The main effect is to exit processing for recently-rejected hashes,
in case they are pushed to us without prior advertisement. This
behavior was seen in the wild.
An additional effect is to do early checks for mempool or mapOrphan
existence. No logging or nDoS tracking is needed for failures of
these checks.
In txn_clone.py, non-essential test transaction tx2 was asserted
to be unconfirmed, but would occasionally confirm depending on
network behavior. Fix by explicitly sharing with miner and
checking for 1 confirmation.
Reduce required conflict tests from 4 to 2, by moving one invocation
each of txn_clone.py and txn_doublespend.py to the extented test
section. This saves about 15 seconds per test run for me.
Chance "getbalance *" not to use IsTrusted. The method and result
now match the "getbalance <specific-account>" behavior. In
particular, "getbalance * 0" now works.
Also fixed a comment -- GetGalance has required 1 confirmation
for many years, and the default "getbalance *" behavior matches
that.
Does what the old txnmall.sh test did.
Creates an equivalent malleated clone and tests that SyncMetaData
syncs the accounting effects from the original transaction to the
confirmed clone.
Remove reliance on accounting "move" ledger entries. Instead,
create funding transactions (and deal with fee complexities).
Do not rely on broken SyncMetaData. Instead expect double-spend
amount to be debited from the default "" account.
Define CTransaction::IsEquivalentTo(const CTransaction& tx)
True if only scriptSigs are different. In other words, true if
the two transactions are malleability clones. In other words,
true if the two transactions have the same effect on the
outside universe.
In the wallet, only SyncMetaData for equivalent transactions.
The regtest framework is local, so often there is no need to
discover our external IP. Setting -discover=0 in util.py works
around shutdown hang caused by GetExternalIP waiting in recv().
-respendnotify=<cmd> Execute command when a network tx respends wallet
tx input (%s=respend TxID, %t=wallet TxID)
Add respendsobserved array to gettransaction, listtransactions, and
listsinceblock RPCs. This omits the malleated clones that are included
in the walletconflicts array.
Add RPC help for respendsobserved and walletconflicts (help was missing
for the latter).
Respend transactions that conflict with transactions already in the
wallet are added to it. They are not displayed unless they also involve
the wallet, or get into a block. If they do not involve the wallet,
they continue not to affect balance.
Transactions that involve the wallet, and have conflicting non-equivalent
transactions, are highlighted in red. When the conflict first occurs, a
modal dialog is thrown.
CWallet::SyncMetaData is changed to sync only to equivalent transactions.
When a conflict is added to the wallet, counter nConflictsReceived is
incremented. This acts like a change in active block height for the
purpose of triggering UI updates.
Allows network wallets and other clients to see transactions that respend
a prevout already spent in an unconfirmed transaction in this node's mempool.
Knowledge of an attempted double-spend is of interest to recipients of the
first spend. In some cases, it will allow these recipients to withhold
goods or services upon being alerted of a double-spend that deprives them
of payment.
As before, respends are not added to the mempool.
Anti-Denial-of-Service-Attack provisions:
- Use a bloom filter to relay only one respend per mempool prevout
- Rate-limit respend relays to a default of 100 thousand bytes/minute
- Define tx2.IsEquivalentTo(tx1): equality when scriptSigs are not considered
- Do not relay these equivalent transactions
Remove an unused variable declaration in txmempool.cpp.
Tom Harding