src/cypherpunks.ru/nncp/cmd/nncp-pkt/main.go

   1 /*
   2 NNCP -- Node-to-Node CoPy
   3 Copyright (C) 2016-2017 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, either version 3 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 // Parse raw NNCP packet
  20 package main
  21
  22 import (
  23         "bufio"
  24         "bytes"
  25         "flag"
  26         "fmt"
  27         "io"
  28         "io/ioutil"
  29         "log"
  30         "os"
  31
  32         "cypherpunks.ru/nncp"
  33         "github.com/davecgh/go-xdr/xdr2"
  34         "github.com/dustin/go-humanize"
  35         "golang.org/x/crypto/blake2b"
  36 )
  37
  38 func usage() {
  39         fmt.Fprintf(os.Stderr, nncp.UsageHeader())
  40         fmt.Fprintln(os.Stderr, "nncp-pkt -- parse raw packet\n")
  41         fmt.Fprintln(os.Stderr, "Usage: %s [options]\nOptions:", os.Args[0])
  42         flag.PrintDefaults()
  43         fmt.Fprintln(os.Stderr, "Packet is read from stdin.")
  44 }
  45
  46 func main() {
  47         var (
  48                 dump     = flag.Bool("dump", false, "Write decrypted/parsed payload to stdout")
  49                 cfgPath  = flag.String("cfg", nncp.DefaultCfgPath, "Path to configuration file")
  50                 version  = flag.Bool("version", false, "Print version information")
  51                 warranty = flag.Bool("warranty", false, "Print warranty information")
  52         )
  53         flag.Usage = usage
  54         flag.Parse()
  55         if *warranty {
  56                 fmt.Println(nncp.Warranty)
  57                 return
  58         }
  59         if *version {
  60                 fmt.Println(nncp.VersionGet())
  61                 return
  62         }
  63
  64         var err error
  65         beginning := make([]byte, nncp.PktOverhead-blake2b.Size256)
  66         if _, err = io.ReadFull(os.Stdin, beginning); err != nil {
  67                 log.Fatalln("Not enough data to read")
  68         }
  69         var pkt nncp.Pkt
  70         _, err = xdr.Unmarshal(bytes.NewReader(beginning), &pkt)
  71         if err == nil && pkt.Magic == nncp.MagicNNCPPv1 {
  72                 if *dump {
  73                         bufW := bufio.NewWriter(os.Stdout)
  74                         if _, err = io.Copy(bufW, bufio.NewReader(os.Stdin)); err != nil {
  75                                 log.Fatalln(err)
  76                         }
  77                         if err = bufW.Flush(); err != nil {
  78                                 log.Fatalln(err)
  79                         }
  80                         return
  81                 }
  82                 payloadType := "unknown"
  83                 switch pkt.Type {
  84                 case nncp.PktTypeFile:
  85                         payloadType = "file"
  86                 case nncp.PktTypeFreq:
  87                         payloadType = "file request"
  88                 case nncp.PktTypeMail:
  89                         payloadType = "mail"
  90                 case nncp.PktTypeTrns:
  91                         payloadType = "transitional"
  92                 }
  93                 var path string
  94                 switch pkt.Type {
  95                 case nncp.PktTypeTrns:
  96                         path = nncp.ToBase32(pkt.Path[:pkt.PathLen])
  97                 default:
  98                         path = string(pkt.Path[:pkt.PathLen])
  99                 }
 100                 fmt.Printf("Packet type: plain\nPayload type: %s\nPath: %s\n", payloadType, path)
 101                 return
 102         }
 103         var pktEnc nncp.PktEnc
 104         _, err = xdr.Unmarshal(bytes.NewReader(beginning), &pktEnc)
 105         if err == nil && pktEnc.Magic == nncp.MagicNNCPEv1 {
 106                 if *dump {
 107                         cfgRaw, err := ioutil.ReadFile(*cfgPath)
 108                         if err != nil {
 109                                 log.Fatalln("Can not read config:", err)
 110                         }
 111                         ctx, err := nncp.CfgParse(cfgRaw)
 112                         if err != nil {
 113                                 log.Fatalln("Can not parse config:", err)
 114                         }
 115                         bufW := bufio.NewWriter(os.Stdout)
 116                         if _, err = nncp.PktEncRead(
 117                                 ctx.Self,
 118                                 ctx.Neigh,
 119                                 io.MultiReader(
 120                                         bytes.NewReader(beginning),
 121                                         bufio.NewReader(os.Stdin),
 122                                 ),
 123                                 bufW,
 124                         ); err != nil {
 125                                 log.Fatalln(err)
 126                         }
 127                         if err = bufW.Flush(); err != nil {
 128                                 log.Fatalln(err)
 129                         }
 130                         return
 131                 }
 132                 fmt.Printf(
 133                         "Packet type: encrypted\nNiceness: %d\nSender: %s\nPayload size: %s (%d bytes)\n",
 134                         pktEnc.Nice, pktEnc.Sender, humanize.IBytes(pktEnc.Size), pktEnc.Size,
 135                 )
 136                 return
 137         }
 138         log.Fatalln("Unable to determine packet type")
 139 }