src/cypherpunks.ru/nncp/toss.go

   1 /*
   2 NNCP -- Node to Node copy, utilities for store-and-forward data exchange
   3 Copyright (C) 2016-2019 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 package nncp
  20
  21 import (
  22         "bufio"
  23         "bytes"
  24         "compress/zlib"
  25         "fmt"
  26         "io"
  27         "io/ioutil"
  28         "log"
  29         "mime"
  30         "os"
  31         "os/exec"
  32         "path"
  33         "path/filepath"
  34         "strconv"
  35         "strings"
  36
  37         "github.com/davecgh/go-xdr/xdr2"
  38         "github.com/dustin/go-humanize"
  39         "golang.org/x/crypto/blake2b"
  40 )
  41
  42 const (
  43         SeenSuffix = ".seen"
  44 )
  45
  46 func newNotification(fromTo *FromToYAML, subject string) io.Reader {
  47         return strings.NewReader(fmt.Sprintf(
  48                 "From: %s\nTo: %s\nSubject: %s\n",
  49                 fromTo.From,
  50                 fromTo.To,
  51                 mime.BEncoding.Encode("UTF-8", subject),
  52         ))
  53 }
  54
  55 func (ctx *Ctx) Toss(
  56         nodeId *NodeId,
  57         nice uint8,
  58         dryRun, doSeen, noFile, noFreq, noExec, noTrns bool) bool {
  59         isBad := false
  60         for job := range ctx.Jobs(nodeId, TRx) {
  61                 pktName := filepath.Base(job.Fd.Name())
  62                 sds := SDS{"node": job.PktEnc.Sender, "pkt": pktName}
  63                 if job.PktEnc.Nice > nice {
  64                         ctx.LogD("rx", SdsAdd(sds, SDS{
  65                                 "nice": strconv.Itoa(int(job.PktEnc.Nice)),
  66                         }), "too nice")
  67                         continue
  68                 }
  69                 pipeR, pipeW := io.Pipe()
  70                 errs := make(chan error, 1)
  71                 go func(job Job) {
  72                         pipeWB := bufio.NewWriter(pipeW)
  73                         _, _, err := PktEncRead(
  74                                 ctx.Self,
  75                                 ctx.Neigh,
  76                                 bufio.NewReader(job.Fd),
  77                                 pipeWB,
  78                         )
  79                         errs <- err
  80                         pipeWB.Flush()
  81                         pipeW.Close()
  82                         job.Fd.Close()
  83                         if err != nil {
  84                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "decryption")
  85                         }
  86                 }(job)
  87                 var pkt Pkt
  88                 var err error
  89                 var pktSize int64
  90                 if _, err = xdr.Unmarshal(pipeR, &pkt); err != nil {
  91                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "unmarshal")
  92                         isBad = true
  93                         goto Closing
  94                 }
  95                 pktSize = job.Size - PktEncOverhead - PktOverhead
  96                 sds["size"] = strconv.FormatInt(pktSize, 10)
  97                 ctx.LogD("rx", sds, "taken")
  98                 switch pkt.Type {
  99                 case PktTypeExec:
 100                         if noExec {
 101                                 goto Closing
 102                         }
 103                         path := bytes.Split(pkt.Path[:int(pkt.PathLen)], []byte{0})
 104                         handle := string(path[0])
 105                         args := make([]string, 0, len(path)-1)
 106                         for _, p := range path[1:] {
 107                                 args = append(args, string(p))
 108                         }
 109                         sds := SdsAdd(sds, SDS{
 110                                 "type": "exec",
 111                                 "dst":  strings.Join(append([]string{handle}, args...), " "),
 112                         })
 113                         decompressor, err := zlib.NewReader(pipeR)
 114                         if err != nil {
 115                                 log.Fatalln(err)
 116                         }
 117                         sender := ctx.Neigh[*job.PktEnc.Sender]
 118                         cmdline, exists := sender.Exec[handle]
 119                         if !exists || len(cmdline) == 0 {
 120                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": "No handle found"}), "")
 121                                 isBad = true
 122                                 goto Closing
 123                         }
 124                         if !dryRun {
 125                                 cmd := exec.Command(
 126                                         cmdline[0],
 127                                         append(cmdline[1:len(cmdline)], args...)...,
 128                                 )
 129                                 cmd.Env = append(
 130                                         cmd.Env,
 131                                         "NNCP_SELF="+ctx.Self.Id.String(),
 132                                         "NNCP_SENDER="+sender.Id.String(),
 133                                         "NNCP_NICE="+strconv.Itoa(int(pkt.Nice)),
 134                                 )
 135                                 cmd.Stdin = decompressor
 136                                 if err = cmd.Run(); err != nil {
 137                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "handle")
 138                                         isBad = true
 139                                         goto Closing
 140                                 }
 141                         }
 142                         ctx.LogI("rx", sds, "")
 143                         if !dryRun {
 144                                 if doSeen {
 145                                         if fd, err := os.Create(job.Fd.Name() + SeenSuffix); err == nil {
 146                                                 fd.Close()
 147                                         }
 148                                 }
 149                                 if err = os.Remove(job.Fd.Name()); err != nil {
