First Version SMT

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Jordi Baylina 2018-12-11 17:25:21 +01:00
parent 2d43178c8d
commit 38fc4b7396
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15 changed files with 495 additions and 122321 deletions

122243
circuit.json

File diff suppressed because one or more lines are too long

@ -18,6 +18,7 @@
*/
include "comparators.circom";
include "aliascheck.circom";
template Num2Bits(n) {
@ -32,7 +33,20 @@ template Num2Bits(n) {
}
lc1 === in;
}
template Num2Bits_strict() {
signal input in;
signal output out[254];
component aliasCheck = AliasCheck();
component n2b = Num2Bits(254);
in ==> n2b.in;
for (var i=0; i<254; i++) {
n2b.out[i] ==> out[i];
n2b.out[i] ==> aliasCheck.in[i];
}
}
template Bits2Num(n) {
@ -47,6 +61,21 @@ template Bits2Num(n) {
lc1 ==> out;
}
template Bits2Num_strict() {
signal input in[n];
signal output out;
component aliasCheck = AliasCheck();
component b2n = Bits2Num(254);
for (var i=0; i<254; i++) {
in[i] ==> b2n.in[i];
in[i] ==> aliasCheck.in[i];
}
b2n.out ==> out;
}
template Num2BitsNeg(n) {
signal input in;
signal output out[n];

@ -0,0 +1,48 @@
include "../mimc.circom";
/*
Hash1 = H(1 | key | value)
*/
template SMTHash1() {
signal input key;
signal input value;
signal output out;
component h1 = MiMC7(91); // Constant
h1.x_in <== 0;
h1.k <== 1;
component h2 = MiMC7(91);
h2.x_in <== h1.out;
h2.k <== key;
component h3 = MiMC7(91);
h3.x_in <== h2.out;
h3.k <== value;
out <== h3.out;
}
/*
This component is used to create the 2 nodes.
Hash2 = H(Hl | Hr)
*/
template SMTHash2() {
signal input L;
signal input R;
signal output out;
component h1 = MiMC7(91);
h1.x_in <== 0;
h1.k <== L;
component h2 = MiMC7(91);
h2.x_in <== h1.out;
h2.k <== R;
out <== h2.out;
}

