cmd/clef, signer: initial poc of the standalone signer (#16154)

* signer: introduce external signer command

* cmd/signer, rpc: Implement new signer. Add info about remote user to Context

* signer: refactored request/response, made use of urfave.cli

* cmd/signer: Use common flags

* cmd/signer: methods to validate calldata against abi

* cmd/signer: work on abi parser

* signer: add mutex around UI

* cmd/signer: add json 4byte directory, remove passwords from api

* cmd/signer: minor changes

* cmd/signer: Use ErrRequestDenied, enable lightkdf

* cmd/signer: implement tests

* cmd/signer: made possible for UI to modify tx parameters

* cmd/signer: refactors, removed channels in ui comms, added UI-api via stdin/out

* cmd/signer: Made lowercase json-definitions, added UI-signer test functionality

* cmd/signer: update documentation

* cmd/signer: fix bugs, improve abi detection, abi argument display

* cmd/signer: minor change in json format

* cmd/signer: rework json communication

* cmd/signer: implement mixcase addresses in API, fix json id bug

* cmd/signer: rename fromaccount, update pythonpoc with new json encoding format

* cmd/signer: make use of new abi interface

* signer: documentation

* signer/main: remove redundant  option

* signer: implement audit logging

* signer: create package 'signer', minor changes

* common: add 0x-prefix to mixcaseaddress in json marshalling + validation

* signer, rules, storage: implement rules + ephemeral storage for signer rules

* signer: implement OnApprovedTx, change signing response (API BREAKAGE)

