path: root/extension/background/wallet.js

/*
 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
 */
/// <reference path="../decl/urijs/URIjs.d.ts" />
/// <reference path="../decl/chrome/chrome.d.ts" />
'use strict';
/**
 * See http://api.taler.net/wallet.html#general
 */
function canonicalizeBaseUrl(url) {
    let x = new URI(url);
    if (!x.protocol()) {
        x.protocol("https");
    }
    x.path(x.path() + "/").normalizePath();
    x.fragment();
    x.query();
    return x.href();
}
function signDeposit(db, offer, cds) {
    let ret = [];
    let amountSpent = Amount.getZero(cds[0].coin.currentAmount.currency);
    let amountRemaining = new 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 Amount(cd.coin.currentAmount)) < 0) {
            coinSpend = new Amount(amountRemaining.toJson());
        }
        else {
            coinSpend = new Amount(cd.coin.currentAmount);
        }
        amountSpent.add(coinSpend);
        amountRemaining.sub(coinSpend);
        let newAmount = new Amount(cd.coin.currentAmount);
        newAmount.sub(coinSpend);
        cd.coin.currentAmount = newAmount.toJson();
        let args = {
            h_contract: HashCode.fromCrock(offer.H_contract),
            h_wire: HashCode.fromCrock(offer.contract.H_wire),
            amount_with_fee: coinSpend.toNbo(),
            coin_pub: EddsaPublicKey.fromCrock(cd.coin.coinPub),
            deposit_fee: new Amount(cd.denom.fee_deposit).toNbo(),
            merchant: EddsaPublicKey.fromCrock(offer.contract.merchant_pub),
            refund_deadline: AbsoluteTimeNbo.fromTalerString(offer.contract.refund_deadline),
            timestamp: AbsoluteTimeNbo.fromTalerString(offer.contract.timestamp),
            transaction_id: UInt64.fromNumber(offer.contract.transaction_id),
        };
        let d = new DepositRequestPS(args);
        let coinSig = eddsaSign(d.toPurpose(), EddsaPrivateKey.fromCrock(cd.coin.coinPriv))
            .toCrock();
        let s = {
            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.
 * @param db
 * @param paymentAmount
 * @param depositFeeLimit
 * @param allowedMints
 */
function getPossibleMintCoins(db, paymentAmount, depositFeeLimit, allowedMints) {
    let m = {};
    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(db)
            .iterIndex("mints", "pubKey", info.master_pub)
            .indexJoin("coins", "mintBaseUrl", (mint) => mint.baseUrl)
            .reduce(storeMintCoin);
    });
    return Promise.all(ps).then(() => {
        let ret = {};
        nextMint: for (let key in m) {
            let coins = m[key].map((x) => ({
                a: new Amount(x.denom.fee_deposit),
                c: x
            }));
            // Sort by ascending deposit fee
            coins.sort((o1, o2) => o1.a.cmp(o2.a));
            let maxFee = new Amount(depositFeeLimit);
            let minAmount = new Amount(paymentAmount);
            let accFee = new Amount(coins[0].c.denom.fee_deposit);
            let accAmount = Amount.getZero(coins[0].c.coin.currentAmount.currency);
            let usableCoins = [];
            nextCoin: for (let i = 0; i < coins.length; i++) {
                let coinAmount = new 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) {
                    console.log("too much fees");
                    continue nextMint;
                }
                usableCoins.push(coins[i].c);
                if (accAmount.cmp(minAmount) >= 0) {
                    ret[key] = usableCoins;
                    continue nextMint;
                }
            }
        }
        return ret;
    });
}
function executePay(db, offer, payCoinInfo, merchantBaseUrl, chosenMint) {
    let payReq = {};
    payReq["H_wire"] = offer.contract.H_wire;
    payReq["H_contract"] = offer.H_contract;
    payReq["transaction_id"] = offer.contract.transaction_id;
