sshmount 0.3.2

Mount the directory to which the ssh connection is made.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
mod bi_hash_map;
mod file_handle;
mod inode;

use file_handle::Fhandles;
use inode::Inodes;

use anyhow::Context;
use fuser::{FileAttr, Filesystem, ReplyAttr, ReplyData, ReplyDirectory, ReplyEntry, Request};
use libc::ENOENT;
use log::{debug, error, warn};
use ssh2::{ErrorCode, OpenFlags, OpenType, Session, Sftp};
use std::{
    ffi::OsStr,
    io::{Read, Seek, SeekFrom, Write},
    path::{Path, PathBuf},
    time::{Duration, SystemTime, UNIX_EPOCH},
};

/// FUSE ファイルシステム実装
pub struct Sshfs {
    _session: Session,
    sftp: Sftp,
    inodes: Inodes,
    fhandls: Fhandles,
    _top_path: PathBuf,
}

impl Sshfs {
    pub fn new<P: AsRef<Path>>(session: Session, path: P) -> anyhow::Result<Self> {
        let mut inodes = Inodes::new();
        let top_path: PathBuf = path.as_ref().into();
        inodes.add(&top_path);
        let sftp = session
            .sftp()
            .inspect_err(|_| {
                error!("Failed to create sftp from session.");
            })
            .context("Failed to create sftp from session.(Sshfs::new)")?;
        debug!(
            "[Sshfs::new] connect path: <{:?}>, inodes=<{:?}>",
            &top_path, &inodes
        );
        Ok(Self {
            _session: session,
            sftp,
            inodes,
            fhandls: Fhandles::new(),
            _top_path: top_path,
        })
    }

    /// ssh2経由でファイルのステータスを取得する。
    /// 副作用:取得に成功した場合、inodesにパスを登録する。
    fn getattr_from_ssh2(&mut self, path: &Path, uid: u32, gid: u32) -> Result<FileAttr, Error> {
        let attr_ssh2 = self.sftp.lstat(path)?;
        let kind = Self::conv_file_kind_ssh2fuser(&attr_ssh2.file_type())?;
        let ino = self.inodes.add(path);
        Ok(FileAttr {
            ino,
            size: attr_ssh2.size.unwrap_or(0),
            blocks: attr_ssh2.size.unwrap_or(0) / 512 + 1,
            atime: UNIX_EPOCH + Duration::from_secs(attr_ssh2.atime.unwrap_or(0)),
            mtime: UNIX_EPOCH + Duration::from_secs(attr_ssh2.mtime.unwrap_or(0)),
            ctime: UNIX_EPOCH + Duration::from_secs(attr_ssh2.mtime.unwrap_or(0)),
            crtime: UNIX_EPOCH,
            kind,
            perm: attr_ssh2.perm.unwrap_or(0o666) as u16,
            nlink: 1,
            uid,
            gid,
            rdev: 0,
            blksize: 512,
            flags: 0,
        })
    }

    fn conv_file_kind_ssh2fuser(filetype: &ssh2::FileType) -> Result<fuser::FileType, Error> {
        match filetype {
            ssh2::FileType::NamedPipe => Ok(fuser::FileType::NamedPipe),
            ssh2::FileType::CharDevice => Ok(fuser::FileType::CharDevice),
            ssh2::FileType::BlockDevice => Ok(fuser::FileType::BlockDevice),
            ssh2::FileType::Directory => Ok(fuser::FileType::Directory),
            ssh2::FileType::RegularFile => Ok(fuser::FileType::RegularFile),
            ssh2::FileType::Symlink => Ok(fuser::FileType::Symlink),
            ssh2::FileType::Socket => Ok(fuser::FileType::Socket),
            ssh2::FileType::Other(_) => Err(Error(libc::EBADF)),
        }
    }

    fn conv_timeornow2systemtime(time: &fuser::TimeOrNow) -> SystemTime {
        match time {
            fuser::TimeOrNow::SpecificTime(t) => *t,
            fuser::TimeOrNow::Now => SystemTime::now(),
        }
    }
}

