- Make const things const.
- Replace conditional return with assert.
- Don't log the peer's IP address.
- Log the name Misbehaving directly instead of relying on __func__.
Misbehaving() could optionally take a debug string for printing to the
log file. Make this mandatory and always provide the string.
A couple of additional minor changes:
- remove the unnecessary forward declaration of Misbehaving()
- don't include the nodeid or newline in the passed debug message.
Misbehaving() adds these itself.
655b195747 [net processing] Continue SendMessages processing if not disconnecting peer (John Newbery)
a49781e56d [net processing] Only call MaybeDiscourageAndDisconnect from SendMessages (John Newbery)
a1d5a428a2 [net processing] Fix bad indentation in SendMessages() (John Newbery)
1a1c23f8d4 [net processing] Change cs_main TRY_LOCK to LOCK in SendMessages() (John Newbery)
Pull request description:
The motivation for this PR is to reduce the scope of cs_main locking in misbehavior logic. It is the first set of commits from a larger branch to move the misbehavior data out of CNodeState and into a new struct that doesn't take cs_main.
There are some very minor behavior changes in this branch, such as:
- Not checking for discouragement/disconnect in `ProcessMessages()` (and instead relying on the following check in `SendMessages()`)
- Checking for discouragement/disconnect as the first action in `SendMessages()` (and not doing ping message sending first)
- Continuing through `SendMessages()` if `MaybeDiscourageAndDisconnect()` doesn't disconnect the peer (rather than dropping out of `SendMessages()`
ACKs for top commit:
jonatack:
re-ACK 655b195 per `git range-diff 505b4ed f54af5e 655b195`, code/commit messages review, a bit of code history, and debug build.
MarcoFalke:
ACK 655b195747 only some style-nits 🚁
promag:
Code review ACK 655b195747.
ariard:
Code Review ACK 655b195
Tree-SHA512: fd6d7bc6bb789f5fb7771fb6a45f61a8faba32af93b766554f562144f9631d15c9cc849a383e71743ef73e610b4ee14853666f6fbf08a3ae35176d48c76c65d3
Previously, TX_WITNESS_MUTATED could be returned during transaction validation
for either transactions that had a witness that was non-standard, or for
transactions that had no witness but were invalid due to segwit validation
rules.
However, for txid/wtxid-relay considerations, net_processing distinguishes the
witness stripped case separately, because it affects whether a wtxid should be
able to be added to the reject filter. It is safe to add the wtxid of a
witness-mutated transaction to the filter (as that wtxid shouldn't collide with
the txid, and hence it wouldn't interfere with transaction relay from
txid-relay peers), but it is not safe to add the wtxid (== txid) of a
witness-stripped transaction to the filter, because that would interfere with
relay of another transaction with the same txid (but different wtxid) when
relaying from txid-relay peers.
Also updates the comment explaining this logic, and explaining that we can get
rid of this complexity once there's a sufficient deployment of wtxid-relaying
peers on the network.
Using both txid and wtxid-based relay with peers means that we could sometimes
download the same transaction twice, if announced via two different hashes from
different peers.
Use a heuristic of delaying txid-peer-getdata requests by 2 seconds, if we have
at least one wtxid-based peer.
This adds a field to CNodeState that tracks whether to relay transactions with
that peer via wtxid, instead of txid. As of this commit the field will always
be false, but in a later commit we will add a way to negotiate turning this on
via p2p messages exchanged with the peer.
Previously, we only added txids to recentRejects if we were sure that the
transaction couldn't have had the wrong witness (either because the witness was
malleated or stripped).
In preparation for wtxid-based relay, we can observe that txid == wtxid for
transactions that have no witness, and add the wtxid of rejected transactions,
provided the transaction wasn't a witness-stripped one. This means that we now
add more data to the filter (as prior to this commit, any transaction with a
witness that failed to be accepted was being skipped for inclusion in the
filter) but witness malleation should still not interfere with relay of a valid
segwit transaction, because the txid of a segwit transaction would not be added
to the filter after failing validation.
