1e747e3c1e Make segwit failure due to CLEANSTACK violation return a SCRIPT_ERR_CLEANSTACK error code. (Mark Friedenbach)
Pull request description:
If a segwit script terminates with a stack size not equal to one, the current error code is EVAL_FALSE. This is semantically wrong, and prevents explicitly checking CLEANSTACK violations in the unit tests. This PR changes the error code (and affected unit tests) to use SCRIPT_ERROR_CLEANSTACK instead of SCRIPT_ERROR_EVAL_FALSE.
Tree-SHA512: 8f7b1650f7a23a942cde1070e3e56420be456b4a7be42515b237e95557bf2bd5e7ba9aabd213c8092bea28c165dbe73f5a3486300089aeb01e698151b42484b1
f8c249ab91 Assert CPubKey::ValidLength to the pubkey's header-relevent size (Ben Woosley)
Pull request description:
A pubkey's length is specific to its type which is indicated by its header value. GetLen returns the header-indicated length, so this change ensures that a key matches its header-indicated length.
And replace some magic values with their constant equivalents.
Tree-SHA512: b727b39a631babe0932326396fc4d796ade8ec1e37454ff0c709ae9b78ecbd0cfdf59d84089ba8415e6efa7bc180e3cd39a14ddaf0871cbac54b96851e1b7b44
d40f06a Introduce interface for signing providers (Pieter Wuille)
Pull request description:
`CKeyStore` is a rich interface that provides many features, including knowledge of scripts and pubkeys for solving, private keys for signing, in addition to watch-only keys and scripts, and distinguishing lack of keys from them just being encrypted.
The signing logic in script/sign does not actually need most of these features. Here we introduce a simpler interface (`SigningProvider`) which *only* provides keys and scripts. This is actually sufficient for signing.
In addtion, we swap the dependency between keystore and script/sign (keystore now depends on script/script with `CKeyStore` deriving from `SigningProvider`, rather than `CKeyStore` being the interface that signing relies on).
This is a very early step towards the design in https://gist.github.com/sipa/125cfa1615946d0c3f3eec2ad7f250a2, separating the concern between deciding what outputs are ours and signing.
Tree-SHA512: d511b7b03eec0e513530db1d9ae5aacf6d0bfa1d3e1c03d06c5bde396bafb5824c4491b227d32bcda9288530caf49835da18e846ccf66538d6c0cc6ae27291c9
1f45e21 scripted-diff: Convert 11 enums into scoped enums (C++11) (practicalswift)
Pull request description:
Rationale (from Bjarne Stroustrup's ["C++11 FAQ"](http://www.stroustrup.com/C++11FAQ.html#enum)):
>
> The enum classes ("new enums", "strong enums") address three problems with traditional C++ enumerations:
>
> * conventional enums implicitly convert to int, causing errors when someone does not want an enumeration to act as an integer.
> * conventional enums export their enumerators to the surrounding scope, causing name clashes.
> * the underlying type of an enum cannot be specified, causing confusion, compatibility problems, and makes forward declaration impossible.
>
> The new enums are "enum class" because they combine aspects of traditional enumerations (names values) with aspects of classes (scoped members and absence of conversions).
Tree-SHA512: 9656e1cf4c3cabd4378c7a38d0c2eaf79e4a54d204a3c5762330840e55ee7e141e188a3efb2b4daf0ef3110bbaff80d8b9253abf2a9b015cdc4d60b49ac2b914
CKeyStore is a rich interface that provides many features, including knowledge
of scripts and pubkeys for solving, private keys for signing, in addition to
watch-only keys and scripts, and distinguishing lack of keys from them just
being encrypted.
The signing logic in script/sign does not actually need most of these features.
Here we introduce a simpler interface (SigningProvider) which *only* provides
keys and scripts. This is actually sufficient for signing.
In addtion, we swap the dependency between keystore and script/sign
(keystore now depends on script/script with CKeyStore deriving from
SigningProvider, rather than CKeyStore being the interface that signing
relies on).
This adds a READWRITEAS(type, obj) macro which serializes obj as if it
were casted to (const type&) when const, and to (type&) when non-const.
