1/***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22#include "test.h"
23
24#ifdef HAVE_SYS_RESOURCE_H
25#include <sys/resource.h>
26#endif
27#ifdef HAVE_FCNTL_H
28#include <fcntl.h>
29#endif
30#include <limits.h>
31
32#include "warnless.h"
33#include "memdebug.h"
34
35#if !defined(HAVE_POLL_FINE) && \
36 !defined(USE_WINSOCK) && \
37 !defined(TPF) && \
38 !defined(FD_SETSIZE)
39#error "this test requires FD_SETSIZE"
40#endif
41
42#define SAFETY_MARGIN (11)
43
44#if defined(WIN32) || defined(_WIN32) || defined(MSDOS)
45#define DEV_NULL "NUL"
46#else
47#define DEV_NULL "/dev/null"
48#endif
49
50#if defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT)
51
52static int *fd = NULL;
53static struct rlimit num_open;
54static char msgbuff[256];
55
56static void store_errmsg(const char *msg, int err)
57{
58 if(!err)
59 msnprintf(msgbuff, sizeof(msgbuff), "%s", msg);
60 else
61 msnprintf(msgbuff, sizeof(msgbuff), "%s, errno %d, %s", msg, err,
62 strerror(err));
63}
64
65static void close_file_descriptors(void)
66{
67 for(num_open.rlim_cur = 0;
68 num_open.rlim_cur < num_open.rlim_max;
69 num_open.rlim_cur++)
70 if(fd[num_open.rlim_cur] > 0)
71 close(fd[num_open.rlim_cur]);
72 free(fd);
73 fd = NULL;
74}
75
76static int fopen_works(void)
77{
78 FILE *fpa[3];
79 int i;
80 int ret = 1;
81
82 for(i = 0; i < 3; i++) {
83 fpa[i] = NULL;
84 }
85 for(i = 0; i < 3; i++) {
86 fpa[i] = fopen(DEV_NULL, FOPEN_READTEXT);
87 if(fpa[i] == NULL) {
88 store_errmsg("fopen failed", errno);
89 fprintf(stderr, "%s\n", msgbuff);
90 ret = 0;
91 break;
92 }
93 }
94 for(i = 0; i < 3; i++) {
95 if(fpa[i] != NULL)
96 fclose(fpa[i]);
97 }
98 return ret;
99}
100
101static int rlimit(int keep_open)
102{
103 int *tmpfd;
104 rlim_t nitems, i;
105 int *memchunk = NULL;
106 char *fmt;
107 struct rlimit rl;
108 char strbuff[256];
109 char strbuff1[81];
110 char fmt_u[] = "%u";
111 char fmt_lu[] = "%lu";
112#ifdef HAVE_LONGLONG
113 char fmt_llu[] = "%llu";
114
115 if(sizeof(rl.rlim_max) > sizeof(long))
116 fmt = fmt_llu;
117 else
118#endif
119 fmt = (sizeof(rl.rlim_max) < sizeof(long))?fmt_u:fmt_lu;
120
121 /* get initial open file limits */
122
123 if(getrlimit(RLIMIT_NOFILE, &rl) != 0) {
124 store_errmsg("getrlimit() failed", errno);
125 fprintf(stderr, "%s\n", msgbuff);
126 return -1;
127 }
128
129 /* show initial open file limits */
130
131#ifdef RLIM_INFINITY
132 if(rl.rlim_cur == RLIM_INFINITY)
133 strcpy(strbuff, "INFINITY");
134 else
135#endif
136 msnprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_cur);
137 fprintf(stderr, "initial soft limit: %s\n", strbuff);
138
139#ifdef RLIM_INFINITY
140 if(rl.rlim_max == RLIM_INFINITY)
141 strcpy(strbuff, "INFINITY");
142 else
143#endif
144 msnprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_max);
145 fprintf(stderr, "initial hard limit: %s\n", strbuff);
146
147 /*
148 * if soft limit and hard limit are different we ask the
149 * system to raise soft limit all the way up to the hard
150 * limit. Due to some other system limit the soft limit
151 * might not be raised up to the hard limit. So from this
152 * point the resulting soft limit is our limit. Trying to
153 * open more than soft limit file descriptors will fail.
