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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <stdio.h>
7#include <unistd.h>
8#include <stdlib.h>
9#include <string.h>
10#include <errno.h>
11#include <fcntl.h>
12#include <signal.h>
13#include <linux/falloc.h>
14#include <sys/ioctl.h>
15#include <sys/mount.h>
16#include <sys/socket.h>
17#include <sys/stat.h>
18#include <sys/sysmacros.h>
19#include <sys/un.h>
20#include <sys/mman.h>
21#include <sys/types.h>
22#include <sys/eventfd.h>
23#include <poll.h>
24#include <os.h>
25
26static void copy_stat(struct uml_stat *dst, const struct stat64 *src)
27{
28 *dst = ((struct uml_stat) {
29 .ust_dev = src->st_dev, /* device */
30 .ust_ino = src->st_ino, /* inode */
31 .ust_mode = src->st_mode, /* protection */
32 .ust_nlink = src->st_nlink, /* number of hard links */
33 .ust_uid = src->st_uid, /* user ID of owner */
34 .ust_gid = src->st_gid, /* group ID of owner */
35 .ust_size = src->st_size, /* total size, in bytes */
36 .ust_blksize = src->st_blksize, /* blocksize for filesys I/O */
37 .ust_blocks = src->st_blocks, /* number of blocks allocated */
38 .ust_atime = src->st_atime, /* time of last access */
39 .ust_mtime = src->st_mtime, /* time of last modification */
40 .ust_ctime = src->st_ctime, /* time of last change */
41 });
42}
43
44int os_stat_fd(const int fd, struct uml_stat *ubuf)
45{
46 struct stat64 sbuf;
47 int err;
48
49 CATCH_EINTR(err = fstat64(fd, &sbuf));
50 if (err < 0)
51 return -errno;
52
53 if (ubuf != NULL)
54 copy_stat(ubuf, &sbuf);
55 return err;
56}
57
58int os_stat_file(const char *file_name, struct uml_stat *ubuf)
59{
60 struct stat64 sbuf;
61 int err;
62
63 CATCH_EINTR(err = stat64(file_name, &sbuf));
64 if (err < 0)
65 return -errno;
66
67 if (ubuf != NULL)
68 copy_stat(ubuf, &sbuf);
69 return err;
70}
71
72int os_access(const char *file, int mode)
73{
74 int amode, err;
75
76 amode = (mode & OS_ACC_R_OK ? R_OK : 0) |
77 (mode & OS_ACC_W_OK ? W_OK : 0) |
78 (mode & OS_ACC_X_OK ? X_OK : 0) |
79 (mode & OS_ACC_F_OK ? F_OK : 0);
80
81 err = access(file, amode);
82 if (err < 0)
83 return -errno;
84
85 return 0;
86}
87
88/* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
89int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
90{
91 int err;
92
93 err = ioctl(fd, cmd, arg);
94 if (err < 0)
95 return -errno;
96
97 return err;
98}
99
100/* FIXME: ensure namebuf in os_get_if_name is big enough */
101int os_get_ifname(int fd, char* namebuf)
102{
103 if (ioctl(fd, SIOCGIFNAME, namebuf) < 0)
104 return -errno;
105
106 return 0;
107}
108
109int os_mode_fd(int fd, int mode)
110{
111 int err;
112
113 CATCH_EINTR(err = fchmod(fd, mode));
114 if (err < 0)
115 return -errno;
116
117 return 0;
118}
119
120int os_file_type(char *file)
121{
122 struct uml_stat buf;
123 int err;
124
125 err = os_stat_file(file, &buf);
126 if (err < 0)
127 return err;
128
129 if (S_ISDIR(buf.ust_mode))
130 return OS_TYPE_DIR;
131 else if (S_ISLNK(buf.ust_mode))
132 return OS_TYPE_SYMLINK;
133 else if (S_ISCHR(buf.ust_mode))
134 return OS_TYPE_CHARDEV;
135 else if (S_ISBLK(buf.ust_mode))
136 return OS_TYPE_BLOCKDEV;
137 else if (S_ISFIFO(buf.ust_mode))
138 return OS_TYPE_FIFO;
139 else if (S_ISSOCK(buf.ust_mode))
140 return OS_TYPE_SOCK;
141 else return OS_TYPE_FILE;
142}
143
144int os_file_mode(const char *file, struct openflags *mode_out)
145{
146 int err;
147
148 *mode_out = OPENFLAGS();
149
150 err = access(file, W_OK);
151 if (err && (errno != EACCES))
152 return -errno;
153 else if (!err)
154 *mode_out = of_write(*mode_out);
155
156 err = access(file, R_OK);
157 if (err && (errno != EACCES))
158 return -errno;
159 else if (!err)
160 *mode_out = of_read(*mode_out);
161
162 return err;
163}
164
165int os_open_file(const char *file, struct openflags flags, int mode)