In the future, having wtxids in the recent rejects filter will allow us to
skip downloading the same wtxid multiple times, once our peers use wtxids for
transaction relay.
This is in preparation for wtxid-based invs (we need to be able to tell whether
we AlreadyHave() a transaction based on either txid or wtxid).
This also double the size of the bloom filter, which is overkill, but still
uses a manageable amount of memory.
0c8461a88e refactor: replace CConnman pointers by references in net_processing.cpp (Sebastian Falbesoner)
Pull request description:
This is a follow-up to the recently merged PR https://github.com/bitcoin/bitcoin/pull/19053, replacing ~~two more types of~~ one more type of pointer (CConnman) by references to increase the code quality -- pointers should either check for `nullptr` or be replaced by references, and the latter strategy seems to be more reasonable.
Again, to keep the review burden managable, the changes are kept simple,
* only tackling `CConnman*` ~~and `BanMan*`~~ pointers
* only within the net_processing module, i.e. no changes that would need adaption in other modules
* keeping the names of the variables as they are
ACKs for top commit:
jnewbery:
utACK 0c8461a88e
MarcoFalke:
ACK 0c8461a88e🕧
Tree-SHA512: 79dc05144bcfb5e0bbc62180285aadcc6199f044fa3016c0f54f7b7f45037415260970037bd63b18fafefb8aef448549dae14b780bafb540fa2373f493a17f71
fa9f20b647 log: Properly log txs rejected from mempool (MarcoFalke)
Pull request description:
Currently `CheckTxInputs` rejections from the mempool are the only rejections that log directly and unconditionally to debug.log instead of leaving it to the caller. This has multiple issues:
* A rejected RPC transaction will log a redundant failure reason to debug log. All other failures are merely reported to the RPC user.
* A rejected p2p transaction will log the failure twice. Once with the `MEMPOOLREJ` flag, and once unconditionally.
* A rejected orphan transaction will log no failure.
Fix all issues by simply returning the state to the caller, like it is done for all other rejections.
The patch includes whitespace fixups to highlight relevant parts of the codebase and simplify review.
ACKs for top commit:
naumenkogs:
utACK fa9f20b647
rajarshimaitra:
Concept ACK. Compiled and ran tests. `fa9f20b`
jnewbery:
code review ACK fa9f20b647
Tree-SHA512: 86cc17b2a9239c01c4fc3f254ad48ee1d3883266966b9811030176338b9ac3deaea7ea5babfb8bbf739d7440154e30011fede8f9313175f199d4a062af6494f7
Although we currently don't do this, it should be possible to create a
CConnman or PeerLogicValidation without a Banman instance. Therefore
always check that banman exists before dereferencing the pointer.
Also add comments to the m_banman members of CConnman and
PeerLogicValidation to document that these may be nullptr.
f32c408f3a Make sure unconfirmed parents are requestable (Pieter Wuille)
c4626bcd21 Drop setInventoryTxToSend based filtering (Pieter Wuille)
43f02ccbff Only respond to requests for recently announced transactions (Pieter Wuille)
b24a17f039 Introduce constant for mempool-based relay separate from mapRelay caching (Pieter Wuille)
a9bc563803 Swap relay pool and mempool lookup (Pieter Wuille)
Pull request description:
This implements the follow-up suggested here: https://github.com/bitcoin/bitcoin/pull/18861#issuecomment-627630111 . Instead of checking `setInventoryTxToSend`, maintain an explicit bloom filter with the 3500 most recently announced invs, and permit fetching any of these as long as they're in the relay pool or the mempool. In addition, permit relay from the mempool after just 2 minutes instead of 15.
This:
* Fixes the brief opportunity an attacker has to request unannounced invs just after the connection is established (pointed out by naumenkogs, see https://github.com/bitcoin/bitcoin/pull/18861#issuecomment-627627010).
