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14#include "qemu/osdep.h"
15#include "9p.h"
16#include "9p-xattr.h"
17#include <arpa/inet.h>
18#include <pwd.h>
19#include <grp.h>
20#include <sys/socket.h>
21#include <sys/un.h>
22#include "qemu/xattr.h"
23#include "qemu/cutils.h"
24#include "qemu/error-report.h"
25#include <linux/fs.h>
26#ifdef CONFIG_LINUX_MAGIC_H
27#include <linux/magic.h>
28#endif
29#include <sys/ioctl.h>
30
31#ifndef XFS_SUPER_MAGIC
32#define XFS_SUPER_MAGIC 0x58465342
33#endif
34#ifndef EXT2_SUPER_MAGIC
35#define EXT2_SUPER_MAGIC 0xEF53
36#endif
37#ifndef REISERFS_SUPER_MAGIC
38#define REISERFS_SUPER_MAGIC 0x52654973
39#endif
40#ifndef BTRFS_SUPER_MAGIC
41#define BTRFS_SUPER_MAGIC 0x9123683E
42#endif
43
44struct handle_data {
45 int mountfd;
46 int handle_bytes;
47};
48
49static inline int name_to_handle(int dirfd, const char *name,
50 struct file_handle *fh, int *mnt_id, int flags)
51{
52 return name_to_handle_at(dirfd, name, fh, mnt_id, flags);
53}
54
55static inline int open_by_handle(int mountfd, const char *fh, int flags)
56{
57 return open_by_handle_at(mountfd, (struct file_handle *)fh, flags);
58}
59
60static int handle_update_file_cred(int dirfd, const char *name, FsCred *credp)
61{
62 int fd, ret;
63 fd = openat(dirfd, name, O_NONBLOCK | O_NOFOLLOW);
64 if (fd < 0) {
65 return fd;
66 }
67 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
68 if (ret < 0) {
69 goto err_out;
70 }
71 ret = fchmod(fd, credp->fc_mode & 07777);
72err_out:
73 close(fd);
74 return ret;
75}
76
77
78static int handle_lstat(FsContext *fs_ctx, V9fsPath *fs_path,
79 struct stat *stbuf)
80{
81 int fd, ret;
82 struct handle_data *data = (struct handle_data *)fs_ctx->private;
83
84 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
85 if (fd < 0) {
86 return fd;
87 }
88 ret = fstatat(fd, "", stbuf, AT_EMPTY_PATH);
89 close(fd);
90 return ret;
91}
92
93static ssize_t handle_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
94 char *buf, size_t bufsz)
95{
96 int fd, ret;
97 struct handle_data *data = (struct handle_data *)fs_ctx->private;
98
99 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
100 if (fd < 0) {
101 return fd;
102 }
103 ret = readlinkat(fd, "", buf, bufsz);
104 close(fd);
105 return ret;
106}
107
108static int handle_close(FsContext *ctx, V9fsFidOpenState *fs)
109{
110 return close(fs->fd);
111}
112
113static int handle_closedir(FsContext *ctx, V9fsFidOpenState *fs)
114{
115 return closedir(fs->dir);
116}
117
118static int handle_open(FsContext *ctx, V9fsPath *fs_path,
119 int flags, V9fsFidOpenState *fs)
120{
121 struct handle_data *data = (struct handle_data *)ctx->private;
122
123 fs->fd = open_by_handle(data->mountfd, fs_path->data, flags);
124 return fs->fd;
125}
126
127static int handle_opendir(FsContext *ctx,
128 V9fsPath *fs_path, V9fsFidOpenState *fs)
129{
130 int ret;
131 ret = handle_open(ctx, fs_path, O_DIRECTORY, fs);
132 if (ret < 0) {
133 return -1;
134 }
135 fs->dir = fdopendir(ret);
136 if (!fs->dir) {
137 return -1;
138 }
139 return 0;
140}
141
142static void handle_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
143{
144 rewinddir(fs->dir);
145}
146
147static off_t handle_telldir(FsContext *ctx, V9fsFidOpenState *fs)
148{
149 return telldir(fs->dir);
150}
151
152static int handle_readdir_r(FsContext *ctx, V9fsFidOpenState *fs,
153 struct dirent *entry,
154 struct dirent **result)
