[test] Add test for cfheaders

Author: jimpo

test/functional/p2p_blockfilters.py

@@ -5,12 +5,16 @@
 """Tests NODE_COMPACT_FILTERS (BIP 157/158).
 
 Tests that a node configured with -blockfilterindex and -peerblockfilters can serve
-cfcheckpts.
+cfheaders and cfcheckpts.
 """
 
 from test_framework.messages import (
     FILTER_TYPE_BASIC,
+    hash256,
     msg_getcfcheckpt,
+    msg_getcfheaders,
+    ser_uint256,
+    uint256_from_str,
 )
 from test_framework.mininode import P2PInterface
 from test_framework.test_framework import BitcoinTestFramework
@@ -100,12 +104,45 @@ def run_test(self):
             [int(header, 16) for header in (stale_cfcheckpt,)]
         )
 
+        self.log.info("Check that peers can fetch cfheaders on active chain.")
+        request = msg_getcfheaders(
+            filter_type=FILTER_TYPE_BASIC,
+            start_height=1,
+            stop_hash=int(main_block_hash, 16)
+        )
+        node0.send_and_ping(request)
+        response = node0.last_message['cfheaders']
+        assert_equal(len(response.hashes), 1000)
+        assert_equal(
+            compute_last_header(response.prev_header, response.hashes),
+            int(main_cfcheckpt, 16)
+        )
+
+        self.log.info("Check that peers can fetch cfheaders on stale chain.")
+        request = msg_getcfheaders(
+            filter_type=FILTER_TYPE_BASIC,
+            start_height=1,
+            stop_hash=int(stale_block_hash, 16)
+        )
+        node0.send_and_ping(request)
+        response = node0.last_message['cfheaders']
+        assert_equal(len(response.hashes), 1000)
+        assert_equal(
+            compute_last_header(response.prev_header, response.hashes),
+            int(stale_cfcheckpt, 16)
+        )
+
         self.log.info("Requests to node 1 without NODE_COMPACT_FILTERS results in disconnection.")
         requests = [
             msg_getcfcheckpt(
                 filter_type=FILTER_TYPE_BASIC,
                 stop_hash=int(main_block_hash, 16)
             ),
+            msg_getcfheaders(
+                filter_type=FILTER_TYPE_BASIC,
+                start_height=1000,
+                stop_hash=int(main_block_hash, 16)
+            ),
         ]
         for request in requests:
             node1 = self.nodes[1].add_p2p_connection(P2PInterface())
@@ -114,6 +151,12 @@ def run_test(self):
 
         self.log.info("Check that invalid requests result in disconnection.")
         requests = [
+            # Requesting too many filter headers results in disconnection.
+            msg_getcfheaders(
+                filter_type=FILTER_TYPE_BASIC,
+                start_height=0,
+                stop_hash=int(tip_hash, 16)
+            ),
             # Requesting unknown filter type results in disconnection.
             msg_getcfcheckpt(
                 filter_type=255,
@@ -130,5 +173,12 @@ def run_test(self):
             node0.send_message(request)
             node0.wait_for_disconnect()
 
+def compute_last_header(prev_header, hashes):
+    """Compute the last filter header from a starting header and a sequence of filter hashes."""
+    header = ser_uint256(prev_header)
+    for filter_hash in hashes:
+        header = hash256(ser_uint256(filter_hash) + header)
+    return uint256_from_str(header)
+
 if __name__ == '__main__':
     CompactFiltersTest().main()

test/functional/test_framework/messages.py

@@ -1516,6 +1516,59 @@ class msg_no_witness_blocktxn(msg_blocktxn):
     def serialize(self):
         return self.block_transactions.serialize(with_witness=False)
 
+class msg_getcfheaders:
+    __slots__ = ("filter_type", "start_height", "stop_hash")
+    msgtype =  b"getcfheaders"
+
+    def __init__(self, filter_type, start_height, stop_hash):
+        self.filter_type = filter_type
+        self.start_height = start_height
+        self.stop_hash = stop_hash
+
+    def deserialize(self, f):
+        self.filter_type = struct.unpack("<B", f.read(1))[0]
+        self.start_height = struct.unpack("<I", f.read(4))[0]
+        self.stop_hash = deser_uint256(f)
+
+    def serialize(self):
+        r = b""
+        r += struct.pack("<B", self.filter_type)
+        r += struct.pack("<I", self.start_height)
+        r += ser_uint256(self.stop_hash)
+        return r
+
+    def __repr__(self):
+        return "msg_getcfheaders(filter_type={:#x}, start_height={}, stop_hash={:x})".format(
+            self.filter_type, self.start_height, self.stop_hash)
+
+class msg_cfheaders:
+    __slots__ = ("filter_type", "stop_hash", "prev_header", "hashes")
+    msgtype =  b"cfheaders"
+
+    def __init__(self, filter_type=None, stop_hash=None, prev_header=None, hashes=None):
+        self.filter_type = filter_type
+        self.stop_hash = stop_hash
+        self.prev_header = prev_header
+        self.hashes = hashes
+
+    def deserialize(self, f):
+        self.filter_type = struct.unpack("<B", f.read(1))[0]
+        self.stop_hash = deser_uint256(f)
+        self.prev_header = deser_uint256(f)
+        self.hashes = deser_uint256_vector(f)
+
+    def serialize(self):
+        r = b""
+        r += struct.pack("<B", self.filter_type)
+        r += ser_uint256(self.stop_hash)
+        r += ser_uint256(self.prev_header)
+        r += ser_uint256_vector(self.hashes)
+        return r
+
+    def __repr__(self):
+        return "msg_cfheaders(filter_type={:#x}, stop_hash={:x})".format(
+            self.filter_type, self.stop_hash)
+
 class msg_getcfcheckpt:
     __slots__ = ("filter_type", "stop_hash")
     msgtype =  b"getcfcheckpt"

test/functional/test_framework/mininode.py

@@ -31,6 +31,7 @@
     msg_block,
     MSG_BLOCK,
     msg_blocktxn,
+    msg_cfheaders,
     msg_cfcheckpt,
     msg_cmpctblock,
     msg_feefilter,
@@ -68,6 +69,7 @@
     b"addr": msg_addr,
     b"block": msg_block,
     b"blocktxn": msg_blocktxn,
+    b"cfheaders": msg_cfheaders,
     b"cfcheckpt": msg_cfcheckpt,
     b"cmpctblock": msg_cmpctblock,
     b"feefilter": msg_feefilter,
@@ -330,6 +332,7 @@ def on_close(self):
     def on_addr(self, message): pass
     def on_block(self, message): pass
     def on_blocktxn(self, message): pass
+    def on_cfheaders(self, message): pass
     def on_cfcheckpt(self, message): pass
     def on_cmpctblock(self, message): pass
     def on_feefilter(self, message): pass