@ -96,65 +96,72 @@ Insert to a used leaf.
***************************************************************************************************/
include "../node_modules/circom/circuits/gates.circom";
include "../node_modules/circom/circuits/bitify.circom";
include "../gates.circom";
include "../bitify.circom";
include "../comparators.circom";
include "../switcher.circom";
include "smtlevins.circom";
include "smtinsertlevel.circom";
include "smtinsertsm.circom";
include "smthash.circom";
template SMTInsert(nLevels) {
signal input oldRoot;
signal input newRoot;
signal input siblings[nLevels];
signal input oldHKey;
signal input oldHValue;
signal input newHKey;
signal input newHValue;
signal input oldKey;
signal input oldValue;
signal input isOld0;
signal input newKey;
signal input newValue;
component hash1Old = SMTHash1();
hash1Old.l <== oldHKey;
hash1Old.r <== oldHValue;
hash1Old.key <== oldKey;
hash1Old.value <== oldValue;
component hash1New = SMTHash1();
hash1New.l <== newHKey;
hash1New.r <== newHValue;
hash1New.key <== newKey;
hash1New.value <== newValue;
component n2bOld = Num2BinStrinct();
component n2bNew = Num2BinStrinct();
component n2bOld = Num2Bits_strict();
component n2bNew = Num2Bits_strict();
component dmtLevIns = SMTLevIns(nLevels);
for (var i=0; i<nLevels; i++) dmtLevIns.siblings[i] <== siblings[i];
n2bOld.in <== oldKey;
n2bNew.in <== newKey;
component smtLevIns = SMTLevIns(nLevels);
for (var i=0; i<nLevels; i++) smtLevIns.siblings[i] <== siblings[i];
component xors[nLevels];
for (var i=0; i<nLevels; i++) {
xors[i] = XOR();
xors[i].a <== n2bOld.out[i];
xors[i].a <== n2bNew.out[i];
xors[i].b <== n2bNew.out[i];
}
component isOld0 = IsZero();
isOld0.in <== oldHValue;
component sm[nLevels];
for (var i=0; i<sm; i++) {
for (var i=0; i<nLevels; i++) {
sm[i] = SMTInsertSM();
if (i==0) {
sm[i].prevst_top <== 1;
sm[i].prevst_old1 <== 0;
sm[i].prevst_old0 <== 0;
sm[i].prevst_bot <== 0;
sm[i].prevst_new1 <== 0;
sm[i].prevst_na <== 0;
sm[i].prev_top <== 1;
sm[i].prev_old1 <== 0;
sm[i].prev_old0 <== 0;
sm[i].prev_bot <== 0;
sm[i].prev_new1 <== 0;
sm[i].prev_na <== 0;
} else {
sm[i].prevst_top <== sm[i-1].st_top;
sm[i].prevst_old1 <== sm[i-1].st_old1;
sm[i].prevst_old0 <== sm[i-1].st_old0;
sm[i].prevst_bot <== sm[i-1].st_bot;
sm[i].prevst_new1 <== sm[i-1].st_new1;
sm[i].prevst_na <== sm[i-1].st_na;
sm[i].prev_top <== sm[i-1].st_top;
sm[i].prev_old1 <== sm[i-1].st_old1;
sm[i].prev_old0 <== sm[i-1].st_old0;
sm[i].prev_bot <== sm[i-1].st_bot;
sm[i].prev_new1 <== sm[i-1].st_new1;
sm[i].prev_na <== sm[i-1].st_na;
}
sm[i].is0 <== isOld0.out;
sm[i].is0 <== isOld0;
sm[i].xor <== xors[i].out;
sm[i].levIns <== dmtLevIns.out[i];
sm[i].levIns <== smtLevIns.levIns[i];
}
sm[nLevels-1].prevst_na === 1;
sm[nLevels-1].st_na === 1;
component levels[nLevels];
for (var i=nLevels-1; i != -1; i--) {
@ -171,7 +178,7 @@ template SMTInsert(nLevels) {
levels[i].old1leaf <== hash1Old.out;
levels[i].new1leaf <== hash1New.out;
levels[i].new1lrbit <== n2bNew.out[i];
levels[i].newlrbit <== n2bNew.out[i];
if (i==nLevels-1) {
levels[i].oldChild <== 0;
levels[i].newChild <== 0;

@ -49,27 +49,27 @@ template SMTInsertLevel() {
// Old side
oldSwitcher.inL <== oldChild;
oldSwitcher.inR <== sibling;
oldSwitcher.L <== oldChild;
oldSwitcher.R <== sibling;
oldSwitcher.sel <== newlrbit;
oldProofHash.L <== oldSwitcher.outL;
oldProofHash.R <== oldSwitcher.outR;
aux[0] <== old1 * st_old1;
aux[0] <== old1leaf * st_old1;
oldRoot <== aux[0] + oldProofHash.out * st_top;
// New side
aux[1] <== newChild * ( st_top + st_old1 + st_but);
oldSwitcher.inL <== aux[1] + new1leaf*st_new1;
aux[1] <== newChild * ( st_top + st_old1 + st_bot);
newSwitcher.L <== aux[1] + new1leaf*st_new1;
aux[2] <== sibling*st_top;
oldSwitcher.inR <== aux[2] + old1leaf*st_new1;
newSwitcher.R <== aux[2] + old1leaf*st_new1;
newProofHash.sel <== newlrbit;
newProofHash.L <== newProofHash.outL;
newProofHash.R <== newProofHash.outR;
newSwitcher.sel <== newlrbit;
newProofHash.L <== newSwitcher.outL;
newProofHash.R <== newSwitcher.outR;
aux[3] <== newProofHash.out * (st_top + st_old1 + st_bot + st_new1);
newRoot <== aux[3] + new1leaf * st_old0;

