poc - simplified initial working version

go.mod

@@ -0,0 +1,8 @@
+module github.com/input-output-hk/vit_ked_qr
+
+go 1.15
+
+require (
+	github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e
+	golang.org/x/crypto v0.0.0-20201012173705-84dcc777aaee
+)

go.sum

@@ -0,0 +1,10 @@
+github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e h1:MRM5ITcdelLK2j1vwZ3Je0FKVCfqOLp5zO6trqMLYs0=
+github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e/go.mod h1:XV66xRDqSt+GTGFMVlhk3ULuV0y9ZmzeVGR4mloJI3M=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20201012173705-84dcc777aaee h1:4yd7jl+vXjalO5ztz6Vc1VADv+S/80LGJmyl1ROJ2AI=
+golang.org/x/crypto v0.0.0-20201012173705-84dcc777aaee/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d h1:+R4KGOnez64A81RvjARKc4UT5/tI9ujCIVX+P5KiHuI=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

main.go

@@ -0,0 +1,149 @@
+//$(which go) run $0 $@; exit $?
+
+package main
+
+import (
+	"encoding/hex"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/input-output-hk/vit_ked_qr/internal/bech32"
+	"github.com/input-output-hk/vit_ked_qr/internal/ked"
+	"github.com/skip2/go-qrcode"
+)
+
+/*
+jcli key to-bytes
+ed25519e_sk14rwkgpmmg5s29e4k8m4mny324lj4rv8x9tqg0tn5khlfqzgjt9ftj90u642j2skwraddf2qd88eqv8wv3a463mshgmz9dxtvthjswgqvcdwty
+a8dd64077b4520a2e6b63eebb9922aafe551b0e62ac087ae74b5fe9009125952b915fcd5552542ce1f5ad4a80d39f2061dcc8f6ba8ee1746c456996c5de50720
+*/
+
+const (
+	PIN_LENGTH = 4             // 4-digit numer
+	KEY_HRP    = "ed25519e_sk" // bech32 hrp of ed25519extended secret key
+	KEY_LENGTH = 64            // bytes of ed25519extended secret key
+)
+
+func main() {
+	var (
+		input  = flag.String("input", "", "path to file containing ed25519extended bech32 value")
+		output = flag.String("output", "", "path to file to save qr code output, if not provided console output will be attempted")
+		pin    = flag.String("pin", "", "Pin code. 4-digit number is used on Catalyst")
+	)
+	flag.Parse()
+
+	/* PIN/PASSWORD check*/
+	password := []byte(strings.TrimSpace(*pin))
+	if len(password) != PIN_LENGTH {
+		fmt.Fprintf(os.Stderr, "%s: needs %d digits, bud %d provided\n", "pin", PIN_LENGTH, len(password))
+		os.Exit(1)
+	}
+	// convert pin/password digits from string to int value
+	for i := range password {
+		s := string(password[i])
+		d, err := strconv.Atoi(s)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "%s: needs %d digits, but non digits detected\n", "pin", PIN_LENGTH)
+			os.Exit(1)
+		}
+		password[i] = byte(d)
+	}
+
+	/* OUTPUT checks */
+	*output = strings.TrimSpace(*output)
+
+	/* INPUT checks */
+	*input = strings.TrimSpace(*input)
+	if *input == "" {
+		fmt.Fprintf(os.Stderr, "flag needs an argument: -%s\n", "input")
+		os.Exit(1)
+	}
+
+	// read input file data
+	fileData, err := ioutil.ReadFile(*input)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s: error reading file %s - [%v]\n", "input", *input, err.Error())
+		os.Exit(1)
+	}
+
+	// convert file data to string
+	inputData := strings.TrimSpace(string(fileData))
+
+	// bech32 decoding and convert to base256 (from base32)
+	hrp, data, err := bech32.DecodeAndConvert(inputData)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s: error %s\n", "bech32.DecodeAndConvert", err.Error())
+		os.Exit(1)
+	}
+
+	// check hrp and key length expectations
+	switch {
+	case hrp != KEY_HRP:
+		fmt.Fprintf(os.Stderr, "%s: error, expected %s, got %s\n", "HRP", KEY_HRP, hrp)
+		os.Exit(1)
+	case len(data) != KEY_LENGTH:
+		fmt.Fprintf(os.Stderr, "%s: error, expected length %d, got %d\n", "KEY", KEY_LENGTH, len(data))
+		os.Exit(1)
+	}
+
+	// encrypt the data
+	encData, err := ked.Encrypt(password, data)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s: error, %s\n", "ked.Encrypt", err.Error())
+		os.Exit(1)
+	}
+
+	// Prepare the qr code with hex encoded data
+	qrData := hex.EncodeToString(encData)
+	qrc, err := qrcode.New(qrData, qrcode.Medium)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s: error, %s\n", "qrcode.New", err.Error())
+		os.Exit(1)
+	}
+
+	if *output != "" {
+		err = qrc.WriteFile(-2, *output) // write to outfut file
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "%s: error, %s\n", "qrc.WriteFile", err.Error())
+			fmt.Printf("\n%s\n", qrc.ToSmallString(false)) // output to console if write to file fails
+		}
+	} else {
+		fmt.Printf("\n%s\n", qrc.ToSmallString(false)) // output to console in no output provided
+	}
+	/* we are done and all the data are outputed */
+
+	/*********************************************************************/
+	/* Perform some reverse checks, encoded data -> original bech32, jic */
+	/*********************************************************************/
+
+	// read hex string data used to build the qr code
+	qrEncData, err := hex.DecodeString(qrData)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s: error, %s\n", "hex.DecodeString", err.Error())
+		os.Exit(1)
+	}
+
+	// decrypt the data
+	qrDecData, err := ked.Decrypt(password, qrEncData)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s: error, %s\n", "ked.Decrypt", err.Error())
+		os.Exit(1)
+	}
+
+	// convert to bech32
+	qrInputData, err := bech32.ConvertAndEncode(KEY_HRP, qrDecData)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s: error, %s\n", "bech32.ConvertAndEncode", err.Error())
+		os.Exit(1)
+	}
+
+	// check if the original bech32 ed25519extended key matches the decrypted output
+	if inputData != qrInputData {
+		fmt.Fprintf(os.Stderr, "Encryption - Decryption checks resulted in missmatch error. The outputs may be corrupted/wrong\n")
+		os.Exit(1)
+	}
+}