So we stop getting pull requests (like #2604) fixing problems with disabled Script opcodes.
A hard fork would be required to re-enable these, and if we ever did that we'd require extensive review and testing.
Since block validation happens in parallel, multiple threads may be
accessing the signature cache simultaneously. To prevent contention:
* Turn the signature cache lock into a shared mutex
* Make reading from the cache only acquire a shared lock
* Let block validations not store their results in the cache
These flags select features to be enabled/disabled during script
evaluation/checking, instead of several booleans passed along.
Currently these flags are defined:
* SCRIPT_VERIFY_P2SH: enable BIP16-style subscript evaluation
* SCRIPT_VERIFY_STRICTENC: enforce strict adherence to pubkey/sig encoding standards.
This switches bitcoin's transaction/block verification logic to use a
"coin database", which contains all unredeemed transaction output scripts,
amounts and heights.
The name ultraprune comes from the fact that instead of a full transaction
index, we only (need to) keep an index with unspent outputs. For now, the
blocks themselves are kept as usual, although they are only necessary for
serving, rescanning and reorganizing.
The basic datastructures are CCoins (representing the coins of a single
transaction), and CCoinsView (representing a state of the coins database).
There are several implementations for CCoinsView. A dummy, one backed by
the coins database (coins.dat), one backed by the memory pool, and one
that adds a cache on top of it. FetchInputs, ConnectInputs, ConnectBlock,
DisconnectBlock, ... now operate on a generic CCoinsView.
The block switching logic now builds a single cached CCoinsView with
changes to be committed to the database before any changes are made.
This means no uncommitted changes are ever read from the database, and
should ease the transition to another database layer which does not
support transactions (but does support atomic writes), like LevelDB.
For the getrawtransaction() RPC call, access to a txid-to-disk index
would be preferable. As this index is not necessary or even useful
for any other part of the implementation, it is not provided. Instead,
getrawtransaction() uses the coin database to find the block height,
and then scans that block to find the requested transaction. This is
slow, but should suffice for debug purposes.
Special serializers for script which detect common cases and encode
them much more efficiently. 3 special cases are defined:
* Pay to pubkey hash (encoded as 21 bytes)
* Pay to script hash (encoded as 21 bytes)
* Pay to pubkey starting with 0x02, 0x03 or 0x04 (encoded as 33 bytes)
Other scripts up to 121 bytes require 1 byte + script length. Above
that, scripts up to 16505 bytes require 2 bytes + script length.
Due to a bug in the implementation of MakeSameSize(), using OP_AND, OP_OR, or OP_XOR with signed values of unequal size will result in the sign-value becoming part of the smaller integer, with nonsensical results. This patch documents the unexpected behavior and provides the basis of a solution should decision be made to fix the bug in the future.
Implement listunspent / getrawtransaction / createrawtransaction /
signrawtransaction, to support creation and
signing-on-multiple-device multisignature transactions.
This introduces internal types:
* CKeyID: reference (hash160) of a key
* CScriptID: reference (hash160) of a script
* CTxDestination: a boost::variant of the former two
CBitcoinAddress is retrofitted to be a Base58 encoding of a
CTxDestination. This allows all internal code to only use the
internal types, and only have RPC and GUI depend on the base58 code.
Furthermore, the header dependencies are a lot saner now. base58.h is
at the top (right below rpc and gui) instead of at the bottom. For the
rest: wallet -> script -> keystore -> key. Only keystore still requires
a forward declaration of CScript. Solving that would require splitting
script into two layers.
More than doubles the speed of verifying already-cached signatures
that use compressed pubkeys:
Before: ~200 microseconds
After: ~80 microseconds
(no caching at all: ~3,300 microseconds per signature)
Also encapsulates the signature cache code in a class
and fixes a signed/unsigned comparison warning.
C++ STL ::size() generally returns unsigned, which implies that "int idx"
style of loop variable will generate a signed-vs-unsigned comparison warning
when testing the loop exit condition "idx < blah.size()"
Update areas of the bitcoin code where loop variables may be more properly and
correctly defined as unsigned.
This commit removes the dependency of serialize.h on PROTOCOL_VERSION,
and makes this parameter required instead of implicit. This is much saner,
as it makes the places where changing a version number can have an
influence obvious.
so it takes a flag for how to interpret OP_EVAL.
Also increased IsStandard size of scriptSigs to 500 bytes, so
a 3-of-3 multisig transaction IsStandard.
OP_EVAL is a new opcode that evaluates an item on the stack as a script.
It enables a new type of bitcoin address that needs an arbitrarily
complex script to redeem.
