src/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, 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 package nncp
  19
  20 import (
  21         "bufio"
  22         "bytes"
  23         "compress/zlib"
  24         "fmt"
  25         "io"
  26         "io/ioutil"
  27         "log"
  28         "mime"
  29         "os"
  30         "os/exec"
  31         "path"
  32         "path/filepath"
  33         "strconv"
  34         "strings"
  35
  36         "github.com/davecgh/go-xdr/xdr2"
  37         "github.com/dustin/go-humanize"
  38         "golang.org/x/crypto/blake2b"
  39         "golang.org/x/crypto/poly1305"
  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,
  59 ) bool {
  60         isBad := false
  61         for job := range ctx.Jobs(nodeId, TRx) {
  62                 pktName := filepath.Base(job.Fd.Name())
  63                 sds := SDS{"node": job.PktEnc.Sender, "pkt": pktName}
  64                 if job.PktEnc.Nice > nice {
  65                         ctx.LogD("rx", SdsAdd(sds, SDS{
  66                                 "nice": strconv.Itoa(int(job.PktEnc.Nice)),
  67                         }), "too nice")
  68                         continue
  69                 }
  70                 pipeR, pipeW := io.Pipe()
  71                 errs := make(chan error, 1)
  72                 go func(job Job) {
  73                         pipeWB := bufio.NewWriter(pipeW)
  74                         _, _, err := PktEncRead(
  75                                 ctx.Self,
  76                                 ctx.Neigh,
  77                                 bufio.NewReader(job.Fd),
  78                                 pipeWB,
  79                         )
  80                         errs <- err
  81                         pipeWB.Flush()
  82                         pipeW.Close()
  83                         job.Fd.Close()
  84                         if err != nil {
  85                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "decryption")
  86                         }
  87                 }(job)
  88                 var pkt Pkt
  89                 var err error
  90                 var pktSize int64
  91                 var pktSizeBlocks int64
  92                 if _, err = xdr.Unmarshal(pipeR, &pkt); err != nil {
  93                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "unmarshal")
  94                         isBad = true
  95                         goto Closing
  96                 }
  97                 pktSize = job.Size - PktEncOverhead - PktOverhead - PktSizeOverhead
  98                 pktSizeBlocks = pktSize / (EncBlkSize + poly1305.TagSize)
  99                 if pktSize%(EncBlkSize+poly1305.TagSize) != 0 {
 100                         pktSize -= poly1305.TagSize
 101                 }
 102                 pktSize -= pktSizeBlocks * poly1305.TagSize
 103                 sds["size"] = strconv.FormatInt(pktSize, 10)
 104                 ctx.LogD("rx", sds, "taken")
 105                 switch pkt.Type {
 106                 case PktTypeExec:
 107                         if noExec {
 108                                 goto Closing
 109                         }
 110                         path := bytes.Split(pkt.Path[:int(pkt.PathLen)], []byte{0})
 111                         handle := string(path[0])
 112                         args := make([]string, 0, len(path)-1)
 113                         for _, p := range path[1:] {
 114                                 args = append(args, string(p))
 115                         }
 116                         sds := SdsAdd(sds, SDS{
 117                                 "type": "exec",
 118                                 "dst":  strings.Join(append([]string{handle}, args...), " "),
 119                         })
 120                         decompressor, err := zlib.NewReader(pipeR)
 121                         if err != nil {
 122                                 log.Fatalln(err)
 123                         }
 124                         sender := ctx.Neigh[*job.PktEnc.Sender]
 125                         cmdline, exists := sender.Exec[handle]
 126                         if !exists || len(cmdline) == 0 {
 127                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": "No handle found"}), "")
 128                                 isBad = true
 129                                 goto Closing
 130                         }
 131                         if !dryRun {
 132                                 cmd := exec.Command(
 133                                         cmdline[0],
 134                                         append(cmdline[1:len(cmdline)], args...)...,
 135                                 )
 136                                 cmd.Env = append(
 137                                         cmd.Env,
 138                                         "NNCP_SELF="+ctx.Self.Id.String(),
 139                                         "NNCP_SENDER="+sender.Id.String(),
 140                                         "NNCP_NICE="+strconv.Itoa(int(pkt.Nice)),
 141                                 )
 142                                 cmd.Stdin = decompressor
 143                                 if err = cmd.Run(); err != nil {
 144                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "handle")
 145                                         isBad = true
 146                                         goto Closing
 147                                 }
 148                         }
 149                         ctx.LogI("rx", sds, "")
 150                         if !dryRun {
 151                                 if doSeen {
 152                                         if fd, err := os.Create(job.Fd.Name() + SeenSuffix); err == nil {
 153                                                 fd.Close()
 154                                         }
 155                                 }
 156                                 if err = os.Remove(job.Fd.Name()); err != nil {
 157                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 158                                         isBad = true
 159                                 }
 160                         }
 161                 case PktTypeFile:
 162                         if noFile {
 163                                 goto Closing
