commit 091685a9e22b3c6b5f910355be90674f8478b9c1
Author: parazyd <parazyd@dyne.org>
Date: Fri, 19 Feb 2021 00:08:51 +0100
First commit.
Diffstat:
15 files changed, 1736 insertions(+), 0 deletions(-)
diff --git a/.gitignore b/.gitignore
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+*.pyc+
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diff --git a/LICENSE b/LICENSE
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+ GNU AFFERO GENERAL PUBLIC LICENSE
+ Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
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+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source. For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code. There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.
diff --git a/README.md b/README.md
@@ -0,0 +1,91 @@
+electrum-obelisk
+================
+
+
+
+A **work-in-progress** implementation of an Electrum server using
+[libbitcoin](https://libbitcoin.info) as a backend.
+
+TODO
+----
+
+* Better (and more) error handling
+* More testing
+* git grep -E "TODO:|BUG:"
+
+
+Usage
+-----
+
+Install `bx` and `bs`
+
+* https://github.com/libbitcoin/libbitcoin-explorer/
+* https://github.com/libbitcoin/libbitcoin-server/
+
+Configure them per your needs and sync the node. Following this,
+configure `config.ini` to use with obelisk.
+
+Now you can run `./obelisk config.ini` to start the server.
+
+Connect Electrum with:
+
+```
+electrum --oneserver --server 127.0.0.1:50002:s
+```
+
+Talk
+----
+
+`#libbitcoin` on freenode.
+
+
+License
+-------
+
+electrum-obelisk is licensed [AGPL-3](LICENSE.md).
+
+```
+electrum-obelisk
+Copyright (C) 2020-2021 Ivan J. <parazyd@dyne.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program 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 Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+```
+
+This software is heavily inspired by, and certain parts of the code
+are copied from Chris Belcher's implementation of
+[electrum-personal-server](https://github.com/chris-belcher/electrum-personal-server]
+and are copyrighted under the MIT license:
+
+```
+The MIT License (MIT)
+
+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.
+```
diff --git a/certs/cert.crt b/certs/cert.crt
@@ -0,0 +1,19 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/certs/cert.key b/certs/cert.key
@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----
diff --git a/config.ini b/config.ini
@@ -0,0 +1,27 @@
+# Configuration file for electrum-obelisk
+
+[electrum-obelisk]
+# 0.0.0.0 to bind to any IP, 127.0.0.1 to bind to localhost
+host = 127.0.0.1
+port = 50002
+
+# Which chain should electrum-obelisk be using (mainnet/regtest/testnet)
+chain = mainnet
+
+# Endpoints served by bs.
+bs_query = tcp://localhost:9091
+bs_heartbeat = tcp://localhost:9092
+bs_block = tcp://localhost:9093
+bs_transaction = tcp://localhost:9094
+
+# Space-separated whitelist of IP addresses
+# Accepts CIDR notation, e.g. 192.169.0.0/16 or 2a01:4f8:1f1::/120
+# Star (*) means all are accepted (Generally requires host to be 0.0.0.0)
+ip_whitelist = *
+
+# TLS certificate
+# Uses the default one, which is fine because by default nobody should be
+# allowed to connect to your server or scan your packets.
+# To generate another certificate use openssl.
+certfile = certs/cert.crt
+keyfile = certs/cert.key
diff --git a/electrumobelisk/__init__.py b/electrumobelisk/__init__.py
diff --git a/electrumobelisk/bx.py b/electrumobelisk/bx.py
@@ -0,0 +1,66 @@
+#!/usr/bin/env python3
+# electrum-obelisk
+# Copyright (C) 2020-2021 Ivan J. <parazyd@dyne.org>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+""" Module for interfacing with the bx/bs command """
+import sys
+from subprocess import run, CalledProcessError
+from logging import getLogger
+from json import loads
+from json.decoder import JSONDecodeError
+
+
+def bx_json(args):
+ """ Get JSON data using bx """
+ cmd = ['bx', args[0], '--format', 'json']
+ cmd.extend(args[1:])
+ try:
+ output = run(cmd, check=True, capture_output=True)
+ except CalledProcessError:
+ log = getLogger('electrum-obelisk')
+ log.warning('bx_json (%s) failed', cmd)
+ return None
+ try:
+ return loads(output.stdout)
+ except JSONDecodeError:
+ return None
+
+
+def bx_raw(args):
+ """ Get raw data using bx """
+ cmd = ['bx']
+ cmd.extend(args)
+ try:
+ output = run(cmd, check=True, capture_output=True)
+ except CalledProcessError:
+ log = getLogger('electrum-obelisk')
+ log.warning('bx_raw (%s) failed', cmd)
+ return None
+ if output.stdout:
+ return output.stdout[:-1]
+ return None
+
+
+def bs_version():
+ """ Get output of bs -v """
+ try:
+ output = run(['bs', '-v'], capture_output=True, check=False)
+ return output.stdout.decode()[:-1]
+ except FileNotFoundError:
+ log = getLogger('electrum-obelisk')
+ log.error('Error: bs is not installed.')
