15874541409

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/lib/protocol/consensus.js

/*!
 * consensus.js - consensus constants and helpers for hsd
 * Copyright (c) 2017-2018, Christopher Jeffrey (MIT License).
 * https://github.com/handshake-org/hsd
 */

'use strict';

/**
 * @module protocol/consensus
 */

const assert = require('bsert');
const BN = require('bcrypto/lib/bn.js');

/** @typedef {import('../types').Hash} Hash */
/** @typedef {import('../types').Amount} Amount */

/**
 * Coin exponent.
 * @const {Number}
 * @default
 */

exports.EXP = 6;

/**
 * One handshake in dollarydoos.
 * @const {Amount}
 * @default
 */

exports.COIN = Math.pow(10, exports.EXP);

/**
 * Maximum creators amount in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_CREATORS = 102e6 * exports.COIN;

/**
 * Maximum sponsors amount in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_SPONSORS = 102e6 * exports.COIN;

/**
 * Maximum TLD holder amount in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_TLD = 51e6 * exports.COIN;

/**
 * Maximum domain holder amount in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_DOMAIN = 51e6 * exports.COIN;

/**
 * Maximum CA/naming amount in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_CA_NAMING = 102e6 * exports.COIN;

/**
 * Maximum airdrop amount in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_AIRDROP = 0.952e9 * exports.COIN;

/**
 * Maximum initial supply in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_INITIAL = 1.36e9 * exports.COIN;

assert(exports.MAX_CREATORS
     + exports.MAX_SPONSORS
     + exports.MAX_TLD
     + exports.MAX_DOMAIN
     + exports.MAX_CA_NAMING
     + exports.MAX_AIRDROP === exports.MAX_INITIAL);

/**
 * Maximum amount of subsidies in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_SUBSIDY = 0.68e9 * exports.COIN;

assert(exports.MAX_INITIAL / 2 === exports.MAX_SUBSIDY);

/**
 * Maximum amount of money in dollarydoos (consensus).
 * @const {Amount}
 * @default
 */

exports.MAX_MONEY = 2.04e9 * exports.COIN;

assert(exports.MAX_INITIAL + exports.MAX_SUBSIDY === exports.MAX_MONEY);

/**
 * Base block subsidy (consensus).
 * @const {Amount}
 * @default
 */

exports.BASE_REWARD = 2000 * exports.COIN;

assert(2 * exports.BASE_REWARD * 170000 === exports.MAX_SUBSIDY);

/**
 * Block subsidy specifically for the genesis block.
 *
 * Explanation:
 * The max miner subsidy is 680000000, but due
 * to the halving interval it actually ends up
 * as 679999995.79, so add 2.21 coins to the
 * genesis reward output to make MAX_MONEY a
 * thoroughly true value.
 *
 * This, combined with the 3 1/4 year halving
 * interval, causes the supply to run dry
 * after about 100 years (around the year 2119,
 * or height=5,270,000).
 *
 * @const {Amount}
 * @default
 */

exports.GENESIS_REWARD = exports.BASE_REWARD + ((2.21 * exports.COIN) | 0);

/**
 * Genesis key.
 * @const {Buffer}
 */

exports.GENESIS_KEY =
  Buffer.from('f0237ae2e8f860f7d79124fc513f012e5aaa8d23', 'hex');

/**
 * Maximum block base size (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_BLOCK_SIZE = 1000000;

/**
 * Maximum block serialization size (protocol).
 * @const {Number}
 * @default
 */

exports.MAX_RAW_BLOCK_SIZE = 4000000;

/**
 * Maximum block weight (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_BLOCK_WEIGHT = 4000000;

/**
 * Maximum block sigops cost (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_BLOCK_SIGOPS = 80000;

/**
 * Maximum block tree opens.
 * @const {Number}
 * @default
 */

exports.MAX_BLOCK_OPENS = 300;

/**
 * Maximum block tree updates.
 * @const {Number}
 * @default
 */

exports.MAX_BLOCK_UPDATES = 600;