166{
167 int fd, err, f = 0;
168
169 if (flags.r && flags.w)
170 f = O_RDWR;
171 else if (flags.r)
172 f = O_RDONLY;
173 else if (flags.w)
174 f = O_WRONLY;
175 else f = 0;
176
177 if (flags.s)
178 f |= O_SYNC;
179 if (flags.c)
180 f |= O_CREAT;
181 if (flags.t)
182 f |= O_TRUNC;
183 if (flags.e)
184 f |= O_EXCL;
185 if (flags.a)
186 f |= O_APPEND;
187
188 fd = open64(file, f, mode);
189 if (fd < 0)
190 return -errno;
191
192 if (flags.cl && fcntl(fd, F_SETFD, 1)) {
193 err = -errno;
194 close(fd);
195 return err;
196 }
197
198 return fd;
199}
200
201int os_connect_socket(const char *name)
202{
203 struct sockaddr_un sock;
204 int fd, err;
205
206 sock.sun_family = AF_UNIX;
207 snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
208
209 fd = socket(AF_UNIX, SOCK_STREAM, 0);
210 if (fd < 0) {
211 err = -errno;
212 goto out;
213 }
214
215 err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
216 if (err) {
217 err = -errno;
218 goto out_close;
219 }
220
221 return fd;
222
223out_close:
224 close(fd);
225out:
226 return err;
227}
228
229int os_dup_file(int fd)
230{
231 int new_fd = dup(fd);
232
233 if (new_fd < 0)
234 return -errno;
235
236 return new_fd;
237}
238
239void os_close_file(int fd)
240{
241 close(fd);
242}
243
244int os_seek_file(int fd, unsigned long long offset)
245{
246 unsigned long long actual;
247
248 actual = lseek64(fd, offset, SEEK_SET);
249 if (actual != offset)
250 return -errno;
251 return 0;
252}
253
254int os_read_file(int fd, void *buf, int len)
255{
256 int n = read(fd, buf, len);
257
258 if (n < 0)
259 return -errno;
260 return n;
261}
262
263int os_pread_file(int fd, void *buf, int len, unsigned long long offset)
264{
265 int n = pread(fd, buf, len, offset);
266
267 if (n < 0)
268 return -errno;
269 return n;
270}
271
272int os_write_file(int fd, const void *buf, int len)
273{
274 int n = write(fd, (void *) buf, len);
275
276 if (n < 0)
277 return -errno;
278 return n;
279}
280
281int os_sync_file(int fd)
282{
283 int n = fdatasync(fd);
284
285 if (n < 0)
286 return -errno;
287 return n;
288}
289
290int os_pwrite_file(int fd, const void *buf, int len, unsigned long long offset)
291{
292 int n = pwrite(fd, (void *) buf, len, offset);
293
294 if (n < 0)
295 return -errno;
296 return n;
297}
298
299
300int os_file_size(const char *file, unsigned long long *size_out)
301{
302 struct uml_stat buf;
303 int err;
304
305 err = os_stat_file(file, &buf);
306 if (err < 0) {
307 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
308 -err);
309 return err;
310 }
311
312 if (S_ISBLK(buf.ust_mode)) {
313 int fd;
314 long blocks;
315
316 fd = open(file, O_RDONLY, 0);
317 if (fd < 0) {
318 err = -errno;
319 printk(UM_KERN_ERR "Couldn't open \"%s\", "
320 "errno = %d\n", file, errno);
321 return err;
322 }
323 if (ioctl(fd, BLKGETSIZE, &blocks) < 0) {
324 err = -errno;
325 printk(UM_KERN_ERR "Couldn't get the block size of "
326 "\"%s\", errno = %d\n", file, errno);
327 close(fd);
328 return err;
329 }
330 *size_out = ((long long) blocks) * 512;
331 close(fd);
332 }
333 else *size_out = buf.ust_size;
334
335 return 0;
336}
337
338int os_file_modtime(const char *file, long long *modtime)
339{
340 struct uml_stat buf;
341 int err;
342
343 err = os_stat_file(file, &buf);
344 if (err < 0) {
345 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
346 -err);
347 return err;
348 }
349
350 *modtime = buf.ust_mtime;
351 return 0;
352}
353
354int os_set_exec_close(int fd)
355{
356 int err;
357
358 CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC));
359
360 if (err < 0)
361 return -errno;
362 return err;
363}
364
365int os_pipe(int *fds, int stream, int close_on_exec)
366{
367 int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
368