154 */
155
156 if(rl.rlim_cur != rl.rlim_max) {
157
158#ifdef OPEN_MAX
159 if((rl.rlim_cur > 0) &&
160 (rl.rlim_cur < OPEN_MAX)) {
161 fprintf(stderr, "raising soft limit up to OPEN_MAX\n");
162 rl.rlim_cur = OPEN_MAX;
163 if(setrlimit(RLIMIT_NOFILE, &rl) != 0) {
164 /* on failure don't abort just issue a warning */
165 store_errmsg("setrlimit() failed", errno);
166 fprintf(stderr, "%s\n", msgbuff);
167 msgbuff[0] = '\0';
168 }
169 }
170#endif
171
172 fprintf(stderr, "raising soft limit up to hard limit\n");
173 rl.rlim_cur = rl.rlim_max;
174 if(setrlimit(RLIMIT_NOFILE, &rl) != 0) {
175 /* on failure don't abort just issue a warning */
176 store_errmsg("setrlimit() failed", errno);
177 fprintf(stderr, "%s\n", msgbuff);
178 msgbuff[0] = '\0';
179 }
180
181 /* get current open file limits */
182
183 if(getrlimit(RLIMIT_NOFILE, &rl) != 0) {
184 store_errmsg("getrlimit() failed", errno);
185 fprintf(stderr, "%s\n", msgbuff);
186 return -3;
187 }
188
189 /* show current open file limits */
190
191#ifdef RLIM_INFINITY
192 if(rl.rlim_cur == RLIM_INFINITY)
193 strcpy(strbuff, "INFINITY");
194 else
195#endif
196 msnprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_cur);
197 fprintf(stderr, "current soft limit: %s\n", strbuff);
198
199#ifdef RLIM_INFINITY
200 if(rl.rlim_max == RLIM_INFINITY)
201 strcpy(strbuff, "INFINITY");
202 else
203#endif
204 msnprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_max);
205 fprintf(stderr, "current hard limit: %s\n", strbuff);
206
207 } /* (rl.rlim_cur != rl.rlim_max) */
208
209 /*
210 * test 537 is all about testing libcurl functionality
211 * when the system has nearly exhausted the number of
212 * available file descriptors. Test 537 will try to run
213 * with a very small number of file descriptors available.
214 * This implies that any file descriptor which is open
215 * when the test runs will have a number in the high range
216 * of whatever the system supports.
217 */
218
219 /*
220 * reserve a chunk of memory before opening file descriptors to
221 * avoid a low memory condition once the file descriptors are
222 * open. System conditions that could make the test fail should
223 * be addressed in the precheck phase. This chunk of memory shall
224 * be always free()ed before exiting the rlimit() function so
225 * that it becomes available to the test.
226 */
227
228 for(nitems = i = 1; nitems <= i; i *= 2)
229 nitems = i;
230 if(nitems > 0x7fff)
231 nitems = 0x40000;
232 do {
233 num_open.rlim_max = sizeof(*memchunk) * nitems;
234 msnprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
235 fprintf(stderr, "allocating memchunk %s byte array\n", strbuff);
236 memchunk = malloc(sizeof(*memchunk) * (size_t)nitems);
237 if(!memchunk) {
238 fprintf(stderr, "memchunk, malloc() failed\n");
239 nitems /= 2;
240 }
241 } while(nitems && !memchunk);
242 if(!memchunk) {
243 store_errmsg("memchunk, malloc() failed", errno);
244 fprintf(stderr, "%s\n", msgbuff);
245 return -4;
246 }
247
248 /* initialize it to fight lazy allocation */
249
250 fprintf(stderr, "initializing memchunk array\n");
251
252 for(i = 0; i < nitems; i++)
253 memchunk[i] = -1;
254
255 /* set the number of file descriptors we will try to open */
256
257#ifdef RLIM_INFINITY
258 if((rl.rlim_cur > 0) && (rl.rlim_cur != RLIM_INFINITY)) {
259#else
260 if(rl.rlim_cur > 0) {
261#endif
262 /* soft limit minus SAFETY_MARGIN */
263 num_open.rlim_max = rl.rlim_cur - SAFETY_MARGIN;
264 }
265 else {
266 /* a huge number of file descriptors */
267 for(nitems = i = 1; nitems <= i; i *= 2)
268 nitems = i;
269 if(nitems > 0x7fff)
270 nitems = 0x40000;
271 num_open.rlim_max = nitems;
272 }
273
274 /* verify that we won't overflow size_t in malloc() */
275
276 if((size_t)(num_open.rlim_max) > ((size_t)-1) / sizeof(*fd)) {
