consensus/clique, miner: remove clique -> accounts dependency (#30642)

Clique currently depends on the `accounts` package. This was a bit of a
big cannon even in the past, just to pass a signer "account" to the
Clique block producer. Either way, nowadays Geth does not support clique
mining any more, so by removing that bit of functionality from our code,
we can also break this dependency.

Clique should ideally be further torn out, but this at least gets us one
step closer to cleanups.

consensus/clique/clique.go

@@ -27,7 +27,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/common/lru"
@@ -50,8 +49,6 @@ const (
 	checkpointInterval = 1024 // Number of blocks after which to save the vote snapshot to the database
 	inmemorySnapshots  = 128  // Number of recent vote snapshots to keep in memory
 	inmemorySignatures = 4096 // Number of recent block signatures to keep in memory
-
-	wiggleTime = 500 * time.Millisecond // Random delay (per signer) to allow concurrent signers
 )
 
 // Clique proof-of-authority protocol constants.
@@ -140,9 +137,6 @@ var (
 	errRecentlySigned = errors.New("recently signed")
 )
 
-// SignerFn hashes and signs the data to be signed by a backing account.
-type SignerFn func(signer accounts.Account, mimeType string, message []byte) ([]byte, error)
-
 // ecrecover extracts the Ethereum account address from a signed header.
 func ecrecover(header *types.Header, sigcache *sigLRU) (common.Address, error) {
 	// If the signature's already cached, return that
@@ -180,7 +174,6 @@ type Clique struct {
 	proposals map[common.Address]bool // Current list of proposals we are pushing
 
 	signer common.Address // Ethereum address of the signing key
-	signFn SignerFn       // Signer function to authorize hashes with
 	lock   sync.RWMutex   // Protects the signer and proposals fields
 
 	// The fields below are for testing only
@@ -602,82 +595,17 @@ func (c *Clique) FinalizeAndAssemble(chain consensus.ChainHeaderReader, header *
 
 // Authorize injects a private key into the consensus engine to mint new blocks
 // with.
-func (c *Clique) Authorize(signer common.Address, signFn SignerFn) {
+func (c *Clique) Authorize(signer common.Address) {
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
 	c.signer = signer
-	c.signFn = signFn
 }
 
 // Seal implements consensus.Engine, attempting to create a sealed block using
 // the local signing credentials.
 func (c *Clique) Seal(chain consensus.ChainHeaderReader, block *types.Block, results chan<- *types.Block, stop <-chan struct{}) error {
-	header := block.Header()
-
-	// Sealing the genesis block is not supported
-	number := header.Number.Uint64()
-	if number == 0 {
-		return errUnknownBlock
-	}
-	// For 0-period chains, refuse to seal empty blocks (no reward but would spin sealing)
-	if c.config.Period == 0 && len(block.Transactions()) == 0 {
-		return errors.New("sealing paused while waiting for transactions")
-	}
-	// Don't hold the signer fields for the entire sealing procedure
-	c.lock.RLock()
-	signer, signFn := c.signer, c.signFn
-	c.lock.RUnlock()
-
-	// Bail out if we're unauthorized to sign a block
-	snap, err := c.snapshot(chain, number-1, header.ParentHash, nil)
-	if err != nil {
-		return err
-	}
-	if _, authorized := snap.Signers[signer]; !authorized {
-		return errUnauthorizedSigner
-	}
-	// If we're amongst the recent signers, wait for the next block
-	for seen, recent := range snap.Recents {
-		if recent == signer {
-			// Signer is among recents, only wait if the current block doesn't shift it out
-			if limit := uint64(len(snap.Signers)/2 + 1); number < limit || seen > number-limit {
-				return errors.New("signed recently, must wait for others")
-			}
-		}
-	}
-	// Sweet, the protocol permits us to sign the block, wait for our time
-	delay := time.Unix(int64(header.Time), 0).Sub(time.Now()) // nolint: gosimple
-	if header.Difficulty.Cmp(diffNoTurn) == 0 {
-		// It's not our turn explicitly to sign, delay it a bit
-		wiggle := time.Duration(len(snap.Signers)/2+1) * wiggleTime
-		delay += time.Duration(rand.Int63n(int64(wiggle)))
-
-		log.Trace("Out-of-turn signing requested", "wiggle", common.PrettyDuration(wiggle))
-	}
-	// Sign all the things!
-	sighash, err := signFn(accounts.Account{Address: signer}, accounts.MimetypeClique, CliqueRLP(header))
-	if err != nil {
-		return err
-	}
-	copy(header.Extra[len(header.Extra)-extraSeal:], sighash)
-	// Wait until sealing is terminated or delay timeout.
-	log.Trace("Waiting for slot to sign and propagate", "delay", common.PrettyDuration(delay))
-	go func() {
-		select {
-		case <-stop:
-			return
-		case <-time.After(delay):
-		}
-
-		select {
-		case results <- block.WithSeal(header):
-		default:
-			log.Warn("Sealing result is not read by miner", "sealhash", SealHash(header))
-		}
-	}()
-
-	return nil
+	panic("clique (poa) sealing not supported any more")
 }
 
 // CalcDifficulty is the difficulty adjustment algorithm. It returns the difficulty

miner/payload_building_test.go

@@ -22,7 +22,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/beacon/engine"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/consensus"
@@ -114,9 +113,7 @@ func newTestWorkerBackend(t *testing.T, chainConfig *params.ChainConfig, engine
 	case *clique.Clique:
 		gspec.ExtraData = make([]byte, 32+common.AddressLength+crypto.SignatureLength)
 		copy(gspec.ExtraData[32:32+common.AddressLength], testBankAddress.Bytes())
-		e.Authorize(testBankAddress, func(account accounts.Account, s string, data []byte) ([]byte, error) {
-			return crypto.Sign(crypto.Keccak256(data), testBankKey)
-		})
+		e.Authorize(testBankAddress)
 	case *ethash.Ethash:
 	default:
 		t.Fatalf("unexpected consensus engine type: %T", engine)