wallet-core/extension/lib/wallet/wallet.ts
Florian Dold 0f607edbb2 debug
2016-02-17 18:59:27 +01:00

908 lines
24 KiB
TypeScript

/*
This file is part of TALER
(C) 2015 GNUnet e.V.
TALER is free software; you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation; either version 3, or (at your option) any later version.
TALER is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
TALER; see the file COPYING. If not, If not, see <http://www.gnu.org/licenses/>
*/
/**
* High-level wallet operations that should be indepentent from the underlying
* browser extension interface.
* @module Wallet
* @author Florian Dold
*/
import * as native from "./emscriptif";
import {AmountJson, CreateReserveResponse} from "./types";
import {HttpResponse, RequestException} from "./http";
import {Query} from "./query";
import {Checkable} from "./checkable";
import {canonicalizeBaseUrl} from "./helpers";
"use strict";
export interface Mint {
baseUrl: string;
keys: Keys
}
export interface CoinWithDenom {
coin: Coin;
denom: Denomination;
}
export interface Keys {
denoms: Denomination[];
}
export interface Denomination {
value: AmountJson;
denom_pub: string;
fee_withdraw: AmountJson;
fee_deposit: AmountJson;
stamp_expire_withdraw: string;
}
export interface PreCoin {
coinPub: string;
coinPriv: string;
reservePub: string;
denomPub: string;
blindingKey: string;
withdrawSig: string;
coinEv: string;
mintBaseUrl: string;
coinValue: AmountJson;
}
export interface Coin {
coinPub: string;
coinPriv: string;
denomPub: string;
denomSig: string;
currentAmount: AmountJson;
mintBaseUrl: string;
}
@Checkable.Class
export class CreateReserveRequest {
/**
* The initial amount for the reserve.
*/
@Checkable.Value(AmountJson)
amount: AmountJson;
/**
* Mint URL where the bank should create the reserve.
*/
@Checkable.String
mint: string;
static checked: (obj: any) => CreateReserveRequest;
}
@Checkable.Class
export class ConfirmReserveRequest {
/**
* Public key of then reserve that should be marked
* as confirmed.
*/
@Checkable.String
reservePub: string;
static checked: (obj: any) => ConfirmReserveRequest;
}
@Checkable.Class
export class MintInfo {
@Checkable.String
master_pub: string;
@Checkable.String
url: string;
static checked: (obj: any) => MintInfo;
}
@Checkable.Class
export class Contract {
@Checkable.String
H_wire: string;
@Checkable.Value(AmountJson)
amount: AmountJson;
@Checkable.List(Checkable.AnyObject)
auditors: any[];
@Checkable.String
expiry: string;
@Checkable.Any
locations: any;
@Checkable.Value(AmountJson)
max_fee: AmountJson;
@Checkable.Any
merchant: any;
@Checkable.String
merchant_pub: string;
@Checkable.List(Checkable.Value(MintInfo))
mints: MintInfo[];
@Checkable.List(Checkable.AnyObject)
products: any[];
@Checkable.String
refund_deadline: string;
@Checkable.String
timestamp: string;
@Checkable.Number
transaction_id: number;
@Checkable.String
fulfillment_url: string;
@Checkable.Optional(Checkable.String)
repurchase_correlation_id: string;
static checked: (obj: any) => Contract;
}
@Checkable.Class
export class Offer {
@Checkable.Value(Contract)
contract: Contract;
@Checkable.String
merchant_sig: string;
@Checkable.String
H_contract: string;
static checked: (obj: any) => Offer;
}
interface ConfirmPayRequest {
offer: Offer;
}
interface MintCoins {
