github.com/Blockdaemon/celo-blockchain@v0.0.0-20200129231733-e667f6b08419/accounts/accounts.go (about) 1 // Copyright 2017 The go-ethereum Authors 2 // This file is part of the go-ethereum library. 3 // 4 // The go-ethereum library is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU Lesser General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // The go-ethereum library is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU Lesser General Public License for more details. 13 // 14 // You should have received a copy of the GNU Lesser General Public License 15 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. 16 17 // Package accounts implements high level Ethereum account management. 18 package accounts 19 20 import ( 21 "crypto/ecdsa" 22 "math/big" 23 24 ethereum "github.com/ethereum/go-ethereum" 25 "github.com/ethereum/go-ethereum/common" 26 "github.com/ethereum/go-ethereum/core/types" 27 blscrypto "github.com/ethereum/go-ethereum/crypto/bls" 28 "github.com/ethereum/go-ethereum/event" 29 ) 30 31 // Account represents an Ethereum account located at a specific location defined 32 // by the optional URL field. 33 type Account struct { 34 Address common.Address `json:"address"` // Ethereum account address derived from the key 35 URL URL `json:"url"` // Optional resource locator within a backend 36 } 37 38 // Wallet represents a software or hardware wallet that might contain one or more 39 // accounts (derived from the same seed). 40 type Wallet interface { 41 // URL retrieves the canonical path under which this wallet is reachable. It is 42 // user by upper layers to define a sorting order over all wallets from multiple 43 // backends. 44 URL() URL 45 46 // Status returns a textual status to aid the user in the current state of the 47 // wallet. It also returns an error indicating any failure the wallet might have 48 // encountered. 49 Status() (string, error) 50 51 // Open initializes access to a wallet instance. It is not meant to unlock or 52 // decrypt account keys, rather simply to establish a connection to hardware 53 // wallets and/or to access derivation seeds. 54 // 55 // The passphrase parameter may or may not be used by the implementation of a 56 // particular wallet instance. The reason there is no passwordless open method 57 // is to strive towards a uniform wallet handling, oblivious to the different 58 // backend providers. 59 // 60 // Please note, if you open a wallet, you must close it to release any allocated 61 // resources (especially important when working with hardware wallets). 62 Open(passphrase string) error 63 64 // Close releases any resources held by an open wallet instance. 65 Close() error 66 67 // Accounts retrieves the list of signing accounts the wallet is currently aware 68 // of. For hierarchical deterministic wallets, the list will not be exhaustive, 69 // rather only contain the accounts explicitly pinned during account derivation. 70 Accounts() []Account 71 72 // Contains returns whether an account is part of this particular wallet or not. 73 Contains(account Account) bool 74 75 // Decrypt decrypts an ECIES ciphertext. 76 Decrypt(account Account, c, s1, s2 []byte) ([]byte, error) 77 78 // Derive attempts to explicitly derive a hierarchical deterministic account at 79 // the specified derivation path. If requested, the derived account will be added 80 // to the wallet's tracked account list. 81 Derive(path DerivationPath, pin bool) (Account, error) 82 83 // SelfDerive sets a base account derivation path from which the wallet attempts 84 // to discover non zero accounts and automatically add them to list of tracked 85 // accounts. 86 // 87 // Note, self derivaton will increment the last component of the specified path 88 // opposed to decending into a child path to allow discovering accounts starting 89 // from non zero components. 90 // 91 // You can disable automatic account discovery by calling SelfDerive with a nil 92 // chain state reader. 93 SelfDerive(base DerivationPath, chain ethereum.ChainStateReader) 94 95 // SignHash requests the wallet to sign the given hash. 96 // 97 // It looks up the account specified either solely via its address contained within, 98 // or optionally with the aid of any location metadata from the embedded URL field. 99 // 100 // If the wallet requires additional authentication to sign the request (e.g. 101 // a password to decrypt the account, or a PIN code o verify the transaction), 102 // an AuthNeededError instance will be returned, containing infos for the user 103 // about which fields or actions are needed. The user may retry by providing 104 // the needed details via SignHashWithPassphrase, or by other means (e.g. unlock 105 // the account in a keystore). 106 SignHash(account Account, hash []byte) ([]byte, error) 107 SignHashBLS(account Account, hash []byte) (blscrypto.SerializedSignature, error) 108 SignMessageBLS(account Account, msg []byte, extraData []byte) (blscrypto.SerializedSignature, error) 109 GenerateProofOfPossession(account Account, address common.Address) ([]byte, []byte, error) 110 GenerateProofOfPossessionBLS(account Account, address common.Address) ([]byte, []byte, error) 111 GetPublicKey(account Account) (*ecdsa.PublicKey, error) 112 113 // SignTx requests the wallet to sign the given transaction. 114 // 115 // It looks up the account specified either solely via its address contained within, 116 // or optionally with the aid of any location metadata from the embedded URL field. 117 // 118 // If the wallet requires additional authentication to sign the request (e.g. 119 // a password to decrypt the account, or a PIN code to verify the transaction), 120 // an AuthNeededError instance will be returned, containing infos for the user 121 // about which fields or actions are needed. The user may retry by providing 122 // the needed details via SignTxWithPassphrase, or by other means (e.g. unlock 123 // the account in a keystore). 124 SignTx(account Account, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) 125 126 // SignHashWithPassphrase requests the wallet to sign the given hash with the 127 // given passphrase as extra authentication information. 128 // 129 // It looks up the account specified either solely via its address contained within, 130 // or optionally with the aid of any location metadata from the embedded URL field. 131 SignHashWithPassphrase(account Account, passphrase string, hash []byte) ([]byte, error) 132 133 // SignTxWithPassphrase requests the wallet to sign the given transaction, with the 134 // given passphrase as extra authentication information. 135 // 136 // It looks up the account specified either solely via its address contained within, 137 // or optionally with the aid of any location metadata from the embedded URL field. 138 SignTxWithPassphrase(account Account, passphrase string, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) 139 } 140 141 // Backend is a "wallet provider" that may contain a batch of accounts they can 142 // sign transactions with and upon request, do so. 143 type Backend interface { 144 // Wallets retrieves the list of wallets the backend is currently aware of. 145 // 146 // The returned wallets are not opened by default. For software HD wallets this 147 // means that no base seeds are decrypted, and for hardware wallets that no actual 148 // connection is established. 149 // 150 // The resulting wallet list will be sorted alphabetically based on its internal 151 // URL assigned by the backend. Since wallets (especially hardware) may come and 152 // go, the same wallet might appear at a different positions in the list during 153 // subsequent retrievals. 154 Wallets() []Wallet 155 156 // Subscribe creates an async subscription to receive notifications when the 157 // backend detects the arrival or departure of a wallet. 158 Subscribe(sink chan<- WalletEvent) event.Subscription 159 } 160 161 // WalletEventType represents the different event types that can be fired by 162 // the wallet subscription subsystem. 163 type WalletEventType int 164 165 const ( 166 // WalletArrived is fired when a new wallet is detected either via USB or via 167 // a filesystem event in the keystore. 168 WalletArrived WalletEventType = iota 169 170 // WalletOpened is fired when a wallet is successfully opened with the purpose 171 // of starting any background processes such as automatic key derivation. 172 WalletOpened 173 174 // WalletDropped 175 WalletDropped 176 ) 177 178 // WalletEvent is an event fired by an account backend when a wallet arrival or 179 // departure is detected. 180 type WalletEvent struct { 181 Wallet Wallet // Wallet instance arrived or departed 182 Kind WalletEventType // Event type that happened in the system 183 }