From f9cbd16f27e393d4937354ee31435e0a2f689484 Mon Sep 17 00:00:00 2001 From: Bas van Kervel Date: Fri, 7 Aug 2015 09:56:49 +0200 Subject: support for user agents --- rpc/useragent/agent.go | 24 +++++++ rpc/useragent/remote_frontend.go | 141 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 165 insertions(+) create mode 100644 rpc/useragent/agent.go create mode 100644 rpc/useragent/remote_frontend.go (limited to 'rpc/useragent') diff --git a/rpc/useragent/agent.go b/rpc/useragent/agent.go new file mode 100644 index 000000000..df0739e65 --- /dev/null +++ b/rpc/useragent/agent.go @@ -0,0 +1,24 @@ +// Copyright 2015 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 . + +// package user agent provides frontends and agents which can interact with the user +package useragent + +var ( + AskPasswordMethod = "agent_askPassword" + ConfirmTransactionMethod = "agent_confirmTransaction" + EnableUserAgentMethod = "admin_enableUserAgent" +) diff --git a/rpc/useragent/remote_frontend.go b/rpc/useragent/remote_frontend.go new file mode 100644 index 000000000..0dd4a6049 --- /dev/null +++ b/rpc/useragent/remote_frontend.go @@ -0,0 +1,141 @@ +// Copyright 2015 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 . + +package useragent + +import ( + "encoding/json" + "fmt" + "net" + + "github.com/ethereum/go-ethereum/accounts" + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/logger" + "github.com/ethereum/go-ethereum/logger/glog" + "github.com/ethereum/go-ethereum/rpc/shared" +) + +// remoteFrontend implements xeth.Frontend and will communicate with an external +// user agent over a connection +type RemoteFrontend struct { + enabled bool + mgr *accounts.Manager + d *json.Decoder + e *json.Encoder + n int +} + +// NewRemoteFrontend creates a new frontend which will interact with an user agent +// over the given connection +func NewRemoteFrontend(conn net.Conn, mgr *accounts.Manager) *RemoteFrontend { + return &RemoteFrontend{false, mgr, json.NewDecoder(conn), json.NewEncoder(conn), 0} +} + +// Enable will enable user interaction +func (fe *RemoteFrontend) Enable() { + fe.enabled = true +} + +// UnlockAccount asks the user agent for the user password and tries to unlock the account. +// It will try 3 attempts before giving up. +func (fe *RemoteFrontend) UnlockAccount(address []byte) bool { + if !fe.enabled { + return false + } + + err := fe.send(AskPasswordMethod, common.Bytes2Hex(address)) + if err != nil { + glog.V(logger.Error).Infof("Unable to send password request to agent - %v\n", err) + return false + } + + passwdRes, err := fe.recv() + if err != nil { + glog.V(logger.Error).Infof("Unable to recv password response from agent - %v\n", err) + return false + } + + if passwd, ok := passwdRes.Result.(string); ok { + err = fe.mgr.Unlock(common.BytesToAddress(address), passwd) + } + + if err == nil { + return true + } + + glog.V(logger.Debug).Infoln("3 invalid account unlock attempts") + return false +} + +// ConfirmTransaction asks the user for approval +func (fe *RemoteFrontend) ConfirmTransaction(tx string) bool { + if !fe.enabled { + return true // backwards compatibility + } + + err := fe.send(ConfirmTransactionMethod, tx) + if err != nil { + glog.V(logger.Error).Infof("Unable to send tx confirmation request to agent - %v\n", err) + return false + } + + confirmResponse, err := fe.recv() + if err != nil { + glog.V(logger.Error).Infof("Unable to recv tx confirmation response from agent - %v\n", err) + return false + } + + if confirmed, ok := confirmResponse.Result.(bool); ok { + return confirmed + } + + return false +} + +// send request to the agent +func (fe *RemoteFrontend) send(method string, params ...interface{}) error { + fe.n += 1 + + p, err := json.Marshal(params) + if err != nil { + glog.V(logger.Info).Infof("Unable to send agent request %v\n", err) + return err + } + + req := shared.Request{ + Method: method, + Jsonrpc: shared.JsonRpcVersion, + Id: fe.n, + Params: p, + } + + return fe.e.Encode(&req) +} + +// recv user response from agent +func (fe *RemoteFrontend) recv() (*shared.SuccessResponse, error) { + var res json.RawMessage + if err := fe.d.Decode(&res); err != nil { + return nil, err + } + + var response shared.SuccessResponse + if err := json.Unmarshal(res, &response); err == nil { + return &response, nil + } + + return nil, fmt.Errorf("Invalid user agent response") +} -- cgit