@ -23,29 +23,37 @@ old and the new trees with just one element.
na: Not appliable. After inserting it, we go to the na level.
Fnction
fnc[0] fnc[1]
0 0 NOP
0 1 UPDATE
1 0 INSERT
1 1 DELETE
###########
levIns==curLevel # #
xor=0 is0=1 ┌────────────▶# old0 #────────┐
┌─────┐ │ ## ## │
│ │ │ ######### │ any
│ ▼ │ │
│ ########### │ │ ###########
│ # # ────────────┘ └────────▶# #
levIns=1 # #
levIns=0 is0=1 ┌────────────▶# old0 #────────┐ any
┌─────┐ │ ## ## │ ┌──────┐
│ │ │ ######### │ any │ │
│ ▼ │ │ ▼ │
│ ########### │ │ ###########
│ # # ────────────┘ └────────▶# #
└──# top # # na #
## ## ────┐ ┌──▶## ##
######### │ │ #########
│ │
│ ########### ########### │ any
levIns==curLevel │ # # xor=1 # # │
levIns=1 │ # # xor=1 # # │
is0=0 └───▶# old1 #─────────────▶# new1 #──┘
## ## ## ##
#########──┐ #########
┌─────┘
any ###########│ xor=1
# #
└─▶# btn #
######### #########
└───┐ ┌─────┘
xor=0 │ ###########│ xor=1
# #
# btn #
## ##
#########◀───────┐
│ │
@ -55,4 +63,47 @@ na: Not appliable. After inserting it, we go to the na level.
***************************************************************************************************/
state
template SMTInsertSM() {
signal input xor;
signal input is0;
signal input levIns;
signal input fnc[0];
signal input fnc[1];
signal input prev_top;
signal input prev_old0;
signal input prev_old1;
signal input prev_bot;
signal input prev_new1;
signal input prev_na;
signal input prev_upd;
signal output st_top;
signal output st_old0;
signal output st_old1;
signal output st_bot;
signal output st_new1;
signal output st_na;
signal output st_upd;
signal aux1;
signal aux2;
aux1 <== prev_top * levIns;
aux2 <== aux1*is0;
st_top <== prev_top - aux1 // prev_top * (1-levIns) =
// = prev_top - aux1;
st_old0 <== aux2 * fnc[0]; // (prev_top * levIns * is0)*fnc[0] = aux2
st_old1 <== (aux1 - aux2)*fnc[0]; // (prev_top * levIns * (1-is0))*fnc[0] =
// = (aux1 * (1-is0))*fnc[0] =
// = (aux1 - aux2) * fnc[0]
st_new1 <== (prev_old1 + prev_bot)*xor // prev_old1*xor + prev_bot*xor =
// = (prev_old1 + prev_bot)*xor;
st_bot <== -st_new1 + prev_old1 + prev_bot // prev_old1*(1-xor) + prev_bot*(1-xor) =
// = - prev_old1*xor -prev_bot*xor + prev_old1 + prev_bot =
// = -st_new1 + prev_old1 + prev_bot
st_na <== prev_new1 + prev_old0 + prev_na + st_upd;
st_upd <== aux1*(1-fnc[0]); // prev_top*levIns*(1-fnc[0]) =
// = aux1 * (1-fnc[0])
}

@ -55,7 +55,7 @@ a parent with a sibling != 0.
*/
template SMTLevIns(nLevels) {
signal input siblins[nLevels];
signal input siblings[nLevels];
signal output levIns[nLevels];
signal done[nLevels-1]; // Indicates if the insLevel has aready been detecetd.

