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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 "qapi/error.h"
23#include "qemu/xattr.h"
24#include "qemu/cutils.h"
25#include "qemu/error-report.h"
26#include "qemu/option.h"
27#include <linux/fs.h>
28#ifdef CONFIG_LINUX_MAGIC_H
29#include <linux/magic.h>
30#endif
31#include <sys/ioctl.h>
32
33#ifndef XFS_SUPER_MAGIC
34#define XFS_SUPER_MAGIC 0x58465342
35#endif
36#ifndef EXT2_SUPER_MAGIC
37#define EXT2_SUPER_MAGIC 0xEF53
38#endif
39#ifndef REISERFS_SUPER_MAGIC
40#define REISERFS_SUPER_MAGIC 0x52654973
41#endif
42#ifndef BTRFS_SUPER_MAGIC
43#define BTRFS_SUPER_MAGIC 0x9123683E
44#endif
45
46typedef struct HandleData {
47 int mountfd;
48 int handle_bytes;
49} HandleData;
50
51static inline int name_to_handle(int dirfd, const char *name,
52 struct file_handle *fh, int *mnt_id, int flags)
53{
54 return name_to_handle_at(dirfd, name, fh, mnt_id, flags);
55}
56
57static inline int open_by_handle(int mountfd, const char *fh, int flags)
58{
59 return open_by_handle_at(mountfd, (struct file_handle *)fh, flags);
60}
61
62static int handle_update_file_cred(int dirfd, const char *name, FsCred *credp)
63{
64 int fd, ret;
65 fd = openat(dirfd, name, O_NONBLOCK | O_NOFOLLOW);
66 if (fd < 0) {
67 return fd;
68 }
69 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
70 if (ret < 0) {
71 goto err_out;
72 }
73 ret = fchmod(fd, credp->fc_mode & 07777);
74err_out:
75 close(fd);
76 return ret;
77}
78
79
80static int handle_lstat(FsContext *fs_ctx, V9fsPath *fs_path,
81 struct stat *stbuf)
82{
83 int fd, ret;
84 HandleData *data = (HandleData *) fs_ctx->private;
85
86 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
87 if (fd < 0) {
88 return fd;
89 }
90 ret = fstatat(fd, "", stbuf, AT_EMPTY_PATH);
91 close(fd);
92 return ret;
93}
94
95static ssize_t handle_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
96 char *buf, size_t bufsz)
97{
98 int fd, ret;
99 HandleData *data = (HandleData *) fs_ctx->private;
100
101 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
102 if (fd < 0) {
103 return fd;
104 }
105 ret = readlinkat(fd, "", buf, bufsz);
106 close(fd);
107 return ret;
108}
109
110static int handle_close(FsContext *ctx, V9fsFidOpenState *fs)
111{
112 return close(fs->fd);
113}
114
115static int handle_closedir(FsContext *ctx, V9fsFidOpenState *fs)
116{
117 return closedir(fs->dir.stream);
118}
119
120static int handle_open(FsContext *ctx, V9fsPath *fs_path,
121 int flags, V9fsFidOpenState *fs)
122{
123 HandleData *data = (HandleData *) ctx->private;
124
125 fs->fd = open_by_handle(data->mountfd, fs_path->data, flags);
126 return fs->fd;
127}
128
129static int handle_opendir(FsContext *ctx,
130 V9fsPath *fs_path, V9fsFidOpenState *fs)
131{
132 int ret;
133 ret = handle_open(ctx, fs_path, O_DIRECTORY, fs);
134 if (ret < 0) {
135 return -1;
136 }
137 fs->dir.stream = fdopendir(ret);
138 if (!fs->dir.stream) {
139 return -1;
140 }
141 return 0;
142}
143
144static void handle_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
145{
146 rewinddir(fs->dir.stream);
147}
148
149static off_t handle_telldir(FsContext *ctx, V9fsFidOpenState *fs)
150{
151 return telldir(fs->dir.stream);
152}
153
154static struct dirent *handle_readdir(FsContext *ctx, V9fsFidOpenState *fs)
155{
156 return readdir(fs->dir.stream);
157}
158
159static void handle_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
160{
161 seekdir(fs->dir.stream, 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 HandleData *data = (HandleData *) 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 HandleData *data = (HandleData *) 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 HandleData *data = (HandleData *) 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.stream);
