consensus/ethash: expose remote miner api

consensus/ethash/api.go

@@ -0,0 +1,71 @@
+// 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 ethash
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+)
+
+// API exposes ethash related methods for the RPC interface
+type API struct {
+	ethash *Ethash
+}
+
+// GetWork returns a work package for external miner. The work package consists of 3 strings
+// result[0], 32 bytes hex encoded current block header pow-hash
+// result[1], 32 bytes hex encoded seed hash used for DAG
+// result[2], 32 bytes hex encoded boundary condition ("target"), 2^256/difficulty
+func (s *API) GetWork() ([3]string, error) {
+	var (
+		workCh = make(chan [3]string)
+		errCh  = make(chan error)
+	)
+	op := &remoteOp{
+		typ:    getWork,
+		workCh: workCh,
+		errCh:  errCh,
+	}
+	s.ethash.remoteOp <- op
+	err := <-errCh
+	if err == nil {
+		return <-workCh, nil
+	} else {
+		return [3]string{}, err
+	}
+}
+
+// SubmitWork can be used by external miner to submit their POW solution. It returns an indication if the work was
+// accepted. Note, this is not an indication if the provided work was valid!
+func (s *API) SubmitWork(nonce types.BlockNonce, solution, digest common.Hash) bool {
+	var errCh = make(chan error)
+	result := sealResult{
+		nonce:     nonce,
+		mixDigest: digest,
+		hash:      solution,
+	}
+	op := &remoteOp{
+		typ:    submitWork,
+		result: result,
+		errCh:  errCh,
+	}
+	s.ethash.remoteOp <- op
+	if err := <-errCh; err == nil {
+		return true
+	} else {
+		return false
+	}
+}

consensus/ethash/ethash.go

@@ -610,10 +610,14 @@ func (ethash *Ethash) Hashrate() float64 {
 	return ethash.hashrate.Rate1()
 }
 
-// APIs implements consensus.Engine, returning the user facing RPC APIs. Currently
-// that is empty.
+// APIs implements consensus.Engine, returning the user facing RPC APIs.
 func (ethash *Ethash) APIs(chain consensus.ChainReader) []rpc.API {
-	return nil
+	return []rpc.API{{
+		Namespace: "ethash",
+		Version:   "1.0",
+		Service:   &API{ethash},
+		Public:    true,
+	}}
 }
 
 // SeedHash is the seed to use for generating a verification cache and the mining