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-rw-r--r--vendor/github.com/ethereum/ethash/ethash.go440
1 files changed, 0 insertions, 440 deletions
diff --git a/vendor/github.com/ethereum/ethash/ethash.go b/vendor/github.com/ethereum/ethash/ethash.go
deleted file mode 100644
index 8e5cd8128..000000000
--- a/vendor/github.com/ethereum/ethash/ethash.go
+++ /dev/null
@@ -1,440 +0,0 @@
-// Copyright 2015 The go-ethereum Authors
-// Copyright 2015 Lefteris Karapetsas <lefteris@refu.co>
-// Copyright 2015 Matthew Wampler-Doty <matthew.wampler.doty@gmail.com>
-// 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
-
-/*
-#include "src/libethash/internal.h"
-
-int ethashGoCallback_cgo(unsigned);
-*/
-import "C"
-
-import (
- "errors"
- "fmt"
- "io/ioutil"
- "math/big"
- "math/rand"
- "os"
- "os/user"
- "path/filepath"
- "runtime"
- "sync"
- "sync/atomic"
- "time"
- "unsafe"
-
- "github.com/ethereum/go-ethereum/common"
- "github.com/ethereum/go-ethereum/crypto"
- "github.com/ethereum/go-ethereum/log"
- "github.com/ethereum/go-ethereum/pow"
-)
-
-var (
- maxUint256 = new(big.Int).Exp(big.NewInt(2), big.NewInt(256), big.NewInt(0))
- sharedLight = new(Light)
-)
-
-const (
- epochLength uint64 = 30000
- cacheSizeForTesting C.uint64_t = 1024
- dagSizeForTesting C.uint64_t = 1024 * 32
-)
-
-var DefaultDir = defaultDir()
-
-func defaultDir() string {
- home := os.Getenv("HOME")
- if user, err := user.Current(); err == nil {
- home = user.HomeDir
- }
- if runtime.GOOS == "windows" {
- return filepath.Join(home, "AppData", "Ethash")
- }
- return filepath.Join(home, ".ethash")
-}
-
-// cache wraps an ethash_light_t with some metadata
-// and automatic memory management.
-type cache struct {
- epoch uint64
- used time.Time
- test bool
-
- gen sync.Once // ensures cache is only generated once.
- ptr *C.struct_ethash_light
-}
-
-// generate creates the actual cache. it can be called from multiple
-// goroutines. the first call will generate the cache, subsequent
-// calls wait until it is generated.
-func (cache *cache) generate() {
- cache.gen.Do(func() {
- started := time.Now()
- seedHash := makeSeedHash(cache.epoch)
- log.Debug(fmt.Sprintf("Generating cache for epoch %d (%x)", cache.epoch, seedHash))
- size := C.ethash_get_cachesize(C.uint64_t(cache.epoch * epochLength))
- if cache.test {
- size = cacheSizeForTesting
- }
- cache.ptr = C.ethash_light_new_internal(size, (*C.ethash_h256_t)(unsafe.Pointer(&seedHash[0])))
- runtime.SetFinalizer(cache, freeCache)
- log.Debug(fmt.Sprintf("Done generating cache for epoch %d, it took %v", cache.epoch, time.Since(started)))
- })
-}
-
-func freeCache(cache *cache) {
- C.ethash_light_delete(cache.ptr)
- cache.ptr = nil
-}
-
-func (cache *cache) compute(dagSize uint64, hash common.Hash, nonce uint64) (ok bool, mixDigest, result common.Hash) {
- ret := C.ethash_light_compute_internal(cache.ptr, C.uint64_t(dagSize), hashToH256(hash), C.uint64_t(nonce))
- // Make sure cache is live until after the C call.
- // This is important because a GC might happen and execute
- // the finalizer before the call completes.
- _ = cache
- return bool(ret.success), h256ToHash(ret.mix_hash), h256ToHash(ret.result)
-}
-
-// Light implements the Verify half of the proof of work. It uses a few small
-// in-memory caches to verify the nonces found by Full.
-type Light struct {
- test bool // If set, use a smaller cache size
-
- mu sync.Mutex // Protects the per-epoch map of verification caches
- caches map[uint64]*cache // Currently maintained verification caches
- future *cache // Pre-generated cache for the estimated future DAG
-
- NumCaches int // Maximum number of caches to keep before eviction (only init, don't modify)
-}
-
-// Verify checks whether the block's nonce is valid.
-func (l *Light) Verify(block pow.Block) bool {
- // TODO: do ethash_quick_verify before getCache in order
- // to prevent DOS attacks.
- blockNum := block.NumberU64()
- if blockNum >= epochLength*2048 {
- log.Debug(fmt.Sprintf("block number %d too high, limit is %d", epochLength*2048))
- return false
- }
-
- difficulty := block.Difficulty()
- /* Cannot happen if block header diff is validated prior to PoW, but can
- happen if PoW is checked first due to parallel PoW checking.