+ # TODO: Reenable this
+ #sys.exit(1)
+ return ""
diff --git a/electrumobelisk/hash.py b/electrumobelisk/hash.py
@@ -0,0 +1,39 @@
+#!/usr/bin/env python3
+# electrum-obelisk
+# Copyright (C) 2020-2021 Ivan J. <parazyd@dyne.org>
+# Copyright (C) 2016-2018 Neil Booth (MIT License)
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+""" Cryptographic hash functions and helpers """
+import hashlib
+
+
+_sha256 = hashlib.sha256
+
+
+def sha256(inp):
+ """ Simple wrapper of hashlib sha256. """
+ return _sha256(inp).digest()
+
+
+def double_sha256(inp):
+ """ sha256 of sha256, as used extensively in bitcoin """
+ return sha256(sha256(inp))
+
+
+def hash_to_hex_str(inp):
+ """ Convert a big-endian binary hash to displayed hex string.
+ Display form of a binary hash is reversed and converted to hex.
+ """
+ return bytes(reversed(inp)).hex()
diff --git a/electrumobelisk/helpers.py b/electrumobelisk/helpers.py
@@ -0,0 +1,74 @@
+#!/usr/bin/env python3
+# electrum-obelisk
+# Copyright (C) 2020-2021 Ivan J. <parazyd@dyne.org>
+# Copyright (c) 2018-2020 Chris Belcher (MIT License)
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+""" Useful helper functions """
+from binascii import hexlify
+
+code_strings = {
+ 2: '01',
+ 10: '0123456789',
+ 16: '0123456789abcdef',
+ 32: 'abcdefghijklmnopqrstuvwxyz234567',
+ 58: '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz',
+ 256: ''.join([chr(x) for x in range(256)]),
+}
+
+
+def get_code_string(base):
+ """ Get valid characters for base """
+ if base in code_strings:
+ return code_strings[base]
+ raise ValueError('Invalid base!')
+
+
+def encode(val, base, minlen=0):
+ """ Encoding for serialization """
+ base, minlen = int(base), int(minlen)
+ code_string = get_code_string(base)
+ result_bytes = bytes()
+ while val > 0:
+ curcode = code_string[val % base]
+ result_bytes = bytes([ord(curcode)]) + result_bytes
+ val //= base
+
+ pad_size = minlen - len(result_bytes)
+
+ padding_element = b'\x00' if base == 256 else b'1' \
+ if base == 58 else b'0'
+ if pad_size > 0:
+ result_bytes = padding_element * pad_size + result_bytes
+
+ result_string = ''.join([chr(y) for y in result_bytes])
+ result = result_bytes if base == 256 else result_string
+ return result
+
+
+def safe_hexlify(_str):
+ """ hexlify and return a string """
+ return str(hexlify(_str), 'utf-8')
+
+
+def num_to_var_int(num):
+ """ number to bytes """
+ num = int(num)
+ if num < 253:
+ return bytes([num])
+ if num < 65536:
+ return bytes([253]) + encode(num, 256, 2)[::-1]
+ if num < 4294967296:
+ return bytes([254]) + encode(num, 256, 4)[::-1]
+ return bytes([255]) + encode(num, 256, 8)[::-1]
diff --git a/electrumobelisk/merkle.py b/electrumobelisk/merkle.py
@@ -0,0 +1,80 @@
+#!/usr/bin/env python3
+# electrum-obelisk
+# Copyright (C) 2020-2021 Ivan J. <parazyd@dyne.org>
+# Copyright (C) 2018 Neil Booth (MIT License)
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+""" Merkle trees, branches, proofs and roots """
+from binascii import unhexlify
+from math import ceil, log
+
+from electrumobelisk.bx import bx_json
+from electrumobelisk.hash import double_sha256, hash_to_hex_str
+
+
+def branch_length(hash_count):
+ """ Return the length of a merkle branch given the number of hashes """
+ return ceil(log(hash_count, 2))
+
+
+def merkle_branch_and_root(hashes, index):
