1 /*
2 * QEMU low level functions
3 *
4 * Copyright (c) 2003 Fabrice Bellard
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <stdarg.h>
27 #include <stdbool.h>
28 #include <string.h>
29 #include <errno.h>
30 #include <unistd.h>
31 #include <fcntl.h>
32
33 #ifndef _WIN32
34 #include <sys/socket.h>
35 #endif
36
37 /* Needed early for CONFIG_BSD etc. */
38 #include "config-host.h"
39
40 #if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE)
41 #include <sys/mman.h>
42 #endif
43
44 #ifdef CONFIG_SOLARIS
45 #include <sys/types.h>
46 #include <sys/statvfs.h>
47 /* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for
48 discussion about Solaris header problems */
49 extern int madvise(caddr_t, size_t, int);
50 #endif
51
52 #include "qemu-common.h"
53 #include "trace.h"
54 #include "qemu/sockets.h"
55 #include "monitor/monitor.h"
56
57 static bool fips_enabled = false;
58
59 static const char *qemu_version = QEMU_VERSION;
60
61 #ifndef CONFIG_ANDROID // See android/sockets.c instead.
socket_set_cork(int fd,int v)62 int socket_set_cork(int fd, int v)
63 {
64 #if defined(SOL_TCP) && defined(TCP_CORK)
65 return qemu_setsockopt(fd, SOL_TCP, TCP_CORK, &v, sizeof(v));
66 #else
67 return 0;
68 #endif
69 }
70
socket_set_nodelay(int fd)71 int socket_set_nodelay(int fd)
72 {
73 int v = 1;
74 return qemu_setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &v, sizeof(v));
75 }
76 #endif // !CONFIG_ANDROID
77
qemu_madvise(void * addr,size_t len,int advice)78 int qemu_madvise(void *addr, size_t len, int advice)
79 {
80 if (advice == QEMU_MADV_INVALID) {
81 errno = EINVAL;
82 return -1;
83 }
84 #if defined(CONFIG_MADVISE)
85 return madvise(addr, len, advice);
86 #elif defined(CONFIG_POSIX_MADVISE)
87 return posix_madvise(addr, len, advice);
88 #else
89 errno = EINVAL;
90 return -1;
91 #endif
92 }
93
94 #ifndef CONFIG_ANDROID
95 #ifndef _WIN32
96 /*
97 * Dups an fd and sets the flags
98 */
qemu_dup_flags(int fd,int flags)99 static int qemu_dup_flags(int fd, int flags)
100 {
101 int ret;
102 int serrno;
103 int dup_flags;
104
105 #ifdef F_DUPFD_CLOEXEC
106 ret = fcntl(fd, F_DUPFD_CLOEXEC, 0);
107 #else
108 ret = dup(fd);
109 if (ret != -1) {
110 qemu_set_cloexec(ret);
111 }
112 #endif
113 if (ret == -1) {
114 goto fail;
115 }
116
117 dup_flags = fcntl(ret, F_GETFL);
118 if (dup_flags == -1) {
119 goto fail;
120 }
121
122 if ((flags & O_SYNC) != (dup_flags & O_SYNC)) {
123 errno = EINVAL;
124 goto fail;
125 }
126
127 /* Set/unset flags that we can with fcntl */
128 if (fcntl(ret, F_SETFL, flags) == -1) {
129 goto fail;
130 }
131
132 /* Truncate the file in the cases that open() would truncate it */
133 if (flags & O_TRUNC ||
134 ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))) {
135 if (ftruncate(ret, 0) == -1) {
136 goto fail;
137 }
138 }
139
140 return ret;
141
142 fail:
143 serrno = errno;
144 if (ret != -1) {
145 close(ret);
146 }
147 errno = serrno;
148 return -1;
149 }
150
qemu_parse_fdset(const char * param)151 static int qemu_parse_fdset(const char *param)
152 {
153 return qemu_parse_fd(param);
154 }
155 #endif
156 #endif // !CONFIG_ANDROID
157
158 /*
159 * Opens a file with FD_CLOEXEC set
160 */
qemu_open(const char * name,int flags,...)161 int qemu_open(const char *name, int flags, ...)