impl Filesystem for Sshfs {
    fn lookup(&mut self, req: &Request, parent: u64, name: &OsStr, reply: ReplyEntry) {
        debug!("[lookup] start: parent={}, name={:?}", parent, name);
        let Some(mut path) = self.inodes.get_path(parent) else {
            debug!("[lookup] 親ディレクトリの検索に失敗 inode={}", parent);
            reply.error(ENOENT);
            return;
        };
        path.push(Path::new(name));
        match self.getattr_from_ssh2(&path, req.uid(), req.gid()) {
            Ok(attr) => reply.entry(&Duration::from_secs(1), &attr, 0),
            Err(e) => {
                reply.error(e.0);
            }
        };
    }

    fn getattr(&mut self, req: &Request, ino: u64, _fh: Option<u64>, reply: ReplyAttr) {
        debug!("[getattr] start: ino={}", ino);
        let Some(path) = self.inodes.get_path(ino) else {
            debug!("[getattr] path取得失敗: inode={}", ino);
            reply.error(ENOENT);
            return;
        };
        match self.getattr_from_ssh2(&path, req.uid(), req.gid()) {
            Ok(attr) => {
                //debug!("[getattr]retrun attr: {:?}", &attr);
                reply.attr(&Duration::from_secs(1), &attr);
            }
            Err(e) => {
                warn!("[getattr] getattr_from_ssh2エラー: {:?}", &e);
                reply.error(e.0)
            }
        };
    }

    fn readdir(
        &mut self,
        _req: &Request,
        ino: u64,
        _fh: u64,
        offset: i64,
        mut reply: ReplyDirectory,
    ) {
        debug!("[readdir] start: ino={}, offset={}", ino, offset);
        let Some(path) = self.inodes.get_path(ino) else {
            reply.error(libc::ENOENT);
            return;
        };
        match self.sftp.readdir(&path) {
            Ok(mut dir) => {
                let cur_file_attr = ssh2::FileStat {
                    size: None,
                    uid: None,
                    gid: None,
                    perm: Some(libc::S_IFDIR),
                    atime: None,
                    mtime: None,
                }; // "." ".."の解決用。 attr ディレクトリであることのみを示す。
                dir.insert(0, (Path::new("..").into(), cur_file_attr.clone()));
                dir.insert(0, (Path::new(".").into(), cur_file_attr));
                let mut i = offset + 1;
                for f in dir.iter().skip(offset as usize) {
                    let ino = if f.0 == Path::new("..") || f.0 == Path::new(".") {
                        1
                    } else {
                        self.inodes.add(&f.0)
                    };
                    let name = match f.0.file_name() {
                        Some(n) => n,
                        None => f.0.as_os_str(),
                    };
                    let filetype = &f.1.file_type();
                    let filetype = match Self::conv_file_kind_ssh2fuser(filetype) {
                        Ok(t) => t,
                        Err(e) => {
                            warn!(
                                "[readdir]ファイルタイプ解析失敗: inode={}, name={:?}",
                                ino, name
                            );
                            reply.error(e.0);
                            return;
                        }
                    };
                    if reply.add(ino, i, filetype, name) {
                        break;
                    }
                    i += 1;
                }
                reply.ok();
            }
            Err(e) => {
                warn!("[readdir]ssh2::readdir内でエラー発生-- {:?}", e);
                reply.error(Error::from(e).0);
            }
        };
    }

    fn readlink(&mut self, _req: &Request<'_>, ino: u64, reply: ReplyData) {
        debug!("[readlink] start: ino={}", ino);
        let Some(path) = self.inodes.get_path(ino) else {
            error!("[readlink] 親ディレクトリの検索に失敗 {ino}");
            reply.error(libc::ENOENT);
            return;
        };
        match self.sftp.readlink(&path) {
            Ok(p) => {
                //debug!("[readlink] ret_path => {:?}", &p);
                reply.data(p.as_os_str().to_string_lossy().as_bytes());
            }
            Err(e) => {
                //debug!("[readlink] ssh2::readlink error => {e:?}");
                reply.error(Error::from(e).0);
            }
        }
    }

