Add files via upload

2019-12-12 23:15:49 +00:00
parent 9617c25d37
commit 11323cc710
30 changed files with 40072 additions and 0 deletions
@@ -0,0 +1,236 @@
+//TODO - A reader MUST check that the signature is valid (see the n tagged field)
+//TODO - Tagged part of type f: the fallback on-chain address should be decoded into an address format
+//TODO - A reader MUST check that the SHA-2 256 in the h field exactly matches the hashed description.
+//TODO - A reader MUST use the n field to validate the signature instead of performing signature recovery if a valid n field is provided.
+
+function decode(paymentRequest) {
+    let input = paymentRequest.toLowerCase();
+    let splitPosition = input.lastIndexOf('1');
+    let humanReadablePart = input.substring(0, splitPosition);
+    let data = input.substring(splitPosition + 1, input.length - 6);
+    let checksum = input.substring(input.length - 6, input.length);
+    if (!verify_checksum(humanReadablePart, bech32ToFiveBitArray(data + checksum))) {
+        throw 'Malformed request: checksum is incorrect'; // A reader MUST fail if the checksum is incorrect.
+    }
+    return {
+        'human_readable_part': decodeHumanReadablePart(humanReadablePart),
+        'data': decodeData(data, humanReadablePart),
+        'checksum': checksum
+    }
+}
+
+function decodeHumanReadablePart(humanReadablePart) {
+    let prefixes = ['lnbc', 'lntb', 'lnbcrt', 'lnsb'];
+    let prefix;
+    prefixes.forEach(value => {
+        if (humanReadablePart.substring(0, value.length) === value) {
+            prefix = value;
+        }
+    });
+    if (prefix == null) throw 'Malformed request: unknown prefix'; // A reader MUST fail if it does not understand the prefix.
+    let amount = decodeAmount(humanReadablePart.substring(prefix.length, humanReadablePart.length));
+    return {
+        'prefix': prefix,
+        'amount': amount
+    }
+}
+
+function decodeData(data, humanReadablePart) {
+    let date32 = data.substring(0, 7);
+    let dateEpoch = bech32ToInt(date32);
+    let signature = data.substring(data.length - 104, data.length);
+    let tagData = data.substring(7, data.length - 104);
+    let decodedTags = decodeTags(tagData);
+    let value = bech32ToFiveBitArray(date32 + tagData);
+    value = fiveBitArrayTo8BitArray(value, true);
+    value = textToHexString(humanReadablePart).concat(byteArrayToHexString(value));
+    return {
+        'time_stamp': dateEpoch,
+        'tags': decodedTags,
+        'signature': decodeSignature(signature),
+        'signing_data': value
+    }
+}
+
+function decodeSignature(signature) {
+    let data = fiveBitArrayTo8BitArray(bech32ToFiveBitArray(signature));
+    let recoveryFlag = data[data.length - 1];
+    let r = byteArrayToHexString(data.slice(0, 32));
+    let s = byteArrayToHexString(data.slice(32, data.length - 1));
+    return {
+        'r': r,
+        's': s,
+        'recovery_flag': recoveryFlag
+    }
+}
+
+function decodeAmount(str) {
+    let multiplier = str.charAt(str.length - 1);
+    let amount = str.substring(0, str.length - 1);
+    if (amount.substring(0, 1) === '0') {
+        throw 'Malformed request: amount cannot contain leading zeros';
+    }
+    amount = Number(amount);
+    if (amount < 0 || !Number.isInteger(amount)) {
+        throw 'Malformed request: amount must be a positive decimal integer'; // A reader SHOULD fail if amount contains a non-digit
+    }
+
+    switch (multiplier) {
+        case '':
+            return 'Any amount'; // A reader SHOULD indicate if amount is unspecified
+        case 'p':
+            return amount / 10;
+        case 'n':
+            return amount * 100;
+        case 'u':
+            return amount * 100000;
+        case 'm':
+            return amount * 100000000;
+        default:
+            // A reader SHOULD fail if amount is followed by anything except a defined multiplier.