* signer: refactoring + documentation

* signer/rules: implement dispatching to next handler

* signer: docs

* signer/rules: hide json-conversion from users, ensure context is cleaned

* signer: docs

* signer: implement validation rules, change signature of call_info

* signer: fix log flaw with string pointer

* signer: implement custom 4byte databsae that saves submitted signatures

* signer/storage: implement aes-gcm-backed credential storage

* accounts: implement json unmarshalling of url

* signer: fix listresponse, fix gas->uint64

* node: make http/ipc start methods public

* signer: add ipc capability+review concerns

* accounts: correct docstring

* signer: address review concerns

* rpc: go fmt -s

* signer: review concerns+ baptize Clef

* signer,node: move Start-functions to separate file

* signer: formatting

1 files changed, 247 insertions, 0 deletions

diff --git a/signer/core/cliui.go b/signer/core/cliui.go
new file mode 100644
index 000000000..0d9b5f3d3
--- /dev/null
+++ b/signer/core/cliui.go
@@ -0,0 +1,247 @@
+// Copyright 2018 The go-ethereum Authors
+// This file is part of go-ethereum.
+//
+// go-ethereum is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// go-ethereum 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
+package core
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strings"
+
+	"sync"
+
+	"github.com/davecgh/go-spew/spew"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/internal/ethapi"
+	"github.com/ethereum/go-ethereum/log"
+	"golang.org/x/crypto/ssh/terminal"
+)
+
+type CommandlineUI struct {
+	in *bufio.Reader
+	mu sync.Mutex
+}
+
+func NewCommandlineUI() *CommandlineUI {
+	return &CommandlineUI{in: bufio.NewReader(os.Stdin)}
+}
+
+// readString reads a single line from stdin, trimming if from spaces, enforcing
+// non-emptyness.
+func (ui *CommandlineUI) readString() string {
+	for {
+		fmt.Printf("> ")
+		text, err := ui.in.ReadString('\n')
+		if err != nil {
+			log.Crit("Failed to read user input", "err", err)
+		}
+		if text = strings.TrimSpace(text); text != "" {
+			return text
+		}
+	}
+}
+
+// readPassword reads a single line from stdin, trimming it from the trailing new
+// line and returns it. The input will not be echoed.
+func (ui *CommandlineUI) readPassword() string {
+	fmt.Printf("Enter password to approve:\n")
+	fmt.Printf("> ")
+
+	text, err := terminal.ReadPassword(int(os.Stdin.Fd()))
+	if err != nil {
+		log.Crit("Failed to read password", "err", err)
+	}
+	fmt.Println()
+	fmt.Println("-----------------------")
+	return string(text)
+}
+
+// readPassword reads a single line from stdin, trimming it from the trailing new
+// line and returns it. The input will not be echoed.
+func (ui *CommandlineUI) readPasswordText(inputstring string) string {
+	fmt.Printf("Enter %s:\n", inputstring)
+	fmt.Printf("> ")
+	text, err := terminal.ReadPassword(int(os.Stdin.Fd()))
+	if err != nil {
+		log.Crit("Failed to read password", "err", err)
+	}
+	fmt.Println("-----------------------")
+	return string(text)
+}
+
+// confirm returns true if user enters 'Yes', otherwise false
+func (ui *CommandlineUI) confirm() bool {
+	fmt.Printf("Approve? [y/N]:\n")
+	if ui.readString() == "y" {
+		return true
+	}
+	fmt.Println("-----------------------")
+	return false
+}
+
+func showMetadata(metadata Metadata) {
+	fmt.Printf("Request context:\n\t%v -> %v -> %v\n", metadata.Remote, metadata.Scheme, metadata.Local)
+}
+
+// ApproveTx prompt the user for confirmation to request to sign Transaction
+func (ui *CommandlineUI) ApproveTx(request *SignTxRequest) (SignTxResponse, error) {
+	ui.mu.Lock()
+	defer ui.mu.Unlock()
+	weival := request.Transaction.Value.ToInt()
+	fmt.Printf("--------- Transaction request-------------\n")
+	if to := request.Transaction.To; to != nil {
+		fmt.Printf("to:    %v\n", to.Original())
+		if !to.ValidChecksum() {
+			fmt.Printf("\nWARNING: Invalid checksum on to-address!\n\n")
+		}
+	} else {
+		fmt.Printf("to:    <contact creation>\n")
+	}
+	fmt.Printf("from:  %v\n", request.Transaction.From.String())
+	fmt.Printf("value: %v wei\n", weival)
+	if request.Transaction.Data != nil {
+		d := *request.Transaction.Data
+		if len(d) > 0 {
+			fmt.Printf("data:  %v\n", common.Bytes2Hex(d))
+		}
+	}
+	if request.Callinfo != nil {
+		fmt.Printf("\nTransaction validation:\n")
+		for _, m := range request.Callinfo {