+ """ Return a (merkle branch, merkle_root) pair given hashes, and the
+ index of one of those hashes. """
+ hashes = list(hashes)
+ if not isinstance(index, int):
+ raise TypeError('index must be an integer')
+ # This also asserts hashes is not empty
+ if not 0 <= index < len(hashes):
+ raise ValueError('index out of range')
+ length = branch_length(len(hashes))
+
+ branch = []
+ for _ in range(length):
+ if len(hashes) & 1:
+ hashes.append(hashes[-1])
+ branch.append(hashes[index ^ 1])
+ index >>= 1
+ hashes = [double_sha256(hashes[n] + hashes[n+1])
+ for n in range(0, len(hashes), 2)]
+ return branch, hashes[0]
+
+def _merkle_branch(tx_hashes, tx_pos):
+ branch, _root = merkle_branch_and_root(tx_hashes, tx_pos)
+ branch = [hash_to_hex_str(hash) for hash in branch]
+ return branch
+
+def merkle_branch_for_tx_hash(height, tx_hash):
+ """ Return merkle branch and tx_position for given height/tx_hash """
+ metadata = bx_json(['fetch-tx-index', tx_hash])
+ if not metadata:
+ return None, None
+ tx_pos = int(metadata['metadata']['index'])
+ block = bx_json(['fetch-block', '--height', str(height)])
+ if not block:
+ return None, None
+ #tx_hashes = [i['hash'] for i in block['block']['transactions']]
+ tx_hashes = [unhexlify(i['hash'])[::-1]
+ for i in block['block']['transactions']]
+ return _merkle_branch(tx_hashes, tx_pos), tx_pos
+
+
+def merkle_branch_for_tx_pos(height, tx_pos):
+ """ Return merkle branch for given height/tx_pos """
+ block = bx_json(['fetch-block', '--height', str(height)])
+ if not block:
+ return None, None
+ txid = block['block']['transactions'][tx_pos]
+ tx_hashes = [reversed(unhexlify(i['hash']))
+ for i in block['block']['transactions']]
+ return _merkle_branch(tx_hashes, tx_pos), txid
diff --git a/electrumobelisk/protocol.py b/electrumobelisk/protocol.py
@@ -0,0 +1,340 @@
+#!/usr/bin/env python3
+# electrum-obelisk
+# Copyright (C) 2020-2021 Ivan J. <parazyd@dyne.org>
+# Copyright (C) 2018-2020 Chris Belcher (MIT License)
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+""" non-strict electrum protocol implementation """
+from struct import unpack
+from binascii import unhexlify
+from threading import Thread
+
+import zmq
+
+from electrumobelisk.bx import bx_json, bx_raw, bs_version
+from electrumobelisk.hash import sha256
+from electrumobelisk.helpers import safe_hexlify
+from electrumobelisk.merkle import (merkle_branch_for_tx_hash,
+ merkle_branch_for_tx_pos)
+from electrumobelisk.query import (q_fetch_header_by_height,
+ q_fetch_headers_by_height_count,
+ q_fetch_tx_by_txid)
+
+
+VERSION = '0.0'
+SERVER_PROTO_MIN = '1.4'
+SERVER_PROTO_MAX = '1.4.2'
+DONATION_ADDR = 'bc1q7an9p5pz6pjwjk4r48zke2yfaevafzpglg26mz'
+__certfile__ = 'certs/cert.crt'
+__keyfile__ = 'certs/cert.key'
+
+BANNER = """
+Welcome to electrum-obelisk
+
+"Tools for The People"
+%s
+electrum-obelisk version: %s
+
+electrum-obelisk is a server that uses libbitcoin-server as its backend.
+Source code can be found at: https://github.com/parazyd/electrum-obelisk
+
+Please consider donating: %s
+
+""" % (bs_version(), VERSION, DONATION_ADDR)
+
+
+def fetch_scripthash_history(scripthash):
+ """ Fetch transaction history for given scripthash and return a list """
+ # BUG: fetch-history sometimes returns duplicates, so below in the
+ # loop it is necessary to check if we have already added the element.