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 HandleData *data = (HandleData *) 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 HandleData *data = (HandleData *) 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 HandleData *data = (HandleData *) 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 HandleData *data = (HandleData *) 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 HandleData *data = (HandleData *) 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 int fd;
384 HandleData *data = (HandleData *) ctx->private;
385
386 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
387 if (fd < 0) {
388 return fd;
389 }
390 ret = futimens(fd, buf);
391 close(fd);
392 return ret;
393}
394
395static int handle_remove(FsContext *ctx, const char *path)
396{
397 errno = EOPNOTSUPP;
398 return -1;
399}
400
401static int handle_fsync(FsContext *ctx, int fid_type,
402 V9fsFidOpenState *fs, int datasync)
403{
404 int fd;
405
406 if (fid_type == P9_FID_DIR) {
407 fd = dirfd(fs->dir.stream);
408 } else {
409 fd = fs->fd;
410 }
411
412 if (datasync) {
413 return qemu_fdatasync(fd);
414 } else {
415 return fsync(fd);
416 }
417}
418
419static int handle_statfs(FsContext *ctx, V9fsPath *fs_path,
420 struct statfs *stbuf)
421{
422 int fd, ret;
423 HandleData *data = (HandleData *) ctx->private;
424
425 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
426 if (fd < 0) {
427 return fd;
428 }
429 ret = fstatfs(fd, stbuf);
430 close(fd);
431 return ret;
432}
433
434static ssize_t handle_lgetxattr(FsContext *ctx, V9fsPath *fs_path,
435 const char *name, void *value, size_t size)
436{
437 int fd, ret;
438 HandleData *data = (HandleData *) ctx->private;
439
440 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
441 if (fd < 0) {
442 return fd;
443 }
444 ret = fgetxattr(fd, name, value, size);
445 close(fd);
446 return ret;
447}
448
449static ssize_t handle_llistxattr(FsContext *ctx, V9fsPath *fs_path,
450 void *value, size_t size)
451{
452 int fd, ret;
453 HandleData *data = (HandleData *) ctx->private;
454
455 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
456 if (fd < 0) {
457 return fd;
458 }
459 ret = flistxattr(fd, value, size);
460 close(fd);
461 return ret;
462}
463
464static int handle_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name,
465 void *value, size_t size, int flags)
466{
467 int fd, ret;
468 HandleData *data = (HandleData *) ctx->private;
469
470 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
471 if (fd < 0) {
472 return fd;
473 }
474 ret = fsetxattr(fd, name, value, size, flags);
475 close(fd);
476 return ret;
477}
478
479static int handle_lremovexattr(FsContext *ctx, V9fsPath *fs_path,
480 const char *name)
481{
482 int fd, ret;
483 HandleData *data = (HandleData *) ctx->private;
484
485 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
486 if (fd < 0) {
487 return fd;
488 }
489 ret = fremovexattr(fd, name);
490 close(fd);
491 return ret;
492}
493
494static int handle_name_to_path(FsContext *ctx, V9fsPath *dir_path,
495 const char *name, V9fsPath *target)
496{
497 char *buffer;
498 struct file_handle *fh;
499 int dirfd, ret, mnt_id;
500 HandleData *data = (HandleData *) ctx->private;
501
502
503 if (!strcmp(name, ".") || !strcmp(name, "..")) {
504 errno = EINVAL;
505 return -1;
506
507 }
508 if (dir_path) {
509 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
510 } else {
511
512 buffer = rpath(ctx, ".");
513 dirfd = open(buffer, O_DIRECTORY);
514 g_free(buffer);
515 }
516 if (dirfd < 0) {
517 return dirfd;
518 }
519 fh = g_malloc(sizeof(struct file_handle) + data->handle_bytes);
520 fh->handle_bytes = data->handle_bytes;
521
522 buffer = g_strdup_printf("./%s", name);
523
524 ret = name_to_handle(dirfd, buffer, fh, &mnt_id, 0);
525 if (!ret) {
526 target->data = (char *)fh;
527 target->size = sizeof(struct file_handle) + data->handle_bytes;
528 } else {
529 g_free(fh);
530 }
531 close(dirfd);
532 g_free(buffer);
533 return ret;
534}
535
536static int handle_renameat(FsContext *ctx, V9fsPath *olddir,
537 const char *old_name, V9fsPath *newdir,
538 const char *new_name)
539{
540 int olddirfd, newdirfd, ret;
541 HandleData *data = (HandleData *) ctx->private;
