-
Notifications
You must be signed in to change notification settings - Fork 0
/
Tcp.js
372 lines (314 loc) · 9.67 KB
/
Tcp.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
var net = require('net');
var bitcoin = require('bitcoinjs-lib');
var sha256 = bitcoin.crypto.sha256;
var debug = function(msg) {
//console.log(msg);
}
var uint8 = function(val) {
var v = Buffer.alloc(1);
v.writeUInt8(val);
return v;
}
var uint16 = function(val) {
var v = Buffer.alloc(2);
v.writeUInt16LE(val);
return v;
}
var uint32 = function(val) {
var v = Buffer.alloc(4);
v.writeUInt32LE(val);
return v;
}
var uint32be = function(val) {
var v = Buffer.alloc(4);
v.writeUInt32BE(val);
return v;
}
var uint64 = function(val) {
if(val > Number.MAX_SAFE_INTEGER) {
throw 'Error: out of range';
}
var v = Buffer.alloc(8);
v.writeInt32LE(val & -1, 0);
v.writeUInt32LE(Math.floor(val / 0x100000000), 4);
return v;
}
var hex = function(val) {
return Buffer.from(val, 'hex');
}
var str = function(val) {
return Buffer.from(val, 'ascii');
}
var pad = function(len) {
var v = Buffer.alloc(len);
v.fill(0);
return v;
}
var var_int = function(val) {
if (val < 0xfd) {
return uint8(val);
} else if (val <= 0xffff) {
return Buffer.concat([uint8(0xfd), uint16(val)]);
} else if (val <= 0xffffffff) {
return Buffer.concat([uint8(0xfe), uint32(val)]);
} else {
return Buffer.concat([uint8(0xff), uint64(val)]);
}
}
var var_str = function(val) {
return Buffer.concat([var_int(val.length), str(val)]);
}
var command = function(val) {
return Buffer.concat([str(val), pad(12 - val.length)]);
}
var inventory_type = {
ERROR: 0,
MSG_TX: 1,
MSG_BLOCK: 2,
MSG_FILTERED_BLOCK: 3,
MSG_CMPCT_BLOCK: 4
};
function Reader(buf) {
this.pos = 0;
this.buf = buf;
}
Reader.prototype.var_int = function() {
var val = this.buf.readUInt8(this.pos);
this.pos++;
if(val == 0xfd) {
val = this.buf.readUInt16LE(this.pos);
this.pos += 2;
} else if(val == 0xfe) {
val = this.buf.readUInt32LE(this.pos);
this.pos += 4;
} else if(val == 0xff) {
val = this.buf.readUInt32LE(this.pos + 4) * 0x100000000 + this.buf.readUInt32LE(this.pos);
this.pos += 8;
if(val > Number.MAX_SAFE_INTEGER) {
throw 'Error: out of range';
}
}
return val;
}
Reader.prototype.uint8 = function() {
var val = this.buf.readUInt8(this.pos);
this.pos += 1;
return val;
}
Reader.prototype.uint32 = function() {
var val = this.buf.readUInt32LE(this.pos);
this.pos += 4;
return val;
}
Reader.prototype.hash = function() {
var hash = this.buf.slice(this.pos, this.pos + 32);
this.pos += 32;
return hash;
}
Reader.prototype.var_str = function() {
var length = this.var_int();
var str = this.buf.slice(this.pos, this.pos + length);
this.pos += length;
return str.toString();
}
function Tcp(opts) {
var self = this;
var PROTOCOL_VERSION = opts.tcp.protocol_version;
var msg_version = Buffer.concat([
uint32(PROTOCOL_VERSION),
uint64(0xd),
uint64(Math.round(new Date().getTime() / 1000)),
pad(26),
pad(26),
uint64(0xa5a5),
var_str('/blockstor:0.1.0/'),
uint32(0)
]);
var message = function(cmd, payload) {
var checksum = sha256(sha256(payload));
return Buffer.concat([
uint32be(opts.tcp.start_string),
command(cmd),
uint32(payload.length),
checksum.slice(0, 4),
payload
]);
}
var req_threshold = 50;
var getdata_limit = 50;
var getblock_check_wait = 10;
var getblock_timeout = 5000;
var getblock_retry_limit = Math.round(getblock_timeout / getblock_check_wait);
var hashes = [];
var req_hashes = [];
var req_count = 0;
var prev_hash = null;
var height = 0;
var block_queue = [];
var aborting = false;
var status = {};
function send_message(data) {
if(!aborting) {
client.write(data);
}
}
function send_getblocks() {
send_message(message('getblocks', Buffer.concat([
uint32(PROTOCOL_VERSION),
var_int(1),