    payReq["refund_deadline"] = offer.contract.refund_deadline;
    payReq["mint"] = URI(chosenMint).href();
    payReq["coins"] = payCoinInfo.map((x) => x.sig);
    payReq["timestamp"] = offer.contract.timestamp;
    let payUrl = URI(offer.pay_url).absoluteTo(merchantBaseUrl);
    let t = {
        contractHash: offer.H_contract,
        contract: offer.contract,
        payUrl: payUrl.href(),
        payReq: payReq
    };
    return Query(db)
        .put("transactions", t)
        .putAll("coins", payCoinInfo.map((pci) => pci.updatedCoin))
        .finish();
}
function confirmPayHandler(db, detail, sendResponse) {
    let offer = detail.offer;
    getPossibleMintCoins(db, offer.contract.amount, offer.contract.max_fee, offer.contract.mints)
        .then((mcs) => {
        if (Object.keys(mcs).length == 0) {
            sendResponse({ error: "Not enough coins." });
            return;
        }
        let mintUrl = Object.keys(mcs)[0];
        let ds = signDeposit(db, offer, mcs[mintUrl]);
        return executePay(db, offer, ds, detail.merchantPageUrl, mintUrl)
            .then(() => {
            sendResponse({
                success: true,
            });
        });
    });
    return true;
}
function doPaymentHandler(db, detail, sendResponse) {
    let H_contract = detail.H_contract;
    Query(db)
        .get("transactions", H_contract)
        .then((r) => {
        if (!r) {
            sendResponse({ success: false, error: "contract not found" });
            return;
        }
        sendResponse({
            success: true,
            payUrl: r.payUrl,
            payReq: r.payReq
        });
    });
    // async sendResponse
    return true;
}
function confirmReserveHandler(db, detail, sendResponse) {
    let reservePriv = EddsaPrivateKey.create();
    let reservePub = reservePriv.getPublicKey();
    let form = new FormData();
    let now = (new Date()).toString();
    form.append(detail.field_amount, detail.amount_str);
    form.append(detail.field_reserve_pub, reservePub.toCrock());
    form.append(detail.field_mint, detail.mint);
    // XXX: set bank-specified fields.
    let mintBaseUrl = canonicalizeBaseUrl(detail.mint);
    httpPostForm(detail.post_url, form)
        .then((hresp) => {
        // TODO: extract as interface
        let resp = {
            status: hresp.status,
            text: hresp.responseText,
            success: undefined,
            backlink: undefined
        };
        let reserveRecord = {
            reserve_pub: reservePub.toCrock(),
            reserve_priv: reservePriv.toCrock(),
            mint_base_url: mintBaseUrl,
            created: now,
            last_query: null,
            current_amount: null,
            // XXX: set to actual amount
            initial_amount: null
        };
        if (hresp.status != 200) {
            resp.success = false;
            return resp;
        }
        resp.success = true;
        // We can't show the page directly, so
        // we show some generic page from the wallet.
        // TODO: this should not be webextensions-specific
        resp.backlink = chrome.extension.getURL("pages/reserve-success.html");
        return Query(db)
            .put("reserves", reserveRecord)
            .finish()
            .then(() => {
            // Do this in the background
            updateMintFromUrl(db, reserveRecord.mint_base_url)
                .then((mint) => updateReserve(db, reservePub, mint)
                .then((reserve) => depleteReserve(db, reserve, mint)));
            return resp;
        });
    })
        .then((resp) => {
        sendResponse(resp);
    });
    // Allow async response
    return true;
}
function copy(o) {
    return JSON.parse(JSON.stringify(o));
}
function rankDenom(denom1, denom2) {
    // Slow ... we should find a better way than to convert it evert time.