    fn open(&mut self, _req: &Request<'_>, ino: u64, flags: i32, reply: fuser::ReplyOpen) {
        debug!("[open] start: ino={}, flags={:x}", ino, flags);
        let Some(file_name) = self.inodes.get_path(ino) else {
            reply.error(libc::ENOENT);
            return;
        };

        let mut flags_ssh2 = OpenFlags::empty();
        if flags & libc::O_WRONLY != 0 {
            flags_ssh2.insert(OpenFlags::WRITE);
        } else if flags & libc::O_RDWR != 0 {
            flags_ssh2.insert(OpenFlags::READ);
            flags_ssh2.insert(OpenFlags::WRITE);
        } else {
            flags_ssh2.insert(OpenFlags::READ);
        }
        if flags & libc::O_APPEND != 0 {
            flags_ssh2.insert(OpenFlags::APPEND);
        }
        if flags & libc::O_CREAT != 0 {
            flags_ssh2.insert(OpenFlags::CREATE);
        }
        if flags & libc::O_TRUNC != 0 {
            flags_ssh2.insert(OpenFlags::TRUNCATE);
        }
        if flags & libc::O_EXCL != 0 {
            flags_ssh2.insert(OpenFlags::EXCLUSIVE);
        }

        debug!(
            "[open] filename='{:?}', openflag = {:?}, bit = {:x}",
            &file_name,
            &flags_ssh2,
            flags_ssh2.bits()
        );
        match self
            .sftp
            .open_mode(&file_name, flags_ssh2, 0o777, ssh2::OpenType::File)
        {
            Ok(file) => {
                let fh = self.fhandls.add_file(file);
                reply.opened(fh, flags as u32);
            }
            Err(e) => {
                log::error!(
                    "file-open error: filename='{:?}', mode={:?}, err={}",
                    &file_name,
                    &flags_ssh2,
                    &e
                );
                reply.error(Error::from(e).0);
            }
        }
    }

    fn release(
        &mut self,
        _req: &Request<'_>,
        _ino: u64,
        fh: u64,
        _flags: i32,
        _lock_owner: Option<u64>,
        _flush: bool,
        reply: fuser::ReplyEmpty,
    ) {
        debug!("[release] start: fh={}", fh);
        self.fhandls.del_file(fh);
        reply.ok();
    }

    fn read(
        &mut self,
        _req: &Request,
        _ino: u64,
        fh: u64,
        offset: i64,
        size: u32,
        _flags: i32,
        _lock_owner: Option<u64>,
        reply: ReplyData,
    ) {
        debug!("[read] start: fh={}, offset={}, size={}", fh, offset, size);
        let Some(file_mutex) = self.fhandls.get_file(fh) else {
            reply.error(libc::EBADF);
            return;
        };
        let mut file = file_mutex.lock().unwrap();
        // 注釈:このデータの出所であるFhandles構造体内のデータに毒化があるということは、
        // システム全域の他のファイルハンドルの正当性も保証できないことを意味する。
        // ファイル操作を失敗させることより、システム全体を落とすことが正しい選択と思われる。
        // よって、lock().unwrap()とする。write()関数他においても同様。

        if let Err(e) = file.seek(std::io::SeekFrom::Start(offset as u64)) {
            reply.error(Error::from(e).0);
            return;
        }
        let mut buff = vec![0; size as usize];
        let mut read_size: usize = 0;
        while read_size < size as usize {
            match file.read(&mut buff[read_size..]) {
                Ok(s) => {
                    if s == 0 {
                        break;
                    };
                    read_size += s;
                }
                Err(e) => {
                    reply.error(Error::from(e).0);
                    return;
                }
            }
        }
        buff.resize(read_size, 0u8);
        reply.data(&buff);
    }

    fn write(
        &mut self,
        _req: &Request<'_>,
        _ino: u64,
        fh: u64,
        offset: i64,
        data: &[u8],
        _write_flags: u32,
        _flags: i32,
        _lock_owner: Option<u64>,
        reply: fuser::ReplyWrite,
    ) {
        debug!(
            "[write] start: fh={}, offset={}, size={}",
            fh,
            offset,
            data.len()
        );
        let Some(file_mutex) = self.fhandls.get_file(fh) else {
            reply.error(libc::EBADF);
            return;
        };
        let file = &mut file_mutex.lock().unwrap();