162 {
163 int ret;
164 int mode = 0;
165
166 #ifndef CONFIG_ANDROID
167 #ifndef _WIN32
168 const char *fdset_id_str;
169
170 /* Attempt dup of fd from fd set */
171 if (strstart(name, "/dev/fdset/", &fdset_id_str)) {
172 int64_t fdset_id;
173 int fd, dupfd;
174
175 fdset_id = qemu_parse_fdset(fdset_id_str);
176 if (fdset_id == -1) {
177 errno = EINVAL;
178 return -1;
179 }
180
181 fd = monitor_fdset_get_fd(fdset_id, flags);
182 if (fd == -1) {
183 return -1;
184 }
185
186 dupfd = qemu_dup_flags(fd, flags);
187 if (dupfd == -1) {
188 return -1;
189 }
190
191 ret = monitor_fdset_dup_fd_add(fdset_id, dupfd);
192 if (ret == -1) {
193 close(dupfd);
194 errno = EINVAL;
195 return -1;
196 }
197 return dupfd;
198 }
199 #endif
200 #endif // !CONFIG_ANDROID
201
202 if (flags & O_CREAT) {
203 va_list ap;
204
205 va_start(ap, flags);
206 mode = va_arg(ap, int);
207 va_end(ap);
208 }
209
210 #ifdef O_CLOEXEC
211 ret = open(name, flags | O_CLOEXEC, mode);
212 #else
213 ret = open(name, flags, mode);
214 if (ret >= 0) {
215 qemu_set_cloexec(ret);
216 }
217 #endif
218
219 #ifdef O_DIRECT
220 if (ret == -1 && errno == EINVAL && (flags & O_DIRECT)) {
221 error_report("file system may not support O_DIRECT");
222 errno = EINVAL; /* in case it was clobbered */
223 }
224 #endif /* O_DIRECT */
225
226 return ret;
227 }
228
qemu_close(int fd)229 int qemu_close(int fd)
230 {
231 #ifndef CONFIG_ANDROID
232 int64_t fdset_id;
233
234 /* Close fd that was dup'd from an fdset */
235 fdset_id = monitor_fdset_dup_fd_find(fd);
236 if (fdset_id != -1) {
237 int ret;
238
239 ret = close(fd);
240 if (ret == 0) {
241 monitor_fdset_dup_fd_remove(fd);
242 }
243
244 return ret;
245 }
246 #endif
247 return close(fd);
248 }
249
250 /*
251 * A variant of write(2) which handles partial write.
252 *
253 * Return the number of bytes transferred.
254 * Set errno if fewer than `count' bytes are written.
255 *
256 * This function don't work with non-blocking fd's.
257 * Any of the possibilities with non-bloking fd's is bad:
258 * - return a short write (then name is wrong)
259 * - busy wait adding (errno == EAGAIN) to the loop
260 */
qemu_write_full(int fd,const void * buf,size_t count)261 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
262 {
263 ssize_t ret = 0;
264 ssize_t total = 0;
265
266 while (count) {
267 ret = write(fd, buf, count);
268 if (ret < 0) {
269 if (errno == EINTR)
270 continue;
271 break;
272 }
273
274 count -= ret;
275 buf += ret;
276 total += ret;
277 }
278
279 return total;
280 }
281
282 /*
283 * Opens a socket with FD_CLOEXEC set
284 */
qemu_socket(int domain,int type,int protocol)285 int qemu_socket(int domain, int type, int protocol)
286 {
287 int ret;
288
289 #ifdef SOCK_CLOEXEC
290 ret = socket(domain, type | SOCK_CLOEXEC, protocol);
291 if (ret != -1 || errno != EINVAL) {
292 return ret;
293 }
294 #endif
295 ret = socket(domain, type, protocol);
296 if (ret >= 0) {
297 qemu_set_cloexec(ret);
298 }
299
300 return ret;
301 }
302
303 #ifndef CONFIG_ANDROID
304 /*
305 * Accept a connection and set FD_CLOEXEC
306 */
qemu_accept(int s,struct sockaddr * addr,socklen_t * addrlen)307 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
308 {
309 int ret;
310
311 #ifdef CONFIG_ACCEPT4
312 ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
313 if (ret != -1 || errno != ENOSYS) {
314 return ret;
315 }
316 #endif
317 ret = accept(s, addr, addrlen);
318 if (ret >= 0) {
319 qemu_set_cloexec(ret);
320 }
321
322 return ret;
323 }
324 #endif
325
326 /*
327 * A variant of send(2) which handles partial write.
328 *
329 * Return the number of bytes transferred, which is only
330 * smaller than `count' if there is an error.
331 *
332 * This function won't work with non-blocking fd's.
333 * Any of the possibilities with non-bloking fd's is bad:
334 * - return a short write (then name is wrong)
335 * - busy wait adding (errno == EAGAIN) to the loop
336 */
qemu_send_full(int fd,const void * buf,size_t count,int flags)337 ssize_t qemu_send_full(int fd, const void *buf, size_t count, int flags)
338 {
339 ssize_t ret = 0;
340 ssize_t total = 0;
341
342 while (count) {
343 ret = send(fd, buf, count, flags);
344 if (ret < 0) {
345 if (errno == EINTR) {
346 continue;
347 }
348 break;
349 }
350
351 count -= ret;
352 buf += ret;
353 total += ret;
354 }
355
356 return total;
357 }
358
359 /*
360 * A variant of recv(2) which handles partial write.
361 *
362 * Return the number of bytes transferred, which is only
363 * smaller than `count' if there is an error.
364 *
365 * This function won't work with non-blocking fd's.
