1 /*
2  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3  * Licensed under the GPL
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/un.h>
16 #include "os.h"
17 
copy_stat(struct uml_stat * dst,const struct stat64 * src)18 static void copy_stat(struct uml_stat *dst, const struct stat64 *src)
19 {
20 	*dst = ((struct uml_stat) {
21 		.ust_dev     = src->st_dev,     /* device */
22 		.ust_ino     = src->st_ino,     /* inode */
23 		.ust_mode    = src->st_mode,    /* protection */
24 		.ust_nlink   = src->st_nlink,   /* number of hard links */
25 		.ust_uid     = src->st_uid,     /* user ID of owner */
26 		.ust_gid     = src->st_gid,     /* group ID of owner */
27 		.ust_size    = src->st_size,    /* total size, in bytes */
28 		.ust_blksize = src->st_blksize, /* blocksize for filesys I/O */
29 		.ust_blocks  = src->st_blocks,  /* number of blocks allocated */
30 		.ust_atime   = src->st_atime,   /* time of last access */
31 		.ust_mtime   = src->st_mtime,   /* time of last modification */
32 		.ust_ctime   = src->st_ctime,   /* time of last change */
33 	});
34 }
35 
os_stat_fd(const int fd,struct uml_stat * ubuf)36 int os_stat_fd(const int fd, struct uml_stat *ubuf)
37 {
38 	struct stat64 sbuf;
39 	int err;
40 
41 	CATCH_EINTR(err = fstat64(fd, &sbuf));
42 	if (err < 0)
43 		return -errno;
44 
45 	if (ubuf != NULL)
46 		copy_stat(ubuf, &sbuf);
47 	return err;
48 }
49 
os_stat_file(const char * file_name,struct uml_stat * ubuf)50 int os_stat_file(const char *file_name, struct uml_stat *ubuf)
51 {
52 	struct stat64 sbuf;
53 	int err;
54 
55 	CATCH_EINTR(err = stat64(file_name, &sbuf));
56 	if (err < 0)
57 		return -errno;
58 
59 	if (ubuf != NULL)
60 		copy_stat(ubuf, &sbuf);
61 	return err;
62 }
63 
os_access(const char * file,int mode)64 int os_access(const char *file, int mode)
65 {
66 	int amode, err;
67 
68 	amode = (mode & OS_ACC_R_OK ? R_OK : 0) |
69 		(mode & OS_ACC_W_OK ? W_OK : 0) |
70 		(mode & OS_ACC_X_OK ? X_OK : 0) |
71 		(mode & OS_ACC_F_OK ? F_OK : 0);
72 
73 	err = access(file, amode);
74 	if (err < 0)
75 		return -errno;
76 
77 	return 0;
78 }
79 
80 /* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
os_ioctl_generic(int fd,unsigned int cmd,unsigned long arg)81 int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
82 {
83 	int err;
84 
85 	err = ioctl(fd, cmd, arg);
86 	if (err < 0)
87 		return -errno;
88 
89 	return err;
90 }
91 
92 /* FIXME: ensure namebuf in os_get_if_name is big enough */
os_get_ifname(int fd,char * namebuf)93 int os_get_ifname(int fd, char* namebuf)
94 {
95 	if (ioctl(fd, SIOCGIFNAME, namebuf) < 0)
96 		return -errno;
97 
98 	return 0;
99 }
100 
os_set_slip(int fd)101 int os_set_slip(int fd)
102 {
103 	int disc, sencap;
104 
105 	disc = N_SLIP;
106 	if (ioctl(fd, TIOCSETD, &disc) < 0)
107 		return -errno;
108 
109 	sencap = 0;
110 	if (ioctl(fd, SIOCSIFENCAP, &sencap) < 0)
111 		return -errno;
112 
113 	return 0;
114 }
115 
os_mode_fd(int fd,int mode)116 int os_mode_fd(int fd, int mode)
117 {
118 	int err;
119 
120 	CATCH_EINTR(err = fchmod(fd, mode));
121 	if (err < 0)
122 		return -errno;
123 
124 	return 0;
125 }
126 
os_file_type(char * file)127 int os_file_type(char *file)
128 {
129 	struct uml_stat buf;
130 	int err;
131 
132 	err = os_stat_file(file, &buf);
133 	if (err < 0)
134 		return err;
135 
136 	if (S_ISDIR(buf.ust_mode))
137 		return OS_TYPE_DIR;