277 msnprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_max);
278 msnprintf(strbuff, sizeof(strbuff), "unable to allocate an array for %s "
279 "file descriptors, would overflow size_t", strbuff1);
280 store_errmsg(strbuff, 0);
281 fprintf(stderr, "%s\n", msgbuff);
282 free(memchunk);
283 return -5;
284 }
285
286 /* allocate array for file descriptors */
287
288 do {
289 msnprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
290 fprintf(stderr, "allocating array for %s file descriptors\n", strbuff);
291 fd = malloc(sizeof(*fd) * (size_t)(num_open.rlim_max));
292 if(!fd) {
293 fprintf(stderr, "fd, malloc() failed\n");
294 num_open.rlim_max /= 2;
295 }
296 } while(num_open.rlim_max && !fd);
297 if(!fd) {
298 store_errmsg("fd, malloc() failed", errno);
299 fprintf(stderr, "%s\n", msgbuff);
300 free(memchunk);
301 return -6;
302 }
303
304 /* initialize it to fight lazy allocation */
305
306 fprintf(stderr, "initializing fd array\n");
307
308 for(num_open.rlim_cur = 0;
309 num_open.rlim_cur < num_open.rlim_max;
310 num_open.rlim_cur++)
311 fd[num_open.rlim_cur] = -1;
312
313 msnprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
314 fprintf(stderr, "trying to open %s file descriptors\n", strbuff);
315
316 /* open a dummy descriptor */
317
318 fd[0] = open(DEV_NULL, O_RDONLY);
319 if(fd[0] < 0) {
320 msnprintf(strbuff, sizeof(strbuff), "opening of %s failed", DEV_NULL);
321 store_errmsg(strbuff, errno);
322 fprintf(stderr, "%s\n", msgbuff);
323 free(fd);
324 fd = NULL;
325 free(memchunk);
326 return -7;
327 }
328
329 /* create a bunch of file descriptors */
330
331 for(num_open.rlim_cur = 1;
332 num_open.rlim_cur < num_open.rlim_max;
333 num_open.rlim_cur++) {
334
335 fd[num_open.rlim_cur] = dup(fd[0]);
336
337 if(fd[num_open.rlim_cur] < 0) {
338
339 fd[num_open.rlim_cur] = -1;
340
341 msnprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_cur);
342 msnprintf(strbuff, sizeof(strbuff), "dup() attempt %s failed", strbuff1);
343 fprintf(stderr, "%s\n", strbuff);
344
345 msnprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_cur);
346 msnprintf(strbuff, sizeof(strbuff), "fds system limit seems close to %s",
347 strbuff1);
348 fprintf(stderr, "%s\n", strbuff);
349
350 num_open.rlim_max = num_open.rlim_cur - SAFETY_MARGIN;
351
352 num_open.rlim_cur -= num_open.rlim_max;
353 msnprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_cur);
354 msnprintf(strbuff, sizeof(strbuff), "closing %s file descriptors",
355 strbuff1);
356 fprintf(stderr, "%s\n", strbuff);
357
358 for(num_open.rlim_cur = num_open.rlim_max;
359 fd[num_open.rlim_cur] >= 0;
360 num_open.rlim_cur++) {
361 close(fd[num_open.rlim_cur]);
362 fd[num_open.rlim_cur] = -1;
363 }
364
365 msnprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
366 fprintf(stderr, "shrinking array for %s file descriptors\n", strbuff);
367
368 /* we don't care if we can't shrink it */
369
370 tmpfd = realloc(fd, sizeof(*fd) * (size_t)(num_open.rlim_max));
371 if(tmpfd) {
372 fd = tmpfd;
373 tmpfd = NULL;
374 }
375
376 break;
377
378 }
379
380 }
381
382 msnprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
383 fprintf(stderr, "%s file descriptors open\n", strbuff);
384
385#if !defined(HAVE_POLL_FINE) && \
386 !defined(USE_WINSOCK) && \
387 !defined(TPF)
388
389 /*
390 * when using select() instead of poll() we cannot test
391 * libcurl functionality with a socket number equal or
392 * greater than FD_SETSIZE. In any case, macro VERIFY_SOCK
393 * in lib/select.c enforces this check and protects libcurl
394 * from a possible crash. The effect of this protection
395 * is that test 537 will always fail, since the actual
396 * call to select() never takes place. We skip test 537
397 * with an indication that select limit would be exceeded.