/**
 * Maximum block tree renewals.
 * @const {Number}
 * @default
 */

exports.MAX_BLOCK_RENEWALS = 600;

/**
 * Size of set to pick median time from.
 * @const {Number}
 * @default
 */

exports.MEDIAN_TIMESPAN = 11;

/**
 * Amount to multiply base/non-witness sizes by.
 * @const {Number}
 * @default
 */

exports.WITNESS_SCALE_FACTOR = 4;

/**
 * Maximum TX base size (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_TX_SIZE = 1000000;

/**
 * Maximum TX weight (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_TX_WEIGHT = 4000000;

/**
 * Locktime flag.
 * @const {Number}
 * @default
 */

exports.LOCKTIME_FLAG = (1 << 31) >>> 0;

/**
 * Locktime mask.
 * @const {Number}
 * @default
 */

exports.LOCKTIME_MASK = exports.LOCKTIME_FLAG - 1;

/**
 * Locktime granularity.
 * @const {Number}
 * @default
 */

exports.LOCKTIME_GRANULARITY = 9;

/**
 * Locktime multiplier.
 * @const {Number}
 * @default
 */

exports.LOCKTIME_MULT = 2 ** exports.LOCKTIME_GRANULARITY;

/**
 * Highest nSequence bit -- disables
 * sequence locktimes (consensus).
 * @const {Number}
 */

exports.SEQUENCE_DISABLE_FLAG = (1 << 31) >>> 0;

/**
 * Sequence time: height or time (consensus).
 * @const {Number}
 * @default
 */

exports.SEQUENCE_TYPE_FLAG = 1 << 22;

/**
 * Sequence granularity for time (consensus).
 * @const {Number}
 * @default
 */

exports.SEQUENCE_GRANULARITY = 9;

/**
 * Sequence mask (consensus).
 * @const {Number}
 * @default
 */

exports.SEQUENCE_MASK = 0x0000ffff;

/**
 * Max serialized script size (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_SCRIPT_SIZE = 10000;

/**
 * Max stack size during execution (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_SCRIPT_STACK = 1000;

/**
 * Max script element size (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_SCRIPT_PUSH = 520;

/**
 * Max opcodes executed (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_SCRIPT_OPS = 201;

/**
 * Max `n` value for multisig (consensus).
 * @const {Number}
 * @default
 */

exports.MAX_MULTISIG_PUBKEYS = 20;

/**
 * A hash of all zeroes.
 * @const {Buffer}
 * @default
 */

exports.ZERO_HASH = Buffer.alloc(32, 0x00);

/**
 * Block header size.
 * @const {Number}
 * @default
 */

exports.HEADER_SIZE = 236;

/**
 * Block header nonce size.
 * @const {Number}
 * @default
 */

exports.NONCE_SIZE = 24;

/**
 * Block header of all zeroes.
 * @const {Buffer}
 * @default
 */

exports.ZERO_HEADER = Buffer.alloc(exports.HEADER_SIZE, 0x00);

/**
 * Block header nonce of all zeroes.
 * @const {Buffer}
 * @default
 */

exports.ZERO_NONCE = Buffer.alloc(exports.NONCE_SIZE, 0x00);

/**
 * Convert a compact number to a big number.
 * Used for `block.bits` -> `target` conversion.
 * @param {Number} compact
 * @returns {BN}
 */

exports.fromCompact = function fromCompact(compact) {
  if (compact === 0)
    return new BN(0);

  const exponent = compact >>> 24;
  const negative = (compact >>> 23) & 1;

  let mantissa = compact & 0x7fffff;
  let num;

  if (exponent <= 3) {
    mantissa >>>= 8 * (3 - exponent);
    num = new BN(mantissa);
  } else {
    num = new BN(mantissa);
    num.iushln(8 * (exponent - 3));
  }

  if (negative)
    num.ineg();

  return num;
};

