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 <errno.h>
9 #include <fcntl.h>
10 #include <signal.h>
11 #include <linux/falloc.h>
12 #include <sys/ioctl.h>
13 #include <sys/mount.h>
14 #include <sys/socket.h>
15 #include <sys/stat.h>
16 #include <sys/sysmacros.h>
17 #include <sys/un.h>
18 #include <sys/types.h>
19 #include <sys/eventfd.h>
20 #include <os.h>
21
copy_stat(struct uml_stat * dst,const struct stat64 * src)22 static void copy_stat(struct uml_stat *dst, const struct stat64 *src)
23 {
24 *dst = ((struct uml_stat) {
25 .ust_dev = src->st_dev, /* device */
26 .ust_ino = src->st_ino, /* inode */
27 .ust_mode = src->st_mode, /* protection */
28 .ust_nlink = src->st_nlink, /* number of hard links */
29 .ust_uid = src->st_uid, /* user ID of owner */
30 .ust_gid = src->st_gid, /* group ID of owner */
31 .ust_size = src->st_size, /* total size, in bytes */
32 .ust_blksize = src->st_blksize, /* blocksize for filesys I/O */
33 .ust_blocks = src->st_blocks, /* number of blocks allocated */
34 .ust_atime = src->st_atime, /* time of last access */
35 .ust_mtime = src->st_mtime, /* time of last modification */
36 .ust_ctime = src->st_ctime, /* time of last change */
37 });
38 }
39
os_stat_fd(const int fd,struct uml_stat * ubuf)40 int os_stat_fd(const int fd, struct uml_stat *ubuf)
41 {
42 struct stat64 sbuf;
43 int err;
44
45 CATCH_EINTR(err = fstat64(fd, &sbuf));
46 if (err < 0)
47 return -errno;
48
49 if (ubuf != NULL)
50 copy_stat(ubuf, &sbuf);
51 return err;
52 }
53
os_stat_file(const char * file_name,struct uml_stat * ubuf)54 int os_stat_file(const char *file_name, struct uml_stat *ubuf)
55 {
56 struct stat64 sbuf;
57 int err;
58
59 CATCH_EINTR(err = stat64(file_name, &sbuf));
60 if (err < 0)
61 return -errno;
62
63 if (ubuf != NULL)
64 copy_stat(ubuf, &sbuf);
65 return err;
66 }
67
os_access(const char * file,int mode)68 int os_access(const char *file, int mode)
69 {
70 int amode, err;
71
72 amode = (mode & OS_ACC_R_OK ? R_OK : 0) |
73 (mode & OS_ACC_W_OK ? W_OK : 0) |
74 (mode & OS_ACC_X_OK ? X_OK : 0) |
75 (mode & OS_ACC_F_OK ? F_OK : 0);
76
77 err = access(file, amode);
78 if (err < 0)
79 return -errno;
80
81 return 0;
82 }
83
84 /* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
os_ioctl_generic(int fd,unsigned int cmd,unsigned long arg)85 int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
86 {
87 int err;
88
89 err = ioctl(fd, cmd, arg);
90 if (err < 0)
91 return -errno;
92
93 return err;
94 }
95
96 /* FIXME: ensure namebuf in os_get_if_name is big enough */
os_get_ifname(int fd,char * namebuf)97 int os_get_ifname(int fd, char* namebuf)
98 {
99 if (ioctl(fd, SIOCGIFNAME, namebuf) < 0)
100 return -errno;
101
102 return 0;
103 }
104
os_set_slip(int fd)105 int os_set_slip(int fd)
106 {
107 int disc, sencap;
108
109 disc = N_SLIP;
110 if (ioctl(fd, TIOCSETD, &disc) < 0)
111 return -errno;
112
113 sencap = 0;
114 if (ioctl(fd, SIOCSIFENCAP, &sencap) < 0)
115 return -errno;
116
117 return 0;
118 }
119
os_mode_fd(int fd,int mode)120 int os_mode_fd(int fd, int mode)
121 {
122 int err;
123
124 CATCH_EINTR(err = fchmod(fd, mode));
125 if (err < 0)
126 return -errno;
127
128 return 0;
129 }
130
os_file_type(char * file)131 int os_file_type(char *file)
132 {
133 struct uml_stat buf;
134 int err;
135
136 err = os_stat_file(file, &buf);
137 if (err < 0)
138 return err;
139
140 if (S_ISDIR(buf.ust_mode))
141 return OS_TYPE_DIR;
142 else if (S_ISLNK(buf.ust_mode))
143 return OS_TYPE_SYMLINK;
144 else if (S_ISCHR(buf.ust_mode))
145 return OS_TYPE_CHARDEV;
146 else if (S_ISBLK(buf.ust_mode))
