BIP0062 defines specific rules and canonical encodings for data pushes.
The existing script builder code already conformed to all but one of the
canonical data push rules that was added after it was originally
implemented (adding a single byte of 0x81 must be converted to
OP_1NEGATE). This commit implements that case and expands the existing
tests to explicitly cover all cases mentioned in BIP0062.
In addition, as a part of this change, the AddData function has been
modified so that any attempt to push more than the maximum script element
size bytes (520) in one push or any pushes the would cause the script to
exceed the maximum script bytes allowed by the script engine (10000) will
result in the final call to the Script function to only return the script
up to the point of the first error along with the error. This change
should have little effect on existing callers since they are almost
positively not creating scripts which violate these rules as they could
never be executed, however it does mean they need to check the new error
return.
Since the regression tests intentionally need to be able to exceed that
limit, a new function named AddFullData has been added which does not
enforce the limits, but still provides canonical encoding of the pushed
data.
Note that this commit does not affect consensus rules nor modify the
script engine.
Also, the tests have been marked so they can run in parallel.
Both the script tests (positive and negative) and tx texts (ditto) are
present. Some of the tx tests in the negative section have been
replaced by a comment line explaining why that test is elided, to add in
diffing. The reasons were always that they test things handled by other
parts of the btcd stack (normally chain). For example MAX_MONEY, number
of outputs, coinbase sizes etc.
Much of the inital test logic from @dajohi using hand transcribed tables
for selected tests. The json parsers, script format parser and a lot of
cleaning up/bugfixing from your truly. @davecgh had some input too.
This commit significantly changes the address extraction code. The
original code was written before some of the other newer code was written
and as a result essentially duplicated some of the logic for handling
standard scripts which is used elsewhere in the package.
The following is a summary of what has changed:
- CalcPkScriptAddrHashes, ScriptToAddrHash, and ScriptToAddrHashes have
been replaced by ExtractPkScriptAddresses
- The ScriptType type has been removed in favor of the existing
ScriptClass type
- The new function returns a slice of btcutil.Addresses instead of raw
hashes that the caller then needs to figure out what to do with to
convert them to proper addressses
- The new function makes use of the existing ScriptClass instead of an
nearly duplicate ScriptType
- The new function hooks into the existing infrastructure for parsing
scripts and identifying scripts of standard forms
- The new function only works with pkscripts to match the behavior of the
reference implementation - do note that the redeeming script from a p2sh
script is still considered a pkscript
- The logic combines extraction for all script types instead of using a
separate function for multi-signature transactions
- The new function ignores addresses which are invalid for some reason
such as invalid public keys
So add entries for them that disassemble and parse ok, but will fail
when executed with the appropriate error. Add a full suite of tests to confirm
that this happens.
Found by a strange transaction in testnet.
PayToPubKeyHashScript generates a new pay to pubkey hash script to use
as the pkScript when creating new transactions. If the passed pubkey
hash is an invalid size, StackErrInvalidOpcode will be returned as an
error.
SignatureScript returns the signature script necessary to validate a
single input of a transaction.
This also adds sanity checking for serializing scripts into byte
slices. If the length of a serialized opcode does not equal the
expected length, StackErrInvalidOpcode will be returned when unparsing
a []parsedOpcode.
New internal tests were added to verify checks for valid and invalid
parsed opcodes.