+ hist = []
+ data = bx_json(['fetch-history', scripthash])
+ for i in data['transfers']:
+ # print(data)
+ if 'received' in i:
+ entr = {'height': int(i['received']['height']),
+ 'tx_hash': i['received']['hash']}
+ if entr not in hist:
+ hist.append(entr)
+ if 'spent' in i:
+ entr = {'height': int(i['spent']['height']),
+ 'tx_hash': i['spent']['hash']}
+ if entr not in hist:
+ hist.append(entr)
+ return hist
+
+
+def electrum_scripthash_status(hist):
+ """ Encode scripthash status into the protocol format """
+ if len(hist) < 1:
+ return None
+ ret = ""
+ for i in hist:
+ ret += '%s:%d:' % (i['tx_hash'], i['height'])
+ return safe_hexlify(sha256(bytes(ret.encode('ascii'))))
+
+
+class ElectrumProtocol():
+ """
+ Class which implements the Electrum protocol for a single connection.
+ It does not handle the actual sockets, which could be any combination
+ if blocking/non-blocking, asyncio, twisted, etc.
+ This class may be instantized multiple times if the server accepts
+ multiple client connections at once.
+ """
+ def __init__(self, log, chain, endpoints):
+ self.log = log
+ self.send_reply_fun = None
+ self.version_called = False
+ self.subscribed_to_headers = False
+ self.subscribed_scripthash = {}
+ self.endpoints = endpoints
+
+ if chain == 'mainnet':
+ self.genesis = \
+ '000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f'
+ elif chain == 'regtest':
+ self.genesis = \
+ '0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206'
+ elif chain == 'testnet':
+ self.genesis = \
+ '000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943'
+ else:
+ raise ValueError('Invalid chain "%s"' % chain)
+
+ def _send_response(self, query, result):
+ response = {'jsonrpc': '2.0', 'result': result, 'id': query['id']}
+ self.send_reply_fun(response)
+
+ def _send_update(self, update):
+ update['jsonrpc'] = '2.0'
+ self.send_reply_fun(update)
+
+ def _send_error(self, nid, error):
+ payload = {'error': error, 'jsonrpc': '2.0', 'id': nid}
+ self.send_reply_fun(payload)
+
+ def set_send_reply_fun(self, send_reply_fun):
+ """ Function to set a reply function """
+ self.send_reply_fun = send_reply_fun
+
+ def on_disconnect(self):
+ """ Used to clean up when client is disconnected """
+ self.log.debug('on_disconnect')
+ self.subscribed_to_headers = False
+ self.version_called = False
+ self.subscribed_scripthash = {}
+
+ def _subscribe_to_blocks(self):
+ if not self.subscribed_to_headers:
+ context = zmq.Context()
+ socket = context.socket(zmq.SUB) # pylint: disable=E1101
+ socket.connect(self.endpoints['query'])
+ socket.setsockopt_string(zmq.SUBSCRIBE, '') # pylint: disable=E1101
+ socket.setsockopt(zmq.TCP_KEEPALIVE, 1) # pylint: disable=E1101
+ self.subscribed_to_headers = True
+ while self.subscribed_to_headers:
+ _ = unpack('<H', socket.recv())[0]
+ height = unpack('<I', socket.recv())[0]
+ block = socket.recv()
+ header = {'hex': safe_hexlify(block), 'height': int(height)}
+ update = {'method': 'blockchain.headers.subscribe',
+ 'params': header}
+ self._send_update(update)
+
+ def _subscribe_to_scripthash(self, scripthash):
+ # TODO: subscribe_to_scripthash()
+ # Append to hist list from self.subscribed_scripthash and send
+ # update notification/method.
+ return
+
+# https://electrumx-spesmilo.readthedocs.io/en/latest/protocol-methods.html
+ def handle_query(self, query):
+ """ Electrum protocol method handlers """
+ if 'method' not in query:
+ raise IOError('Bad client query, no "method"')
+ method = query['method']
+
+ if method == 'blockchain.block.header':
+ # TODO: cp_height
+ height = int(query['params'][0])
+ header = q_fetch_header_by_height(self.endpoints['query'], height)
+ if not header:
+ error = {'message': 'block at height %d not found' % height}
+ self._send_error(query['id'], error)
+ return
+ self._send_response(query, safe_hexlify(header))
+
+ elif method == 'blockchain.block.headers':
+ # TODO: cp_height
+ # Electrum doesn't allow max_chunk_size to be less than 2016.