 164                         }
 165                         dst := string(pkt.Path[:int(pkt.PathLen)])
 166                         sds := SdsAdd(sds, SDS{"type": "file", "dst": dst})
 167                         if filepath.IsAbs(dst) {
 168                                 ctx.LogE("rx", sds, "non-relative destination path")
 169                                 isBad = true
 170                                 goto Closing
 171                         }
 172                         incoming := ctx.Neigh[*job.PktEnc.Sender].Incoming
 173                         if incoming == nil {
 174                                 ctx.LogE("rx", sds, "incoming is not allowed")
 175                                 isBad = true
 176                                 goto Closing
 177                         }
 178                         dir := filepath.Join(*incoming, path.Dir(dst))
 179                         if err = os.MkdirAll(dir, os.FileMode(0777)); err != nil {
 180                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "mkdir")
 181                                 isBad = true
 182                                 goto Closing
 183                         }
 184                         if !dryRun {
 185                                 tmp, err := TempFile(dir, "file")
 186                                 if err != nil {
 187                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "mktemp")
 188                                         isBad = true
 189                                         goto Closing
 190                                 }
 191                                 sds["tmp"] = tmp.Name()
 192                                 ctx.LogD("rx", sds, "created")
 193                                 bufW := bufio.NewWriter(tmp)
 194                                 if _, err = io.Copy(bufW, pipeR); err != nil {
 195                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "copy")
 196                                         isBad = true
 197                                         goto Closing
 198                                 }
 199                                 if err = bufW.Flush(); err != nil {
 200                                         tmp.Close()
 201                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "copy")
 202                                         isBad = true
 203                                         goto Closing
 204                                 }
 205                                 if err = tmp.Sync(); err != nil {
 206                                         tmp.Close()
 207                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "copy")
 208                                         isBad = true
 209                                         goto Closing
 210                                 }
 211                                 tmp.Close()
 212                                 dstPathOrig := filepath.Join(*incoming, dst)
 213                                 dstPath := dstPathOrig
 214                                 dstPathCtr := 0
 215                                 for {
 216                                         if _, err = os.Stat(dstPath); err != nil {
 217                                                 if os.IsNotExist(err) {
 218                                                         break
 219                                                 }
 220                                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "stat")
 221                                                 isBad = true
 222                                                 goto Closing
 223                                         }
 224                                         dstPath = dstPathOrig + "." + strconv.Itoa(dstPathCtr)
 225                                         dstPathCtr++
 226                                 }
 227                                 if err = os.Rename(tmp.Name(), dstPath); err != nil {
 228                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "rename")
 229                                         isBad = true
 230                                 }
 231                                 delete(sds, "tmp")
 232                         }
 233                         ctx.LogI("rx", sds, "")
 234                         if !dryRun {
 235                                 if doSeen {
 236                                         if fd, err := os.Create(job.Fd.Name() + SeenSuffix); err == nil {
 237                                                 fd.Close()
 238                                         }
 239                                 }
 240                                 if err = os.Remove(job.Fd.Name()); err != nil {
 241                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 242                                         isBad = true
 243                                 }
 244                                 sendmail, exists := ctx.Neigh[*ctx.SelfId].Exec["sendmail"]
 245                                 if exists && len(sendmail) > 0 && ctx.NotifyFile != nil {
 246                                         cmd := exec.Command(
 247                                                 sendmail[0],
 248                                                 append(sendmail[1:len(sendmail)], ctx.NotifyFile.To)...,
 249                                         )
 250                                         cmd.Stdin = newNotification(ctx.NotifyFile, fmt.Sprintf(
 251                                                 "File from %s: %s (%s)",
 252                                                 ctx.Neigh[*job.PktEnc.Sender].Name,
 253                                                 dst,
 254                                                 humanize.IBytes(uint64(pktSize)),
 255                                         ))
 256                                         cmd.Run()
 257                                 }
 258                         }
 259                 case PktTypeFreq:
 260                         if noFreq {
 261                                 goto Closing
 262                         }
 263                         src := string(pkt.Path[:int(pkt.PathLen)])
 264                         if filepath.IsAbs(src) {
 265                                 ctx.LogE("rx", sds, "non-relative source path")