147 return OS_TYPE_BLOCKDEV;
148 else if (S_ISFIFO(buf.ust_mode))
149 return OS_TYPE_FIFO;
150 else if (S_ISSOCK(buf.ust_mode))
151 return OS_TYPE_SOCK;
152 else return OS_TYPE_FILE;
153 }
154
os_file_mode(const char * file,struct openflags * mode_out)155 int os_file_mode(const char *file, struct openflags *mode_out)
156 {
157 int err;
158
159 *mode_out = OPENFLAGS();
160
161 err = access(file, W_OK);
162 if (err && (errno != EACCES))
163 return -errno;
164 else if (!err)
165 *mode_out = of_write(*mode_out);
166
167 err = access(file, R_OK);
168 if (err && (errno != EACCES))
169 return -errno;
170 else if (!err)
171 *mode_out = of_read(*mode_out);
172
173 return err;
174 }
175
os_open_file(const char * file,struct openflags flags,int mode)176 int os_open_file(const char *file, struct openflags flags, int mode)
177 {
178 int fd, err, f = 0;
179
180 if (flags.r && flags.w)
181 f = O_RDWR;
182 else if (flags.r)
183 f = O_RDONLY;
184 else if (flags.w)
185 f = O_WRONLY;
186 else f = 0;
187
188 if (flags.s)
189 f |= O_SYNC;
190 if (flags.c)
191 f |= O_CREAT;
192 if (flags.t)
193 f |= O_TRUNC;
194 if (flags.e)
195 f |= O_EXCL;
196 if (flags.a)
197 f |= O_APPEND;
198
199 fd = open64(file, f, mode);
200 if (fd < 0)
201 return -errno;
202
203 if (flags.cl && fcntl(fd, F_SETFD, 1)) {
204 err = -errno;
205 close(fd);
206 return err;
207 }
208
209 return fd;
210 }
211
os_connect_socket(const char * name)212 int os_connect_socket(const char *name)
213 {
214 struct sockaddr_un sock;
215 int fd, err;
216
217 sock.sun_family = AF_UNIX;
218 snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
219
220 fd = socket(AF_UNIX, SOCK_STREAM, 0);
221 if (fd < 0) {
222 err = -errno;
223 goto out;
224 }
225
226 err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
227 if (err) {
228 err = -errno;
229 goto out_close;
230 }
231
232 return fd;
233
234 out_close:
235 close(fd);
236 out:
237 return err;
238 }
239
os_close_file(int fd)240 void os_close_file(int fd)
241 {
242 close(fd);
243 }
os_fsync_file(int fd)244 int os_fsync_file(int fd)
245 {
246 if (fsync(fd) < 0)
247 return -errno;
248 return 0;
249 }
250
os_seek_file(int fd,unsigned long long offset)251 int os_seek_file(int fd, unsigned long long offset)
252 {
253 unsigned long long actual;
254
255 actual = lseek64(fd, offset, SEEK_SET);
256 if (actual != offset)
257 return -errno;
258 return 0;
259 }
260
os_read_file(int fd,void * buf,int len)261 int os_read_file(int fd, void *buf, int len)
262 {
263 int n = read(fd, buf, len);
264
265 if (n < 0)
266 return -errno;
267 return n;
268 }
269
os_pread_file(int fd,void * buf,int len,unsigned long long offset)270 int os_pread_file(int fd, void *buf, int len, unsigned long long offset)
271 {
272 int n = pread(fd, buf, len, offset);
273
274 if (n < 0)
275 return -errno;
276 return n;
277 }
278
os_write_file(int fd,const void * buf,int len)279 int os_write_file(int fd, const void *buf, int len)
280 {
281 int n = write(fd, (void *) buf, len);
282
283 if (n < 0)
284 return -errno;
285 return n;
286 }
287
os_sync_file(int fd)288 int os_sync_file(int fd)
289 {
290 int n = fsync(fd);
291
292 if (n < 0)
293 return -errno;
294 return n;
295 }
296
os_pwrite_file(int fd,const void * buf,int len,unsigned long long offset)297 int os_pwrite_file(int fd, const void *buf, int len, unsigned long long offset)
298 {
299 int n = pwrite(fd, (void *) buf, len, offset);
300
301 if (n < 0)
302 return -errno;
303 return n;
304 }
305
306
os_file_size(const char * file,unsigned long long * size_out)307 int os_file_size(const char *file, unsigned long long *size_out)
