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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
20static void copy_stat(struct uml_stat *dst, const struct stat64 *src)
21{
22 *dst = ((struct uml_stat) {
23 .ust_dev = src->st_dev,
24 .ust_ino = src->st_ino,
25 .ust_mode = src->st_mode,
26 .ust_nlink = src->st_nlink,
27 .ust_uid = src->st_uid,
28 .ust_gid = src->st_gid,
29 .ust_size = src->st_size,
30 .ust_blksize = src->st_blksize,
31 .ust_blocks = src->st_blocks,
32 .ust_atime = src->st_atime,
33 .ust_mtime = src->st_mtime,
34 .ust_ctime = src->st_ctime,
35 });
36}
37
38int 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
52int 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
66int 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
83int 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
95int os_get_ifname(int fd, char* namebuf)
96{
97 if (ioctl(fd, SIOCGIFNAME, namebuf) < 0)
98 return -errno;
99
100 return 0;
101}
102
103int 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
118int 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
129int 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
153int 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
174int 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
210int 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
232out_close:
233 close(fd);
234out:
235 return err;
236}
237
238void os_close_file(int fd)
239{
240 close(fd);
241}
242
243int 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
253int 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
262int 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
271int 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
309int 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
325int 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
336int 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
365int 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
392int 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
406int 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
425int 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
447int 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
466int 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
506int 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
533void os_flush_stdout(void)
534{
535 fflush(stdout);
536}
537
538int 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