366 * Any of the possibilities with non-bloking fd's is bad:
367 * - return a short write (then name is wrong)
368 * - busy wait adding (errno == EAGAIN) to the loop
369 */
qemu_recv_full(int fd,void * buf,size_t count,int flags)370 ssize_t qemu_recv_full(int fd, void *buf, size_t count, int flags)
371 {
372 ssize_t ret = 0;
373 ssize_t total = 0;
374
375 while (count) {
376 ret = qemu_recv(fd, buf, count, flags);
377 if (ret <= 0) {
378 if (ret < 0 && errno == EINTR) {
379 continue;
380 }
381 break;
382 }
383
384 count -= ret;
385 buf += ret;
386 total += ret;
387 }
388
389 return total;
390 }
391
qemu_set_version(const char * version)392 void qemu_set_version(const char *version)
393 {
394 qemu_version = version;
395 }
396
qemu_get_version(void)397 const char *qemu_get_version(void)
398 {
399 return qemu_version;
400 }
401
fips_set_state(bool requested)402 void fips_set_state(bool requested)
403 {
404 #ifdef __linux__
405 if (requested) {
406 FILE *fds = fopen("/proc/sys/crypto/fips_enabled", "r");
407 if (fds != NULL) {
408 fips_enabled = (fgetc(fds) == '1');
409 fclose(fds);
410 }
411 }
412 #else
413 fips_enabled = false;
414 #endif /* __linux__ */
415
416 #ifdef _FIPS_DEBUG
417 fprintf(stderr, "FIPS mode %s (requested %s)\n",
418 (fips_enabled ? "enabled" : "disabled"),
419 (requested ? "enabled" : "disabled"));
420 #endif
421 }
422
fips_get_state(void)423 bool fips_get_state(void)
424 {
425 return fips_enabled;
426 }
427
428 #ifndef CONFIG_ANDROID
429 #ifdef _WIN32
socket_cleanup(void)430 static void socket_cleanup(void)
431 {
432 WSACleanup();
433 }
434 #endif
435
socket_init(void)436 int socket_init(void)
437 {
438 #ifdef _WIN32
439 WSADATA Data;
440 int ret, err;
441
442 ret = WSAStartup(MAKEWORD(2, 2), &Data);
443 if (ret != 0) {
444 err = WSAGetLastError();
445 fprintf(stderr, "WSAStartup: %d\n", err);
446 return -1;
447 }
448 atexit(socket_cleanup);
449 #endif
450 return 0;
451 }
452 #endif // !CONFIG_ANDROID
453
454 #ifndef CONFIG_IOVEC
455 /* helper function for iov_send_recv() */
456 static ssize_t
readv_writev(int fd,const struct iovec * iov,int iov_cnt,bool do_write)457 readv_writev(int fd, const struct iovec *iov, int iov_cnt, bool do_write)
458 {
459 unsigned i = 0;
460 ssize_t ret = 0;
461 while (i < iov_cnt) {
462 ssize_t r = do_write
463 ? write(fd, iov[i].iov_base, iov[i].iov_len)
464 : read(fd, iov[i].iov_base, iov[i].iov_len);
465 if (r > 0) {
466 ret += r;
467 } else if (!r) {
468 break;
469 } else if (errno == EINTR) {
470 continue;
471 } else {
472 /* else it is some "other" error,
473 * only return if there was no data processed. */
474 if (ret == 0) {
475 ret = -1;
476 }
477 break;
478 }
479 i++;
480 }
481 return ret;
482 }
483
484 ssize_t
readv(int fd,const struct iovec * iov,int iov_cnt)485 readv(int fd, const struct iovec *iov, int iov_cnt)
486 {
487 return readv_writev(fd, iov, iov_cnt, false);
488 }
489
490 ssize_t
writev(int fd,const struct iovec * iov,int iov_cnt)491 writev(int fd, const struct iovec *iov, int iov_cnt)
492 {
493 return readv_writev(fd, iov, iov_cnt, true);
494 }
495 #endif
496
497 #if defined(_WIN32) && !QEMU_GNUC_PREREQ(4,4)
498 // Older Mingw32 didn't provide these.
499 int asprintf( char **, const char *, ... );
500 int vasprintf( char **, const char *, va_list );
501
vasprintf(char ** sptr,const char * fmt,va_list argv)502 int vasprintf( char **sptr, const char *fmt, va_list argv )
503 {
504 int wanted = vsnprintf( *sptr = NULL, 0, fmt, argv );
505 if( (wanted > 0) && ((*sptr = malloc( 1 + wanted )) != NULL) )
506 return vsprintf( *sptr, fmt, argv );
507
508 return wanted;
509 }
510
asprintf(char ** sptr,const char * fmt,...)511 int asprintf( char **sptr, const char *fmt, ... )
512 {
513 int retval;
514 va_list argv;
515 va_start( argv, fmt );
516 retval = vasprintf( sptr, fmt, argv );
517 va_end( argv );
518 return retval;
519 }
520 #endif // _WIN32 && !QEMU_GNUC_PREREQ(4,4)
521