* Guarantees that locally resubmitted invs after `filterInventoryKnown` rolls over can still be requested (pointed out by luke-jr, see https://github.com/bitcoin/bitcoin/pull/18861#discussion_r419695831).
It adds 37 KiB of filter per peer.
This is also a step towards dropping the relay pool entirely and always relaying from the mempool directly (see #17303), but that is still blocked by dealing properly with NOTFOUNDs (see #18238).
ACKs for top commit:
jnewbery:
reACK f32c408f3
jonatack:
re-ACK f32c408 per `git range-diff f7c19e8 2da7ee3 f32c408` and redid the following: code review, thought about motivation, DoS and privacy aspects, debug build to check for warnings after updating Clang from 6 to 11 since last review.
ajtowns:
re-ACK f32c408f3a
Tree-SHA512: aa05b9fd01bad59581c4ec91836a52d7415dc933fa49d4c4adced79aa25aaad51e11166357e8c8b29fbf6021a7401b98c21b850b5d8e8ad773fdb5d6608e1e85
fab5586122 doc: Use precise permission flags where possible (MarcoFalke)
Pull request description:
Instead of mentioning the all-encompassing `-whitelist*` settings, change the docs to mention the exact permission flag that will influence the behaviour.
This is needed because in the future, the too-broad `-whitelist*` settings (they either include *all* permission flags or apply to *all* peers) might be deprecated to require the permission flags to be enumerated.
Alternatively, in the future there could be an RPC to set the net permission flags on an existing connection, in which case the `-whitelist*` terminology is of no help.
ACKs for top commit:
jnewbery:
reACK fab5586122
fjahr:
Code review ACK fab5586122
jonatack:
ACK fab5586122
Tree-SHA512: c7dea3e577d90103bb2b0ffab7b7c8640b388932a3a880f69e2b70747fc9213dc1f437085671fd54c902ec2a578458b8a2fae6dbe076642fb88efbf9fa9e679c
If we don't disconnect a peer in MaybeDiscourageAndDisconnect because it
has NOBAN permissions or it's a manual connection, continue SendMessages
processing rather than exiting early.
The previous behaviour was that we'd miss the SendMessages processing on
this iteration of the MessageHandler loop. That's not a problem since
SendMessages() would just be called again on the next iteration, but it
was slightly inefficient and confusing.
`nMisbehavior` is a tally in `CNodeState` that can be incremented from
anywhere. That almost always happens inside a `ProcessMessages()` call
(because we increment the misbehavior score when receiving a bad
messages from a peer), but not always. See, for example, the call to
`MaybePunishNodeForBlock()` inside `BlockChecked()`, which is an
asynchronous callback from the validation interface, executed on the
scheduler thread.
As long as `MaybeDiscourageAndDisconnect()` is called regularly for the
node, then the misbehavior score exceeding the 100 threshold will
eventually result in the peer being punished. It doesn't really matter
where that `MaybeDiscourageAndDisconnect()` happens, but it makes most
sense in `SendMessages()` which is where we do general peer
housekeeping/maintenance.
Therefore, remove the `MaybeDiscourageAndDisconnect()` call in
`ProcessMessages()` and move the `MaybeDiscourageAndDisconnect()` call
in `SendMessages()` to the top of the function. This moves it out of the
cs_main lock scope, so take that lock directly inside
`MaybeDiscourageAndDisconnect()`.
Historic note: `MaybeDiscourageAndDisconnect()` was previously
`SendRejectsAndCheckIfBanned()`, and before that was just sending
rejects. All of those things required cs_main, which is why
`MaybeDiscourageAndDisconnect()` was called after the ping logic.
This was changed to TRY_LOCK in #1117 to fix a potential deadlock
between cs_main and cs_vSend. cs_vSend was split into cs_vSend and
cs_sendProcessing in #9535 (and cs_sendProcessing was changed from a
TRY_LOCK to a LOCK in the same PR).