[mintUrl: string]: CoinWithDenom[];
}
interface CoinPaySig {
coin_sig: string;
coin_pub: string;
ub_sig: string;
denom_pub: string;
f: AmountJson;
}
interface Transaction {
contractHash: string;
contract: any;
payReq: any;
}
interface Reserve {
mint_base_url: string
reserve_priv: string;
reserve_pub: string;
}
export interface Badge {
setText(s: string): void;
setColor(c: string): void;
}
type PayCoinInfo = Array<{ updatedCoin: Coin, sig: CoinPaySig }>;
function getTalerStampSec(stamp: string) {
const m = stamp.match(/\/?Date\(([0-9]*)\)\/?/);
if (!m) {
return null;
}
return parseInt(m[1]);
}
function isWithdrawableDenom(d: Denomination) {
const now_sec = (new Date).getTime() / 1000;
const stamp_withdraw_sec = getTalerStampSec(d.stamp_expire_withdraw);
// Withdraw if still possible to withdraw within a minute
if (stamp_withdraw_sec + 60 > now_sec) {
return true;
}
return false;
}
interface HttpRequestLibrary {
req(method: string,
url: string|uri.URI,
options?: any): Promise<HttpResponse>;
get(url: string|uri.URI): Promise<HttpResponse>;
postJson(url: string|uri.URI, body): Promise<HttpResponse>;
postForm(url: string|uri.URI, form): Promise<HttpResponse>;
}
function copy(o) {
return JSON.parse(JSON.stringify(o));
}
/**
* Rank two denomination by how desireable it is to withdraw them,
* based on their fees and value.
*/
function rankDenom(denom1: any, denom2: any) {
// Slow ... we should find a better way than to convert it evert time.
let v1 = new native.Amount(denom1.value);
let v2 = new native.Amount(denom2.value);
return (-1) * v1.cmp(v2);
}
/**
* Create a pre-coin of the given denomination to be withdrawn from then given
* reserve.
*/
function createPreCoin(denom: Denomination, reserve: Reserve): PreCoin {
let reservePriv = new native.EddsaPrivateKey();
reservePriv.loadCrock(reserve.reserve_priv);
let reservePub = new native.EddsaPublicKey();
reservePub.loadCrock(reserve.reserve_pub);
let denomPub = native.RsaPublicKey.fromCrock(denom.denom_pub);
let coinPriv = native.EddsaPrivateKey.create();
let coinPub = coinPriv.getPublicKey();
let blindingFactor = native.RsaBlindingKey.create(1024);
let pubHash: native.HashCode = coinPub.hash();
let ev: native.ByteArray = native.rsaBlind(pubHash,
blindingFactor,
denomPub);
if (!denom.fee_withdraw) {
throw Error("Field fee_withdraw missing");
}
let amountWithFee = new native.Amount(denom.value);
amountWithFee.add(new native.Amount(denom.fee_withdraw));
let withdrawFee = new native.Amount(denom.fee_withdraw);
// Signature
let withdrawRequest = new native.WithdrawRequestPS({
reserve_pub: reservePub,
amount_with_fee: amountWithFee.toNbo(),
withdraw_fee: withdrawFee.toNbo(),
h_denomination_pub: denomPub.encode().hash(),
h_coin_envelope: ev.hash()
});
var sig = native.eddsaSign(withdrawRequest.toPurpose(), reservePriv);
let preCoin: PreCoin = {
reservePub: reservePub.toCrock(),
blindingKey: blindingFactor.toCrock(),
coinPub: coinPub.toCrock(),
coinPriv: coinPriv.toCrock(),
denomPub: denomPub.encode().toCrock(),
mintBaseUrl: reserve.mint_base_url,
withdrawSig: sig.toCrock(),
coinEv: ev.toCrock(),
coinValue: denom.value
};
return preCoin;
}
/**
* Get a list of denominations (with repetitions possible)
* whose total value is as close as possible to the available
* amount, but never larger.
