wallet-core/packages/taler-util/src/segwit_addr.ts

91 lines
3.0 KiB
TypeScript

// Copyright (c) 2017, 2021 Pieter Wuille
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
import bech32 from "./bech32.js"
export default {
encode: encode,
decode: decode
};
function convertbits(data: any, frombits: number, tobits: number, pad: boolean): any[] {
var acc = 0;
var bits = 0;
var ret = [];
var maxv = (1 << tobits) - 1;
for (var p = 0; p < data.length; ++p) {
var value = data[p];
if (value < 0 || (value >> frombits) !== 0) {
return []; //check this, was returning null
}
acc = (acc << frombits) | value;
bits += frombits;
while (bits >= tobits) {
bits -= tobits;
ret.push((acc >> bits) & maxv);
}
}
if (pad) {
if (bits > 0) {
ret.push((acc << (tobits - bits)) & maxv);
}
} else if (bits >= frombits || ((acc << (tobits - bits)) & maxv)) {
return []; //check this, was returning null
}
return ret;
}
function decode(hrp: any, addr: string) {
var bech32m = false;
var dec = bech32.decode(addr, bech32.encodings.BECH32);
if (dec === null) {
dec = bech32.decode(addr, bech32.encodings.BECH32M);
bech32m = true;
}
if (dec === null || dec.hrp !== hrp || dec.data.length < 1 || dec.data[0] > 16) {
return null;
}
var res = convertbits(dec.data.slice(1), 5, 8, false);
if (res === null || res.length < 2 || res.length > 40) {
return null;
}
if (dec.data[0] === 0 && res.length !== 20 && res.length !== 32) {
return null;
}
if (dec.data[0] === 0 && bech32m) {
return null;
}
if (dec.data[0] !== 0 && !bech32m) {
return null;
}
return { version: dec.data[0], program: res };
}
function encode(hrp: any, version: number, program: any): string {
var enc = bech32.encodings.BECH32;
if (version > 0) {
enc = bech32.encodings.BECH32M;
}
var ret = bech32.encode(hrp, [version].concat(convertbits(program, 8, 5, true)), enc);
if (decode(hrp, ret/*, enc*/) === null) {
return ""; //check this was returning null
}
return ret;
}