/**
 * Convert a big number to a compact number.
 * Used for `target` -> `block.bits` conversion.
 * @param {BN} num
 * @returns {Number}
 */

exports.toCompact = function toCompact(num) {
  if (num.isZero())
    return 0;

  let exponent = num.byteLength();
  let mantissa;

  if (exponent <= 3) {
    mantissa = num.toNumber();
    mantissa <<= 8 * (3 - exponent);
  } else {
    mantissa = num.ushrn(8 * (exponent - 3)).toNumber();
  }

  if (mantissa & 0x800000) {
    mantissa >>>= 8;
    exponent += 1;
  }

  let compact = (exponent << 24) | mantissa;

  if (num.isNeg())
    compact |= 0x800000;

  compact >>>= 0;

  return compact;
};

/**
 * Verify proof-of-work.
 * @param {Hash} hash
 * @param {Number} bits
 * @returns {Boolean}
 */

exports.verifyPOW = function verifyPOW(hash, bits) {
  const target = exports.fromCompact(bits);

  if (target.isNeg() || target.isZero())
    return false;

  if (target.bitLength() > 256)
    return false;

  const num = new BN(hash, 'be');

  if (num.gt(target))
    return false;

  return true;
};

/**
 * Calculate block subsidy.
 * @param {Number} height - Reward era by height.
 * @param {Number} interval - halving interval.
 * @returns {Amount}
 */

exports.getReward = function getReward(height, interval) {
  assert((height >>> 0) === height, 'Bad height for reward.');
  assert((interval >>> 0) === interval);

  const halvings = Math.floor(height / interval);

  if (halvings >= 52)
    return 0;

  return Math.floor(exports.BASE_REWARD / Math.pow(2, halvings));
};

/**
 * Test version bit.
 * @param {Number} version
 * @param {Number} bit
 * @returns {Boolean}
 */

exports.hasBit = function hasBit(version, bit) {
  return (version & (1 << bit)) !== 0;
};

