src/cypherpunks.ru/nncp/toss.go

   1 /*
   2 NNCP -- Node to Node copy, utilities for store-and-forward data exchange
   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 package nncp
  20
  21 import (
  22         "bufio"
  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/sys/unix"
  40 )
  41
  42 func newNotification(fromTo *FromToYAML, subject string) io.Reader {
  43         return strings.NewReader(fmt.Sprintf(
  44                 "From: %s\nTo: %s\nSubject: %s\n",
  45                 fromTo.From,
  46                 fromTo.To,
  47                 mime.BEncoding.Encode("UTF-8", subject),
  48         ))
  49 }
  50
  51 func (ctx *Ctx) LockDir(nodeId *NodeId, xx TRxTx) (*os.File, error) {
  52         ctx.ensureRxDir(nodeId)
  53         lockPath := filepath.Join(ctx.Spool, nodeId.String(), string(xx)) + ".lock"
  54         dirLock, err := os.OpenFile(
  55                 lockPath,
  56                 os.O_CREATE|os.O_WRONLY,
  57                 os.FileMode(0600),
  58         )
  59         if err != nil {
  60                 ctx.LogE("lockdir", SDS{"path": lockPath, "err": err}, "")
  61                 return nil, err
  62         }
  63         err = unix.Flock(int(dirLock.Fd()), unix.LOCK_EX|unix.LOCK_NB)
  64         if err != nil {
  65                 ctx.LogE("lockdir", SDS{"path": lockPath, "err": err}, "")
  66                 dirLock.Close()
  67                 return nil, err
  68         }
  69         return dirLock, nil
  70 }
  71
  72 func (ctx *Ctx) UnlockDir(fd *os.File) {
  73         if fd != nil {
  74                 unix.Flock(int(fd.Fd()), unix.LOCK_UN)
  75                 fd.Close()
  76         }
  77 }
  78
  79 func (ctx *Ctx) Toss(nodeId *NodeId, nice uint8, dryRun bool) bool {
  80         dirLock, err := ctx.LockDir(nodeId, TRx)
  81         if err != nil {
  82                 return false
  83         }
  84         defer ctx.UnlockDir(dirLock)
  85         isBad := false
  86         for job := range ctx.Jobs(nodeId, TRx) {
  87                 pktName := filepath.Base(job.Fd.Name())
  88                 sds := SDS{"node": job.PktEnc.Sender, "pkt": pktName}
  89                 if job.PktEnc.Nice > nice {
  90                         ctx.LogD("rx", SdsAdd(sds, SDS{
  91                                 "nice": strconv.Itoa(int(job.PktEnc.Nice)),
  92                         }), "too nice")
  93                         continue
  94                 }
  95                 pipeR, pipeW := io.Pipe()
  96                 errs := make(chan error, 1)
  97                 go func(job Job) {
  98                         pipeWB := bufio.NewWriter(pipeW)
  99                         _, _, err := PktEncRead(
 100                                 ctx.Self,
 101                                 ctx.Neigh,
 102                                 bufio.NewReader(job.Fd),
 103                                 pipeWB,
 104                         )
 105                         errs <- err
 106                         pipeWB.Flush()
 107                         pipeW.Close()
 108                         job.Fd.Close()
 109                         if err != nil {
 110                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "decryption")
 111                         }
 112                 }(job)
 113                 var pkt Pkt
 114                 var err error
 115                 var pktSize int64
 116                 if _, err = xdr.Unmarshal(pipeR, &pkt); err != nil {
 117                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "unmarshal")
 118                         isBad = true
 119                         goto Closing
 120                 }
 121                 pktSize = job.Size - PktEncOverhead - PktOverhead
 122                 sds["size"] = strconv.FormatInt(pktSize, 10)
 123                 ctx.LogD("rx", sds, "taken")
 124                 switch pkt.Type {
 125                 case PktTypeMail:
 126                         recipients := string(pkt.Path[:int(pkt.PathLen)])
 127                         sds := SdsAdd(sds, SDS{
 128                                 "type": "mail",
 129                                 "dst":  recipients,
 130                         })
 131                         decompressor, err := zlib.NewReader(pipeR)
 132                         if err != nil {
 133                                 log.Fatalln(err)
 134                         }
 135                         sendmail := ctx.Neigh[*job.PktEnc.Sender].Sendmail
 136                         if len(sendmail) == 0 {
 137                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": "No sendmail configured"}), "")
 138                                 isBad = true
 139                                 goto Closing
 140                         }
 141                         if !dryRun {
 142                                 cmd := exec.Command(
 143                                         sendmail[0],
 144                                         append(
 145                                                 sendmail[1:len(sendmail)],