+ # gopher://bitreich.org/9/memecache/convenience-store.mkv
+ max_chunk_size = 2016
+ start_height = query['params'][0]
+ count = int(query['params'][1])
+ count = min(count, max_chunk_size)
+ headers = q_fetch_headers_by_height_count(self.endpoints['query'],
+ start_height, count)
+ self._send_response(query, {'hex': safe_hexlify(headers),
+ 'count': len(headers)//80,
+ 'max': max_chunk_size})
+
+ elif method == 'blockchain.estimatefee':
+ self._send_response(query, -1)
+
+ elif method == 'blockchain.headers.subscribe':
+ if not self.subscribed_to_headers:
+ Thread(target=self._subscribe_to_blocks).start()
+ height = int(bx_raw(['fetch-height']))
+ header = q_fetch_header_by_height(self.endpoints['query'], height)
+ self._send_response(query, {'height': height,
+ 'hex': safe_hexlify(header)})
+
+ elif method == 'blockchain.relayfee':
+ self._send_response(query, 0.00001)
+
+ elif method == 'blockchain.scripthash.get_balance':
+ self._send_error(query['id'], {'message': 'Not implemented'})
+
+ elif method == 'blockchain.scripthash.get_history':
+ # BUG: Either in Electrum or libbitcoin scripthash is reversed
+ scripthash = safe_hexlify(unhexlify(query['params'][0])[::-1])
+ hist = fetch_scripthash_history(scripthash)
+ self._send_response(query, hist)
+
+ elif method == 'blockchain.scripthash.get_mempool':
+ # TODO: blockchain.scripthash.get_mempool
+ self._send_error(query['id'], {'message': 'Not implemented'})
+
+ elif method == 'blockchain.scripthash.list_unspent':
+ # TODO: blockchain.scripthash.list_unspent
+ self._send_error(query['id'], {'message': 'Not implemented'})
+
+ elif method == 'blockchain.scripthash.subscribe':
+ # BUG: Either in Electrum or libbitcoin scripthash is reversed
+ scripthash = safe_hexlify(unhexlify(query['params'][0])[::-1])
+ hist = fetch_scripthash_history(scripthash)
+ self.subscribed_scripthash[scripthash] = (True, hist)
+ # TODO: Thread for watching
+ self._send_response(query, electrum_scripthash_status(hist))
+
+ elif method == 'blockchain.scripthash.unsubscribe':
+ scripthash = query['params'][0]
+ if self.subscribed_scripthash.get(scripthash) is True:
+ self.subscribed_scripthash[scripthash] = False
+ self._send_response(query, True)
+ return
+ self._send_response(query, False)
+
+ elif method == 'blockchain.transaction.broadcast':
+ txhex = query['params'][0]
+ _tx = bx_json(['decode-tx', txhex])['transaction']
+ self.log.info('Broadcasting txid %s', _tx['hash'])
+ bx_raw(['broadcast-tx', txhex])
+ self._send_response(query, _tx['hash'])
+
+ elif method == 'blockchain.transaction.get':
+ txid = query['params'][0]
+ verbose = query['params'][1] if len(query['params']) > 1 else False
+ rawtx = q_fetch_tx_by_txid(self.endpoints['query'], txid)
+ if not rawtx:
+ error = {'message': 'txid %s not found' % txid}
+ self._send_error(query['id'], error)
+ return
+ _tx = safe_hexlify(rawtx)
+ if not verbose:
+ self._send_response(query, _tx)
+ return
+ # TODO: Implement with verbose=true
+ error = {'message': 'Not implemented with verbose=True'}
+ self._send_error(query['id'], error)
+
+ elif method == 'blockchain.transaction.get_merkle':
+ txid = query['params'][0]
+ height = query['params'][1]
+ branch, tx_pos = merkle_branch_for_tx_hash(height, txid)
+ if not branch or not tx_pos:
+ self._send_error(query['id'], {'message': 'txid not found'})