*/
function getWithdrawDenomList(amountAvailable: AmountJson,
denoms: Denomination[]): Denomination[] {
let remaining = new native.Amount(amountAvailable);
let ds: Denomination[] = [];
denoms = denoms.filter(isWithdrawableDenom);
denoms.sort(rankDenom);
// This is an arbitrary number of coins
// we can withdraw in one go. It's not clear if this limit
// is useful ...
for (let i = 0; i < 1000; i++) {
let found = false;
for (let d of denoms) {
let cost = new native.Amount(d.value);
cost.add(new native.Amount(d.fee_withdraw));
if (remaining.cmp(cost) < 0) {
continue;
}
found = true;
remaining.sub(cost);
ds.push(d);
}
if (!found) {
console.log("did not find coins for remaining ", remaining.toJson());
break;
}
}
return ds;
}
export class Wallet {
private db: IDBDatabase;
private http: HttpRequestLibrary;
private badge: Badge;
constructor(db: IDBDatabase, http: HttpRequestLibrary, badge: Badge) {
this.db = db;
this.http = http;
this.badge = badge;
}
/**
* Generate updated coins (to store in the database)
* and deposit permissions for each given coin.
*/
private static signDeposit(offer: Offer,
cds: CoinWithDenom[]): PayCoinInfo {
let ret = [];
let amountSpent = native.Amount.getZero(cds[0].coin.currentAmount.currency);
let amountRemaining = new native.Amount(offer.contract.amount);
cds = copy(cds);
for (let cd of cds) {
let coinSpend;
if (amountRemaining.value == 0 && amountRemaining.fraction == 0) {
break;
}
if (amountRemaining.cmp(new native.Amount(cd.coin.currentAmount)) < 0) {
coinSpend = new native.Amount(amountRemaining.toJson());
} else {
coinSpend = new native.Amount(cd.coin.currentAmount);
}
amountSpent.add(coinSpend);
amountRemaining.sub(coinSpend);
let newAmount = new native.Amount(cd.coin.currentAmount);
newAmount.sub(coinSpend);
cd.coin.currentAmount = newAmount.toJson();
let d = new native.DepositRequestPS({
h_contract: native.HashCode.fromCrock(offer.H_contract),
h_wire: native.HashCode.fromCrock(offer.contract.H_wire),
amount_with_fee: coinSpend.toNbo(),
coin_pub: native.EddsaPublicKey.fromCrock(cd.coin.coinPub),
deposit_fee: new native.Amount(cd.denom.fee_deposit).toNbo(),
merchant: native.EddsaPublicKey.fromCrock(offer.contract.merchant_pub),
refund_deadline: native.AbsoluteTimeNbo.fromTalerString(offer.contract.refund_deadline),
timestamp: native.AbsoluteTimeNbo.fromTalerString(offer.contract.timestamp),
transaction_id: native.UInt64.fromNumber(offer.contract.transaction_id),
});
let coinSig = native.eddsaSign(d.toPurpose(),
native.EddsaPrivateKey.fromCrock(cd.coin.coinPriv))
.toCrock();
let s: CoinPaySig = {
coin_sig: coinSig,
coin_pub: cd.coin.coinPub,
ub_sig: cd.coin.denomSig,
denom_pub: cd.coin.denomPub,
f: coinSpend.toJson(),
};
ret.push({sig: s, updatedCoin: cd.coin});
}
return ret;
}
/**
* Get mints and associated coins that are still spendable,
* but only if the sum the coins' remaining value exceeds the payment amount.