398 */
399
400 num_open.rlim_cur = FD_SETSIZE - SAFETY_MARGIN;
401 if(num_open.rlim_max > num_open.rlim_cur) {
402 msnprintf(strbuff, sizeof(strbuff), "select limit is FD_SETSIZE %d",
403 FD_SETSIZE);
404 store_errmsg(strbuff, 0);
405 fprintf(stderr, "%s\n", msgbuff);
406 close_file_descriptors();
407 free(memchunk);
408 return -8;
409 }
410
411 num_open.rlim_cur = FD_SETSIZE - SAFETY_MARGIN;
412 for(rl.rlim_cur = 0;
413 rl.rlim_cur < num_open.rlim_max;
414 rl.rlim_cur++) {
415 if((fd[rl.rlim_cur] > 0) &&
416 ((unsigned int)fd[rl.rlim_cur] > num_open.rlim_cur)) {
417 msnprintf(strbuff, sizeof(strbuff), "select limit is FD_SETSIZE %d",
418 FD_SETSIZE);
419 store_errmsg(strbuff, 0);
420 fprintf(stderr, "%s\n", msgbuff);
421 close_file_descriptors();
422 free(memchunk);
423 return -9;
424 }
425 }
426
427#endif /* using a FD_SETSIZE bound select() */
428
429 /*
430 * Old or 'backwards compatible' implementations of stdio do not allow
431 * handling of streams with an underlying file descriptor number greater
432 * than 255, even when allowing high numbered file descriptors for sockets.
433 * At this point we have a big number of file descriptors which have been
434 * opened using dup(), so lets test the stdio implementation and discover
435 * if it is capable of fopen()ing some additional files.
436 */
437
438 if(!fopen_works()) {
439 msnprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_max);
440 msnprintf(strbuff, sizeof(strbuff), "fopen fails with %s fds open",
441 strbuff1);
442 fprintf(stderr, "%s\n", msgbuff);
443 msnprintf(strbuff, sizeof(strbuff), "fopen fails with lots of fds open");
444 store_errmsg(strbuff, 0);
445 close_file_descriptors();
446 free(memchunk);
447 return -10;
448 }
449
450 /* free the chunk of memory we were reserving so that it
451 becomes becomes available to the test */
452
453 free(memchunk);
454
455 /* close file descriptors unless instructed to keep them */
456
457 if(!keep_open) {
458 close_file_descriptors();
459 }
460
461 return 0;
462}
463
464int test(char *URL)
465{
466 CURLcode res;
467 CURL *curl;
468
469 if(!strcmp(URL, "check")) {
470 /* used by the test script to ask if we can run this test or not */
471 if(rlimit(FALSE)) {
472 fprintf(stdout, "rlimit problem: %s\n", msgbuff);
473 return 1;
474 }
475 return 0; /* sure, run this! */
476 }
477
478 if(rlimit(TRUE)) {
479 /* failure */
480 return TEST_ERR_MAJOR_BAD;
481 }
482
483 /* run the test with the bunch of open file descriptors
484 and close them all once the test is over */
485
486 if(curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
487 fprintf(stderr, "curl_global_init() failed\n");
488 close_file_descriptors();
489 return TEST_ERR_MAJOR_BAD;
490 }
491
492 curl = curl_easy_init();
493 if(!curl) {
494 fprintf(stderr, "curl_easy_init() failed\n");
495 close_file_descriptors();
496 curl_global_cleanup();
497 return TEST_ERR_MAJOR_BAD;
498 }
499
500 test_setopt(curl, CURLOPT_URL, URL);
501 test_setopt(curl, CURLOPT_HEADER, 1L);
502
503 res = curl_easy_perform(curl);
504
505test_cleanup:
506
507 close_file_descriptors();
508 curl_easy_cleanup(curl);
509 curl_global_cleanup();
510
511 return (int)res;
512}
513
514#else /* defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT) */
515
516int test(char *URL)
517{
518 (void)URL;
519 printf("system lacks necessary system function(s)");
520 return 1; /* skip test */
521}
522
523#endif /* defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT) */
524