155{
156 return readdir_r(fs->dir, entry, result);
157}
158
159static void handle_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
160{
161 seekdir(fs->dir, off);
162}
163
164static ssize_t handle_preadv(FsContext *ctx, V9fsFidOpenState *fs,
165 const struct iovec *iov,
166 int iovcnt, off_t offset)
167{
168#ifdef CONFIG_PREADV
169 return preadv(fs->fd, iov, iovcnt, offset);
170#else
171 int err = lseek(fs->fd, offset, SEEK_SET);
172 if (err == -1) {
173 return err;
174 } else {
175 return readv(fs->fd, iov, iovcnt);
176 }
177#endif
178}
179
180static ssize_t handle_pwritev(FsContext *ctx, V9fsFidOpenState *fs,
181 const struct iovec *iov,
182 int iovcnt, off_t offset)
183{
184 ssize_t ret;
185#ifdef CONFIG_PREADV
186 ret = pwritev(fs->fd, iov, iovcnt, offset);
187#else
188 int err = lseek(fs->fd, offset, SEEK_SET);
189 if (err == -1) {
190 return err;
191 } else {
192 ret = writev(fs->fd, iov, iovcnt);
193 }
194#endif
195#ifdef CONFIG_SYNC_FILE_RANGE
196 if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) {
197
198
199
200
201
202 sync_file_range(fs->fd, offset, ret,
203 SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE);
204 }
205#endif
206 return ret;
207}
208
209static int handle_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
210{
211 int fd, ret;
212 struct handle_data *data = (struct handle_data *)fs_ctx->private;
213
214 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
215 if (fd < 0) {
216 return fd;
217 }
218 ret = fchmod(fd, credp->fc_mode);
219 close(fd);
220 return ret;
221}
222
223static int handle_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
224 const char *name, FsCred *credp)
225{
226 int dirfd, ret;
227 struct handle_data *data = (struct handle_data *)fs_ctx->private;
228
229 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
230 if (dirfd < 0) {
231 return dirfd;
232 }
233 ret = mknodat(dirfd, name, credp->fc_mode, credp->fc_rdev);
234 if (!ret) {
235 ret = handle_update_file_cred(dirfd, name, credp);
236 }
237 close(dirfd);
238 return ret;
239}
240
241static int handle_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
242 const char *name, FsCred *credp)
243{
244 int dirfd, ret;
245 struct handle_data *data = (struct handle_data *)fs_ctx->private;
246
247 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
248 if (dirfd < 0) {
249 return dirfd;
250 }
251 ret = mkdirat(dirfd, name, credp->fc_mode);
252 if (!ret) {
253 ret = handle_update_file_cred(dirfd, name, credp);
254 }
255 close(dirfd);
256 return ret;
257}
258
259static int handle_fstat(FsContext *fs_ctx, int fid_type,
260 V9fsFidOpenState *fs, struct stat *stbuf)
261{
262 int fd;
263
264 if (fid_type == P9_FID_DIR) {
265 fd = dirfd(fs->dir);
266 } else {
267 fd = fs->fd;
268 }
269 return fstat(fd, stbuf);
270}
271
272static int handle_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name,
273 int flags, FsCred *credp, V9fsFidOpenState *fs)
274{
275 int ret;
276 int dirfd, fd;
277 struct handle_data *data = (struct handle_data *)fs_ctx->private;
278
279 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
280 if (dirfd < 0) {
281 return dirfd;
282 }
283 fd = openat(dirfd, name, flags | O_NOFOLLOW, credp->fc_mode);
284 if (fd >= 0) {
285 ret = handle_update_file_cred(dirfd, name, credp);
286 if (ret < 0) {
287 close(fd);
288 fd = ret;
289 } else {
290 fs->fd = fd;
291 }
292 }
