// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package clique
import (
"bytes"
"crypto/ecdsa"
"sort"
"testing"
"github.com/dexon-foundation/dexon/common"
"github.com/dexon-foundation/dexon/core"
"github.com/dexon-foundation/dexon/core/types"
"github.com/dexon-foundation/dexon/core/vm"
"github.com/dexon-foundation/dexon/crypto"
"github.com/dexon-foundation/dexon/ethdb"
"github.com/dexon-foundation/dexon/params"
)
// testerAccountPool is a pool to maintain currently active tester accounts,
// mapped from textual names used in the tests below to actual Ethereum private
// keys capable of signing transactions.
type testerAccountPool struct {
accounts map[string]*ecdsa.PrivateKey
}
func newTesterAccountPool() *testerAccountPool {
return &testerAccountPool{
accounts: make(map[string]*ecdsa.PrivateKey),
}
}
// checkpoint creates a Clique checkpoint signer section from the provided list
// of authorized signers and embeds it into the provided header.
func (ap *testerAccountPool) checkpoint(header *types.Header, signers []string) {
auths := make([]common.Address, len(signers))
for i, signer := range signers {
auths[i] = ap.address(signer)
}
sort.Sort(signersAscending(auths))
for i, auth := range auths {
copy(header.Extra[extraVanity+i*common.AddressLength:], auth.Bytes())
}
}
// address retrieves the Ethereum address of a tester account by label, creating
// a new account if no previous one exists yet.
func (ap *testerAccountPool) address(account string) common.Address {
// Return the zero account for non-addresses
if account == "" {
return common.Address{}
}
// Ensure we have a persistent key for the account
if ap.accounts[account] == nil {
ap.accounts[account], _ = crypto.GenerateKey()
}
// Resolve and return the Ethereum address
return crypto.PubkeyToAddress(ap.accounts[account].PublicKey)
}
// sign calculates a Clique digital signature for the given block and embeds it
// back into the header.
func (ap *testerAccountPool) sign(header *types.Header, signer string) {
// Ensure we have a persistent key for the signer
if ap.accounts[signer] == nil {
ap.accounts[signer], _ = crypto.GenerateKey()
}
// Sign the header and embed the signature in extra data
sig, _ := crypto.Sign(sigHash(header).Bytes(), ap.accounts[signer])
copy(header.Extra[len(header.Extra)-extraSeal:], sig)
}
// testerVote represents a single block signed by a parcitular account, where
// the account may or may not have cast a Clique vote.
type testerVote struct {
signer string
voted string
auth bool
checkpoint []string
newbatch bool
}
// Tests that Clique signer voting is evaluated correctly for various simple and
// complex scenarios, as well as that a few special corner cases fail correctly.
func TestClique(t *testing.T) {
// Define the various voting scenarios to test
tests := []struct {
epoch uint64
signers []string
votes []testerVote
results []string
failure error
}{
{
// Single signer, no votes cast
signers: []string{"A"},
votes: []testerVote{{signer: "A"}},
results: []string{"A"},
}, {
// Single signer, voting to add two others (only accept first, second needs 2 votes)
signers: []string{"A"},
votes: []testerVote{
{signer: "A", voted: "B", auth: true},
{signer: "B"},
{signer: "A", voted: "C", auth: true},
},
results: []string{"A", "B"},
}, {
// Two signers, voting to add three others (only accept first two, third needs 3 votes already)
signers: []string{"A", "B"},
votes: []testerVote{
{signer: "A", voted: "C", auth: true},
{signer: "B", voted: "C", auth: true},
{signer: "A", voted: "D", auth: true},
{signer: "B", voted: "D", auth: true},
{signer: "C"},
{signer: "A", voted: "E", auth: true},
{signer: "B", voted: "E", auth: true},
},