Since cs_vSend can no longer be taken before cs_main, revert this to a
LOCK().
This commit leaves part of the code with bad indentation. That is fixed
by the next (whitespace change only) commit.
57b0c0a93a Drop CADDR_TIME_VERSION checks now that MIN_PEER_PROTO_VERSION is greater (Ben Woosley)
Pull request description:
We do not connect to peers older than 31800
ACKs for top commit:
sipa:
Code reivew ACK 57b0c0a93a
jnewbery:
Code review ACK 57b0c0a93a
vasild:
ACK 57b0c0a9
Tree-SHA512: e1ca7c9203cbad83ab7c7a2312777ad07ed6a16119169b256648b8a8738c260a5168acdd4fb33f6e4b17f51ec7e033e110b76bde55b4e3b2d444dc02c01bc2b1
fa3365430c net: Use mockable time for ping/pong, add tests (MarcoFalke)
faab4aaf2f util: Add count_microseconds helper (MarcoFalke)
Pull request description:
Switch `CNode::m_ping_start` and `CNetMessage::m_time` to mockable time, so that tests can be added.
Mockable time is also type-safe, since it uses `std::chrono`
ACKs for top commit:
jonatack:
Code review re-ACK fa33654 re-read code, verified rebase per `git range-diff 4b5c919 fa94d6f fa33654`, previous tested ACKs still valid
troygiorshev:
ACK fa3365430c
Tree-SHA512: 7d632bd6019ce7c882029e71b667a61517e783af82755a85dd979ef09380934e172dec8b8f91d57b200a30a6e096aeaf01f19fee7f3aed0e0e871c72eb44d70e
... unless they're UNCONDITIONAL_RELAY_DELAY old, or there has been
a response to a MEMPOOL request in the mean time.
This is accomplished using a rolling Bloom filter for the last
3500 announced transactions. The probability of seeing more than 100
broadcast events (which can be up to 35 txids each) in 2 minutes for
an outbound peer (where the average frequency is one per minute), is
less than 1 in a million.
This constant is set to 2 minutes, rather than 15. This is still many times
larger than the transaction broadcast interval (2s for outbound, 5s for
inbound), so it should be acceptable for peers to know what our contents of
the mempool was that long ago.
e8a2822119 [net] Don't try to take cs_inventory before deleting CNode (John Newbery)
3556227ddd [net] Make cs_inventory a non-recursive mutex (John Newbery)
344e831de5 [net processing] Remove PushBlockInventory and PushBlockHash (John Newbery)
Pull request description:
- Remove PushBlockInventory() and PushBlockHash(). These are one-line functions that can easy be inlined into the calling code. Doing so also allows us to eliminate the one place that cs_inventory is recursively locked.
- Make cs_inventory a nonrecursive mutex
- Remove a redundant TRY_LOCK of cs_inventory when deleting CNode.
ACKs for top commit:
sipa:
utACK e8a2822119
MarcoFalke:
ACK e8a2822119🍬
hebasto:
re-ACK e8a2822119
Tree-SHA512: dbc721d102cdef7b5827a8f2549daf8b54f543050266999a7ea56c9f36618565b71e31ce0beb1209ba2db43d15388be173355a03fb6db8ad24e2475b145050bd
2ad58381ff Clean up separated ban/discourage interface (Pieter Wuille)
b691f2df5f Replace automatic bans with discouragement filter (Pieter Wuille)
Pull request description:
This patch improves performance and resource usage around IP addresses that are banned for misbehavior. They're already not actually banned since #14929, as connections from them are still allowed, but they are preferred for eviction if the inbound connection slots are full.
Stop treating these like manually banned IP ranges, and instead just keep them in a rolling Bloom filter of misbehaving nodes, which isn't persisted to disk or exposed through the ban framework. The effect remains the same: preferred for eviction, avoided for outgoing connections, and not relayed to other peers.
Also change the name of this mechanism to "discouraged" to better reflect reality.
