The 'from' and 'to' methods on StateTransitions are reader methods and
shouldn't have inadvertent side effects on state.
It is safe to remove the check in 'from' because account existence is
implicitly checked by the nonce and balance checks. If the account has
non-zero balance or nonce, it must exist. Even if the sender account has
nonce zero at the start of the state transition or no balance, the nonce
is incremented before execution and the account will be created at that
time.
It is safe to remove the check in 'to' because the EVM creates the
account if necessary.
Fixes#15119
- according to implementation of `IntrinsicGas`
we can continue execution since problem will be detected
later. However, early return is future-proof for changes.
* common: remove CurrencyToString
Move denomination values to params instead.
* common: delete dead code
* common: move big integer operations to common/math
This commit consolidates all big integer operations into common/math and
adds tests and documentation.
There should be no change in semantics for BigPow, BigMin, BigMax, S256,
U256, Exp and their behaviour is now locked in by tests.
The BigD, BytesToBig and Bytes2Big functions don't provide additional
value, all uses are replaced by new(big.Int).SetBytes().
BigToBytes is now called PaddedBigBytes, its minimum output size
parameter is now specified as the number of bytes instead of bits. The
single use of this function is in the EVM's MSTORE instruction.
Big and String2Big are replaced by ParseBig, which is slightly stricter.
It previously accepted leading zeros for hexadecimal inputs but treated
decimal inputs as octal if a leading zero digit was present.
ParseUint64 is used in places where String2Big was used to decode a
uint64.
The new functions MustParseBig and MustParseUint64 are now used in many
places where parsing errors were previously ignored.
* common: delete unused big integer variables
* accounts/abi: replace uses of BytesToBig with use of encoding/binary
* common: remove BytesToBig
* common: remove Bytes2Big
* common: remove BigTrue
* cmd/utils: add BigFlag and use it for error-checked integer flags
While here, remove environment variable processing for DirectoryFlag
because we don't use it.
* core: add missing error checks in genesis block parser
* common: remove String2Big
* cmd/evm: use utils.BigFlag
* common/math: check for 256 bit overflow in ParseBig
This is supposed to prevent silent overflow/truncation of values in the
genesis block JSON. Without this check, a genesis block that set a
balance larger than 256 bits would lead to weird behaviour in the VM.
* cmd/utils: fixup import
Reworked the EVM gas instructions to use 64bit integers rather than
arbitrary size big ints. All gas operations, be it additions,
multiplications or divisions, are checked and guarded against 64 bit
integer overflows.
In additon, most of the protocol paramaters in the params package have
been converted to uint64 and are now constants rather than variables.
* common/math: added overflow check ops
* core: vmenv, env renamed to evm
* eth, internal/ethapi, les: unmetered eth_call and cancel methods
* core/vm: implemented big.Int pool for evm instructions
* core/vm: unexported intPool methods & verification methods
* core/vm: added memoryGasCost overflow check and test
Reworked the EVM gas instructions to use 64bit integers rather than
arbitrary size big ints. All gas operations, be it additions,
multiplications or divisions, are checked and guarded against 64 bit
integer overflows.
In additon, most of the protocol paramaters in the params package have
been converted to uint64 and are now constants rather than variables.
* common/math: added overflow check ops
* core: vmenv, env renamed to evm
* eth, internal/ethapi, les: unmetered eth_call and cancel methods
* core/vm: implemented big.Int pool for evm instructions
* core/vm: unexported intPool methods & verification methods
* core/vm: added memoryGasCost overflow check and test
Removal of dead code that appeard as if we had a consensus issue. This
however is not the case as the proper error catching happens in the vm
package instead.
The run loop, which previously contained custom opcode executes have been
removed and has been simplified to a few checks.
Each operation consists of 4 elements: execution function, gas cost function,
stack validation function and memory size function. The execution function
implements the operation's runtime behaviour, the gas cost function implements
the operation gas costs function and greatly depends on the memory and stack,
the stack validation function validates the stack and makes sure that enough
items can be popped off and pushed on and the memory size function calculates
the memory required for the operation and returns it.
This commit also allows the EVM to go unmetered. This is helpful for offline
operations such as contract calls.
Environment is now a struct (not an interface). This
reduces a lot of tech-debt throughout the codebase where a virtual
machine environment had to be implemented in order to test or run it.
The new environment is suitable to be used en the json tests, core
consensus and light client.
Whenever a private transaction was initiated and executed the address
would be created on the public state when initialising the initial Call.
To prevent this we use the msg's address rather than using the to method
on the state transition object.
Improved private transaction tests by checking existance of private and
public addresses on the incorrect state.
Fixed an issue where public state and private state were mixed during
the initial phase of the state transition. This causes severe issues
when creating new contracts (and addresses) and messes up the public
nonce, which, indirectly, has an effect on the contracts that are
created on the public state for both public and private txs.
This commit implements EIP158 part 1, 2, 3 & 4
1. If an account is empty it's no longer written to the trie. An empty
account is defined as (balance=0, nonce=0, storage=0, code=0).
2. Delete an empty account if it's touched
3. An empty account is redefined as either non-existent or empty.
4. Zero value calls and zero value suicides no longer consume the 25k
reation costs.
params: moved core/config to params
Signed-off-by: Jeffrey Wilcke <jeffrey@ethereum.org>
This commit implements a dual state approach. The dual state approach
separates public and private state by making the core vm environment
context aware.
Although not currently implemented it will need to prohibit value
transfers and it must initialise all transactions from accounts on the
public state. This means that sending transactions increments the
account nonce on the public state and contract addresses are derived
from the public state when initialised by a transaction. For obvious
reasons, contract created by private contracts are still derived from
public state.
This is required in order to have consensus over the public state at all
times as non-private participants would still process the transaction on
the public state even though private payload can not be decrypted. This
means that participants of a private group must do the same in order to
have public consensus. However the creation of the contract and
interaction still occurs on the private state.
It implements support for the following calling model:
S: sender, (X): private, X: public, ->: direction, [ ]: read only mode
1. S -> A -> B
2. S -> (A) -> (B)
3. S -> (A) -> [ B -> C ]
It does not support
1. (S) -> A
2. (S) -> (A)
3. S -> (A) -> B
Implemented "read only" mode for the EVM. Read only mode is checked
during any opcode that could potentially modify the state. If such an
opcode is encountered during "read only", it throws an exception.
The EVM is flagged "read only" when a private contract calls in to
public state.