This makes it usable in serialization code that uses a single
implementation for both serialization and deserializing, which doesn't
know the constness of the object involved.
172f5fa738 Support deserializing into temporaries (Pieter Wuille)
2761bca997 Merge READWRITEMANY into READWRITE (Pieter Wuille)
Pull request description:
This is another fragment of improvements from #10785.
The current serialization code does not support serializing/deserializing from/to temporaries (like `s >> CFlatData(script)`). As a result, there are many invocations of the `REF` macro which in addition to changing the reference type also changes the constness. This is unnecessary in C++11 as we can use rvalue references now instead.
The first commit is an extra simplification we can make that removes the duplication of code between `READWRITE` and `READWRITEMANY` (and related functions).
Tree-SHA512: babfa9cb268cc3bc39917e4f0a90e4651c33d85032161e16547a07f3b257b7ca7940e0cbfd69f09439d26fafbb1a6cf6359101043407e2c7aeececf7f20b6eed
Currently, the READWRITE macro cannot be passed any non-const temporaries, as
the SerReadWrite function only accepts lvalue references.
Deserializing into a temporary is very common, however. See for example
things like 's >> VARINT(n)'. The VARINT macro produces a temporary wrapper
that holds a reference to n.
Fix this by accepting non-const rvalue references instead of lvalue references.
We don't propagate the rvalue-ness down, as there are no useful optimizations
that only apply to temporaries.
Then use this new functionality to get rid of many (but not all) uses of the
'REF' macro (which casts away constness).
0749808a7 CheckMinimalPush comments are prescriptive (Gregory Sanders)
176db6147 simplify CheckMinimalPush checks, add safety assert (Gregory Sanders)
Pull request description:
the two conditions could simply never be hit as `true`, as those opcodes have a push payload of size 0 in `data`.
Added the assert for clarity for future readers(matching the gating in the interpreter) and safety for future use.
This effects policy only.
Tree-SHA512: f49028a1d5e907ef697b9bf5104c81ba8f6a331dbe5d60d8d8515ac17d2d6bfdc9dcc856a7e3dbd54814871b7d0695584d28da6553e2d9d7715430223f0b3690
9360f5032 Drop extra script variable in ProduceSignature (Russell Yanofsky)
Pull request description:
Was slightly confusing.
Tree-SHA512: 1d18f92c133772ffc8eb71826c8d778988839a14bcefc50f9c591111b0a5f81ebc12bca0f1ab25d5fdd02d3d50c2325c04cbfcbdcd18a7b80ca112d049c2327d
Previously this was an inline test where the specificity was probably judged
overly specific. As a class method it makes sense to maintain consistency.
And replace some magic values with their constant equivalents.
5bdbbdc Refactor HaveKeys to early return on false result (João Barbosa)
Pull request description:
This consists in a trivial change where the return type of `HaveKeys()` is now `bool` meaning that it returns whether all keys are in the keystore, and early returns when one isn't.
Tree-SHA512: 03e35ea8486404b84884b49f6905c9f4fc161a3eeef080b06482d77985d5242a2bdd57a34b8d16abe19ee8c6cfa3e6fbcb935c73197d53f4cd468a2c7c0b889b
9ad6746ccd Use static_cast instead of C-style casts for non-fundamental types (practicalswift)
Pull request description:
A C-style cast is equivalent to try casting in the following order:
1. `const_cast(...)`
2. `static_cast(...)`
3. `const_cast(static_cast(...))`
4. `reinterpret_cast(...)`
5. `const_cast(reinterpret_cast(...))`
By using `static_cast<T>(...)` explicitly we avoid the possibility of an unintentional and dangerous `reinterpret_cast`. Furthermore `static_cast<T>(...)` allows for easier grepping of casts.
For a more thorough discussion, see ["ES.49: If you must use a cast, use a named cast"](https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#es49-if-you-must-use-a-cast-use-a-named-cast) in the C++ Core Guidelines (Stroustrup & Sutter).
