diff options
Diffstat (limited to 'accounts/keystore')
27 files changed, 2136 insertions, 0 deletions
diff --git a/accounts/keystore/account_cache.go b/accounts/keystore/account_cache.go new file mode 100644 index 0000000..2067ccb --- /dev/null +++ b/accounts/keystore/account_cache.go @@ -0,0 +1,301 @@ +// 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 keystore + +import ( + "bufio" + "encoding/json" + "fmt" + "os" + "path/filepath" + "sort" + "strings" + "sync" + "time" + + "github.com/ava-labs/coreth/accounts" + "github.com/ava-labs/go-ethereum/common" + "github.com/ava-labs/go-ethereum/log" + mapset "github.com/deckarep/golang-set" +) + +// Minimum amount of time between cache reloads. This limit applies if the platform does +// not support change notifications. It also applies if the keystore directory does not +// exist yet, the code will attempt to create a watcher at most this often. +const minReloadInterval = 2 * time.Second + +type accountsByURL []accounts.Account + +func (s accountsByURL) Len() int { return len(s) } +func (s accountsByURL) Less(i, j int) bool { return s[i].URL.Cmp(s[j].URL) < 0 } +func (s accountsByURL) Swap(i, j int) { s[i], s[j] = s[j], s[i] } + +// AmbiguousAddrError is returned when attempting to unlock +// an address for which more than one file exists. +type AmbiguousAddrError struct { + Addr common.Address + Matches []accounts.Account +} + +func (err *AmbiguousAddrError) Error() string { + files := "" + for i, a := range err.Matches { + files += a.URL.Path + if i < len(err.Matches)-1 { + files += ", " + } + } + return fmt.Sprintf("multiple keys match address (%s)", files) +} + +// accountCache is a live index of all accounts in the keystore. +type accountCache struct { + keydir string + watcher *watcher + mu sync.Mutex + all accountsByURL + byAddr map[common.Address][]accounts.Account + throttle *time.Timer + notify chan struct{} + fileC fileCache +} + +func newAccountCache(keydir string) (*accountCache, chan struct{}) { + ac := &accountCache{ + keydir: keydir, + byAddr: make(map[common.Address][]accounts.Account), + notify: make(chan struct{}, 1), + fileC: fileCache{all: mapset.NewThreadUnsafeSet()}, + } + ac.watcher = newWatcher(ac) + return ac, ac.notify +} + +func (ac *accountCache) accounts() []accounts.Account { + ac.maybeReload() + ac.mu.Lock() + defer ac.mu.Unlock() + cpy := make([]accounts.Account, len(ac.all)) + copy(cpy, ac.all) + return cpy +} + +func (ac *accountCache) hasAddress(addr common.Address) bool { + ac.maybeReload() + ac.mu.Lock() + defer ac.mu.Unlock() + return len(ac.byAddr[addr]) > 0 +} + +func (ac *accountCache) add(newAccount accounts.Account) { + ac.mu.Lock() + defer ac.mu.Unlock() + + i := sort.Search(len(ac.all), func(i int) bool { return ac.all[i].URL.Cmp(newAccount.URL) >= 0 }) + if i < len(ac.all) && ac.all[i] == newAccount { + return + } + // newAccount is not in the cache. + ac.all = append(ac.all, accounts.Account{}) + copy(ac.all[i+1:], ac.all[i:]) + ac.all[i] = newAccount + ac.byAddr[newAccount.Address] = append(ac.byAddr[newAccount.Address], newAccount) +} + +// note: removed needs to be unique here (i.e. both File and Address must be set). +func (ac *accountCache) delete(removed accounts.Account) { + ac.mu.Lock() + defer ac.mu.Unlock() + + ac.all = removeAccount(ac.all, removed) + if ba := removeAccount(ac.byAddr[removed.Address], removed); len(ba) == 0 { + delete(ac.byAddr, removed.Address) + } else { + ac.byAddr[removed.Address] = ba + } +} + +// deleteByFile removes an account referenced by the given path. +func (ac *accountCache) deleteByFile(path string) { + ac.mu.Lock() + defer ac.mu.Unlock() + i := sort.Search(len(ac.all), func(i int) bool { return ac.all[i].URL.Path >= path }) + + if i < len(ac.all) && ac.all[i].URL.Path == path { + removed := ac.all[i] + ac.all = append(ac.all[:i], ac.all[i+1:]...) + if