results: []string{"A", "B", "C", "D"},
}, {
// Single signer, dropping itself (weird, but one less cornercase by explicitly allowing this)
signers: []string{"A"},
votes: []testerVote{
{signer: "A", voted: "A", auth: false},
},
results: []string{},
}, {
// Two signers, actually needing mutual consent to drop either of them (not fulfilled)
signers: []string{"A", "B"},
votes: []testerVote{
{signer: "A", voted: "B", auth: false},
},
results: []string{"A", "B"},
}, {
// Two signers, actually needing mutual consent to drop either of them (fulfilled)
signers: []string{"A", "B"},
votes: []testerVote{
{signer: "A", voted: "B", auth: false},
{signer: "B", voted: "B", auth: false},
},
results: []string{"A"},
}, {
// Three signers, two of them deciding to drop the third
signers: []string{"A", "B", "C"},
votes: []testerVote{
{signer: "A", voted: "C", auth: false},
{signer: "B", voted: "C", auth: false},
},
results: []string{"A", "B"},
}, {
// Four signers, consensus of two not being enough to drop anyone
signers: []string{"A", "B", "C", "D"},
votes: []testerVote{
{signer: "A", voted: "C", auth: false},
{signer: "B", voted: "C", auth: false},
},
results: []string{"A", "B", "C", "D"},
}, {
// Four signers, consensus of three already being enough to drop someone
signers: []string{"A", "B", "C", "D"},
votes: []testerVote{
{signer: "A", voted: "D", auth: false},
{signer: "B", voted: "D", auth: false},
{signer: "C", voted: "D", auth: false},
},
results: []string{"A", "B", "C"},
}, {
// Authorizations are counted once per signer per target
signers: []string{"A", "B"},
votes: []testerVote{
{signer: "A", voted: "C", auth: true},
{signer: "B"},
{signer: "A", voted: "C", auth: true},
{signer: "B"},
{signer: "A", voted: "C", auth: true},
},
results: []string{"A", "B"},
}, {
// Authorizing multiple accounts concurrently is permitted
signers: []string{"A", "B"},
votes: []testerVote{
{signer: "A", voted: "C", auth: true},
{signer: "B"},
{signer: "A", voted: "D", auth: true},
{signer: "B"},
{signer: "A"},
{signer: "B", voted: "D", auth: true},
{signer: "A"},
{signer: "B", voted: "C", auth: true},
},
results: []string{"A", "B", "C", "D"},
}, {
// Deauthorizations are counted once per signer per target
signers: []string{"A", "B"},
votes: []testerVote{
{signer: "A", voted: "B", auth: false},
{signer: "B"},
{signer: "A", voted: "B", auth: false},
{signer: "B"},
{signer: "A", voted: "B", auth: false},
},
results: []string{"A", "B"},
}, {
// Deauthorizing multiple accounts concurrently is permitted
signers: []string{"A", "B", "C", "D"},
votes: []testerVote{
{signer: "A", voted: "C", auth: false},
{signer: "B"},
{signer: "C"},
{signer: "A", voted: "D", auth: false},
{signer: "B"},
{signer: "C"},
{signer: "A"},
{signer: "B", voted: "D", auth: false},
{signer: "C", voted: "D", auth: false},
{signer: "A"},
{signer: "B", voted: "C", auth: false},
},
results: []string{"A", "B"},
}, {
// Votes from deauthorized signers are discarded immediately (deauth votes)
signers: []string{"A", "B", "C"},
votes: []testerVote{
{signer: "C", voted: "B", auth: false},
{signer: "A", voted: "C", auth: false},
{signer: "B", voted: "C", auth: false},
{signer: "A", voted: "B", auth: false},
},
results: []string{"A", "B"},
}, {
// Votes from deauthorized signers are discarded immediately (auth votes)
signers: []string{"A", "B", "C"},
votes: []testerVote{
{signer: "C", voted: "B", auth: false},
{signer: "A", voted: "C", auth: false},
{signer: "B", voted: "C", auth: false},
{signer: "A", voted: "B", auth: false},
},
results: []string{"A", "B"},
}, {
// Cascading changes are not allowed, only the account being voted on may change
signers: []string{"A", "B", "C", "D"},