Tree-SHA512: bd6349b7ea157da93a47b8cf238932af5dff84731374ccfd69b9f732fabdad1f9b1cdfca67497040f14eaa85346391404f4c0495e22c467f26ca883cd2de4d3c
b224a47a1 Add address_types test (Pieter Wuille)
7ee54fd7c Support downgrading after recovered keypool witness keys (Pieter Wuille)
940a21932 SegWit wallet support (Pieter Wuille)
f37c64e47 Implicitly know about P2WPKH redeemscripts (Pieter Wuille)
57273f2b3 [test] Serialize CTransaction with witness by default (Pieter Wuille)
cf2c0b6f5 Support P2WPKH and P2SH-P2WPKH in dumpprivkey (Pieter Wuille)
37c03d3e0 Support P2WPKH addresses in create/addmultisig (Pieter Wuille)
3eaa003c8 Extend validateaddress information for P2SH-embedded witness (Pieter Wuille)
30a27dc5b Expose method to find key for a single-key destination (Pieter Wuille)
985c79552 Improve witness destination types and use them more (Pieter Wuille)
cbe197470 [refactor] GetAccount{PubKey,Address} -> GetAccountDestination (Pieter Wuille)
0c8ea6380 Abstract out IsSolvable from Witnessifier (Pieter Wuille)
Pull request description:
This implements a minimum viable implementation of SegWit wallet support, based on top of #11389, and includes part of the functionality from #11089.
Two new configuration options are added:
* `-addresstype`, with options `legacy`, `p2sh`, and `bech32`. It controls what kind of addresses are produced by `getnewaddress`, `getaccountaddress`, and `createmultisigaddress`.
* `-changetype`, with the same options, and by default equal to `-addresstype`, that controls what kind of change is used.
All wallet private and public keys can be used for any type of address. Support for address types dependent on different derivation paths will need a major overhaul of how our internal detection of outputs work. I expect that that will happen for a next major version.
The above also applies to imported keys, as having a distinction there but not for normal operations is a disaster for testing, and probably for comprehension of users. This has some ugly effects, like needing to associate the provided label to `importprivkey` with each style address for the corresponding key.
To deal with witness outputs requiring a corresponding redeemscript in wallet, three approaches are used:
* All SegWit addresses created through `getnewaddress` or multisig RPCs explicitly get their redeemscripts added to the wallet file. This means that downgrading after creating a witness address will work, as long as the wallet file is up to date.
* All SegWit keys in the wallet get an _implicit_ redeemscript added, without it being written to the file. This means recovery of an old backup will work, as long as you use new software.
* All keypool keys that are seen used in transactions explicitly get their redeemscripts added to the wallet files. This means that downgrading after recovering from a backup that includes a witness address will work.
These approaches correspond to solutions 3a, 1a, and 5a respectively from https://gist.github.com/sipa/125cfa1615946d0c3f3eec2ad7f250a2. As argued there, there is no full solution for dealing with the case where you both downgrade and restore a backup, so that's also not implemented.
`dumpwallet`, `importwallet`, `importmulti`, `signmessage` and `verifymessage` don't work with SegWit addresses yet. They're remaining TODOs, for this PR or a follow-up. Because of that, several tests unexpectedly run with `-addresstype=legacy` for now.
Tree-SHA512: d425dbe517c0422061ab8dacdc3a6ae47da071450932ed992c79559d922dff7b2574a31a8c94feccd3761c1dffb6422c50055e6dca8e3cf94a169bc95e39e959
This adds new fields 'pubkeys' and 'embedded' to the RPC's output, and improves the
documentation for previously added 'witness_version' and 'witness_program' fields.
a720b92 Remove includes in .cpp files for things the corresponding .h file already included (practicalswift)
Pull request description:
Remove includes in .cpp files for things the corresponding .h file already included.
Example case:
* `addrdb.cpp` includes `addrdb.h` and `fs.h`
* `addrdb.h` includes `fs.h`
Then remove the direct inclusion of `fs.h` in `addrman.cpp` and rely on the indirect inclusion of `fs.h` via the included `addrdb.h`.
In line with the header include guideline (see #10575).