 266                                 isBad = true
 267                                 goto Closing
 268                         }
 269                         sds := SdsAdd(sds, SDS{"type": "freq", "src": src})
 270                         dstRaw, err := ioutil.ReadAll(pipeR)
 271                         if err != nil {
 272                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "read")
 273                                 isBad = true
 274                                 goto Closing
 275                         }
 276                         dst := string(dstRaw)
 277                         sds["dst"] = dst
 278                         sender := ctx.Neigh[*job.PktEnc.Sender]
 279                         freq := sender.Freq
 280                         if freq == nil {
 281                                 ctx.LogE("rx", sds, "freqing is not allowed")
 282                                 isBad = true
 283                                 goto Closing
 284                         }
 285                         if !dryRun {
 286                                 if sender.FreqChunked == 0 {
 287                                         err = ctx.TxFile(
 288                                                 sender,
 289                                                 pkt.Nice,
 290                                                 filepath.Join(*freq, src),
 291                                                 dst,
 292                                                 sender.FreqMinSize,
 293                                         )
 294                                 } else {
 295                                         err = ctx.TxFileChunked(
 296                                                 sender,
 297                                                 pkt.Nice,
 298                                                 filepath.Join(*freq, src),
 299                                                 dst,
 300                                                 sender.FreqMinSize,
 301                                                 sender.FreqChunked,
 302                                         )
 303                                 }
 304                                 if err != nil {
 305                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "tx file")
 306                                         isBad = true
 307                                         goto Closing
 308                                 }
 309                         }
 310                         ctx.LogI("rx", sds, "")
 311                         if !dryRun {
 312                                 if doSeen {
 313                                         if fd, err := os.Create(job.Fd.Name() + SeenSuffix); err == nil {
 314                                                 fd.Close()
 315                                         }
 316                                 }
 317                                 if err = os.Remove(job.Fd.Name()); err != nil {
 318                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 319                                         isBad = true
 320                                 }
 321                                 sendmail, exists := ctx.Neigh[*ctx.SelfId].Exec["sendmail"]
 322                                 if exists && len(sendmail) > 0 && ctx.NotifyFreq != nil {
 323                                         cmd := exec.Command(
 324                                                 sendmail[0],
 325                                                 append(sendmail[1:len(sendmail)], ctx.NotifyFreq.To)...,
 326                                         )
 327                                         cmd.Stdin = newNotification(ctx.NotifyFreq, fmt.Sprintf(
 328                                                 "Freq from %s: %s",
 329                                                 ctx.Neigh[*job.PktEnc.Sender].Name,
 330                                                 src,
 331                                         ))
 332                                         cmd.Run()
 333                                 }
 334                         }
 335                 case PktTypeTrns:
 336                         if noTrns {
 337                                 goto Closing
 338                         }
 339                         dst := new([blake2b.Size256]byte)
 340                         copy(dst[:], pkt.Path[:int(pkt.PathLen)])
 341                         nodeId := NodeId(*dst)
 342                         node, known := ctx.Neigh[nodeId]
 343                         sds := SdsAdd(sds, SDS{"type": "trns", "dst": nodeId})
 344                         if !known {
 345                                 ctx.LogE("rx", sds, "unknown node")
 346                                 isBad = true
 347                                 goto Closing
 348                         }
 349                         ctx.LogD("rx", sds, "taken")
 350                         if !dryRun {
 351                                 if err = ctx.TxTrns(node, job.PktEnc.Nice, pktSize, pipeR); err != nil {
 352                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "tx trns")
 353                                         isBad = true
 354                                         goto Closing
 355                                 }
 356                         }
 357                         ctx.LogI("rx", sds, "")
 358                         if !dryRun {
 359                                 if doSeen {
 360                                         if fd, err := os.Create(job.Fd.Name() + SeenSuffix); err == nil {
 361                                                 fd.Close()
 362                                         }
 363                                 }
 364                                 if err = os.Remove(job.Fd.Name()); err != nil {
 365                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 366                                         isBad = true
 367                                 }
 368                         }
 369                 default:
 370                         ctx.LogE("rx", sds, "unknown type")
 371                         isBad = true
 372                 }
 373         Closing:
 374                 pipeR.Close()
 375         }
 376         return isBad
 377 }