ACKs for top commit:
naumenkogs:
utACK 2ad58381ff
amitiuttarwar:
code review ACK 2ad58381ff
jonatack:
ACK 2ad5838 per changes since last review `git range-diff 3276c14 1f7e0ca 2ad5838`
jnewbery:
Code review ACK 2ad58381ff
Tree-SHA512: 5dedef401d9cbfa026812651303e6286223563dbeed7a10766ed536ac9e3f29ed4bd0df29cc6deadceeb35cbe9f066346add14ef0833958ca9f93d123fe7aab5
fab80fef61 refactor: Remove unused EnsureChainman (MarcoFalke)
fa34587f1c scripted-diff: Replace EnsureChainman with Assert in unit tests (MarcoFalke)
fa6ef701ad util: Add Assert identity function (MarcoFalke)
fa457fbd33 move-only: Move NDEBUG compile time check to util/check (MarcoFalke)
Pull request description:
The utility function is primarily useful to dereference pointer types, which are known to be not null at that time.
For example, the ArgsManager is known to exist when the wallets are started: https://github.com/bitcoin/bitcoin/pull/18923/files#diff-fdb2a1a1d8bc790fcddeb6cf5a42ac55R503 . Instead of silently relying on that assumption, `Assert` can be used to abort the program and avoid UB should the assumption ever be violated.
ACKs for top commit:
promag:
Tested ACK fab80fef61.
ryanofsky:
Code review ACK fab80fef61
Tree-SHA512: 830fba10152ba17d47c4dd42809c7e26f9fe6d38e17a2d5b3f054fd644a5c4c9841286ac421ec9bb28cea9f5faeb659740fcf00de6cc589d423fee7694c42d16
This patch improves performance and resource usage around IP
addresses that are banned for misbehavior. They're already not
actually banned, as connections from them are still allowed,
but they are preferred for eviction if the inbound connection
slots are full.
Stop treating these like manually banned IP ranges, and instead
just keep them in a rolling Bloom filter of misbehaving nodes,
which isn't persisted to disk or exposed through the ban
framework. The effect remains the same: preferred for eviction,
avoided for outgoing connections, and not relayed to other peers.
Also change the name of this mechanism to better reflect reality;
they're not banned, just discouraged.
Contains release notes and several interface improvements by
John Newbery.
fa525e4d1c net: Avoid wasting inv traffic during IBD (MarcoFalke)
fa06d7e934 refactor: block import implies IsInitialBlockDownload (MarcoFalke)
faba65e696 Add ChainstateManager::ActiveChainstate (MarcoFalke)
fabf3d64ff test: Add FeeFilterRounder test (MarcoFalke)
Pull request description:
Tx-inv messages are ignored during IBD, so it would be nice if we told peers to not send them in the first place. Do that by sending two `feefilter` messages: One when the connection is made (and the node is in IBD), and another one when the node leaves IBD.
ACKs for top commit:
jamesob:
ACK fa525e4d1c ([`jamesob/ackr/19204.1.MarcoFalke.p2p_reduce_inv_traffic_d`](https://github.com/jamesob/bitcoin/tree/ackr/19204.1.MarcoFalke.p2p_reduce_inv_traffic_d))
naumenkogs:
utACK fa525e4
gzhao408:
ACK fa525e4d1c
jonatack:
re-ACK fa525e4 checked diff `git range-diff 19612ca fa8a66c fa525e4`, re-reviewed, ran tests, ran a custom p2p IBD behavior test at 9321e0f223.
hebasto:
re-ACK fa525e4d1c, only rebased since the [previous](https://github.com/bitcoin/bitcoin/pull/19204#pullrequestreview-429519667) review (verified with `git range-diff`).
Tree-SHA512: 2c22a5def9822396fca45d808b165b636f1143c4bdb2eaa5c7e977f1f18e8b10c86d4c180da488def38416cf3076a26de15014dfd4d86b2a7e5af88c74afb8eb
