Introduce an ECDSA signature verification into btcd in order to
mitigate a certain DoS attack and as a performance optimization.
The benefits of SigCache are two fold. Firstly, usage of SigCache
mitigates a DoS attack wherein an attacker causes a victim's client to
hang due to worst-case behavior triggered while processing attacker
crafted invalid transactions. A detailed description of the mitigated
DoS attack can be found here: https://bitslog.wordpress.com/2013/01/23/fixed-bitcoin-vulnerability-explanation-why-the-signature-cache-is-a-dos-protection/
Secondly, usage of the SigCache introduces a signature verification
optimization which speeds up the validation of transactions within a
block, if they've already been seen and verified within the mempool.
The server itself manages the sigCache instance. The blockManager and
txMempool respectively now receive pointers to the created sigCache
instance. All read (sig triplet existence) operations on the sigCache
will not block unless a separate goroutine is adding an entry (writing)
to the sigCache. GetBlockTemplate generation now also utilizes the
sigCache in order to avoid unnecessarily double checking signatures
when generating a template after previously accepting a txn to the
mempool. Consequently, the CPU miner now also employs the same
optimization.
The maximum number of entries for the sigCache has been introduced as a
config parameter in order to allow users to configure the amount of
memory consumed by this new additional caching.
This commit converts all block height references to int32 instead of
int64. The current target block production rate is 10 mins per block
which means it will take roughly 40,800 years to reach the maximum
height an int32 affords. Even if the target rate were lowered to one
block per minute, it would still take roughly another 4,080 years to
reach the maximum.
In the mean time, there is no reason to use a larger type which results
in higher memory and disk space usage. However, for now, in order to
avoid having to reserialize a bunch of database information, the heights
are still serialized to the database as 8-byte uint64s.
This is being mainly being done in preparation for further upcoming
infrastructure changes which will use the smaller and more efficient
4-byte serialization in the database as well.
IsUnspendable takes a public key script and returns whether it is
spendable.
Additionally, hook this into the mempool isDust function, since
unspendable outputs can't be spent.
This mimics Bitcoin Core commit 0aad1f13b2430165062bf9436036c1222a8724da
This change moves IsFinalizedTransaction to txscript and also changes
the first argument to take a wire.MsgTx instead of btcutil.Tx. This
is needed for an upcoming diff in which txscript will require
IsFinalizedTransaction and we do not want to import the btcd/blockchain.
The option -maxorphantx allows the user to specify the number of
orphan transactions to keep in memory.
Also, lower the default max orphan count from 10000 to 1000.
Fix#303 by changing the addrindex key prefix to 3 characters so that
it's easy to check length when dropping the index. To drop the old
index, check to make sure we aren't dropping any entries that end in
"sx" or "tx" as those aren't part of the addrindex. Update test to
deal with the new prefix length.
Fix#346 by changing the pointers in the mempool's addrindex map to
wire.ShaHash 32-byte values. This lets them be deleted even if the
transaction data changes places in memory upon expanding the maps.
Change the way addrindex uint32s are stored to big-endian in order to
sort the transactions on disk in chronological/dependency order.
Change the "searchrawtransactions" RPC call to return transactions
from the database before the memory pool so that they're returned in
order. This commit DOES NOT do topological sorting of the memory pool
transactions to ensure they're returned in dependency order. This may
be a good idea for a future enhancement.
Add addrindex versioning to automatically drop the old/incompatible
version of the index and rebuild with the new sort method and key
prefix.
For every transaction in a newly accepted block, process the orphan
pool moving now no longer orphan transactions to the mempool.
Previously, no longer orphan transactions would remain in the orphan
pool.
This commit modifies finalized transaction check used by the memory pool
and block templates to use the network adjusted time instead of the
unadjusted local time. This helps keep the transactions accepted to the
memory pool, and hence allowed to relay, more consistent across nodes.
By exporting StandardVerifyFlags, clients can ensure they create
transactions that btcd will accept into its mempool.
This flag doesn't belong in txscript. It belongs in a
policy package. However, this is currently the least worse place.
This modifies the recently added code which rejects free/low-fee
transactions with insufficient priority to ignore resurrected transactions
from disconnected blocks. It also exempts resurrected transactions from
the free/low-fee rate limiting.
By default, have the mempool reject free and low-fee transactions that
have insufficient priority to be mined in the next block.
Addtionally, add a new configuration option, -norelaypriority, to
disable the check.
