This commit replaces the deep-copy based state revert mechanism with a
linear complexity journal. This commit also hides several internal
StateDB methods to limit the number of ways in which calling code can
use the journal incorrectly.
As usual consultation and bug fixes to the initial implementation were
provided by @karalabe, @obscuren and @Arachnid. Thank you!
that specifies the maximum number of elements in the `structLogs`
output. This option is useful for debugging a transaction that
involves a large number of repetition.
For example,
```
debug.traceTransaction(tx, {disableStorage: true, limit: 2})
```
shows at most the first two steps in the `structLogs`.
In this commit, core/types's types learn how to encode and decode
themselves as JSON. The encoding is very similar to what the RPC API
uses. The RPC API is missing some output fields (e.g. transaction
signature values) which will be added to the API in a later commit. Some
fields that the API generates are ignored by the decoder methods here.
This CL makes several refactors:
- Define a Tracer interface, implementing the `CaptureState` method
- Add the VM environment as the first argument of
`Tracer.CaptureState`
- Rename existing functionality `StructLogger` an make it an
implementation of `Tracer`
- Delete `StructLogCollector` and make `StructLogger` collect the logs
directly
- Change all callers to use the new `StructLogger` where necessary and
extract logs from that.
- Deletes the apparently obsolete and likely nonfunctional 'TraceCall'
from the eth API.
Callers that only wish accumulated logs can use the `StructLogger`
implementation straightforwardly. Callers that wish to efficiently
capture VM traces and operate on them without excessive copying can now
implement the `Tracer` interface to receive VM state at each step and
do with it as they wish.
This CL also removes the accumulation of logs from the vm.Environment;
this was necessary as part of the refactor, but also simplifies it by
removing a responsibility that doesn't directly belong to the
Environment.
This implements a generic approach to enabling soft forks by allowing
anyone to put in hashes of contracts that should not be interacted from.
This will help "The DAO" in their endevour to stop any whithdrawals from
any DAO contract by convincing the mining community to accept their code
hash.
Consensus rules dictate that objects can only be removed during the
finalisation of the transaction (i.e. after all calls have finished).
Thus calling a suicided contract twice from the same transaction:
A->B(S)->ret(A)->B(S) results in 2 suicides. Calling the suicided
object twice from two transactions: A->B(S), A->B, results in only one
suicide and a call to an empty object.
Our current debug tracing functionality replays all transaction that
were executed prior to the targetted transaction in order to provide
the user with an accurate trace.
As a side effect to calling StateDB.IntermediateRoot it also deletes any
suicides objects. Our tracing code never calls this function because it
isn't interested in the intermediate root. Becasue of this it caused a
bug in the tracing code where transactions that were send to priviously
deleted objects resulted in two suicides rather than one suicide and a
call to an empty object.
Fixes#2542
We used to have reporting of bad blocks, but it was disabled
before the Frontier release. We need it back because users
are usually unable to provide the full RLP data of a bad
block when it occurs.
A shortcoming of this particular implementation is that the
origin peer is not tracked for blocks received during eth/63
sync. No origin peer info is still better than no report at
all though.
This fixes an issue where it's theoretical possible to cause a consensus
failure when hitting the lower end of the difficulty, though pratically
impossible it's worth a fix.
Shutting down geth prints hundreds of annoying error messages in some
cases. The errors appear because the Stop method of eth.ProtocolManager,
miner.Miner and core.TxPool is asynchronous. Left over peer sessions
generate events which are processed after Stop even though the database
has already been closed.
The fix is to make Stop synchronous using sync.WaitGroup.
For eth.ProtocolManager, in order to make use of WaitGroup safe, we need
a way to stop new peer sessions from being added while waiting on the
WaitGroup. The eth protocol Run function now selects on a signaling
channel and adds to the WaitGroup only if ProtocolManager is not
shutting down.
For miner.worker and core.TxPool the number of goroutines is static,
WaitGroup can be used in the usual way without additional
synchronisation.
This is necessary for external users of the go-ethereum code who want to, for instance, build a custom node that plays back transactions, as core.ApplyTransaction requires a ChainConfig as a parameter.