369 err = socketpair(AF_UNIX, type, 0, fds);
370 if (err < 0)
371 return -errno;
372
373 if (!close_on_exec)
374 return 0;
375
376 err = os_set_exec_close(fds[0]);
377 if (err < 0)
378 goto error;
379
380 err = os_set_exec_close(fds[1]);
381 if (err < 0)
382 goto error;
383
384 return 0;
385
386 error:
387 printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n",
388 -err);
389 close(fds[1]);
390 close(fds[0]);
391 return err;
392}
393
394int os_set_fd_async(int fd)
395{
396 int err, flags;
397
398 flags = fcntl(fd, F_GETFL);
399 if (flags < 0)
400 return -errno;
401
402 flags |= O_ASYNC | O_NONBLOCK;
403 if (fcntl(fd, F_SETFL, flags) < 0) {
404 err = -errno;
405 printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC "
406 "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
407 return err;
408 }
409
410 if ((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
411 (fcntl(fd, F_SETOWN, os_getpid()) < 0)) {
412 err = -errno;
413 printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN "
414 "(or F_SETSIG) fd %d, errno = %d\n", fd, errno);
415 return err;
416 }
417
418 return 0;
419}
420
421int os_clear_fd_async(int fd)
422{
423 int flags;
424
425 flags = fcntl(fd, F_GETFL);
426 if (flags < 0)
427 return -errno;
428
429 flags &= ~(O_ASYNC | O_NONBLOCK);
430 if (fcntl(fd, F_SETFL, flags) < 0)
431 return -errno;
432 return 0;
433}
434
435int os_set_fd_block(int fd, int blocking)
436{
437 int flags;
438
439 flags = fcntl(fd, F_GETFL);
440 if (flags < 0)
441 return -errno;
442
443 if (blocking)
444 flags &= ~O_NONBLOCK;
445 else
446 flags |= O_NONBLOCK;
447
448 if (fcntl(fd, F_SETFL, flags) < 0)
449 return -errno;
450
451 return 0;
452}
453
454int os_accept_connection(int fd)
455{
456 int new;
457
458 new = accept(fd, NULL, 0);
459 if (new < 0)
460 return -errno;
461 return new;
462}
463
464#ifndef SHUT_RD
465#define SHUT_RD 0
466#endif
467
468#ifndef SHUT_WR
469#define SHUT_WR 1
470#endif
471
472#ifndef SHUT_RDWR
473#define SHUT_RDWR 2
474#endif
475
476int os_shutdown_socket(int fd, int r, int w)
477{
478 int what, err;
479
480 if (r && w)
481 what = SHUT_RDWR;
482 else if (r)
483 what = SHUT_RD;
484 else if (w)
485 what = SHUT_WR;
486 else
487 return -EINVAL;
488
489 err = shutdown(fd, what);
490 if (err < 0)
491 return -errno;
492 return 0;
493}
494
495/**
496 * os_rcv_fd_msg - receive message with (optional) FDs
497 * @fd: the FD to receive from
498 * @fds: the array for FDs to write to
499 * @n_fds: number of FDs to receive (@fds array size)
500 * @data: the message buffer
501 * @data_len: the size of the message to receive
502 *
503 * Receive a message with FDs.
504 *
505 * Returns: the size of the received message, or an error code
506 */
507ssize_t os_rcv_fd_msg(int fd, int *fds, unsigned int n_fds,
508 void *data, size_t data_len)
509{
510#define MAX_RCV_FDS 2
511 char buf[CMSG_SPACE(sizeof(*fds) * MAX_RCV_FDS)];
512 struct cmsghdr *cmsg;
513 struct iovec iov = {
514 .iov_base = data,
515 .iov_len = data_len,
516 };
517 struct msghdr msg = {
518 .msg_iov = &iov,
519 .msg_iovlen = 1,
520 .msg_control = buf,
521 .msg_controllen = CMSG_SPACE(sizeof(*fds) * n_fds),
522 };
523 int n;
524
525 if (n_fds > MAX_RCV_FDS)
526 return -EINVAL;
527
528 n = recvmsg(fd, &msg, 0);
529 if (n < 0)
530 return -errno;
531
532 cmsg = CMSG_FIRSTHDR(&msg);
533 if (!cmsg ||
534 cmsg->cmsg_level != SOL_SOCKET ||
535 cmsg->cmsg_type != SCM_RIGHTS)
536 return n;
537
538 memcpy(fds, CMSG_DATA(cmsg), cmsg->cmsg_len - CMSG_LEN(0));
539 return n;
540}
541
542int os_create_unix_socket(const char *file, int len, int close_on_exec)
543{
544 struct sockaddr_un addr;
545 int sock, err;
546
547 sock = socket(PF_UNIX, SOCK_DGRAM, 0);
548 if (sock < 0)
549 return -errno;
550
551 if (close_on_exec) {
552 err = os_set_exec_close(sock);