        if let Err(e) = file.seek(std::io::SeekFrom::Start(offset as u64)) {
            reply.error(Error::from(e).0);
            return;
        }
        let mut buf = data;
        while !buf.is_empty() {
            let cnt = match file.write(buf) {
                Ok(cnt) => cnt,
                Err(e) => {
                    reply.error(Error::from(e).0);
                    return;
                }
            };
            buf = &buf[cnt..];
        }
        reply.written(data.len() as u32);
    }

    fn lseek(
        &mut self,
        _req: &Request<'_>,
        _ino: u64,
        fh: u64,
        offset: i64,
        whence: i32,
        reply: fuser::ReplyLseek,
    ) {
        debug!(
            "[lseek] start: fh={}, offset={}, whence={}",
            fh, offset, whence
        );
        let seek_from = match whence {
            libc::SEEK_SET => {
                if offset >= 0 {
                    SeekFrom::Start(offset as u64)
                } else {
                    reply.error(libc::EINVAL);
                    return;
                }
            }
            libc::SEEK_CUR => SeekFrom::Current(offset),
            libc::SEEK_END => SeekFrom::End(offset),
            _ => {
                reply.error(libc::EINVAL);
                return;
            }
        };
        let Some(file_mutex) = self.fhandls.get_file(fh) else {
            reply.error(libc::EBADF);
            return;
        };
        let file = &mut file_mutex.lock().unwrap();
        let pos = match file.seek(seek_from) {
            Ok(p) => p,
            Err(e) => {
                reply.error(Error::from(e).0);
                return;
            }
        };
        reply.offset(pos as i64);
    }

    fn mknod(
        &mut self,
        req: &Request<'_>,
        parent: u64,
        name: &OsStr,
        mode: u32,
        umask: u32,
        _rdev: u32,
        reply: ReplyEntry,
    ) {
        debug!(
            "[mknod] start: parent={}, name={:?}, mode={:o}, umask={:o}",
            parent, name, mode, umask
        );
        if mode & libc::S_IFMT != libc::S_IFREG {
            reply.error(libc::EPERM);
            return;
        }
        let mode = mode & (!umask | libc::S_IFMT);
        let Some(mut new_name) = self.inodes.get_path(parent) else {
            reply.error(libc::ENOENT);
            return;
        };
        new_name.push(name);
        if let Err(e) =
            self.sftp
                .open_mode(&new_name, OpenFlags::CREATE, mode as i32, OpenType::File)
        {
            reply.error(Error::from(e).0);
            return;
        }
        let new_attr = match self.getattr_from_ssh2(&new_name, req.uid(), req.gid()) {
            Ok(a) => a,
            Err(e) => {
                reply.error(e.0);
                return;
            }
        };
        reply.entry(&Duration::from_secs(1), &new_attr, 0);
    }

    fn unlink(&mut self, _req: &Request<'_>, parent: u64, name: &OsStr, reply: fuser::ReplyEmpty) {
        debug!("[unlink] start: parent={}, name={:?}", parent, name);
        let Some(mut path) = self.inodes.get_path(parent) else {
            reply.error(libc::ENOENT);
            return;
        };
        path.push(name);
        match self.sftp.unlink(&path) {
            Ok(_) => {
                self.inodes.del_inode_with_path(&path);
                reply.ok();
            }
            Err(e) => reply.error(Error::from(e).0),
        }
    }

    fn mkdir(
        &mut self,
        req: &Request<'_>,
        parent: u64,
        name: &OsStr,
        mode: u32,
        umask: u32,
        reply: ReplyEntry,
    ) {
        debug!(
            "[mkdir] start: parent={}, name={:?}, mode={:o}, umask={:o}",
            parent, name, mode, umask
        );
        let Some(mut path) = self.inodes.get_path(parent) else {
            reply.error(libc::ENOENT);
            return;
        };
        path.push(name);

        let mode = (mode & (!umask) & 0o777) as i32;

