When a transaction is being checked for acceptance into the transation
memory pool, it makes use of a chain function to ensure the invariant rules
for what transactions are allowed into a block are not violated. That
function returns a btcchain.RuleError if rules are violated. However,
since this code path is tailored to free-standing transactions, the error
needs to be converted to a TxRuleError so the caller can properly detect
the transaction as a rejected transaction instead of treating it like an
real error.
This commit modifies the transaction memory pool handling so that it does
not relay resurrected transactions. The other peers on the network will
also be reorganizing to the same block, so they already know about them.
This commit adds a few more checks to restrict what transactions are
allowed into the transaction memory pool and therefore are candidates
to be mined and relayed.
In particular, the following changes were made to what is considered
standard:
- nulldata scripts are now supported and considered standard
- multi-signature transaction are now checked to ensure they only have a
max of 3 pubkeys and the number of signatures doesn't exceed the number
of pubkeys
- the number of inputs to a signature script must now match the expected
number of inputs for the script type (includes support for additional
pay-to-script-hash inputs)
- the number of inputs pushed onto the stack by a redeeming sig script
must match the number of inputs consumed by the referenced pk script
- there can now only be a max of one nulldata output per transaction
This commit changes the various cases that were serializing transactions
into a buffer and taking the length to use the new faster SerializeSize
API. It also completes a TODO since the serialized size of a transaction
output is now available.
This commit updates btcd to work with the new btcchain APIs which now
accept btcutil.Tx instead of raw btcwire.MsgTx. It also modifies the
transaction memory pool to store btcutil.Tx.
This is part of the ongoing transaction hash optimization effort noted in
conformal/btcd#25.
The ValidateTransactionScripts was recently changed to accept script flags
which pass through to the script engine in order to control its validation
behavior. This commit modifies the transaction memory pool script
validation code for this change and additionally adds the new flag to
perform canonical signtaure checking.
It was previously possible for the unprotected iteration of the mempool
orphans to lead to undefined results. This commit remedies that by
reworking the locking code a bit. It also embeds the mutex directly into
the mempool struct rather than having a separate field for it so the
syntax is a slightly cleaner.
This commit adds code to properly respond to getdata requests for
transactions by fetching them from the transaction pool. Previously, we
advertised newly available transactions, but the code to respond with the
actual transaction was not written yet.
Also, fix a couple of comments and make the pushTxMsg and pushBlockMsg
functions consistent.
This commit is a first pass at improving the logging. It changes a number
of things to improve the readability of the output. The biggest addition
is message summaries for each message type when using the debug logging
level.
There is sitll more to do here such as allowing the level of each
subsystem to be independently specified, syslog support, and allowing the
logging level to be changed run-time.
The block manager handles inventory messges to know which inventory should
be requested based on what is already known and what is already in flight.
So, this commit adds logic to ask the transaction memory pool if the
transaction is already known before requesting it and tracks pending
requests into an in-flight transaction map owned by the block manager.
It also moves the transaction processing into the block manager so the
in-flight map can be properly cleaned.
Also, the loops which only remove a single element and break or return
don't need the extra logic for iteration since they don't continue
iteration after removal.
It is not safe to remove an item from a container/list while iterating the
list without first saving the next pointer since removing the item nils
the internal list element's next pointer.
This commit is a rather large one which implements transaction pool and
relay according to the protocol rules of the reference implementation.
It makes use of btcchain to ensure the transactions are valid for the
block chain and includes several stricter checks which determine if they
are "standard" or not before admitting them into the pool and relaying
them.
There are still a few TODOs around the more strict rules which determine
which transactions are willing to be mined, but the core checks which
are imperative (everything except the all of the "standard" checks really)
to operate as a good citizen on the bitcoin network are in place.