- We could check the minimum valid difficulty but for SoC we avoid (duplicating)
- Ethereum protocol consensus rules here which are not in scope of Ethash
- */
- if difficulty.Cmp(common.Big0) == 0 {
- log.Debug(fmt.Sprintf("invalid block difficulty"))
- return false
- }
-
- cache := l.getCache(blockNum)
- dagSize := C.ethash_get_datasize(C.uint64_t(blockNum))
- if l.test {
- dagSize = dagSizeForTesting
- }
- // Recompute the hash using the cache.
- ok, mixDigest, result := cache.compute(uint64(dagSize), block.HashNoNonce(), block.Nonce())
- if !ok {
- return false
- }
-
- // avoid mixdigest malleability as it's not included in a block's "hashNononce"
- if block.MixDigest() != mixDigest {
- return false
- }
-
- // The actual check.
- target := new(big.Int).Div(maxUint256, difficulty)
- return result.Big().Cmp(target) <= 0
-}
-
-func h256ToHash(in C.ethash_h256_t) common.Hash {
- return *(*common.Hash)(unsafe.Pointer(&in.b))
-}
-
-func hashToH256(in common.Hash) C.ethash_h256_t {
- return C.ethash_h256_t{b: *(*[32]C.uint8_t)(unsafe.Pointer(&in[0]))}
-}
-
-func (l *Light) getCache(blockNum uint64) *cache {
- var c *cache
- epoch := blockNum / epochLength
-
- // If we have a PoW for that epoch, use that
- l.mu.Lock()
- if l.caches == nil {
- l.caches = make(map[uint64]*cache)
- }
- if l.NumCaches == 0 {
- l.NumCaches = 3
- }
- c = l.caches[epoch]
- if c == nil {
- // No cached DAG, evict the oldest if the cache limit was reached
- if len(l.caches) >= l.NumCaches {
- var evict *cache
- for _, cache := range l.caches {
- if evict == nil || evict.used.After(cache.used) {
- evict = cache
- }
- }
- log.Debug(fmt.Sprintf("Evicting DAG for epoch %d in favour of epoch %d", evict.epoch, epoch))
- delete(l.caches, evict.epoch)
- }
- // If we have the new DAG pre-generated, use that, otherwise create a new one
- if l.future != nil && l.future.epoch == epoch {
- log.Debug(fmt.Sprintf("Using pre-generated DAG for epoch %d", epoch))
- c, l.future = l.future, nil
- } else {
- log.Debug(fmt.Sprintf("No pre-generated DAG available, creating new for epoch %d", epoch))
- c = &cache{epoch: epoch, test: l.test}
- }
- l.caches[epoch] = c
-
- // If we just used up the future cache, or need a refresh, regenerate
- if l.future == nil || l.future.epoch <= epoch {
- log.Debug(fmt.Sprintf("Pre-generating DAG for epoch %d", epoch+1))
- l.future = &cache{epoch: epoch + 1, test: l.test}
- go l.future.generate()
- }
- }
- c.used = time.Now()
- l.mu.Unlock()
-
- // Wait for generation finish and return the cache
- c.generate()
- return c
-}
-
-// dag wraps an ethash_full_t with some metadata
-// and automatic memory management.
-type dag struct {
- epoch uint64
- test bool
- dir string
-
- gen sync.Once // ensures DAG is only generated once.
- ptr *C.struct_ethash_full
-}
-
-// generate creates the actual DAG. it can be called from multiple
-// goroutines. the first call will generate the DAG, subsequent
-// calls wait until it is generated.
-func (d *dag) generate() {
- d.gen.Do(func() {
- var (
- started = time.Now()
- seedHash = makeSeedHash(d.epoch)
- blockNum = C.uint64_t(d.epoch * epochLength)
- cacheSize = C.ethash_get_cachesize(blockNum)
- dagSize = C.ethash_get_datasize(blockNum)
- )
- if d.test {
- cacheSize = cacheSizeForTesting
- dagSize = dagSizeForTesting
- }
- if d.dir == "" {
- d.dir = DefaultDir
- }
- log.Info(fmt.Sprintf("Generating DAG for epoch %d (size %d) (%x)", d.epoch, dagSize, seedHash))
- // Generate a temporary cache.
- // TODO: this could share the cache with Light
- cache := C.ethash_light_new_internal(cacheSize, (*C.ethash_h256_t)(unsafe.Pointer(&seedHash[0])))
- defer C.ethash_light_delete(cache)
- // Generate the actual DAG.
- d.ptr = C.ethash_full_new_internal(
- C.CString(d.dir),
- hashToH256(seedHash),
- dagSize,
- cache,
- (C.ethash_callback_t)(unsafe.Pointer(C.ethashGoCallback_cgo)),
- )
- if d.ptr == nil {
- panic("ethash_full_new IO or memory error")
- }
- runtime.SetFinalizer(d, freeDAG)
- log.Info(fmt.Sprintf("Done generating DAG for epoch %d, it took %v", d.epoch, time.Since(started)))
- })
-}
-
-func freeDAG(d *dag) {
- C.ethash_full_delete(d.ptr)
- d.ptr = nil
-}
-
-func (d *dag) Ptr() unsafe.Pointer {
- return unsafe.Pointer(d.ptr.data)
-}
-
-//export ethashGoCallback
-func ethashGoCallback(percent C.unsigned) C.int {
- log.Info(fmt.Sprintf("Generating DAG: %d%%", percent))
- return 0
-}
-
-// MakeDAG pre-generates a DAG file for the given block number in the
-// given directory. If dir is the empty string, the default directory
-// is used.