542
543 olddirfd = open_by_handle(data->mountfd, olddir->data, O_PATH);
544 if (olddirfd < 0) {
545 return olddirfd;
546 }
547 newdirfd = open_by_handle(data->mountfd, newdir->data, O_PATH);
548 if (newdirfd < 0) {
549 close(olddirfd);
550 return newdirfd;
551 }
552 ret = renameat(olddirfd, old_name, newdirfd, new_name);
553 close(newdirfd);
554 close(olddirfd);
555 return ret;
556}
557
558static int handle_unlinkat(FsContext *ctx, V9fsPath *dir,
559 const char *name, int flags)
560{
561 int dirfd, ret;
562 HandleData *data = (HandleData *) ctx->private;
563
564 dirfd = open_by_handle(data->mountfd, dir->data, O_PATH);
565 if (dirfd < 0) {
566 return dirfd;
567 }
568
569 ret = unlinkat(dirfd, name, flags);
570
571 close(dirfd);
572 return ret;
573}
574
575static int handle_ioc_getversion(FsContext *ctx, V9fsPath *path,
576 mode_t st_mode, uint64_t *st_gen)
577{
578#ifdef FS_IOC_GETVERSION
579 int err;
580 V9fsFidOpenState fid_open;
581
582
583
584
585
586 if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
587 errno = ENOTTY;
588 return -1;
589 }
590 err = handle_open(ctx, path, O_RDONLY, &fid_open);
591 if (err < 0) {
592 return err;
593 }
594 err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen);
595 handle_close(ctx, &fid_open);
596 return err;
597#else
598 errno = ENOTTY;
599 return -1;
600#endif
601}
602
603static int handle_init(FsContext *ctx, Error **errp)
604{
605 int ret, mnt_id;
606 struct statfs stbuf;
607 struct file_handle fh;
608 HandleData *data = g_malloc(sizeof(HandleData));
609
610 data->mountfd = open(ctx->fs_root, O_DIRECTORY);
611 if (data->mountfd < 0) {
612 ret = data->mountfd;
613 goto err_out;
614 }
615 ret = statfs(ctx->fs_root, &stbuf);
616 if (!ret) {
617 switch (stbuf.f_type) {
618 case EXT2_SUPER_MAGIC:
619 case BTRFS_SUPER_MAGIC:
620 case REISERFS_SUPER_MAGIC:
621 case XFS_SUPER_MAGIC:
622 ctx->exops.get_st_gen = handle_ioc_getversion;
623 break;
624 }
625 }
626 memset(&fh, 0, sizeof(struct file_handle));
627 ret = name_to_handle(data->mountfd, ".", &fh, &mnt_id, 0);
628 if (ret && errno == EOVERFLOW) {
629 data->handle_bytes = fh.handle_bytes;
630 ctx->private = data;
631 ret = 0;
632 goto out;
633 }
634
635 ret = -1;
636 close(data->mountfd);
637err_out:
638 g_free(data);
639out:
640 return ret;
641}
642
643static void handle_cleanup(FsContext *ctx)
644{
645 HandleData *data = ctx->private;
646
647 close(data->mountfd);
648 g_free(data);
649}
650
651static int handle_parse_opts(QemuOpts *opts, FsDriverEntry *fse, Error **errp)
652{
653 const char *sec_model = qemu_opt_get(opts, "security_model");
654 const char *path = qemu_opt_get(opts, "path");
655
656 warn_report("handle backend is deprecated");
657
658 if (sec_model) {
659 error_setg(errp,
660 "Invalid argument security_model specified with handle fsdriver");
661 return -1;
662 }
663
664 if (!path) {
665 error_setg(errp, "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 .cleanup = handle_cleanup,
677 .lstat = handle_lstat,
678 .readlink = handle_readlink,
679 .close = handle_close,
680 .closedir = handle_closedir,
681 .open = handle_open,
682 .opendir = handle_opendir,
683 .rewinddir = handle_rewinddir,
684 .telldir = handle_telldir,
685 .readdir = handle_readdir,
686 .seekdir = handle_seekdir,
687 .preadv = handle_preadv,
688 .pwritev = handle_pwritev,
689 .chmod = handle_chmod,
690 .mknod = handle_mknod,
691 .mkdir = handle_mkdir,
692 .fstat = handle_fstat,
693 .open2 = handle_open2,
694 .symlink = handle_symlink,
695 .link = handle_link,
696 .truncate = handle_truncate,
697 .rename = handle_rename,
698 .chown = handle_chown,
699 .utimensat = handle_utimensat,
700 .remove = handle_remove,
701 .fsync = handle_fsync,
702 .statfs = handle_statfs,
703 .lgetxattr = handle_lgetxattr,
704 .llistxattr = handle_llistxattr,
705 .lsetxattr = handle_lsetxattr,
706 .lremovexattr = handle_lremovexattr,
707 .name_to_path = handle_name_to_path,
708 .renameat = handle_renameat,
709 .unlinkat = handle_unlinkat,
710};
711