*/
private getPossibleMintCoins(paymentAmount: AmountJson,
depositFeeLimit: AmountJson,
allowedMints: MintInfo[]): Promise<MintCoins> {
// Mapping from mint base URL to list of coins together with their
// denomination
let m: MintCoins = {};
function storeMintCoin(mc) {
let mint = mc[0];
let coin = mc[1];
let cd = {
coin: coin,
denom: mint.keys.denoms.find((e) => e.denom_pub === coin.denomPub)
};
if (!cd.denom) {
throw Error("denom not found (database inconsistent)");
}
let x = m[mint.baseUrl];
if (!x) {
m[mint.baseUrl] = [cd];
} else {
x.push(cd);
}
}
let ps = allowedMints.map((info) => {
return Query(this.db)
.iter("mints", {indexName: "pubKey", only: info.master_pub})
.indexJoin("coins", "mintBaseUrl", (mint) => mint.baseUrl)
.reduce(storeMintCoin);
});
return Promise.all(ps).then(() => {
let ret: MintCoins = {};
if (Object.keys(m).length == 0) {
console.log("not suitable mints found");
}
console.dir(m);
// We try to find the first mint where we have
// enough coins to cover the paymentAmount with fees
// under depositFeeLimit
nextMint:
for (let key in m) {
let coins = m[key].map((x) => ({
a: new native.Amount(x.denom.fee_deposit),
c: x
}));
// Sort by ascending deposit fee
coins.sort((o1, o2) => o1.a.cmp(o2.a));
let maxFee = new native.Amount(depositFeeLimit);
let minAmount = new native.Amount(paymentAmount);
let accFee = new native.Amount(coins[0].c.denom.fee_deposit);
let accAmount = native.Amount.getZero(coins[0].c.coin.currentAmount.currency);
let usableCoins: CoinWithDenom[] = [];
nextCoin:
for (let i = 0; i < coins.length; i++) {
let coinAmount = new native.Amount(coins[i].c.coin.currentAmount);
let coinFee = coins[i].a;
if (coinAmount.cmp(coinFee) <= 0) {
continue nextCoin;
}
accFee.add(coinFee);
accAmount.add(coinAmount);
if (accFee.cmp(maxFee) >= 0) {
// FIXME: if the fees are too high, we have
// to cover them ourselves ....
console.log("too much fees");
continue nextMint;
}
usableCoins.push(coins[i].c);
if (accAmount.cmp(minAmount) >= 0) {
ret[key] = usableCoins;
continue nextMint;
}
}
}
return ret;
});
}
/**
* Record all information that is necessary to
* pay for a contract in the wallet's database.
*/
private recordConfirmPay(offer: Offer,
payCoinInfo: PayCoinInfo,
chosenMint: string): Promise<void> {
let payReq = {};
payReq["amount"] = offer.contract.amount;
payReq["coins"] = payCoinInfo.map((x) => x.sig);
payReq["H_contract"] = offer.H_contract;
payReq["max_fee"] = offer.contract.max_fee;
payReq["merchant_sig"] = offer.merchant_sig;
payReq["mint"] = URI(chosenMint).href();
payReq["refund_deadline"] = offer.contract.refund_deadline;
payReq["timestamp"] = offer.contract.timestamp;
payReq["transaction_id"] = offer.contract.transaction_id;
let t: Transaction = {
contractHash: offer.H_contract,
contract: offer.contract,
payReq: payReq,
};
let historyEntry = {
type: "pay",
timestamp: (new Date).getTime(),
detail: {
merchantName: offer.contract.merchant.name,
amount: offer.contract.amount,
contractHash: offer.H_contract,
fulfillmentUrl: offer.contract.fulfillment_url
}
};
return Query(this.db)
.put("transactions", t)
.put("history", historyEntry)
.putAll("coins", payCoinInfo.map((pci) => pci.updatedCoin))
.finish();
}
/**
* Add a contract to the wallet and sign coins,
* but do not send them yet.
*/
confirmPay(offer: Offer): Promise<any> {
console.log("executing confirmPay");
return Promise.resolve().then(() => {
return this.getPossibleMintCoins(offer.contract.amount,
offer.contract.max_fee,
offer.contract.mints)
}).then((mcs) => {
if (Object.keys(mcs).length == 0) {
console.log("not confirming payment, insufficient coins");
return {
error: "coins-insufficient",
};
}
console.log("about to record ...");
let mintUrl = Object.keys(mcs)[0];
let ds = Wallet.signDeposit(offer, mcs[mintUrl]);
return this.recordConfirmPay(offer, ds, mintUrl)
.then((() => ({})));
});
}
/**
* Retrieve all necessary information for looking up the contract
* with the given hash.
