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
copy_stat(struct uml_stat * dst,const struct stat64 * src)26 static 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
os_stat_fd(const int fd,struct uml_stat * ubuf)44 int 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
os_stat_file(const char * file_name,struct uml_stat * ubuf)58 int 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
os_access(const char * file,int mode)72 int 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) */
os_ioctl_generic(int fd,unsigned int cmd,unsigned long arg)89 int 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 */
os_get_ifname(int fd,char * namebuf)101 int os_get_ifname(int fd, char* namebuf)
102 {
103 if (ioctl(fd, SIOCGIFNAME, namebuf) < 0)
104 return -errno;
105
106 return 0;
107 }
108
os_set_slip(int fd)109 int os_set_slip(int fd)
110 {
111 int disc, sencap;
112
113 disc = N_SLIP;
114 if (ioctl(fd, TIOCSETD, &disc) < 0)
115 return -errno;
116
117 sencap = 0;
118 if (ioctl(fd, SIOCSIFENCAP, &sencap) < 0)
119 return -errno;
120
121 return 0;
122 }
123
os_mode_fd(int fd,int mode)124 int os_mode_fd(int fd, int mode)
125 {
126 int err;
127
128 CATCH_EINTR(err = fchmod(fd, mode));
129 if (err < 0)
130 return -errno;
131
132 return 0;
133 }
134
os_file_type(char * file)135 int os_file_type(char *file)
136 {
137 struct uml_stat buf;
138 int err;
139
140 err = os_stat_file(file, &buf);
141 if (err < 0)
142 return err;
143
144 if (S_ISDIR(buf.ust_mode))
145 return OS_TYPE_DIR;
146 else if (S_ISLNK(buf.ust_mode))
147 return OS_TYPE_SYMLINK;
148 else if (S_ISCHR(buf.ust_mode))
149 return OS_TYPE_CHARDEV;
150 else if (S_ISBLK(buf.ust_mode))
151 return OS_TYPE_BLOCKDEV;
152 else if (S_ISFIFO(buf.ust_mode))
153 return OS_TYPE_FIFO;
154 else if (S_ISSOCK(buf.ust_mode))
155 return OS_TYPE_SOCK;
156 else return OS_TYPE_FILE;
157 }
158
os_file_mode(const char * file,struct openflags * mode_out)159 int os_file_mode(const char *file, struct openflags *mode_out)
160 {
161 int err;
162
163 *mode_out = OPENFLAGS();
164
165 err = access(file, W_OK);
166 if (err && (errno != EACCES))
167 return -errno;
168 else if (!err)
169 *mode_out = of_write(*mode_out);
170
171 err = access(file, R_OK);
172 if (err && (errno != EACCES))
173 return -errno;
174 else if (!err)
175 *mode_out = of_read(*mode_out);
176
177 return err;
178 }
179
os_open_file(const char * file,struct openflags flags,int mode)180 int os_open_file(const char *file, struct openflags flags, int mode)
181 {
182 int fd, err, f = 0;
183
184 if (flags.r && flags.w)
185 f = O_RDWR;
186 else if (flags.r)
187 f = O_RDONLY;
188 else if (flags.w)
189 f = O_WRONLY;
190 else f = 0;
191
192 if (flags.s)
193 f |= O_SYNC;
194 if (flags.c)
195 f |= O_CREAT;
196 if (flags.t)
197 f |= O_TRUNC;
198 if (flags.e)
199 f |= O_EXCL;
200 if (flags.a)
201 f |= O_APPEND;
202
203 fd = open64(file, f, mode);
204 if (fd < 0)
205 return -errno;
206
207 if (flags.cl && fcntl(fd, F_SETFD, 1)) {
208 err = -errno;
209 close(fd);
210 return err;
211 }
212
213 return fd;
214 }
215
os_connect_socket(const char * name)216 int os_connect_socket(const char *name)
217 {
218 struct sockaddr_un sock;
219 int fd, err;
220
221 sock.sun_family = AF_UNIX;
222 snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
223
224 fd = socket(AF_UNIX, SOCK_STREAM, 0);
225 if (fd < 0) {
226 err = -errno;
227 goto out;
228 }
229
230 err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
231 if (err) {
232 err = -errno;
233 goto out_close;
234 }
235
236 return fd;
237
238 out_close:
239 close(fd);
240 out:
241 return err;
242 }
243
os_dup_file(int fd)244 int os_dup_file(int fd)
245 {
246 int new_fd = dup(fd);
247
248 if (new_fd < 0)
249 return -errno;
250
251 return new_fd;
252 }
253
os_close_file(int fd)254 void os_close_file(int fd)
255 {
256 close(fd);