+			fmt.Printf("  * %s : %s", m.Typ, m.Message)
+		}
+		fmt.Println()
+
+	}
+	fmt.Printf("\n")
+	showMetadata(request.Meta)
+	fmt.Printf("-------------------------------------------\n")
+	if !ui.confirm() {
+		return SignTxResponse{request.Transaction, false, ""}, nil
+	}
+	return SignTxResponse{request.Transaction, true, ui.readPassword()}, nil
+}
+
+// ApproveSignData prompt the user for confirmation to request to sign data
+func (ui *CommandlineUI) ApproveSignData(request *SignDataRequest) (SignDataResponse, error) {
+	ui.mu.Lock()
+	defer ui.mu.Unlock()
+
+	fmt.Printf("-------- Sign data request--------------\n")
+	fmt.Printf("Account:  %s\n", request.Address.String())
+	fmt.Printf("message:  \n%q\n", request.Message)
+	fmt.Printf("raw data: \n%v\n", request.Rawdata)
+	fmt.Printf("message hash:  %v\n", request.Hash)
+	fmt.Printf("-------------------------------------------\n")
+	showMetadata(request.Meta)
+	if !ui.confirm() {
+		return SignDataResponse{false, ""}, nil
+	}
+	return SignDataResponse{true, ui.readPassword()}, nil
+}
+
+// ApproveExport prompt the user for confirmation to export encrypted Account json
+func (ui *CommandlineUI) ApproveExport(request *ExportRequest) (ExportResponse, error) {
+	ui.mu.Lock()
+	defer ui.mu.Unlock()
+
+	fmt.Printf("-------- Export Account request--------------\n")
+	fmt.Printf("A request has been made to export the (encrypted) keyfile\n")
+	fmt.Printf("Approving this operation means that the caller obtains the (encrypted) contents\n")
+	fmt.Printf("\n")
+	fmt.Printf("Account:  %x\n", request.Address)
+	//fmt.Printf("keyfile:  \n%v\n", request.file)
+	fmt.Printf("-------------------------------------------\n")
+	showMetadata(request.Meta)
+	return ExportResponse{ui.confirm()}, nil
+}
+
+// ApproveImport prompt the user for confirmation to import Account json
+func (ui *CommandlineUI) ApproveImport(request *ImportRequest) (ImportResponse, error) {
+	ui.mu.Lock()
+	defer ui.mu.Unlock()
+
+	fmt.Printf("-------- Import Account request--------------\n")
+	fmt.Printf("A request has been made to import an encrypted keyfile\n")
+	fmt.Printf("-------------------------------------------\n")
+	showMetadata(request.Meta)
+	if !ui.confirm() {
+		return ImportResponse{false, "", ""}, nil
+	}
+	return ImportResponse{true, ui.readPasswordText("Old password"), ui.readPasswordText("New password")}, nil
+}
+
+// ApproveListing prompt the user for confirmation to list accounts
+// the list of accounts to list can be modified by the UI
+func (ui *CommandlineUI) ApproveListing(request *ListRequest) (ListResponse, error) {
+
+	ui.mu.Lock()
+	defer ui.mu.Unlock()
+
+	fmt.Printf("-------- List Account request--------------\n")
+	fmt.Printf("A request has been made to list all accounts. \n")
+	fmt.Printf("You can select which accounts the caller can see\n")
+	for _, account := range request.Accounts {
+		fmt.Printf("\t[x] %v\n", account.Address.Hex())
+	}
+	fmt.Printf("-------------------------------------------\n")
+	showMetadata(request.Meta)
+	if !ui.confirm() {
+		return ListResponse{nil}, nil
+	}
+	return ListResponse{request.Accounts}, nil
+}
+
+// ApproveNewAccount prompt the user for confirmation to create new Account, and reveal to caller
+func (ui *CommandlineUI) ApproveNewAccount(request *NewAccountRequest) (NewAccountResponse, error) {
+
+	ui.mu.Lock()
+	defer ui.mu.Unlock()
+
+	fmt.Printf("-------- New Account request--------------\n")
+	fmt.Printf("A request has been made to create a new. \n")
+	fmt.Printf("Approving this operation means that a new Account is created,\n")
+	fmt.Printf("and the address show to the caller\n")
+	showMetadata(request.Meta)
+	if !ui.confirm() {
+		return NewAccountResponse{false, ""}, nil
+	}
+	return NewAccountResponse{true, ui.readPassword()}, nil
+}
+
+// ShowError displays error message to user
+func (ui *CommandlineUI) ShowError(message string) {
+
+	fmt.Printf("ERROR: %v\n", message)
+}
+
+// ShowInfo displays info message to user
+func (ui *CommandlineUI) ShowInfo(message string) {
+	fmt.Printf("Info: %v\n", message)
+}
+
+func (ui *CommandlineUI) OnApprovedTx(tx ethapi.SignTransactionResult) {
+	fmt.Printf("Transaction signed:\n ")
+	spew.Dump(tx.Tx)
+}
+
+func (ui *CommandlineUI) OnSignerStartup(info StartupInfo) {
+
+	fmt.Printf("------- Signer info -------\n")
+	for k, v := range info.Info {
+		fmt.Printf("* %v : %v\n", k, v)
+	}
+}