UNPKG

@iden3/js-jwz

Version:

JS implementation of JWZ

293 lines (292 loc) 10.6 kB
/* eslint-disable require-await */ /* eslint-disable @typescript-eslint/no-explicit-any */ export async function witnessBuilder(code, options) { options = options || {}; let wasmModule; try { wasmModule = await WebAssembly.compile(code); } catch (err) { // eslint-disable-next-line no-console console.log(err); // eslint-disable-next-line no-console console.log('\nTry to run circom --c in order to generate c++ code instead\n'); throw new Error(err); } let errStr = ''; let msgStr = ''; const instance = await WebAssembly.instantiate(wasmModule, { runtime: { exceptionHandler: function (code) { let err; if (code == 1) { err = 'Signal not found.\n'; } else if (code == 2) { err = 'Too many signals set.\n'; } else if (code == 3) { err = 'Signal already set.\n'; } else if (code == 4) { err = 'Assert Failed.\n'; } else if (code == 5) { err = 'Not enough memory.\n'; } else if (code == 6) { err = 'Input signal array access exceeds the size.\n'; } else { err = 'Unknown error.\n'; } throw new Error(err + errStr); }, printErrorMessage: function () { errStr += getMessage() + '\n'; // console.error(getMessage()); }, writeBufferMessage: function () { const msg = getMessage(); // Any calls to `log()` will always end with a `\n`, so that's when we print and reset if (msg === '\n') { // eslint-disable-next-line no-console console.log(msgStr); msgStr = ''; } else { // If we've buffered other content, put a space in between the items if (msgStr !== '') { msgStr += ' '; } // Then append the message to the message we are creating msgStr += msg; } }, showSharedRWMemory: function () { printSharedRWMemory(); } } }); const sanityCheck = options; // options && // ( // options.sanityCheck || // options.logGetSignal || // options.logSetSignal || // options.logStartComponent || // options.logFinishComponent // ); const wc = new WitnessCalculator(instance, sanityCheck); return wc; function getMessage() { let message = ''; let c = instance.exports.getMessageChar(); while (c != 0) { message += String.fromCharCode(c); c = instance.exports.getMessageChar(); } return message; } function printSharedRWMemory() { const shared_rw_memory_size = instance.exports.getFieldNumLen32(); const arr = new Uint32Array(shared_rw_memory_size); for (let j = 0; j < shared_rw_memory_size; j++) { arr[shared_rw_memory_size - 1 - j] = instance.exports.readSharedRWMemory(j); } // If we've buffered other content, put a space in between the items if (msgStr !== '') { msgStr += ' '; } // Then append the value to the message we are creating msgStr += fromArray32(arr).toString(); } } class WitnessCalculator { constructor(instance, sanityCheck) { this.instance = instance; this.instance = instance; this.version = this.instance.exports.getVersion(); this.n32 = this.instance.exports.getFieldNumLen32(); this.instance.exports.getRawPrime(); const arr = new Uint32Array(this.n32); for (let i = 0; i < this.n32; i++) { arr[this.n32 - 1 - i] = this.instance.exports.readSharedRWMemory(i); } this.prime = fromArray32(arr); this.witnessSize = this.instance.exports.getWitnessSize(); this.sanityCheck = sanityCheck; } circom_version() { return this.instance.exports.getVersion(); } async _doCalculateWitness(input, sanityCheck) { //input is assumed to be a map from signals to arrays of bigints this.instance.exports.init(this.sanityCheck || sanityCheck ? 