Tree-SHA512: 8704b9de3011a4c234db336a39f7d2c139e741cf0f7aef08a5d3e05197e1e18286b863fdab25ae9638af4ff86b3d52e5cab9eed66bfa2476063aa5c79f9b0346
01013f5 Simplify tx validation tests (Pieter Wuille)
2dd6f80 Add a test that all flags are softforks (Pieter Wuille)
2851b77 Make all script verification flags softforks (Pieter Wuille)
Pull request description:
This change makes `SCRIPT_VERIFY_UPGRADABLE_NOPS` not apply to `OP_CHECKLOCKTIMEVERIFY` and `OP_CHECKSEQUENCEVERIFY`. This is a no-op as `UPGRADABLE_NOPS` is only set for mempool transactions, and those always have `SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY` and `SCRIPT_VERIFY_CHECKSEQUENCEVERIFY` set as well. The advantage is that setting more flags now always results in a reduction in acceptable scripts (=softfork).
This results in a nice and testable property for validation, for which a new test is added.
This also means that the introduction of a new definition for a NOP or witness version will likely need the following procedure (example OP_NOP8 here)
* Remove OP_NOP8 from being affected by `SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS`.
* Add a `SCRIPT_VERIFY_DISCOURAGE_NOP8`, which only applies to `OP_NOP8`.
* Add a `SCRIPT_VERIFY_NOP8` which implements the new consensus logic.
* Before activation, add `SCRIPT_VERIFY_DISCOURAGE_NOP8` to the mempool flags.
* After activation, add `SCRIPT_VERIFY_NOP8` to both the mempool and consensus flags.
Tree-SHA512: d3b4538986ecf646aac9dba13a8d89318baf9e308e258547ca3b99e7c0509747f323edac6b1fea4e87e7d3c01b71193794b41679ae4f86f6e11ed6be3fd62c72
0da49b5 Skip precompute sighash for transactions without witness (Johnson Lau)
Pull request description:
This saves unnecessary hash caching for non-segwit transactions, but I am not sure if the difference is noticeable.
Tree-SHA512: 5cd733a729a52a45781510b3572b26e76837a94155caa14311c6d23a27a12e9613ff278dfc2592e21f640202782f22c5ad00fca85c4de5efacaa617c48ccb08d
5ddf560 script: Change SignatureHash input index check to an assert. (Jim Posen)
Pull request description:
In the SignatureHash function, the input index must refer to a valid index. This is not enforced equally in the segwit/non-segwit branches and should be an assertion rather than returning a error hash.
Tree-SHA512: a775fc9e9bd9835c0ab36368aa45ab3d53e38f31fd4d2b8684a77ee6028c854c363df038681a59358b30138957573ad63b71d4a722c16e0830fb4fa72669ef39
d601f16 Fix invalid memory access in CScript::operator+= (Anthony Towns)
Pull request description:
This is a fix for #11114 -- invoking "s += s" gets turned into "s.insert(s.end(), s.begin(), s.end())" which can result in an invalid memory access is s.capacity() < 2*s.size() (because s gets resized and possibly moved, so s.begin() and s.end() become invalid references when reading the values to be appended).
The fix is straightforward: reserve enough space in advance, so that insert() doesn't need to resize and thus its arguments remain valid.
A simple test case is added as well; though you probably need to run it via valgrind to actually catch the problem when it's not fixed...
Tree-SHA512: 4720d0c17463fdc43b344c45fe603423d20b30d48da1b9d85eeedc505d7f34db1ed5495ef1556459ae962a94717e3c6e8fc441763771901efea210d01322b7ef
In the SignatureHash function, the input index must refer to a valid
index. This is not enforced equally in the segwit/non-segwit branches
and should be an assertion rather than returning a error hash.
A C-style cast is equivalent to try casting in the following order:
1. const_cast(...)
2. static_cast(...)
3. const_cast(static_cast(...))
4. reinterpret_cast(...)
5. const_cast(reinterpret_cast(...))
By using static_cast<T>(...) explicitly we avoid the possibility
of an unintentional and dangerous reinterpret_cast. Furthermore
static_cast<T>(...) allows for easier grepping of casts.
