src/cmd/nncp-cfgenc/main.go

   1 /*
   2 NNCP -- Node to Node copy, utilities for store-and-forward data exchange
   3 Copyright (C) 2016-2021 Sergey Matveev <stargrave@stargrave.org>
   4
   5 This program is free software: you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation, version 3 of the License.
   8
   9 This program 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 General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 // NNCP configuration file encrypter/decrypter.
  19 package main
  20
  21 import (
  22         "bytes"
  23         "errors"
  24         "flag"
  25         "fmt"
  26         "io/ioutil"
  27         "log"
  28         "os"
  29
  30         xdr "github.com/davecgh/go-xdr/xdr2"
  31         "go.cypherpunks.ru/nncp/v8"
  32         "golang.org/x/crypto/blake2b"
  33         "golang.org/x/term"
  34 )
  35
  36 func usage() {
  37         fmt.Fprintf(os.Stderr, nncp.UsageHeader())
  38         fmt.Fprintf(os.Stderr, "nncp-cfgenc -- encrypt/decrypt configuration file\n\n")
  39         fmt.Fprintf(os.Stderr, "Usage: %s [options] cfg.hjson > cfg.hjson.eblob\n", os.Args[0])
  40         fmt.Fprintf(os.Stderr, "       %s [options] -d cfg.hjson.eblob > cfg.hjson\n", os.Args[0])
  41         fmt.Fprintf(os.Stderr, "       %s [options] -dump cfg.hjson.eblob\n", os.Args[0])
  42         fmt.Fprintln(os.Stderr, "Options:")
  43         flag.PrintDefaults()
  44 }
  45
  46 func main() {
  47         var (
  48                 decrypt  = flag.Bool("d", false, "Decrypt the file")
  49                 dump     = flag.Bool("dump", false, "Print human-readable eblob information")
  50                 sOpt     = flag.Int("s", nncp.DefaultS, "Balloon space cost, in 32 bytes chunks")
  51                 tOpt     = flag.Int("t", nncp.DefaultT, "Balloon time cost, number of rounds")
  52                 pOpt     = flag.Int("p", nncp.DefaultP, "Balloon number of parallel jobs")
  53                 version  = flag.Bool("version", false, "Print version information")
  54                 warranty = flag.Bool("warranty", false, "Print warranty information")
  55         )
  56         log.SetFlags(log.Lshortfile)
  57         flag.Usage = usage
  58         flag.Parse()
  59         if *warranty {
  60                 fmt.Println(nncp.Warranty)
  61                 return
  62         }
  63         if *version {
  64                 fmt.Println(nncp.VersionGet())
  65                 return
  66         }
  67
  68         if flag.NArg() != 1 {
  69                 usage()
  70                 os.Exit(1)
  71         }
  72
  73         data, err := ioutil.ReadFile(flag.Arg(0))
  74         if err != nil {
  75                 log.Fatalln("Can not read data:", err)
  76         }
  77         if *dump {
  78                 var eblob nncp.EBlob
  79                 if _, err := xdr.Unmarshal(bytes.NewReader(data), &eblob); err != nil {
  80                         log.Fatalln(err)
  81                 }
  82                 switch eblob.Magic {
  83                 case nncp.MagicNNCPBv1.B:
  84                         log.Fatalln(nncp.MagicNNCPBv1.TooOld())
  85                 case nncp.MagicNNCPBv2.B:
  86                         log.Fatalln(nncp.MagicNNCPBv2.TooOld())
  87                 case nncp.MagicNNCPBv3.B:
  88                 default:
  89                         log.Fatalln(errors.New("Unknown eblob type"))
  90                 }
  91                 fmt.Println("Strengthening function: Balloon with BLAKE2b-256")
  92                 fmt.Printf("Memory space cost: %d bytes\n", eblob.SCost*blake2b.Size256)
  93                 fmt.Printf("Number of rounds: %d\n", eblob.TCost)
  94                 fmt.Printf("Number of parallel jobs: %d\n", eblob.PCost)
  95                 fmt.Printf("Blob size: %d\n", len(eblob.Blob))
  96                 return
  97         }
  98
  99         os.Stderr.WriteString("Passphrase:")
 100         password1, err := term.ReadPassword(0)
 101         if err != nil {
 102                 log.Fatalln(err)
 103         }
 104         if *decrypt {
 105                 cfgRaw, err := nncp.DeEBlob(data, password1)
 106                 if err != nil {
 107                         log.Fatalln(err)
 108                 }
 109                 os.Stdout.Write(cfgRaw)
 110                 return
 111         }
 112         os.Stderr.WriteString("\nRepeat passphrase:")
 113         password2, err := term.ReadPassword(0)
 114         if err != nil {
 115                 log.Fatalln(err)
 116         }
 117         os.Stderr.WriteString("\n")
 118         if bytes.Compare(password1, password2) != 0 {
 119                 log.Fatalln(errors.New("Passphrases do not match"))
 120         }
 121         eblob, err := nncp.NewEBlob(*sOpt, *tOpt, *pOpt, password1, data)
 122         if err != nil {
 123                 log.Fatalln(err)
 124         }
 125         os.Stdout.Write(eblob)
 126 }