1 : 0); const keys = Object.keys(input); let input_counter = 0; keys.forEach((k) => { const h = fnvHash(k); const hMSB = parseInt(h.slice(0, 8), 16); const hLSB = parseInt(h.slice(8, 16), 16); const fArr = flatArray(input[k]); const signalSize = this.instance.exports.getInputSignalSize(hMSB, hLSB); if (signalSize < 0) { throw new Error(`Signal ${k} not found\n`); } if (fArr.length < signalSize) { throw new Error(`Not enough values for input signal ${k}\n`); } if (fArr.length > signalSize) { throw new Error(`Too many values for input signal ${k}\n`); } for (let i = 0; i < fArr.length; i++) { const arrFr = toArray32(BigInt(fArr[i]) % this.prime, this.n32); for (let j = 0; j < this.n32; j++) { this.instance.exports.writeSharedRWMemory(j, arrFr[this.n32 - 1 - j]); } try { this.instance.exports.setInputSignal(hMSB, hLSB, i); input_counter++; } catch (err) { // console.log(`After adding signal ${i} of ${k}`) throw new Error(err); } } }); if (input_counter < this.instance.exports.getInputSize()) { throw new Error(`Not all inputs have been set. Only ${input_counter} out of ${this.instance.exports.getInputSize()}`); } } async calculateWitness(input, sanityCheck) { const w = []; await this._doCalculateWitness(input, sanityCheck); for (let i = 0; i < this.witnessSize; i++) { this.instance.exports.getWitness(i); const arr = new Uint32Array(this.n32); for (let j = 0; j < this.n32; j++) { arr[this.n32 - 1 - j] = this.instance.exports.readSharedRWMemory(j); } w.push(fromArray32(arr)); } return w; } async calculateBinWitness(input, sanityCheck) { const buff32 = new Uint32Array(this.witnessSize * this.n32); const buff = new Uint8Array(buff32.buffer); await this._doCalculateWitness(input, sanityCheck); for (let i = 0; i < this.witnessSize; i++) { this.instance.exports.getWitness(i); const pos = i * this.n32; for (let j = 0; j < this.n32; j++) { buff32[pos + j] = this.instance.exports.readSharedRWMemory(j); } } return buff; } async calculateWTNSBin(input, sanityCheck) { const buff32 = new Uint32Array(this.witnessSize * this.n32 + this.n32 + 11); const buff = new Uint8Array(buff32.buffer); await this._doCalculateWitness(input, sanityCheck); //"wtns" buff[0] = 'w'.charCodeAt(0); buff[1] = 't'.charCodeAt(0); buff[2] = 'n'.charCodeAt(0); buff[3] = 's'.charCodeAt(0); //version 2 buff32[1] = 2; //number of sections: 2 buff32[2] = 2; //id section 1 buff32[3] = 1; const n8 = this.n32 * 4; //id section 1 length in 64bytes const idSection1length = 8 + n8; const idSection1lengthHex = idSection1length.toString(16); buff32[4] = parseInt(idSection1lengthHex.slice(0, 8), 16); buff32[5] = parseInt(idSection1lengthHex.slice(8, 16), 16); //this.n32 buff32[6] = n8; //prime number this.instance.exports.getRawPrime(); let pos = 7; for (let j = 0; j < this.n32; j++) { buff32[pos + j] = this.instance.exports.readSharedRWMemory(j); } pos += this.n32; // witness size buff32[pos] = this.witnessSize; pos++; //id section 2 buff32[pos] = 2; pos++; // section 2 length const idSection2length = n8 * this.witnessSize; const idSection2lengthHex = idSection2length.toString(16); buff32[pos] = parseInt(idSection2lengthHex.slice(0, 8), 16); buff32[pos + 1] = parseInt(idSection2lengthHex.slice(8, 16), 16); pos += 2; for (let i = 0; i < this.witnessSize; i++) { this.instance.exports.getWitness(i); for (let j = 0; j < this.n32; j++) { buff32[pos + j] = this.instance.exports.readSharedRWMemory(j); } pos += this.n32; } return buff; } } function toArray32(rem, size) { const res = []; //new Uint32Array(size); //has no unshift const radix = BigInt(0x100000000); while (rem) { res.unshift(Number(rem % radix)); rem = rem / radix; } if (size) { let i = size - res.length; while (i > 0) { res.unshift(0); i--; } } return res; } function fromArray32(arr) { //returns a BigInt let res = BigInt(0); const radix = BigInt(0x100000000); for (let i = 0; i < arr.length; i++) { res = res * radix + BigInt(arr[i]); } return res; } function flatArray(a) { const res = []; fillArray(res, a); return res; function fillArray(res, a) { if (Array.isArray(a)) { for (let i = 0; i < a.length; i++) { fillArray(res, a[i]); } } else { res.push(a); } } } function fnvHash(str) { const uint64_max = BigInt(2) ** BigInt(64); let hash = BigInt('0xCBF29CE484222325'); for (let i = 0; i < str.length; i++) { hash ^= BigInt(str[i].charCodeAt()); hash *= BigInt(0x100000001b3); hash %= uint64_max; } let hashHex = hash.toString(16); const n = 16 - hashHex.length; hashHex = '0'.repeat(n).concat(hashHex); return hashHex; }