1	/*!
2	* consensus.js - consensus constants and helpers for hsd
3	* Copyright (c) 2017-2018, Christopher Jeffrey (MIT License).
4	* https://github.com/handshake-org/hsd
5	*/
6
7	'use strict';
8
9	/**
10	* @module protocol/consensus
11	*/
12
13	const assert = require('bsert');	68✔
14	const BN = require('bcrypto/lib/bn.js');	68✔
15
16	/** @typedef {import('../types').Hash} Hash */
17	/** @typedef {import('../types').Amount} Amount */
18
19	/**
20	* Coin exponent.
21	* @const {Number}
22	* @default
23	*/
24
25	exports.EXP = 6;	68✔
26
27	/**
28	* One handshake in dollarydoos.
29	* @const {Amount}
30	* @default
31	*/
32
33	exports.COIN = Math.pow(10, exports.EXP);	68✔
34
35	/**
36	* Maximum creators amount in dollarydoos (consensus).
37	* @const {Amount}
38	* @default
39	*/
40
41	exports.MAX_CREATORS = 102e6 * exports.COIN;	68✔
42
43	/**
44	* Maximum sponsors amount in dollarydoos (consensus).
45	* @const {Amount}
46	* @default
47	*/
48
49	exports.MAX_SPONSORS = 102e6 * exports.COIN;	68✔
50
51	/**
52	* Maximum TLD holder amount in dollarydoos (consensus).
53	* @const {Amount}
54	* @default
55	*/
56
57	exports.MAX_TLD = 51e6 * exports.COIN;	68✔
58
59	/**
60	* Maximum domain holder amount in dollarydoos (consensus).
61	* @const {Amount}
62	* @default
63	*/
64
65	exports.MAX_DOMAIN = 51e6 * exports.COIN;	68✔
66
67	/**
68	* Maximum CA/naming amount in dollarydoos (consensus).
69	* @const {Amount}
70	* @default
71	*/
72
73	exports.MAX_CA_NAMING = 102e6 * exports.COIN;	68✔
74
75	/**
76	* Maximum airdrop amount in dollarydoos (consensus).
77	* @const {Amount}
78	* @default
79	*/
80
81	exports.MAX_AIRDROP = 0.952e9 * exports.COIN;	68✔
82
83	/**
84	* Maximum initial supply in dollarydoos (consensus).
85	* @const {Amount}
86	* @default
87	*/
88
89	exports.MAX_INITIAL = 1.36e9 * exports.COIN;	68✔
90
91	assert(exports.MAX_CREATORS	68✔
92	+ exports.MAX_SPONSORS
93	+ exports.MAX_TLD
94	+ exports.MAX_DOMAIN
95	+ exports.MAX_CA_NAMING
96	+ exports.MAX_AIRDROP === exports.MAX_INITIAL);
97
98	/**
99	* Maximum amount of subsidies in dollarydoos (consensus).
100	* @const {Amount}
101	* @default
102	*/
103
104	exports.MAX_SUBSIDY = 0.68e9 * exports.COIN;	68✔
105
106	assert(exports.MAX_INITIAL / 2 === exports.MAX_SUBSIDY);	68✔
107
108	/**
109	* Maximum amount of money in dollarydoos (consensus).
110	* @const {Amount}
111	* @default
112	*/
113
114	exports.MAX_MONEY = 2.04e9 * exports.COIN;	68✔
115
116	assert(exports.MAX_INITIAL + exports.MAX_SUBSIDY === exports.MAX_MONEY);	68✔
117
118	/**
119	* Base block subsidy (consensus).
120	* @const {Amount}
121	* @default
122	*/
123
124	exports.BASE_REWARD = 2000 * exports.COIN;	68✔
125
126	assert(2 * exports.BASE_REWARD * 170000 === exports.MAX_SUBSIDY);	68✔
127
128	/**
129	* Block subsidy specifically for the genesis block.
130	*
131	* Explanation:
132	* The max miner subsidy is 680000000, but due
133	* to the halving interval it actually ends up
134	* as 679999995.79, so add 2.21 coins to the
135	* genesis reward output to make MAX_MONEY a
136	* thoroughly true value.
137	*
138	* This, combined with the 3 1/4 year halving
139	* interval, causes the supply to run dry
140	* after about 100 years (around the year 2119,
141	* or height=5,270,000).
142	*
143	* @const {Amount}
144	* @default
145	*/
146
147	exports.GENESIS_REWARD = exports.BASE_REWARD + ((2.21 * exports.COIN) \| 0);	68✔
148
149	/**
150	* Genesis key.
151	* @const {Buffer}
152	*/
153
154	exports.GENESIS_KEY =	68✔
155	Buffer.from('f0237ae2e8f860f7d79124fc513f012e5aaa8d23', 'hex');
156
157	/**
158	* Maximum block base size (consensus).