*/
executePayment(H_contract): Promise<any> {
return Promise.resolve().then(() => {
return Query(this.db)
.get("transactions", H_contract)
.then((t) => {
if (!t) {
return {
success: false,
contractFound: false,
}
}
let resp = {
success: true,
payReq: t.payReq,
contract: t.contract,
};
return resp;
});
});
}
/**
* First fetch information requred to withdraw from the reserve,
* then deplete the reserve, withdrawing coins until it is empty.
*/
private initReserve(reserveRecord) {
this.updateMintFromUrl(reserveRecord.mint_base_url)
.then((mint) =>
this.updateReserve(reserveRecord.reserve_pub, mint)
.then((reserve) => this.depleteReserve(reserve,
mint)))
.then(() => {
let depleted = {
type: "depleted-reserve",
timestamp: (new Date).getTime(),
detail: {
reservePub: reserveRecord.reserve_pub,
}
};
return Query(this.db).put("history", depleted).finish();
})
.catch((e) => {
console.error("Failed to deplete reserve", e.stack);
});
}
/**
* Create a reserve, but do not flag it as confirmed yet.
*/
createReserve(req: CreateReserveRequest): Promise<CreateReserveResponse> {
const reservePriv = native.EddsaPrivateKey.create();
const reservePub = reservePriv.getPublicKey();
const now = (new Date).getTime();
const canonMint = canonicalizeBaseUrl(req.mint);
const reserveRecord = {
reserve_pub: reservePub.toCrock(),
reserve_priv: reservePriv.toCrock(),
mint_base_url: canonMint,
created: now,
last_query: null,
current_amount: null,
requested_amount: req.amount,
confirmed: false,
};
const historyEntry = {
type: "create-reserve",
timestamp: now,
detail: {
requestedAmount: req.amount,
reservePub: reserveRecord.reserve_pub,
}
};
return Query(this.db)
.put("reserves", reserveRecord)
.put("history", historyEntry)
.finish()
.then(() => {
let r: CreateReserveResponse = {
mint: canonMint,
reservePub: reservePub.toCrock(),
};
return r;
});
}
/**
* Mark an existing reserve as confirmed. The wallet will start trying
* to withdraw from that reserve. This may not immediately succeed,
* since the mint might not know about the reserve yet, even though the
* bank confirmed its creation.
*
* A confirmed reserve should be shown to the user in the UI, while
* an unconfirmed reserve should be hidden.
*/
confirmReserve(req: ConfirmReserveRequest): Promise<void> {
const now = (new Date).getTime();
const historyEntry = {
type: "confirm-reserve",
timestamp: now,
detail: {
reservePub: req.reservePub,
}
};
return Query(this.db)
.get("reserves", req.reservePub)
.then((r) => {
r.confirmed = true;
return Query(this.db)
.put("reserves", r)
.put("history", historyEntry)
.finish()
.then(() => {
// Do this in the background
this.initReserve(r);
});
});
}
private withdrawExecute(pc: PreCoin): Promise<Coin> {
return Query(this.db)
.get("reserves", pc.reservePub)
.then((r) => {
let wd: any = {};
wd.denom_pub = pc.denomPub;
wd.reserve_pub = pc.reservePub;
wd.reserve_sig = pc.withdrawSig;
wd.coin_ev = pc.coinEv;
let reqUrl = URI("reserve/withdraw").absoluteTo(r.mint_base_url);
return this.http.postJson(reqUrl, wd);
})
.then(resp => {
if (resp.status != 200) {
throw new RequestException({
hint: "Withdrawal failed",
status: resp.status
});
}
let r = JSON.parse(resp.responseText);
let denomSig = native.rsaUnblind(native.RsaSignature.fromCrock(r.ev_sig),
native.RsaBlindingKey.fromCrock(pc.blindingKey),
native.RsaPublicKey.fromCrock(pc.denomPub));
let coin: Coin = {
coinPub: pc.coinPub,
coinPriv: pc.coinPriv,
denomPub: pc.denomPub,
denomSig: denomSig.encode().toCrock(),
currentAmount: pc.coinValue,
mintBaseUrl: pc.mintBaseUrl,
};
return coin;
});
}
storeCoin(coin: Coin): Promise<void> {
let historyEntry = {
type: "withdraw",
timestamp: (new Date).getTime(),
detail: {
coinPub: coin.coinPub,
}
};
return Query(this.db)
.delete("precoins", coin.coinPub)
.add("coins", coin)
.add("history", historyEntry)
.finish();
}
/**
* Withdraw one coins of the given denomination from the given reserve.