 146                                                 strings.Split(recipients, " ")...,
 147                                         )...,
 148                                 )
 149                                 cmd.Stdin = decompressor
 150                                 if err = cmd.Run(); err != nil {
 151                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "sendmail")
 152                                         isBad = true
 153                                         goto Closing
 154                                 }
 155                         }
 156                         ctx.LogI("rx", sds, "")
 157                         if !dryRun {
 158                                 if err = os.Remove(job.Fd.Name()); err != nil {
 159                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 160                                         isBad = true
 161                                 }
 162                         }
 163                 case PktTypeFile:
 164                         dst := string(pkt.Path[:int(pkt.PathLen)])
 165                         sds := SdsAdd(sds, SDS{"type": "file", "dst": dst})
 166                         incoming := ctx.Neigh[*job.PktEnc.Sender].Incoming
 167                         if incoming == nil {
 168                                 ctx.LogE("rx", sds, "incoming is not allowed")
 169                                 isBad = true
 170                                 goto Closing
 171                         }
 172                         dir := filepath.Join(*incoming, path.Dir(dst))
 173                         if err = os.MkdirAll(dir, os.FileMode(0700)); err != nil {
 174                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "mkdir")
 175                                 isBad = true
 176                                 goto Closing
 177                         }
 178                         if !dryRun {
 179                                 tmp, err := ioutil.TempFile(dir, "nncp-file")
 180                                 sds["tmp"] = tmp.Name()
 181                                 ctx.LogD("rx", sds, "created")
 182                                 if err != nil {
 183                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "mktemp")
 184                                         isBad = true
 185                                         goto Closing
 186                                 }
 187                                 bufW := bufio.NewWriter(tmp)
 188                                 if _, err = io.Copy(bufW, pipeR); err != nil {
 189                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "copy")
 190                                         isBad = true
 191                                         goto Closing
 192                                 }
 193                                 bufW.Flush()
 194                                 tmp.Sync()
 195                                 tmp.Close()
 196                                 dstPathOrig := filepath.Join(*incoming, dst)
 197                                 dstPath := dstPathOrig
 198                                 dstPathCtr := 0
 199                                 for {
 200                                         if _, err = os.Stat(dstPath); err != nil {
 201                                                 if os.IsNotExist(err) {
 202                                                         break
 203                                                 }
 204                                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "stat")
 205                                                 isBad = true
 206                                                 goto Closing
 207                                         }
 208                                         dstPath = dstPathOrig + strconv.Itoa(dstPathCtr)
 209                                         dstPathCtr++
 210                                 }
 211                                 if err = os.Rename(tmp.Name(), dstPath); err != nil {
 212                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "rename")
 213                                         isBad = true
 214                                 }
 215                                 delete(sds, "tmp")
 216                         }
 217                         ctx.LogI("rx", sds, "")
 218                         if !dryRun {
 219                                 if err = os.Remove(job.Fd.Name()); err != nil {
 220                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 221                                         isBad = true
 222                                 }
 223                                 sendmail := ctx.Neigh[*ctx.SelfId].Sendmail
 224                                 if ctx.NotifyFile != nil {
 225                                         cmd := exec.Command(
 226                                                 sendmail[0],
 227                                                 append(sendmail[1:len(sendmail)], ctx.NotifyFile.To)...,
 228                                         )