        match self.sftp.mkdir(&path, mode) {
            Ok(_) => match self.getattr_from_ssh2(&path, req.uid(), req.gid()) {
                Ok(attr) => reply.entry(&Duration::from_secs(1), &attr, 0),
                Err(e) => reply.error(e.0),
            },
            Err(e) => reply.error(Error::from(e).0),
        }
    }

    fn rmdir(&mut self, _req: &Request<'_>, parent: u64, name: &OsStr, reply: fuser::ReplyEmpty) {
        debug!("[rmdir] start: parent={}, name={:?}", parent, name);
        let Some(mut path) = self.inodes.get_path(parent) else {
            reply.error(libc::ENOENT);
            return;
        };
        path.push(name);
        match self.sftp.rmdir(&path) {
            Ok(_) => {
                self.inodes.del_inode_with_path(&path);
                reply.ok()
            }
            Err(e) => {
                if e.code() == ErrorCode::Session(-31) {
                    // ssh2ライブラリの返すエラーが妙。置換しておく。
                    reply.error(libc::ENOTEMPTY);
                } else {
                    reply.error(Error::from(e).0)
                }
            }
        }
    }

    fn symlink(
        &mut self,
        req: &Request<'_>,
        parent: u64,
        name: &OsStr,
        link: &Path,
        reply: ReplyEntry,
    ) {
        debug!(
            "[symlink] start: parent={}, name={:?}, link={:?}",
            parent, name, link
        );
        let Some(mut target) = self.inodes.get_path(parent) else {
            reply.error(libc::ENOENT);
            return;
        };
        target.push(name);
        match self.sftp.symlink(link, &target) {
            Ok(_) => match self.getattr_from_ssh2(&target, req.uid(), req.gid()) {
                Ok(attr) => reply.entry(&Duration::from_secs(1), &attr, 0),
                Err(e) => reply.error(e.0),
            },
            Err(e) => reply.error(Error::from(e).0),
        }
    }

    fn setattr(
        &mut self,
        req: &Request<'_>,
        ino: u64,
        mode: Option<u32>,
        _uid: Option<u32>,
        _gid: Option<u32>,
        size: Option<u64>,
        atime: Option<fuser::TimeOrNow>,
        mtime: Option<fuser::TimeOrNow>,
        _ctime: Option<std::time::SystemTime>,
        _fh: Option<u64>,
        _crtime: Option<std::time::SystemTime>,
        _chgtime: Option<std::time::SystemTime>,
        _bkuptime: Option<std::time::SystemTime>,
        _flags: Option<u32>,
        reply: ReplyAttr,
    ) {
        debug!(
            "[setattr] start: ino={}, mode={:?}, size={:?}, atime={:?}, mtime={:?}",
            ino, mode, size, atime, mtime
        );
        let stat = ssh2::FileStat {
            size,
            uid: None,
            gid: None,
            perm: mode,
            atime: atime.map(|t| {
                Self::conv_timeornow2systemtime(&t)
                    .duration_since(UNIX_EPOCH)
                    .unwrap_or_default()
                    .as_secs()
            }),
            mtime: mtime.map(|t| {
                Self::conv_timeornow2systemtime(&t)
                    .duration_since(UNIX_EPOCH)
                    .unwrap_or_default()
                    .as_secs()
            }),
        };
        let Some(filename) = self.inodes.get_path(ino) else {
            reply.error(ENOENT);
            return;
        };
        match self.sftp.setstat(&filename, stat) {
            Ok(_) => {
                let stat = self.getattr_from_ssh2(&filename, req.uid(), req.gid());
                match stat {
                    Ok(s) => reply.attr(&Duration::from_secs(1), &s),
                    Err(e) => reply.error(e.0),
                }
            }
            Err(e) => reply.error(Error::from(e).0),
        }
    }

    fn rename(
        &mut self,
        _req: &Request<'_>,
        parent: u64,
        name: &OsStr,
        newparent: u64,
        newname: &OsStr,
        flags: u32,
        reply: fuser::ReplyEmpty,
    ) {
        debug!(
            "[rename] start: parent={}, name={:?}, newparent={}, newname={:?}, flags={}",
            parent, name, newparent, newname, flags
        );
        let Some(mut old_path) = self.inodes.get_path(parent) else {
            reply.error(libc::ENOENT);
            return;
        };
        old_path.push(name);