293 close(dirfd);
294 return fd;
295}
296
297
298static int handle_symlink(FsContext *fs_ctx, const char *oldpath,
299 V9fsPath *dir_path, const char *name, FsCred *credp)
300{
301 int fd, dirfd, ret;
302 struct handle_data *data = (struct handle_data *)fs_ctx->private;
303
304 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
305 if (dirfd < 0) {
306 return dirfd;
307 }
308 ret = symlinkat(oldpath, dirfd, name);
309 if (!ret) {
310 fd = openat(dirfd, name, O_PATH | O_NOFOLLOW);
311 if (fd < 0) {
312 ret = fd;
313 goto err_out;
314 }
315 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
316 close(fd);
317 }
318err_out:
319 close(dirfd);
320 return ret;
321}
322
323static int handle_link(FsContext *ctx, V9fsPath *oldpath,
324 V9fsPath *dirpath, const char *name)
325{
326 int oldfd, newdirfd, ret;
327 struct handle_data *data = (struct handle_data *)ctx->private;
328
329 oldfd = open_by_handle(data->mountfd, oldpath->data, O_PATH);
330 if (oldfd < 0) {
331 return oldfd;
332 }
333 newdirfd = open_by_handle(data->mountfd, dirpath->data, O_PATH);
334 if (newdirfd < 0) {
335 close(oldfd);
336 return newdirfd;
337 }
338 ret = linkat(oldfd, "", newdirfd, name, AT_EMPTY_PATH);
339 close(newdirfd);
340 close(oldfd);
341 return ret;
342}
343
344static int handle_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size)
345{
346 int fd, ret;
347 struct handle_data *data = (struct handle_data *)ctx->private;
348
349 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK | O_WRONLY);
350 if (fd < 0) {
351 return fd;
352 }
353 ret = ftruncate(fd, size);
354 close(fd);
355 return ret;
356}
357
358static int handle_rename(FsContext *ctx, const char *oldpath,
359 const char *newpath)
360{
361 errno = EOPNOTSUPP;
362 return -1;
363}
364
365static int handle_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
366{
367 int fd, ret;
368 struct handle_data *data = (struct handle_data *)fs_ctx->private;
369
370 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
371 if (fd < 0) {
372 return fd;
373 }
374 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
375 close(fd);
376 return ret;
377}
378
379static int handle_utimensat(FsContext *ctx, V9fsPath *fs_path,
380 const struct timespec *buf)
381{
382 int ret;
383#ifdef CONFIG_UTIMENSAT
384 int fd;
385 struct handle_data *data = (struct handle_data *)ctx->private;
386
387 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
388 if (fd < 0) {
389 return fd;
390 }
391 ret = futimens(fd, buf);
392 close(fd);
393#else
394 ret = -1;
395 errno = ENOSYS;
396#endif
397 return ret;
398}
399
400static int handle_remove(FsContext *ctx, const char *path)
401{
402 errno = EOPNOTSUPP;
403 return -1;
404}
405
406static int handle_fsync(FsContext *ctx, int fid_type,
407 V9fsFidOpenState *fs, int datasync)
408{
409 int fd;
410
411 if (fid_type == P9_FID_DIR) {
412 fd = dirfd(fs->dir);
413 } else {
414 fd = fs->fd;
415 }
416
417 if (datasync) {
418 return qemu_fdatasync(fd);
419 } else {
420 return fsync(fd);
421 }
422}
423
424static int handle_statfs(FsContext *ctx, V9fsPath *fs_path,
425 struct statfs *stbuf)
426{
427 int fd, ret;
428 struct handle_data *data = (struct handle_data *)ctx->private;
429
430 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
431 if (fd < 0) {
432 return fd;
433 }
434 ret = fstatfs(fd, stbuf);
435 close(fd);
436 return ret;
437}
438
439static ssize_t handle_lgetxattr(FsContext *ctx, V9fsPath *fs_path,