ba := removeAccount(ac.byAddr[removed.Address], removed); len(ba) == 0 { + delete(ac.byAddr, removed.Address) + } else { + ac.byAddr[removed.Address] = ba + } + } +} + +func removeAccount(slice []accounts.Account, elem accounts.Account) []accounts.Account { + for i := range slice { + if slice[i] == elem { + return append(slice[:i], slice[i+1:]...) + } + } + return slice +} + +// find returns the cached account for address if there is a unique match. +// The exact matching rules are explained by the documentation of accounts.Account. +// Callers must hold ac.mu. +func (ac *accountCache) find(a accounts.Account) (accounts.Account, error) { + // Limit search to address candidates if possible. + matches := ac.all + if (a.Address != common.Address{}) { + matches = ac.byAddr[a.Address] + } + if a.URL.Path != "" { + // If only the basename is specified, complete the path. + if !strings.ContainsRune(a.URL.Path, filepath.Separator) { + a.URL.Path = filepath.Join(ac.keydir, a.URL.Path) + } + for i := range matches { + if matches[i].URL == a.URL { + return matches[i], nil + } + } + if (a.Address == common.Address{}) { + return accounts.Account{}, ErrNoMatch + } + } + switch len(matches) { + case 1: + return matches[0], nil + case 0: + return accounts.Account{}, ErrNoMatch + default: + err := &AmbiguousAddrError{Addr: a.Address, Matches: make([]accounts.Account, len(matches))} + copy(err.Matches, matches) + sort.Sort(accountsByURL(err.Matches)) + return accounts.Account{}, err + } +} + +func (ac *accountCache) maybeReload() { + ac.mu.Lock() + + if ac.watcher.running { + ac.mu.Unlock() + return // A watcher is running and will keep the cache up-to-date. + } + if ac.throttle == nil { + ac.throttle = time.NewTimer(0) + } else { + select { + case <-ac.throttle.C: + default: + ac.mu.Unlock() + return // The cache was reloaded recently. + } + } + // No watcher running, start it. + ac.watcher.start() + ac.throttle.Reset(minReloadInterval) + ac.mu.Unlock() + ac.scanAccounts() +} + +func (ac *accountCache) close() { + ac.mu.Lock() + ac.watcher.close() + if ac.throttle != nil { + ac.throttle.Stop() + } + if ac.notify != nil { + close(ac.notify) + ac.notify = nil + } + ac.mu.Unlock() +} + +// scanAccounts checks if any changes have occurred on the filesystem, and +// updates the account cache accordingly +func (ac *accountCache) scanAccounts() error { + // Scan the entire folder metadata for file changes + creates, deletes, updates, err := ac.fileC.scan(ac.keydir) + if err != nil { + log.Debug("Failed to reload keystore contents", "err", err) + return err + } + if creates.Cardinality() == 0 && deletes.Cardinality() == 0 && updates.Cardinality() == 0 { + return nil + } + // Create a helper method to scan the contents of the key files + var ( + buf = new(bufio.Reader) + key struct { + Address string `json:"address"` + } + ) + readAccount := func(path string) *accounts.Account { + fd, err := os.Open(path) + if err != nil { + log.Trace("Failed to open keystore file", "path", path, "err", err) + return nil + } + defer fd.Close() + buf.Reset(fd) + // Parse the address. + key.Address = "" + err = json.NewDecoder(buf).Decode(&key) + addr := common.HexToAddress(key.Address) + switch { + case err != nil: + log.Debug("Failed to decode keystore key", "path", path, "err", err) + case (addr == common.Address{}): + log.Debug("Failed to decode keystore key", "path", path, "err", "missing or zero address") + default: + return &accounts.Account{ + Address: addr, + URL: accounts.URL{Scheme: KeyStoreScheme, Path: path}, + } + } + return nil + } + // Process all the file diffs + start := time.Now() + + for _, p := range creates.ToSlice() { + if a := readAccount(p.(string)); a != nil { + ac.add(*a) + } + } + for _, p := range deletes.ToSlice() { + ac.deleteByFile(p.(string)) + } + for _, p := range updates.ToSlice() { + path := p.