[feat] #262: Add 'verify' command to check blocks’ signatures

- Based on DuniterPy 0.56.0 which implements block signature
  verification
- #183: Click progress bar
- Handle BMA anti-spam protection whith an exception
- Possibility to pass starting and ending block numbers to verify them
- Default to 0,0(head) for the full blockchain

silkaj/blocks.py

+"""
+Copyright  2016-2020 Maël Azimi <m.a@moul.re>
+
+Silkaj 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.
+
+Silkaj 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 Silkaj. If not, see <https://www.gnu.org/licenses/>.
+"""
+
+import logging
+from asyncio import sleep
+from click import command, argument, INT, progressbar
+from aiohttp.client_exceptions import ServerDisconnectedError
+
+from duniterpy.api import bma
+from duniterpy.api.client import Client
+from duniterpy.api.errors import DuniterError
+from duniterpy.documents import Block
+from duniterpy.key.verifying_key import VerifyingKey
+
+from silkaj.tools import message_exit, coroutine
+from silkaj.network_tools import EndPoint, HeadBlock
+from silkaj.constants import BMA_MAX_BLOCKS_CHUNK_SIZE
+
+
+@command("verify", help="Verify blocks’ signatures. Range defaults to 0, 0 (head)")
+@argument("from_", default=0, type=INT)
+@argument("to", default=0, type=INT)
+@coroutine
+async def verify_blocks_signatures(from_, to):
+    client = Client(EndPoint().BMA_ENDPOINT)
+
+    if to == 0:
+        to = (await HeadBlock().head_block)["number"]
+    if from_ > to:
+        message_exit("FROM should be lower than TO")
+
+    invalid_blocks_signature = list()
+    chunks_from = range(from_, to + 1, BMA_MAX_BLOCKS_CHUNK_SIZE)
+    with progressbar(chunks_from, label="Processing blocks verification") as bar:
+        for chunk_from in bar:
+            chunk_size = get_chunk_size(from_, to, chunks_from, chunk_from)
+            logging.info(
+                "Processing chunk from block {} to {}".format(
+                    chunk_from, chunk_from + chunk_size
+                )
+            )
+            chunk = await get_chunk(client, chunk_size, chunk_from)
+
+            for block in chunk:
+                block = Block.from_signed_raw(block["raw"] + block["signature"] + "\n")
+                verify_block_signature(invalid_blocks_signature, block)
+
+    await client.close()
+    display_result(from_, to, invalid_blocks_signature)
+
+
+def get_chunk_size(from_, to, chunks_from, chunk_from):
+    """If not last chunk, take the maximum size
+    Otherwise, calculate the size for the last chunk"""
+    if chunk_from != chunks_from[-1]:
+        return BMA_MAX_BLOCKS_CHUNK_SIZE
+    else:
+        return (to + 1 - from_) % BMA_MAX_BLOCKS_CHUNK_SIZE
+
+
+async def get_chunk(client, chunk_size, chunk_from):
+    try:
+        return await client(bma.blockchain.blocks, chunk_size, chunk_from)
+    except ServerDisconnectedError:
+        logging.info("Reach BMA anti-spam protection. Waiting two seconds")
+        await sleep(2)
+        return await client(bma.blockchain.blocks, chunk_size, chunk_from)
+    except DuniterError as error:
+        logging.error(error)
+
+
+def verify_block_signature(invalid_blocks_signature, block):
+    key = VerifyingKey(block.issuer)
+    if not key.verify_document(block):
+        invalid_blocks_signature.append(block.number)
+
+
+def display_result(from_, to, invalid_blocks_signature):
+    print("Within {0}-{1} range, ".format(from_, to), end="")
+    if invalid_blocks_signature:
+        print("blocks with a wrong signature:", *invalid_blocks_signature)
+    else:
+        print("no blocks with a wrong signature.")

silkaj/cli.py

@@ -33,6 +33,7 @@ from silkaj.commands import (
 from silkaj.wot import received_sent_certifications, id_pubkey_correspondence
 from silkaj.auth import generate_auth_file
 from silkaj.license import license_command
+from silkaj.blocks import verify_blocks_signatures
 from silkaj.constants import SILKAJ_VERSION
 
 
@@ -95,6 +96,7 @@ cli.add_command(currency_info)
 cli.add_command(license_command)
 cli.add_command(network_info)
 cli.add_command(send_transaction)
+cli.add_command(verify_blocks_signatures)
 cli.add_command(received_sent_certifications)
 
 

silkaj/constants.py

@@ -25,3 +25,4 @@ ASYNC_SLEEP = 0.1
 SOURCES_PER_TX = 40
 SUCCESS_EXIT_STATUS = 0
 FAILURE_EXIT_STATUS = 1
+BMA_MAX_BLOCKS_CHUNK_SIZE = 5000