440 const char *name, void *value, size_t size)
441{
442 int fd, ret;
443 struct handle_data *data = (struct handle_data *)ctx->private;
444
445 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
446 if (fd < 0) {
447 return fd;
448 }
449 ret = fgetxattr(fd, name, value, size);
450 close(fd);
451 return ret;
452}
453
454static ssize_t handle_llistxattr(FsContext *ctx, V9fsPath *fs_path,
455 void *value, size_t size)
456{
457 int fd, ret;
458 struct handle_data *data = (struct handle_data *)ctx->private;
459
460 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
461 if (fd < 0) {
462 return fd;
463 }
464 ret = flistxattr(fd, value, size);
465 close(fd);
466 return ret;
467}
468
469static int handle_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name,
470 void *value, size_t size, int flags)
471{
472 int fd, ret;
473 struct handle_data *data = (struct handle_data *)ctx->private;
474
475 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
476 if (fd < 0) {
477 return fd;
478 }
479 ret = fsetxattr(fd, name, value, size, flags);
480 close(fd);
481 return ret;
482}
483
484static int handle_lremovexattr(FsContext *ctx, V9fsPath *fs_path,
485 const char *name)
486{
487 int fd, ret;
488 struct handle_data *data = (struct handle_data *)ctx->private;
489
490 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
491 if (fd < 0) {
492 return fd;
493 }
494 ret = fremovexattr(fd, name);
495 close(fd);
496 return ret;
497}
498
499static int handle_name_to_path(FsContext *ctx, V9fsPath *dir_path,
500 const char *name, V9fsPath *target)
501{
502 char *buffer;
503 struct file_handle *fh;
504 int dirfd, ret, mnt_id;
505 struct handle_data *data = (struct handle_data *)ctx->private;
506
507
508 if (!strcmp(name, ".") || !strcmp(name, "..")) {
509 errno = EINVAL;
510 return -1;
511
512 }
513 if (dir_path) {
514 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
515 } else {
516
517 buffer = rpath(ctx, ".");
518 dirfd = open(buffer, O_DIRECTORY);
519 g_free(buffer);
520 }
521 if (dirfd < 0) {
522 return dirfd;
523 }
524 fh = g_malloc(sizeof(struct file_handle) + data->handle_bytes);
525 fh->handle_bytes = data->handle_bytes;
526
527 buffer = g_strdup_printf("./%s", name);
528
529 ret = name_to_handle(dirfd, buffer, fh, &mnt_id, 0);
530 if (!ret) {
531 target->data = (char *)fh;
532 target->size = sizeof(struct file_handle) + data->handle_bytes;
533 } else {
534 g_free(fh);
535 }
536 close(dirfd);
537 g_free(buffer);
538 return ret;
539}
540
541static int handle_renameat(FsContext *ctx, V9fsPath *olddir,
542 const char *old_name, V9fsPath *newdir,
543 const char *new_name)
544{
545 int olddirfd, newdirfd, ret;
546 struct handle_data *data = (struct handle_data *)ctx->private;
547
548 olddirfd = open_by_handle(data->mountfd, olddir->data, O_PATH);
549 if (olddirfd < 0) {
550 return olddirfd;
551 }
552 newdirfd = open_by_handle(data->mountfd, newdir->data, O_PATH);
553 if (newdirfd < 0) {
554 close(olddirfd);
555 return newdirfd;
556 }
557 ret = renameat(olddirfd, old_name, newdirfd, new_name);
558 close(newdirfd);
559 close(olddirfd);
560 return ret;
561}
562
563static int handle_unlinkat(FsContext *ctx, V9fsPath *dir,
564 const char *name, int flags)
565{
566 int dirfd, ret;
567 struct handle_data *data = (struct handle_data *)ctx->private;
568 int rflags;
569
570 dirfd = open_by_handle(data->mountfd, dir->data, O_PATH);