 150                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 151                                         isBad = true
 152                                 }
 153                         }
 154                 case PktTypeFile:
 155                         if noFile {
 156                                 goto Closing
 157                         }
 158                         dst := string(pkt.Path[:int(pkt.PathLen)])
 159                         sds := SdsAdd(sds, SDS{"type": "file", "dst": dst})
 160                         if filepath.IsAbs(dst) {
 161                                 ctx.LogE("rx", sds, "non-relative destination path")
 162                                 isBad = true
 163                                 goto Closing
 164                         }
 165                         incoming := ctx.Neigh[*job.PktEnc.Sender].Incoming
 166                         if incoming == nil {
 167                                 ctx.LogE("rx", sds, "incoming is not allowed")
 168                                 isBad = true
 169                                 goto Closing
 170                         }
 171                         dir := filepath.Join(*incoming, path.Dir(dst))
 172                         if err = os.MkdirAll(dir, os.FileMode(0700)); err != nil {
 173                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "mkdir")
 174                                 isBad = true
 175                                 goto Closing
 176                         }
 177                         if !dryRun {
 178                                 tmp, err := ioutil.TempFile(dir, "nncp-file")
 179                                 sds["tmp"] = tmp.Name()
 180                                 ctx.LogD("rx", sds, "created")
 181                                 if err != nil {
 182                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "mktemp")
 183                                         isBad = true
 184                                         goto Closing
 185                                 }
 186                                 bufW := bufio.NewWriter(tmp)
 187                                 if _, err = io.Copy(bufW, pipeR); err != nil {
 188                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "copy")
 189                                         isBad = true
 190                                         goto Closing
 191                                 }
 192                                 bufW.Flush()
 193                                 tmp.Sync()
 194                                 tmp.Close()
 195                                 dstPathOrig := filepath.Join(*incoming, dst)
 196                                 dstPath := dstPathOrig
 197                                 dstPathCtr := 0
 198                                 for {
 199                                         if _, err = os.Stat(dstPath); err != nil {
 200                                                 if os.IsNotExist(err) {
 201                                                         break
 202                                                 }
 203                                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "stat")
 204                                                 isBad = true
 205                                                 goto Closing
 206                                         }
 207                                         dstPath = dstPathOrig + strconv.Itoa(dstPathCtr)
 208                                         dstPathCtr++
 209                                 }
 210                                 if err = os.Rename(tmp.Name(), dstPath); err != nil {
 211                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "rename")
 212                                         isBad = true
 213                                 }
 214                                 delete(sds, "tmp")
 215                         }
 216                         ctx.LogI("rx", sds, "")
 217                         if !dryRun {
 218                                 if doSeen {
 219                                         if fd, err := os.Create(job.Fd.Name() + SeenSuffix); err == nil {
 220                                                 fd.Close()
 221                                         }
 222                                 }
 223                                 if err = os.Remove(job.Fd.Name()); err != nil {
 224                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 225                                         isBad = true
 226                                 }
 227                                 sendmail, exists := ctx.Neigh[*ctx.SelfId].Exec["sendmail"]
 228                                 if exists && len(sendmail) > 0 && ctx.NotifyFile != nil {
 229                                         cmd := exec.Command(
 230                                                 sendmail[0],
 231                                                 append(sendmail[1:len(sendmail)], ctx.NotifyFile.To)...,
 232                                         )
 233                                         cmd.Stdin = newNotification(ctx.NotifyFile, fmt.Sprintf(
 234                                                 "File from %s: %s (%s)",
 235                                                 ctx.Neigh[*job.PktEnc.Sender].Name,
 236                                                 dst,
 237                                                 humanize.IBytes(uint64(pktSize)),
 238                                         ))
 239                                         cmd.Run()
 240                                 }
 241                         }
 242                 case PktTypeFreq:
 243                         if noFreq {
 244                                 goto Closing
 245                         }
 246                         src := string(pkt.Path[:int(pkt.PathLen)])
 247                         if filepath.IsAbs(src) {
 248                                 ctx.LogE("rx", sds, "non-relative source path")
 249                                 isBad = true
 250                                 goto Closing
 251                         }