+            throw 'Malformed request: undefined amount multiplier';
+    }
+}
+
+function decodeTags(tagData) {
+    let tags = extractTags(tagData);
+    let decodedTags = [];
+    tags.forEach(value => decodedTags.push(decodeTag(value.type, value.length, value.data)));
+    return decodedTags;
+}
+
+function extractTags(str) {
+    let tags = [];
+    while (str.length > 0) {
+        let type = str.charAt(0);
+        let dataLength = bech32ToInt(str.substring(1, 3));
+        let data = str.substring(3, dataLength + 3);
+        tags.push({
+            'type': type,
+            'length': dataLength,
+            'data': data
+        });
+        str = str.substring(3 + dataLength, str.length);
+    }
+    return tags;
+}
+
+function decodeTag(type, length, data) {
+    switch (type) {
+        case 'p':
+            if (length !== 52) break; // A reader MUST skip over a 'p' field that does not have data_length 52
+            return {
+                'type': type,
+                'length': length,
+                'description': 'payment_hash',
+                'value': byteArrayToHexString(fiveBitArrayTo8BitArray(bech32ToFiveBitArray(data)))
+            };
+        case 'd':
+            return {
+                'type': type,
+                'length': length,
+                'description': 'description',
+                'value': bech32ToUTF8String(data)
+            };
+        case 'n':
+            if (length !== 53) break; // A reader MUST skip over a 'n' field that does not have data_length 53
+            return {
+                'type': type,
+                'length': length,
+                'description': 'payee_public_key',
+                'value': byteArrayToHexString(fiveBitArrayTo8BitArray(bech32ToFiveBitArray(data)))
+            };
+        case 'h':
+            if (length !== 52) break; // A reader MUST skip over a 'h' field that does not have data_length 52
+            return {
+                'type': type,
+                'length': length,
+                'description': 'description_hash',
+                'value': data
+            };
+        case 'x':
+            return {
+                'type': type,
+                'length': length,
+                'description': 'expiry',
+                'value': bech32ToInt(data)
+            };
+        case 'c':
+            return {
+                'type': type,
+                'length': length,
+                'description': 'min_final_cltv_expiry',
+                'value': bech32ToInt(data)
+            };
+        case 'f':
+            let version = bech32ToFiveBitArray(data.charAt(0))[0];
+            if (version < 0 || version > 18) break; // a reader MUST skip over an f field with unknown version.
+            data = data.substring(1, data.length);
+            return {
+                'type': type,
+                'length': length,
+                'description': 'fallback_address',
+                'value': {
+                    'version': version,
+                    'fallback_address': data
+                }
+            };
+        case 'r':
+            data = fiveBitArrayTo8BitArray(bech32ToFiveBitArray(data));
+            let pubkey = data.slice(0, 33);
+            let shortChannelId = data.slice(33, 41);
+            let feeBaseMsat = data.slice(41, 45);
+            let feeProportionalMillionths = data.slice(45, 49);
+            let cltvExpiryDelta = data.slice(49, 51);
+            return {
+                'type': type,
+                'length': length,
+                'description': 'routing_information',
+                'value': {
+                    'public_key': byteArrayToHexString(pubkey),
+                    'short_channel_id': byteArrayToHexString(shortChannelId),