 229                                         cmd.Stdin = newNotification(ctx.NotifyFile, fmt.Sprintf(
 230                                                 "File from %s: %s (%s)",
 231                                                 ctx.Neigh[*job.PktEnc.Sender].Name,
 232                                                 dst,
 233                                                 humanize.IBytes(uint64(pktSize)),
 234                                         ))
 235                                         cmd.Run()
 236                                 }
 237                         }
 238                 case PktTypeFreq:
 239                         src := string(pkt.Path[:int(pkt.PathLen)])
 240                         sds := SdsAdd(sds, SDS{"type": "freq", "src": src})
 241                         dstRaw, err := ioutil.ReadAll(pipeR)
 242                         if err != nil {
 243                                 ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "read")
 244                                 isBad = true
 245                                 goto Closing
 246                         }
 247                         dst := string(dstRaw)
 248                         sds["dst"] = dst
 249                         sender := ctx.Neigh[*job.PktEnc.Sender]
 250                         freq := sender.Freq
 251                         if freq == nil {
 252                                 ctx.LogE("rx", sds, "freqing is not allowed")
 253                                 isBad = true
 254                                 goto Closing
 255                         }
 256                         if !dryRun {
 257                                 if err = ctx.TxFile(sender, job.PktEnc.Nice, filepath.Join(*freq, src), dst, 0); err != nil {
 258                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "tx file")
 259                                         isBad = true
 260                                         goto Closing
 261                                 }
 262                         }
 263                         ctx.LogI("rx", sds, "")
 264                         if !dryRun {
 265                                 if err = os.Remove(job.Fd.Name()); err != nil {
 266                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 267                                         isBad = true
 268                                 }
 269                                 if ctx.NotifyFreq != nil {
 270                                         sendmail := ctx.Neigh[*ctx.SelfId].Sendmail
 271                                         cmd := exec.Command(
 272                                                 sendmail[0],
 273                                                 append(sendmail[1:len(sendmail)], ctx.NotifyFreq.To)...,
 274                                         )
 275                                         cmd.Stdin = newNotification(ctx.NotifyFreq, fmt.Sprintf(
 276                                                 "Freq from %s: %s",
 277                                                 ctx.Neigh[*job.PktEnc.Sender].Name,
 278                                                 src,
 279                                         ))
 280                                         cmd.Run()
 281                                 }
 282                         }
 283                 case PktTypeTrns:
 284                         dst := new([blake2b.Size256]byte)
 285                         copy(dst[:], pkt.Path[:int(pkt.PathLen)])
 286                         nodeId := NodeId(*dst)
 287                         node, known := ctx.Neigh[nodeId]
 288                         sds := SdsAdd(sds, SDS{"type": "trns", "dst": nodeId})
 289                         if !known {
 290                                 ctx.LogE("rx", sds, "unknown node")
 291                                 isBad = true
 292                                 goto Closing
 293                         }
 294                         ctx.LogD("rx", sds, "taken")
 295                         if !dryRun {
 296                                 if err = ctx.TxTrns(node, job.PktEnc.Nice, pktSize, pipeR); err != nil {
 297                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "tx trns")
 298                                         isBad = true
 299                                         goto Closing
 300                                 }
 301                         }
 302                         ctx.LogI("rx", sds, "")
 303                         if !dryRun {
 304                                 if err = os.Remove(job.Fd.Name()); err != nil {
 305                                         ctx.LogE("rx", SdsAdd(sds, SDS{"err": err}), "remove")
 306                                         isBad = true
 307                                 }
 308                         }
 309                 default:
 310                         ctx.LogE("rx", sds, "unknown type")
 311                         isBad = true
 312                 }
 313         Closing:
 314                 pipeR.Close()
 315         }
 316         return isBad
 317 }