        let Some(mut new_path) = self.inodes.get_path(newparent) else {
            reply.error(libc::ENOENT);
            return;
        };
        new_path.push(newname);

        let mut rename_flag = ssh2::RenameFlags::NATIVE;
        if flags & libc::RENAME_EXCHANGE != 0 {
            rename_flag.insert(ssh2::RenameFlags::ATOMIC);
        }
        if flags & libc::RENAME_NOREPLACE == 0 {
            // renameのOVERWRITEが効いてない。手動で消す。
            if let Ok(stat) = self.sftp.lstat(&new_path) {
                if stat.is_dir() {
                    if let Err(e) = self.sftp.rmdir(&new_path) {
                        reply.error(Error::from(e).0);
                        return;
                    }
                } else if let Err(e) = self.sftp.unlink(&new_path) {
                    reply.error(Error::from(e).0);
                    return;
                }
                self.inodes.del_inode_with_path(&new_path);
            }
        }

        match self.sftp.rename(&old_path, &new_path, Some(rename_flag)) {
            Ok(_) => {
                self.inodes.rename(&old_path, &new_path);
                reply.ok();
            }
            Err(e) => reply.error(Error::from(e).0),
        }
    }
}

#[derive(Debug, Clone, Copy)]
struct Error(i32);

impl From<ssh2::Error> for Error {
    fn from(value: ssh2::Error) -> Self {
        let eno = match value.code() {
            ssh2::ErrorCode::Session(_) => libc::ENXIO,
            ssh2::ErrorCode::SFTP(i) => match i {
                // libssh2のlibssh2_sftp.hにて定義されている。
                2 => libc::ENOENT,        // NO_SUCH_FILE
                3 => libc::EACCES,        // permission_denied
                4 => libc::EIO,           // failure
                5 => libc::ENODEV,        // bad message
                6 => libc::ENXIO,         // no connection
                7 => libc::ENETDOWN,      // connection lost
                8 => libc::ENODEV,        // unsported
                9 => libc::EBADF,         // invalid handle
                10 => libc::ENOENT,       //no such path
                11 => libc::EEXIST,       // file already exists
                12 => libc::EACCES,       // write protected
                13 => libc::ENXIO,        // no media
                14 => libc::ENOSPC,       // no space on filesystem
                15 => libc::EDQUOT,       // quota exceeded
                16 => libc::ENODEV,       // unknown principal
                17 => libc::ENOLCK,       // lock conflict
                18 => libc::ENOTEMPTY,    // dir not empty
                19 => libc::ENOTDIR,      // not a directory
                20 => libc::ENAMETOOLONG, // invalid file name
                21 => libc::ELOOP,        // link loop
                _ => {
                    error!("An unknown error occurred during SSH2.[{}]", i);
                    libc::EIO
                }
            },
        };
        Self(eno)
    }
}

impl From<std::io::Error> for Error {
    fn from(value: std::io::Error) -> Self {
        use std::io::ErrorKind::*;
        let eno = match value.kind() {
            NotFound => libc::ENOENT,
            PermissionDenied => libc::EACCES,
            ConnectionRefused => libc::ECONNREFUSED,
            ConnectionReset => libc::ECONNRESET,
            ConnectionAborted => libc::ECONNABORTED,
            NotConnected => libc::ENOTCONN,
            AddrInUse => libc::EADDRINUSE,
            AddrNotAvailable => libc::EADDRNOTAVAIL,
            BrokenPipe => libc::EPIPE,
            AlreadyExists => libc::EEXIST,
            WouldBlock => libc::EWOULDBLOCK,
            InvalidInput => libc::EINVAL,
            InvalidData => libc::EILSEQ,
            TimedOut => libc::ETIMEDOUT,
            WriteZero => libc::EIO,
            Interrupted => libc::EINTR,
            Unsupported => libc::ENOTSUP,
            UnexpectedEof => libc::EOF,
            OutOfMemory => libc::ENOMEM,
            _ => {
                error!(
                    "An unknown error occurred during std::io.[{}]",
                    value.kind()
                );
                libc::EIO
            }
        };
        Self(eno)
    }
}