(string) + ac.deleteByFile(path) + if a := readAccount(path); a != nil { + ac.add(*a) + } + } + end := time.Now() + + select { + case ac.notify <- struct{}{}: + default: + } + log.Trace("Handled keystore changes", "time", end.Sub(start)) + return nil +} diff --git a/accounts/keystore/file_cache.go b/accounts/keystore/file_cache.go new file mode 100644 index 0000000..ac87f0c --- /dev/null +++ b/accounts/keystore/file_cache.go @@ -0,0 +1,102 @@ +// 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 keystore + +import ( + "io/ioutil" + "os" + "path/filepath" + "strings" + "sync" + "time" + + mapset "github.com/deckarep/golang-set" + "github.com/ava-labs/go-ethereum/log" +) + +// fileCache is a cache of files seen during scan of keystore. +type fileCache struct { + all mapset.Set // Set of all files from the keystore folder + lastMod time.Time // Last time instance when a file was modified + mu sync.RWMutex +} + +// scan performs a new scan on the given directory, compares against the already +// cached filenames, and returns file sets: creates, deletes, updates. +func (fc *fileCache) scan(keyDir string) (mapset.Set, mapset.Set, mapset.Set, error) { + t0 := time.Now() + + // List all the failes from the keystore folder + files, err := ioutil.ReadDir(keyDir) + if err != nil { + return nil, nil, nil, err + } + t1 := time.Now() + + fc.mu.Lock() + defer fc.mu.Unlock() + + // Iterate all the files and gather their metadata + all := mapset.NewThreadUnsafeSet() + mods := mapset.NewThreadUnsafeSet() + + var newLastMod time.Time + for _, fi := range files { + path := filepath.Join(keyDir, fi.Name()) + // Skip any non-key files from the folder + if nonKeyFile(fi) { + log.Trace("Ignoring file on account scan", "path", path) + continue + } + // Gather the set of all and fresly modified files + all.Add(path) + + modified := fi.ModTime() + if modified.After(fc.lastMod) { + mods.Add(path) + } + if modified.After(newLastMod) { + newLastMod = modified + } + } + t2 := time.Now() + + // Update the tracked files and return the three sets + deletes := fc.all.Difference(all) // Deletes = previous - current + creates := all.Difference(fc.all) // Creates = current - previous + updates := mods.Difference(creates) // Updates = modified - creates + + fc.all, fc.lastMod = all, newLastMod + t3 := time.Now() + + // Report on the scanning stats and return + log.Debug("FS scan times", "list", t1.Sub(t0), "set", t2.Sub(t1), "diff", t3.Sub(t2)) + return creates, deletes, updates, nil +} + +// nonKeyFile ignores editor backups, hidden files and folders/symlinks. +func nonKeyFile(fi os.FileInfo) bool { + // Skip editor backups and UNIX-style hidden files. + if strings.HasSuffix(fi.Name(), "~") || strings.HasPrefix(fi.Name(), ".") { + return true + } + // Skip misc special files, directories (yes, symlinks too). + if fi.IsDir() || fi.Mode()&os.ModeType != 0 { + return true + } + return false +} diff --git a/accounts/keystore/key.go b/accounts/keystore/key.go new file mode 100644 index 0000000..3654daa --- /dev/null +++ b/accounts/keystore/key.go @@ -0,0 +1,232 @@ +// Copyright 2014 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 keystore + +import ( + "bytes" + "crypto/ecdsa" + "encoding/hex" + "encoding/json" + "fmt" + "io" + "io/ioutil" + "os" + "path/filepath" + "strings" + "time" + + "github.com/ava-labs/coreth/accounts" + "github.com/ava-labs/go-ethereum/common" + "github.com/ava-labs/go-ethereum/crypto" + "github.com/pborman/uuid" +) + +const ( + version = 3 +) + +type Key struct { + Id uuid.UUID // Version 4 "random" for unique id not derived from key data + // to simplify lookups we also store the address + Address common.Address + // we only store privkey as pubkey/address can be derived from it + // privkey in this struct is always in plaintext + PrivateKey *ecdsa.PrivateKey +} + +type keyStore interface { + // Loads and decrypts the key from disk. + GetKey(addr common.Address, filename string, auth string) (*Key, error) + // Writes and encrypts the key. + StoreKey(filename string, k *Key, auth string) error + // Joins filename with the key directory unless it is already absolute. + JoinPath(filename string) string +} + +type plainKeyJSON struct { + Address string `json:"address"` + PrivateKey string `json:"privatekey"` + Id string `json:"id"` + Version int `json:"version"` +} + +type encryptedKeyJSONV3 struct { + Address string `json:"address"` + Crypto CryptoJSON `json:"crypto"` + Id string `json:"id"` + Version int `json:"version"` +} + +type encryptedKeyJSONV1 struct { + Address string `json:"address"` + Crypto CryptoJSON `json:"crypto"` + Id string `json:"id"` + Version string `json:"version"` +} + +type CryptoJSON struct { + Cipher string `json:"cipher"` + CipherText string `json:"ciphertext"` + CipherParams cipherparamsJSON `json:"cipherparams"` + KDF string `json:"kdf"` + KDFParams map[string]interface{} `json:"kdfparams"` + MAC string `json:"mac"` +} + +type cipherparamsJSON struct { + IV string `json:"iv"` +} + +func (k *Key) MarshalJSON() (j []byte, err error) { + jStruct := plainKeyJSON{ + hex.EncodeToString(k.Address[:]), + hex.EncodeToString(crypto.FromECDSA(k.PrivateKey)), + k.Id.String(), + version, + } + j, err = json.Marshal(jStruct) + return j, err +} + +func (k *Key) UnmarshalJSON(j []byte) (err error) { + keyJSON := new(plainKeyJSON) + err = json.Unmarshal(j, &keyJSON) + if err != nil { + return err + } + + u := new(uuid.UUID) + *u = uuid.Parse(keyJSON.Id) + k.Id = *u + addr, err := hex.DecodeString(keyJSON.Address) + if err != nil { + return err + } + privkey, err := crypto.HexToECDSA(keyJSON.PrivateKey) + if err != nil { + return err + } + + k.Address = common.BytesToAddress(addr) + k.PrivateKey = privkey + + return nil +} + +func newKeyFromECDSA(privateKeyECDSA *ecdsa.PrivateKey) *Key { + id := uuid.NewRandom() + key := &Key{ + Id: id, + Address: crypto.PubkeyToAddress(privateKeyECDSA.PublicKey), + PrivateKey: privateKeyECDSA, + } + return key +} + +// NewKeyForDirectICAP generates a key whose address fits into < 155 bits so it can fit +// into the Direct ICAP spec. for simplicity and easier compatibility with other libs, we +// retry until the first byte is 0. +func NewKeyForDirectICAP(rand io.Reader) *Key { + randBytes := make([]byte, 64) + _, err := rand.Read(randBytes) + if err != nil { + panic("key generation: could not read from random source: " + err.Error()) + } + reader := bytes.NewReader(randBytes) + privateKeyECDSA, err := ecdsa.GenerateKey(crypto.S256(), reader) + if err != nil { + panic("key generation: ecdsa.GenerateKey failed: " + err.Error()) + } + key := newKeyFromECDSA(privateKeyECDSA) + if !strings.HasPrefix(key.Address.Hex(), "0x00") { + return NewKeyForDirectICAP(rand) + } + return key +} + +func newKey(rand io.Reader) (*Key, error) { + privateKeyECDSA, err := ecdsa.GenerateKey(crypto.S256(), rand) + if err != nil { + return nil, err + } + return newKeyFromECDSA(privateKeyECDSA), nil +} + +func storeNewKey(ks keyStore, rand io.Reader, auth string) (*Key, accounts.Account, error) { + key, err := newKey(rand) + if err != nil { + return nil, accounts.Account{}, err + } + a := accounts.Account{ + Address: key.Address, + URL: accounts.URL{Scheme: KeyStoreScheme, Path: ks.JoinPath(keyFileName(key.Address))}, + } + if err := ks.StoreKey(a.URL.Path, key, auth); err != nil { + zeroKey(key.PrivateKey) + return nil, a, err + } + return key, a, err +} + +func writeTemporaryKeyFile(file string, content []byte) (string, error) { + // Create the keystore directory with appropriate permissions + // in case it is not present yet. + const dirPerm = 0700 + if err := os.MkdirAll(filepath.Dir(file), dirPerm); err != nil { + return "", err + } + // Atomic write: create a temporary hidden file first + // then move it into place. TempFile assigns mode 0600. + f, err := ioutil.TempFile(filepath.Dir(file), "."