*/
private withdraw(denom: Denomination, reserve: Reserve): Promise<void> {
console.log("creating pre coin at", new Date());
let preCoin = createPreCoin(denom, reserve);
return Query(this.db)
.put("precoins", preCoin)
.finish()
.then(() => this.withdrawExecute(preCoin))
.then((c) => this.storeCoin(c));
}
/**
* Withdraw coins from a reserve until it is empty.
*/
private depleteReserve(reserve, mint: Mint): Promise<void> {
let denomsAvailable: Denomination[] = copy(mint.keys.denoms);
let denomsForWithdraw = getWithdrawDenomList(reserve.current_amount,
denomsAvailable);
let ps = denomsForWithdraw.map((denom) => {
console.log("withdrawing", JSON.stringify(denom));
// Do the withdraw asynchronously, so crypto is interleaved
// with requests
return this.withdraw(denom, reserve);
});
return Promise.all(ps).then(() => void 0);
}
/**
* Update the information about a reserve that is stored in the wallet
* by quering the reserve's mint.
*/
private updateReserve(reservePub: string, mint: Mint): Promise<Reserve> {
return Query(this.db)
.get("reserves", reservePub)
.then((reserve) => {
let reqUrl = URI("reserve/status").absoluteTo(mint.baseUrl);
reqUrl.query({'reserve_pub': reservePub});
return this.http.get(reqUrl).then(resp => {
if (resp.status != 200) {
throw Error();
}
let reserveInfo = JSON.parse(resp.responseText);
if (!reserveInfo) {
throw Error();
}
let oldAmount = reserve.current_amount;
let newAmount = reserveInfo.balance;
reserve.current_amount = reserveInfo.balance;
let historyEntry = {
type: "reserve-update",
timestamp: (new Date).getTime(),
detail: {
reservePub,
oldAmount,
newAmount
}
};
return Query(this.db)
.put("reserves", reserve)
.finish()
.then(() => reserve);
});
});
}
/**
* Update or add mint DB entry by fetching the /keys information.
* Optionally link the reserve entry to the new or existing
* mint entry in then DB.
*/
private updateMintFromUrl(baseUrl): Promise<Mint> {
let reqUrl = URI("keys").absoluteTo(baseUrl);
return this.http.get(reqUrl).then((resp) => {
if (resp.status != 200) {
throw Error("/keys request failed");
}
let mintKeysJson = JSON.parse(resp.responseText);
if (!mintKeysJson) {
throw new RequestException({url: reqUrl, hint: "keys invalid"});
}
let mint: Mint = {
baseUrl: baseUrl,
keys: mintKeysJson
};
return Query(this.db).put("mints", mint).finish().then(() => mint);
});
}
/**
* Retrieve a mapping from currency name to the amount
* that is currenctly available for spending in the wallet.
*/
getBalances(): Promise<any> {
function collectBalances(c: Coin, byCurrency) {
let acc: AmountJson = byCurrency[c.currentAmount.currency];
if (!acc) {
acc = native.Amount.getZero(c.currentAmount.currency).toJson();
}
let am = new native.Amount(c.currentAmount);
am.add(new native.Amount(acc));
byCurrency[c.currentAmount.currency] = am.toJson();
return byCurrency;
}
return Query(this.db)
.iter("coins")
.reduce(collectBalances, {});
}
/**
* Retrive the full event history for this wallet.
*/
getHistory(): Promise<any[]> {
function collect(x, acc) {
acc.push(x);
return acc;
}
return Query(this.db)
.iter("history", {indexName: "timestamp"})
.reduce(collect, [])
}
}