 252                         sds := SdsAdd(sds, SDS{"type": "freq", "src": src})
 253                         dstRaw, err := ioutil.ReadAll(pipeR)
 254                         if err != nil {
 255                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "read")
 256                                 isBad = true
 257                                 goto Closing
 258                         }
 259                         dst := string(dstRaw)
 260                         sds["dst"] = dst
 261                         sender := ctx.Neigh[*job.PktEnc.Sender]
 262                         freq := sender.Freq
 263                         if freq == nil {
 264                                 ctx.LogE("rx", sds, "freqing is not allowed")
 265                                 isBad = true
 266                                 goto Closing
 267                         }
 268                         if !dryRun {
 269                                 if sender.FreqChunked == 0 {
 270                                         err = ctx.TxFile(
 271                                                 sender,
 272                                                 pkt.Nice,
 273                                                 filepath.Join(*freq, src),
 274                                                 dst,
 275                                                 sender.FreqMinSize,
 276                                         )
 277                                 } else {
 278                                         err = ctx.TxFileChunked(
 279                                                 sender,
 280                                                 pkt.Nice,
 281                                                 filepath.Join(*freq, src),
 282                                                 dst,
 283                                                 sender.FreqMinSize,
 284                                                 sender.FreqChunked,
 285                                         )
 286                                 }
 287                                 if err != nil {
 288                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "tx file")
 289                                         isBad = true
 290                                         goto Closing
 291                                 }
 292                         }
 293                         ctx.LogI("rx", sds, "")
 294                         if !dryRun {
 295                                 if doSeen {
 296                                         if fd, err := os.Create(job.Fd.Name() + SeenSuffix); err == nil {
 297                                                 fd.Close()
 298                                         }
 299                                 }
 300                                 if err = os.Remove(job.Fd.Name()); err != nil {
 301                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 302                                         isBad = true
 303                                 }
 304                                 sendmail, exists := ctx.Neigh[*ctx.SelfId].Exec["sendmail"]
 305                                 if exists && len(sendmail) > 0 && ctx.NotifyFreq != nil {
 306                                         cmd := exec.Command(
 307                                                 sendmail[0],
 308                                                 append(sendmail[1:len(sendmail)], ctx.NotifyFreq.To)...,
 309                                         )
 310                                         cmd.Stdin = newNotification(ctx.NotifyFreq, fmt.Sprintf(
 311                                                 "Freq from %s: %s",
 312                                                 ctx.Neigh[*job.PktEnc.Sender].Name,
 313                                                 src,
 314                                         ))
 315                                         cmd.Run()
 316                                 }
 317                         }
 318                 case PktTypeTrns:
 319                         if noTrns {
 320                                 goto Closing
 321                         }
 322                         dst := new([blake2b.Size256]byte)
 323                         copy(dst[:], pkt.Path[:int(pkt.PathLen)])
 324                         nodeId := NodeId(*dst)
 325                         node, known := ctx.Neigh[nodeId]
 326                         sds := SdsAdd(sds, SDS{"type": "trns", "dst": nodeId})
 327                         if !known {
 328                                 ctx.LogE("rx", sds, "unknown node")
 329                                 isBad = true
 330                                 goto Closing
 331                         }
 332                         ctx.LogD("rx", sds, "taken")
 333                         if !dryRun {
 334                                 if err = ctx.TxTrns(node, job.PktEnc.Nice, pktSize, pipeR); err != nil {
 335                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "tx trns")
 336                                         isBad = true
 337                                         goto Closing
 338                                 }
 339                         }
 340                         ctx.LogI("rx", sds, "")
 341                         if !dryRun {
 342                                 if doSeen {
 343                                         if fd, err := os.Create(job.Fd.Name() + SeenSuffix); err == nil {
 344                                                 fd.Close()
 345                                         }
 346                                 }
 347                                 if err = os.Remove(job.Fd.Name()); err != nil {
 348                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 349                                         isBad = true
 350                                 }
 351                         }
 352                 default:
 353                         ctx.LogE("rx", sds, "unknown type")
 354                         isBad = true
 355                 }
 356         Closing:
 357                 pipeR.Close()
 358         }
 359         return isBad
 360 }