-func MakeDAG(blockNum uint64, dir string) error {
- d := &dag{epoch: blockNum / epochLength, dir: dir}
- if blockNum >= epochLength*2048 {
- return fmt.Errorf("block number too high, limit is %d", epochLength*2048)
- }
- d.generate()
- if d.ptr == nil {
- return errors.New("failed")
- }
- return nil
-}
-
-// Full implements the Search half of the proof of work.
-type Full struct {
- Dir string // use this to specify a non-default DAG directory
-
- test bool // if set use a smaller DAG size
- turbo bool
- hashRate int32
-
- mu sync.Mutex // protects dag
- current *dag // current full DAG
-}
-
-func (pow *Full) getDAG(blockNum uint64) (d *dag) {
- epoch := blockNum / epochLength
- pow.mu.Lock()
- if pow.current != nil && pow.current.epoch == epoch {
- d = pow.current
- } else {
- d = &dag{epoch: epoch, test: pow.test, dir: pow.Dir}
- pow.current = d
- }
- pow.mu.Unlock()
- // wait for it to finish generating.
- d.generate()
- return d
-}
-
-func (pow *Full) Search(block pow.Block, stop <-chan struct{}, index int) (nonce uint64, mixDigest []byte) {
- dag := pow.getDAG(block.NumberU64())
-
- r := rand.New(rand.NewSource(time.Now().UnixNano()))
- diff := block.Difficulty()
-
- i := int64(0)
- starti := i
- start := time.Now().UnixNano()
- previousHashrate := int32(0)
-
- nonce = uint64(r.Int63())
- hash := hashToH256(block.HashNoNonce())
- target := new(big.Int).Div(maxUint256, diff)
- for {
- select {
- case <-stop:
- atomic.AddInt32(&pow.hashRate, -previousHashrate)
- return 0, nil
- default:
- i++
-
- // we don't have to update hash rate on every nonce, so update after
- // first nonce check and then after 2^X nonces
- if i == 2 || ((i % (1 << 16)) == 0) {
- elapsed := time.Now().UnixNano() - start
- hashes := (float64(1e9) / float64(elapsed)) * float64(i-starti)
- hashrateDiff := int32(hashes) - previousHashrate
- previousHashrate = int32(hashes)
- atomic.AddInt32(&pow.hashRate, hashrateDiff)
- }
-
- ret := C.ethash_full_compute(dag.ptr, hash, C.uint64_t(nonce))
- result := h256ToHash(ret.result).Big()
-
- // TODO: disagrees with the spec https://github.com/ethereum/wiki/wiki/Ethash#mining
- if ret.success && result.Cmp(target) <= 0 {
- mixDigest = C.GoBytes(unsafe.Pointer(&ret.mix_hash), C.int(32))
- atomic.AddInt32(&pow.hashRate, -previousHashrate)
- return nonce, mixDigest
- }
- nonce += 1
- }
-
- if !pow.turbo {
- time.Sleep(20 * time.Microsecond)
- }
- }
-}
-
-func (pow *Full) GetHashrate() int64 {
- return int64(atomic.LoadInt32(&pow.hashRate))
-}
-
-func (pow *Full) Turbo(on bool) {
- // TODO: this needs to use an atomic operation.
- pow.turbo = on
-}
-
-// Ethash combines block verification with Light and
-// nonce searching with Full into a single proof of work.
-type Ethash struct {
- *Light
- *Full
-}
-
-// New creates an instance of the proof of work.
-func New() *Ethash {
- return &Ethash{new(Light), &Full{turbo: true}}
-}
-
-// NewShared creates an instance of the proof of work., where a single instance
-// of the Light cache is shared across all instances created with NewShared.
-func NewShared() *Ethash {
- return &Ethash{sharedLight, &Full{turbo: true}}
-}
-
-// NewForTesting creates a proof of work for use in unit tests.
-// It uses a smaller DAG and cache size to keep test times low.
-// DAG files are stored in a temporary directory.
-//
-// Nonces found by a testing instance are not verifiable with a
-// regular-size cache.
-func NewForTesting() (*Ethash, error) {
- dir, err := ioutil.TempDir("", "ethash-test")
- if err != nil {
- return nil, err
- }
- return &Ethash{&Light{test: true}, &Full{Dir: dir, test: true}}, nil
-}
-
-func GetSeedHash(blockNum uint64) ([]byte, error) {
- if blockNum >= epochLength*2048 {
- return nil, fmt.Errorf("block number too high, limit is %d", epochLength*2048)
- }
- sh := makeSeedHash(blockNum / epochLength)
- return sh[:], nil
-}
-
-func makeSeedHash(epoch uint64) (sh common.Hash) {
- for ; epoch > 0; epoch-- {
- sh = crypto.Sha3Hash(sh[:])
- }
- return sh
-}