Merge bitcoin/bitcoin#21872: net: Sanitize message type for logging

09205b33aa74e385caa2803aa6febc18ad1efa32 net: Clarify message header validation errors (W. J. van der Laan)
955eee76803c098978cf0bbc7f1f6d3c230544e2 net: Sanitize message type for logging (W. J. van der Laan)

Pull request description:

  - Use `SanitizeString` when logging message errors to make sure that the message type is sanitized. I have checked all logging in `net.cpp`.

  - For the `MESSAGESTART` error don't inspect and log header details at all: receiving invalid start bytes makes it likely that the packet isn't even formatted as valid P2P message. Logging the four unexpected start bytes (as hex) should be enough.

  - Update `p2p_invalid_messages.py` test to check this.

  - Improve error messages in a second commit.

  Issue reported by gmaxwell.

ACKs for top commit:
  MarcoFalke:
    re-ACK 09205b33aa74e385caa2803aa6febc18ad1efa32 only change is log message fixup 🔂
  practicalswift:
    re-ACK 09205b33aa74e385caa2803aa6febc18ad1efa32

Tree-SHA512: 8fe5326af135cfcf39ea953d9074a8c966b9b85a810b06a2c45b8a745cf115de4f321e72fc769709d6bbecfc5953aab83176db6735b04c0bc6796f59272cadce

1 files changed, 5 insertions, 5 deletions

diff --git a/test/functional/p2p_invalid_messages.py b/test/functional/p2p_invalid_messages.py
index c0b3c2cb12..788a81d4af 100755
--- a/test/functional/p2p_invalid_messages.py
+++ b/test/functional/p2p_invalid_messages.py
@@ -37,7 +37,7 @@ VALID_DATA_LIMIT = MAX_PROTOCOL_MESSAGE_LENGTH - 5  # Account for the 5-byte len
 class msg_unrecognized:
     """Nonsensical message. Modeled after similar types in test_framework.messages."""
 
-    msgtype = b'badmsg'
+    msgtype = b'badmsg\x01'
 
     def __init__(self, *, str_data):
         self.str_data = str_data.encode() if not isinstance(str_data, bytes) else str_data
@@ -104,7 +104,7 @@ class InvalidMessagesTest(BitcoinTestFramework):
     def test_magic_bytes(self):
         self.log.info("Test message with invalid magic bytes disconnects peer")
         conn = self.nodes[0].add_p2p_connection(P2PDataStore())
-        with self.nodes[0].assert_debug_log(['HEADER ERROR - MESSAGESTART (badmsg, 2 bytes), received ffffffff']):
+        with self.nodes[0].assert_debug_log(['Header error: Wrong MessageStart ffffffff received']):
             msg = conn.build_message(msg_unrecognized(str_data="d"))
             # modify magic bytes
             msg = b'\xff' * 4 + msg[4:]
@@ -115,7 +115,7 @@ class InvalidMessagesTest(BitcoinTestFramework):
     def test_checksum(self):
         self.log.info("Test message with invalid checksum logs an error")
         conn = self.nodes[0].add_p2p_connection(P2PDataStore())
-        with self.nodes[0].assert_debug_log(['CHECKSUM ERROR (badmsg, 2 bytes), expected 78df0a04 was ffffffff']):
+        with self.nodes[0].assert_debug_log(['Header error: Wrong checksum (badmsg, 2 bytes), expected 78df0a04 was ffffffff']):
             msg = conn.build_message(msg_unrecognized(str_data="d"))
             # Checksum is after start bytes (4B), message type (12B), len (4B)
             cut_len = 4 + 12 + 4
@@ -130,7 +130,7 @@ class InvalidMessagesTest(BitcoinTestFramework):
     def test_size(self):
         self.log.info("Test message with oversized payload disconnects peer")
         conn = self.nodes[0].add_p2p_connection(P2PDataStore())
-        with self.nodes[0].assert_debug_log(['HEADER ERROR - SIZE (badmsg, 4000001 bytes)']):
+        with self.nodes[0].assert_debug_log(['Header error: Size too large (badmsg, 4000001 bytes)']):
             msg = msg_unrecognized(str_data="d" * (VALID_DATA_LIMIT + 1))
             msg = conn.build_message(msg)
             conn.send_raw_message(msg)
@@ -140,7 +140,7 @@ class InvalidMessagesTest(BitcoinTestFramework):
     def test_msgtype(self):
         self.log.info("Test message with invalid message type logs an error")
         conn = self.nodes[0].add_p2p_connection(P2PDataStore())
-        with self.nodes[0].assert_debug_log(['HEADER ERROR - COMMAND']):
+        with self.nodes[0].assert_debug_log(['Header error: Invalid message type']):
             msg = msg_unrecognized(str_data="d")
             msg = conn.build_message(msg)
             # Modify msgtype