257 }
258
os_seek_file(int fd,unsigned long long offset)259 int os_seek_file(int fd, unsigned long long offset)
260 {
261 unsigned long long actual;
262
263 actual = lseek64(fd, offset, SEEK_SET);
264 if (actual != offset)
265 return -errno;
266 return 0;
267 }
268
os_read_file(int fd,void * buf,int len)269 int os_read_file(int fd, void *buf, int len)
270 {
271 int n = read(fd, buf, len);
272
273 if (n < 0)
274 return -errno;
275 return n;
276 }
277
os_pread_file(int fd,void * buf,int len,unsigned long long offset)278 int os_pread_file(int fd, void *buf, int len, unsigned long long offset)
279 {
280 int n = pread(fd, buf, len, offset);
281
282 if (n < 0)
283 return -errno;
284 return n;
285 }
286
os_write_file(int fd,const void * buf,int len)287 int os_write_file(int fd, const void *buf, int len)
288 {
289 int n = write(fd, (void *) buf, len);
290
291 if (n < 0)
292 return -errno;
293 return n;
294 }
295
os_sync_file(int fd)296 int os_sync_file(int fd)
297 {
298 int n = fdatasync(fd);
299
300 if (n < 0)
301 return -errno;
302 return n;
303 }
304
os_pwrite_file(int fd,const void * buf,int len,unsigned long long offset)305 int os_pwrite_file(int fd, const void *buf, int len, unsigned long long offset)
306 {
307 int n = pwrite(fd, (void *) buf, len, offset);
308
309 if (n < 0)
310 return -errno;
311 return n;
312 }
313
314
os_file_size(const char * file,unsigned long long * size_out)315 int os_file_size(const char *file, unsigned long long *size_out)
316 {
317 struct uml_stat buf;
318 int err;
319
320 err = os_stat_file(file, &buf);
321 if (err < 0) {
322 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
323 -err);
324 return err;
325 }
326
327 if (S_ISBLK(buf.ust_mode)) {
328 int fd;
329 long blocks;
330
331 fd = open(file, O_RDONLY, 0);
332 if (fd < 0) {
333 err = -errno;
334 printk(UM_KERN_ERR "Couldn't open \"%s\", "
335 "errno = %d\n", file, errno);
336 return err;
337 }
338 if (ioctl(fd, BLKGETSIZE, &blocks) < 0) {
339 err = -errno;
340 printk(UM_KERN_ERR "Couldn't get the block size of "
341 "\"%s\", errno = %d\n", file, errno);
342 close(fd);
343 return err;
344 }
345 *size_out = ((long long) blocks) * 512;
346 close(fd);
347 }
348 else *size_out = buf.ust_size;
349
350 return 0;
351 }
352
os_file_modtime(const char * file,long long * modtime)353 int os_file_modtime(const char *file, long long *modtime)
354 {
355 struct uml_stat buf;
356 int err;
357
358 err = os_stat_file(file, &buf);
359 if (err < 0) {
360 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
361 -err);
362 return err;
363 }
364
365 *modtime = buf.ust_mtime;
366 return 0;
367 }
368
os_set_exec_close(int fd)369 int os_set_exec_close(int fd)
370 {
371 int err;
372
373 CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC));
374
375 if (err < 0)
376 return -errno;
377 return err;
378 }
379
os_pipe(int * fds,int stream,int close_on_exec)380 int os_pipe(int *fds, int stream, int close_on_exec)
381 {
382 int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
383
384 err = socketpair(AF_UNIX, type, 0, fds);
385 if (err < 0)
386 return -errno;
387
388 if (!close_on_exec)
389 return 0;
390
391 err = os_set_exec_close(fds[0]);
392 if (err < 0)
393 goto error;
394
395 err = os_set_exec_close(fds[1]);
396 if (err < 0)
397 goto error;
398
399 return 0;
400
401 error:
402 printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n",
403 -err);
404 close(fds[1]);
405 close(fds[0]);
406 return err;
407 }
408
os_set_fd_async(int fd)409 int os_set_fd_async(int fd)
410 {
411 int err, flags;
412
413 flags = fcntl(fd, F_GETFL);
414 if (flags < 0)
415 return -errno;
416
417 flags |= O_ASYNC | O_NONBLOCK;
418 if (fcntl(fd, F_SETFL, flags) < 0) {
419 err = -errno;
420 printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC "
421 "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