553 if (err < 0)
554 printk(UM_KERN_ERR "create_unix_socket : "
555 "close_on_exec failed, err = %d", -err);
556 }
557
558 addr.sun_family = AF_UNIX;
559
560 snprintf(addr.sun_path, len, "%s", file);
561
562 err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
563 if (err < 0)
564 return -errno;
565
566 return sock;
567}
568
569void os_flush_stdout(void)
570{
571 fflush(stdout);
572}
573
574int os_lock_file(int fd, int excl)
575{
576 int type = excl ? F_WRLCK : F_RDLCK;
577 struct flock lock = ((struct flock) { .l_type = type,
578 .l_whence = SEEK_SET,
579 .l_start = 0,
580 .l_len = 0 } );
581 int err, save;
582
583 err = fcntl(fd, F_SETLK, &lock);
584 if (!err)
585 goto out;
586
587 save = -errno;
588 err = fcntl(fd, F_GETLK, &lock);
589 if (err) {
590 err = -errno;
591 goto out;
592 }
593
594 printk(UM_KERN_ERR "F_SETLK failed, file already locked by pid %d\n",
595 lock.l_pid);
596 err = save;
597 out:
598 return err;
599}
600
601unsigned os_major(unsigned long long dev)
602{
603 return major(dev);
604}
605
606unsigned os_minor(unsigned long long dev)
607{
608 return minor(dev);
609}
610
611unsigned long long os_makedev(unsigned major, unsigned minor)
612{
613 return makedev(major, minor);
614}
615
616int os_falloc_punch(int fd, unsigned long long offset, int len)
617{
618 int n = fallocate(fd, FALLOC_FL_PUNCH_HOLE|FALLOC_FL_KEEP_SIZE, offset, len);
619
620 if (n < 0)
621 return -errno;
622 return n;
623}
624
625int os_falloc_zeroes(int fd, unsigned long long offset, int len)
626{
627 int n = fallocate(fd, FALLOC_FL_ZERO_RANGE|FALLOC_FL_KEEP_SIZE, offset, len);
628
629 if (n < 0)
630 return -errno;
631 return n;
632}
633
634int os_eventfd(unsigned int initval, int flags)
635{
636 int fd = eventfd(initval, flags);
637
638 if (fd < 0)
639 return -errno;
640 return fd;
641}
642
643int os_sendmsg_fds(int fd, const void *buf, unsigned int len, const int *fds,
644 unsigned int fds_num)
645{
646 struct iovec iov = {
647 .iov_base = (void *) buf,
648 .iov_len = len,
649 };
650 union {
651 char control[CMSG_SPACE(sizeof(*fds) * OS_SENDMSG_MAX_FDS)];
652 struct cmsghdr align;
653 } u;
654 unsigned int fds_size = sizeof(*fds) * fds_num;
655 struct msghdr msg = {
656 .msg_iov = &iov,
657 .msg_iovlen = 1,
658 .msg_control = u.control,
659 .msg_controllen = CMSG_SPACE(fds_size),
660 };
661 struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
662 int err;
663
664 if (fds_num > OS_SENDMSG_MAX_FDS)
665 return -EINVAL;
666 memset(u.control, 0, sizeof(u.control));
667 cmsg->cmsg_level = SOL_SOCKET;
668 cmsg->cmsg_type = SCM_RIGHTS;
669 cmsg->cmsg_len = CMSG_LEN(fds_size);
670 memcpy(CMSG_DATA(cmsg), fds, fds_size);
671 err = sendmsg(fd, &msg, 0);
672
673 if (err < 0)
674 return -errno;
675 return err;
676}
677
678int os_poll(unsigned int n, const int *fds)
679{
680 /* currently need 2 FDs at most so avoid dynamic allocation */
681 struct pollfd pollfds[2] = {};
682 unsigned int i;
683 int ret;
684
685 if (n > ARRAY_SIZE(pollfds))
686 return -EINVAL;
687
688 for (i = 0; i < n; i++) {
689 pollfds[i].fd = fds[i];
690 pollfds[i].events = POLLIN;
691 }
692
693 ret = poll(pollfds, n, -1);
694 if (ret < 0)
695 return -errno;
696
697 /* Return the index of the available FD */
698 for (i = 0; i < n; i++) {
699 if (pollfds[i].revents)
700 return i;
701 }
702
703 return -EIO;
704}
705
706void *os_mmap_rw_shared(int fd, size_t size)
707{
708 void *res = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
709
710 if (res == MAP_FAILED)
711 return NULL;
712
713 return res;
714}
715
716void *os_mremap_rw_shared(void *old_addr, size_t old_size, size_t new_size)
717{
718 void *res;
719
720 res = mremap(old_addr, old_size, new_size, MREMAP_MAYMOVE, NULL);
721
722 if (res == MAP_FAILED)
723 return NULL;
724
725 return res;
726}