138 	else if (S_ISLNK(buf.ust_mode))
139 		return OS_TYPE_SYMLINK;
140 	else if (S_ISCHR(buf.ust_mode))
141 		return OS_TYPE_CHARDEV;
142 	else if (S_ISBLK(buf.ust_mode))
143 		return OS_TYPE_BLOCKDEV;
144 	else if (S_ISFIFO(buf.ust_mode))
145 		return OS_TYPE_FIFO;
146 	else if (S_ISSOCK(buf.ust_mode))
147 		return OS_TYPE_SOCK;
148 	else return OS_TYPE_FILE;
149 }
150 
os_file_mode(const char * file,struct openflags * mode_out)151 int os_file_mode(const char *file, struct openflags *mode_out)
152 {
153 	int err;
154 
155 	*mode_out = OPENFLAGS();
156 
157 	err = access(file, W_OK);
158 	if (err && (errno != EACCES))
159 		return -errno;
160 	else if (!err)
161 		*mode_out = of_write(*mode_out);
162 
163 	err = access(file, R_OK);
164 	if (err && (errno != EACCES))
165 		return -errno;
166 	else if (!err)
167 		*mode_out = of_read(*mode_out);
168 
169 	return err;
170 }
171 
os_open_file(const char * file,struct openflags flags,int mode)172 int os_open_file(const char *file, struct openflags flags, int mode)
173 {
174 	int fd, err, f = 0;
175 
176 	if (flags.r && flags.w)
177 		f = O_RDWR;
178 	else if (flags.r)
179 		f = O_RDONLY;
180 	else if (flags.w)
181 		f = O_WRONLY;
182 	else f = 0;
183 
184 	if (flags.s)
185 		f |= O_SYNC;
186 	if (flags.c)
187 		f |= O_CREAT;
188 	if (flags.t)
189 		f |= O_TRUNC;
190 	if (flags.e)
191 		f |= O_EXCL;
192 	if (flags.a)
193 		f |= O_APPEND;
194 
195 	fd = open64(file, f, mode);
196 	if (fd < 0)
197 		return -errno;
198 
199 	if (flags.cl && fcntl(fd, F_SETFD, 1)) {
200 		err = -errno;
201 		close(fd);
202 		return err;
203 	}
204 
205 	return fd;
206 }
207 
os_connect_socket(const char * name)208 int os_connect_socket(const char *name)
209 {
210 	struct sockaddr_un sock;
211 	int fd, err;
212 
213 	sock.sun_family = AF_UNIX;
214 	snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
215 
216 	fd = socket(AF_UNIX, SOCK_STREAM, 0);
217 	if (fd < 0) {
218 		err = -errno;
219 		goto out;
220 	}
221 
222 	err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
223 	if (err) {
224 		err = -errno;
225 		goto out_close;
226 	}
227 
228 	return fd;
229 
230 out_close:
231 	close(fd);
232 out:
233 	return err;
234 }
235 
os_close_file(int fd)236 void os_close_file(int fd)
237 {
238 	close(fd);
239 }
240 
os_seek_file(int fd,unsigned long long offset)241 int os_seek_file(int fd, unsigned long long offset)
242 {
243 	unsigned long long actual;
244 
245 	actual = lseek64(fd, offset, SEEK_SET);
246 	if (actual != offset)
247 		return -errno;
248 	return 0;
249 }
250 
os_read_file(int fd,void * buf,int len)251 int os_read_file(int fd, void *buf, int len)
252 {
253 	int n = read(fd, buf, len);
254 
255 	if (n < 0)
256 		return -errno;
257 	return n;
258 }
259 
os_write_file(int fd,const void * buf,int len)260 int os_write_file(int fd, const void *buf, int len)
261 {
262 	int n = write(fd, (void *) buf, len);
263 
264 	if (n < 0)
265 		return -errno;
266 	return n;
267 }
268 
os_file_size(const char * file,unsigned long long * size_out)269 int os_file_size(const char *file, unsigned long long *size_out)
270 {
271 	struct uml_stat buf;
272 	int err;
273 
274 	err = os_stat_file(file, &buf);
275 	if (err < 0) {
276 		printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
277 		       -err);
278 		return err;
279 	}
280 
281 	if (S_ISBLK(buf.ust_mode)) {
282 		int fd;
283 		long blocks;
284 