592404f03 Changing &vec[0] to vec.data(), what 9804 missed (MeshCollider)
Pull request description:
This just continues the work of https://github.com/bitcoin/bitcoin/pull/9804
Modifies a lot of `&vector[]`'s to `vector.data()`'s across all the files including tests, just the stuff that 9804 missed
Tree-SHA512: dd1a9dffb999dea4fba78dcc91fe02f90250db86f5c74948e1ff3e8b4036b2154b600555eaa04dece5368920aae3513bc36425dc96e4319ca1041b0928a6b656
This patch removes the need for the intermediary Base58 type
CBitcoinAddress, by providing {Encode,Decode,IsValid}Destination
function that directly operate on the conversion between strings
and CTxDestination.
08f71c29e [Trivial] Add a comment on the use of prevector in script. (Gregory Maxwell)
Pull request description:
Tree-SHA512: 020981516e67e576685eb9a8532178fb97d1780af409fc86d869cd05c293c0c823c26e838cf544d18610f5a3f479ce3e47d2ccb95fb1c4e55fe9e7ceb354f20b
5a9b508 [trivial] Add end of namespace comments (practicalswift)
Tree-SHA512: 92b0fcae4d1d3f4da9e97569ae84ef2d6e09625a5815cd0e5f0eb6dd2ecba9852fa85c184c5ae9de5117050330ce995e9867b451fa8cd5512169025990541a2b
This adds a new CuckooCache in validation, caching whether all of a
transaction's scripts were valid with a given set of script flags.
Unlike previous attempts at caching an entire transaction's
validity, which have nearly universally introduced consensus
failures, this only caches the validity of a transaction's
scriptSigs. As these are pure functions of the transaction and
data it commits to, this should be much safer.
This is somewhat duplicative with the sigcache, as entries in the
new cache will also have several entries in the sigcache. However,
the sigcache is kept both as ATMP relies on it and because it
prevents malleability-based DoS attacks on the new higher-level
cache. Instead, the -sigcachesize option is re-used - cutting the
sigcache size in half and using the newly freed memory for the
script execution cache.
Transactions which match the script execution cache never even have
entries in the script check thread's workqueue created.
Note that the cache is indexed only on the script execution flags
and the transaction's witness hash. While this is sufficient to
make the CScriptCheck() calls pure functions, this introduces
dependancies on the mempool calculating things such as the
PrecomputedTransactionData object, filling the CCoinsViewCache, etc
in the exact same way as ConnectBlock. I belive this is a reasonable
assumption, but should be noted carefully.
In a rather naive benchmark (reindex-chainstate up to block 284k
with cuckoocache always returning true for contains(),
-assumevalid=0 and a very large dbcache), this connected blocks
~1.7x faster.
ad1ae7a Check and enable -Wshadow by default. (Pavel Janík)
9de90bb Do not shadow variables (gcc set) (Pavel Janík)
Tree-SHA512: 9517feb423dc8ddd63896016b25324673bfbe0bffa97f22996f59d7a3fcbdc2ebf2e43ac02bc067546f54e293e9b2f2514be145f867321e9031f895c063d9fb8
- If the -maxsigcachesize parameter is set to zero, setup a minimum sized
sigcache (2 elements) rather than segfaulting.
- Handle maxsigcachesize being negative
- Handle maxsigcachesize being too large
67dac4e Add unit tests for the CuckooCache (Jeremy Rubin)
c9e69fb Add CuckooCache implementation and replace the sigcache map_type with it (Jeremy Rubin)
SQUASHME: Change cuckoocache to only work for powers of two, to avoid mod operator
SQUASHME: Update Documentation and simplify logarithm logic
SQUASHME: OSX Build Errors
SQUASHME: minor Feedback from sipa + bluematt
SQUASHME: DOCONLY: Clarify a few comments.
Remove the nType and nVersion as parameters to all serialization methods
and functions. There is only one place where it's read and has an impact
(in CAddress), and even there it does not impact any of the recursively
invoked serializers.
Instead, the few places that need nType or nVersion are changed to read
it directly from the stream object, through GetType() and GetVersion()
methods which are added to all stream classes.
Given that in default GetSerializeSize implementations created by
ADD_SERIALIZE_METHODS we're already using CSizeComputer(), get rid
of the specialized GetSerializeSize methods everywhere, and just use
CSizeComputer. This removes a lot of code which isn't actually used
anywhere.