422 return err;
423 }
424
425 if ((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
426 (fcntl(fd, F_SETOWN, os_getpid()) < 0)) {
427 err = -errno;
428 printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN "
429 "(or F_SETSIG) fd %d, errno = %d\n", fd, errno);
430 return err;
431 }
432
433 return 0;
434 }
435
os_clear_fd_async(int fd)436 int os_clear_fd_async(int fd)
437 {
438 int flags;
439
440 flags = fcntl(fd, F_GETFL);
441 if (flags < 0)
442 return -errno;
443
444 flags &= ~(O_ASYNC | O_NONBLOCK);
445 if (fcntl(fd, F_SETFL, flags) < 0)
446 return -errno;
447 return 0;
448 }
449
os_set_fd_block(int fd,int blocking)450 int os_set_fd_block(int fd, int blocking)
451 {
452 int flags;
453
454 flags = fcntl(fd, F_GETFL);
455 if (flags < 0)
456 return -errno;
457
458 if (blocking)
459 flags &= ~O_NONBLOCK;
460 else
461 flags |= O_NONBLOCK;
462
463 if (fcntl(fd, F_SETFL, flags) < 0)
464 return -errno;
465
466 return 0;
467 }
468
os_accept_connection(int fd)469 int os_accept_connection(int fd)
470 {
471 int new;
472
473 new = accept(fd, NULL, 0);
474 if (new < 0)
475 return -errno;
476 return new;
477 }
478
479 #ifndef SHUT_RD
480 #define SHUT_RD 0
481 #endif
482
483 #ifndef SHUT_WR
484 #define SHUT_WR 1
485 #endif
486
487 #ifndef SHUT_RDWR
488 #define SHUT_RDWR 2
489 #endif
490
os_shutdown_socket(int fd,int r,int w)491 int os_shutdown_socket(int fd, int r, int w)
492 {
493 int what, err;
494
495 if (r && w)
496 what = SHUT_RDWR;
497 else if (r)
498 what = SHUT_RD;
499 else if (w)
500 what = SHUT_WR;
501 else
502 return -EINVAL;
503
504 err = shutdown(fd, what);
505 if (err < 0)
506 return -errno;
507 return 0;
508 }
509
510 /**
511 * os_rcv_fd_msg - receive message with (optional) FDs
512 * @fd: the FD to receive from
513 * @fds: the array for FDs to write to
514 * @n_fds: number of FDs to receive (@fds array size)
515 * @data: the message buffer
516 * @data_len: the size of the message to receive
517 *
518 * Receive a message with FDs.
519 *
520 * Returns: the size of the received message, or an error code
521 */
os_rcv_fd_msg(int fd,int * fds,unsigned int n_fds,void * data,size_t data_len)522 ssize_t os_rcv_fd_msg(int fd, int *fds, unsigned int n_fds,
523 void *data, size_t data_len)
524 {
525 #define MAX_RCV_FDS 2
526 char buf[CMSG_SPACE(sizeof(*fds) * MAX_RCV_FDS)];
527 struct cmsghdr *cmsg;
528 struct iovec iov = {
529 .iov_base = data,
530 .iov_len = data_len,
531 };
532 struct msghdr msg = {
533 .msg_iov = &iov,
534 .msg_iovlen = 1,
535 .msg_control = buf,
536 .msg_controllen = CMSG_SPACE(sizeof(*fds) * n_fds),
537 };
538 int n;
539
540 if (n_fds > MAX_RCV_FDS)
541 return -EINVAL;
542
543 n = recvmsg(fd, &msg, 0);
544 if (n < 0)
545 return -errno;
546
547 cmsg = CMSG_FIRSTHDR(&msg);
548 if (!cmsg ||
549 cmsg->cmsg_level != SOL_SOCKET ||
550 cmsg->cmsg_type != SCM_RIGHTS)
551 return n;
552
553 memcpy(fds, CMSG_DATA(cmsg), cmsg->cmsg_len);
554 return n;
555 }
556
os_create_unix_socket(const char * file,int len,int close_on_exec)557 int os_create_unix_socket(const char *file, int len, int close_on_exec)
558 {
559 struct sockaddr_un addr;
560 int sock, err;
561
562 sock = socket(PF_UNIX, SOCK_DGRAM, 0);
563 if (sock < 0)
564 return -errno;
565
566 if (close_on_exec) {
567 err = os_set_exec_close(sock);
568 if (err < 0)
569 printk(UM_KERN_ERR "create_unix_socket : "
570 "close_on_exec failed, err = %d", -err);
571 }
572
573 addr.sun_family = AF_UNIX;
574
575 snprintf(addr.sun_path, len, "%s", file);
576
577 err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
578 if (err < 0)
579 return -errno;
580
581 return sock;
582 }
583
os_flush_stdout(void)584 void os_flush_stdout(void)
585 {
586 fflush(stdout);
587 }
588
os_lock_file(int fd,int excl)589 int os_lock_file(int fd, int excl)
590 {
591 int type = excl ? F_WRLCK : F_RDLCK;