285 		fd = open(file, O_RDONLY, 0);
286 		if (fd < 0) {
287 			err = -errno;
288 			printk(UM_KERN_ERR "Couldn't open \"%s\", "
289 			       "errno = %d\n", file, errno);
290 			return err;
291 		}
292 		if (ioctl(fd, BLKGETSIZE, &blocks) < 0) {
293 			err = -errno;
294 			printk(UM_KERN_ERR "Couldn't get the block size of "
295 			       "\"%s\", errno = %d\n", file, errno);
296 			close(fd);
297 			return err;
298 		}
299 		*size_out = ((long long) blocks) * 512;
300 		close(fd);
301 	}
302 	else *size_out = buf.ust_size;
303 
304 	return 0;
305 }
306 
os_file_modtime(const char * file,unsigned long * modtime)307 int os_file_modtime(const char *file, unsigned long *modtime)
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 	*modtime = buf.ust_mtime;
320 	return 0;
321 }
322 
os_set_exec_close(int fd)323 int os_set_exec_close(int fd)
324 {
325 	int err;
326 
327 	CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC));
328 
329 	if (err < 0)
330 		return -errno;
331 	return err;
332 }
333 
os_pipe(int * fds,int stream,int close_on_exec)334 int os_pipe(int *fds, int stream, int close_on_exec)
335 {
336 	int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
337 
338 	err = socketpair(AF_UNIX, type, 0, fds);
339 	if (err < 0)
340 		return -errno;
341 
342 	if (!close_on_exec)
343 		return 0;
344 
345 	err = os_set_exec_close(fds[0]);
346 	if (err < 0)
347 		goto error;
348 
349 	err = os_set_exec_close(fds[1]);
350 	if (err < 0)
351 		goto error;
352 
353 	return 0;
354 
355  error:
356 	printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n",
357 	       -err);
358 	close(fds[1]);
359 	close(fds[0]);
360 	return err;
361 }
362 
os_set_fd_async(int fd)363 int os_set_fd_async(int fd)
364 {
365 	int err, flags;
366 
367 	flags = fcntl(fd, F_GETFL);
368 	if (flags < 0)
369 		return -errno;
370 
371 	flags |= O_ASYNC | O_NONBLOCK;
372 	if (fcntl(fd, F_SETFL, flags) < 0) {
373 		err = -errno;
374 		printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC "
375 		       "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
376 		return err;
377 	}
378 
379 	if ((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
380 	    (fcntl(fd, F_SETOWN, os_getpid()) < 0)) {
381 		err = -errno;
382 		printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN "
383 		       "(or F_SETSIG) fd %d, errno = %d\n", fd, errno);
384 		return err;
385 	}
386 
387 	return 0;
388 }
389 
os_clear_fd_async(int fd)390 int os_clear_fd_async(int fd)
391 {
392 	int flags;
393 
394 	flags = fcntl(fd, F_GETFL);
395 	if (flags < 0)
396 		return -errno;
397 
398 	flags &= ~(O_ASYNC | O_NONBLOCK);
399 	if (fcntl(fd, F_SETFL, flags) < 0)
400 		return -errno;
401 	return 0;
402 }
403 
os_set_fd_block(int fd,int blocking)404 int os_set_fd_block(int fd, int blocking)
405 {
406 	int flags;
407 
408 	flags = fcntl(fd, F_GETFL);
409 	if (flags < 0)
410 		return -errno;
411 
412 	if (blocking)
413 		flags &= ~O_NONBLOCK;
414 	else
415 		flags |= O_NONBLOCK;
416 
417 	if (fcntl(fd, F_SETFL, flags) < 0)
418 		return -errno;
419 
420 	return 0;
421 }
422 
os_accept_connection(int fd)423 int os_accept_connection(int fd)
424 {
425 	int new;
426 
427 	new = accept(fd, NULL, 0);
428 	if (new < 0)
429 		return -errno;
430 	return new;
431 }
432 
433 #ifndef SHUT_RD
434 #define SHUT_RD 0
435 #endif
436 
437 #ifndef SHUT_WR
438 #define SHUT_WR 1
439 #endif