+ self._send_response(query, {'merkle': branch, 'pos': int(tx_pos),
+ 'block_height': int(height)})
+
+ elif method == 'blockchain.transaction.id_from_pos':
+ height = query['params'][0]
+ tx_pos = int(query['params'][1])
+ merkle = query['params'][2] if len(query['params']) > 2 else False
+ branch, txid = merkle_branch_for_tx_pos(height, tx_pos)
+ if not txid:
+ error = {'message': 'could not find txid'}
+ self._send_error(query['id'], error)
+ return
+ if not merkle:
+ self._send_response(query, txid)
+ return
+ self._send_response(query, {'tx_hash': txid, 'merkle': branch})
+
+ elif method == 'mempool.get_fee_histogram':
+ # TODO: Implement mempool.get_fee_histogram
+ self._send_response(query, [[0, 0]])
+
+ elif method == 'server.add_peer':
+ self._send_response(query, False)
+
+ elif method == 'server.banner':
+ self._send_response(query, BANNER)
+
+ elif method == 'server.donation_address':
+ self._send_response(query, DONATION_ADDR)
+
+ elif method == 'server.features':
+ ret = {
+ 'genesis_hash': self.genesis,
+ 'hosts': {
+ 'localhost': {'tcp_port': None, 'ssl_port': 50002},
+ },
+ 'protocol_max': SERVER_PROTO_MAX,
+ 'protocol_min': SERVER_PROTO_MIN,
+ 'pruning': None,
+ 'server_version': 'electrum-obelisk %s' % VERSION,
+ 'hash_function': 'sha256',
+ }
+ self._send_response(query, ret)
+
+ elif method == 'server.peers.subscribe':
+ # No peers to report
+ self._send_response(query, [])
+
+ elif method == 'server.ping':
+ self._send_response(query, None)
+
+ elif method == 'server.version':
+ if self.version_called:
+ self.log.warning('Got a subsequent %s call', method)
+ return
+ client_ver = query['params'][1]
+ if isinstance(client_ver, list):
+ client_min, client_max = client_ver[0], client_ver[1]
+ else:
+ client_min = client_max = client_ver
+ version = min(client_max, SERVER_PROTO_MAX)
+ if version < max(client_min, SERVER_PROTO_MIN):
+ self.log.error("Client protocol version %s not supported.",
+ str(client_ver))
+ raise ConnectionRefusedError()
+ # self.version_called = True
+ self._send_response(query, ['electrum-obelisk %s' % VERSION,
+ version])
+
+ else:
+ self.log.error('BUG: Not handling method: "%s" query=%s',
+ method, query)
diff --git a/electrumobelisk/query.py b/electrumobelisk/query.py
@@ -0,0 +1,78 @@
+#!/usr/bin/env python3
+# electrum-obelisk
+# Copyright (C) 2020-2021 Ivan J. <parazyd@dyne.org>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+""" zmq interfacing """
+from binascii import unhexlify
+from struct import pack, unpack
+
+import zmq
+
+
+def q_fetch_header_by_height(endp, height):
+ """ Fetch and return a block header at height as raw bytes """
+ context = zmq.Context()
+ socket = context.socket(zmq.REQ) # pylint: disable=E1101
+ socket.connect(endp)
+ socket.send(b'blockchain.fetch_block_header', zmq.SNDMORE)
+ socket.send(pack('I', 42), zmq.SNDMORE)
+ socket.send(pack('I', int(height)))
+ _ = socket.recv()
+ _ = socket.recv()
+ response_body = socket.recv()
+ _ec = unpack('<I', response_body[0:4])[0]
+ if _ec != 0:
+ return None
+ return response_body[4:]
+
+
+def q_fetch_headers_by_height_count(endp, start_height, count):
+ """ Fetch and return count concatenated headers by height as raw bytes """
+ # Implemented to reuse the socket rather than opening a new one
+ # for each header requested (e.g. by looping q_fetch_header_by_height()).
