Merge #19010: net processing: Add support for getcfheaders

5308c97cca [test] Add test for cfheaders (Jim Posen)
f6b58c1506 [net processing] Message handling for getcfheaders. (Jim Posen)
3bdc7c2d39 [doc] Add comment for m_headers_cache (John Newbery)

Pull request description:

  Support `getcfheaders` requests when `-peerblockfilters` is set.

  Does not advertise compact filter support in version messages.

ACKs for top commit:
  jkczyz:
    ACK 5308c97cca
  MarcoFalke:
    re-ACK 5308c97cca , only change is doc related 🗂
  theStack:
    ACK 5308c97cca 🚀

Tree-SHA512: 240fc654f6f634c191d9f7628b6c4801f87ed514a1dd55c7de5d454d4012d1c09509a2d5a246bc7da445cd920252b4cd56a493c060cdb207b04af4ffe53b95f7

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 @@ from test_framework.messages import (
     msg_block,
     MSG_BLOCK,
     msg_blocktxn,
+    msg_cfheaders,
     msg_cfcheckpt,
     msg_cmpctblock,
     msg_feefilter,
@@ -68,6 +69,7 @@ MESSAGEMAP = {
     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 @@ class P2PInterface(P2PConnection):
     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