According to our own instructions the genesis config attribute should be
"config". The genesis definition in the go code, however, has a field
called `ChainConfig`. This field now has a `json:"config"` struct tag so
that the json is properly unmarshalled.
This fixes#2482
Exposes some core methods to transition and compute new state
information and adds an additional return value to the transition db
method to fetch required gas for that particular message (excluding gas
refunds from any SSTORE[X] = 0 and SUICIDE.
Fixes#2395
The chain maker and the simulated backend now run with a homestead phase
beginning at block 0 (i.e. there's no frontier).
This commit also fixes up #2388
Added chain configuration options and write out during genesis database
insertion. If no "config" was found, nothing is written to the database.
Configurations are written on a per genesis base. This means
that any chain (which is identified by it's genesis hash) can have their
own chain settings.
The EVM was previously initialised and created for every CALL, CALLCODE,
DELEGATECALL and CREATE. This PR changes this behaviour so that the same
EVM can be used through the session and beyond as long as the
Environment sticks around.
Added a future lock which prevents the anything being added or removed
from or to the set when looping over the set of blocks. This fixes a nil
pointer in the range loop when trying to retrieve a block from the set
which was previously available but removed due to regular chain
processing.
Fixes#2305
Previously all blocks that were already in our chain were never re
announced as potential uncle block (e.g. ChainSideEvent). This is
problematic during mining where you want to gather as much possible
uncles as possible increasing the profit. This is now addressed in this
PR where during reorganisations of chains the old chain is regarded as
uncles.
Fixed#2298
Assuming the following scenario where a miner has 15% of all hashing
power and the ability to exert a moderate control over the network to
the point where if the attacker sees a message A, it can't stop A from
propagating, but what it **can** do is send a message B and ensure that
most nodes see B before A. The attacker can then selfish mine and
augment selfish mining strategy by giving his own blocks an advantage.
This change makes the time at which a block is received less relevant
and so the level of control an attacker has over the network no longer
makes a difference.
This change changes the current td algorithm `B_td > C_td` to the new
algorithm `B_td > C_td || B_td == C_td && rnd < 0.5`.
* Removed some strange code that didn't apply state reverting properly
* Refactored code setting from vm & state transition to the executioner
* Updated tests
* change gas cost for contract creating txs
* invalidate signature with s value greater than secp256k1 N / 2
* OOG contract creation if not enough gas to store code
* new difficulty adjustment algorithm
* new DELEGATECALL op code
Pending logs are now filterable through the Go API. Filter API changed
such that each filter type has it's own bucket and adding filter
explicitly requires you specify the bucket to put it in.
Implemented `runtime.Call` which uses - unlike Execute - the given state
for the execution and the address of the contract you wish to execute.
Unlike `Execute`, `Call` requires a config.
The test chain generated by makeChainFork included invalid uncle
headers, crashing the generator during the state commit.
The headers were invalid because they used the iteration counter as the
block number, even though makeChainFork uses a block with number > 0 as
the parent. Fix this by introducing BlockGen.Number, which allows
accessing the actual number of the block being generated.
When a chain reorganisation occurs we collect the logs that were deleted
during the chain reorganisation. The removed logs are posted to the
event mux indicating that those were deleted during the reorg.
The runtime environment can be used for simple basic execution of
contract code without the requirement of setting up a full stack and
operates fully in memory.
This removes the burden on a single object to take care of all
validation and state processing. Now instead the validation is done by
the `core.BlockValidator` (`types.Validator`) that takes care of both
header and uncle validation through the `ValidateBlock` method and state
validation through the `ValidateState` method. The state processing is
done by a new object `core.StateProcessor` (`types.Processor`) and
accepts a new state as input and uses that to process the given block's
transactions (and uncles for rewords) to calculate the state root for
the next block (P_n + 1).
The amount of gas available for tx execution was tracked in the
StateObject representing the coinbase account. This commit makes the gas
counter a separate type in package core, which avoids unintended
consequences of intertwining the counter with state logic.
Moved the execution of instructions to the instruction it self. This
will allow for specialised instructions (e.g. segments) to be execution
in the same manner as regular instructions.