votes: []testerVote{
{signer: "A", voted: "C", auth: false},
{signer: "B"},
{signer: "C"},
{signer: "A", voted: "D", auth: false},
{signer: "B", voted: "C", auth: false},
{signer: "C"},
{signer: "A"},
{signer: "B", voted: "D", auth: false},
{signer: "C", voted: "D", auth: false},
},
results: []string{"A", "B", "C"},
}, {
// Changes reaching consensus out of bounds (via a deauth) execute on touch
signers: []string{"A", "B", "C", "D"},
votes: []testerVote{
{signer: "A", voted: "C", auth: false},
{signer: "B"},
{signer: "C"},
{signer: "A", voted: "D", auth: false},
{signer: "B", voted: "C", auth: false},
{signer: "C"},
{signer: "A"},
{signer: "B", voted: "D", auth: false},
{signer: "C", voted: "D", auth: false},
{signer: "A"},
{signer: "C", voted: "C", auth: true},
},
results: []string{"A", "B"},
}, {
// Changes reaching consensus out of bounds (via a deauth) may go out of consensus on first touch
signers: []string{"A", "B", "C", "D"},
votes: []testerVote{
{signer: "A", voted: "C", auth: false},
{signer: "B"},
{signer: "C"},
{signer: "A", voted: "D", auth: false},
{signer: "B", voted: "C", auth: false},
{signer: "C"},
{signer: "A"},
{signer: "B", voted: "D", auth: false},
{signer: "C", voted: "D", auth: false},
{signer: "A"},
{signer: "B", voted: "C", auth: true},
},
results: []string{"A", "B", "C"},
}, {
// Ensure that pending votes don't survive authorization status changes. This
// corner case can only appear if a signer is quickly added, removed and then
// readded (or the inverse), while one of the original voters dropped. If a
// past vote is left cached in the system somewhere, this will interfere with
// the final signer outcome.
signers: []string{"A", "B", "C", "D", "E"},
votes: []testerVote{
{signer: "A", voted: "F", auth: true}, // Authorize F, 3 votes needed
{signer: "B", voted: "F", auth: true},
{signer: "C", voted: "F", auth: true},
{signer: "D", voted: "F", auth: false}, // Deauthorize F, 4 votes needed (leave A's previous vote "unchanged")
{signer: "E", voted: "F", auth: false},
{signer: "B", voted: "F", auth: false},
{signer: "C", voted: "F", auth: false},
{signer: "D", voted: "F", auth: true}, // Almost authorize F, 2/3 votes needed
{signer: "E", voted: "F", auth: true},
{signer: "B", voted: "A", auth: false}, // Deauthorize A, 3 votes needed
{signer: "C", voted: "A", auth: false},
{signer: "D", voted: "A", auth: false},
{signer: "B", voted: "F", auth: true}, // Finish authorizing F, 3/3 votes needed
},
results: []string{"B", "C", "D", "E", "F"},
}, {
// Epoch transitions reset all votes to allow chain checkpointing
epoch: 3,
signers: []string{"A", "B"},
votes: []testerVote{
{signer: "A", voted: "C", auth: true},
{signer: "B"},
{signer: "A", checkpoint: []string{"A", "B"}},
{signer: "B", voted: "C", auth: true},
},
results: []string{"A", "B"},
}, {
// An unauthorized signer should not be able to sign blocks
signers: []string{"A"},
votes: []testerVote{
{signer: "B"},
},
failure: errUnauthorizedSigner,
}, {
// An authorized signer that signed recenty should not be able to sign again
signers: []string{"A", "B"},
votes: []testerVote{
{signer: "A"},
{signer: "A"},
},
failure: errRecentlySigned,
}, {
// Recent signatures should not reset on checkpoint blocks imported in a batch
epoch: 3,
signers: []string{"A", "B", "C"},
votes: []testerVote{
{signer: "A"},
{signer: "B"},
{signer: "A", checkpoint: []string{"A", "B", "C"}},
{signer: "A"},
},
failure: errRecentlySigned,
}, {
// Recent signatures should not reset on checkpoint blocks imported in a new
// batch (https://github.com/dexon-foundation/dexon/issues/17593). Whilst this
// seems overly specific and weird, it was a Rinkeby consensus split.
