import hashlib
import struct
from binascii import unhexlify
import msgpack
from torba.server.hash import hash_to_hex_str
from torba.server.block_processor import BlockProcessor
from lbrynet.schema.uri import parse_lbry_uri
from lbrynet.schema.decode import smart_decode
from lbrynet.extras.wallet.server.model import NameClaim, ClaimInfo, ClaimUpdate, ClaimSupport
class LBRYBlockProcessor(BlockProcessor):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
if self.env.coin.NET == "regtest":
self.prefetcher.polling_delay = 0.5
self.should_validate_signatures = self.env.boolean('VALIDATE_CLAIM_SIGNATURES', False)
self.logger.info("LbryumX Block Processor - Validating signatures: {}".format(self.should_validate_signatures))
def advance_blocks(self, blocks):
# save height, advance blocks as usual, then hook our claim tx processing
height = self.height + 1
super().advance_blocks(blocks)
pending_undo = []
for index, block in enumerate(blocks):
undo = self.advance_claim_txs(block.transactions, height + index)
pending_undo.append((height+index, undo,))
self.db.write_undo(pending_undo)
def advance_claim_txs(self, txs, height):
# TODO: generate claim undo info!
undo_info = []
add_undo = undo_info.append
update_inputs = set()
for tx, txid in txs:
update_inputs.clear()
if tx.has_claims:
for index, output in enumerate(tx.outputs):
claim = output.claim
if isinstance(claim, NameClaim):
add_undo(self.advance_claim_name_transaction(output, height, txid, index))
elif isinstance(claim, ClaimUpdate):
update_input = self.db.get_update_input(claim, tx.inputs)
if update_input:
update_inputs.add(update_input)
add_undo(self.advance_update_claim(output, height, txid, index))
else:
info = (hash_to_hex_str(txid), hash_to_hex_str(claim.claim_id),)
self.logger.error("REJECTED: {} updating {}".format(*info))
elif isinstance(claim, ClaimSupport):
self.advance_support(claim, txid, index, height, output.value)
for txin in tx.inputs:
if txin not in update_inputs:
abandoned_claim_id = self.db.abandon_spent(txin.prev_hash, txin.prev_idx)
if abandoned_claim_id:
add_undo((abandoned_claim_id, self.db.get_claim_info(abandoned_claim_id)))
return undo_info
def advance_update_claim(self, output, height, txid, nout):
claim_id = output.claim.claim_id
claim_info = self.claim_info_from_output(output, txid, nout, height)
old_claim_info = self.db.get_claim_info(claim_id)
self.db.put_claim_id_for_outpoint(old_claim_info.txid, old_claim_info.nout, None)
if old_claim_info.cert_id:
self.db.remove_claim_from_certificate_claims(old_claim_info.cert_id, claim_id)
if claim_info.cert_id:
self.db.put_claim_id_signed_by_cert_id(claim_info.cert_id, claim_id)
self.db.put_claim_info(claim_id, claim_info)
self.db.put_claim_id_for_outpoint(txid, nout, claim_id)
return claim_id, old_claim_info
def advance_claim_name_transaction(self, output, height, txid, nout):
claim_id = claim_id_hash(txid, nout)
claim_info = self.claim_info_from_output(output, txid, nout, height)
if claim_info.cert_id:
self.db.put_claim_id_signed_by_cert_id(claim_info.cert_id, claim_id)
self.db.put_claim_info(claim_id, claim_info)
self.db.put_claim_id_for_outpoint(txid, nout, claim_id)
return claim_id, None
def backup_from_undo_info(self, claim_id, undo_claim_info):
"""
Undo information holds a claim state **before** a transaction changes it
There are 4 possibilities when processing it, of which only 3 are valid ones:
1. the claim is known and the undo info has info, it was an update
2. the claim is known and the undo info doesn't hold any info, it was claimed
3. the claim in unknown and the undo info has info, it was abandoned
4. the claim is unknown and the undo info does't hold info, error!
"""
undo_claim_info = ClaimInfo(*undo_claim_info) if undo_claim_info else None
current_claim_info = self.db.get_claim_info(claim_id)
if current_claim_info and undo_claim_info:
# update, remove current claim
self.db.remove_claim_id_for_outpoint(current_claim_info.txid, current_claim_info.nout)
if current_claim_info.cert_id:
self.db.remove_claim_from_certificate_claims(current_claim_info.cert_id, claim_id)
elif current_claim_info and not undo_claim_info:
# claim, abandon it
self.db.abandon_spent(current_claim_info.txid, current_claim_info.nout)
elif not current_claim_info and undo_claim_info:
# abandon, reclaim it (happens below)
pass
else:
# should never happen, unless the database got into an inconsistent state
raise Exception("Unexpected situation occurred on backup, this means the database is inconsistent. "
"Please report. Resetting the data folder (reindex) solves it for now.")
if undo_claim_info:
self.db.put_claim_info(claim_id, undo_claim_info)
if undo_claim_info.cert_id:
cert_id = self._checksig(undo_claim_info.name, undo_claim_info.value, undo_claim_info.address)
self.db.put_claim_id_signed_by_cert_id(cert_id, claim_id)
self.db.put_claim_id_for_outpoint(undo_claim_info.txid, undo_claim_info.nout, claim_id)
def backup_txs(self, txs):
self.logger.info("Reorg at height {} with {} transactions.".format(self.height, len(txs)))
undo_info = msgpack.loads(self.db.claim_undo_db.get(struct.pack(">I", self.height)), use_list=False)
for claim_id, undo_claim_info in reversed(undo_info):
self.backup_from_undo_info(claim_id, undo_claim_info)
return super().backup_txs(txs)
def backup_blocks(self, raw_blocks):
self.db.batched_flush_claims()
super().backup_blocks(raw_blocks=raw_blocks)
self.db.batched_flush_claims()
async def flush(self, flush_utxos):
self.db.batched_flush_claims()
return await super().flush(flush_utxos)
def advance_support(self, claim_support, txid, nout, height, amount):
# TODO: check for more controller claim rules, like takeover or ordering
pass
def claim_info_from_output(self, output, txid, nout, height):
amount = output.value
address = self.coin.address_from_script(output.pk_script)
name, value, cert_id = output.claim.name, output.claim.value, None
assert txid and address
cert_id = self._checksig(name, value, address)
return ClaimInfo(name, value, txid, nout, amount, address, height, cert_id)
def _checksig(self, name, value, address):
try:
parse_lbry_uri(name.decode()) # skip invalid names
claim_dict = smart_decode(value)
cert_id = unhexlify(claim_dict.certificate_id)[::-1]
if not self.should_validate_signatures:
return cert_id
if cert_id:
cert_claim = self.db.get_claim_info(cert_id)
if cert_claim:
certificate = smart_decode(cert_claim.value)
claim_dict.validate_signature(address, certificate)
return cert_id
except Exception as e:
pass
def claim_id_hash(txid, n):
# TODO: This should be in lbryschema
packed = txid + struct.pack('>I', n)
md = hashlib.new('ripemd160')
md.update(hashlib.sha256(packed).digest())
return md.digest()