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Diffstat (limited to 'accounts/keystore/key.go')
-rw-r--r-- | accounts/keystore/key.go | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/accounts/keystore/key.go b/accounts/keystore/key.go new file mode 100644 index 000000000..e2bdf09fe --- /dev/null +++ b/accounts/keystore/key.go @@ -0,0 +1,230 @@ +// 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/ethereum/go-ethereum/accounts" + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/crypto" + "github.com/ethereum/go-ethereum/crypto/secp256k1" + "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"` +} + +type scryptParamsJSON struct { + N int `json:"n"` + R int `json:"r"` + P int `json:"p"` + DkLen int `json:"dklen"` + Salt string `json:"salt"` +} + +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 := hex.DecodeString(keyJSON.PrivateKey) + if err != nil { + return err + } + + k.Address = common.BytesToAddress(addr) + k.PrivateKey = crypto.ToECDSA(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(secp256k1.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(secp256k1.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 writeKeyFile(file string, content []byte) 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 os.Rename(f.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) +} |