+filepath.Base(file)+".tmp") + if err != nil { + return "", err + } + if _, err := f.Write(content); err != nil { + f.Close() + os.Remove(f.Name()) + return "", err + } + f.Close() + return f.Name(), nil +} + +func writeKeyFile(file string, content []byte) error { + name, err := writeTemporaryKeyFile(file, content) + if err != nil { + return err + } + return os.Rename(name, file) +} + +// keyFileName implements the naming convention for keyfiles: +// UTC--<created_at UTC ISO8601>-<address hex> +func keyFileName(keyAddr common.Address) string { + ts := time.Now().UTC() + return fmt.Sprintf("UTC--%s--%s", toISO8601(ts), hex.EncodeToString(keyAddr[:])) +} + +func toISO8601(t time.Time) string { + var tz string + name, offset := t.Zone() + if name == "UTC" { + tz = "Z" + } else { + tz = fmt.Sprintf("%03d00", offset/3600) + } + return fmt.Sprintf("%04d-%02d-%02dT%02d-%02d-%02d.%09d%s", + t.Year(), t.Month(), t.Day(), t.Hour(), t.Minute(), t.Second(), t.Nanosecond(), tz) +} diff --git a/accounts/keystore/keystore.go b/accounts/keystore/keystore.go new file mode 100644 index 0000000..a3ce33f --- /dev/null +++ b/accounts/keystore/keystore.go @@ -0,0 +1,495 @@ +// 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 keystore implements encrypted storage of secp256k1 private keys. +// +// Keys are stored as encrypted JSON files according to the Web3 Secret Storage specification. +// See https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition for more information. +package keystore + +import ( + "crypto/ecdsa" + crand "crypto/rand" + "errors" + "fmt" + "math/big" + "os" + "path/filepath" + "reflect" + "runtime" + "sync" + "time" + + "github.com/ava-labs/coreth/accounts" + "github.com/ava-labs/coreth/core/types" + "github.com/ava-labs/go-ethereum/common" + "github.com/ava-labs/go-ethereum/crypto" + "github.com/ava-labs/go-ethereum/event" +) + +var ( + ErrLocked = accounts.NewAuthNeededError("password or unlock") + ErrNoMatch = errors.New("no key for given address or file") + ErrDecrypt = errors.New("could not decrypt key with given password") +) + +// KeyStoreType is the reflect type of a keystore backend. +var KeyStoreType = reflect.TypeOf(&KeyStore{}) + +// KeyStoreScheme is the protocol scheme prefixing account and wallet URLs. +const KeyStoreScheme = "keystore" + +// Maximum time between wallet refreshes (if filesystem notifications don't work). +const walletRefreshCycle = 3 * time.Second + +// KeyStore manages a key storage directory on disk. +type KeyStore struct { + storage keyStore // Storage backend, might be cleartext or encrypted + cache *accountCache // In-memory account cache over the filesystem storage + changes chan struct{} // Channel receiving change notifications from the cache + unlocked map[common.Address]*unlocked // Currently unlocked account (decrypted private keys) + + wallets []accounts.Wallet // Wallet wrappers around the individual key files + updateFeed event.Feed // Event feed to notify wallet additions/removals + updateScope event.SubscriptionScope // Subscription scope tracking current live listeners + updating bool // Whether the event notification loop is running + + mu sync.RWMutex +} + +type unlocked struct { + *Key + abort chan struct{} +} + +// NewKeyStore creates a keystore for the given directory. +func NewKeyStore(keydir string, scryptN, scryptP int) *KeyStore { + keydir, _ = filepath.Abs(keydir) + ks := &KeyStore{storage: &keyStorePassphrase{keydir, scryptN, scryptP, false}} + ks.init(keydir) + return ks +} + +// NewPlaintextKeyStore creates a keystore for the given directory. +// Deprecated: Use NewKeyStore. +func NewPlaintextKeyStore(keydir string) *KeyStore { + keydir, _ = filepath.Abs(keydir) + ks := &KeyStore{storage: &keyStorePlain{keydir}} + ks.init(keydir) + return ks +} + +func (ks *KeyStore) init(keydir string) { + // Lock the mutex since the account cache might call back with events + ks.mu.Lock() + defer ks.mu.Unlock() + + // Initialize the set of unlocked keys and the account cache + ks.unlocked = make(map[common.Address]*unlocked) + ks.cache, ks.changes = newAccountCache(keydir) + + // TODO: In order for this finalizer to work, there must be no references + // to ks. addressCache doesn't keep a reference but unlocked keys do, + // so the finalizer will not trigger until all timed unlocks have expired. + runtime.SetFinalizer(ks, func(m *KeyStore) { + m.cache.close() + }) + // Create the initial list of wallets from the cache + accs := ks.cache.accounts() + ks.wallets = make([]accounts.Wallet, len(accs)) + for i := 0; i < len(accs); i++ { + ks.wallets[i] = &keystoreWallet{account: accs[i], keystore: ks} + } +} + +// Wallets implements accounts.Backend, returning all single-key wallets from the +// keystore directory. +func (ks *KeyStore) Wallets() []accounts.Wallet { + // Make sure the list of wallets is in sync with the account cache + ks.refreshWallets() + + ks.mu.RLock() + defer ks.mu.RUnlock() + + cpy := make([]accounts.Wallet, len(ks.wallets)) + copy(cpy, ks.wallets) + return cpy +} + +// refreshWallets retrieves the current account list and based on that does any +// necessary wallet refreshes. +func (ks *KeyStore) refreshWallets() { + // Retrieve the current list of accounts + ks.mu.Lock() + accs := ks.cache.accounts() + + // Transform the current list of wallets into the new one + var ( + wallets = make([]accounts.Wallet, 0, len(accs)) + events []accounts.WalletEvent + ) + + for _, account := range accs { + // Drop wallets while they were in front of the next account + for len(ks.wallets) > 0 && ks.wallets[0].URL().Cmp(account.URL) < 0 { + events = append(events, accounts.WalletEvent{Wallet: ks.wallets[0], Kind: accounts.WalletDropped}) + ks.wallets = ks.wallets[1:] + } + // If there are no more wallets or the account is before the next, wrap new wallet + if len(ks.wallets) == 0 || ks.wallets[0].URL().Cmp(account.URL) > 0 { + wallet := &keystoreWallet{account: account, keystore: ks} + + events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletArrived}) + wallets = append(wallets, wallet) + continue + } + // If the account is the same as the first wallet, keep it + if ks.wallets[0].Accounts()[0] == account { + wallets = append(wallets, ks.wallets[0]) + ks.wallets = ks.wallets[1:] + continue + } + } + // Drop any leftover wallets and set the new batch + for _, wallet := range ks.wallets { + events = append(events, accounts.WalletEvent{Wallet: wallet, Kind: accounts.WalletDropped}) + } + ks.wallets = wallets + ks.mu.Unlock() + + // Fire all wallet events and return + for _, event := range events { + ks.updateFeed.Send(event) + } +} + +// Subscribe implements accounts.Backend, creating an async subscription to +// receive notifications on the addition or removal of keystore wallets. +func (ks *KeyStore) Subscribe(sink chan<- accounts.WalletEvent) event.Subscription { + // We need the mutex to reliably start/stop the update loop + ks.mu.Lock() + defer ks.mu.Unlock() + + // Subscribe the caller and track the subscriber count + sub := ks.updateScope.Track(ks.updateFeed.Subscribe(sink)) + + // Subscribers require an active notification loop, start it + if !ks.updating { + ks.updating = true + go ks.updater() + } + return sub +} + +// updater is responsible for maintaining an up-to-date list of wallets stored in +// the keystore, and for firing wallet addition/removal events. It listens for +// account change events from the underlying account cache, and also periodically +// forces a manual refresh (only triggers for systems where the filesystem notifier +// is not running). |