epoch: 3,
signers: []string{"A", "B", "C"},
votes: []testerVote{
{signer: "A"},
{signer: "B"},
{signer: "A", checkpoint: []string{"A", "B", "C"}},
{signer: "A", newbatch: true},
},
failure: errRecentlySigned,
},
}
// Run through the scenarios and test them
for i, tt := range tests {
// Create the account pool and generate the initial set of signers
accounts := newTesterAccountPool()
signers := make([]common.Address, len(tt.signers))
for j, signer := range tt.signers {
signers[j] = accounts.address(signer)
}
for j := 0; j < len(signers); j++ {
for k := j + 1; k < len(signers); k++ {
if bytes.Compare(signers[j][:], signers[k][:]) > 0 {
signers[j], signers[k] = signers[k], signers[j]
}
}
}
// Create the genesis block with the initial set of signers
genesis := &core.Genesis{
ExtraData: make([]byte, extraVanity+common.AddressLength*len(signers)+extraSeal),
}
for j, signer := range signers {
copy(genesis.ExtraData[extraVanity+j*common.AddressLength:], signer[:])
}
// Create a pristine blockchain with the genesis injected
db := ethdb.NewMemDatabase()
genesis.Commit(db)
// Assemble a chain of headers from the cast votes
config := *params.TestChainConfig
config.Clique = ¶ms.CliqueConfig{
Period: 1,
Epoch: tt.epoch,
}
engine := New(config.Clique, db)
engine.fakeDiff = true
blocks, _ := core.GenerateChain(&config, genesis.ToBlock(db), engine, db, len(tt.votes), func(j int, gen *core.BlockGen) {
// Cast the vote contained in this block
gen.SetCoinbase(accounts.address(tt.votes[j].voted))
if tt.votes[j].auth {
var nonce types.BlockNonce
copy(nonce[:], nonceAuthVote)
gen.SetNonce(nonce)
}
})
// Iterate through the blocks and seal them individually
for j, block := range blocks {
// Geth the header and prepare it for signing
header := block.Header()
if j > 0 {
header.ParentHash = blocks[j-1].Hash()
}
header.Extra = make([]byte, extraVanity+extraSeal)
if auths := tt.votes[j].checkpoint; auths != nil {
header.Extra = make([]byte, extraVanity+len(auths)*common.AddressLength+extraSeal)
accounts.checkpoint(header, auths)
}
header.Difficulty = diffInTurn // Ignored, we just need a valid number
// Generate the signature, embed it into the header and the block
accounts.sign(header, tt.votes[j].signer)
blocks[j] = block.WithSeal(header)
}
// Split the blocks up into individual import batches (cornercase testing)
batches := [][]*types.Block{nil}
for j, block := range blocks {
if tt.votes[j].newbatch {
batches = append(batches, nil)
}
batches[len(batches)-1] = append(batches[len(batches)-1], block)
}
// Pass all the headers through clique and ensure tallying succeeds
chain, err := core.NewBlockChain(db, nil, &config, engine, vm.Config{}, nil)
if err != nil {
t.Errorf("test %d: failed to create test chain: %v", i, err)
continue
}
failed := false
for j := 0; j < len(batches)-1; j++ {
if k, err := chain.InsertChain(batches[j]); err != nil {
t.Errorf("test %d: failed to import batch %d, block %d: %v", i, j, k, err)
failed = true
break
}
}
if failed {
continue
}
if _, err = chain.InsertChain(batches[len(batches)-1]); err != tt.failure {
t.Errorf("test %d: failure mismatch: have %v, want %v", i, err, tt.failure)
}
if tt.failure != nil {
continue
}
// No failure was produced or requested, generate the final voting snapshot
head := blocks[len(blocks)-1]
snap, err := engine.snapshot(chain, head.NumberU64(), head.Hash(), nil)
if err != nil {
t.Errorf("test %d: failed to retrieve voting snapshot: %v", i, err)
continue
}
// Verify the final list of signers against the expected ones
signers = make([]common.Address, len(tt.results))
for j, signer := range tt.results {
signers[j] = accounts.address(signer)
}
for j := 0; j < len(signers); j++ {
for k := j + 1; k < len(signers); k++ {
if bytes.Compare(signers[j][:], signers[k][:]) > 0 {
signers[j], signers[k] = signers[k], signers[j]
}
}
}
result := snap.signers()
if len(result) != len(signers) {
t.Errorf("test %d: signers mismatch: have %x, want %x", i, result, signers)
continue
}
for j := 0; j < len(result); j++ {
if !bytes.Equal(result[j][:], signers[j][:]) {
t.Errorf("test %d, signer %d: signer mismatch: have %x, want %x", i, j, result[j], signers[j])
}
}
}
}