+ context = zmq.Context()
+ socket = context.socket(zmq.REQ) # pylint: disable=E1101
+ socket.connect(endp)
+ _id = 42
+ res = bytearray()
+ for i in range(count):
+ socket.send(b'blockchain.fetch_block_header', zmq.SNDMORE)
+ socket.send(pack('I', _id), zmq.SNDMORE)
+ socket.send(pack('I', start_height+i))
+ _ = socket.recv()
+ _ = socket.recv()
+ response_body = socket.recv()
+ _ec = unpack('<I', response_body[0:4])[0]
+ if not response_body or _ec != 0:
+ break
+ res.extend(response_body[4:])
+ return res
+
+
+def q_fetch_tx_by_txid(endp, txid):
+ """ Fetch and return a transaction by txid as raw bytes """
+ context = zmq.Context()
+ socket = context.socket(zmq.REQ) # pylint: disable=E1101
+ socket.connect(endp)
+ socket.send(b'blockchain.fetch_transaction2', zmq.SNDMORE)
+ socket.send(pack('I', 42), zmq.SNDMORE)
+ socket.send(unhexlify(txid)[::-1])
+ _ = socket.recv()
+ _ = socket.recv()
+ response_body = socket.recv()
+ _ec = unpack('<I', response_body[0:4])[0]
+ if _ec != 0:
+ return None
+ return response_body[4:]
diff --git a/obelisk b/obelisk
@@ -0,0 +1,232 @@
+#!/usr/bin/env python3
+# electrum-obelisk
+# Copyright (C) 2020-2021 Ivan J. <parazyd@dyne.org>
+# Copyright (C) 2018-2020 Chris Belcher (MIT License)
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+"""
+Main module for electrum-obelisk server
+"""
+import ssl
+import sys
+import socket
+from os.path import join, exists
+from json import dumps, loads
+from json.decoder import JSONDecodeError
+from ipaddress import ip_network, ip_address
+from tempfile import gettempdir
+from configparser import RawConfigParser, NoSectionError
+from logging import getLogger, FileHandler, Formatter, StreamHandler, DEBUG
+from argparse import ArgumentParser
+
+from pkg_resources import resource_filename
+
+from electrumobelisk.bx import bx_raw
+from electrumobelisk.protocol import (VERSION, ElectrumProtocol, DONATION_ADDR)
+
+
+def logger_config(log, config):
+ """ Setup logging """
+ fmt = Formatter(config.get('logging', 'log_format',
+ fallback='%(asctime)s\t%(levelname)s\t%(message)s'))
+ logstream = StreamHandler()
+ logstream.setFormatter(fmt)
+ logstream.setLevel(config.get('logging', 'log_level_stdout',
+ fallback='DEBUG'))
+ log.addHandler(logstream)
+ filename = config.get('logging', 'log_file_location', fallback='')
+ if len(filename.strip()) == 0:
+ filename = join(gettempdir(), 'obelisk.log')
+ logfile = FileHandler(filename, mode=('a' if config.get(
+ 'logging', 'append_log', fallback='false') else 'w'))
+ logfile.setFormatter(fmt)
+ logfile.setLevel(DEBUG)
+ log.addHandler(logfile)
+ log.setLevel(DEBUG)
+ return log, filename
+
+
+
+def get_certs(config):
+ """ Get filepaths to TLS certificate and key """
+ certfile = config.get('electrum-obelisk', 'certfile', fallback=None)
+ keyfile = config.get('electrum-obelisk', 'keyfile', fallback=None)
+ if (certfile and keyfile) and (exists(certfile) and exists(keyfile)):
+ return certfile, keyfile
+
+ certfile = resource_filename('electrumobelisk', 'certs/cert.crt')
+ keyfile = resource_filename('electrumobelisk', 'certs/cert.key')
+ if exists(certfile) and exists(keyfile):
+ return certfile, keyfile
+
+ raise ValueError('invalid cert: %s, key: %s' % (certfile, keyfile))
+
+
+def create_server_socket(hostport):
+ """ Set up listen socket """
+ log = getLogger('electrum-obelisk')
+ server_sock = socket.socket()
+ server_sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+ server_sock.bind(hostport)
+ server_sock.listen(1)
+ log.info('Listening for clients on %s', str(hostport))
+ log.info('Consider donating to electrum-obelisk: %s', DONATION_ADDR)
+ return server_sock
+
+
+def fill_ip_whitelist(config):
+ """ Parses configuration option(s) for IP address whitelist """
+ ip_w = []
+ for i in config.get('electrum-obelisk', 'ip_whitelist').split(' '):
+ if i == '*':
+ # Matches everything
+ ip_w.append(ip_network('0.0.0.0/0'))
+ ip_w.append(ip_network('::0/0'))
+ else:
+ ip_w.append(ip_network(i, strict=False))
+ return ip_w
+
+
+def run_electrum_server(config, chain):
+ """ Basic TLS socket server """
