circom_tester/c/tester.js
c/tester.jsRaw
1const chai = require("chai");
2const assert = chai.assert;
3
4const fs = require("fs");
5var tmp = require("tmp-promise");
6const path = require("path");
7
8const util = require("util");
9const exec = util.promisify(require("child_process").exec);
10
11const loadR1cs = require("r1csfile").load;
12const ZqField = require("ffjavascript").ZqField;
13
14const readWtns = require("snarkjs").wtns.exportJson;
15
16module.exports = c_tester;
17
18async function c_tester(circomInput, _options) {
19
20 assert(await compiler_above_version("2.0.0"),"Wrong compiler version. Must be at least 2.0.0");
21
22 tmp.setGracefulCleanup();
23
24 const dir = await tmp.dir({prefix: "circom_", unsafeCleanup: true });
25
26 // console.log(dir.path);
27
28 const baseName = path.basename(circomInput, ".circom");
29 const options = Object.assign({}, _options);
30
31 options.wasm = true;
32
33 options.sym = true;
34 options.json = options.json || false; // costraints in json format
35 //options.r1cs = options.r1cs || false; // costraints in r1cs format
36 //if (!options.json) options.r1cs = true; // r1cs if not json
37 options.r1cs = true;
38 options.output = dir.path;
39
40 await compile(baseName, circomInput, options);
41
42 return new WasmTester(dir, baseName, run);
43}
44
45async function compile (baseName, fileName, options) {
46 var flags = "--c ";
47 if (options.sym) flags += "--sym ";
48 if (options.r1cs) flags += "--r1cs ";
49 if (options.json) flags += "--json ";
50 if (options.output) flags += "--output " + options.output + " ";
51 if (options.O === 0) flags += "--O0 "
52 if (options.O === 1) flags += "--O1 "
53
54 b = await exec("circom " + flags + fileName);
55 assert(b.stderr == "",
56 "circom compiler error \n" + b.stderr);
57
58 const c_folder = path.join(options.output, baseName+"_cpp/")
59 b = await exec("make -C "+c_folder);
60 assert(b.stderr == "",
61 "error building the executable C program\n" + b.stderr);
62}
63
64class WasmTester {
65
66 constructor(dir, baseName, witnessCalculator) {
67 this.dir=dir;
68 this.baseName = baseName;
69 this.witnessCalculator = witnessCalculator;
70 }
71
72 async release() {
73 await this.dir.cleanup();
74 }
75
76 async calculateWitness(input) {
77 const inputjson = JSON.stringify(input);
78 const inputFile = path.join(this.dir.path, this.baseName+"_cpp/" + this.baseName + ".json");
79 const wtnsFile = path.join(this.dir.path, this.baseName+"_cpp/" + this.baseName + ".wtns");
80 const runc = path.join(this.dir.path, this.baseName+"_cpp/" + this.baseName);
81 fs.writeFile(inputFile, inputjson, function(err) {
82 if (err) throw err;
83 });
84 await exec("ls " + path.join(this.dir.path, this.baseName+"_cpp/"));
85 await exec(runc + " " + inputFile + " " + wtnsFile);
86 return await readBinWitnessFile(wtnsFile);
87 }
88
89 async loadSymbols() {
90 if (this.symbols) return;
91 this.symbols = {};
92 const symsStr = await fs.promises.readFile(
93 path.join(this.dir.path, this.baseName + ".sym"),
94 "utf8"
95 );
96 const lines = symsStr.split("\n");
97 for (let i=0; i<lines.length; i++) {
98 const arr = lines[i].split(",");
99 if (arr.length!=4) continue;
100 this.symbols[arr[3]] = {
101 labelIdx: Number(arr[0]),
102 varIdx: Number(arr[1]),
103 componentIdx: Number(arr[2]),
104 };
105 }
106 }
107
108 async loadConstraints() {