* Address index is built up concurrently with the `--addrindex` flag.
* Entire index can be deleted with `--dropaddrindex`.
* New RPC call: `searchrawtransaction`
* Returns all transacitons related to a particular address
* Includes mempool transactions
* Requires `--addrindex` to be activated and fully caught up.
* New `blockLogger` struct has been added to factor our common logging
code
* Wiki and docs updated with new features.
* When an inv is to be sent to the server for relaying, the sender
already has access to the underlying data. So
instead of requiring the relay to look up the data by
hash, the data is now coupled in the request message.
The mempool's MaybeAcceptTransaction methods have also been modified
to return a slice of transaction hashes referenced by the transaction
inputs which are unknown (totally spent or never seen). While this is
currently used to include the first hash in a ProcessTransaction error
message if inserting orphans is not allowed, it may also be used in
the future to request orphan transactions from peers.
This commit addresses a few nitpicks in the recent getrawmppol update
which populates the starting and current priority fields.
In particular:
- Move the new calcInputValueAge function before the function which
invokes it so it is consistent with the rest of the mempool code
- Double space after periods for consistency
- Correct the comments for calcInputValueAge to indiciate that inputs
which are in the the memory pool count as zero toward the value age
rather than the incorrect claim that that the overal input value age is
zero when one of them does
- Rename endingPriority to currentPriority to match the RPC field and its
actual function
- Make the comment about using zero when input transactions can't be found
for some reason more accurate since there can be (and frequently is)
more than one input transaction
This change removes transactions from a newly connected block
from the orphan pool if they exist. Additionally, any orphan
transactions that are no longer orphan transactions are moved
to the mempool and inv'd to the currently connected peers.
This commit builds on the recent limiter updates. The recent changes
introduced a new function named calcTxFee which could easily be confused
with calculating the fees of the transaction rather than its intended
purpose of calculating the minimum transaciton relay fee.
Rather than taking that approach, this commit instead renames the existing
function to calcMinRequiredTxRelayFee and uses a consistent variable name
for the serialized size of a transaction. It then moves the check for
whether or not the check should be applied based on the serialized size of
the transcation and block priority to the call site.
This approach also has the benefit of avoiding two calls to the
calculation function since it's a local at the call site.
ok @jrick, @dajohi
Before, btcd was rate limiting all transactions that had a minimum
fee of zero. Now, btcd only rate limits transactions that contain
a fee less than the calculated fee based on size.
Closes#163
This commit implements reject handling as defined by BIP0061 and bumps the
maximum supported protocol version to 70002 accordingly.
As a part of supporting this a new error type named RuleError has been
introduced which encapsulates and underlying error which could be one of
the existing TxRuleError or btcchain.RuleError types.
This allows a single high level type assertion to be used to determine if
the block or transaction was rejected due to a rule error or due to an
unexpected error. Meanwhile, an appropriate reject error can be created
from the error by pulling the underlying error out and using it.
Also, a check for minimum protocol version of 209 has been added.
Closes#133.
This commit implements the long polling portion of the getblocktemplate
RPC as defined by BIP0022. Per the specification, each block template is
returned with a longpollid which can be used in a subsequent
getblocktemplate request to keep the connection open until the server
determines the block template associated with the longpollid should be
replaced with a new one.
This is work towards #124.
This commit helps prevent transaction malleability by enforcing that the
extra dummy value on multisig transaction script contains no data for a
transaction . This syncs with a recent change in Bitcoin Core to remain
compatible.
As part of this change a new constant has been introduced which is used to
specify the script flags which are used for standard transactions. This
constant is then used in both the memory pool and the mining code to
ensure they remain in sync with one another.
Closes#131.
ok @jrick, @dajohi
This commit raises the maximum allowed size for a standard signature
script to cover a 15-of-15 multi-signature pay-to-script-hash with
compressed pubkeys.
This mirrors a recent change to remain compatible with Bitcoin Core.
ok @owinga who also helped verify and correct the script math.
Closes#128.
This change modifies the params struct to embed a *btcnet.Params,
removing the old parameter fields that are handled by the btcnet
package.
Hardcoded network checks have also been removed in favor of modifying
behavior based on the current active net's parameters.
Not all library packages, notable btcutil and btcchain, have been
updated to use btcnet yet, but with this change, each package can be
updated one at a time since the active net's btcnet.Params are
available at each callsite.
ok @davecgh