308 {
309 struct uml_stat buf;
310 int err;
311
312 err = os_stat_file(file, &buf);
313 if (err < 0) {
314 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
315 -err);
316 return err;
317 }
318
319 if (S_ISBLK(buf.ust_mode)) {
320 int fd;
321 long blocks;
322
323 fd = open(file, O_RDONLY, 0);
324 if (fd < 0) {
325 err = -errno;
326 printk(UM_KERN_ERR "Couldn't open \"%s\", "
327 "errno = %d\n", file, errno);
328 return err;
329 }
330 if (ioctl(fd, BLKGETSIZE, &blocks) < 0) {
331 err = -errno;
332 printk(UM_KERN_ERR "Couldn't get the block size of "
333 "\"%s\", errno = %d\n", file, errno);
334 close(fd);
335 return err;
336 }
337 *size_out = ((long long) blocks) * 512;
338 close(fd);
339 }
340 else *size_out = buf.ust_size;
341
342 return 0;
343 }
344
os_file_modtime(const char * file,unsigned long * modtime)345 int os_file_modtime(const char *file, unsigned long *modtime)
346 {
347 struct uml_stat buf;
348 int err;
349
350 err = os_stat_file(file, &buf);
351 if (err < 0) {
352 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
353 -err);
354 return err;
355 }
356
357 *modtime = buf.ust_mtime;
358 return 0;
359 }
360
os_set_exec_close(int fd)361 int os_set_exec_close(int fd)
362 {
363 int err;
364
365 CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC));
366
367 if (err < 0)
368 return -errno;
369 return err;
370 }
371
os_pipe(int * fds,int stream,int close_on_exec)372 int os_pipe(int *fds, int stream, int close_on_exec)
373 {
374 int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
375
376 err = socketpair(AF_UNIX, type, 0, fds);
377 if (err < 0)
378 return -errno;
379
380 if (!close_on_exec)
381 return 0;
382
383 err = os_set_exec_close(fds[0]);
384 if (err < 0)
385 goto error;
386
387 err = os_set_exec_close(fds[1]);
388 if (err < 0)
389 goto error;
390
391 return 0;
392
393 error:
394 printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n",
395 -err);
396 close(fds[1]);
397 close(fds[0]);
398 return err;
399 }
400
os_set_fd_async(int fd)401 int os_set_fd_async(int fd)
402 {
403 int err, flags;
404
405 flags = fcntl(fd, F_GETFL);
406 if (flags < 0)
407 return -errno;
408
409 flags |= O_ASYNC | O_NONBLOCK;
410 if (fcntl(fd, F_SETFL, flags) < 0) {
411 err = -errno;
412 printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC "
413 "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
414 return err;
415 }
416
417 if ((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
418 (fcntl(fd, F_SETOWN, os_getpid()) < 0)) {
419 err = -errno;
420 printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN "
421 "(or F_SETSIG) fd %d, errno = %d\n", fd, errno);
422 return err;
423 }
424
425 return 0;
426 }
427
os_clear_fd_async(int fd)428 int os_clear_fd_async(int fd)
429 {
430 int flags;
431
432 flags = fcntl(fd, F_GETFL);
433 if (flags < 0)
434 return -errno;
435
436 flags &= ~(O_ASYNC | O_NONBLOCK);
437 if (fcntl(fd, F_SETFL, flags) < 0)
438 return -errno;
439 return 0;
440 }
441
os_set_fd_block(int fd,int blocking)442 int os_set_fd_block(int fd, int blocking)
443 {
444 int flags;
445
446 flags = fcntl(fd, F_GETFL);
447 if (flags < 0)
448 return -errno;
449
450 if (blocking)
451 flags &= ~O_NONBLOCK;
452 else
453 flags |= O_NONBLOCK;
454
455 if (fcntl(fd, F_SETFL, flags) < 0)
456 return -errno;
457
458 return 0;
459 }
460
os_accept_connection(int fd)461 int os_accept_connection(int fd)
462 {
463 int new;
464
465 new = accept(fd, NULL, 0);
466 if (new < 0)
467 return -errno;
468 return new;
469 }
470
471 #ifndef SHUT_RD
472 #define SHUT_RD 0
473 #endif