159	* @const {Number}
160	* @default
161	*/
162
163	exports.MAX_BLOCK_SIZE = 1000000;	68✔
164
165	/**
166	* Maximum block serialization size (protocol).
167	* @const {Number}
168	* @default
169	*/
170
171	exports.MAX_RAW_BLOCK_SIZE = 4000000;	68✔
172
173	/**
174	* Maximum block weight (consensus).
175	* @const {Number}
176	* @default
177	*/
178
179	exports.MAX_BLOCK_WEIGHT = 4000000;	68✔
180
181	/**
182	* Maximum block sigops cost (consensus).
183	* @const {Number}
184	* @default
185	*/
186
187	exports.MAX_BLOCK_SIGOPS = 80000;	68✔
188
189	/**
190	* Maximum block tree opens.
191	* @const {Number}
192	* @default
193	*/
194
195	exports.MAX_BLOCK_OPENS = 300;	68✔
196
197	/**
198	* Maximum block tree updates.
199	* @const {Number}
200	* @default
201	*/
202
203	exports.MAX_BLOCK_UPDATES = 600;	68✔
204
205	/**
206	* Maximum block tree renewals.
207	* @const {Number}
208	* @default
209	*/
210
211	exports.MAX_BLOCK_RENEWALS = 600;	68✔
212
213	/**
214	* Size of set to pick median time from.
215	* @const {Number}
216	* @default
217	*/
218
219	exports.MEDIAN_TIMESPAN = 11;	68✔
220
221	/**
222	* Amount to multiply base/non-witness sizes by.
223	* @const {Number}
224	* @default
225	*/
226
227	exports.WITNESS_SCALE_FACTOR = 4;	68✔
228
229	/**
230	* Maximum TX base size (consensus).
231	* @const {Number}
232	* @default
233	*/
234
235	exports.MAX_TX_SIZE = 1000000;	68✔
236
237	/**
238	* Maximum TX weight (consensus).
239	* @const {Number}
240	* @default
241	*/
242
243	exports.MAX_TX_WEIGHT = 4000000;	68✔
244
245	/**
246	* Locktime flag.
247	* @const {Number}
248	* @default
249	*/
250
251	exports.LOCKTIME_FLAG = (1 << 31) >>> 0;	68✔
252
253	/**
254	* Locktime mask.
255	* @const {Number}
256	* @default
257	*/
258
259	exports.LOCKTIME_MASK = exports.LOCKTIME_FLAG - 1;	68✔
260
261	/**
262	* Locktime granularity.
263	* @const {Number}
264	* @default
265	*/
266
267	exports.LOCKTIME_GRANULARITY = 9;	68✔
268
269	/**
270	* Locktime multiplier.
271	* @const {Number}
272	* @default
273	*/
274
275	exports.LOCKTIME_MULT = 2 ** exports.LOCKTIME_GRANULARITY;	68✔
276
277	/**
278	* Highest nSequence bit -- disables
279	* sequence locktimes (consensus).
280	* @const {Number}
281	*/
282
283	exports.SEQUENCE_DISABLE_FLAG = (1 << 31) >>> 0;	68✔
284
285	/**
286	* Sequence time: height or time (consensus).
287	* @const {Number}
288	* @default
289	*/
290
291	exports.SEQUENCE_TYPE_FLAG = 1 << 22;	68✔
292
293	/**
294	* Sequence granularity for time (consensus).
295	* @const {Number}
296	* @default
297	*/
298
299	exports.SEQUENCE_GRANULARITY = 9;	68✔
300
301	/**
302	* Sequence mask (consensus).
303	* @const {Number}
304	* @default
305	*/
306
307	exports.SEQUENCE_MASK = 0x0000ffff;	68✔
308
309	/**
310	* Max serialized script size (consensus).
311	* @const {Number}
312	* @default
313	*/
314
315	exports.MAX_SCRIPT_SIZE = 10000;	68✔
316
317	/**
318	* Max stack size during execution (consensus).
319	* @const {Number}
320	* @default
321	*/
322
323	exports.MAX_SCRIPT_STACK = 1000;	68✔
324
325	/**
326	* Max script element size (consensus).
327	* @const {Number}
328	* @default
329	*/
330
331	exports.MAX_SCRIPT_PUSH = 520;	68✔
332
333	/**
334	* Max opcodes executed (consensus).
335	* @const {Number}
336	* @default
337	*/
338
339	exports.MAX_SCRIPT_OPS = 201;	68✔
340
341	/**
342	* Max `n` value for multisig (consensus).
343	* @const {Number}
344	* @default
345	*/
346
347	exports.MAX_MULTISIG_PUBKEYS = 20;	68✔
348
349	/**
350	* A hash of all zeroes.
351	* @const {Buffer}
352	* @default
353	*/
354
355	exports.ZERO_HASH = Buffer.alloc(32, 0x00);	68✔