+ log = getLogger('electrum-obelisk')
+ hostport = (config.get('electrum-obelisk', 'host'),
+ int(config.get('electrum-obelisk', 'port')))
+ ip_whitelist = fill_ip_whitelist(config)
+
+ if config.getboolean('electrum-obelisk', 'usetls', fallback=True):
+ certfile, keyfile = get_certs(config)
+ log.debug('Using cert: %s, key: %s', certfile, keyfile)
+
+ broadcast_method = config.get('electrum-obelisk', 'broadcast_method',
+ fallback='own-node')
+ tor_host = config.get('electrum-obelisk', 'tor_host', fallback='localhost')
+ tor_port = int(config.get('electrum-obelisk', 'tor_port', fallback=9050))
+ tor_hostport = (tor_host, tor_port)
+
+ endpoints = {}
+ endpoints['query'] = config.get('electrum-obelisk', 'bs_query')
+ endpoints['heartbeat'] = config.get('electrum-obelisk', 'bs_heartbeat')
+ endpoints['block'] = config.get('electrum-obelisk', 'bs_block')
+ endpoints['transaction'] = config.get('electrum-obelisk', 'bs_transaction')
+
+ protocol = ElectrumProtocol(log, chain, endpoints)
+
+ server_sock = create_server_socket(hostport)
+ # server_sock.settimeout(30)
+
+ while True:
+ sock = None
+ while sock is None:
+ try:
+ sock, addr = server_sock.accept()
+ if not any([ip_address(addr[0]) in ipnet
+ for ipnet in ip_whitelist]):
+ log.debug('%s not in whitelist. Closing...', str(addr[0]))
+ raise ConnectionRefusedError()
+ if config.getboolean('electrum-obelisk', 'usetls',
+ fallback=True):
+ sock = ssl.wrap_socket(sock, server_side=True,
+ certfile=certfile, keyfile=keyfile,
+ ssl_version=ssl.PROTOCOL_TLS)
+ log.debug('sock.accept')
+ except (ConnectionRefusedError, ssl.SSLError, IOError):
+ sock.close()
+ sock = None
+ log.debug('Client connected from %s', str(addr[0]))
+
+ def send_reply_fun(reply):
+ line = dumps(reply)
+ sock.sendall(line.encode('utf-8') + b'\n')
+ log.debug('<= %s', line)
+ protocol.set_send_reply_fun(send_reply_fun)
+
+ try:
+ #sock.settimeout(5)
+ recv_buffer = bytearray()
+ while True:
+ # Loop for replying to client queries
+ try:
+ recv_data = sock.recv(4096)
+ if not recv_data or len(recv_data) == 0:
+ raise EOFError()
+ recv_buffer.extend(recv_data)
+ _lb = recv_buffer.find(b'\n')
+ if _lb == -1:
+ continue
+ while _lb != -1:
+ line = recv_buffer[:_lb].rstrip()
+ recv_buffer = recv_buffer[_lb + 1:]
+ _lb = recv_buffer.find(b'\n')
+ try:
+ line = line.decode('utf-8')
+ query = loads(line)
+ except (UnicodeDecodeError, JSONDecodeError) as err:
+ raise IOError from repr(err)
+ log.debug('=> %s', line)
+ protocol.handle_query(query)
+ except socket.timeout:
+ log.debug('Socket timeout reached')
+ except(IOError, EOFError) as err:
+ if isinstance(err, (EOFError, ConnectionRefusedError)):
+ log.debug('Client disconnected')
+ else:
+ log.debug('IOError: %s', repr(err))
+ try:
+ if sock is not None:
+ sock.close()
+ except IOError:
+ pass
+ protocol.on_disconnect()
+
+def main():
+ """ Main orchestration """
+ parser = ArgumentParser(description='electrum-obelisk %s' % VERSION)
+ parser.add_argument('config_file', help='Path to config file')
+ parser.add_argument('-v', '--version', action='version',
+ version='electrum-obelisk %s' % VERSION)
+ args = parser.parse_args()
+
+ try:
+ config = RawConfigParser()
+ config.read(args.config_file)
+ config.options('electrum-obelisk')
+ except NoSectionError:
+ print(f'Error: Nonexistent config file {args.config_file}')
+ return 1
+
+ log = getLogger('electrum-obelisk')
+ log, logfilename = logger_config(log, config)
+ log.info('Starting electrum-obelisk %s' % VERSION)
+ log.info('Logging to %s' % logfilename)
+
+ chain = config.get('electrum-obelisk', 'chain')
+ if chain not in ['mainnet', 'regtest', 'testnet']:
+ log.error('"chain" is not one of "mainnet", "regtest", or "testnet"')
+ return 1
+
+ if not bx_raw(['fetch-height']):
+ log.error("Couldn't use bx fetch-height. Please check your bx config")
+ return 1
+
+ try:
+ run_electrum_server(config, chain)
+ except KeyboardInterrupt:
+ log.info('Got KeyboardInterrupt, exiting...')
+ return 1
+ return 0
+
+
+if __name__ == '__main__':
+ sys.exit(main())
diff --git a/res/obelisk.png b/res/obelisk.png
Binary files differ.