21
circuits/switcher.circom Normal file

@ -0,0 +1,21 @@
/*
Assume sel is binary.
If sel == 0 then outL = L and outR=R
If sel == 1 then outL = R and outR=L
*/
template Switcher() {
signal input sel;
signal input L;
signal input R;
signal output outL;
signal output outR;
signal aux;
aux <== (R-L)*sel; // We create aux in order to have only one multiplication
outL <== aux + L;
outR <== -aux + R;
}

@ -1,18 +0,0 @@
const mimc = require("./mimc7");
const SEED = "iden3_mimc";
let nRounds;
if (typeof process.argv[2] != "undefined") {
nRounds = parseInt(process.argv[2]);
} else {
nRounds = 256;
}
const cts = mimc.getConstants(SEED, nRounds);
for (let i=0; i<nRounds; i++) {
let S = cts[i];
if (i<nRounds-1) S=S+",";
console.log(S);
}

157
src/smt.js Normal file

@ -0,0 +1,157 @@
const bigInt = require("snarkjs").bigInt;
const SMTMemDB = require("./smt_memdb");
const mimc7 = require("./mimc7");
function smtHash(arr) {
let r = bigInt(0);
for (let i=0; i<arr.length; i++) {
r = mimc7.hash(r, bigInt(arr[i]), 91 );
}
return r;
}
class SMT {
constructor(db, root) {
this.db = db;
this.root = root;
}
_splitBits(_key) {
let k = bigInt(_key);
const res = [];
while (!k.isZero()) {
if (k.isOdd()) {
res.push(true);
} else {
res.push(false);
}
k = k.shr(1);
}
while (res.length<256) res.push(false);
return res;
}
async insert(_key, _value) {
const key = bigInt(_key);
const value = bigInt(_value);
let addedOne = false;
const res = {};
res.oldRoot = this.root;
const newKeyBits = this._splitBits(key);
const resFind = await this.find(key);
if (resFind.found) throw new Error("Key already exists");
res.sibblings = resFind.sibblings;
if (!resFind.isOld0) {
const oldKeyits = this._splitBits(resFind.notFoundKey);
for (let i= res.sibblings.length; oldKeyits[i] == newKeyBits[i]; i++) {
res.sibblings.push(bigInt.zero);
}
res.sibblings.push(smtHash([1, resFind.notFoundKey, resFind.notFoundValue]));
addedOne = true;
}
const inserts = [];
let rt = smtHash([1, key, value]);
inserts.push([rt,[1, key, value]] );
for (let i=res.sibblings.length-1; i>=0; i--) {
if (newKeyBits[i]) {
rt = smtHash([res.sibblings[i], rt]);
inserts.push([rt,[res.sibblings[i], rt]] );
} else {
rt = smtHash([rt, res.sibblings[i]]);
inserts.push([rt,[rt, res.sibblings[i]]] );
}
}
if (addedOne) res.sibblings.pop();
while ((res.sibblings.length>0) && (res.sibblings[res.sibblings.length-1].isZero())) {
res.sibblings.pop();
}
res.oldKey = resFind.notFoundKey;
res.oldValue = resFind.notFoundValue;
res.newRoot = rt;
res.isOld0 = resFind.isOld0;
this.root = rt;
await this.db.save(rt, inserts);
return res;
}
async find(key) {
const keyBits = this._splitBits(key);
return await this._find(key, keyBits, this.root, 0);
}
async _find(key, keyBits, root, level) {
if (typeof root === "undefined") root = this.root;
let res;
if (root.isZero()) {
res = {
found: false,
sibblings: [],
notFoundKey: key,
notFoundValue: bigInt.zero,
isOld0: true
};
return res;
}
const record = await this.db.get(root);
if ((record.length==3)&&(record[0].equals(bigInt.one))) {
if (record[1].equals(key)) {
res = {
found: true,
sibblings: [],
foundValue: record[2],
isOld0: false
};
} else {
res = {
found: false,
sibblings: [],
notFoundKey: record[1],
notFoundValue: record[2],
isOld0: false
};
}
} else {
if (keyBits[level] == 0) {
const res = await this.find(key, keyBits, record[1], level+1);
res.sibblings.unshift(record[2]);
} else {
res = await this.find(key, keyBits, record[2], level+1);
res.sibblings.unshift(record[1]);
}
}
return res;
}
}
async function loadFromFile(fileName) {
}
async function newMemEmptyTrie() {
const db = new SMTMemDB();
const rt = await db.getRoot();
const smt = new SMT(db, rt);
return smt;
}
module.exports.loadFromFile = loadFromFile;
module.exports.newMemEmptyTrie = newMemEmptyTrie;