109 const self = this;
110 if (this.constraints) return;
111 const r1cs = await loadR1cs(path.join(this.dir.path, this.baseName + ".r1cs"),true, false);
112 self.F = new ZqField(r1cs.prime);
113 self.nVars = r1cs.nVars;
114 self.constraints = r1cs.constraints;
115 }
116
117 async assertOut(actualOut, expectedOut) {
118 const self = this;
119 if (!self.symbols) await self.loadSymbols();
120
121 checkObject("main", expectedOut);
122
123 function checkObject(prefix, eOut) {
124
125 if (Array.isArray(eOut)) {
126 for (let i=0; i<eOut.length; i++) {
127 checkObject(prefix + "["+i+"]", eOut[i]);
128 }
129 } else if ((typeof eOut == "object")&&(eOut.constructor.name == "Object")) {
130 for (let k in eOut) {
131 checkObject(prefix + "."+k, eOut[k]);
132 }
133 } else {
134 if (typeof self.symbols[prefix] == "undefined") {
135 assert(false, "Output variable not defined: "+ prefix);
136 }
137 const ba = actualOut[self.symbols[prefix].varIdx].toString();
138 const be = eOut.toString();
139 assert.strictEqual(ba, be, prefix);
140 }
141 }
142 }
143
144 async getDecoratedOutput(witness) {
145 const self = this;
146 const lines = [];
147 if (!self.symbols) await self.loadSymbols();
148 for (let n in self.symbols) {
149 let v;
150 if (utils.isDefined(witness[self.symbols[n].varIdx])) {
151 v = witness[self.symbols[n].varIdx].toString();
152 } else {
153 v = "undefined";
154 }
155 lines.push(`${n} --> ${v}`);
156 }
157 return lines.join("\n");
158 }
159
160 async checkConstraints(witness) {
161 const self = this;
162 if (!self.constraints) await self.loadConstraints();
163 for (let i=0; i<self.constraints.length; i++) {
164 checkConstraint(self.constraints[i]);
165 }
166
167 function checkConstraint(constraint) {
168
169 const F = self.F;
170 const a = evalLC(constraint[0]);
171 const b = evalLC(constraint[1]);
172 const c = evalLC(constraint[2]);
173 assert (F.isZero(F.sub(F.mul(a,b), c)), "Constraint doesn't match");
174 }
175
176 function evalLC(lc) {
177 const F = self.F;
178 let v = F.zero;
179 for (let w in lc) {
180 v = F.add(
181 v,
182 F.mul( lc[w], witness[w] )
183 );
184 }
185 return v;
186 }
187 }
188
189}
190
191function version_to_list ( v ) {
192 return v.split(".").map(function(x) {
193 return parseInt(x, 10);
194 });
195}
196
197function check_versions ( v1, v2 ) {
198 //check if v1 is newer than or equal to v2
199 for (let i = 0; i < v2.length; i++) {
200 if (v1[i] > v2[i]) return true;
201 if (v1[i] < v2[i]) return false;
202 }
203 return true;
204}
205
206async function compiler_above_version(v) {
207 let output = await exec('circom --version').toString();
208 let compiler_version = version_to_list(output.slice(output.search(/\d/),-1));
209 vlist = version_to_list(v);
210 return check_versions ( compiler_version, vlist );
211}
212
213async function readBinWitnessFile(fileName) {
214 const buffWitness = await readWtns(fileName);
215 return buffWitness;
216}
217
218function fromArray8(arr) { //returns a BigInt
219 var res = BigInt(0);
220 const radix = BigInt(0x100);
221 for (let i = arr.length-1 ; i>=0; i--) {
222 res = res*radix + BigInt(arr[i]);
223 }
224 return res;
225}
226
227function fromArray8ToUint(arr) { //returns a BigInt
228 var res = 0;
229 const radix = 8;
230 for (let i = arr.length-1 ; i>=0; i--) {
231 res = res*radix + arr[i];
232 }
233 return res;
234}