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.
PushedData returns an array of byte slices containing any pushed data
found in the passed script. This includes OP_0, but not OP_1 - OP_16.
help from and ok @owainga
This commit corrects the number of expected inputs for a multi-sig script
to include the additional item that is popped from the stack due to the
OP_CHECKMULTISIG consensus bug (which is required and properly performed).
Note this issue did NOT affect the consensus critical code and hence would
not cause a chain fork. It did however, cause standard p2sh multisig txns
to be rejected from the mempool as nonstandard.
The tx rejected as non-standard which prompted this was spotted by
@mbelshe on IRC.
ok @owainga
Also, unexport the functions to generate script types. Everything should
(and is) be using PayToAddrScript() with an address type instead of
throwing bytes around.
discussed with #@davecgh
This removes the bip16 bool from NewScript and adds it to flags (with
the constant ScriptBip16), and also adds a new flag,
ScriptCanonicalSignatures, which will call btcec.ParseDERSignature
parsing a signature during an Execute. This is needed to emulate
bitcoind behavior, as bitcoind performs canonical signature validation
(DER format) in some places (like mempool acceptance) but not others
(like block validation).
Updated tests and test coverage file to reflect changes.
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.
This commit modifies the code to no longer require a protocol version. It
does this by making use of the new Serialize function in btcwire.
Unfortuantely this does entail a public API change which I generally don't
like to do, but eliminating the usage of the protocol version throughout
the codebase was important enough to warrant the change.