571 if (dirfd < 0) {
572 return dirfd;
573 }
574
575 rflags = 0;
576 if (flags & P9_DOTL_AT_REMOVEDIR) {
577 rflags |= AT_REMOVEDIR;
578 }
579
580 ret = unlinkat(dirfd, name, rflags);
581
582 close(dirfd);
583 return ret;
584}
585
586static int handle_ioc_getversion(FsContext *ctx, V9fsPath *path,
587 mode_t st_mode, uint64_t *st_gen)
588{
589#ifdef FS_IOC_GETVERSION
590 int err;
591 V9fsFidOpenState fid_open;
592
593
594
595
596
597 if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
598 errno = ENOTTY;
599 return -1;
600 }
601 err = handle_open(ctx, path, O_RDONLY, &fid_open);
602 if (err < 0) {
603 return err;
604 }
605 err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen);
606 handle_close(ctx, &fid_open);
607 return err;
608#else
609 errno = ENOTTY;
610 return -1;
611#endif
612}
613
614static int handle_init(FsContext *ctx)
615{
616 int ret, mnt_id;
617 struct statfs stbuf;
618 struct file_handle fh;
619 struct handle_data *data = g_malloc(sizeof(struct handle_data));
620
621 data->mountfd = open(ctx->fs_root, O_DIRECTORY);
622 if (data->mountfd < 0) {
623 ret = data->mountfd;
624 goto err_out;
625 }
626 ret = statfs(ctx->fs_root, &stbuf);
627 if (!ret) {
628 switch (stbuf.f_type) {
629 case EXT2_SUPER_MAGIC:
630 case BTRFS_SUPER_MAGIC:
631 case REISERFS_SUPER_MAGIC:
632 case XFS_SUPER_MAGIC:
633 ctx->exops.get_st_gen = handle_ioc_getversion;
634 break;
635 }
636 }
637 memset(&fh, 0, sizeof(struct file_handle));
638 ret = name_to_handle(data->mountfd, ".", &fh, &mnt_id, 0);
639 if (ret && errno == EOVERFLOW) {
640 data->handle_bytes = fh.handle_bytes;
641 ctx->private = data;
642 ret = 0;
643 goto out;
644 }
645
646 ret = -1;
647 close(data->mountfd);
648err_out:
649 g_free(data);
650out:
651 return ret;
652}
653
654static int handle_parse_opts(QemuOpts *opts, struct FsDriverEntry *fse)
655{
656 const char *sec_model = qemu_opt_get(opts, "security_model");
657 const char *path = qemu_opt_get(opts, "path");
658
659 if (sec_model) {
660 error_report("Invalid argument security_model specified with handle fsdriver");
661 return -1;
662 }
663
664 if (!path) {
665 error_report("fsdev: No path specified");
666 return -1;
667 }
668 fse->path = g_strdup(path);
669 return 0;
670
671}
672
673FileOperations handle_ops = {
674 .parse_opts = handle_parse_opts,
675 .init = handle_init,
676 .lstat = handle_lstat,
677 .readlink = handle_readlink,
678 .close = handle_close,
679 .closedir = handle_closedir,
680 .open = handle_open,
681 .opendir = handle_opendir,
682 .rewinddir = handle_rewinddir,
683 .telldir = handle_telldir,
684 .readdir_r = handle_readdir_r,
685 .seekdir = handle_seekdir,
686 .preadv = handle_preadv,
687 .pwritev = handle_pwritev,
688 .chmod = handle_chmod,
689 .mknod = handle_mknod,
690 .mkdir = handle_mkdir,
691 .fstat = handle_fstat,
692 .open2 = handle_open2,
693 .symlink = handle_symlink,
694 .link = handle_link,
695 .truncate = handle_truncate,
696 .rename = handle_rename,
697 .chown = handle_chown,
698 .utimensat = handle_utimensat,
699 .remove = handle_remove,
700 .fsync = handle_fsync,
701 .statfs = handle_statfs,
702 .lgetxattr = handle_lgetxattr,
703 .llistxattr = handle_llistxattr,
704 .lsetxattr = handle_lsetxattr,
705 .lremovexattr = handle_lremovexattr,
706 .name_to_path = handle_name_to_path,
707 .renameat = handle_renameat,
708 .unlinkat = handle_unlinkat,
709};
710
