: code.substring(offset, end),
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statement: (!!loc.statement)
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};
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};
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const result = Node.from(_parse(code));
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// Nuke the source code lookup callback
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|
_parser.yy._ethersLocation = null;
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// Semantic Checks
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|
const checker = new SemanticChecker(result);
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|
const errors = checker.check();
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|
if (errors.filter((e) => (e.severity === SemanticErrorSeverity.error)).length || (errors.length && !options.ignoreWarnings)) {
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|
const error = new Error("semantic errors during parsing");
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|
error.errors = errors;
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|
throw error;
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|
}
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|
return result;
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|
}
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export function assemble(ast, options) {
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|
return __awaiter(this, void 0, void 0, function* () {
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const assembler = new CodeGenerationAssembler(ast, options || {});
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|
return assembler.assemble(options.target || "_");
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});
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}
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