Merge #17004: validation: Remove REJECT code from CValidationState

9075d13153ce06cd59a45644831ecc43126e1e82 [docs] Add release notes for removal of REJECT reasons (John Newbery)
04a2f326ec0f06fb4fce1c4f93500752f05dede8 [validation] Fix REJECT message comments (John Newbery)
e9d5a59e34ff2d538d8f5315efd9908bf24d0fdc [validation] Remove REJECT code from CValidationState (John Newbery)
0053e16714323c1694c834fdca74f064a1a33529 [logging] Don't log REJECT code when transaction is rejected (John Newbery)
a1a07cfe99fc8cee30ba5976dc36b47b1f6532ab [validation] Fix peer punishment for bad blocks (John Newbery)

Pull request description:

  We no longer send BIP 61 REJECT messages, so there's no need to set
  a REJECT code in the CValidationState object.

  Note that there is a minor bug fix in p2p behaviour here. Because the
  call to `MaybePunishNode()` in `PeerLogicValidation::BlockChecked()` only
  previously happened if the REJECT code was > 0 and < `REJECT_INTERNAL`,
  then there are cases were `MaybePunishNode()` can get called where it
  wasn't previously:

  - when `AcceptBlockHeader()` fails with `CACHED_INVALID`.
  - when `AcceptBlockHeader()` fails with `BLOCK_MISSING_PREV`.

  Note that `BlockChecked()` cannot fail with an 'internal' reject code. The
  only internal reject code was `REJECT_HIGHFEE`, which was only set in
  ATMP.

  This reverts a minor bug introduced in 5d08c9c579ba8cc7b684105c6a08263992b08d52.

ACKs for top commit:
  ariard:
    ACK 9075d13, changes since last reviewed are splitting them in separate commits to ease understanding and fix nits
  fjahr:
    ACK 9075d13153ce06cd59a45644831ecc43126e1e82, confirmed diff to last review was fixing nits in docs/comments.
  ryanofsky:
    Code review ACK 9075d13153ce06cd59a45644831ecc43126e1e82. Only changes since last review are splitting the main commit and updating comments

Tree-SHA512: 58e8a1a4d4e6f156da5d29fb6ad6a62fc9c594bbfc6432b3252e962d0e9e10149bf3035185dc5320c46c09f3e49662bc2973ec759679c0f3412232087cb8a3a7

1 files changed, 19 insertions, 0 deletions

diff --git a/doc/release-notes-15437.md b/doc/release-notes-15437.md
index 031e90ccd2..6614207757 100644
--- a/doc/release-notes-15437.md
+++ b/doc/release-notes-15437.md
@@ -32,3 +32,22 @@ Please use the recommended alternatives if you rely on this deprecated feature:
   could wait until the transaction has confirmed (taking into account the fee
   target they set (compare the RPC `estimatesmartfee`)) or listen for the
   transaction announcement by other network peers to check for propagation.
+
+The removal of BIP61 REJECT message support also has the following minor RPC
+and logging implications:
+
+* `testmempoolaccept` and `sendrawtransaction` no longer return the P2P REJECT
+  code when a transaction is not accepted to the mempool. They still return the
+  verbal reject reason.
+
+* Log messages that previously reported the REJECT code when a transaction was
+  not accepted to the mempool now no longer report the REJECT code. The reason
+  for rejection is still reported.
+
+Updated RPCs
+------------
+
+- `testmempoolaccept` and `sendrawtransaction` no longer return the P2P REJECT
+  code when a transaction is not accepted to the mempool. See the Section
+  _Removal of reject network messages from Bitcoin Core (BIP61)_ for details on
+  the removal of BIP61 REJECT message support.