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