+                    'fee_base_msat': byteArrayToInt(feeBaseMsat),
+                    'fee_proportional_millionths': byteArrayToInt(feeProportionalMillionths),
+                    'cltv_expiry_delta': byteArrayToInt(cltvExpiryDelta)
+                }
+            };
+        default:
+        // reader MUST skip over unknown fields
+    }
+}
+
+function polymod(values) {
+    let GEN = [0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3];
+    let chk = 1;
+    values.forEach((value) => {
+        let b = (chk >> 25);
+        chk = (chk & 0x1ffffff) << 5 ^ value;
+        for (let i = 0; i < 5; i++) {
+            if (((b >> i) & 1) === 1) {
+                chk ^= GEN[i];
+            } else {
+                chk ^= 0;
+            }
+        }
+    });
+    return chk;
+}
+
+function expand(str) {
+    let array = [];
+    for (let i = 0; i < str.length; i++) {
+        array.push(str.charCodeAt(i) >> 5);
+    }
+    array.push(0);
+    for (let i = 0; i < str.length; i++) {
+        array.push(str.charCodeAt(i) & 31);
+    }
+    return array;
+}
+
+function verify_checksum(hrp, data) {
+    hrp = expand(hrp);
+    let all = hrp.concat(data);
+    let bool = polymod(all);
+    return bool === 1;
+}
@@ -0,0 +1,96 @@
+const bech32CharValues = 'qpzry9x8gf2tvdw0s3jn54khce6mua7l';
+
+function byteArrayToInt(byteArray) {
+    let value = 0;
+    for (let i = 0; i < byteArray.length; ++i) {
+        value = (value << 8) + byteArray[i];
+    }
+    return value;
+}
+
+function bech32ToInt(str) {
+    let sum = 0;
+    for (let i = 0; i < str.length; i++) {
+        sum = sum * 32;
+        sum = sum + bech32CharValues.indexOf(str.charAt(i));
+    }
+    return sum;
+}
+
+function bech32ToFiveBitArray(str) {
+    let array = [];
+    for (let i = 0; i < str.length; i++) {
+        array.push(bech32CharValues.indexOf(str.charAt(i)));
+    }
+    return array;
+}
+
+function fiveBitArrayTo8BitArray(int5Array, includeOverflow) {
+    let count = 0;
+    let buffer = 0;
+    let byteArray = [];
+    int5Array.forEach((value) => {
+        buffer = (buffer << 5) + value;
+        count += 5;
+        if (count >= 8) {
+            byteArray.push(buffer >> (count - 8) & 255);
+            count -= 8;
+        }
+    });
+    if (includeOverflow && count > 0) {
+        byteArray.push(buffer << (8 - count) & 255);
+    }
+    return byteArray;
+}
+
+function bech32ToUTF8String(str) {
+    let int5Array = bech32ToFiveBitArray(str);
+    let byteArray = fiveBitArrayTo8BitArray(int5Array);
+
+    let utf8String = '';
+    for (let i = 0; i < byteArray.length; i++) {
+        utf8String += '%' + ('0' + byteArray[i].toString(16)).slice(-2);
+    }
+    return decodeURIComponent(utf8String);
+}
+
+function byteArrayToHexString(byteArray) {
+    return Array.prototype.map.call(byteArray, function (byte) {
+        return ('0' + (byte & 0xFF).toString(16)).slice(-2);
+    }).join('');
+}
+
+function textToHexString(text) {
+    let hexString = '';
+    for (let i = 0; i < text.length; i++) {
+        hexString += text.charCodeAt(i).toString(16);
+    }
+    return hexString;
+}
+
+function epochToDate(int) {
+    let date = new Date(int * 1000);
+    return date.toUTCString();
+}
+
+function isEmptyOrSpaces(str){
+    return str === null || str.match(/^ *$/) !== null;
+}
+
+function toFixed(x) {
+    if (Math.abs(x) < 1.0) {
+        var e = parseInt(x.toString().split('e-')[1]);
+        if (e) {
+            x *= Math.pow(10,e-1);
+            x = '0.' + (new Array(e)).join('0') + x.toString().substring(2);
+        }
+    } else {
+        var e = parseInt(x.toString().split('+')[1]);
+        if (e > 20) {
+            e -= 20;
+            x /= Math.pow(10,e);
+            x += (new Array(e+1)).join('0');
+        }
+    }
+    return x;
+}