31
src/smt_memdb.js Normal file

@ -0,0 +1,31 @@
const bigInt = require("snarkjs").bigInt;
class SMTMemDb {
constructor() {
this.nodes = {};
this.root = bigInt(0);
}
async getRoot() {
return this.root;
}
async get(key) {
const res = [];
const keyS = bigInt(key).leInt2Buff(32).toString("hex");
for (let i=0; i<this.nodes[keyS].length; i++) {
res.push(bigInt(this.nodes[keyS][i]));
}
return res;
}
async save(root, inserts) {
for (let i=0; i<inserts.length; i++) {
const keyS = bigInt(inserts[i][0]).leInt2Buff(32).toString("hex");
this.nodes[keyS] = inserts[i][1];
}
this.root = root;
}
}
module.exports = SMTMemDb;

@ -0,0 +1,3 @@
include "../../circuits/smt/smtinsert.circom";
component main = SMTInsert(10);

88
test/smt.js Normal file

@ -0,0 +1,88 @@
const chai = require("chai");
const path = require("path");
const snarkjs = require("snarkjs");
const compiler = require("circom");
const smt = require("../src/smt.js");
const assert = chai.assert;
const bigInt = snarkjs.bigInt;
function print(circuit, w, s) {
console.log(s + ": " + w[circuit.getSignalIdx(s)]);
}
describe("SMT test", function () {
let circuit;
let tree;
this.timeout(100000);
before( async () => {
const cirDef = await compiler(path.join(__dirname, "circuits", "smtinsert10_test.circom"));
circuit = new snarkjs.Circuit(cirDef);
console.log("NConstrains SMTInsert: " + circuit.nConstraints);
tree = await smt.newMemEmptyTrie();
});
it("Should verify an insert to an empty tree", async () => {
const key = bigInt(111);
const value = bigInt(222);
const res = await tree.insert(key,value);
let siblings = res.sibblings;
while (siblings.length<10) siblings.push(bigInt(0));
const w = circuit.calculateWitness({
oldRoot: res.oldRoot,
newRoot: res.newRoot,
siblings: siblings,
oldKey: res.oldKey,
oldValue: res.oldValue,
isOld0: res.isOld0 ? 1 : 0,
newKey: key,
newValue: value
});
const root1 = w[circuit.getSignalIdx("main.levels[0].newRoot")];
console.log("root1: " + root1.toString());
console.log("root2: " + res.newRoot.toString());
assert(root1.equals(res.newRoot));
assert(circuit.checkWitness(w));
});
it("It should add another element", async () => {
const key = bigInt(333);
const value = bigInt(444);
const res = await tree.insert(key,value);
let siblings = res.sibblings;
while (siblings.length<10) siblings.push(bigInt(0));
const w = circuit.calculateWitness({
oldRoot: res.oldRoot,
newRoot: res.newRoot,
siblings: siblings,
oldKey: res.oldKey,
oldValue: res.oldValue,
isOld0: res.isOld0 ? 1 : 0,
newKey: key,
newValue: value
});
const root1 = w[circuit.getSignalIdx("main.levels[0].newRoot")];
console.log("root1: " + root1.toString());
console.log("root2: " + res.newRoot.toString());
assert(root1.equals(res.newRoot));
assert(circuit.checkWitness(w));
});
});