Seems it was forgotten about when IsPushOnly() and the unittests were
written. A particular oddity is that OP_RESERVED doesn't count towards
the >201 opcode limit unlike every other named opcode.
To fix a minor malleability found by Sergio Lerner (reported here:
https://bitcointalk.org/index.php?topic=8392.msg1245898#msg1245898)
The problem is that if (R,S) is a valid ECDSA signature for a given
message and public key, (R,-S) is also valid. Modulo N (the order
of the secp256k1 curve), this means that both (R,S) and (R,N-S) are
valid. Given that N is odd, S and N-S have a different lowest bit.
We solve the problem by forcing signatures to have an even S value,
excluding one of the alternatives.
This commit just changes the signing code to always produce even S
values, and adds a verification mode to check it. This code is not
enabled anywhere yet. Existing tests in key_tests.cpp verify that
the produced signatures are still valid.
This function finds all keys affected by a particular output script,
supporting everything ExtractDestinations supports (pay-to-pubkey,
pay-to-pubkeyhash, multisig) and recurses into subscripts (P2SH).
Removed AreInputsStandard from CTransaction, made it a regular function in main.
Moved CTransaction::GetOutputFor to CCoinsViewCache.
Moved GetLegacySigOpCount and GetP2SHSigOpCount out of CTransaction into regular functions in main.
Moved GetValueIn and HaveInputs from CTransaction into CCoinsViewCache.
Moved AllowFree, ClientCheckInputs, CheckInputs, UpdateCoins, and CheckTransaction out of CTransaction and into main.
Moved IsStandard and IsFinal out of CTransaction and put them in main as IsStandardTx and IsFinalTx. Moved GetValueOut out of CTransaction into main. Moved CTxIn, CTxOut, and CTransaction into core.
Added minimum fee parameter to CTxOut::IsDust() temporarily until CTransaction is moved to core.h so that CTxOut needn't know about CTransaction.
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.
- ensure warnings always start with "Warning:" and that the first
character after ":" is written uppercase
- ensure the first sentence in warnings ends with an "!"
- remove unneeded spaces from Warning-strings
- add missing Warning-string translation
- remove a "\n" and replace with untranslatable "<br><br>"
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.
- Easier for debugging (what opcode was 0x... again?)
- Clarifies that the opcodes are set in stone in the protocol, and signals that it is impossible to insert opcodes in between.
In ISO C++, the signedness of 'char' is undefined. On some platforms (e.g.
ARM), 'char' is an unsigned type, but some of the code relies on 'char' being
signed (as it is on x86). This is indicated by compiler warnings like this:
bignum.h: In constructor 'CBigNum::CBigNum(char)':
bignum.h:81:59: warning: comparison is always true due to limited range of data type [-Wtype-limits]
util.cpp: In function 'bool IsHex(const string&)':
util.cpp:427:28: warning: comparison is always false due to limited range of data type [-Wtype-limits]
In particular, IsHex erroneously returned true regardless of the input
characters, as long as the length of the string was a positive multiple of 2.
Note: For testing, it's possible using GCC to force char to be unsigned by
adding the -funsigned-char parameter to xCXXFLAGS.
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.
Instead of conversion functions between pubkey/uint160/address in
base58.h, have a fully fledged class CBitcoinAddress (CAddress was
already taken) to represent addresses.
In the assert()s take advantage of the fact that string constants
("string") are effectively of type 'const char []', which when used in
an expression yield a non-NULL pointer.
An assertion that should always fail can thus be formulated as:
assert(!"fail);
An assertion where a text message should be added to the expression can
be written as such:
assert("message" && expression);
Signed-off-by: Giel van Schijndel <me@mortis.eu>
* A new class CKeyStore manages private keys, and script.cpp depends on access to CKeyStore.
* A new class CWallet extends CKeyStore, and contains all former wallet-specific globals; CWallet depends on script.cpp, not the other way around.
* Wallet-specific functions in CTransaction/CTxIn/CTxOut (GetDebit, GetCredit, GetChange, IsMine, IsFromMe), are moved to CWallet, taking their former 'this' argument as an explicit parameter
* CWalletTx objects know which CWallet they belong to, for convenience, so they have their own direct (and caching) GetDebit/... functions.
* Some code was moved from CWalletDB to CWallet, such as handling of reserve keys.
* Main.cpp keeps a set of all 'registered' wallets, which should be informed about updates to the block chain, and does not have any notion about any 'main' wallet. Function in main.cpp that require a wallet (such as GenerateCoins), take an explicit CWallet* argument.
* The actual CWallet instance used by the application is defined in init.cpp as "CWallet* pwalletMain". rpc.cpp and ui.cpp use this variable.
* Functions in main.cpp and db.cpp that are not used by other modules are marked static.
* The code for handling the 'submitorder' message is removed, as it not really compatible with the idea that a node is independent from the wallet(s) connected to it, and obsolete anyway.
This introduces two new source files, keystore.cpp and wallet.cpp with
corresponding headers. Code is moved from main and db, in a preparation
for a follow-up commit which introduces the classes CWallet and CKeyStore.
Gavin Andresen