356
357	/**
358	* Block header size.
359	* @const {Number}
360	* @default
361	*/
362
363	exports.HEADER_SIZE = 236;	68✔
364
365	/**
366	* Block header nonce size.
367	* @const {Number}
368	* @default
369	*/
370
371	exports.NONCE_SIZE = 24;	68✔
372
373	/**
374	* Block header of all zeroes.
375	* @const {Buffer}
376	* @default
377	*/
378
379	exports.ZERO_HEADER = Buffer.alloc(exports.HEADER_SIZE, 0x00);	68✔
380
381	/**
382	* Block header nonce of all zeroes.
383	* @const {Buffer}
384	* @default
385	*/
386
387	exports.ZERO_NONCE = Buffer.alloc(exports.NONCE_SIZE, 0x00);	68✔
388
389	/**
390	* Convert a compact number to a big number.
391	* Used for `block.bits` -> `target` conversion.
392	* @param {Number} compact
393	* @returns {BN}
394	*/
395
396	exports.fromCompact = function fromCompact(compact) {	68✔
397	if (compact === 0)	58,455!
398	return new BN(0);	×
399
400	const exponent = compact >>> 24;	58,455✔
401	const negative = (compact >>> 23) & 1;	58,455✔
402
403	let mantissa = compact & 0x7fffff;	58,455✔
404	let num;
405
406	if (exponent <= 3) {	58,455!
407	mantissa >>>= 8 * (3 - exponent);	×
408	num = new BN(mantissa);	×
409	} else {
410	num = new BN(mantissa);	58,455✔
411	num.iushln(8 * (exponent - 3));	58,455✔
412	}
413
414	if (negative)	58,455!
415	num.ineg();	×
416
417	return num;	58,455✔
418	};
419
420	/**
421	* Convert a big number to a compact number.
422	* Used for `target` -> `block.bits` conversion.
423	* @param {BN} num
424	* @returns {Number}
425	*/
426
427	exports.toCompact = function toCompact(num) {	68✔
428	if (num.isZero())	1!
429	return 0;	×
430
431	let exponent = num.byteLength();	1✔
432	let mantissa;
433
434	if (exponent <= 3) {	1!
435	mantissa = num.toNumber();	×
436	mantissa <<= 8 * (3 - exponent);	×
437	} else {
438	mantissa = num.ushrn(8 * (exponent - 3)).toNumber();	1✔
439	}
440
441	if (mantissa & 0x800000) {	1!
442	mantissa >>>= 8;	1✔
443	exponent += 1;	1✔
444	}
445
446	let compact = (exponent << 24) \| mantissa;	1✔
447
448	if (num.isNeg())	1!
449	compact \|= 0x800000;	×
450
451	compact >>>= 0;	1✔
452
453	return compact;	1✔
454	};
455
456	/**
457	* Verify proof-of-work.
458	* @param {Hash} hash
459	* @param {Number} bits
460	* @returns {Boolean}
461	*/
462
463	exports.verifyPOW = function verifyPOW(hash, bits) {	68✔
464	const target = exports.fromCompact(bits);	20,176✔
465
466	if (target.isNeg() \|\| target.isZero())	20,176!
467	return false;	×
468
469	if (target.bitLength() > 256)	20,176!
470	return false;	×
471
472	const num = new BN(hash, 'be');	20,176✔
473
474	if (num.gt(target))	20,176!
475	return false;	×
476
477	return true;	20,176✔
478	};
479
480	/**
481	* Calculate block subsidy.
482	* @param {Number} height - Reward era by height.
483	* @param {Number} interval - halving interval.
484	* @returns {Amount}
485	*/
486
487	exports.getReward = function getReward(height, interval) {	68✔
488	assert((height >>> 0) === height, 'Bad height for reward.');	5,330,001✔
489	assert((interval >>> 0) === interval);	5,330,001✔
490
491	const halvings = Math.floor(height / interval);	5,330,001✔
492
493	if (halvings >= 52)	5,330,001!
494	return 0;	×
495
496	return Math.floor(exports.BASE_REWARD / Math.pow(2, halvings));	5,330,001✔
497	};
498
499	/**
500	* Test version bit.
501	* @param {Number} version
502	* @param {Number} bit
503	* @returns {Boolean}
504	*/
505
506	exports.hasBit = function hasBit(version, bit) {	68✔
507	return (version & (1 << bit)) !== 0;	24,371✔
508	};

handshake-org / hsd / 15874541409

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