    let v1 = new Amount(denom1.value);
    let v2 = new Amount(denom2.value);
    return (-1) * v1.cmp(v2);
}
function withdrawPrepare(db, denom, reserve) {
    let reservePriv = new EddsaPrivateKey();
    reservePriv.loadCrock(reserve.reserve_priv);
    let reservePub = new EddsaPublicKey();
    reservePub.loadCrock(reserve.reserve_pub);
    let denomPub = RsaPublicKey.fromCrock(denom.denom_pub);
    let coinPriv = EddsaPrivateKey.create();
    let coinPub = coinPriv.getPublicKey();
    let blindingFactor = RsaBlindingKey.create(1024);
    let pubHash = coinPub.hash();
    let ev = rsaBlind(pubHash, blindingFactor, denomPub);
    if (!denom.fee_withdraw) {
        throw Error("Field fee_withdraw missing");
    }
    let amountWithFee = new Amount(denom.value);
    amountWithFee.add(new Amount(denom.fee_withdraw));
    let withdrawFee = new Amount(denom.fee_withdraw);
    // Signature
    let withdrawRequest = new 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 = eddsaSign(withdrawRequest.toPurpose(), reservePriv);
    let 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 Query(db).put("precoins", preCoin).finish().then(() => preCoin);
}
function withdrawExecute(db, pc) {
    return Query(db)
        .get("reserves", pc.reservePub)
        .then((r) => {
        let wd = {};
        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 httpPostJson(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 = rsaUnblind(RsaSignature.fromCrock(r.ev_sig), RsaBlindingKey.fromCrock(pc.blindingKey), RsaPublicKey.fromCrock(pc.denomPub));
        let coin = {
            coinPub: pc.coinPub,
            coinPriv: pc.coinPriv,
            denomPub: pc.denomPub,
            denomSig: denomSig.encode().toCrock(),
            currentAmount: pc.coinValue,
            mintBaseUrl: pc.mintBaseUrl,
        };
        return coin;
    });
}
function updateBadge(db) {
    function countNonEmpty(c, n) {
        if (c.currentAmount.fraction != 0 || c.currentAmount.value != 0) {
            return n + 1;
        }
        return n;
    }
    function doBadge(n) {
        chrome.browserAction.setBadgeText({ text: "" + n });
        chrome.browserAction.setBadgeBackgroundColor({ color: "#0F0" });
    }
    Query(db)
        .iter("coins")
        .reduce(countNonEmpty, 0)
        .then(doBadge);
}
function storeCoin(db, coin) {
    Query(db)
        .delete("precoins", coin.coinPub)
        .add("coins", coin)
        .finish()
        .then(() => {
        updateBadge(db);
    });
}
function withdraw(db, denom, reserve) {
    return withdrawPrepare(db, denom, reserve)
        .then((pc) => withdrawExecute(db, pc))
        .then((c) => storeCoin(db, c));
}
/**
 * Withdraw coins from a reserve until it is empty.
 */
function depleteReserve(db, reserve, mint) {
    let denoms = copy(mint.keys.denoms);
    let remaining = new Amount(reserve.current_amount);
    denoms.sort(rankDenom);
    let workList = [];
    for (let i = 0; i < 1000; i++) {
        let found = false;
        for (let d of denoms) {
            let cost = new Amount(d.value);
            cost.add(new Amount(d.fee_withdraw));
            if (remaining.cmp(cost) < 0) {
                continue;
            }
            found = true;
            remaining.sub(cost);
            workList.push(d);
        }
        if (!found) {
            console.log("did not find coins for remaining ", remaining.toJson());
            break;
        }
    }
    // Do the request one by one.
    function next() {
        if (workList.length == 0) {
            return;
        }
        let d = workList.pop();
        withdraw(db, d, reserve)
            .then(() => next());
    }
    next();
}
function updateReserve(db, reservePub, mint) {
    let reservePubStr = reservePub.toCrock();
    return Query(db)
        .get("reserves", reservePubStr)
        .then((reserve) => {
        let reqUrl = URI("reserve/status").absoluteTo(mint.baseUrl);
        reqUrl.query({ 'reserve_pub': reservePubStr });
        return httpGet(reqUrl).then(resp => {
            if (resp.status != 200) {
                throw Error();
            }
            let reserveInfo = JSON.parse(resp.responseText);
            if (!reserveInfo) {
                throw Error();
            }
            reserve.current_amount = reserveInfo.balance;
            return Query(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.
 */
function updateMintFromUrl(db, baseUrl) {
    let reqUrl = URI("keys").absoluteTo(baseUrl);
    return httpGet(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 = {
            baseUrl: baseUrl,
            keys: mintKeysJson
        };
        return Query(db).put("mints", mint).finish().then(() => mint);
    });
}
function getBalances(db) {
    function collectBalances(c, byCurrency) {
        let acc = byCurrency[c.currentAmount.currency];
        if (!acc) {
            acc = Amount.getZero(c.currentAmount.currency).toJson();
        }
        let am = new Amount(c.currentAmount);
        am.add(new Amount(acc));
        byCurrency[c.currentAmount.currency] = am.toJson();
        return byCurrency;
    }
    return Query(db)
        .iter("coins")
        .reduce(collectBalances, {});
}