prev_hash ? prev_hash : pad(32),
pad(32)
])));
}
function check_getdata() {
if(req_count <= req_threshold) {
var getdata_count = 0;
var hash = hashes.shift();
if(hash) {
var inventories = Buffer.alloc(0);
do {
inventories = Buffer.concat([inventories, uint32(inventory_type.MSG_BLOCK), hash]);
req_hashes.push(hash);
req_count++;
getdata_count++;
if(getdata_limit && getdata_count >= getdata_limit) {
break;
}
hash = hashes.shift();
} while(hash);
send_message(message('getdata', Buffer.concat([var_int(getdata_count), inventories])));
}
}
}
function command_dispatch(header, body) {
switch(header.command) {
case 'version':
status['version'] = 1;
send_message(message('verack', Buffer.alloc(0)));
break;
case 'verack':
debug('recv: varack');
send_getblocks();
break;
case 'ping':
send_message(message('pong', body));
break;
case 'pong':
debug('recv: pong ' + body.toString('hex'));
break;
case 'inv':
var reader = new Reader(body);
var count = reader.var_int();
debug('recv: inv count=' + count);
for(var i = 0; i < count; i++) {
var type = reader.uint32();
var inv_hash = reader.hash();
if(type == inventory_type.MSG_BLOCK) {
hashes.push(inv_hash);
}
}
break;
case 'block':
var block = bitcoin.Block.fromBuffer(body);
prev_hash = prev_hash || block.prevHash;
var hash = req_hashes.shift();
if(hash) {
if(Buffer.compare(prev_hash, block.prevHash) == 0) {
height++;
block_queue.push({height: height, hash: hash, block: block, rawblock: body});
prev_hash = hash;
} else {
debug('skip --- ' + Buffer.from(hash).reverse().toString('hex'));
req_count--;
}
} else {
throw 'request hash not found';
}
if(req_hashes.length == 0 && hashes.length == 0) {
send_getblocks();
}
break;
case 'reject':
var reader = new Reader(body);
var reject_message = reader.var_str();
var reject_ccode = reader.uint8();
var reject_reason = reader.var_str();
debug('recv: ' + header.command + ' message=' + reject_message + ' ccode=' + reject_ccode.toString(16) + ' reason=' + reject_reason);
break;
default:
debug('recv: ' + header.command + ' - unhandled');
break;
}
}
var msg_data = null;
function message_parser(data) {
msg_data = msg_data ? Buffer.concat([msg_data, data]) : data;
while(1) {
if(msg_data.length < 24) {
break;
}
var body_length = msg_data.readUInt32LE(16);
var msg_length = 24 + body_length;
if(msg_data.length < msg_length) {
break;
}
var msg_header = {
version: msg_data.readUInt32LE(0).toString(16),
command: msg_data.slice(4, 16).toString().replace(/\0/g, ''),
length: body_length,
checksum: msg_data.readUInt32LE(20).toString(16)
};
var msg_body = msg_data.slice(24, msg_length);
msg_data = msg_data.slice(msg_length);
command_dispatch(msg_header, msg_body);
}
}
var client;
this.start = function(last_height, last_hash) {
height = last_height || height;
prev_hash = last_hash;
client = new net.Socket();
client.on('error', function(err) {
console.log(err.toString());
});
client.connect(opts.tcp.port, opts.tcp.host, function() {
debug('connect');
status['connect'] = 1;
send_message(message('version', msg_version));
});
client.on('data', function(data) {
message_parser(data);
});
}
this.stop = function() {
aborting = true;
client.end();
}
this.getblock = function() {
return new Promise(function(resolve) {
var retry_count = 0;
function wait_block() {
blockdata = block_queue.shift();
if(blockdata) {
req_count--;
check_getdata();
return resolve(blockdata);
} else {
check_getdata();
retry_count++;
if(retry_count > getblock_retry_limit) {
if(!status['connect']) {
console.log('ERROR: Cannot connect.');
} else if(status['connect'] && !status['version']) {
console.log('ERROR: No response.');
}
return resolve(null);
}
}
setTimeout(wait_block, getblock_check_wait);
}
wait_block();
});
}
}
module.exports = Tcp;