474
475 #ifndef SHUT_WR
476 #define SHUT_WR 1
477 #endif
478
479 #ifndef SHUT_RDWR
480 #define SHUT_RDWR 2
481 #endif
482
os_shutdown_socket(int fd,int r,int w)483 int os_shutdown_socket(int fd, int r, int w)
484 {
485 int what, err;
486
487 if (r && w)
488 what = SHUT_RDWR;
489 else if (r)
490 what = SHUT_RD;
491 else if (w)
492 what = SHUT_WR;
493 else
494 return -EINVAL;
495
496 err = shutdown(fd, what);
497 if (err < 0)
498 return -errno;
499 return 0;
500 }
501
os_rcv_fd(int fd,int * helper_pid_out)502 int os_rcv_fd(int fd, int *helper_pid_out)
503 {
504 int new, n;
505 char buf[CMSG_SPACE(sizeof(new))];
506 struct msghdr msg;
507 struct cmsghdr *cmsg;
508 struct iovec iov;
509
510 msg.msg_name = NULL;
511 msg.msg_namelen = 0;
512 iov = ((struct iovec) { .iov_base = helper_pid_out,
513 .iov_len = sizeof(*helper_pid_out) });
514 msg.msg_iov = &iov;
515 msg.msg_iovlen = 1;
516 msg.msg_control = buf;
517 msg.msg_controllen = sizeof(buf);
518 msg.msg_flags = 0;
519
520 n = recvmsg(fd, &msg, 0);
521 if (n < 0)
522 return -errno;
523 else if (n != iov.iov_len)
524 *helper_pid_out = -1;
525
526 cmsg = CMSG_FIRSTHDR(&msg);
527 if (cmsg == NULL) {
528 printk(UM_KERN_ERR "rcv_fd didn't receive anything, "
529 "error = %d\n", errno);
530 return -1;
531 }
532 if ((cmsg->cmsg_level != SOL_SOCKET) ||
533 (cmsg->cmsg_type != SCM_RIGHTS)) {
534 printk(UM_KERN_ERR "rcv_fd didn't receive a descriptor\n");
535 return -1;
536 }
537
538 new = ((int *) CMSG_DATA(cmsg))[0];
539 return new;
540 }
541
os_create_unix_socket(const char * file,int len,int close_on_exec)542 int 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
os_flush_stdout(void)569 void os_flush_stdout(void)
570 {
571 fflush(stdout);
572 }
573
os_lock_file(int fd,int excl)574 int 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
os_major(unsigned long long dev)601 unsigned os_major(unsigned long long dev)
602 {
603 return major(dev);
604 }
605
os_minor(unsigned long long dev)606 unsigned os_minor(unsigned long long dev)
607 {
608 return minor(dev);
609 }
610
os_makedev(unsigned major,unsigned minor)611 unsigned long long os_makedev(unsigned major, unsigned minor)
612 {
613 return makedev(major, minor);
614 }
615
os_falloc_punch(int fd,unsigned long long offset,int len)616 int 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
os_eventfd(unsigned int initval,int flags)625 int os_eventfd(unsigned int initval, int flags)
626 {
627 int fd = eventfd(initval, flags);
628
629 if (fd < 0)
630 return -errno;
631 return fd;
632 }
633
os_sendmsg_fds(int fd,const void * buf,unsigned int len,const int * fds,unsigned int fds_num)634 int os_sendmsg_fds(int fd, const void *buf, unsigned int len, const int *fds,
635 unsigned int fds_num)
636 {
637 struct iovec iov = {
638 .iov_base = (void *) buf,
639 .iov_len = len,
640 };
641 union {
642 char control[CMSG_SPACE(sizeof(*fds) * OS_SENDMSG_MAX_FDS)];
643 struct cmsghdr align;
644 } u;
645 unsigned int fds_size = sizeof(*fds) * fds_num;
646 struct msghdr msg = {
647 .msg_iov = &iov,
648 .msg_iovlen = 1,
649 .msg_control = u.control,
650 .msg_controllen = CMSG_SPACE(fds_size),
651 };
652 struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
653 int err;
654
655 if (fds_num > OS_SENDMSG_MAX_FDS)
656 return -EINVAL;
657 memset(u.control, 0, sizeof(u.control));
658 cmsg->cmsg_level = SOL_SOCKET;
659 cmsg->cmsg_type = SCM_RIGHTS;
660 cmsg->cmsg_len = CMSG_LEN(fds_size);
661 memcpy(CMSG_DATA(cmsg), fds, fds_size);
662 err = sendmsg(fd, &msg, 0);
663
664 if (err < 0)
665 return -errno;
666 return err;
667 }
668