For CCompactSize and CVarInt this actually removes a more efficient
size computing algorithm, which is brought back in a later commit.
The stream implementations had two cascading layers (the upper one
with operator<< and operator>>, and a lower one with read and write).
The lower layer's functions are never cascaded (nor should they, as
they should only be used from the higher layer), so make them return
void instead.
Makes it an error to use flags that have not been defined
on the libconsensus API.
There has been some confusion as to what pass to libconsensus, and
(combined with mention in the release notes) this should clear it up.
Using undocumented flags is a risk because their meaning,
and what combinations are allowed, changes from release to release.
E.g. it is no longer possible to pass (CLEANSTACK | P2SH) without
running into an assertion after the segwit changes.
35fe039 Rename to PrecomputedTransactionData (Pieter Wuille)
ab48c5e Unit test for sighash caching (Nicolas DORIER)
d2c5d04 Precompute sighashes (Pieter Wuille)
fafe7b3 contrib: Make fix-copyright-headers.py more portable (MarcoFalke)
fa27c0a [doc] Fix typos in comments, doxygen: Fix comment syntax (MarcoFalke)
fabfd5d [qa] pull-tester: Don't mute zmq ImportError (MarcoFalke)
67a5502 init: Fix typo in help message for -whitelistforcerelay (Wladimir J. van der Laan)
script_tests: always test bitcoinconsensus_verify_script_with_amount if VERIFY_WITNESS isn't set
Rename internal method + make it static
trim bitcoinconsensus_ prefix
Add SERIALIZE_TRANSACTION_WITNESS flag
d1d7775 Improve worst-case behavior of CScript::FindAndDelete (Patrick Strateman)
e2a30bc Unit test for CScript::FindAndDelete (Gavin Andresen)
c0f660c Replace c-style cast with c++ style static_cast. (Patrick Strateman)
ec9ad5f Replace memcmp with std::equal in CScript::FindAndDelete (Patrick Strateman)
- Replace NOP3 with CHECKSEQUENCEVERIFY (BIP112)
<nSequence> CHECKSEQUENCEVERIFY -> <nSequence>
- Fails if txin.nSequence < nSequence, allowing funds of a txout to be locked for a number of blocks or a duration of time after its inclusion in a block.
- Pull most of CheckLockTime() out into VerifyLockTime(), a local function that will be reused for CheckSequence()
- Add bitwise AND operator to CScriptNum
- Enable CHECKSEQUENCEVERIFY as a standard script verify flag
- Transactions that fail CSV verification will be rejected from the mempool, making it easy to test the feature. However blocks containing "invalid" CSV-using transactions will still be accepted; this is *not* the soft-fork required to actually enable CSV for production use.
SequenceLocks functions are used to evaluate sequence lock times or heights per BIP 68.
The majority of this code is copied from maaku in #6312
Further credit: btcdrak, sipa, NicolasDorier
Previously only one PUSHDATA was allowed, needlessly limiting
applications such as matching OP_RETURN contents with bloom filters that
operate on a per-PUSHDATA level. Now any combination that passes
IsPushOnly() is allowed, so long as the total size of the scriptPubKey
is less than 42 bytes. (unchanged modulo non-minimal PUSHDATA encodings)
Also, this fixes the odd bug where previously the PUSHDATA could be
replaced by any single opcode, even sigops consuming opcodes such as
CHECKMULTISIG. (20 sigops!)
Previously unlike other transaction types the TX_SCRIPTHASH would not
clear vSolutionsRet, which means that unlike other transaction types if
it was called twice in a row you would get the result of the previous
invocation as well.
af3208b Resolve issue 3166. These changes decode valid SIGHASH types on signatures in assembly (asm) representations of scriptSig scripts. This squashed commit incorporates substantial helpful feedback from jtimon, laanwj, and sipa. (mruddy)
c5c1edf Fix spelling mistake in -> if. (Mark Friedenbach)
e846b2a Correct a possibly intentional pun that is nevertheless hard to read: "two times of nLockTime." What is meant is that there are two kinds, or categories of nLockTime. (Mark Friedenbach)
These changes decode valid SIGHASH types on signatures in assembly (asm) representations of scriptSig scripts.