440 
441 #ifndef SHUT_RDWR
442 #define SHUT_RDWR 2
443 #endif
444 
os_shutdown_socket(int fd,int r,int w)445 int os_shutdown_socket(int fd, int r, int w)
446 {
447 	int what, err;
448 
449 	if (r && w)
450 		what = SHUT_RDWR;
451 	else if (r)
452 		what = SHUT_RD;
453 	else if (w)
454 		what = SHUT_WR;
455 	else
456 		return -EINVAL;
457 
458 	err = shutdown(fd, what);
459 	if (err < 0)
460 		return -errno;
461 	return 0;
462 }
463 
os_rcv_fd(int fd,int * helper_pid_out)464 int os_rcv_fd(int fd, int *helper_pid_out)
465 {
466 	int new, n;
467 	char buf[CMSG_SPACE(sizeof(new))];
468 	struct msghdr msg;
469 	struct cmsghdr *cmsg;
470 	struct iovec iov;
471 
472 	msg.msg_name = NULL;
473 	msg.msg_namelen = 0;
474 	iov = ((struct iovec) { .iov_base  = helper_pid_out,
475 				.iov_len   = sizeof(*helper_pid_out) });
476 	msg.msg_iov = &iov;
477 	msg.msg_iovlen = 1;
478 	msg.msg_control = buf;
479 	msg.msg_controllen = sizeof(buf);
480 	msg.msg_flags = 0;
481 
482 	n = recvmsg(fd, &msg, 0);
483 	if (n < 0)
484 		return -errno;
485 	else if (n != iov.iov_len)
486 		*helper_pid_out = -1;
487 
488 	cmsg = CMSG_FIRSTHDR(&msg);
489 	if (cmsg == NULL) {
490 		printk(UM_KERN_ERR "rcv_fd didn't receive anything, "
491 		       "error = %d\n", errno);
492 		return -1;
493 	}
494 	if ((cmsg->cmsg_level != SOL_SOCKET) ||
495 	    (cmsg->cmsg_type != SCM_RIGHTS)) {
496 		printk(UM_KERN_ERR "rcv_fd didn't receive a descriptor\n");
497 		return -1;
498 	}
499 
500 	new = ((int *) CMSG_DATA(cmsg))[0];
501 	return new;
502 }
503 
os_create_unix_socket(const char * file,int len,int close_on_exec)504 int os_create_unix_socket(const char *file, int len, int close_on_exec)
505 {
506 	struct sockaddr_un addr;
507 	int sock, err;
508 
509 	sock = socket(PF_UNIX, SOCK_DGRAM, 0);
510 	if (sock < 0)
511 		return -errno;
512 
513 	if (close_on_exec) {
514 		err = os_set_exec_close(sock);
515 		if (err < 0)
516 			printk(UM_KERN_ERR "create_unix_socket : "
517 			       "close_on_exec failed, err = %d", -err);
518 	}
519 
520 	addr.sun_family = AF_UNIX;
521 
522 	snprintf(addr.sun_path, len, "%s", file);
523 
524 	err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
525 	if (err < 0)
526 		return -errno;
527 
528 	return sock;
529 }
530 
os_flush_stdout(void)531 void os_flush_stdout(void)
532 {
533 	fflush(stdout);
534 }
535 
os_lock_file(int fd,int excl)536 int os_lock_file(int fd, int excl)
537 {
538 	int type = excl ? F_WRLCK : F_RDLCK;
539 	struct flock lock = ((struct flock) { .l_type	= type,
540 					      .l_whence	= SEEK_SET,
541 					      .l_start	= 0,
542 					      .l_len	= 0 } );
543 	int err, save;
544 
545 	err = fcntl(fd, F_SETLK, &lock);
546 	if (!err)
547 		goto out;
548 
549 	save = -errno;
550 	err = fcntl(fd, F_GETLK, &lock);
551 	if (err) {
552 		err = -errno;
553 		goto out;
554 	}
555 
556 	printk(UM_KERN_ERR "F_SETLK failed, file already locked by pid %d\n",
557 	       lock.l_pid);
558 	err = save;
559  out:
560 	return err;
561 }
562 
os_major(unsigned long long dev)563 unsigned os_major(unsigned long long dev)
564 {
565 	return major(dev);
566 }
567 
os_minor(unsigned long long dev)568 unsigned os_minor(unsigned long long dev)
569 {
570 	return minor(dev);
571 }
572 
os_makedev(unsigned major,unsigned minor)573 unsigned long long os_makedev(unsigned major, unsigned minor)
574 {
575 	return makedev(major, minor);
576 }
577