* aura: broadcast empty step message instead of sealing empty block
* aura: add empty_step messages to seal
* aura: include parent_hash in empty step message
* aura: verify received empty step messages
* aura: verify empty step messages in block
* aura: fix dead lock on empty_steps
* aura: fix EmptyStep Encodable
* aura: take number of empty steps into account in chain score
* aura: use empty step signers for finality
* aura: add empty "empty step" messages to seal when reading from spec
* aura: fix EmptyStep rlp encoding
* aura: use Vec<u8> instead of Bytes
* aura: fix block empty step verification
* Update .gitlab-ci.yml
fix lint
* aura: fix accumulation of empty step signatures for finality
* aura: include empty steps in seal signature
* aura: configurable max number of empty steps
* engine: pass block header to seal_fields method
This is necessary to make the number of seal fields dynamic,
e.g. activating a transition on a certain block number that changes
the seal.
* aura: add transition to enable empty step messages
* aura: clear old empty step messages on verify_block_external
* aura: ignore empty step messages from the future
* aura: report skipped primaries when empty steps are not enabled
* aura: fix tests
* aura: report misbehavior
* aura: add tests for rolling finality with multiple signatures
* engine: fix validator set test
In this test the block validation wasn't failing because the block was in the
future (expected failure) but was instead failing because the author of the
block isn't the expected authority. Since we added reporting of blocks produced
by the wrong authority this test started failing.
* aura: reward all the authors of empty step messages
* aura: fix reward attribution for new blocks
* aura: add tests for empty steps broadcasting and inclusion in blocks
* aura: reduce size of empty step messages in seal
* aura: add test for empty step inclusion in blocks
* aura: add test for rewarding of empty steps
* aura: add test for empty steps validation
* aura: fix rlp encoding of sealed empty step
* aura: fix grumbles
Firstly, `Step.duration_remaining` casts it to u32, unnecesarily
limiting it to 2^32. While theoretically this is "good enough" (at 3
seconds steps it provides room for a little over 400 years), it is
still a lossy way to calculate the remaining time until the next step.
Secondly, step duration might be zero, triggering division by zero
in `Step.calibrate`
Solution: rework the code around the fact that duration is
typically in single digits and never grows, hence, it can be represented
by a much narrower range (u16) and this highlights the fact that
multiplying u64 by u16 will only result in an overflow in even further
future, at which point we should panic informatively (if anybody's
still around)
Similarly, panic when it is detected that incrementing the step
counter wrapped around on the overflow of usize.
As for the division by zero, prevent it by making zero an invalid
value for step duration. This will make AuRa log the constraint
mismatch and panic (after all, what purpose would zero step duration
serve? it makes no sense within the definition of the protocol,
as finality can only be achieved as per the specification
if messages are received within the step duration, which would violate
the speed of light and other physical laws in this case).
* move common forks and parameters to common params
* port specs over to new format
* fix RPC tests
* parity-machine skeleton
* remove block type
* extract out ethereum-specific methods into EthereumMachine
* beginning to integrate Machine into engines. dealing with stale transitions in Ethash
* initial porting to machine
* move block reward back into engine
* abstract block reward logic
* move last hash and DAO HF logic into machine
* begin making engine function parameters generic
* abstract epoch verifier and ethash block reward logic
* instantiate special ethereummachine for ethash in spec
* optional full verification in verify_block_family
* re-instate tx_filter in a way that works for all engines
* fix warnings
* fix most tests, further generalize engine trait
* uncomment nullengine, get ethcore tests compiling
* fix warnings
* update a bunch of specs
* re-enable engine signer, validator set, and transition handler
* migrate basic_authority engine
* move last hashes into executedblock
* port tendermint
* make all ethcore tests pass
* json-tests compilation
* fix RPC tests: change in gas limit for new block changed PoW hash
* fix minor grumbles
* validate chainspecs
* fix broken import
* fix transaction verification for pre-homestead
* final engine changes
* migration to v13
* adding and removing pending transitions
* epoch_transition_for
* port snapshot to new engine methods
* final validator set interface
* fix compiler errors
* revert v13/epoch_depth transition
* make call on new epoch
* rolling finality checker
* tests for finality checker
* constructing finality proof upon pending transition
* fix warnings and finality proof checking
* fix compiler warnings in tests
* test fixes
* don't include genesis in finality checking
* change snapshot test chain building logic
* minor refactorings
* fetch epoch transition based on parent, fix divide-by-zero in SimpleList
* fix formatting
* fix ABIs and finality checking in snapshot restoration
* encode signal number in proof
* create more blocks at the end of tests
* update gist to accurate contract code
* test for epoch_transition_for
* fix tests with immediateTransitions parameter
* disable force flag after forcing
* rename ValidatorsChanged to InitiateChange and finalizeSignal to finalizeChange
* a few more validator set tests