This squashed commit incorporates substantial helpful feedback from jtimon, laanwj, and sipa.
ffd75ad Enable CHECKLOCKTIMEVERIFY as a standard script verify flag (Peter Todd)
bc60b2b Replace NOP2 with CHECKLOCKTIMEVERIFY (BIP65) (Peter Todd)
48e9c57 Move LOCKTIME_THRESHOLD to src/script/script.h (Peter Todd)
99088d6 Make CScriptNum() take nMaxNumSize as an argument (Peter Todd)
Transactions that fail CLTV verification will be rejected from the
mempool, making it easy to test the feature. However blocks containing
"invalid" CLTV-using transactions will still be accepted; this is *not*
the soft-fork required to actually enable CLTV for production use.
<nLockTime> CHECKLOCKTIMEVERIFY -> <nLockTime>
Fails if tx.nLockTime < nLockTime, allowing the funds in a txout to be
locked until some block height or block time in the future is reached.
Only the logic and unittests are implemented; this commit does not have
any actual soft-fork logic in it.
Thanks to Pieter Wuille for rebase.
Credit goes to Gregory Maxwell for the suggestion of comparing the
argument against the transaction nLockTime rather than the current
time/blockheight directly.
Makes it possible to compactly provide a delibrately invalid signature
for use with CHECK(MULTI)SIG. For instance with BIP19 if m != n invalid
signatures need to be provided in the scriptSig; prior to this change
those invalid signatures would need to be large DER-encoded signatures.
Note that we may want to further expand on this change in the future by
saying that only OP_0 is a "valid" invalid signature; BIP19 even with
this change is inherently malleable as the invalid signatures can be any
validly encoded DER signature.
If uint256() constructor takes a string, uint256(0) will become
dangerous when uint256 does not take integers anymore (it will go
through std::string(const char*) making a NULL string, and the explicit
keyword is no help).
SignatureHash and its test function SignatureHashOld
return uint256(1) as a special error signaling value.
Return a local static constant with the same value instead.
Previously an empty script wouldn't be hashed, and CScriptID would be
assigned the incorrect value of 0 instead. This bug can be seen in the
RPC decodescript command:
$ btc decodescript ""
{
"asm" : "",
"type" : "nonstandard",
"p2sh" : "31h1vYVSYuKP6AhS86fbRdMw9XHieotbST"
}
Correct output:
$ btc decodescript ""
{
"asm" : "",
"type" : "nonstandard",
"p2sh" : "3J98t1WpEZ73CNmQviecrnyiWrnqRhWNLy"
}
Based on an earlier patch by Peter Todd, though the rules here are different
(P2SH scripts should not have a CLEANSTACK check before the P2SH evaluation).
This turns STRICTENC turn into a softforking-safe change (even though it
is not intended as a consensus rule), and as a result guarantee that using
it for mempool validation only results in consensus-valid transactions in
the mempool.
NOP1 to NOP10 are reserved for future soft-fork upgrades. In the event
of an upgrade such NOPs have *VERIFY behavior, meaning that if their
arguments are not correct the script fails. Discouraging these NOPs by
rejecting transactions containing them from the mempool ensures that
we'll never accept transactions, nor mine blocks, with scripts that are
now invalid according to the majority of hashing power even if we're not
yet upgraded. Previously this wasn't an issue as the IsStandard() rules
didn't allow upgradable NOPs anyway, but 7f3b4e95 relaxed the
IsStandard() rules for P2SH redemptions allowing any redeemScript to be
spent.
We *do* allow upgradable NOPs in scripts so long as they are not
executed. This is harmless as there is no opportunity for the script to
be invalid post-upgrade.
Attempt to codify the possible error statuses associated with script
validation. script/types.h has been created with the expectation that it will
be part of the public lib interface. The other flag enums will be moved here in
a future commit.
Logging has also been removed in order to drop the dependency on core.h. It can
be re-added to bitcoind as-needed. This makes script verification finally free
of application state and boost!