592 struct flock lock = ((struct flock) { .l_type = type,
593 .l_whence = SEEK_SET,
594 .l_start = 0,
595 .l_len = 0 } );
596 int err, save;
597
598 err = fcntl(fd, F_SETLK, &lock);
599 if (!err)
600 goto out;
601
602 save = -errno;
603 err = fcntl(fd, F_GETLK, &lock);
604 if (err) {
605 err = -errno;
606 goto out;
607 }
608
609 printk(UM_KERN_ERR "F_SETLK failed, file already locked by pid %d\n",
610 lock.l_pid);
611 err = save;
612 out:
613 return err;
614 }
615
os_major(unsigned long long dev)616 unsigned os_major(unsigned long long dev)
617 {
618 return major(dev);
619 }
620
os_minor(unsigned long long dev)621 unsigned os_minor(unsigned long long dev)
622 {
623 return minor(dev);
624 }
625
os_makedev(unsigned major,unsigned minor)626 unsigned long long os_makedev(unsigned major, unsigned minor)
627 {
628 return makedev(major, minor);
629 }
630
os_falloc_punch(int fd,unsigned long long offset,int len)631 int os_falloc_punch(int fd, unsigned long long offset, int len)
632 {
633 int n = fallocate(fd, FALLOC_FL_PUNCH_HOLE|FALLOC_FL_KEEP_SIZE, offset, len);
634
635 if (n < 0)
636 return -errno;
637 return n;
638 }
639
os_falloc_zeroes(int fd,unsigned long long offset,int len)640 int os_falloc_zeroes(int fd, unsigned long long offset, int len)
641 {
642 int n = fallocate(fd, FALLOC_FL_ZERO_RANGE|FALLOC_FL_KEEP_SIZE, offset, len);
643
644 if (n < 0)
645 return -errno;
646 return n;
647 }
648
os_eventfd(unsigned int initval,int flags)649 int os_eventfd(unsigned int initval, int flags)
650 {
651 int fd = eventfd(initval, flags);
652
653 if (fd < 0)
654 return -errno;
655 return fd;
656 }
657
os_sendmsg_fds(int fd,const void * buf,unsigned int len,const int * fds,unsigned int fds_num)658 int os_sendmsg_fds(int fd, const void *buf, unsigned int len, const int *fds,
659 unsigned int fds_num)
660 {
661 struct iovec iov = {
662 .iov_base = (void *) buf,
663 .iov_len = len,
664 };
665 union {
666 char control[CMSG_SPACE(sizeof(*fds) * OS_SENDMSG_MAX_FDS)];
667 struct cmsghdr align;
668 } u;
669 unsigned int fds_size = sizeof(*fds) * fds_num;
670 struct msghdr msg = {
671 .msg_iov = &iov,
672 .msg_iovlen = 1,
673 .msg_control = u.control,
674 .msg_controllen = CMSG_SPACE(fds_size),
675 };
676 struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
677 int err;
678
679 if (fds_num > OS_SENDMSG_MAX_FDS)
680 return -EINVAL;
681 memset(u.control, 0, sizeof(u.control));
682 cmsg->cmsg_level = SOL_SOCKET;
683 cmsg->cmsg_type = SCM_RIGHTS;
684 cmsg->cmsg_len = CMSG_LEN(fds_size);
685 memcpy(CMSG_DATA(cmsg), fds, fds_size);
686 err = sendmsg(fd, &msg, 0);
687
688 if (err < 0)
689 return -errno;
690 return err;
691 }
692
os_poll(unsigned int n,const int * fds)693 int os_poll(unsigned int n, const int *fds)
694 {
695 /* currently need 2 FDs at most so avoid dynamic allocation */
696 struct pollfd pollfds[2] = {};
697 unsigned int i;
698 int ret;
699
700 if (n > ARRAY_SIZE(pollfds))
701 return -EINVAL;
702
703 for (i = 0; i < n; i++) {
704 pollfds[i].fd = fds[i];
705 pollfds[i].events = POLLIN;
706 }
707
708 ret = poll(pollfds, n, -1);
709 if (ret < 0)
710 return -errno;
711
712 /* Return the index of the available FD */
713 for (i = 0; i < n; i++) {
714 if (pollfds[i].revents)
715 return i;
716 }
717
718 return -EIO;
719 }
720
os_mmap_rw_shared(int fd,size_t size)721 void *os_mmap_rw_shared(int fd, size_t size)
722 {
723 void *res = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
724
725 if (res == MAP_FAILED)
726 return NULL;
727
728 return res;
729 }
730
os_mremap_rw_shared(void * old_addr,size_t old_size,size_t new_size)731 void *os_mremap_rw_shared(void *old_addr, size_t old_size, size_t new_size)
732 {
733 void *res;
734
735 res = mremap(old_addr, old_size, new_size, MREMAP_MAYMOVE, NULL);
736
737 if (res == MAP_FAILED)
738 return NULL;
739
740 return res;
741 }
742