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